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Sample records for instream structures rock

  1. Australian experience of providing for fish passage at small instream structures

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, B. [Forest Hill, Victoria (Australia)

    2006-07-01

    Various instream structures have been constructed in Australia as a result of increasing agricultural activities. However, even small structures such as culverts and stream gauging stations can restrict essential fish movements and result in the extinction of local fish species. This paper discussed methods of modifying and designing new structures to ensure adequate fish passage. It was suggested that instream structures can provide for fish passage through the provision of bridges, or through the use of low profile structures for small weirs. Recommendations for site-specific instream structures included an assessment of fish species, topography, flow characteristics and cost effectiveness. Solutions for reducing the impact of small instream barriers to fish movement were also discussed. Provision for fish passage is an important consideration for planners and designers of dams. Legislation is now in place to ensure a planning and approval process prior to the commencement of construction and operation. It was concluded that significant works are now being undertaken to restore fish migration pathways caused by barriers that restrict fish movement. However, monitoring is needed to ensure that designs operate effectively. 17 refs., 3 figs.

  2. Australian experience of providing for fish passage at small instream structures

    International Nuclear Information System (INIS)

    Lewis, B.

    2006-01-01

    Various instream structures have been constructed in Australia as a result of increasing agricultural activities. However, even small structures such as culverts and stream gauging stations can restrict essential fish movements and result in the extinction of local fish species. This paper discussed methods of modifying and designing new structures to ensure adequate fish passage. It was suggested that instream structures can provide for fish passage through the provision of bridges, or through the use of low profile structures for small weirs. Recommendations for site-specific instream structures included an assessment of fish species, topography, flow characteristics and cost effectiveness. Solutions for reducing the impact of small instream barriers to fish movement were also discussed. Provision for fish passage is an important consideration for planners and designers of dams. Legislation is now in place to ensure a planning and approval process prior to the commencement of construction and operation. It was concluded that significant works are now being undertaken to restore fish migration pathways caused by barriers that restrict fish movement. However, monitoring is needed to ensure that designs operate effectively. 17 refs., 3 figs

  3. Australian experience of fish passage past instream structures

    International Nuclear Information System (INIS)

    Lewis, B.

    2008-01-01

    The growth in hydropower has resulted in the construction of various structures across rivers and streams, such as dams and weirs, which may impede essential fish movements and result in local extinctions of some fish species. When it is not practical to build instream structures that provide for fish passage, it may be appropriate to install some type of fishway. Site specific factors such as the fish species present, topography, flow characteristics and cost effectiveness will determine how best to provide for fish passage. The types of fishways suitable at small dams and weirs up to five metres high were described in this paper along with their benefits and effectiveness. The purpose was to provide simple and appropriate solutions that can improve the health of rivers considerably by managing the native aquatic habitat. The upstream passage past obstacles can be provided for through several types of fishways such as pool-type fishways, Denil fish passes, rock ramps, nature-like bypass channels, fish lifts or locks, collection and transportation facilities. In addition to environmental benefits, providing for fish passage can have long term social and economic benefits as well. 17 refs., 3 figs

  4. Physical modeling of river spanning rock structures: Evaluating interstitial flow, local hydraulics, downstream scour development, and structure stability

    Science.gov (United States)

    Collins, K.L.; Thornton, C.I.; Mefford, B.; Holmquist-Johnson, C. L.

    2009-01-01

    Rock weir and ramp structures uniquely serve a necessary role in river management: to meet water deliveries in an ecologically sound manner. Uses include functioning as low head diversion dams, permitting fish passage, creating habitat diversity, and stabilizing stream banks and profiles. Existing information on design and performance of in-stream rock structures does not provide the guidance necessary to implement repeatable and sustainable construction and retrofit techniques. As widespread use of rock structures increases, the need for reliable design methods with a broad range of applicability at individual sites grows as well. Rigorous laboratory testing programs were implemented at the U.S. Bureau of Reclamation (Reclamation) and at Colorado State University (CSU) as part of a multifaceted research project focused on expanding the current knowledge base and developing design methods to improve the success rate of river spanning rock structures in meeting project goals. Physical modeling at Reclamation is being used to measure, predict, and reduce interstitial flow through rock ramps. CSU is using physical testing to quantify and predict scour development downstream of rock weirs and its impact on the stability of rock structures. ?? 2009 ASCE.

  5. Instream Physical Habitat Modelling Types

    DEFF Research Database (Denmark)

    Conallin, John; Boegh, Eva; Krogsgaard, Jørgen

    2010-01-01

    The introduction of the EU Water Framework Directive (WFD) is providing member state water resource managers with significant challenges in relation to meeting the deadline for 'Good Ecological Status' by 2015. Overall, instream physical habitat modelling approaches have advantages and disadvanta......The introduction of the EU Water Framework Directive (WFD) is providing member state water resource managers with significant challenges in relation to meeting the deadline for 'Good Ecological Status' by 2015. Overall, instream physical habitat modelling approaches have advantages...... suit their situations. This paper analyses the potential of different methods available for water managers to assess hydrological and geomorphological impacts on the habitats of stream biota, as requested by the WFD. The review considers both conventional and new advanced research-based instream...... physical habitat models. In parametric and non-parametric regression models, model assumptions are often not satisfied and the models are difficult to transfer to other regions. Research-based methods such as the artificial neural networks and individual-based modelling have promising potential as water...

  6. Standardizing instream flow requirements at hydropower projects in the Cascade Mountains, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Smith, I.M.; Sale, M.J.

    1993-06-01

    Instream flow requirements are common mitigation measures instituted in the bypassed reaches of hydroelectric diversion projects. Currently, there are two extremes among the ways to determine instream flow requirements: generic standard-setting methods and detailed, habitat-based, impact assessment methods such as the Instream Flow Incremental Methodology (IFIM). Data from streams in Washington state show a consistent pattern in the instream flow requirements resulting from the IFIM. This pattern can be used to refine the simpler standard-setting approaches and thereby provide better estimates of flow needs during early stages of project design.

  7. In-stream contaminant interaction and transport

    International Nuclear Information System (INIS)

    Whelan, G.

    1983-07-01

    In order to assess contaminant exposure levels in biotic and abiotic pathways from waste-disposal sites, a comprehensive Multimedia Contaminant Environmental Exposure Assessment (MCEA) methodology using several mathematical models is being developed. Prior to a full development of the proposed methodology, a scaled-down version involving terrestrial plants, overland, and in-stream compartments was applied to an actual shallow land waste-disposal site. The purpose was to evaluate and demonstrate the attributes of the methodology. The in-stream component of the abbreviated methodology as it relates to Mortandad Canyon in Los Alamos, New Mexico is discussed herein. A two-year period was simulated consisting of six major runoff events which possessed a variety of distributions and magnitudes. The in-stream component of the methodology was composed of two models integrated to simulate the migration of radionuclides: DKWAV and TODAM. DKWAV is an unsteady, one-dimensional, second-order, explicit, finite difference, channel flow code which simulates the hydrodynamics in dendritric river systems and includes point and/or continuous lateral inflow and channel seepage. TODAM is an unsteady, one-dimensional, finite element, sediment-contaminant transport code which simulates the migration and fate of sediment and radionuclides in their dissolved and particulate phases by solving the general advection/diffusion equation with sink and source terms

  8. A water budget approach to instream flow maintenance

    International Nuclear Information System (INIS)

    Waddle, T.

    1991-01-01

    Storage reallocation is a current issue at many Federal water storage facilities that have hydroelectric generation. Allocation of storage to support instream flows is one of the changes being considered. In this paper, a portion of storage is dedicated to supplying instream flows. The author defines this storage account as a water budget and operate it to provide instream habitat below the reservoir. The author uses a limiting event model, the effective habitat time series, to determine when water budget releases will produce habitat benefits. The effective habitat time series acts as a surrogate for fish population and reflects the mid to long term influence of water management decisions on the life cycle of a fish species. The author develops an operation rule for the water budget that considers water rights and habitat events. The paper concludes by contrasting the habitat benefits of water budget operation with fixed minimum flow requirements

  9. Instream large wood: Denitrification hotspots with low N2O production

    Science.gov (United States)

    We examined the effect of instream large wood on denitrification capacity in two contrasting, lower order streams — one that drains an agricultural watershed with no riparian forest and minimal stores of instream large wood and another that drains a forested watershed with an ext...

  10. Structure analysis - chiromancy of the rock

    International Nuclear Information System (INIS)

    Huber, A.; Huber, M.

    1989-01-01

    The reader may initially be surprised by a comparison between structure analysis and palmistry which is, in effect, a comparison between a scientific research method on the one hand and art which is equated with magical powers on the other. In the figurative sense, however, these two fields have some points in common which should help us to obtain a first impression of the nature of geological structure analysis. Chiromancy uses the lines and the form of the hand to predict the character and the future of the person in question. In the same way, geologists use rocks and rock forms to obtain information on structure and behaviour of different formations. Structure analysis is a specialised field of geological investigation in which traces of deformation are interpreted as expressions of rockforming forces. This article discusses how and why the character of a rock formation as well as its past, present and even future behaviour can be determined using structure analysis. (author) 11 figs

  11. A Method for Optimal Allocation between Instream and Offstream Uses in the Maipo River in Central Chile

    Science.gov (United States)

    Génova, P. P.; Olivares, M. A.

    2016-12-01

    Minimum instream flows (MIF) have been established in Chile with the aim of protecting aquatic ecosystems. In practice, since current water law only allocates water rights to offstream water uses, MIF becomes the only instrument for instream water allocation. However, MIF do not necessarily maintain an adequate flow for instream uses. Moreover, an efficient allocation of water for instream uses requires the quantification of the benefits obtained from those uses, so that tradeoffs between instream and offstream water uses are properly considered. A model of optimal allocation between instream and offstream uses is elaborated. The proposed method combines two pieces of information. On one hand, benefits of instream use are represented by qualitative recreational benefit curves as a function of instream flow. On the other hand, the opportunity cost given by lost benefits of offstream uses is employed to develop a supply curve for instream flows. We applied this method to the case of the Maipo River, where the main water uses are recreation, hydropower production and drinking water. Based on available information we obtained the qualitative benefits of various recreational activities as a function of flow attributes. Then we developed flow attributes curves as a function of instream flow for a representative number of sections in the river. As a result we obtained the qualitative recreational benefit curve for each section. The marginal cost curve for instream flows was developed from the benefit functions of hydropower production interfering with recreation in the Maipo River. The purpose of this supply curve is to find a range of instream flow that will provide a better quality condition for recreation experience at a lower opportunity cost. Results indicate that offstream uses adversely influence recreational activities in the Maipo River in certain months of the year, significantly decreasing the quality of these in instream uses. As expected, the impact depends

  12. Musical Structure as Narrative in Rock

    Directory of Open Access Journals (Sweden)

    John Fernando Encarnacao

    2011-09-01

    Full Text Available In an attempt to take a fresh look at the analysis of form in rock music, this paper uses Susan McClary’s (2000 idea of ‘quest narrative’ in Western art music as a starting point. While much pop and rock adheres to the basic structure of the establishment of a home territory, episodes or adventures away, and then a return, my study suggests three categories of rock music form that provide alternatives to common combinations of verses, choruses and bridges through which the quest narrative is delivered. Labyrinth forms present more than the usual number of sections to confound our sense of ‘home’, and consequently of ‘quest’. Single-cell forms use repetition to suggest either a kind of stasis or to disrupt our expectations of beginning, middle and end. Immersive forms blur sectional divisions and invite more sensual and participatory responses to the recorded text. With regard to all of these alternative approaches to structure, Judy Lochhead’s (1992 concept of ‘forming’ is called upon to underline rock music forms that unfold as process, rather than map received formal constructs. Central to the argument are a couple of crucial definitions. Following Theodore Gracyk (1996, it is not songs, as such, but particular recordings that constitute rock music texts. Additionally, narrative is understood not in (direct relation to the lyrics of a song, nor in terms of artists’ biographies or the trajectories of musical styles, but considered in terms of musical structure. It is hoped that this outline of non-narrative musical structures in rock may have applications not only to other types of music, but to other time-based art forms.

  13. Review of mitigation methods for fish passage, instream flows, and water quality

    International Nuclear Information System (INIS)

    Railsback, S.F.

    1991-01-01

    This paper reports on current environmental mitigation practices at nonfederal hydropower projects. Information was obtained from project operators on dissolved oxygen (DO) mitigation, instream flows, upstream fish passage facilities, and downstream fish passage facilities. The most common method for DO mitigation is the use of spill flows, which are costly because of lost power generation. DO concentrations are commonly monitored, but biological effects of DO mitigation are not. At many projects, instream flow requirements have been set without reference to formalized methods. About half of the projects with instream flow requirements monitor flow rates, but few monitor fish populations to verify that instream flows are effective. Angled bar racks are the most commonly used downstream fish passage devices and fish ladders are the most commonly used upstream fish passage devices. Fish passage rates or populations have been monitored to verify the effectiveness of passage mitigation at few projects. This analysis is the first phase of an evaluation of the costs, benefits, and effectiveness of mitigation measures

  14. Direct and indirect drivers of instream wood in the interior Pacific Northwest, USA: decoupling climate, vegetation, disturbance, and geomorphic setting

    Directory of Open Access Journals (Sweden)

    Hough-Snee Nate

    2014-06-01

    Full Text Available Instream wood is a driver of geomorphic change in low-order streams, frequently altering morphodynamic processes. Instream wood is a frequently measured component of streams, yet it is a complex metric, responding to ecological and geomorphic forcings at a variety of scales. Here we seek to disentangle the relative importance of physical and biological processes that drive wood growth and delivery to streams across broad spatial extents. In so doing, we ask two primary questions: (1 is riparian vegetation a composite variable that captures the indirect effects of climate and disturbance on instream wood dynamics? (2 What are the direct and indirect relationships between geomorphic setting, vegetation, climate, disturbance, and instream wood dynamics? We measured riparian vegetation composition and wood frequency and volume at 720 headwater reaches within the American interior Pacific Northwest. We used ordination to identify relationships between vegetation and environmental attributes, and subsequently built a structural equation model to identify how climate and disturbance directly affect vegetation composition and how vegetation and geomorphic setting directly affect instream wood volume and frequency. We found that large wood volume and frequency are directly driven by vegetation composition and positively correlated to wildfire, elevation, stream gradient, and channel bankfull width. Indicator species at reaches with high volumes of wood were generally long-lived, conifer trees that persist for extended durations once delivered to stream habitats. Wood dynamics were also indirectly mediated by factors that shape vegetation: wildfire, precipitation, elevation, and temperature. We conclude that wood volume and frequency are driven by multiple interrelated climatic, geomorphic, and ecological variables. Vegetation composition and geomorphic setting directly mediate indirect relationships between landscape environmental processes and instream

  15. Instream wood loads in montane forest streams of the Colorado Front Range, USA

    Science.gov (United States)

    Jackson, Karen J.; Wohl, Ellen

    2015-04-01

    Although several studies examine instream wood loads and associated geomorphic effects in streams of subalpine forests in the U.S. Southern Rocky Mountains, little is known of instream wood loads in lower elevation, montane forests of the region. We compare instream wood loads and geomorphic effects between streams draining montane forest stands of differing age (old growth versus younger) and disturbance history (healthy versus infested by mountain pine beetles). We examined forest stand characteristics, instream wood load, channel geometry, pool volume, and sediment storage in 33 pool-riffle or plane-bed stream reaches with objectives of determining whether (i) instream wood and geomorphic effects differed significantly among old-growth, younger, healthy, and beetle-infested forest stands and (ii) wood loads correlated with valley and channel characteristics. Wood loads were standardized to drainage area, stream gradient, reach length, bankfull width, and floodplain area. Streams flowing through old-growth forests had significantly larger wood loads and logjam volumes (pairwise t-tests), as well as logjam frequencies (Kruskal-Wallis test), residual pool volume, and fine sediment storage around wood than streams flowing through younger forests. Wood loads in streams draining beetle-infested forest did not differ significantly from those in healthy forest stands, but best subset regression models indicated that elevation, stand age, and beetle infestation were the best predictors of wood loads in channels and on floodplains, suggesting that beetle infestation is affecting instream wood characteristics. Wood loads are larger than values from subalpine streams in the same region and jams are larger and more closely spaced. We interpret these differences to reflect greater wood piece mobility in subalpine zone streams. Stand age appears to exert the dominant influence on instream wood characteristics within pool-riffle streams in the study area rather than beetle

  16. InSTREAM: the individual-based stream trout research and environmental assessment model

    Science.gov (United States)

    Steven F. Railsback; Bret C. Harvey; Stephen K. Jackson; Roland H. Lamberson

    2009-01-01

    This report documents Version 4.2 of InSTREAM, including its formulation, software, and application to research and management problems. InSTREAM is a simulation model designed to understand how stream and river salmonid populations respond to habitat alteration, including altered flow, temperature, and turbidity regimes and changes in channel morphology. The model...

  17. Aquatic habitat measurement and valuation: imputing social benefits to instream flow levels

    Science.gov (United States)

    Douglas, Aaron J.; Johnson, Richard L.

    1991-01-01

    Instream flow conflicts have been analysed from the perspectives offered by policy oriented applied (physical) science, theories of conflict resolution and negotiation strategy, and psychological analyses of the behavior patterns of the bargaining parties. Economics also offers some useful insights in analysing conflict resolution within the context of these water allocation problems. We attempt to analyse the economics of the bargaining process in conjunction with a discussion of the water allocation process. In particular, we examine in detail the relation between certain habitat estimation techniques, and the socially optimal allocation of non-market resources. The results developed here describe the welfare implications implicit in the contemporary general equilibrium analysis of a competitive market economy. We also review certain currently available techniques for assigning dollar values to the social benefits of instream flow. The limitations of non-market valuation techniques with respect to estimating the benefits provided by instream flows and the aquatic habitat contingent on these flows should not deter resource managers from using economic analysis as a basic tool for settling instream flow conflicts.

  18. Occurrence and in-stream attenuation of wastewater-derived pharmaceuticals in Iberian rivers.

    Science.gov (United States)

    Acuña, Vicenç; von Schiller, Daniel; García-Galán, Maria Jesús; Rodríguez-Mozaz, Sara; Corominas, Lluís; Petrovic, Mira; Poch, Manel; Barceló, Damià; Sabater, Sergi

    2015-01-15

    A multitude of pharmaceuticals enter surface waters via discharges of wastewater treatment plants (WWTPs), and many raise environmental and health concerns. Chemical fate models predict their concentrations using estimates of mass loading, dilution and in-stream attenuation. However, current comprehension of the attenuation rates remains a limiting factor for predictive models. We assessed in-stream attenuation of 75 pharmaceuticals in 4 river segments, aiming to characterize in-stream attenuation variability among different pharmaceutical compounds, as well as among river segments differing in environmental conditions. Our study revealed that in-stream attenuation was highly variable among pharmaceuticals and river segments and that none of the considered pharmaceutical physicochemical and molecular properties proved to be relevant in determining the mean attenuation rates. Instead, the octanol-water partition coefficient (Kow) influenced the variability of rates among river segments, likely due to its effect on sorption to sediments and suspended particles, and therefore influencing the balance between the different attenuation mechanisms (biotransformation, photolysis, sorption, and volatilization). The magnitude of the measured attenuation rates urges scientists to consider them as important as dilution when aiming to predict concentrations in freshwater ecosystems. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Role of Lithology and Rock Structure in Drainage Development in ...

    African Journals Online (AJOL)

    Lithology and Rock structure play a vital role in the development of Drainage Network in any drainage basin. The drainage patterns upon land surface develop as directed by the underlying lithology and rock structure. In fact, lithology and rock structure together shape the basin and are decisive parameters of nature and ...

  20. A structural behavior study of rock caverns considering the effects of discontinuities

    International Nuclear Information System (INIS)

    Kim, Jhin Wung; Kim, Sun Hoon; Seo, Jeong Moon; Choi, Kyu Seop; Kim, Dae Hong; Lee, Kyung Jin; Choi, In Gil; Lee, Dong Yong

    1990-06-01

    The objective of this study is to understand the effects of discontinuities within rock masses on the structural behavior of underground rock caverns for radioactive waste disposal, and then develop a computer program for the structural analysis of rock caverns considering these effect of discontinuities. The behavior of rock masses, such as strength, deformation modes, ect., is very difficult to predict because discontinuities in the form of microcracks or joints are randomly distributed within rock masses. Discontinuties existing around the rock cavern for underground radioactive waste disposal may become the main transport pathways of radionuclides, and reduce the strength of rock masses eventually causing the rock cavern structure unstable. Therefore, a comprehensive understanding of the mechanical properties and behavior of discontinuous rock masses and an improvement of structural analysis methods are essential in order to understand the behavior of underground rock cavern structures properly in order to design safe and economic understanding the behavior of discontinuous rock masses is essential. Therfore, this study includes literature review on mechanical properties of and computational models for discontinuous rock masses, and on structures. Then, bases on the engineering judgement a suitable selection and slight modifications on computational models and analysis methods have been made before developing the structural analysis computer program for underground radioactive waste disposal structures. (author)

  1. A thermo-elastic model for soft rocks considering structure

    International Nuclear Information System (INIS)

    He, Z.; Zhang, S.; Teng, J.; Xiong, Y.

    2017-01-01

    In the fields of nuclear waste geological deposit, geothermal energy and deep mining, the effects of temperature on the mechanical behaviors of soft rocks cannot be neglected. Experimental data in the literature also showed that the structure of soft rocks cannot be ignored. Based on the super-loading yield surface and the concept of temperature-deduced equivalent stress, a thermo-elastoplastic model for soft rocks is proposed considering the structure. Compared to the super-loading yield surface, only one parameter is added, i.e. the linear thermal expansion coefficient. The predicted results and the comparisons with experimental data in the literature show that the proposed model is capable of simultaneously describing heat increase and heat decrease of soft rocks. A stronger initial structure leads to a greater strength of the soft rocks. Heat increase and heat decrease can be converted between each other due to the change of the initial structure of soft rocks. Furthermore, regardless of the heat increase or heat decrease, a larger linear thermal expansion coefficient or a greater temperature always leads to a much rapider degradation of the structure. The degradation trend will be more obvious for the coupled greater values of linear thermal expansion coefficient and temperature. Lastly, compared to heat decrease, the structure will degrade more easily in the case of heat increase. (authors)

  2. A thermo-elastoplastic model for soft rocks considering structure

    Science.gov (United States)

    He, Zuoyue; Zhang, Sheng; Teng, Jidong; Xiong, Yonglin

    2017-11-01

    In the fields of nuclear waste geological deposit, geothermy and deep mining, the effects of temperature on the mechanical behaviors of soft rocks cannot be neglected. Experimental data in the literature also showed that the structure of soft rocks cannot be ignored. Based on the superloading yield surface and the concept of temperature-deduced equivalent stress, a thermo-elastoplastic model for soft rocks is proposed considering the structure. Compared to the superloading yield surface, only one parameter is added, i.e. the linear thermal expansion coefficient. The predicted results and the comparisons with experimental data in the literature show that the proposed model is capable of simultaneously describing heat increase and heat decrease of soft rocks. A stronger initial structure leads to a greater strength of the soft rocks. Heat increase and heat decrease can be converted between each other due to the change of the initial structure of soft rocks. Furthermore, regardless of the heat increase or heat decrease, a larger linear thermal expansion coefficient or a greater temperature always leads to a much rapider degradation of the structure. The degradation trend will be more obvious for the coupled greater values of linear thermal expansion coefficient and temperature. Lastly, compared to heat decrease, the structure will degrade more easily in the case of heat increase.

  3. QUANTIFICATION OF INSTREAM FLOW NEEDS OF A WILD AND SCENIC RIVER FOR WATER RIGHTS LITIGATION.

    Science.gov (United States)

    Garn, Herbert S.

    1986-01-01

    The lower 4 miles of the Red River, a tributary of the Rio Grande in northern New Mexico, was designated as one of the 'instant' components of the National Wild and Scenic River System in 1968. Instream flow requirements were determined by several methods to quantify the claims made by the United States for a federal reserved water right under the Wild and Scenic Rivers Act. The scenic (aesthetic), recreational, and fish and wildlife values are the purposes for which instream flow requirements were claimed. Since water quality is related to these values, instream flows for waste transport and protection of water quality were also included in the claim. The U. S. Fish and Wildlife Service's Instream Flow Incremental Methodology was used to quantify the relationship between various flow regimes and fish habitat. Study results are discussed.

  4. Instream flow needs below peaking hydroelectric projects

    International Nuclear Information System (INIS)

    Milhous, R.T.

    1991-01-01

    This paper reports on a method developed to assist in the determination of instream flow needs below hydroelectric projects operated in a peaking mode. Peaking hydroelectric projects significantly change streamflow over a short period of time; consequently, any instream flow methodology must consider the dual flows associated with peaking projects. The dual flows are the lowest flow and the maximum generation flow of a peaking cycle. The methodology is based on elements of the Physical Habitat Simulation System of the U.S. Fish and Wildlife Service and uses habitat, rather than fish numbers or biomas, as at basic response variable. All aquatic animals are subject to the rapid changes in streamflow which cause rapid swings in habitat quality. Some aquatic organisms are relatively fixed in location in the stream while others can move when flows change. The habitat available from a project operated in peaking mode is considered to be the minimum habitat occurring during a cycle of habitat change. The methodology takes in to consideration that some aquatic animals can move and others cannot move during a peaking cycle

  5. A new method to test rock abrasiveness based on physico-mechanical and structural properties of rocks

    Directory of Open Access Journals (Sweden)

    V.N. Oparin

    2015-06-01

    Full Text Available A new method to test rock abrasiveness is proposed based upon the dependence of rock abrasiveness on their structural and physico-mechanical properties. The article describes the procedure of presentation of properties that govern rock abrasiveness on a canonical scale by dimensionless components, and the integrated estimation of the properties by a generalized index. The obtained results are compared with the known classifications of rock abrasiveness.

  6. Calculation of the Instream Ecological Flow of the Wei River Based on Hydrological Variation

    Directory of Open Access Journals (Sweden)

    Shengzhi Huang

    2014-01-01

    Full Text Available It is of great significance for the watershed management department to reasonably allocate water resources and ensure the sustainable development of river ecosystems. The greatly important issue is to accurately calculate instream ecological flow. In order to precisely compute instream ecological flow, flow variation is taken into account in this study. Moreover, the heuristic segmentation algorithm that is suitable to detect the mutation points of flow series is employed to identify the change points. Besides, based on the law of tolerance and ecological adaptation theory, the maximum instream ecological flow is calculated, which is the highest frequency of the monthly flow based on the GEV distribution and very suitable for healthy development of the river ecosystems. Furthermore, in order to guarantee the sustainable development of river ecosystems under some bad circumstances, minimum instream ecological flow is calculated by a modified Tennant method which is improved by replacing the average flow with the highest frequency of flow. Since the modified Tennant method is more suitable to reflect the law of flow, it has physical significance, and the calculation results are more reasonable.

  7. Rocking motion of structures under earthquakes. Overturning of 2-DOF system

    International Nuclear Information System (INIS)

    Kobayashi, Koichi; Watanabe, Tetsuya; Tanaka, Kihachiro; Tomoda, Akinori

    2011-01-01

    In recent years, huge earthquakes happen, for example, The South Hyogo prefecture Earthquake in 1995, The Mid Niigata Prefecture Earthquake in 2004, The Iwate-Miyagi Nairiku Earthquake in 2008. In The Niigataken Chuetsu-oki Earthquake in 2007, hundreds of drums fell down and water spilled out. A lot of studies about rocking behavior of rigid body had been performed from 1960's. However, these studies were only for a specific condition of the structure size or input vibration characteristics. Therefore, generalizes fall condition for earthquake is required. This paper deals with the analytical and the experimental study of the rocking vibration of 1-DOF rocking system, 2-DOF vibration-rocking system and 2-DOF rocking system under earthquakes. In this study, the equation of motion for each rocking systems are developed. The numerical model of 2-DOF rocking system is evaluated by free rocking experiment. In this paper, 'Overturning Map' which can distinguish whether structures falls or not is proposed. The overturning map of each rocking systems excited by the artificial earthquake wave calculated from the design spectrum is shown. As the result, overturning condition of structures is clarified. (author)

  8. Toward Design Guidelines for Stream Restoration Structures: Measuring and Modeling Unsteady Turbulent Flows in Natural Streams with Complex Hydraulic Structures

    Science.gov (United States)

    Lightbody, A.; Sotiropoulos, F.; Kang, S.; Diplas, P.

    2009-12-01

    Despite their widespread application to prevent lateral river migration, stabilize banks, and promote aquatic habitat, shallow transverse flow training structures such as rock vanes and stream barbs lack quantitative design guidelines. Due to the lack of fundamental knowledge about the interaction of the flow field with the sediment bed, existing engineering standards are typically based on various subjective criteria or on cross-sectionally-averaged shear stresses rather than local values. Here, we examine the performance and stability of in-stream structures within a field-scale single-threaded sand-bed meandering stream channel in the newly developed Outdoor StreamLab (OSL) at the St. Anthony Falls Laboratory (SAFL). Before and after the installation of a rock vane along the outer bank of the middle meander bend, high-resolution topography data were obtained for the entire 50-m-long reach at 1-cm spatial scale in the horizontal and sub-millimeter spatial scale in the vertical. In addition, detailed measurements of flow and turbulence were obtained using acoustic Doppler velocimetry at twelve cross-sections focused on the vicinity of the structure. Measurements were repeated at a range of extreme events, including in-bank flows with an approximate flow rate of 44 L/s (1.4 cfs) and bankfull floods with an approximate flow rate of 280 L/s (10 cfs). Under both flow rates, the structure reduced near-bank shear stresses and resulted in both a deeper thalweg and near-bank aggradation. The resulting comprehensive dataset has been used to validate a large eddy simulation carried out by SAFL’s computational fluid dynamics model, the Virtual StreamLab (VSL). This versatile computational framework is able to efficiently simulate 3D unsteady turbulent flows in natural streams with complex in-stream structures and as a result holds promise for the development of much-needed quantitative design guidelines.

  9. Rock stream stability structures in the vicinity of bridges.

    Science.gov (United States)

    2014-10-01

    This report was sponsored by the Utah Department of Transportation (UDOT) to determine if rock stream stability structures could be used as : scour countermeasures and to protect streambanks. Traditional scour countermeasures, such as rock riprap, ar...

  10. Upland and in-stream controls on baseflow nutrient dynamics in tile-drained agroecosystem watersheds

    Science.gov (United States)

    Ford, William I.; King, Kevin; Williams, Mark R.

    2018-01-01

    In landscapes with low residence times (e.g., rivers and reservoirs), baseflow nutrient concentration dynamics during sensitive timeframes can contribute to deleterious environmental conditions downstream. This study assessed upland and in-stream controls on baseflow nutrient concentrations in a low-gradient, tile-drained agroecosystem watershed. We conducted time-series analysis using Empirical mode decomposition of seven decade-long nutrient concentration time-series in the agricultural Upper Big Walnut Creek watershed (Ohio, USA). Four tributaries of varying drainage areas and three main-stem sites were monitored, and nutrient grab samples were collected weekly from 2006 to 2016 and analyzed for dissolved reactive phosphorus (DRP), nitrate-nitrogen (NO3-N), total nitrogen (TN), and total phosphorus (TP). Statistically significant seasonal fluctuations were compared with seasonality of baseflow, watershed characteristics (e.g., tile-drain density), and in-stream water quality parameters (pH, DO, temperature). Findings point to statistically significant seasonality of all parameters with peak P concentrations in summer and peak N in late winter-early spring. Results suggest that upland processes exert strong control on DRP concentrations in the winter and spring months, while coupled upland and in-stream conditions control watershed baseflow DRP concentrations during summer and early fall. Conversely, upland flow sources driving streamflow exert strong control on baseflow NO3-N, and in-stream attenuation through transient and permanent pathways impacts the magnitude of removal. Regarding TN and TP, we found that TN was governed by NO3-N, while TP was governed by DRP in summer and fluvial erosion of P-rich benthic sediments during higher baseflow conditions. Findings of the study highlight the importance of coupled in-stream and upland management for mitigating eutrophic conditions during environmentally sensitive timeframes.

  11. Combining catchment and instream modelling to assess physical habitat quality

    DEFF Research Database (Denmark)

    Olsen, Martin

    Study objectives After the implementation of EU's Water Framework Directive (WFD) in Denmark ecological impacts from groundwater exploitation on surface waters has to receive additional consideration. Small streams in particular are susceptible to changes in run-off but have only recieved little...... attention in past studies of run-off impact on the quality of stream physical habitats. This study combined catchment and instream models with instream habitat observations to assess the ecological impacts from groundwater exploitation on a small stream. The main objectives of this study was; • to assess...... which factors are controlling the run-off conditions in stream Ledreborg and to what degree • to assess the run-off reference condition of stream Ledreborg where intensive groundwater abstraction has taken place in 67 years using a simple rainfall-run-off-model • to assess how stream run-off affect...

  12. Theoretical Calculation and Analysis on the Composite Rock-Bolt Bearing Structure in Burst-Prone Ground

    Directory of Open Access Journals (Sweden)

    Liang Cheng

    2015-01-01

    Full Text Available Given the increase in mining depth and intensity, tunnel failure as a result of rock burst has become an important issue in the field of mining engineering in China. Based on the Composite Rock-Bolt Bearing Structure, which is formed due to the interaction of the bolts driven into the surrounding rock, this paper analyzes a rock burst prevention mechanism, establishes a mechanical model in burst-prone ground, deduces the strength calculation formula of the Composite Rock-Bolt Bearing Structure in burst-prone ground, and confirms the rock burst prevention criterion of the Composite Rock-Bolt Bearing Structure. According to the rock burst prevention criterion, the amount of the influence on rock burst prevention ability from the surrounding rock parameters and bolt support parameters is discussed.

  13. In-stream biogeochemical processes of a temporary river.

    Science.gov (United States)

    Tzoraki, Ourania; Nikolaidis, Nikolaos P; Amaxidis, Yorgos; Skoulikidis, Nikolaos Th

    2007-02-15

    A reach at the estuary of Krathis River in Greece was used to assess how in-stream processes alter its hydrologic and biogeochemical regime. Krathis River exhibited high annual flow variability and its transmission losses become significant, especially during the dry months. These transmission losses are enhanced in chemistry due to release of nutrients from river sediments. These fluxes are significant because they correspond to 11% of the dissolved inorganic nitrogen flux of the river. Release of nitrogen species was influenced by temperature, while release of phosphate was not because phosphate levels were below the equilibrium concentration. There is a significant amount of sediments with fine composition that create "hot spot" areas in the river reach. These sediments are mobilized during the first flush events in the fall carrying with them a significant load of nutrient and suspended matter to the coastal zone. The nutrient organic content of sediments was also significant and it was studied in terms of its mineralization capacity. The capacity for mineralization was influenced by soil moisture, exhibiting significant capacity even at moisture levels of 40%. Temporary rivers are sensitive ecosystems, vulnerable to climate changes. In-stream processes play a significant role in altering the hydrology and biogeochemistry of the water and its impacts to the coastal zone.

  14. Instream Large Wood: Dentrification Hotspots With Low N2O Production

    Science.gov (United States)

    The maintenance and restoration of forested riparian cover is important for watershed nitrogen (N) cycling. Forested riparian zones provide woody debris to streams that may stimulate in-stream denitrification and nitrous oxide (N2O) production. We examined the effects of woody an...

  15. Quantifying in-stream retention of nitrate at catchment scales using a practical mass balance approach.

    Science.gov (United States)

    Schwientek, Marc; Selle, Benny

    2016-02-01

    As field data on in-stream nitrate retention is scarce at catchment scales, this study aimed at quantifying net retention of nitrate within the entire river network of a fourth-order stream. For this purpose, a practical mass balance approach combined with a Lagrangian sampling scheme was applied and seasonally repeated to estimate daily in-stream net retention of nitrate for a 17.4 km long, agriculturally influenced, segment of the Steinlach River in southwestern Germany. This river segment represents approximately 70% of the length of the main stem and about 32% of the streambed area of the entire river network. Sampling days in spring and summer were biogeochemically more active than in autumn and winter. Results obtained for the main stem of Steinlach River were subsequently extrapolated to the stream network in the catchment. It was demonstrated that, for baseflow conditions in spring and summer, in-stream nitrate retention could sum up to a relevant term of the catchment's nitrogen balance if the entire stream network was considered.

  16. Study on structural plane characteristics of deep rock mass based on acoustic borehole TV

    International Nuclear Information System (INIS)

    Wang Xiyong; Su Rui; Chen Liang; Tian Xiao

    2014-01-01

    Deep rock mass structural plane characteristics are one of the basic data for evaluating the quality of rock mass. Based on acoustic borehole TV, the structural plane quantity, density, attitude, dominant set, structural plane aperture of deep rock mass in boreholes BS15 # and BS16 # located in Beishan granite rock mass of Gansu Province have been calculated and compared with the results of geological documentation of drill core. The results indicate that acoustic borehole TV has the effect in study on characteristics of structural plane. But as a kind of technique of geophysical logging, the acoustic borehole TV has certain defect, and need to combine with the analysis of the other geological materials in applications. (authors)

  17. Structural bursts produced by high energy muons in the rock

    International Nuclear Information System (INIS)

    Honda, K.; Takahashi, T.; Teramoto, Y.; Higashi, S.; Ozaki, S.

    1975-01-01

    Lateral structures of bursts produced by high energy muons in the rock have been observed at a depth 30 mw. e. underground by use of two layers of proportional counters. The running times were 7940 hr. The number of structural bursts observed, which have two cores in the both layers ( 1 >= 200, N 2 >= 20 particles) is 110, 1.6% of total events. These structural bursts have two types; 1) incident directions of two cores are parallel, 2) two cores intersect in the rock within 2 m above the roof of the tunnel. The events of this 2) type have large transverse momentum. (orig.) [de

  18. The peculiarities of structurizing enclosing rock massif while developing a coal seam

    Science.gov (United States)

    Kozyreva, E. N.; Shinkevich, M. V.

    2017-09-01

    Different concepts of the development of geo-mechanical processes during longwall mining of a seam which are fundamentally different from the conventional ones are introduced in the article. Fundamental principles of the model for structurizing enclosing rock mass while longwall mining along the strike are described. The model was developed on the bases of non-linear geomechanical laws. According to the model, rock mass in the area of mining operation is organized as rock geomechanical layers with shifting arches. And the formation period of shifting arches in disintegrated rock mass is divisible by the length of the stope. Undulate characteristic of a massif as a peculiarity of man-made structurization of a massif is defined. It is shown that structuring the broken massif causes the formation of block-structured system and it can be detected while monitoring the ground pressure in powered support props. The results of the research allow decreasing the negative influence of a ground pressure and can be applied to specify parameters for controlling the roof, defining geometrical dimensions of a mining section and positioning of holing chute (face entry).

  19. Theoretical Calculation and Analysis on the Composite Rock-Bolt Bearing Structure in Burst-Prone Ground

    OpenAIRE

    Cheng, Liang; Zhang, Yidong; Ji, Ming; Cui, Mantang; Zhang, Kai; Zhang, Minglei

    2015-01-01

    Given the increase in mining depth and intensity, tunnel failure as a result of rock burst has become an important issue in the field of mining engineering in China. Based on the Composite Rock-Bolt Bearing Structure, which is formed due to the interaction of the bolts driven into the surrounding rock, this paper analyzes a rock burst prevention mechanism, establishes a mechanical model in burst-prone ground, deduces the strength calculation formula of the Composite Rock-Bolt Bearing Structur...

  20. Instream sand and gravel mining: Environmental issues and regulatory process in the United States

    Science.gov (United States)

    Meador, M.R.; Layher, A.O.

    1998-01-01

    Sand and gravel are widely used throughout the U.S. construction industry, but their extraction can significantly affect the physical, chemical, and biological characteristics of mined streams. Fisheries biologists often find themselves involved in the complex environmental and regulatory issues related to instream sand and gravel mining. This paper provides an overview of information presented in a symposium held at the 1997 midyear meeting of the Southern Division of the American Fisheries Society in San Antonio, Texas, to discuss environmental issues and regulatory procedures related to instream mining. Conclusions from the symposium suggest that complex physicochemical and biotic responses to disturbance such as channel incision and alteration of riparian vegetation ultimately determine the effects of instream mining. An understanding of geomorphic processes can provide insight into the effects of mining operations on stream function, and multidisciplinary empirical studies are needed to determine the relative effects of mining versus other natural and human-induced stream alterations. Mining regulations often result in a confusing regulatory process complicated, for example, by the role of the U.S. Army Corps of Engineers, which has undergone numerous changes and remains unclear. Dialogue among scientists, miners, and regulators can provide an important first step toward developing a plan that integrates biology and politics to protect aquatic resources.

  1. A numerical study on the structural behavior of underground rock caverns for radioactive waste disposal

    International Nuclear Information System (INIS)

    Kim, Sun Hoon; Choi, Kyu Sup; Lee, Kyung Jin; Kim, Dae Hong

    1991-01-01

    In order to design safe and economical underground disposal structures for radioactive wastes, understanding the behavior of discontinuous rock masses is essential. This study includes discussions about the computational model for discontinuous rock masses and the structural analysis method for underground storage structures. Then, based on an engineering judgement a suitable selection and slight modifications on computational models and analysis methods have been made in order to analyze and understand the structural behavior of the rock cavern with discontinuities

  2. A statistical model for porous structure of rocks

    Institute of Scientific and Technical Information of China (English)

    JU Yang; YANG YongMing; SONG ZhenDuo; XU WenJing

    2008-01-01

    The geometric features and the distribution properties of pores in rocks were In-vestigated by means of CT scanning tests of sandstones. The centroidal coordl-nares of pores, the statistic characterristics of pore distance, quantity, size and their probability density functions were formulated in this paper. The Monte Carlo method and the random number generating algorithm were employed to generate two series of random numbers with the desired statistic characteristics and prob-ability density functions upon which the random distribution of pore position, dis-tance and quantity were determined. A three-dimensional porous structural model of sandstone was constructed based on the FLAC3D program and the information of the pore position and distribution that the series of random numbers defined. On the basis of modelling, the Brazil split tests of rock discs were carried out to ex-amine the stress distribution, the pattern of element failure and the inoaculation of failed elements. The simulation indicated that the proposed model was consistent with the realistic porous structure of rock in terms of their statistic properties of pores and geometric similarity. The built-up model disclosed the influence of pores on the stress distribution, failure mode of material elements and the inosculation of failed elements.

  3. A statistical model for porous structure of rocks

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The geometric features and the distribution properties of pores in rocks were in- vestigated by means of CT scanning tests of sandstones. The centroidal coordi- nates of pores, the statistic characterristics of pore distance, quantity, size and their probability density functions were formulated in this paper. The Monte Carlo method and the random number generating algorithm were employed to generate two series of random numbers with the desired statistic characteristics and prob- ability density functions upon which the random distribution of pore position, dis- tance and quantity were determined. A three-dimensional porous structural model of sandstone was constructed based on the FLAC3D program and the information of the pore position and distribution that the series of random numbers defined. On the basis of modelling, the Brazil split tests of rock discs were carried out to ex- amine the stress distribution, the pattern of element failure and the inosculation of failed elements. The simulation indicated that the proposed model was consistent with the realistic porous structure of rock in terms of their statistic properties of pores and geometric similarity. The built-up model disclosed the influence of pores on the stress distribution, failure mode of material elements and the inosculation of failed elements.

  4. Analysis of effects of geological structures in rock driving by TBM

    Directory of Open Access Journals (Sweden)

    Ľudmila Tréfová

    2006-12-01

    Full Text Available Although mechanical properties belongs to important parameter for the excavation modelling, effect of geological structures on the rock massive fragmentation is often much higher than varying rock properties. This paper deals with the analysis of geological structures. It is focused on the schistosity orientation towards the tunnel azimuth. The aim is to define of schistosity effect on the penetration rate. It is a basis creating of fuzzy rules for the performance model full-profile tunnel boring machine

  5. Effects of watershed and in-stream liming on macroinvertebrate communities in acidified tributaries to an Adirondack lake

    Science.gov (United States)

    George, Scott D.; Baldigo, Barry P.; Lawrence, Gregory B.; Fuller, Randall L.

    2018-01-01

    Liming techniques are being explored as a means to accelerate the recovery of aquatic biota from decades of acid deposition in many regions. The preservation or restoration of native sportfish populations has typically been the impetus for liming programs, and as such, less attention has been given to its effects on other biological assemblages such as macroinvertebrates. Furthermore, the differing effects of various lime application strategies such as in-stream and watershed applications are not well understood. In 2012, a program was initiated using in-stream and aerial (whole-watershed) liming to improve water quality and Brook Trout (Salvelinus fontinalis) recruitment in three acidified tributaries of a high-elevation Adirondack lake in New York State. Concurrently, macroinvertebrates were sampled annually between 2013 and 2016 at 3 treated sites and 3 untreated reference sites to assess the effects of each liming technique on this community. Despite improvements in water chemistry in all three limed streams, our results generally suggest that neither liming technique succeeded in improving the condition of macroinvertebrate communities. The watershed application caused an immediate and unsustained decrease in the density of macroinvertebrates and increase in the proportion of sensitive taxa. These changes were driven primarily by a one-year 71 percent reduction of the acid-tolerant Leuctra stoneflies and likely represent an initial chemistry shock from the lime application rather than a recovery response. The in-stream applications appeared to reduce the density of macroinvertebrates, particularly in one stream where undissolved lime covered the natural substrate. The close proximity of our study sites to the in-stream application points (50 and 1230 m) may partly explain these negative effects. Our results are consistent with prior studies of in-stream liming which indicate that this technique often fails to restore macroinvertebrate communities to a pre

  6. Storm and hurricane disturbances on phosphorus storage within an in-stream wetland

    Science.gov (United States)

    The ability of wetlands to hold phosphorus (P) makes them and important landscape feature that help to protect water quality. However, their ability to retain P can be affected through hydrologic disturbances caused by both storms and flooding. An animal waste impacted in-stream wetland (ISW) locate...

  7. Land use/land cover and scale influences on in-stream nitrogen uptake kinetics

    Science.gov (United States)

    Covino, Tim; McGlynn, Brian; McNamara, Rebecca

    2012-06-01

    Land use/land cover change often leads to increased nutrient loading to streams; however, its influence on stream ecosystem nutrient transport remains poorly understood. Given the deleterious impacts elevated nutrient loading can have on aquatic ecosystems, it is imperative to improve understanding of nutrient retention capacities across stream scales and watershed development gradients. We performed 17 nutrient addition experiments on six streams across the West Fork Gallatin Watershed, Montana, USA, to quantify nitrogen uptake kinetics and retention dynamics across stream sizes (first to fourth order) and along a watershed development gradient. We observed that stream nitrogen (N) uptake kinetics and spiraling parameters varied across streams of different development intensity and scale. In more developed watersheds we observed a fertilization affect. This fertilization affect was evident as increased ash-free dry mass, chlorophylla, and ambient and maximum uptake rates in developed as compared to undeveloped streams. Ash-free dry mass, chlorophylla, and the number of structures in a subwatershed were significantly correlated to nutrient spiraling and kinetic parameters, while ambient and average annual N concentrations were not. Additionally, increased maximum uptake capacities in developed streams contributed to low in-stream nutrient concentrations during the growing season, and helped maintain watershed export at low levels during base flow. Our results indicate that land use/land cover change can enhance in-stream uptake of limiting nutrients and highlight the need for improved understanding of the watershed dynamics that control nutrient export across scales and development intensities for mitigation and protection of aquatic ecosystems.

  8. Effect of Micro-Structure on Fatigue Behavior of Intact Rocks under Completely Reversed Loading

    Directory of Open Access Journals (Sweden)

    Saeed Jamali Zavareh

    2017-01-01

    Full Text Available Rock formations and structures can be subjected to both static and dynamic loadings. Static loadings resulting from different sources such as gravity and tectonic forces and dynamic forces are intermittently transmitted via vibrations of the earth’s crust, through major earthquakes, rock bursts, rock blasting and drilling and also, traffic. Reaction of rocks to cyclic and repetitive stresses resulting from dynamic loads has been generally neglected with the exception of a few rather limited studies. In this study, , two crystalline quarry stones in Iran; (Natanz gabbro and Green onyx and one non-crystalline rock (Asmari limestone are used to evaluate the effect of micro-structure of intact rock on fatigue behavior. These rocks have different mineral compositions and formation conditions. A new apparatus based on rotating beam fatigue testing machine (R.R.Moore, which is commonly used for laboratory fatigue test in metals, is developed and fatigue behavior and existence of the endurance limit were evaluated for the mentioned rocks based on stress-life method. The obtained results in the variation of applied amplitude stress versus loading cycle number (S-N diagram followed common relationship in other materials. In addition, the endurance limit is perceived for all tested rocks. The results also illustrated that the endurance limits for all types of tested rocks in this study are ranged between 0.4 and 0.6 of their tensile strengths. The endurance limit to tensile strength fraction of green onyx and Natanz gabbro were approximated in a higher value compared to the Asmari limestone with non-crystalline micro-structure.

  9. Multiple Approaches to Characterizing Pore Structure in Natural Rock

    Science.gov (United States)

    Hu, Q.; Dultz, S.; Hamamoto, S.; Ewing, R. P.

    2012-12-01

    Microscopic characteristics of porous media - pore shape, pore-size distribution, and pore connectivity - control fluid flow and chemical transport, and are important in hydrogeological studies of rock formations in the context of energy, environmental, and water resources management. This presentation discusses various approaches to investigating pore structure of rock, with a particular focus on the Barnett Shale in north Texas used for natural gas production. Approaches include imbibition, tracer diffusion, porosimetry (MIP, vapor adsorption/desorption isotherms, NMR cyroporometry), and imaging (μ-tomography, Wood's metal impregnation, FIB/SEM). Results show that the Barnett Shale pores are predominantly in the nm size range, with a measured median pore-throat diameter of 6.5 nm. But small pore size is not the major contributor to low gas recovery; rather, the low gas diffusivity appears to be caused by low pore connectivity. Chemical diffusion in sparsely-connected pore spaces is not well described by classical Fickian behavior; anomalous behavior is suggested by percolation theory, and confirmed by results of imbibition tests. Our evolving complementary approaches, with their several advantages and disadvantages, provide a rich toolbox for tackling the pore structure characteristics in the Barnett Shale and other natural rocks.

  10. Prehistoric Rock Structures of the Idaho National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Brenda R Pace

    2007-04-01

    Over the past 13,500 years, human populations have lived in and productively utilized the natural resources offered by the cold desert environment of the northeastern Snake River Plain in eastern Idaho. Within an overall framework of hunting and gathering, groups relied on an intimate familiarity with the natural world and developed a variety of technologies to extract the resources that they needed to survive. Useful items were abundant and found everywhere on the landscape. Even the basaltic terrain and the rocks, themselves, were put to productive use. This paper presents a preliminary classification scheme for rock structures built on the Idaho National Laboratory landscape by prehistoric aboriginal populations, including discussions of the overall architecture of the structures, associated artifact assemblages, and topographic placement. Adopting an ecological perspective, the paper concludes with a discussion of the possible functions of these unique resources for the desert populations that once called the INL home.

  11. Carbonate Melt Rocks from the Haughton Impact Structure, Devon Island, Nunavut, Canada

    Science.gov (United States)

    Osinski, G. R.; Spray, J. G.; Lee, P.

    2002-01-01

    The target rocks at the Haughton impact structure, Canada, are predominantly carbonates. The well preserved allochthonous crater-fill deposits are reinterpreted here as being carbonatitic impact melt rocks. The implications of our findings will be discussed. Additional information is contained in the original extended abstract.

  12. Instream wood in a steep headwater channel: geomorphic significance of large and small wood

    Science.gov (United States)

    Galia, Tomáš; Šilhán, Karel; Ruiz-Villanueva, Virginia; Tichavský, Radek

    2016-04-01

    Besides the well-known significance of large wood (LW), also small woody pieces (SW; here defined as pieces with dimensions at least 0.5 m length and 0.05 m diameter), can play an important role in steep narrow headwaters. We inventoried instream wood in the 0.4 km long Mazák headwater channel, Moravskoslezské Beskydy Mts, Czech Republic (2pieces were European beeches (Fagus sylvatica L.); only two pieces were Norway spruces (Picea abies (L.) Karst.). First results showed an increase in the number of LWs in channel-reaches confined by the steepest adjacent hillslopes (especially at 0.15-0.20 km). Increasing downstream amount of SW most likely reflected transport processes in the stream, and the later deposition of SWs on the lowest channel gradients. Also LWs and SWs in the downstream channel-reaches were more decayed than wood presented in the upper reaches. The orientation of instream wood was connected with its length and stability, and LWs longer than 5 m were usually attached to adjacent hillslopes. Pieces longer than 2 m, which were unattached or were somehow stabilized in the channel bed, had often orientation of 0° or 337°. LWs were mostly unattached in the upstream channel-reaches, while often stabilized by adjacent hillslopes in the middle part. At 0.05-0.10 km, there were also many logs stabilized by bed sediments. By contrast, SWs were mostly unattached in the whole longitudinal profile. We observed higher % of influenced channel width by SWs than LWs. Also, SWs were usually entirely located in the channel, which was significantly different when compared to LWs. Nine small steps (step height ~0.5 m) were created by instream wood; six of them were formed by SWs. Dendrogeomorphic cross dating supported the observed decay status for LW/SW within the longitudinal profile: at the lowest channel gradients with wider higher active channels, the potential for storage of instream wood increased. In these downstream reaches we observed older LW and SW, with

  13. The effect of in-stream activities on the Njoro River, Kenya. Part I: Stream flow and chemical water quality

    Science.gov (United States)

    Yillia, Paul T.; Kreuzinger, Norbert; Mathooko, Jude M.

    For shallow streams in sub-Saharan Africa, in-stream activities could be described as the actions by people and livestock, which take place within or besides stream channels. This study examined the nature of in-stream activities along a rural stream in Kenya and established the inequality in water allocation for various livelihood needs, as well as the negative impact they have on dry weather stream flow and chemical water quality. Seven locations along the stream were studied in wet and dry weather of 2006. Enumeration consisted of making head counts of people and livestock and tallying visitors at hourly intervals from 6 a.m. to 7 p.m. To estimate water abstraction, filled containers of known volume were counted and the stream was sampled to examine the impact on water quality. Water samples were obtained upstream and downstream of in-stream activities before (6 a.m.) and during (11 a.m., 6 p.m.) activities. Samples were analyzed for suspended solids, turbidity, BOD 5, total nitrogen and total phosphorus. The daily total abstraction at the middle reaches during dry weather was 120-150 m 3 day -1. More than 60% of abstraction was done by water vendors. Vended water from the stream was sold at US 3.5-7.5 per m 3 and vendors earned between US 3-6 a day. Abstracted water contributed approximately 40-60% of the total daily consumptive water use in the riparian area during dry weather but >30% of the morning stream flow was abstracted thereby upsetting stream flow in the lower reaches. The daily total water abstraction correlated positively ( R2, 0.98) and significantly ( p < 0.05) with the daily total human visit, which was diurnally periodic with two peaks, occurring between 9 a.m. and 10 a.m. and from 4 p.m. to 5 p.m. This diurnal pattern of visits and the corresponding in-stream activities affected water quality. In particular, suspended solids, turbidity and BOD 5 levels increased significantly ( p < 0.05) downstream during in-stream activities. It was concluded

  14. In-stream Physical Heterogeneity, Rainfall Aided Flushing, and Discharge on Stream Water Quality.

    Science.gov (United States)

    Gomes, Pattiyage I A; Wai, Onyx W H

    2015-08-01

    Implications of instream physical heterogeneity, rainfall-aided flushing, and stream discharge on water quality control have been investigated in a headwater stream of a climatic region that has contrasting dry and wet seasons. Dry (low flow) season's physical heterogeneity showed a positive correlation with good water quality. However, in the wet season, physical heterogeneity showed minor or no significance on water quality variations. Furthermore, physical heterogeneity appeared to be more complementary with good water quality subsequent to rainfall events. In many cases stream discharge was a reason for poor water quality. For the dry season, graywater inputs to the stream could be held responsible. In the wet season, it was probably the result of catchment level disturbances (e.g., regulation of ephemeral freshwater paths). Overall, this study revealed the importance of catchment-based approaches on water quality improvement in tandem with in-stream approaches framed on a temporal scale.

  15. In situ determination of the dynamic properties of thinly-layered rock to evaluate rock-structure interaction at a nuclear power plant site

    International Nuclear Information System (INIS)

    Johnson, William J.; Rizzo, Paul C.

    1988-01-01

    The presence of layers of weak sedimentary rock in a column of otherwise competent rock can significantly affect the seismic response of nuclear power plant structures due to rock-structure interaction effects. The determination of the dynamic properties of thinly-layered rock is, however, difficult. When borings are placed close enough to allow for a characterization of refracted waves, other potential problems such as the identification of clear P- and S-wave arrivals, extremely short duration of records, near-field waves, instrumental stability, and overall record resolution become magnified. Other problems such as cultural noise and signal amplitude can become critical when high resolution is required. Conventional storage oscilloscopes and seismographs are inadequate under these conditions, but modern digital recording systems with the application of stringent calibration and recording procedures can yield successful results. A case history of a high-precision cross-hole survey to a depth of 150 meters in thinly-bedded sedimentary rock at a nuclear power plant site is presented in order to illustrate the systems and procedures necessary to obtain successful results under adverse conditions. (author)

  16. Structural and kinematic analysis from Montevideo Formation rocks

    International Nuclear Information System (INIS)

    Masquelin, E.; Gutierrez, L.; Sienra, M.

    2004-01-01

    The main purpose of this work is to bring new advances about structural and kinematic analysis from Montevideo Formation rocks. This information was collected by means of the classic methodology used for metamorphic terrains: (i) to recognize the nature of the protoliths, (ii) to discriminate the diversity of intrusive rocks and their relative age, (iii) to evaluate the intensity of strain, and (iv) to find the relationship between this strain and related displacements, in accordance to the unified theory for ductile shear zones. The exposed results show that there are not enough evidences to prove that the layering found in para-amphibolites and para-gneisses is the bedding surface. Although various lava primary structures were presented, these structures do not bring the bedding plane directly, and sedimentary structures are suspicious. In the other hand, the strain has proved to be very intense, by the development of isoclinal folds (may be intrafolial), highly strained veins of plagioclase-bearing gneiss and the boudinage of the duplicated sequence parallel to the axes of D2 later folds. The D2 fold axes parallel direction could be acted as the transport direction of a major strike-slip shear zone, striking N70 0 E. The fact is that various ductile flow vorticity indicators were found in para-amphibolites showing a dextral shear sense [es

  17. Geo-structural modelling for potential large rock slide in Machu Picchu

    Science.gov (United States)

    Spizzichino, D.; Delmonaco, G.; Margottini, C.; Mazzoli, S.

    2009-04-01

    The monumental complex of the Historical Sanctuary of Machu Picchu, declared as World Heritage Site by UNESCO in 1983, is located in the Andean chain at approx. 80 km from Cuzco (Peru) and at an elevation of 2430 m a.s.l. along the Urubamba River Valley. From a geological point of view, the Machu Picchu granitoid pluton, forming part of the larger "Quillabamba granite", is one of a series of plutons intruded along the axial zone of the high Eastern Cordillera Permo-Liassic rift system including a variety of rock types, dominantly granites and granodiorites. The most evident structures at the outcrop scale consist of planar joint sets that may be variably reactivated and exhibiting 4 main orientations. At present, the site is affected by geological risk due to frequent landslides that threaten security and tourist exploitation. In the last years, the international landslide scientific community has promoted a multi-discipline joint programme mainly finalised to slope deformation monitoring and analysis after the warning, launched in 2001, of a potential collapse of the citadel, caused by a huge rock slide. The contribute of the Italian research team was devoted to implement a landslide risk analysis and an innovative remote sensing techniques. The main scope of this work is to present the implementation of a geo-structural modelling aimed at defining present and potential slope stability conditions of the Machu Picchu Citadel. Data have been collected by geological, structural and geomechanical field surveys and laboratory tests in order to reconstruct the geomorphological evolution of the area. Landslide types and evolution are strictly controlled by regional tectonic uplift and structural setting. Several slope instability phenomena have been identified and classified according to mechanism, material involved and state of activity. Rock falls, debris flows, rock slides and debris slides are the main surveyed landslide types. Rock slides and rock falls may produce

  18. Links between riparian landcover, instream environment and fish assemblages in headwater streams of south-eastern Brazil

    Science.gov (United States)

    Cruz, Bruna B.; Miranda, Leandro E.; Cetra, Mauricio

    2013-01-01

    We hypothesised and tested a hierarchical organisation model where riparian landcover would influence bank composition and light availability, which in turn would influence instream environments and control fish assemblages. The study was conducted during the dry season in 11 headwater tributaries of the Sorocaba River in the upper Paraná River Basin, south-eastern Brazil. We focused on seven environmental factors each represented by one or multiple environmental variables and seven fish functional traits each represented by two or more classes. Multivariate direct gradient analyses suggested that riparian zone landcover can be considered a higher level causal factor in a network of relations that control instream characteristics and fish assemblages. Our results provide a framework for a hierarchical conceptual model that identifies singular and collective influences of variables from different scales on each other and ultimately on different aspects related to stream fish functional composition. This conceptual model is focused on the relationships between riparian landcover and instream variables as causal factors on the organisation of stream fish assemblages. Our results can also be viewed as a model for headwater stream management in that landcover can be manipulated to influence factors such as bank composition, substrates and water quality, whereas fish assemblage composition can be used as indicators to monitor the success of such efforts.

  19. Magnetic coupling at perovskite and rock-salt structured interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Matvejeff, M., E-mail: mikko.matvejeff@picosun.com [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8581 Chiba (Japan); Department of Chemistry, Aalto University, Kemistintie 1, 02150 Espoo (Finland); Ahvenniemi, E. [Department of Chemistry, Aalto University, Kemistintie 1, 02150 Espoo (Finland); Takahashi, R.; Lippmaa, M. [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8581 Chiba (Japan)

    2015-10-05

    We study magnetic coupling between hole-doped manganite layers separated by either a perovskite or a rock-salt barrier of variable thickness. Both the type and the quality of the interface have a strong impact on the minimum critical barrier thickness where the manganite layers become magnetically decoupled. A rock-salt barrier layer only 1 unit cell (0.5 nm) thick remains insulating and is able to magnetically de-couple the electrode layers. The technique can therefore be used for developing high-performance planar oxide electronic devices such as magnetic tunnel junctions and quantum well structures that depend on magnetically and electronically sharp heterointerfaces.

  20. Using high-frequency nitrogen and carbon measurements to decouple temporal dynamics of catchment and in-stream transport and reaction processes in a headwater stream

    Science.gov (United States)

    Blaen, P.; Riml, J.; Khamis, K.; Krause, S.

    2017-12-01

    Within river catchments across the world, headwater streams represent important sites of nutrient transformation and uptake due to their high rates of microbial community processing and relative abundance in the landscape. However, separating the combined influence of in-stream transport and reaction processes from the overall catchment response can be difficult due to spatio-temporal variability in nutrient and organic matter inputs, flow regimes, and reaction rates. Recent developments in optical sensor technologies enable high-frequency, in situ nutrient measurements, and thus provide opportunities for greater insights into in-stream processes. Here, we use in-stream observations of hourly nitrate (NO3-N), dissolved organic carbon (DOC) and dissolved oxygen (DO) measurements from paired in situ sensors that bound a 1 km headwater stream reach in a mixed-use catchment in central England. We employ a spectral approach to decompose (1) variances in solute loading from the surrounding landscape, and (2) variances in reach-scale in-stream nutrient transport and reaction processes. In addition, we estimate continuous rates of reach-scale NO3-N and DOC assimilation/dissimilation, ecosystem respiration and primary production. Comparison of these results over a range of hydrological conditions (baseflow, variable storm events) and timescales (event-based, diel, seasonal) facilitates new insights into the physical and biogeochemical processes that drive in-stream nutrient dynamics in headwater streams.

  1. Modeling In-stream Tidal Energy Extraction and Its Potential Environmental Impacts

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea; Geerlofs, Simon H.

    2014-09-30

    In recent years, there has been growing interest in harnessing in-stream tidal energy in response to concerns of increasing energy demand and to mitigate climate change impacts. While many studies have been conducted to assess and map tidal energy resources, efforts for quantifying the associated potential environmental impacts have been limited. This paper presents the development of a tidal turbine module within a three-dimensional unstructured-grid coastal ocean model and its application for assessing the potential environmental impacts associated with tidal energy extraction. The model is used to investigate in-stream tidal energy extraction and associated impacts on estuarine hydrodynamic and biological processes in a tidally dominant estuary. A series of numerical experiments with varying numbers and configurations of turbines installed in an idealized estuary were carried out to assess the changes in the hydrodynamics and biological processes due to tidal energy extraction. Model results indicated that a large number of turbines are required to extract the maximum tidal energy and cause significant reduction of the volume flux. Preliminary model results also indicate that extraction of tidal energy increases vertical mixing and decreases flushing rate in a stratified estuary. The tidal turbine model was applied to simulate tidal energy extraction in Puget Sound, a large fjord-like estuary in the Pacific Northwest coast.

  2. Structural Analysis: Folds Classification of metasedimentary rock in the Peninsular Malaysia

    Science.gov (United States)

    Shamsuddin, A.

    2017-10-01

    Understanding shear zone characteristics of deformation are a crucial part in the oil and gas industry as it might increase the knowledge of the fracture characteristics and lead to the prediction of the location of fracture zones or fracture swarms. This zone might give high influence on reservoir performance. There are four general types of shear zones which are brittle, ductile, semibrittle and brittle-ductile transition zones. The objective of this study is to study and observe the structural geometry of the shear zones and its implication as there is a lack of understanding, especially in the subsurface area because of the limitation of seismic resolution. A field study was conducted on the metasedimentary rocks (shear zone) which are exposed along the coastal part of the Peninsular Malaysia as this type of rock resembles the types of rock in the subsurface. The analysis in this area shows three main types of rock which are non-foliated metaquartzite and foliated rock which can be divided into slate and phyllite. Two different fold classification can be determined in this study. Layer 1 with phyllite as the main type of rock can be classified in class 1C and layer 2 with slate as the main type of rock can be classified in class 1A. This study will benefit in predicting the characteristics of the fracture and fracture zones.

  3. Rock Pore Structure as Main Reason of Rock Deterioration

    Directory of Open Access Journals (Sweden)

    Ondrášik Martin

    2014-03-01

    Full Text Available Crashed or dimensional rocks have been used as natural construction material, decoration stone or as material for artistic sculptures. Especially old historical towns not only in Slovakia have had experiences with use of stones for construction purposes for centuries. The whole buildings were made from dimensional stone, like sandstone, limestone or rhyolite. Pavements were made especially from basalt, andesite, rhyolite or granite. Also the most common modern construction material - concrete includes large amounts of crashed rock, especially limestone, dolostone and andesite.

  4. Some new developments in the design rules for coastal structures in relation with the new Rock Manual

    OpenAIRE

    Verhagen, H.J.

    2005-01-01

    In 1991 CUR in the Netherlands and CIRIA in the UK have published the "manual on the use of rock in coastal engineering", usually referred to as the "Rock Manual". This book of 600 pages gave an overview of the state of the art regarding the design of rock structures along coasts. In 1995 CUR published a adapted version of this book, also containing information on closure works and rock structures along rivers. Although the information in these books is not outdated, there was a general feeli...

  5. Modelling Technique for Demonstrating Gravity Collapse Structures in Jointed Rock.

    Science.gov (United States)

    Stimpson, B.

    1979-01-01

    Described is a base-friction modeling technique for studying the development of collapse structures in jointed rocks. A moving belt beneath weak material is designed to simulate gravity. A description is given of the model frame construction. (Author/SA)

  6. Evaluating shallow-flow rock structures as scour countermeasures at bridges.

    Science.gov (United States)

    2009-12-01

    A study to determine whether or not shallow-flow rock structures could reliably be used at bridge abutments in place of riprap. Research was conducted in a two-phase effort beginning with numerical modeling and ending with field verification of model...

  7. In-stream attenuation of neuro-active pharmaceuticals and their metabolites

    Science.gov (United States)

    Writer, Jeffrey; Antweiler, Ronald C.; Ferrar, Imma; Ryan, Joseph N.; Thurman, Michael

    2013-01-01

    In-stream attenuation was determined for 14 neuro-active pharmaceuticals and associated metabolites. Lagrangian sampling, which follows a parcel of water as it moves downstream, was used to link hydrological and chemical transformation processes. Wastewater loading of neuro-active compounds varied considerably over a span of several hours, and thus a sampling regime was used to verify that the Lagrangian parcel was being sampled and a mechanism was developed to correct measured concentrations if it was not. In-stream attenuation over the 5.4-km evaluated reach could be modeled as pseudo-first-order decay for 11 of the 14 evaluated neuro-active pharmaceutical compounds, illustrating the capacity of streams to reduce conveyance of neuro-active compounds downstream. Fluoxetine and N-desmethyl citalopram were the most rapidly attenuated compounds (t1/2 = 3.6 ± 0.3 h, 4.0 ± 0.2 h, respectively). Lamotrigine, 10,11,-dihydro-10,11,-dihydroxy-carbamazepine, and carbamazepine were the most persistent (t1/2 = 12 ± 2.0 h, 12 ± 2.6 h, 21 ± 4.5 h, respectively). Parent compounds (e.g., buproprion, carbamazepine, lamotrigine) generally were more persistent relative to their metabolites. Several compounds (citalopram, venlafaxine, O-desmethyl-venlafaxine) were not attenuated. It was postulated that the primary mechanism of removal for these compounds was interaction with bed sediments and stream biofilms, based on measured concentrations in stream biofilms and a column experiment using stream sediments.

  8. Structural Color of Rock Dove’s Neck Feather

    Science.gov (United States)

    Nakamura, Eri; Yoshioka, Shinya; Kinoshita, Shuichi

    2008-12-01

    It is well known that some kinds of animal have surprisingly brilliant colors showing beautiful iridescence. These colors are called structural colors, and are thought to originate from optical interference caused by periodic microstructures that have sizes comparable with the wavelength of light. However, much larger structural modifications can also play an important role in the coloration mechanism. In this paper, we show through careful optical and structural investigations that the structural color of the neck feather of rock dove, Columba livia, has a very comprehensive mechanism: the thin-layer optical interference phenomenon fundamentally produces the iridescence, while the layer structure is accompanied by various kinds of larger-size structural modifications that control the angular range of the reflection. Further, it is found that the granules containing melanin pigment exist in a localized manner to effectively enhance the contrast of the color caused by optical interference.

  9. Thermally induced rock stress increment and rock reinforcement response

    International Nuclear Information System (INIS)

    Hakala, M.; Stroem, J.; Nujiten, G.; Uotinen, L.; Siren, T.; Suikkanen, J.

    2014-07-01

    This report describes a detailed study of the effect of thermal heating by the spent nuclear fuel containers on the in situ rock stress, any potential rock failure, and associated rock reinforcement strategies for the Olkiluoto underground repository. The modelling approach and input data are presented together repository layout diagrams. The numerical codes used to establish the effects of heating on the in situ stress field are outlined, together with the rock mass parameters, in situ stress values, radiogenic temperatures and reinforcement structures. This is followed by a study of the temperature and stress evolution during the repository's operational period and the effect of the heating on the reinforcement structures. It is found that, during excavation, the maximum principal stress is concentrated at the transition areas where the profile changes and that, due to the heating from the deposition of spent nuclear fuel, the maximum principal stress rises significantly in the tunnel arch area of NW/SW oriented central tunnels. However, it is predicted that the rock's crack damage (CD, short term strength) value of 99 MPa will not be exceeded anywhere within the model. Loads onto the reinforcement structures will come from damaged and loosened rock which is assumed in the modelling as a free rock wedge - but this is very much a worst case scenario because there is no guarantee that rock cracking would form a free rock block. The structural capacity of the reinforcement structures is described and it is predicted that the current quantity of the rock reinforcement is strong enough to provide a stable tunnel opening during the peak of the long term stress state, with damage predicted on the sprayed concrete liner. However, the long term stability and safety can be improved through the implementation of the principles of the Observational Method. The effect of ventilation is also considered and an additional study of the radiogenic heating effect on the brittle

  10. Thermally induced rock stress increment and rock reinforcement response

    Energy Technology Data Exchange (ETDEWEB)

    Hakala, M. [KMS Hakala Oy, Nokia (Finland); Stroem, J.; Nujiten, G.; Uotinen, L. [Rockplan, Helsinki (Finland); Siren, T.; Suikkanen, J.

    2014-07-15

    This report describes a detailed study of the effect of thermal heating by the spent nuclear fuel containers on the in situ rock stress, any potential rock failure, and associated rock reinforcement strategies for the Olkiluoto underground repository. The modelling approach and input data are presented together repository layout diagrams. The numerical codes used to establish the effects of heating on the in situ stress field are outlined, together with the rock mass parameters, in situ stress values, radiogenic temperatures and reinforcement structures. This is followed by a study of the temperature and stress evolution during the repository's operational period and the effect of the heating on the reinforcement structures. It is found that, during excavation, the maximum principal stress is concentrated at the transition areas where the profile changes and that, due to the heating from the deposition of spent nuclear fuel, the maximum principal stress rises significantly in the tunnel arch area of NW/SW oriented central tunnels. However, it is predicted that the rock's crack damage (CD, short term strength) value of 99 MPa will not be exceeded anywhere within the model. Loads onto the reinforcement structures will come from damaged and loosened rock which is assumed in the modelling as a free rock wedge - but this is very much a worst case scenario because there is no guarantee that rock cracking would form a free rock block. The structural capacity of the reinforcement structures is described and it is predicted that the current quantity of the rock reinforcement is strong enough to provide a stable tunnel opening during the peak of the long term stress state, with damage predicted on the sprayed concrete liner. However, the long term stability and safety can be improved through the implementation of the principles of the Observational Method. The effect of ventilation is also considered and an additional study of the radiogenic heating effect on the

  11. Experimental study on influence of carbon dioxide on porous structure and mechanical properties of shale rock

    Directory of Open Access Journals (Sweden)

    Danuta Miedzińska

    2017-12-01

    Full Text Available Shale rocks are geological formations which can be unconventional gas reservoirs. During their interaction with carbon dioxide, which can be used as a fracturing fluid in shale gas recovery process, many phenomena take place that can influence rock structure and mechanical properties. The research on changes in rock structure under super critical carbon dioxide interaction and their influence of shale properties were presented in the paper. The structural tests were carried out with the use of microscopic techniques with different resolutions of visualization. The uniaxial compression test was applied as a mechanical properties’ assessment experiment. As a result of research, some dependence was observed. The bigger decrease was in porosity after infiltration in lower zooms, the bigger increase in porosity in high zooms and mechanical properties was noticed. Keywords: geomechanics, shale rock, carbon dioxide

  12. Evaluation of ecological instream flow considering hydrological alterations in the Yellow River basin, China

    Science.gov (United States)

    Zhang, Qiang; Zhang, Zongjiao; Shi, Peijun; Singh, Vijay P.; Gu, Xihui

    2018-01-01

    The Yellow River is the second largest river in China and is the important source for water supply in the northwestern and northern China. It is often regarded as the mother river of China. Owing to climatic change and intensifying human activities, such as increasing withdrawal of water for meeting growing agricultural irrigation needs since 1986, the flow of Yellow River has decreased, with serious impacts on the ecological environment. Using multiple hydrological indicators and Flow Duration Curve (DFC)-based ecodeficit and ecosurplus, this study investigates the impact of hydrological alterations, such as the impact of water reservoirs or dams, on downstream ecological instream flow. Results indicate that: (1) due to the impoundment and hydrological regulations of water reservoirs, occurrence rates and magnitudes of high flow regimes have decreased and the decrease is also found in the magnitudes of low flow events. These changes tend to be more evident from the upper to the lower Yellow River basin; (2) human activities tend to enhance the instream flow variability, particularly after the 1980s;(3) the ecological environment in different parts of the Yellow River basin is under different degrees of ecological risk. In general, lower to higher ecological risk can be detected due to hydrological alterations from the upper to the lower Yellow River basin. This shows that conservation of ecological environment and river health is facing a serious challenge in the lower Yellow River basin; (4) ecological instream flow indices, such as ecodeficit and ecosurplus, and IHA32 hydrological indicators are in strong relationships, suggesting that ecodeficit and ecosurplus can be regarded as appropriate ecological indicators for developing measures for mitigating the adverse impact of human activities on the conservation of ecological environment in the Yellow River basin.

  13. Using a Content Management System for Integrated Water Quantity, Quality and Instream Flows Modeling

    Science.gov (United States)

    Burgholzer, R.; Brogan, C. O.; Scott, D.; Keys, T.

    2017-12-01

    With increased population and water demand, in-stream flows can become depleted by consumptive uses and dilution of permitted discharges may be compromised. Reduced flows downstream of water withdrawals may increase the violation rate of bacterial concentrations from direct deposition by livestock and wildlife. Water storage reservoirs are constructed and operated to insure more stable supplies for consumptive demands and dilution flows, however their use comes at the cost of increased evaporative losses, potential for thermal pollution, interrupted fish migration, and reduced flooding events that are critical to maintain habitat and water quality. Due to this complex interrelationship between water quantity, quality and instream habitat comprehensive multi-disciplinary models must be developed to insure long-term sustainability of water resources and to avoid conflicts between drinking water, food and energy production, and aquatic biota. The Commonwealth of Virginia funded the expansion of the Chesapeake Bay Program Phase 5 model to cover the entire state, and has been using this model to evaluate water supply permit and planning since 2009. This integrated modeling system combines a content management system (Drupal and PHP) for model input data and leverages the modularity of HSPF with the custom segmentation and parameterization routines programmed by modelers working with the Chesapeake Bay Program. The model has been applied to over 30 Virginia Water Permits, instream flows and aquatic habitat models and a Virginias 30 year water supply demand projections. Future versions will leverage the Bay Model auto-calibration routines for adding small-scale water supply and TMDL models, utilize climate change scenarios, and integrate Virginia's reservoir management modules into the Chesapeake Bay watershed model, feeding projected demand and operational changes back up to EPA models to improve the realism of future Bay-wide simulations.

  14. Meeting instream flow needs of lower Colorado River in Texas

    International Nuclear Information System (INIS)

    Martin, Q.W.

    1993-01-01

    The Lower Colorado River Authority (LCRA), an agency of the State of Texas, manages the surface waters of the lower Colorado River in Texas. The major water supply source in the lower basin is the Highland Lakes chain of reservoirs in Central Texas. The use of water from these lakes for environmental protection and enhancement has received increasing attention in recent years. The LCRA recently completed major revisions to its comprehensive Water Management Plan (WMP) for the Highland Lakes. These revisions included changes to incorporate the results of a three year study of instream flow needs in the lower Colorado River. The instream flow needs were determined to consist of two flow regimes: critical and target. The critical flows are considered to be the daily minimum flows needed to maintain minimum viable aquatic conditions for important fish species. The target flow needs are those daily flows which maximize the available habitat for a variety of fish. After evaluating numerous policy options, LCRA revised to WMP to allow the release of water from the Highland Lakes to maintain the daily river flows at no less than the critical flows in all years. Further, in those years when drought-induced irrigation water supply curtailments do not occur, LCRA will release water from the lakes, to the extent of daily inflows, to maintain daily river flows at no less than the target levels. To fully honor this pledge, LCRA committed an average of 28,700 acre-feet annually, during any ten consecutive years, from the dependable supply of the Highland Lakes

  15. Analysis of Environmental Issues Related to Small-Scale Hydroelectric Development V: Instream Flow Needs for Fishery Resources

    Energy Technology Data Exchange (ETDEWEB)

    Loar, James M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sale, Michael J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    1981-10-01

    The purpose of this document is to provide guidance to developers of small-scale hydroelectric projects on the assessment of instream flow needs. While numerous methods have been developed to assess the effects of stream flow regulation on aquatic biota in coldwater streams in the West, no consensus has been reached regarding their general applicability, especially to streams in the eastern United States. This report presents and reviews these methods (Section 2.0), which is intended to provide the reader with general background information that is the basis for the critical evaluation of the methods (Section 3.0). The strategy for instream flow assessment presented in Section 4.0 is, in turn, based on the implicit assumptions, data needs, costs, and decision-making capabilities of the various methods as discussed in Section 3.0.

  16. Testing the effects of in-stream sediment sources and sinks on simulated watershed sediment yield using the coupled U.S. Army Corps of Engineers GSSHA Model and SEDLIB Sediment Transport Library

    Science.gov (United States)

    Floyd, I. E.; Downer, C. W.; Brown, G.; Pradhan, N. R.

    2017-12-01

    The Gridded Surface Subsurface Hydrologic Analysis (GSSHA) model is the US Army Corps of Engineers' (USACE)'s only fully coupled overland/in-stream sediment transport model. While the overland sediment transport formulation in GSSHA is considered state of the art, the existing in-stream sediment transport formulation is less robust. A major omission in the formulation of the existing GSSHA in-stream model is the lack of in-stream sources of fine materials. In this effort, we enhanced the in-stream sediment transport capacity of GSSHA by linking GSSHA to the SEDLIB sediment transport library. SEDLIB was developed at the Coastal and Hydraulics Laboratory (CHL) under the System Wide Water Resources Program (SWWRP) and Flood and Coastal (F&C) research program. It is designed to provide a library of sediment flux formulations for hydraulic and hydrologic models, such as GSSHA. This new version of GSSHA, with the updated in-stream sediment transport simulation capability afforded by the linkage to SEDLIB, was tested in against observations in an experimental watershed that had previously been used as a test bed for GSSHA. The results show a significant improvement in the ability to model in-stream sources of fine sediment. This improved capability will broaden the applicability of GSSHA to larger watersheds and watersheds with complex sediment dynamics, such as those subjected to fire hydrology.

  17. Deciphering relationships between in-stream travel times, nutrient concentrations, and uptake through analysis of hysteretic and non-hysteretic kinetic behavior

    Science.gov (United States)

    Covino, T. P.; Bowden, W. B.; Gooseff, M. N.; Wollheim, W. M.; McGlynn, B. L.; Whittinghill, K. A.; Wlostowski, A. N.; Herstand, M. R.

    2012-12-01

    Understanding the relationship between solute travel time, concentration, and nutrient uptake remains a central question in watershed hydrology and biogeochemistry. Theoretical understanding predicts that nutrient uptake should increase as in-stream solute travel time lengthens and/or as concentration increases; however, results from field-based studies have been contradictory. We used a newly developed approach, Tracer Additions for Spiraling Curve Characterization (TASCC), to investigate relationships between solute travel time, nutrient concentration, and nutrient uptake across a range of stream types. This approach allows us to quantify in-stream nutrient uptake across a range of travel times and nutrient concentrations using single instantaneous injections (slugs) of conservative and non-conservative tracers. In some systems we observed counter-clockwise hysteresis loops in the relationship between nutrient uptake and concentration. Greater nutrient uptake on the falling limb of tracer breakthrough curves indicates stronger uptake for a given concentration at longer travel times. However, in other systems we did not observe hysteresis in these relationships. Lack of hysteresis indicates that nutrient uptake kinetics were not influenced by travel time travel time. Here we investigate the potential roles of travel time and in-stream flowpaths that could be responsible for hysteretic behavior.

  18. Shear Creep Simulation of Structural Plane of Rock Mass Based on Discontinuous Deformation Analysis

    Directory of Open Access Journals (Sweden)

    Guoxin Zhang

    2017-01-01

    Full Text Available Numerical simulations of the creep characteristics of the structural plane of rock mass are very useful. However, most existing simulation methods are based on continuum mechanics and hence are unsuitable in the case of large displacements and deformations. The discontinuous deformation analysis method proposed by Genhua is a discrete one and has a significant advantage when simulating the contacting problem of blocks. In this study, we combined the viscoelastic rheological model of Burgers with the discontinuous deformation analysis (DDA method. We also derived the recurrence formula for the creep deformation increment with the time step during numerical simulations. Based on the minimum potential energy principle, the general equilibrium equation was derived, and the shear creep deformation in the structural plane was considered. A numerical program was also developed and its effectiveness was confirmed based on the curves obtained by the creep test of the structural plane of a rock mass under different stress levels. Finally, the program was used to analyze the mechanism responsible for the creep features of the structural plane in the case of the toppling deformation of the rock slope. The results showed that the extended DDA method is an effective one.

  19. Application of electrical tomography to study the internal structure of rock glaciers in Altai

    OpenAIRE

    G. S. Dyakova; V. V. Olenchenko; O. V. Ostanin

    2017-01-01

    Internal structure of rock glaciers was investigated at two key sites in Altai by means of electric tomography. It had been found that the rock glaciers of the same type, located at different altitude levels, differ in electric resistances of ice nuclei and the degree of consolidation of the ice material inside of them. Typical characteristics of the ice core of a rock glacier in the high-mountain area are the following: electrical resistivity is about 1000–2000 kOhm∙m and a high degree of th...

  20. The USANS technique for the investigation of structure from hydrated gels to porous rock

    International Nuclear Information System (INIS)

    Crompton, Kylie; Forsythe, John; Bertram, Willem; Knott, R.B.; Barker, John

    2005-01-01

    Full text: The Ultra Small Angle Neutron Scattering (USANS) technique extends the range of the Small Angle Neutron Scattering (SANS) technique into the tens of micron size range. This is extremely useful for many systems particularly those where sample preparation for optical or electron microscopy can cause major changes to the microstructure under investigation. Two examples will be presented to highlight different aspects of the technique. Firstly, the structure was investigated of a full hydrated polymer scaffold for stem cells constructed from chitosan. Stem cells interact with the scaffold on the micron scale however information on the nanoscale (i e individual chitosan polymer chains) is also required in order the tailor the scaffold structure. The soft, hydrated gel is unsuitable for optical or electron microscopy. Secondly, the structure was investigated of natural oil-bearing and synthetic rock. The scattering data from different thickness of rock was analysed using a Fourier Transform method to remove multiple scattering effects and to simulate scattering from a thin rock. In this case bulk properties such as porosity are of interest. (authors)

  1. Some new developments in the design rules for coastal structures in relation with the new Rock Manual

    NARCIS (Netherlands)

    Verhagen, H.J.

    2005-01-01

    In 1991 CUR in the Netherlands and CIRIA in the UK have published the "manual on the use of rock in coastal engineering", usually referred to as the "Rock Manual". This book of 600 pages gave an overview of the state of the art regarding the design of rock structures along coasts. In 1995 CUR

  2. Application of electrical tomography to study the internal structure of rock glaciers in Altai

    Directory of Open Access Journals (Sweden)

    G. S. Dyakova

    2017-01-01

    Full Text Available Internal structure of rock glaciers was investigated at two key sites in Altai by means of electric tomography. It had been found that the rock glaciers of the same type, located at different altitude levels, differ in electric resistances of ice nuclei and the degree of consolidation of the ice material inside of them. Typical characteristics of the ice core of a rock glacier in the high-mountain area are the following: electrical resistivity is about 1000–2000 kOhm∙m and a high degree of the ice consolidation, while the same for the mid-mountain region: the electrical resistivity is 150–300 kOhm∙m and the presence of the talik zones within the glacier body. Using the method of electric tomography for investigation of the internal structure of the rock-glaciers makes possible to reveal presence of frozen soils and ice and to find the upper boundary of occurrence of them from anomalously high specific electric resistance. However, it is not always possible to determine a thickness of the rock-ice formation, and to estimate a degree of its consolidation that does not allow calculating the ice content volume. Limitations of this technology can be overcome by the use of electric tomography in combination with other geophysical methods.

  3. Quantifying in-stream nitrate reaction rates using continuously-collected water quality data

    Science.gov (United States)

    Matthew Miller; Anthony Tesoriero; Paul Capel

    2016-01-01

    High frequency in situ nitrate data from three streams of varying hydrologic condition, land use, and watershed size were used to quantify the mass loading of nitrate to streams from two sources – groundwater discharge and event flow – at a daily time step for one year. These estimated loadings were used to quantify temporally-variable in-stream nitrate processing ...

  4. Nova Scotia Power : in-stream tidal

    International Nuclear Information System (INIS)

    Meade, K.

    2007-01-01

    The Government of Nova Scotia, the Government of New Brunswick, Nova Scotia Power and others have funded a feasibility study of North American sites for commercial instream tidal power. In July 2007, Nova Scotia Power received partial funding for a demonstration project. This presentation provided information on a demonstration plant for tidal power run by Nova Scotia Power. It discussed the benefits of the Open Hydro technology for this plant. In this simple design, the generator is on the circumference of the turbine. The design does not involve any power transmission systems or any pitching of blades. In addition, the technology is environmentally sound as it is completely shrouded, has low rotational speed, and a large open centre allows fish to pass through, and it does not require lubricants. The last benefit that was presented was the scale up of 250 kW machine deployed in a European test facility. The presentation also discussed the advantages of developing tidal power at this time. It was concluded that tidal energy has significant potential. Although it is intermittent, it is predictable and bulk power system can be scheduled to accommodate it. figs

  5. Seismic performance evaluation of an infilled rocking wall frame structure through quasi-static cyclic testing

    Science.gov (United States)

    Pan, Peng; Wu, Shoujun; Wang, Haishen; Nie, Xin

    2018-04-01

    Earthquake investigations have illustrated that even code-compliant reinforced concrete frames may suffer from soft-story mechanism. This damage mode results in poor ductility and limited energy dissipation. Continuous components offer alternatives that may avoid such failures. A novel infilled rocking wall frame system is proposed that takes advantage of continuous component and rocking characteristics. Previous studies have investigated similar systems that combine a reinforced concrete frame and a wall with rocking behavior used. However, a large-scale experimental study of a reinforced concrete frame combined with a rocking wall has not been reported. In this study, a seismic performance evaluation of the newly proposed infilled rocking wall frame structure was conducted through quasi-static cyclic testing. Critical joints were designed and verified. Numerical models were established and calibrated to estimate frame shear forces. The results evaluation demonstrate that an infilled rocking wall frame can effectively avoid soft-story mechanisms. Capacity and initial stiffness are greatly improved and self-centering behavior is achieved with the help of the infilled rocking wall. Drift distribution becomes more uniform with height. Concrete cracks and damage occurs in desired areas. The infilled rocking wall frame offers a promising approach to achieving seismic resilience.

  6. Large wood and in-stream habitat for juvenile coho salmon and larval lampreys in a Pacific Northwest stream

    Science.gov (United States)

    Gonzalez, Rosalinda; Dunham, Jason B.; Lightcap, Scott W.; McEnroe, Jeffery R.

    2017-01-01

    The influences of large wood on Pacific salmon are well-studied, but studies of nonsalmonid species such as lampreys are uncommon. To address this need, we evaluated the potential effects of large wood on larval lampreys (Pacific Lamprey, Entosphenus tridentatus; and potentially Western Brook Lamprey Lampetra richardsoni), as well as juvenile Coho Salmon Oncorhynchus kisutch, in a small coastal Oregon stream. Our objectives were to 1) identify in-stream habitat characteristics associated with the presence of larval lampreys and abundance of juvenile Coho Salmon; and 2) evaluate how these characteristics were associated with in-stream wood. To address habitat use, we quantified presence of larval lampreys in 92 pools and abundance of juvenile Coho Salmon in 44 pools during summer low flows. We focused on a study reach where large wood was introduced into the stream between 2008 and 2009. Results indicated that presence of larval lampreys was significantly associated with availability of fine sediment and deeper substrate. The abundance of juvenile Coho Salmon (fish/pool) was strongly associated with pool surface area and to a weaker extent with the proportion of cobble and boulder substrates in pools. Pools with wood, regardless of whether they were formed by wood, had significantly greater coverage of fine sediment, deeper substrate, and greater pool surface area. Taken together, these results suggest that in-stream wood can provide habitat associated with presence of larval lampreys and greater abundance of juvenile Coho Salmon.

  7. Soil-structure interaction effects in seismic analysis of turbine generator building on rock-like foundation

    International Nuclear Information System (INIS)

    Park, Chi Seon; Lee, Sang Hoon; Yoo, Kwang Hoon

    2004-01-01

    Soil properties supporting structure may become criteria determining methodologies for seismic response analysis of a structure. Regulatory Guide describes that a fixed-base assumption is acceptable for structures supported on rock or rock-like materials defined by a shear wave velocity of 3,500 ft/sec or greater at a shear strain of 10 -3 percent or smaller when considering preloaded soil conditions due to the structure. Seismic analyses for the Korean nuclear power plant (NPP) structures satisfying the above site soil condition have been completed through the fixed-base analysis. However, dynamic responses for relatively stiff structures such as NPP structures still have soil-structure interaction (SSI) effects. In other words, the fixed-base analysis does not always yield conservative results to be compared with SSI analysis. The SSI effects due to different stiff soil properties for Turbine Generator Building (TGB) structure to be constructed at Kori site of South Korea are investigated in views of floor response spectra (FRS) and member forces

  8. Use of structural geology in exploration for and mining of sedimentary rock-hosted Au deposits

    Science.gov (United States)

    Peters, Stephen G.

    2001-01-01

    Structural geology is an important component in regional-, district- and orebody-scale exploration and development of sedimentary rock-hosted Au deposits.Identification of timing of important structural events in an ore district allows analysis and classification of fluid conduits and construction of genetic models for ore formation.The most practical uses of structural geology deal with measurement and definition of various elements that comprise orebodies, which can then be directly applied to ore-reserve estimation,ground control,grade control, safety issues,and mine planning.District- and regional-scale structural studies are directly applicable to long-term strategic planning,economic analysis,and land ownership. Orebodies in sedimentary rock-hosted Au deposits are discrete, hypogene, epigenetic masses usually hosted in a fault zone,breccia mass, or lithologic bed or unit. These attributes allow structural geology to be directly applied to the mining and exploration of sedimentary rock-hosted Au deposits. Internal constituents in orebodies reflect unique episodes relating to ore formation.The main internal constituents in orebodies are ore minerals, gangue, and alteration minerals that usually are mixed with one another in complex patterns, the relations among which may be used to interpret the processes of orebody formation and control.Controls of orebody location and shape usually are due to structural dilatant zones caused by changes in attitude, splays, lithologic contacts,and intersections of the host conduit or unit.In addition,conceptual parameters such as district fabric,predictable distances, and stacking also are used to understand the geometry of orebodies.Controls in ore districts and location and geometry of orebodies in ore districts can be predicted to various degrees by using a number of qualitative concepts such as internal and external orebody plunges,district plunge, district stacking, conduit classification, geochemical, geobarometric and

  9. Technogenic Rock Dumps Physical Properties' Prognosis via Results of the Structure Numerical Modeling

    Directory of Open Access Journals (Sweden)

    Markov Sergey

    2017-01-01

    Full Text Available Understanding of internal structure of the technogenic rock dumps (gob dumps is required condition for estimation of using ones as filtration massifs for treatment of mine wastewater. Internal structure of gob piles greatly depends on dumping technology to applying restrictions for use them as filtration massifs. Numerical modelling of gob dumps allows adequately estimate them physical parameters, as a filtration coefficient, density, etc. The gob dumps numerical modelling results given in this article, in particular was examined grain size distribution of determined fractions depend on dump height. Shown, that filtration coefficient is in a nonlinear dependence on amount of several fractions of rock in gob dump. The numerical model adequacy both the gob structure and the dependence of filtration coefficient from gob height acknowledged equality of calculated and real filtration coefficient values. The results of this research can be apply to peripheral dumping technology.

  10. Instream Flows Incremental Methodology :Kootenai River, Montana : Final Report 1990-2000.

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, Greg; Skaar, Don; Dalbey, Steve (Montana Department of Fish, Wildlife and Parks, Libby, MT)

    2002-11-01

    Regulated rivers such as the Kootenai River below Libby Dam often exhibit hydrographs and water fluctuation levels that are atypical when compared to non-regulated rivers. These flow regimes are often different conditions than those which native fish species evolved with, and can be important limiting factors in some systems. Fluctuating discharge levels can change the quantity and quality of aquatic habitat for fish. The instream flow incremental methodology (IFIM) is a tool that can help water managers evaluate different discharges in terms of their effects on available habitat for a particular fish species. The U.S. Fish and Wildlife Service developed the IFIM (Bovee 1982) to quantify changes in aquatic habitat with changes in instream flow (Waite and Barnhart 1992; Baldridge and Amos 1981; Gore and Judy 1981; Irvine et al. 1987). IFIM modeling uses hydraulic computer models to relate changes in discharge to changes in the physical parameters such as water depth, current velocity and substrate particle size, within the aquatic environment. Habitat utilization curves are developed to describe the physical habitat most needed, preferred or tolerated for a selected species at various life stages (Bovee and Cochnauer 1977; Raleigh et al. 1984). Through the use of physical habitat simulation computer models, hydraulic and physical variables are simulated for differing flows, and the amount of usable habitat is predicted for the selected species and life stages. The Kootenai River IFIM project was first initiated in 1990, with the collection of habitat utilization and physical hydraulic data through 1996. The physical habitat simulation computer modeling was completed from 1996 through 2000 with the assistance from Thomas Payne and Associates. This report summarizes the results of these efforts.

  11. Rock mechanics investigations of structural stability in the Bulli seam at West Cliff Colliery

    Energy Technology Data Exchange (ETDEWEB)

    Jaggar, F

    1978-03-01

    Rock mechanics investigations were conducted at West Cliff colliery to obtain rock properties and stress measurements and study the stability of mining structures. The roof and floor were drilled in order to obtain core for rock testing and lump samples of coal were collected in order to measure the coal properties. Absolute stress measurements were obtained using CSIR cells. The strata were sufficiently uniform and competent to overcore the emplaced cells. Testing revealed that the rocks were better than average for coal measure sedimentary strata and the stresses indicated the existence of a moderately high horizontal stress field. The coal is of average strength only with some marked variation relating to the very banded nature of the seam. Finite element analyses showed that the rectangular roadways driven using roof bolts and timber supports were stable and adequately stable by an indicative factor of safety of about l.5.

  12. Assessing changes to in-stream turbidity following construction of a forest road in West Virginia

    Science.gov (United States)

    Jingxin Wang; Pamela J. Edwards; William A. Goff

    2011-01-01

    Two forested headwater watersheds were monitored to examine changes to in-stream turbidity following the construction of a forest haul road. One watershed was used as an undisturbed reference, while the other had a 0.92-km (0.57-mi) haul road constructed in it. The channels in both are intermittent tributaries of the Left Fork of Clover Run in the Cheat River watershed...

  13. Rock foundations of hydroengineering structures: mechanical properties and calculations. Skal'nye osnovaniya gidrotekhnicheskikh sooruzhenii: mekhanicheskie svoistva i raschety

    Energy Technology Data Exchange (ETDEWEB)

    Ukhov, S B

    1975-01-01

    This book presents the analytical methods which are used to describe the processes of the deformation and collapse of the rock-dirt foundations of dams, and techniques are presented for experimentally determining the mechanical properties of fissured rock-dirt under natural conditions. A determination is made of the required complex of engineering-geological, geophysical and geomechanical methods of investigation for calculating the interaction of the structure and the foundation, and a report is also given on the main assumptions of such calculations by using the method of finite elements. Methods are recommended for estimating the effect of engineering actions on the change in mechanical properties of the rock-dirt foundation. The book is intended for engineering dealing with the search and design of dam structures constructed on rock foundations. 126 refs.

  14. Acoustic remote monitoring of rock and concrete structures for nuclear waste repositories

    International Nuclear Information System (INIS)

    Young, R.P.

    2000-01-01

    Excavation and thermally induced damage is of significance for many types of engineering structures but no more so than in the case of nuclear waste repository design. My research and that of my group, formally at Queen's University Canada and Keele University UK and now at the University of Liverpool UK, has focused on the development of acoustic techniques for the in situ detection and quantification of induced damage and fracturing. The application of earthquake seismology to this problem has provided the opportunity to study the micro mechanics of damage mechanisms in situ and provide validation data for predictive geomechanical models used for engineering design. Since 1987 I have been a principal investigator at Atomic Energy of Canada's Underground Research Laboratory (URL), responsible for the development of acoustic emission techniques (AE). In the last twelve years, the application of acoustic techniques to rock damage assessment has been pioneered by my group at the URL and successfully applied in several other major international projects including the ZEDEX, Retrieval and Prototype repository experiments at the Aspo Hard Rock Laboratory (HRL) of SKB Sweden. In this paper I describe what information is available by remote acoustic monitoring of rock and concrete structures and demonstrate this with reference to two international scientific experiments carried out at the URL Canada and the HRL Sweden. (author)

  15. The Usability of Rock-Like Materials for Numerical Studies on Rocks

    Science.gov (United States)

    Zengin, Enes; Abiddin Erguler, Zeynal

    2017-04-01

    The approaches of synthetic rock material and mass are widely used by many researchers for understanding the failure behavior of different rocks. In order to model the failure behavior of rock material, researchers take advantageous of different techniques and software. But, the majority of all these instruments are based on distinct element method (DEM). For modeling the failure behavior of rocks, and so to create a fundamental synthetic rock material model, it is required to perform related laboratory experiments for providing strength parameters. In modelling studies, model calibration processes are performed by using parameters of intact rocks such as porosity, grain size, modulus of elasticity and Poisson ratio. In some cases, it can be difficult or even impossible to acquire representative rock samples for laboratory experiments from heavily jointed rock masses and vuggy rocks. Considering this limitation, in this study, it was aimed to investigate the applicability of rock-like material (e.g. concrete) to understand and model the failure behavior of rock materials having complex inherent structures. For this purpose, concrete samples having a mixture of %65 cement dust and %35 water were utilized. Accordingly, intact concrete samples representing rocks were prepared in laboratory conditions and their physical properties such as porosity, pore size and density etc. were determined. In addition, to acquire the mechanical parameters of concrete samples, uniaxial compressive strength (UCS) tests were also performed by simultaneously measuring strain during testing. The measured physical and mechanical properties of these extracted concrete samples were used to create synthetic material and then uniaxial compressive tests were modeled and performed by using two dimensional discontinuum program known as Particle Flow Code (PFC2D). After modeling studies in PFC2D, approximately similar failure mechanism and testing results were achieved from both experimental and

  16. Discussion on the origin of sedimentary rock resistivity

    International Nuclear Information System (INIS)

    Dong Gangjian

    2012-01-01

    Conduction current way of sedimentary rock sedimentary rock is caused by the internal structure of sedimentary rock sedimentary rock pore resistance depends on the salinity of pore water and clay content and distribution. Resistivity of sedimentary rock sedimentary rock major factor in mineral composition, water resistance, oil resistance. and sedimentary structures. In practice, we should give full attention to the difference between lithology and physical properties. (author)

  17. Modeling nutrient in-stream processes at the watershed scale using Nutrient Spiralling metrics

    Science.gov (United States)

    Marcé, R.; Armengol, J.

    2009-07-01

    One of the fundamental problems of using large-scale biogeochemical models is the uncertainty involved in aggregating the components of fine-scale deterministic models in watershed applications, and in extrapolating the results of field-scale measurements to larger spatial scales. Although spatial or temporal lumping may reduce the problem, information obtained during fine-scale research may not apply to lumped categories. Thus, the use of knowledge gained through fine-scale studies to predict coarse-scale phenomena is not straightforward. In this study, we used the nutrient uptake metrics defined in the Nutrient Spiralling concept to formulate the equations governing total phosphorus in-stream fate in a deterministic, watershed-scale biogeochemical model. Once the model was calibrated, fitted phosphorus retention metrics where put in context of global patterns of phosphorus retention variability. For this purpose, we calculated power regressions between phosphorus retention metrics, streamflow, and phosphorus concentration in water using published data from 66 streams worldwide, including both pristine and nutrient enriched streams. Performance of the calibrated model confirmed that the Nutrient Spiralling formulation is a convenient simplification of the biogeochemical transformations involved in total phosphorus in-stream fate. Thus, this approach may be helpful even for customary deterministic applications working at short time steps. The calibrated phosphorus retention metrics were comparable to field estimates from the study watershed, and showed high coherence with global patterns of retention metrics from streams of the world. In this sense, the fitted phosphorus retention metrics were similar to field values measured in other nutrient enriched streams. Analysis of the bibliographical data supports the view that nutrient enriched streams have lower phosphorus retention efficiency than pristine streams, and that this efficiency loss is maintained in a wide

  18. Instream biological assessment of NPDES point source discharges at the Savannah River Site, 1997-1998

    International Nuclear Information System (INIS)

    Specht, W.L.

    2000-01-01

    The Savannah River Site currently has 33 permitted NPDES outfalls that have been permitted by the South Carolina Department of Health an Environmental Control to discharge to SRS streams and the Savannah River. In order to determine the cumulative impacts of these discharges to the receiving streams, a study plan was developed to perform in-stream assessments of the fish assemblages, macroinvertebrate assemblages, and habitats of the receiving streams

  19. Instream biological assessment of NPDES point source discharges at the Savannah River Site, 1997-1998

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L.

    2000-02-28

    The Savannah River Site currently has 33 permitted NPDES outfalls that have been permitted by the South Carolina Department of Health an Environmental Control to discharge to SRS streams and the Savannah River. In order to determine the cumulative impacts of these discharges to the receiving streams, a study plan was developed to perform in-stream assessments of the fish assemblages, macroinvertebrate assemblages, and habitats of the receiving streams.

  20. Lattice stability of metastable AlN and wurtzite-to-rock-salt structural transformation by CALPHAD modeling

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yanhui, E-mail: yanhui.z@hotmail.com [Karlsruhe Institute of Technology (KIT), Institute for Applied Materials-Applied Materials Physics (IAM-AWP), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); High-performance Ceramics Division, Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016, Shenyang (China); Franke, Peter; Li, Dajian; Seifert, Hans Jürgen [Karlsruhe Institute of Technology (KIT), Institute for Applied Materials-Applied Materials Physics (IAM-AWP), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2016-12-01

    Reliable lattice stability of cubic AlN with rock-salt structure (rs-AlN) is the prerequisite of accurate thermodynamic modeling of cubic (M, Al)N solid solutions (M = Ti, Zr, Cr etc.). In order to derive the Gibbs energy of metastable rs-AlN, and then its lattice stability, we did the pressure-temperature (P-T) assessment of AlN phases by equations-of-state modeling. Meanwhile, the molar volumes and the heat capacities of wurtzite and rock-salt AlN, as well as the wurtzite-to-rock-salt structural transition at high P&T were successfully incorporated in CALPHAD-type database by integrating thermodynamic data from experiments and ab-initio calculations. These results promise subsequent investigations on phase stabilities and transitions of solid solutions with AlN component and the development of novel multicomponent coatings. - Highlights: • Phase stability investigation for novel multi-component metastable coatings. • Structural transition at high temperature and high pressure. • Integrating thermodynamic data from ab-initio calculations and experiments. • Thermal expansion, isothermal compressibility and heat capacity of w-AlN and rs-AlN.

  1. Well log and seismic data analysis for complex pore-structure carbonate reservoir using 3D rock physics templates

    Science.gov (United States)

    Li, Hongbing; Zhang, Jiajia

    2018-04-01

    The pore structure in heterogeneous carbonate rock is usually very complex. This complex pore system makes the relationship between the velocity and porosity of the rock highly scattered, so that for the classical two-dimensional rock physics template (2D RPT) it is not enough to accurately describe the quantitative relationship between the rock elastic parameters of this kind of reservoir and its porosity and water saturation. Therefore it is possible to attribute the effect of pore type to that of the porosity or water saturation, and leads to great deviations when applying such a 2D RPT to predict the porosity and water saturation in seismic reservoir prediction and hydrocarbon detection. This paper first presents a method to establish a new three-dimensional rock physics template (3D RPT) by integrating the Gassmann equations and the porous rock physics model, and use it to characterize the quantitative relation between rock elastic properties and the reservoir parameters including the pore aspect ratio, porosity and water saturation, and to predict these parameters from the known elastic properties. The test results on the real logging and seismic inversion data show that the 3D RPT can accurately describe the variations of elastic properties with the porosity, water saturation and pore-structure parameters, and effectively improve the accuracy of reservoir parameters prediction.

  2. Evidence for a Meteoritic Component in Impact Melt Rock from the Chicxulub Structure

    Science.gov (United States)

    Koeberl, Christian; Sharpton, Virgil L.; Schuraytz, Benjamin C.; Shirey, Steven B.; Blum, Joel D.; Marin, Luis E.

    1994-01-01

    The Chicxulub structure in Yucatan, Mexico, has recently been recognized as a greater then 200-km-diameter multi-ring impact crater of K-T boundary age. Crystalline impact melt rocks and breccias from within the crater, which have compositions similar to those of normal continental crustal rocks and which show shock metamorphic effects, have been studied for trace element and Re-Os isotope compositions. Re-Os isotope systematics allow the sensitive and selective determination of an extraterrestrial component in impact-derived rocks. A melt rock sample shows elevated iridium concentrations, an osmium concentration of 25 ppb, and a low Os-187/Os-188 ratio of 0.113, which are incompatible with derivation from the continental crust. Even though the Os-187/Os-188 ratio is slightly lower than the range so far measured in meteorites, a mantle origin seems unlikely for mass balance reasons and because the cratering event is unlikely to have excavated mantle material. The data support the hypothesis of a heterogeneously distributed meteoritic component in the Chicxulub melt rock. A sample of impact glass from the Haitian K-T boundary at Beloc yielded about 0.1 ppb osmium and an Os-187/0s-188 ratio of 0.251, indicating the presence of a small meteoritic component in the impact ejecta as well.

  3. Application of a water quality model for determining instream aeration station location and operational rules: A case study

    Directory of Open Access Journals (Sweden)

    Charles S. Melching

    2018-01-01

    Full Text Available Instream aeration has been used as a supplement to secondary treatment or a substitute for tertiary treatment for meeting dissolved oxygen (DO standards in rivers. Many studies have used water quality models to determine the number, location, and capacity of instream aeration stations (IASs needed to meet DO standards in combination with other pollution control measures. DO concentrations have been improved in the North Shore Channel and North Branch Chicago River by the Devon Avenue IAS for more than 35 years. A study was initiated to determine whether it was better to rehabilitate or relocate this station and to determine appropriate operational guidance for the IAS at the selected location. A water quality model capable of simulating DO concentrations during unsteady flow was used to evaluate the proper location for an IAS and operational guidance for this IAS. Three test years, a dry year, a wet year, and an extreme year, were considered in the evaluation. The study found that the Devon Avenue IAS should be rehabilitated as this location performed as well as or better than any of 10 alternative locations. According to the new operational guidance for this IAS, the amount of time with blowers operating could be substantially reduced compared to traditional operations while at the same time the attainment of the DO standards could be increased. This study shows that a carefully designed modeling study is key to effective selection, location, and operation of IASs such that attainment of DO standards can be maximized while operation hours of blowers can be minimized. Keywords: Instream aeration, Dissolved oxygen, Water quality modeling, Water quality management, Computer simulation

  4. Technical Note: A comparison of two empirical approaches to estimate in-stream net nutrient uptake

    Science.gov (United States)

    von Schiller, D.; Bernal, S.; Martí, E.

    2011-04-01

    To establish the relevance of in-stream processes on nutrient export at catchment scale it is important to accurately estimate whole-reach net nutrient uptake rates that consider both uptake and release processes. Two empirical approaches have been used in the literature to estimate these rates: (a) the mass balance approach, which considers changes in ambient nutrient loads corrected by groundwater inputs between two stream locations separated by a certain distance, and (b) the spiralling approach, which is based on the patterns of longitudinal variation in ambient nutrient concentrations along a reach following the nutrient spiralling concept. In this study, we compared the estimates of in-stream net nutrient uptake rates of nitrate (NO3) and ammonium (NH4) and the associated uncertainty obtained with these two approaches at different ambient conditions using a data set of monthly samplings in two contrasting stream reaches during two hydrological years. Overall, the rates calculated with the mass balance approach tended to be higher than those calculated with the spiralling approach only at high ambient nitrogen (N) concentrations. Uncertainty associated with these estimates also differed between both approaches, especially for NH4 due to the general lack of significant longitudinal patterns in concentration. The advantages and disadvantages of each of the approaches are discussed.

  5. A first-principles study of half-metallic ferromagnetism in binary alkaline-earth nitrides with rock-salt structure

    International Nuclear Information System (INIS)

    Gao, G.Y.; Yao, K.L.; Liu, Z.L.; Zhang, J.; Min, Y.; Fan, S.W.

    2008-01-01

    In this Letter, using the first-principles full-potential linearized augmented plane-wave (FP-LAPW) method, we extend the electronic structure and magnetism studies on zinc-blende structure of II-V compounds MX (M=Ca,Sr,Ba; X=N,P,As) [M. Sieberer, J. Redinger, S. Khmelevskyi, P. Mohn, Phys. Rev. B 73 (2006) 024404] to the rock-salt structure. It is found that, in the nine compounds, only alkaline-earth nitrides CaN, SrN and BaN exhibit ferromagnetic half-metallic character with a magnetic moment of 1.00μ B per formula unit. Furthermore, compared with the zinc-blende structure of CaN, SrN and BaN, the rock-salt structure has lower energy, which makes them more promising candidates of possible growth of half-metallic films on suitable substrates

  6. Influence of various excavation techniques on the structure and physical properties of 'near-field' rock around large boreholes

    International Nuclear Information System (INIS)

    Pusch, R.

    1989-12-01

    The procedure employed in the excavation of canister deposition holes affects the structure and physical properties of the 'near-field' rock. Except for smooth blasting, the generated damage appears to be less important than the increase in 'axial' hydraulic conductivity that is caused by stress release effects, but both combine to yield significant local flow passages. This is particularly obvious where the rock structure yield steep wedges, which is frequently occurring in granite. Percussion drilling is concluded to cause rich fine-fissuring to a distance of up to one centimeter from the borehole wall, and 'discing'. Richer fissuring and some generation of new fractures and growth of preexisting ones are produced within several decimeters from the borehole wall by full-face drilling. Core drilling has the least effect on the rock structure. Smooth blasting produces a particular form of regular fractures which appear to be determinants of the hydraulic conductivity of the near-field rock. Theoretically, its conductivity in the axial direction of blasted big holes or tunnels should be in the range of 10 -8 - 10 -6 m/s, which is in agreement with measurements in the Stripa mine. (orig.)

  7. Stratigraphy and structure of volcanic rocks in drill hole USW-G1, Yucca Mountain, Nye County, Nevada

    International Nuclear Information System (INIS)

    Spengler, R.W.; Byers, F.M. Jr.; Warner, J.B.

    1981-01-01

    Detailed subsurface studies in connection with the Nevada Nuclear Waste Storage Investigations program are being conducted to investigate the stratigraphic and structural features of volcanic rocks underlying Yucca Mountain, a volcanic highland situated along the western boundary of the Nevada Test Site in southern Nevada. As part of this continuing effort, drill hole USW-G1 was cored from 292 ft to a depth of 6000 ft from March to August 1980. The stratigraphic section is composed of thick sequences of ash-flow tuff and volcanic breccia interbedded with subordinate amounts of fine- to coarse-grained volcaniclastic rocks. All rocks are of Tertiary age and vary in composition from rhyolite to dacite. The 3005-ft level in the drill hole represents a significant demarcation between unaltered and altered volcanic rocks. For the most part, tuff units above 3005 ft appear devitrified and show little secondary alteration except within tuffaceous beds of Calico Hills, where the rock contains 60 to 80% zeolites. Below 3005 ft, most rocks show intermittent to pervasive alteration to clay minerals and zeolites. Examination of core for structural features revealed the presence of 61 shear fractures, 528 joints, and 4 conspicuous fault zones. Shear fractures mainly occurred in the Topopah Spring Member of the Paintbrush Tuff, flow breccia, and near fault zones. Nearly 88% of shear and joint surfaces show evidence of coatings. Approximately 40% of the fractures were categorized as completely healed. Rock quality characteristics as defined by the core index indicate that greater amounts of broken and lost core are commonly associated with (1) the densely welded zone of the Topopah Spring, (2) highly silicified zones, and (3) fault zones

  8. Development of a rocking R/C shear wall system implementing repairable structural fuses

    Science.gov (United States)

    Parsafar, Saeed; Moghadam, Abdolreza S.

    2017-09-01

    In the last decades, the concept of earthquake resilient structural systems is becoming popular in which the rocking structure is considered as a viable option for buildings in regions of high seismicity. To this end, a novel wall-base connection based on the " repairable structure" approach is proposed and evaluated. The proposed system is made of several steel plates and high strength bolts act as a friction connection. To achieve the desired rocking motion in the proposed system, short-slotted holes are used in vertical directions for connecting the steel plates to the shear wall (SW). The experimental and numerical studies were performed using a series of displacement control quasi-static cyclic tests on a reference model and four different configurations of the proposed connection installed at the wall corners. The seismic response of the proposed system is compared to the conventional SW in terms of energy dissipation and damage accumulation. In terms of energy dissipation, the proposed system depicted better performance with 95% more energy dissipation capability compared to conventional SW. In terms of damage accumulation, the proposed SW system is nearly undamaged compared to the conventional wall system, which was severely damaged at the wall-base region. Overall, the introduced concept presents a feasible solution for R/C structures when a low-damage design is targeted, which can improve the seismic performance of the structural system significantly.

  9. Instream cover and shade mediate avian predation on trout in semi-natural streams

    Science.gov (United States)

    Penaluna, Brooke E.; Dunham, Jason B.; Noakes, David L. G.

    2015-01-01

    Piscivory by birds can be significant, particularly on fish in small streams and during seasonal low flow when available cover from predators can be limited. Yet, how varying amounts of cover may change the extent of predation mortality from avian predators on fish is not clear. We evaluated size-selective survival of coastal cutthroat trout (Oncorhynchus clarkii clarkii) in replicated semi-natural stream sections. These sections provided high (0.01 m2 of cover per m2 of stream) or low (0.002 m2 of cover per m2 of stream) levels of instream cover available to trout and were closed to emigration. Each fish was individually tagged, allowing us to track retention of individuals during the course of the 36-day experiment, which we attributed to survival from predators, because fish had no other way to leave the streams. Although other avian predators may have been active in our system and not detected, the only predator observed was the belted kingfisher Megaceryle alcyon, which is known to prey heavily on fish. In both treatments, trout >20.4 cm were not preyed upon indicating an increased ability to prey upon on smaller individuals. Increased availability of cover improved survival of trout by 12% in high relative to low cover stream sections. Trout also survived better in stream sections with greater shade, a factor we could not control in our system. Collectively, these findings indicate that instream cover and shade from avian predators can play an important role in driving survival of fish in small streams or during periods of low flow.

  10. Reverse polarity magnetized melt rocks from the Chicxulub impact structure, Yucatan Peninsula, Mexico

    Science.gov (United States)

    Urrutia-Fucugauchi, Jaime; Marin, Luis E.; Sharpton, Virgil L.; Quezada, Juan Manuel

    1993-03-01

    Further paleomagnetic data for core samples of melt rock recovered in the Petroleos Mexicanos (PEMEX) exploratory wells within the Chicxulub structure, northern Yucatan peninsula, Mexico are reported. A previous report by Sharpton showed that the rocks studied contain high iridium levels and shocked breccia clasts, and an Ar-40/Ar-39 age of 65.2 plus or minus 0.4 Ma. The geomagnetic polarity determined for two samples is reverse (R) and was correlated with chron 29R that includes the K/T boundary. Our present analysis is based on two samples from each of three clasts of the melt rock from PEMEX well Y6-N17 (1295 to 1299 m b.s.l.). This study concentrates on the vectorial nature and stability of the remanence (NRM), the magnetic mineralogy and remanence carriers (i.e., the reliability and origin of the record), and on the implications (correlation with expected paleolatitude and polarity). The relative orientation of the drill core samples with respect to the horizontal is known. Samples were stable under alternating field (AF) and thermal treatments, and after removal of a small component they exhibited single-vectorial behavior. The characteristic remanence inclinations show small dispersion and a mean value (-43 deg) in close agreement with the expected inclination and paleolatitude (derived from the North American apparent polar wander path). Isothermal remenence (IRM) acquisition experiments, Lowrie-Fuller tests, coercivity and unblocking temperature spectra of NRM and saturation IRM, susceptibility and Q-coefficient analyses, and the single-component nature indicate a dominant mineralogy of iron-rich titanomagnetites with single or pseduo-single domain states. The stable characteristic magnetization may be interpreted as a result of shock heating of the rock at the time of formation of the inpact structure and its polarity, age, and paleolatitude are consistent with a time about the K/T boundary.

  11. Variability in Rock Thermal Properties in the Late Archean Crust of the Kapuskasing Structural Zone and Implications for its Thermal Structure and Metamorphic History.

    Science.gov (United States)

    Merriman, J. D.; Whittington, A. G.; Hofmeister, A. M.

    2017-12-01

    The thermal properties of rocks such as internal heat production and thermal diffusivity (α) play a key role in determining the thermal structure of the lithosphere, and consequently, the rates and styles of metamorphism within the crust. Over the last decade, measurements of α using the method laser flash analysis have shown the ability of a rock to conduct heat can vary by as much as a factor of 5 between common rock types, and decrease by up to a factor of 10 for the same rock between 25-1000°C. Here we present a preliminary model for the variability in rock throughout the crust based on measurements of the α of a suite of 100 samples from late Archean crust exposed in and around the Kapuskasing Structural Zone in Ontario, Canada. Preliminary results suggest that α is controlled primarily by mineralogy, and can vary not only between different rock types as described above, but also within the same rock by a factor of 1.5 (or more). Thermal diffusivity results were combined with heat producing element concentrations measured with ICP-MS to create a thermal model of the Kapuskasing Structural Zone prior its uplift and exposure. To provide additional constraints for P-T conditions within the pre-uplift KSZ crust, a combination of trace-element and pseudosection thermobarometry was used to estimate metamorphic temperatures during an extended period of crustal stability at the end of the Archean. Preliminary results were compared to finite-difference numerical models of the steady-state geothermal gradient using heat production back-calculated to 2.6 Ga. Results suggest a minimum thickness of the continental lithosphere during the late Archean of at least 150 km. To test the response of the crust to the effects of large thermal events such as pluton emplacement, we also performed time-dependent models of the thermal structure of the pre-uplift KSZ crust. These models suggest that heat from thermal events in the upper and middle crust result in a more insulating

  12. Migmatites and migmatite-like rocks of Olkiluoto

    International Nuclear Information System (INIS)

    Kaerki, A.

    2015-02-01

    Bedrock of the Olkiluoto Island in the western end of the Palaeoproterozoic Svecofennian Accretionary Arc Complex, SW Finland is composed of high-grade metamorphic pelites, arenites and intermediate, arc type metavolcanic rocks intruded by granodioritic to tonalitic plutonic rocks. Regional metamorphism culminated with voluminous migmatization in the temperature of 660 - 700 deg C and relatively low pressure of about 3.5 - 4 kbar. The end result of polyphase metamorphism and deformation is a metamorphic rock succession composed of diverse migmatite rocks, metatexites and diatexites. Metatexites are migmatites in which several, discrete components can be detected, and in which the paleosome with some pre-partial-melting textures is identifiable. Diatexites are more advanced migmatites in which the pre-migmatization structures are often totally destroyed and the rock is dominated by different neosome components meaning leucosome, melanosome or mesosome. Based on the migmatite structures the metatexites of Olkiluoto have been classified into six subgroups. Dike-structured metatexites are composed of well preserved paleosome intruded by one single set of narrow, subparallel leucosome dikes which cover ca. 5 - 10 % of the whole rock volume. Net-structure is composed of a network of narrow leucosome dikes which show a reticulated structure in a plane section and cover less than 30 % of the whole rock volume. Breccia-structure is composed of angular or rounded paleosome blocks surrounded by moderate amount of leucosome. Patch-structure is composed of irregular leucosome patches which intruded the well preserved paleosome and compose typically 20 - 70 % of the rock volume. Layer-structure is characterized by more or less regular leucosome dikes sub-parallel to the foliation of the well preserved paleosome. Vein-structured metatexites and also diatexites include a set of pipe-like, longish leucosome veins most probably generated by synchronous melting and deformation

  13. Migmatites and migmatite-like rocks of Olkiluoto

    Energy Technology Data Exchange (ETDEWEB)

    Kaerki, A. [Kivitieto Oy, Oulu (Finland)

    2015-02-15

    Bedrock of the Olkiluoto Island in the western end of the Palaeoproterozoic Svecofennian Accretionary Arc Complex, SW Finland is composed of high-grade metamorphic pelites, arenites and intermediate, arc type metavolcanic rocks intruded by granodioritic to tonalitic plutonic rocks. Regional metamorphism culminated with voluminous migmatization in the temperature of 660 - 700 deg C and relatively low pressure of about 3.5 - 4 kbar. The end result of polyphase metamorphism and deformation is a metamorphic rock succession composed of diverse migmatite rocks, metatexites and diatexites. Metatexites are migmatites in which several, discrete components can be detected, and in which the paleosome with some pre-partial-melting textures is identifiable. Diatexites are more advanced migmatites in which the pre-migmatization structures are often totally destroyed and the rock is dominated by different neosome components meaning leucosome, melanosome or mesosome. Based on the migmatite structures the metatexites of Olkiluoto have been classified into six subgroups. Dike-structured metatexites are composed of well preserved paleosome intruded by one single set of narrow, subparallel leucosome dikes which cover ca. 5 - 10 % of the whole rock volume. Net-structure is composed of a network of narrow leucosome dikes which show a reticulated structure in a plane section and cover less than 30 % of the whole rock volume. Breccia-structure is composed of angular or rounded paleosome blocks surrounded by moderate amount of leucosome. Patch-structure is composed of irregular leucosome patches which intruded the well preserved paleosome and compose typically 20 - 70 % of the rock volume. Layer-structure is characterized by more or less regular leucosome dikes sub-parallel to the foliation of the well preserved paleosome. Vein-structured metatexites and also diatexites include a set of pipe-like, longish leucosome veins most probably generated by synchronous melting and deformation

  14. Towards benchmarking an in-stream water quality model

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available A method of model evaluation is presented which utilises a comparison with a benchmark model. The proposed benchmarking concept is one that can be applied to many hydrological models but, in this instance, is implemented in the context of an in-stream water quality model. The benchmark model is defined in such a way that it is easily implemented within the framework of the test model, i.e. the approach relies on two applications of the same model code rather than the application of two separate model codes. This is illustrated using two case studies from the UK, the Rivers Aire and Ouse, with the objective of simulating a water quality classification, general quality assessment (GQA, which is based on dissolved oxygen, biochemical oxygen demand and ammonium. Comparisons between the benchmark and test models are made based on GQA, as well as a step-wise assessment against the components required in its derivation. The benchmarking process yields a great deal of important information about the performance of the test model and raises issues about a priori definition of the assessment criteria.

  15. Rock engineering in Finland

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    Contains a large collection of short articles concerned with tunnels and underground caverns and their construction and use. The articles are grouped under the following headings: use of the subsurface space; water supply; waste water services; energy management (includes articles on power stations, district heating and oil storage and an article on coal storage); multipurpose tunnels; waste disposal; transport; shelters; sporting and recreational amenities located in rock caverns; storage facilities; industrial, laboratory, and service facilities; rock foundations; tourism and culture; utilization of rock masses; research on the disposal of nuclear waste; training and research in the field of rock engineering; site investigation techniques; design of structures in rock; construction; the environment and occupational safety; modern equipment technology; underground space in Helsinki.

  16. Numerical Study on Dynamic Response of a Horizontal Layered-Structure Rock Slope under a Normally Incident Sv Wave

    Directory of Open Access Journals (Sweden)

    Zhifa Zhan

    2017-07-01

    Full Text Available Several post-earthquake investigations have indicated that the slope structure plays a leading role in the stability of rock slopes under dynamic loads. In this paper, the dynamic response of a horizontal layered-structure rock slope under harmonic Sv wave is studied by making use of the Fast Lagrangian Analysis of Continua method (FLAC. The suitability of FLAC for studying wave transmission across rock joints is validated through comparison with analytical solutions. After parametric studies on Sv wave transmission across the horizontal layered-structure rock slope, it is found that the acceleration amplification coefficient η, which is defined as the ratio of the acceleration at the monitoring point to the value at the toe, wavily increases with an increase of the height along the slope surface. Meanwhile, the fluctuation weakens with normalized joint stiffness K increasing and enhances with normalized joint spacing ξ increasing. The acceleration amplification coefficient of the slope crest ηcrest does not monotonously increase with the increase of ξ, but decreases with the increase of K. Additionally, ηcrest is more sensitive to ξ compared to K. From the contour figures, it can also be found that the contour figures of η take on rhythm, and the effects of ξ on the acceleration amplification coefficient are more obvious compared to the effects on K.

  17. The Structure of Performance of a Sport Rock Climber

    Science.gov (United States)

    Magiera, Artur; Roczniok, Robert; Maszczyk, Adam; Czuba, Miłosz; Kantyka, Joanna; Kurek, Piotr

    2013-01-01

    This study is a contribution to the discussion about the structure of performance of sport rock climbers. Because of the complex and multifaceted nature of this sport, multivariate statistics were applied in the study. The subjects included thirty experienced sport climbers. Forty three variables were scrutinised, namely somatic characteristics, specific physical fitness, coordination abilities, aerobic and anaerobic power, technical and tactical skills, mental characteristics, as well as 2 variables describing the climber’s performance in the OS (Max OS) and RP style (Max RP). The results show that for training effectiveness of advanced climbers to be thoroughly analysed and examined, tests assessing their physical, technical and mental characteristics are necessary. The three sets of variables used in this study explained the structure of performance similarly, but not identically (in 38, 33 and 25%, respectively). They were also complementary to around 30% of the variance. The overall performance capacity of a sport rock climber (Max OS and Max RP) was also evaluated in the study. The canonical weights of the dominant first canonical root were 0.554 and 0.512 for Max OS and Max RP, respectively. Despite the differences between the two styles of climbing, seven variables – the maximal relative strength of the fingers (canonical weight = 0.490), mental endurance (one of scales : The Formal Characteristics of Behaviour–Temperament Inventory (FCB–TI; Strelau and Zawadzki, 1995)) (−0.410), climbing technique (0.370), isometric endurance of the fingers (0.340), the number of errors in the complex reaction time test (−0.319), the ape index (−0.319) and oxygen uptake during arm work at the anaerobic threshold (0.254) were found to explain 77% of performance capacity common to the two styles. PMID:23717360

  18. Tectonic constraints on a deep-seated rock slide in weathered crystalline rocks

    Science.gov (United States)

    Borrelli, Luigi; Gullà, Giovanni

    2017-08-01

    Deep-seated rock slides (DSRSs), recognised as one of the most important mass wasting processes worldwide, involve large areas and cause several consequences in terms of environmental and economic damage; they result from a complex of controlling features and processes. DSRSs are common in Calabria (southern Italy) where the complex geo-structural setting plays a key role in controlling the geometry of the failure surface and its development. This paper describes an integrated multi-disciplinary approach to investigate a DSRS in Palaeozoic high-grade metamorphic rocks of the Sila Massif; it focuses on the definition of the internal structure and the predisposing factors of the Serra di Buda landslide near the town of Acri, which is a paradigm for numerous landslides in this area. An integrated interdisciplinary study based on geological, structural, and geomorphological investigations-including field observations of weathering grade of rocks, minero-petrographic characterisations, geotechnical investigations and, in particular, fifteen years of displacement monitoring-is presented. Stereoscopic analysis of aerial photographs and field observations indicate that the Serra di Buda landslide consists of two distinct compounded bodies: (i) an older and dormant body ( 7 ha) and (ii) a more recent and active body ( 13 ha) that overlies the previous one. The active landslide shows movement linked to a deep-seated translational rock slide (block slide); the velocity scale ranges from slow (1.6 m/year during paroxysmal stages) to extremely slow (affected by weathering processes that significantly reduce the rock strength and facilitate the extensive failure of the Serra di Buda landslide. Finally, the landslide's internal structure, according to geotechnical investigations and displacement monitoring, is proposed. The proposed approach and the obtained results can be generalised to typify other deep landslides in similar geological settings.

  19. Assessment of natural radioactivity levels in rocks and their relationships with the geological structure of Johor state, Malaysia.

    Science.gov (United States)

    Alnour, I A; Wagiran, H; Ibrahim, N; Hamzah, S; Elias, M S; Laili, Z; Omar, M

    2014-01-01

    The distribution of natural radionuclides ((238)U, (232)Th and (40)K) and their radiological hazard effect in rocks collected from the state of Johor, Malaysia were determined by gamma spectroscopy using a high-purity germanium detector. The highest values of (238)U, (232)Th and (40)K activity concentrations (67±6, 85±7 and 722±18 Bg kg(-1), respectively) were observed in the granite rock. The lowest concentrations of (238)U and (232)Th (2±0.1 Bq kg(-1) for (238)U and 2±0.1 Bq kg(-1) for (232)Th) were observed in gabbro rock. The lowest concentration of (40)K (45±2 Bq kg(-1)) was detected in sandstone. The radium equivalent activity concentrations for all rock samples investigated were lower than the internationally accepted value of 370 Bq kg(-1). The highest value of radium equivalent in the present study (239±17 Bq kg(-1)) was recorded in the area of granite belonging to an acid intrusive rock geological structure. The absorbed dose rate was found to range from 4 to 112 nGy h(-1). The effective dose ranged from 5 to 138 μSv h(-1). The internal and external hazard index values were given in results lower than unity. The purpose of this study is to provide information related to radioactivity background levels and the effects of radiation on residents in the study area under investigation. Moreover, the relationships between the radioactivity levels in the rocks within the geological structure of the studied area are discussed.

  20. Stream habitat analysis using the instream flow incremental methodology

    Science.gov (United States)

    Bovee, Ken D.; Lamb, Berton L.; Bartholow, John M.; Stalnaker, Clair B.; Taylor, Jonathan; Henriksen, Jim

    1998-01-01

    This document describes the Instream Flow Methodology in its entirety. This also is to serve as a comprehensive introductory textbook on IFIM for training courses as it contains the most complete and comprehensive description of IFIM in existence today. This should also serve as an official guide to IFIM in publication to counteract the misconceptions about the methodology that have pervaded the professional literature since the mid-1980's as this describes IFIM as it is envisioned by its developers. The document is aimed at the decisionmakers of management and allocation of natural resources in providing them an overview; and to those who design and implement studies to inform the decisionmakers. There should be enough background on model concepts, data requirements, calibration techniques, and quality assurance to help the technical user design and implement a cost-effective application of IFIM that will provide policy-relevant information. Some of the chapters deal with basic organization of IFIM, procedural sequence of applying IFIM starting with problem identification, study planning and implementation, and problem resolution.

  1. Retrogressive harmonic motion as structural and stylistic characteristic of pop-rock music

    Science.gov (United States)

    Carter, Paul S.

    The central issue addressed in this dissertation is that of progressive and retrogressive harmonic motion as it is utilized in the repertoire of pop-rock music. I believe that analysis in these terms may prove to be a valuable tool for the understanding of the structure, style and perception of this music. Throughout my study of this music, various patterns of progressive and retrogressive harmonic motions within a piece reveal a kind of musical character about it, a character on which much of a work's style, organization and extramusical nature often depends. Several influential theorists, especially Jean-Phillipe Rameau, Hugo Riemann, and Arnold Schoenberg, have addressed the issues of functional harmony and the nature of the motion between chords of a tonal harmonic space. After assessing these views, I have found that it is possible to differentiate between two fundamental types of harmonic motions. This difference, one that I believe is instrumental in characterizing pop-rock music, is the basis for the analytical perspective I wish to embrace. After establishing a method of evaluating tonal harmonic root motions in these terms, I wish to examine a corpus of this music in order to discover what a characterization of its harmonic motion may reveal about each piece. Determining this harmonic character may help to establish structural and stylistic traits for that piece, its genre, composer, period, or even its sociological purpose. Conclusions may then be drawn regarding the role these patterns play in defining musical style traits of pop-rock. Partly as a tool for serving the study mentioned above I develop a graphical method of accounting for root motion I name the tonal "Space-Plot"; This apparatus allows the analyst to measure several facets about the harmonic motion of the music, and to see a wide scope of relations in and around a diatonic key.

  2. Coupled vertical-rocking response of base-isolated structures

    International Nuclear Information System (INIS)

    Pan, T.C.; Kelly, J.M.

    1984-01-01

    A base-isolated building can have a small horizontal eccentricity between the center of mass of the superstructure and the center of rigidity of the supporting bearings. The structure can be modeled as a rigid block with tributary masses supported on massless rubber bearings placed at a constant elevation below the center of mass. Perturbation methods are implemented to find the dynamic characteristics for both the detuned and the perfectly tuned cases. The Green's functions for the displacement response of the system are derived for the undamped and the damped conditions. The response spectrum modal superposition method is used in estimating the maximum acceleration. A simple method, accounting for the effect of closely spaced modes, is proposed for combining modal maxima and results in an approximate single-degree-of-freedom solution. This approximate solution may be used for thepreliminary design of a base-isolated structure. Numerical results for a base-isolated building subjected to the vertical component of the El Centro earthquake of 1940 were carried out for comparison with analytical results. It is shown that the effect of rocking coupling on the vertical seismic response of baseisolated structures can generally be neglected because of the combined effects of the time lag between the maximum translational and rotational responses and the influence of damping in the isolation system

  3. Rock types and ductile structures on a rock domain basis, and fracture orientation and mineralogy on a deformation zone basis. Preliminary site description. Forsmark area - version 1.2

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, Michael [Geological Survey of Sweden, Uppsala (Sweden); Forssberg, Ola [Golder Associates AB, Uppsala (Sweden)

    2006-09-15

    This report presents the results of the analysis of base geological data in order to establish the dominant rock type, the subordinate rock types and the orientation of ductile mineral fabrics within each rock domain included in the regional geological model, version 1.2. An assessment of the degree of homogeneity of each domain is also provided. The analytical work has utilised the presentation of data in the form of histograms and stereographic projections. Fisher means and K values or best-fit great circles and corresponding pole values have been calculated for the ductile structural data. These values have been used in the geometric modelling of rock domains in the regional model, version 1.2. Furthermore, all analytical results have been used in the assignment of properties to rock domains in this model. A second analytical component reported here addresses the orientation and mineralogy of fractures in the deterministic deformation zones that are included in the regional geological model, version 1.2. The analytical work has once again utilised the presentation of data in the form of histograms and stereographic projections. Fisher means and K values are presented for the orientation of fracture sets in the deterministic deformation zones that have been identified with the help of new borehole data. The frequencies of occurrence of different minerals along the fractures in these deformation zones as well as the orientation of fractures in the zones, along which different minerals occur, are also presented. The results of the analyses have been used in the establishment of a conceptual structural model for the Forsmark site and in the assignment of properties to deterministic deformation zones in model version 1.2.

  4. A system of nomenclature for rocks in Olkiluoto

    International Nuclear Information System (INIS)

    Mattila, J.

    2006-06-01

    Due to international interest in the Finnish deep repository project at Olkiluoto (SW Finland) and the need for collaboration between scientists involved in site investigations for the disposal of spent nuclear fuel in other countries, a well-documented system of rock nomenclature is required, based on existing classification schemes and international recommendations. The BGS (British Geological Survey) rock classification scheme is the most comprehensive rock classification scheme and the basic principles behind it are utilised for the system of nomenclature for rocks in Olkiluoto. The BGS classification system is based on the use of descriptive names and a clear hierarchy, making it possible to classify rocks at different levels depending on the specific goals of the study, the level of available information, and the expertise of the user. Each rock type is assigned a root name, which is based on structural and textural characteristics or modal compositions of the rock and the root names are refined with qualifier terms as prefixes. Qualifier terms refer to the structure or modal composition of the rock. The bedrock at the Olkiluoto site consists of metamorphic and igneous rocks. The metamorphic rocks consist of migmatitic gneisses and (non-migmatitic) gneisses, which are further divided according to their structural characteristics and modal compositions, the former into stromatic, veined, diatexitic gneisses, the latter into mica, quartz, mafic and TGG gneisses. Igneous rocks consist of pegmatitic granites, K-feldspar porphyry and diabases. (orig.)

  5. Development of artificial soft rock

    International Nuclear Information System (INIS)

    Kishi, Kiyoshi

    1995-01-01

    When foundation base rocks are deeper than the level of installing structures or there exist weathered rocks and crushed rocks in a part of base rocks, often sound artificial base rocks are made by substituting the part with concrete. But in the construction of Kashiwazaki Kariwa Nuclear Power Station of Tokyo Electric Power Co., Inc., the foundation base rocks consist of mudstone, and the stiffness of concrete is large as compared with the surrounding base rocks. As the quality of the substituting material, the nearly same stiffness as that of the surrounding soft rocks and long term stability are suitable, and the excellent workability and economical efficiency are required, therefore, artificial soft rocks were developed. As the substituting material, the soil mortar that can obtain the physical property values in stable form, which are similar to those of Nishiyama mudstone, was selected. The mechanism of its hardening and the long term stability, and the manufacturing plant are reported. As for its application to the base rocks of Kashiwazaki Kariwa Nuclear Power Station, the verification test at the site and the application to the base rocks for No. 7 plant reactor building and other places are described. (K.I.)

  6. In-Stream Sediment Dynamics for predicted environmental concentration calculations of plant protection products in the FOCUSSW Scenarios

    Science.gov (United States)

    Strehmel, Alexander; Erzgräber, Beate; Gottesbüren, Bernhard

    2016-04-01

    The exposure assessment for the EU registration procedure of plant protection products (PPP), which is based on the 'Forum for the co-ordination of pesticide fate models and their use' (FOCUS), currently considers only periods of 12-16 months for the exposure assessment in surface water bodies. However, in a recent scientific opinion of the European Food Safety Authority (EFSA) it is argued that in a multi-year exposure assessment, the accumulation of PPP substances in river sediment may be a relevant process. Therefore, the EFSA proposed to introduce a sediment accumulation factor in order to account for enrichment of PPP substances over several years in the sediment. The calculation of this accumulation factor, however, would consider degradation in sediment as the only dissipation path, and does not take into account riverine sediment dynamics. In order to assess the influence of deposition and the possible extent of substance accumulation in the sediment phase, the hydraulic model HEC-RAS was employed for an assessment of in-stream sediment dynamics of the FOCUS stream scenarios. The model was parameterized according to the stream characteristics of the FOCUS scenarios and was run over a period of 20 years. The results show that with the distribution of grain sizes and the ranges of flow velocity in the FOCUS streams the main sediment process in the streams is transport. First modeling results suggest that about 80% of the eroded sediment mass from the adjacent field are transported to the downstream end of the stream and out of the system, while only about 20% are deposited in the river bed. At the same time, only about 30% of in-stream sediment mass stems from the adjacent field and is associated with PPP substance, while the remaining sediment consists of the substance-free base sediment concentration regarded in the scenarios. With this, the hydraulic modelling approach is able to support the development of a meaningful sediment accumulation factor by

  7. Technique for large-scale structural mapping at uranium deposits i in non-metamorphosed sedimentary cover rocks

    International Nuclear Information System (INIS)

    Kochkin, B.T.

    1985-01-01

    The technique for large-scale construction (1:1000 - 1:10000), reflecting small amplitude fracture plicate structures, is given for uranium deposits in non-metamorphozed sedimentary cover rocks. Structure drill log sections, as well as a set of maps with the results of area analysis of hidden disturbances, structural analysis of iso-pachous lines and facies of platform mantle horizons serve as sour ce materials for structural mapplotting. The steps of structural map construction are considered: 1) structural carcass construction; 2) reconstruction of structure contour; 3) time determination of structure initiation; 4) plotting of an additional geologic load

  8. COMPREHENSIVE ANALYSIS ON SEEPAGE AND STRUCTURAL STABILITY OF EARTH-ROCK DAM: A CASE STUDY OF XIQUANYAN DAM IN CHINA

    Directory of Open Access Journals (Sweden)

    Qingqing GUO

    2016-07-01

    Full Text Available Earth-rock dam is commonly used in the high-dam engineering around the world. It has been widely accepted that the analysis on structural and seepage stability plays a very important role, and it is necessary to take into account while designing the earth-rock dam. In performing the analysis of structural and seepage stability, many remarkable methods are available at current stage. However, there are still some important issues remaining unsolved, including: (1 Finite element methods (FEMs is a means of solutions to analysis seepage process, but it is often a difficult task to determine the so-called seepage coefficient, because the common-used water injection test is limited in the practical work due to the high cost and complex procedure. (2 It has long been discussed that the key parameters for structural stability analysis show a significant spatial and temporal variations. It may be partly explained by the inhomogeneous dam-filling during construction work and the developing seepage process. The consequence is that one constant value of the parameter cannot represent the above variations. In this context, we solve the above issues and introduce the solution with a practical earth-rock dam project. For determining the seepage coefficient, the data from the piezo metric tube is used to calculate the potential value, based on which the seepage coefficient can be back-analysed. Then the seepage field, as well as the seepage stability are numerically analysed using the FEM-based SEEP/W program. As to the structural safety, we take into account the spatial and temporal variations of the key parameters, and incorporate the Monte-Carlo simulation method into the commonly used M-P method to calculate the frequency distribution of the obtained structural safety factor. In this way, the structural and seepage safety can be well analysed. This study is also beneficial to provide a mature method and a theoretical insight into the earth-rock dam design

  9. A new MONERIS in-Stream Retention Module to Account Nutrient Budget of a Temporary River in Cyprus

    OpenAIRE

    TZORAKI Ourania; COOPER David; DÖRFLINGER Gerald; PANAGOS Panagiotis

    2014-01-01

    The nature of the nutrient budget for temporary rivers differs from that for permanent rivers because of the restricted nature of flow, the lack of adequate dilution, and weather conditions which are conducive to the development of algal blooms. We analyse the nutrient budget of three tributaries of a temporary river in Cyprus, the Kouris, with the aid of the MONERIS model. MONERIS in-stream retention module was modified to account for a 1-dimensional advection - dispersion pollutants transpo...

  10. Superconductivity of Rock-Salt Structure LaO Epitaxial Thin Film.

    Science.gov (United States)

    Kaminaga, Kenichi; Oka, Daichi; Hasegawa, Tetsuya; Fukumura, Tomoteru

    2018-06-06

    We report a superconducting transition in a LaO epitaxial thin film with the superconducting transition onset temperature ( T c ) at around 5 K. This T c is higher than those of other lanthanum monochalcogenides and opposite to their chemical trend: T c = 0.84, 1.02, and 1.48 K for LaX (X = S, Se, Te), respectively. The carrier control resulted in a dome-shaped T c as a function of electron carrier density. In addition, the T c was significantly sensitive to epitaxial strain in spite of the highly symmetric crystal structure. This rock-salt superconducting LaO could be a building block to design novel superlattice superconductors.

  11. Seismic behavior of NPP structures subjected to realistic 3D, inclined seismic motions, in variable layered soil/rock, on surface or embedded foundations

    International Nuclear Information System (INIS)

    Jeremić, B.; Tafazzoli, N.; Ancheta, T.; Orbović, N.; Blahoianu, A.

    2013-01-01

    Highlights: • Full 3D, inclined, incoherent seismic motions used for modeling SSI of an NPP. • Analyzed effects of variable and uniform soil/rock layering profiles on SSI. • Surface and embedded foundations were modeled and differences analyzed. - Abstract: Presented here is an investigation of the seismic response of a massive NPP structures due to full 3D, inclined, un-correlated input motions for different soil and rock profiles. Of particular interest are the effects of soil and rock layering on the response and the changes of input motions (frequency characteristics) due to such layering. In addition to rock/soil layering effects, investigated are also effects of foundation embedment on dynamic response. Significant differences were observed in dynamic response of containment and internal structure founded on surface and on embedded foundations. These differences were observed for both rock and soil profiles. Select results are used to present most interesting findings

  12. The geochemistry and geochronology of some proterozoic granitoid rocks from the Natal structural and metamorphic province, Southeastern Africa

    International Nuclear Information System (INIS)

    Kerr, A.; Milne, G.C.; Eglington, B.M.

    1987-01-01

    The Natal Structural and Metamorphic Province is thought to be an eastern extension of the Namaqua Metamorphic Province. Until recently few geochemical and isotopic data have been available on many of the rocks of this mobile belt. This paper presentes initial geochemical and geochronological information on the granitoids and associated rocks from three areas NSMP. Together, these areas provide a traverse through central and southern parts of the Mapumulo Group. Supracrustal gneisses, of uncertain age, are the oldest rocks in all areas, while the granitic intrusives range from 1,200-850 Ma, with a tendency for younger dates towards dates towards the south. Low initial 87 Sr/ 86 Sr ratios for these plutonic units suggest that the rocks were the products of partial melting of a relatively juvenile (circa 1,400 Ma) protolith. A type granites are common within the NSMP and give a range of ages, indicating that conditions suitable for their formation persited in this part of the African continent for an extended period of time. Economic deposits are lacking in eastern (Natal) sector of the mobile belt. Reconnaissance studies, however indicate that syn-tolate-Kinematic granitoids, intruded circa 1,000 Ma, are enriched in uranium and thorium irrespective of bulk chemistry, textural nature,mineralogy,structural setting, and isotopic characteristics. (author) [pt

  13. The catazonal poly-metamorphic rocks of Cabo Ortegal (NW Spain), a structural and petrofabric study

    NARCIS (Netherlands)

    Engels, J.P.

    1972-01-01

    The petrological study of the southern part of the Cabo Ortegal area is a complement of Vogel’s (1967) investigation of the northern half. The present investigations include a structural as well as a petrofabric study. The rocks belong to an eugeosynclinal sequence which during the Precambrian

  14. Highly Shocked Low Density Sedimentary Rocks from the Haughton Impact Structure, Devon Island, Nunavut, Canada

    Science.gov (United States)

    Osinski, G. R.; Spray, J. G.

    2001-01-01

    We present the preliminary results of a detailed investigation of the shock effects in highly shocked, low density sedimentary rocks from the Haughton impact structure. We suggest that some textural features can be explained by carbonate-silicate immiscibility. Additional information is contained in the original extended abstract.

  15. Numerical analysis of the performance of rock weirs: Effects of structure configuration on local hydraulics

    Science.gov (United States)

    Holmquist-Johnson, C. L.

    2009-01-01

    River spanning rock structures are being constructed for water delivery as well as to enable fish passage at barriers and provide or improve the aquatic habitat for endangered fish species. Current design methods are based upon anecdotal information applicable to a narrow range of channel conditions. The complex flow patterns and performance of rock weirs is not well understood. Without accurate understanding of their hydraulics, designers cannot address the failure mechanisms of these structures. Flow characteristics such as jets, near bed velocities, recirculation, eddies, and plunging flow govern scour pool development. These detailed flow patterns can be replicated using a 3D numerical model. Numerical studies inexpensively simulate a large number of cases resulting in an increased range of applicability in order to develop design tools and predictive capability for analysis and design. The analysis and results of the numerical modeling, laboratory modeling, and field data provide a process-based method for understanding how structure geometry affects flow characteristics, scour development, fish passage, water delivery, and overall structure stability. Results of the numerical modeling allow designers to utilize results of the analysis to determine the appropriate geometry for generating desirable flow parameters. The end product of this research will develop tools and guidelines for more robust structure design or retrofits based upon predictable engineering and hydraulic performance criteria. ?? 2009 ASCE.

  16. Simquake 3: Seismic interactions between building structures and rock-socketed foundations: Final report

    International Nuclear Information System (INIS)

    Howard, G.E.; Chitty, D.E.; Oleck, R.F.

    1988-04-01

    It has long been recognized that soil-structure interaction can significantly influence the earthquake response of massive structures such as nuclear power plant reactor buildings. The linear analysis methods that are widely used to model interaction phenomena can result in often unrecognized safety margins in design for earthquake excitation. Use of improved interaction models which capture nonlinear characteristics of interaction---such as energy dissipation and significant changes in stiffness---can provide realistic predictions of the earthquake loads imposed on nuclear power plant structures and equipment, supplying an improved basis for seismic design review. This report documents the results of a research effort investigating the soil-structure (or structure-media) interaction of reinforced concrete structures founded in backfilled rock sockets. The objectives of the research, which included field testing with semi-scale structural models, were: to examine the influence of the backfilled socket on structural dynamic response; and to develop an experimental data base for the benchmarking of computer simulation procedures

  17. Effects of explosions in hard rocks

    International Nuclear Information System (INIS)

    Heuze, F.E.; Walton, O.R.; Maddix, D.M.; Shaffer, R.J.; Butkovich, T.R.

    1993-01-01

    This work relates to explosions in hard rocks (ex: basalt, granite, limestone...). Hard rock masses typically have a blocky structure created by the existence of geologic discontinuities such as bedding contacts, faults, and joints. At very high pressure - hundreds of kilobars and above - these discontinuities do not act separately, and the rock appears to be an equivalent continuous medium. At stress of a few tens of kilobars and below, the geologic discontinuities control the kinematics of the rock masses. Hence, the simulation of rock dynamics, anywhere but in the very-near source region, should account for those kinematics

  18. Modeling Climate and Management Change Impacts on Water Quality and In-Stream Processes in the Elbe River Basin

    Directory of Open Access Journals (Sweden)

    Cornelia Hesse

    2016-01-01

    Full Text Available Eco-hydrological water quality modeling for integrated water resources management of river basins should include all necessary landscape and in-stream nutrient processes as well as possible changes in boundary conditions and driving forces for nutrient behavior in watersheds. The study aims to assess possible impacts of the changing climate (ENSEMBLES climate scenarios and/or land use conditions on resulting river water quantity and quality in the large-scale Elbe river basin by applying a semi-distributed watershed model of intermediate complexity (SWIM with implemented in-stream nutrient (N+P turnover and algal growth processes. The calibration and validation results revealed the ability of SWIM to satisfactorily simulate nutrient behavior at the watershed scale. Analysis of 19 climate scenarios for the whole Elbe river basin showed a projected increase in temperature (+3 °C and precipitation (+57 mm on average until the end of the century, causing diverse changes in river discharge (+20%, nutrient loads (NO3-N: −5%; NH4-N: −24%; PO4-P: +5%, phytoplankton biomass (−4% and dissolved oxygen concentration (−5% in the watershed. In addition, some changes in land use and nutrient management were tested in order to reduce nutrient emissions to the river network.

  19. Centrifuge Testing and Seismic Response Analysis for Uplift Behavior of Spread Foundation Structures on Rock

    Directory of Open Access Journals (Sweden)

    Takuya Suzuki

    2016-09-01

    Full Text Available The uplift behavior of structures subjected to severe seismic motion has not been clarified. This paper presents experimental and analytical studies conducted for clarifying this problem of spread foundation structures on rock. First, centrifugal loading tests are conducted to determine the uplift behavior of these structures, and the uplift behavior of these structures is confirmed. Then, simulation analyses are performed using a three-dimensional FE model and the accuracy of these analyses is confirmed. A comparison between test and analyses results clarified the important analytical conditions required for maintaining analysis precision and the limit of analysis precision.

  20. Rock stress measurements in the Grimsel Underground Rock Laboratory and their geological interpretation

    International Nuclear Information System (INIS)

    Braeuer, V.; Heusermann, S.; Pahl, A.

    1989-01-01

    Rock stress is being studied as part of the Swiss-German cooperation between the National Cooperative for the Storage of Radioactive Waste (NAGRA), the Research Centre for Environmental Sciences (GSF), and the Federal Institute for Geosciences and Natural Resources (BGR) in the Grimsel Rock Laboratory in Switzerland. Several methods and various equipment for measuring rock stress have been developed and tested in an approximately 200-m borehole drilled from a gallery at a depth of 450 m. The measurements were made continually during overcoring; the data were recorded and processed in a computer located downhole or outside the borehole. The results of the overcoring tests and of frac tests indicate a principle horizontal stress of 25-40 MPa, directed mainly NW-SE. Detailed geological mapping shows relationships between stress and rock structure. A zone of nearly unfractured rock exhibits an increase in stress and a change in stress direction. (orig.)

  1. Influence of different geological structures on stress–strain state of hard rock mass

    Science.gov (United States)

    Kuznetzov, NN; Fedotova, YuV

    2018-03-01

    The results of numerical simulation of stress–strain state in a hard rock mass area with the complex geological structures are presented. The variants of the stress value change are considered depending on the boundary conditions and physical properties of the model blocks. Furthermore, the possibility of in-situ stress formation under the influence of energy coming from the deeper Earth’s layers is demonstrated in terms of the Khibiny Massif.

  2. Application of Confined Blasting in Water-Filled Deep Holes to Control Strong Rock Pressure in Hard Rock Mines

    Directory of Open Access Journals (Sweden)

    Jingxuan Yang

    2017-11-01

    Full Text Available In extra-thick coal seams, mining operations can lead to large-scale disturbances, complex overburden structures, and frequent and strong strata behavior in the stope, which are serious threats to mine safety. This study analyzed the overburden structure and strata behavior and proposed the technique of confined blasting in water-filled deep holes as a measure to prevent strong rock pressure. It found that there are two primary reasons for the high effectiveness of the proposed technique in presplitting hard coal and rock. First, the fracture water enables much more efficient transfer of dynamic load due to its incompressibility. Second, the subsequent expansion of water can further split the rock by compression. A mechanical model was used to reveal how the process of confined blasting in water-filled deep holes presplit roof. Moreover, practical implementation of this technique was found to improve the structure of hard, thick roof and prevent strong rock pressure, demonstrating its effectiveness in roof control.

  3. Distribution of siderophile and other trace elements in melt rock at the Chicxulub impact structure

    Science.gov (United States)

    Schuraytz, B. C.; Lindstrom, D. J.; Martinez, R. R.; Sharpton, V. L.; Marin, L. E.

    1994-01-01

    Recent isotopic and mineralogical studies have demonstrated a temporal and chemical link between the Chicxulub multiring impact basin and ejecta at the Cretaceous-Tertiary boundary. A fundamental problem yet to be resolved, however, is identification of the projectile responsible for this cataclysmic event. Drill core samples of impact melt rock from the Chichxulub structure contain Ir and Os abundances and Re-Os isotopic ratios indicating the presence of up to approx. 3 percent meteoritic material. We have used a technique involving microdrilling and high sensitivity instrumental neutron activation analysis (INAA) in conjunction with electron microprobe analysis to characterize further the distribution of siderophile and other trace elements among phases within the C1-N10 melt rock.

  4. Solid as a rock

    International Nuclear Information System (INIS)

    Pincus, H.J.

    1984-01-01

    Recent technologic developments have required a more comprehensive approach to the behavior of rock mass or rock substance plus discontinuities than was adequate previously. This work considers the inherent problems in such operations as the storage of hot or cold fluids in caverns and aquifers, underground storage of nuclear waste, underground recovery of heat from hydrocarbon fuels, tertiary recovery of oil by thermal methods, rapid excavation of large openings at shallow to great depths and in hostile environments, and retrofitting of large structures built on or in rock. The standardization of methods for determining rock properties is essential to all of the activities described, for use not only in design and construction but also in site selection and post-construction monitoring. Development of such standards is seen as a multidisciplinary effort

  5. Mineralogical and structural transformations related to alterations in hydrothermal and climatological conditions of basic vulcanic rocks from northern Parana (Ribeirao Preto region, SP, Brazil)

    International Nuclear Information System (INIS)

    Goncalves, N.M.M.

    1987-01-01

    Detailed studies of the basic vulcanic rocks of northern Parana basin (Region of Ribeirao Preto, SP) reveled that these rocks were affected by pre-meteoric activity (hydrothermal alteration) before being exposed to the supergene system of alteration linked to the lithosphere/atmosphere interface. Mineralogical and structural transformation are studied. The appearance of sequential crystalline-chemical paragenesis in zones suggest that the hydrothermal activity occurred during two successives processes of alteration: the expulsion of the water from the rock during the later stages of magma cooling and the continous process of dissolution of the rock wall and the ionic diffusion involving the rock sistem of structural voids. The hydro-thermal action was followed by weathering action developing a thin 'front' of superficial alteration. This alteration system, can lead to the formation of three major levels of alteration horizons and superficial accumulations: alterites, glebular and suil surface materials. (C.D.G.) [pt

  6. Assessing the Performance of In-Stream Restoration Projects Using Radio Frequency Identification (RFID Transponders

    Directory of Open Access Journals (Sweden)

    Bruce MacVicar

    2015-10-01

    Full Text Available Instream channel restoration is a common practice in river engineering that presents a challenge for research. One research gap is the development of monitoring techniques that allow for testable predictions of sediment transport and supply. Here we use Radio Frequency Identification (RFID transponders to compare the short-term (1-year sediment transport response to flood events in a restored and a control reach. The field site is Wilket Creek, an enlarged creek in a fully urbanized catchment without stormwater management control in Toronto, Ontario. The responses to three flooding periods, each of which are at or above the design bankfull discharge, are described. Key results are that (i particle mobility is lower in the restored reach for all three periods; (ii full mobility occurs in the control reach during the first two floods while partial mobility occurs in the restored reach; and (iii the constructed morphology exerted a controlling influence on particle entrainment, with higher mobility in the pools. Log-transformed travel distances exhibit normal distributions when grouped by particle size class, which allows a statistical comparison with power law and other predictive travel-distance relations. Results show that three bedload transport conditions can occur, with partial mobility associated with a mild relation between particle size and travel distance and full mobility associated with either a flat or steep relation depending on the degree of integration of particles in the bed. Recommendations on seeding strategy and sample sizes are made to improve the precision of the results by minimizing confidence intervals for mobility and travel distances. Even in a short term study, the RFID sediment tracking technique allows a process-based assessment of stream restoration outcomes that can be used to justify the instream intervention and plan future attempts to stabilize and enhance the system.

  7. Increasing in-stream nitrogen concentrations under different bioenergy crop management practices in central Germany

    Science.gov (United States)

    Jomaa, Seifeddine; Thraen, Daniela; Rode, Michael

    2015-04-01

    Understanding how nitrogen fluxes respond to changes in land use and agriculture practices is crucial for improving instream water quality prediction. In central Germany, expansion of bioenergy crops such as maize and rape for ethanol production during the last decade led to increasing of fertilizer application rates. To examine the effect of these changes, surface water quality of a drinking water reservoir catchment was investigated for more than 30 years. The Weida catchment (99.5 km2) is part of the Elbe river basin and has a share of 67% agricultural land use with significant changes in agricultural practices within the investigation period. For the period 2004-2012, the share of maize and rape has been increased by 52% and 20%, respectively, for enhancing bioenergy production. To achieve our gaols, the semi-distributed hydrological water quality HYPE (Hydrological Predictions for the Environment) model was calibrated for discharge and inorganic nitrogen concentrations (IN) during the period 1997-2000.The model was validated successfully (with lowest performance of NSE = 0.78 and PBIAS = 3.74% for discharge) for three different periods 1983-1987, 1989-1996 and 2000-2003, which are charaterized by different fertilizer application rates. Results showed that the HYPE model reproduced reasonably well discharge and IN daily loads (with lowest NSE = 0.64 for IN-load). In addition, the HYPE model was evaluated successfully to predict the discharge and IN concentrations for the period 2004-2012, where detailed input data in terms of crops management (field-specific survey) have been considered. Land use and crop rotations scenarios, with high hypothetical percentage of acceptance by the farmers, revealed that continuous conversion of agricultural land into bioenergy crops, will most likely, lead to an enrichment of in-stream nitrogen, especially after spring storms.

  8. Cecal bacterial communities in wild Japanese rock ptarmigans and captive Svalbard rock ptarmigans.

    Science.gov (United States)

    Ushida, Kazunari; Segawa, Takahiro; Tsuchida, Sayaka; Murata, Koichi

    2016-02-01

    Preservation of indigenous gastrointestinal microbiota is deemed to be critical for successful captive breeding of endangered wild animals, yet its biology is poorly understood. Here, we investigated cecal bacterial communities in wild Japanese rock ptarmigans (Lagopus muta japonica) and compared them with those in Svalbard rock ptarmigans (L. m. hyperborea) in captivity. Ultra-deep sequencing of 16S rRNA gene indicated that the community structure of cecal microbiota in wild rock ptarmigans was remarkably different from that in captive Svalbard rock ptarmigans. Fundamental differences between bacterial communities in the two groups of birds were detected at the phylum level. Firmicutes, Actinobacteria, Bacteroidetes and Synergistetes were the major phyla detected in wild Japanese rock ptarmigans, whereas Firmicutes alone occupied more than 80% of abundance in captive Svalbard rock ptarmigans. Furthermore, unclassified genera of Coriobacteriaceae, Synergistaceae, Bacteroidaceae, Actinomycetaceae, Veillonellaceae and Clostridiales were the major taxa detected in wild individuals, whereas in zoo-reared birds, major genera were Ruminococcus, Blautia, Faecalibacterium and Akkermansia. Zoo-reared birds seemed to lack almost all rock ptarmigan-specific bacteria in their intestine, which may explain the relatively high rate of pathogenic infections affecting them. We show evidence that preservation and reconstitution of indigenous cecal microflora are critical for successful ex situ conservation and future re-introduction plan for the Japanese rock ptarmigan.

  9. Electronic Structure of the Metastable Epitaxial Rock-Salt SnSe {111} Topological Crystalline Insulator

    Directory of Open Access Journals (Sweden)

    Wencan Jin

    2017-10-01

    Full Text Available Topological crystalline insulators have been recently predicted and observed in rock-salt structure SnSe {111} thin films. Previous studies have suggested that the Se-terminated surface of this thin film with hydrogen passivation has a reduced surface energy and is thus a preferred configuration. In this paper, synchrotron-based angle-resolved photoemission spectroscopy, along with density functional theory calculations, is used to demonstrate that a rock-salt SnSe {111} thin film epitaxially grown on Bi_{2}Se_{3} has a stable Sn-terminated surface. These observations are supported by low-energy electron diffraction (LEED intensity-voltage measurements and dynamical LEED calculations, which further show that the Sn-terminated SnSe {111} thin film has undergone a surface structural relaxation of the interlayer spacing between the Sn and Se atomic planes. In sharp contrast to the Se-terminated counterpart, the observed Dirac surface state in the Sn-terminated SnSe {111} thin film is shown to yield a high Fermi velocity, 0.50×10^{6}  m/s, which suggests a potential mechanism of engineering the Dirac surface state of topological materials by tuning the surface configuration.

  10. Rock stresses (Grimsel rock laboratory)

    International Nuclear Information System (INIS)

    Pahl, A.; Heusermann, S.; Braeuer, V.; Gloeggler, W.

    1989-01-01

    On the research and development project 'Rock Stress Measurements' the BGR has developed and tested several test devices and methods at GTS for use in boreholes at a depth of 200 m and has carried out rock mechanical and engineering geological investigations for the evaluation and interpretation of the stress measurements. The first time a computer for data processing was installed in the borehole together with the BGR-probe. Laboratory tests on hollow cylinders were made to study the stress-deformation behavior. To validate and to interprete the measurement results some test methods were modelled using the finite-element method. The dilatometer-tests yielded high values of Young's modulus, whereas laboratory tests showed lower values with a distinct deformation anisotropy. Stress measurements with the BGR-probe yielded horizontal stresses being higher than the theoretical overburden pressure and vertical stresses which agree well with the theoretical overburden pressure. These results are comparable to the results of the hydraulic fracturing tests, whereas stresses obtained with CSIR-triaxial cells are generally lower. The detailed geological mapping of the borehole indicated relationships between stress and geology. With regard to borehole depth different zones of rock structure joint frequency, joint orientation, and orientation of microfissures as well as stress magnitude, stress direction, and degree of deformation anisotropy could be distinguished. (orig./HP) [de

  11. Field Monitoring of Deformations and Internal Forces of Surrounding Rocks and Lining Structures in the Construction of the Gangkou Double-Arched Tunnel—A Case Study

    Directory of Open Access Journals (Sweden)

    Qixiang Yan

    2017-02-01

    Full Text Available Double-arched tunnel is a special and complex underground structure which needs to be monitored carefully during construction. Taking the Gangkou tunnel as the engineering background, this paper presents a case study of field monitoring of a representative double-arched tunnel. Typical cross sections were chosen in each class of surrounding rock masses in the tunnel area and different types of sensors were embedded in designed locations, and the deformations and forces of both surrounding rocks and lining structures were monitored systematically. The dynamic evolution as well as the spatial distribution characteristics of the monitoring data including the internal displacements of surrounding rocks and the contact pressures between surrounding rocks and primary linings, the axial forces in rock bolts and the internal forces in both steel arches and secondary linings were analyzed. The monitoring and analysis results show that the deformations and forces of both surrounding rocks and lining structures are directly related to the construction procedures, geological conditions and locations in the double-arched tunnel. According to the results, some reasonable suggestions were provided for the improvement of the tunnel construction. This study will provide useful reference and guidance for the design, construction and monitoring of similar engineering projects in future.

  12. Strategic planning for instream flow restoration: a case study of potential climate change impacts in the central Columbia River basin.

    Science.gov (United States)

    Donley, Erin E; Naiman, Robert J; Marineau, Mathieu D

    2012-10-01

    We provide a case study prioritizing instream flow restoration activities by sub-basin according to the habitat needs of Endangered Species Act (ESA)-listed salmonids relative to climate change in the central Columbia River basin in Washington State (USA). The objective is to employ scenario analysis to inform and improve existing instream flow restoration projects. We assess the sensitivity of late summer (July, August, and September) flows to the following scenario simulations - singly or in combination: climate change, changes in the quantity of water used for irrigation and possible changes to existing water resource policy. Flows for four sub-basins were modeled using the Water Evaluation and Planning system (WEAP) under historical and projected conditions of 2020 and 2040 for each scenario. Results indicate that Yakima will be the most flow-limited sub-basin with average reductions in streamflow of 41% under climate conditions of 2020 and 56% under 2040 conditions; 1.3-2.5 times greater than those of other sub-basins. In addition, irrigation plays a key role in the hydrology of the Yakima sub-basin - with flow reductions ranging from 78% to 90% under severe to extreme (i.e., 20-40%) increases in agricultural water use (2.0-4.4 times the reductions in the other sub-basins). The Yakima and Okanogan sub-basins are the most responsive to simulations of flow-bolstering policy change (providing salmon with first priority water allocation and at biologically relevant flows), as demonstrated by 91-100% target flows attained. The Wenatchee and Methow sub-basins do not exhibit similar responsiveness to simulated policy changes. Considering climate change only, we conclude that flow restoration should be prioritized first in the Yakima and Wenatchee sub-basins, and second in the Okanogan and Methow. Considering both climate change and possible policy changes, we recommend that the Yakima sub-basin receive the highest priority for flow restoration activities to sustain

  13. New Investigations of the Gow Lake Impact Structure, Saskatchewan, Canada: Impact Melt Rocks, Astronaut Training, and More

    Science.gov (United States)

    Osinski, G. R.; Singleton, A. C.; Ozaruk, A.; Hansen, J. R.

    2012-03-01

    New investigations of the Gow Lake impact structure has revealed an almost complete sequence of impactites from the crater floor upward through a series of melt-free and melt-bearing rocks. This research involved an astronaut training component.

  14. An investigation of fine structure of the bursts produced by muons in the rock

    International Nuclear Information System (INIS)

    Higashi, S.; Kajino, F.; Nakashita, M.; Osaki, S.; Takahashi, T.; Yamamoto, S.

    1981-01-01

    Two dimensional lateral structures of the shower particles in the bursts, produced by high energy muons in the rock, have been studied by using the four layers of proportional counters. The mean lateral distributions measured fit well to those of Monte Carlo simulation of electromagnetic cascade showers. The distributions of reduced chi 2 which correspond to the fluctuations of each lateral distribution from the mean value show that the rates of the events giving high chi 2 for the data are somewhat greater than those expected from the simulation. The rates of these excesses to the total events are about 10% in the burst size range 578 - 8277 particles which are induced by the muons in the energy range 714 - 9900 GeV. These excesses could be explained by the contributions from the muon nuclear interactions in the rock

  15. Development and testing of an in-stream phosphorus cycling model for the soil and water assessment tool.

    Science.gov (United States)

    White, Michael J; Storm, Daniel E; Mittelstet, Aaron; Busteed, Philip R; Haggard, Brian E; Rossi, Colleen

    2014-01-01

    The Soil and Water Assessment Tool is widely used to predict the fate and transport of phosphorus (P) from the landscape through streams and rivers. The current in-stream P submodel may not be suitable for many stream systems, particularly those dominated by attached algae and those affected by point sources. In this research, we developed an alternative submodel based on the equilibrium P concentration concept coupled with a particulate scour and deposition model. This submodel was integrated with the SWAT model and applied to the Illinois River Watershed in Oklahoma, a basin influenced by waste water treatment plant discharges and extensive poultry litter application. The model was calibrated and validated using measured data. Highly variable in-stream P concentrations and equilibrium P concentration values were predicted spatially and temporally. The model also predicted the gradual storage of P in streambed sediments and the resuspension of this P during periodic high-flow flushing events. Waste water treatment plants were predicted to have a profound effect on P dynamics in the Illinois River due to their constant discharge even under base flow conditions. A better understanding of P dynamics in stream systems using the revised submodel may lead to the development of more effective mitigation strategies to control the impact of P from point and nonpoint sources. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  16. The impact of the structural features of the rock mass on seismicity in Polish coal mines

    Science.gov (United States)

    Patyńska, Renata

    2017-11-01

    The article presents seismic activity induced in the coal mines of the Upper Silesian Coal Basin (GZW) in relation to the locations of the occurrence of rockbursts. The comparison of these measurements with the structural features of the rock mass of coal mines indicates the possibility of estimating the so-called Unitary Energy Expenditure (UEE) in a specific time. The obtained values of UEE were compared with the distribution of seismic activity in GZW mines. The level of seismic activity in the analysed period changed and depended on the intensity of mining works and diverse mining and geological conditions. Five regions, where tremors occurred (Bytom Trough, Main Saddle, Main Trough, Kazimierz Trough, and Jejkowice and Chwałowice Trough) which belong to various structural units of the Upper Silesia were analyzed. It was found out that rock bursts were recorded only in three regions: Main Saddle, Bytom Trough, and Jejkowice and Chwałowice Trough.

  17. HRTEM and neutron diffraction study of LixMo5O17: From the ribbon (x=5) structure to the rock salt (x=12) structure

    International Nuclear Information System (INIS)

    Lebedev, O.I.; Caignaert, V.; Raveau, B.; Pop, N.; Gozzo, F.; Van Tendeloo, G.; Pralong, V.

    2011-01-01

    Structure determination of the fully intercalated phase Li 12 Mo 5 O 17 and of the deintercalated oxide Li 5 Mo 5 O 17 has been carried out by electron microscopy and neutron powder diffraction. The reversible topotactic transformation between the ordered rock salt structure of the former and the ribbon structure of the latter (closely related to that of Li 4 Mo 5 O 17 ) is explained on the following basis: both structures can be described as strips built up as an assembly of infinite ribbons of MoO 6 octahedra that are five octahedra thick, and that differ by slight displacements of the octahedral ribbons. We show that the electrochemical behavior of the Li x Mo 5 O 17 system is based on two sorts of Li + sites; those that are located within the strips between the ribbons, and those that are located at the border of the strips. The high rate of Li intercalation in this oxide and its reversibility are discussed in terms of its peculiar structure. -- Graphical abstract: Structure determination of the fully intercalated phase Li 12 Mo 5 O 17 and of the deintercalated oxide Li 5 Mo 5 O 17 has been carried out by electron microscopy and neutron powder diffraction. The reversible topotactic transformation between the ordered rock salt structure of the former and the ribbon structure of the latter is explained on the following basis: both structures can be described as strips built up as an assembly of infinite ribbons of MoO 6 octahedra that are five octahedra thick, and that differ by slight displacements of the octahedral ribbons. We show that the electrochemical behavior of the Li x Mo 5 O 17 system is based on two sorts of Li + sites; those that are located within the strips between the ribbons, and those that are located at the border of the strips. The high rate of Li intercalation in this oxide and its reversibility are discussed in terms of its peculiar structure. Research highlights: → Electron microscopy and neutron powder diffraction structure determination

  18. Predicting rock bursts in mines

    Science.gov (United States)

    Spall, H.

    1979-01-01

    In terms of lives lost, rock bursts in underground mines can be as hazardous as earthquakes on the surface. So it is not surprising that fo the last 40 years the U.S Bureau of Mines has been using seismic methods for detecting areas in underground mines where there is a high differential stress which could lead to structural instability of the rock mass being excavated.

  19. Laboratory investigations into fracture propagation characteristics of rock material

    Science.gov (United States)

    Prasad, B. N. V. Siva; Murthy, V. M. S. R.

    2018-04-01

    After Industrial Revolution, demand of materials for building up structures have increased enormously. Unfortunately, failures of such structures resulted in loss of life and property. Rock is anisotropic and discontinuous in nature with inherent flaws or so-called discontinuities in it. Rock is apparently used for construction in mining, civil, tunnelling, hydropower, geothermal and nuclear sectors [1]. Therefore, the strength of the structure built up considering rockmass as the construction material needs proper technical evaluation during designing stage itself to prevent and predict the scenarios of catastrophic failures due to these inherent fractures [2]. In this study, samples collected from nine different drilling sites have been investigated in laboratory for understanding the fracture propagation characteristics in rock. Rock material properties, ultrasonic velocities through pulse transmission technique and Mode I Fracture Toughness Testing of different variants of Dolomites and Graywackes are determined in laboratory and the resistance of the rock material to catastrophic crack extension or propagation has been determined. Based on the Fracture Toughness values and the rock properties, critical Energy Release Rates have been estimated. However further studies in this direction is to be carried out to understand the fracture propagation characteristics in three-dimensional space.

  20. Search for magnetic minerals in Martian rocks: Overview of the Rock Abrasion Tool (RAT) magnet investigation on Spirit and Opportunity

    DEFF Research Database (Denmark)

    Goetz, W.; Leer, K.; Gunnlaugsson, H.P.

    2008-01-01

    The Rock Abrasion Tool (RAT) on board the Mars Exploration Rovers (MER) is a grinding tool designed to remove dust coatings and/or weathering rinds from rocks and expose fresh rock material. Four magnets of different strengths that are built into the structure of the RAT have been attracting...... is interpreted as magnetite. The amount of abraded rock material adhering to the magnets varied strongly during the mission and is correlated in a consistent way to the amount of magnetite inferred from Mossbauer spectra for the corresponding rock. The RAT magnet experiment as performed on Opportunity also...

  1. Water - rock interaction in different rock environments

    International Nuclear Information System (INIS)

    Lamminen, S.

    1995-01-01

    The study assesses the groundwater geochemistry and geological environment of 44 study sites for radioactive waste disposal. Initially, the study sites were divided by rock type into 5 groups: (1) acid - intermediate rocks, (2) mafic - ultramafic rocks, (3) gabbros, amphibolites and gneisses that contain calc-silicate (skarn) rocks, (4) carbonates and (5) sandstones. Separate assessments are made of acid - intermediate plutonic rocks and of a subgroup that comprises migmatites, granite and mica gneiss. These all belong to the group of acid - intermediate rocks. Within the mafic -ultramafic rock group, a subgroup that comprises mafic - ultramafic plutonic rocks, serpentinites, mafic - ultramafic volcanic rocks and volcanic - sedimentary schists is also evaluated separately. Bedrock groundwaters are classified by their concentration of total dissolved solids as fresh, brackish, saline, strongly saline and brine-class groundwaters. (75 refs., 24 figs., 3 tabs.)

  2. Response spectra for nuclear structures on rock sites considering the near-fault directivity effect

    Institute of Scientific and Technical Information of China (English)

    Xu Longiun; Yang Shengchao; Xie Lili

    2010-01-01

    Near-fault ground motions, potentially with large amplitude and typical velocity pulses, may significantly impact the performance of a wide range of structures. The current study is aimed at evaluating the safety implications of the near-fault effect on nuclear power plant facilities designed according to the Chinese code. To this end, a set of near-fault ground motions at rock sites with typical forward-directivity effect is examined with special emphasis on several key parameters and response spectra. Spectral comparison of the selected records with the Chinese and other code design spectra was conducted. The bi-normalized response spectra in terms of different comer periods are utilized to derive nuclear design spectra. It is concluded that nuclear design spectra on rock sites derived from typical rupture directivity records are significantly influenced both by the earthquake magnitude and the rupture distance. The nuclear design spectra specified in the code needs to be adjusted to reflect the near-fault directivity effect of large earthquakes.

  3. Methods and uncertainty estimations of 3-D structural modelling in crystalline rocks: a case study

    Science.gov (United States)

    Schneeberger, Raphael; de La Varga, Miguel; Egli, Daniel; Berger, Alfons; Kober, Florian; Wellmann, Florian; Herwegh, Marco

    2017-09-01

    Exhumed basement rocks are often dissected by faults, the latter controlling physical parameters such as rock strength, porosity, or permeability. Knowledge on the three-dimensional (3-D) geometry of the fault pattern and its continuation with depth is therefore of paramount importance for applied geology projects (e.g. tunnelling, nuclear waste disposal) in crystalline bedrock. The central Aar massif (Central Switzerland) serves as a study area where we investigate the 3-D geometry of the Alpine fault pattern by means of both surface (fieldwork and remote sensing) and underground ground (mapping of the Grimsel Test Site) information. The fault zone pattern consists of planar steep major faults (kilometre scale) interconnected with secondary relay faults (hectometre scale). Starting with surface data, we present a workflow for structural 3-D modelling of the primary faults based on a comparison of three extrapolation approaches based on (a) field data, (b) Delaunay triangulation, and (c) a best-fitting moment of inertia analysis. The quality of these surface-data-based 3-D models is then tested with respect to the fit of the predictions with the underground appearance of faults. All three extrapolation approaches result in a close fit ( > 10 %) when compared with underground rock laboratory mapping. Subsequently, we performed a statistical interpolation based on Bayesian inference in order to validate and further constrain the uncertainty of the extrapolation approaches. This comparison indicates that fieldwork at the surface is key for accurately constraining the geometry of the fault pattern and enabling a proper extrapolation of major faults towards depth. Considerable uncertainties, however, persist with respect to smaller-sized secondary structures because of their limited spatial extensions and unknown reoccurrence intervals.

  4. Lidar-Based Rock-Fall Hazard Characterization of Cliffs

    Science.gov (United States)

    Collins, Brian D.; Greg M.Stock,

    2017-01-01

    Rock falls from cliffs and other steep slopes present numerous challenges for detailed geological characterization. In steep terrain, rock-fall source areas are both dangerous and difficult to access, severely limiting the ability to make detailed structural and volumetric measurements necessary for hazard assessment. Airborne and terrestrial lidar survey methods can provide high-resolution data needed for volumetric, structural, and deformation analyses of rock falls, potentially making these analyses straightforward and routine. However, specific methods to collect, process, and analyze lidar data of steep cliffs are needed to maximize analytical accuracy and efficiency. This paper presents observations showing how lidar data sets should be collected, filtered, registered, and georeferenced to tailor their use in rock fall characterization. Additional observations concerning surface model construction, volumetric calculations, and deformation analysis are also provided.

  5. An acoustic sensor for prediction of the structural stability of rock

    CSIR Research Space (South Africa)

    Brink, S

    2016-05-01

    Full Text Available is the entry examination procedure. Members of the entry examination team evaluate the hanging with the use of a pinch bar to both 'sound' the rock and to bar it down safely, if it is found to be dangerously loose. 'Sounding' a rock is the evaluation...

  6. The Jettencave, Southern Harz Mountains, Germany: Geophysical observations and a structural model of a shallow cave in gypsum/anhydrite-bearing rocks

    Science.gov (United States)

    Kaufmann, Georg; Romanov, Douchko

    2017-12-01

    Gypsum and anhydrite are soluble rocks, where fissures and bedding partings can be enlarged with time by the dissolution of the mineral species through water. The selective enlargement results in sub-surface voids acting as preferential flow path for the drainage of the rock. With time, larger cavities develop, and a network of cave passages can evolve. If the enlarged cave voids are not too deep under the surface, geophysical measurements can be used to detect, identify and trace these structures. We have used gravity measurements (GRAV), electrical resistivity imaging (ERI), self-potential measurements (SP), electrical conductivity measurements (EC), and ground-penetrating radar (GPR) above the cave Jettenhöhle, a cave located in the southern Harz Mountains in Germany. The Jettencave is developed in the Hauptanhydrit formation of the Permian Zechstein sequence, characterised by large breakdown rooms and an exposed water table. The overburden of the cave is only around 10-15 m, and dolomitic rocks are located in close vicinity. We present results from our geophysical surveys in vicinity of the cave. We are able to identify the cave geometry from GRAV, ERI, and GPR measurements, which distinguish the local lithology of the Permian Zechstein rocks in the area. From the ERI and EC measurements, we derive information on the void volume in the soluble rocks. We finally present a three-dimensional structural model of the Jettencave and its surroundings, based on our geophysical results and the hydrological interpretation.

  7. Hopi and Anasazi Alignments and Rock Art

    Science.gov (United States)

    Bates, Bryan C.

    The interaction of light and shadow on ancestral Puebloan rock art, or rock art demarcating sunrise/set horizon points that align with culturally significant dates, has long been assumed to be evidence of "intentional construct" for marking time or event by the native creator. However, anthropological rock art research requires the scientific control of cultural time, element orientation and placement, structure, and association with other rock art elements. The evaluation of five exemplars challenges the oft-held assumption that "if the interaction occurs, it therefore supports intentional construct" and thereby conveys meaning to the native culture.

  8. Structural analysis of porous rock reservoirs subjected to conditions of compressed air energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Friley, J.R.

    1980-01-01

    Investigations are described which were performed to assess the structural behavior of porous rock compressed air energy storage (CAES) reservoirs subjected to loading conditions of temperature and pressure felt to be typical of such an operation. Analyses performed addressed not only the nominal or mean reservoir response but also the cyclic response due to charge/discharge operation. The analyses were carried out by assuming various geometrical and material related parameters of a generic site. The objective of this study was to determine the gross response of a generic porous reservoir. The site geometry for this study assumed a cylindrical model 122 m in dia and 57 m high including thicknesses for the cap, porous, and base rock formations. The central portion of the porous zone was assumed to be at a depth of 518 m and at an initial temperature of 20/sup 0/C. Cyclic loading conditions of compressed air consisted of pressure values in the range of 4.5 to 5.2 MPa and temperature values between 143 and 204/sup 0/C.Various modes of structural behavior were studied. These response modes were analyzed using loading conditions of temperature and pressure (in the porous zone) corresponding to various operational states during the first year of simulated site operation. The results of the structural analyses performed indicate that the most severely stressed region will likely be in the wellbore vicinity and hence highly dependent on the length of and placement technique utilized in the well production length. Analyses to address this specific areas are currently being pursued.

  9. Characterization of nearfield rock - A basis for comparison of repository concepts

    International Nuclear Information System (INIS)

    Pusch, R.; Hoekmark, H.

    1991-12-01

    The hydraulic conductivity of the nearfield rock controls the rate of wetting of adjacent buffer material as well as the rate of degradation of its smectite content and of the transport of radionuclides from the buffer/rock interface. Comparison of different repository concepts with respect to the function of the nearfield rock requires a common rock structure model, which is suggested in the report. Applying this model and 2D and 3D numerical calculations for evaluation of stress-induced structural changes, major differences between the three concepts VDH, KBS3 and VLH concerning the hydraulic conductivity of the nearfield have been identified. The importance of the orientation of the excavations turns out to be particularly obvious. Further development of the rock structure model is concluded to offer ways of quantifying more accurately the damaging effects of blasting and TBM-drilling. (au)

  10. Grid-connected in-stream hydroelectric generation based on the doubly fed induction machine

    Science.gov (United States)

    Lenberg, Timothy J.

    Within the United States, there is a growing demand for new environmentally friendly power generation. This has led to a surge in wind turbine development. Unfortunately, wind is not a stable prime mover, but water is. Why not apply the advances made for wind to in-stream hydroelectric generation? One important advancement is the creation of the Doubly Fed Induction Machine (DFIM). This thesis covers the application of a gearless DFIM topology for hydrokinetic generation. After providing background, this thesis presents many of the options available for the mechanical portion of the design. A mechanical turbine is then specified. Next, a method is presented for designing a DFIM including the actual design for this application. In Chapter 4, a simulation model of the system is presented, complete with a control system that maximizes power generation based on water speed. This section then goes on to present simulation results demonstrating proper operation.

  11. Study on the Reinforcement Measures and Control Effect of the Surrounding Rock Stability Based on the Shield Tunneling Under Overpass Structure

    Directory of Open Access Journals (Sweden)

    Qian-cheng Fang

    2016-04-01

    Full Text Available To study the stability of surrounding rocks for shield tunneling under overpass structures and the safety of existing bridge structures, a practical example of the method was cited through a shield tunneling project under the overpass structure between K1+110 and K1+700 on Line 2 of Shenyang Subway, China. The sub-area reinforcement was proposed according to surrounding rock deformation characteristics during shield tunnel excavation. The bridge foundation (i.e., the clear spacing to the shield tunnel is less than 2 m was reinforced by steel support, the bridge foundation (the clear spacing is about 2~7m used “jet grouting pile” reinforcement, whereas the bridge foundation (the clear spacing is greater than 7 m did not adopt any reinforcement measures for the moment. For this study, the mean value and material heterogeneity models were established to evaluate the reinforcement effect from several aspects, such as surrounding rock deformation, plastic zone development, and safety factor. The simulation results were consistent with those of field monitoring. After reinforcement, the maximum deformation values of the surrounding rock were reduced by 4.9%, 12.2%, and 48.46%, and the maximum values of surface subsidence were decreased by 5.6%, 72.2%, and 88.64%. By contrast, the overall safety factor was increased by 4.1%, 55.46%, and 55.46%. This study posited that this reinforcement method can be adopted to solve tunnel construction problems in engineering-geological conditions effectively. References for evaluating similar projects are provided.

  12. Incoherent SSI Analysis of Reactor Building using 2007 Hard-Rock Coherency Model

    International Nuclear Information System (INIS)

    Kang, Joo-Hyung; Lee, Sang-Hoon

    2008-01-01

    Many strong earthquake recordings show the response motions at building foundations to be less intense than the corresponding free-field motions. To account for these phenomena, the concept of spatial variation, or wave incoherence was introduced. Several approaches for its application to practical analysis and design as part of soil-structure interaction (SSI) effect have been developed. However, conventional wave incoherency models didn't reflect the characteristics of earthquake data from hard-rock site, and their application to the practical nuclear structures on the hard-rock sites was not justified sufficiently. This paper is focused on the response impact of hard-rock coherency model proposed in 2007 on the incoherent SSI analysis results of nuclear power plant (NPP) structure. A typical reactor building of pressurized water reactor (PWR) type NPP is modeled classified into surface and embedded foundations. The model is also assumed to be located on medium-hard rock and hard-rock sites. The SSI analysis results are obtained and compared in case of coherent and incoherent input motions. The structural responses considering rocking and torsion effects are also investigated

  13. Modeling the effects of climate and land use change on instream temperature in the Upper Tar River, North Carolina

    Science.gov (United States)

    Daraio, J. A.; Bales, J. D.

    2011-12-01

    Freshwater mussels are among the most imperiled groups of organisms in the world. Declines in abundance and diversity in North America have been attributed to a wide range of human activities, and many species occur in habitats close to their upper thermal tolerance. We are modeling instream temperature (T) as part of an effort to understand the response of imperiled freshwater mussels to anthropogenically induced changes in water T, habitat, and flow. We used the Precipitation-Runoff Modeling System (PRMS) to model projected changes in stream discharge, and the Stream Network Temperature Model (SNTEMP) to model changes in instream T due to climate and land-use change in the Upper Tar River, North Carolina, which has a drainage area of 2200 mi^2. Down-scaled gridded 12km Global Circulation Models were used for precipitation and T inputs to PRMS simulations from the present through 2060. Land-use change through 2060 in the Upper Tar basin was estimated from SLEUTH, a model that estimates land-use change using the probability of urbanization, (results available from NC State University) and incorporated into PRMS for long term simulations. Stream segment discharge and lateral and groundwater flow into each stream segment from PRMS were used as input for SNTEMP. Groundwater T was assumed equal to the average annual air T for the basin. Lateral inflow T was estimated from physical characteristics of the basin (e.g. impervious area, cover density, cover type, solar radiation, air T) when possible, or from a regression with air T based on empirical field data at 20 sites throughout the basin. In addition to T, data on mussel and fish populations (e.g., density and species composition?) and microhabitat have been collected at these sites. The SNTEMP model was calibrated using the mean daily T at each site. Nash-Sutcliffe efficiency values ranged from 0.86 to 0.94 for mean daily T, and from 0.80 to 0.93 for maximum daily T. Ensemble simulations were run for a range of

  14. Methods and uncertainty estimations of 3-D structural modelling in crystalline rocks: a case study

    Directory of Open Access Journals (Sweden)

    R. Schneeberger

    2017-09-01

    Full Text Available Exhumed basement rocks are often dissected by faults, the latter controlling physical parameters such as rock strength, porosity, or permeability. Knowledge on the three-dimensional (3-D geometry of the fault pattern and its continuation with depth is therefore of paramount importance for applied geology projects (e.g. tunnelling, nuclear waste disposal in crystalline bedrock. The central Aar massif (Central Switzerland serves as a study area where we investigate the 3-D geometry of the Alpine fault pattern by means of both surface (fieldwork and remote sensing and underground ground (mapping of the Grimsel Test Site information. The fault zone pattern consists of planar steep major faults (kilometre scale interconnected with secondary relay faults (hectometre scale. Starting with surface data, we present a workflow for structural 3-D modelling of the primary faults based on a comparison of three extrapolation approaches based on (a field data, (b Delaunay triangulation, and (c a best-fitting moment of inertia analysis. The quality of these surface-data-based 3-D models is then tested with respect to the fit of the predictions with the underground appearance of faults. All three extrapolation approaches result in a close fit (> 10 % when compared with underground rock laboratory mapping. Subsequently, we performed a statistical interpolation based on Bayesian inference in order to validate and further constrain the uncertainty of the extrapolation approaches. This comparison indicates that fieldwork at the surface is key for accurately constraining the geometry of the fault pattern and enabling a proper extrapolation of major faults towards depth. Considerable uncertainties, however, persist with respect to smaller-sized secondary structures because of their limited spatial extensions and unknown reoccurrence intervals.

  15. Hierarchical Object-Based Mapping of Riverscape Units and in-Stream Mesohabitats Using LiDAR and VHR Imagery

    Directory of Open Access Journals (Sweden)

    Luca Demarchi

    2016-01-01

    Full Text Available In this paper, we present a new, semi-automated methodology for mapping hydromorphological indicators of rivers at a regional scale using multisource remote sensing (RS data. This novel approach is based on the integration of spectral and topographic information within a multilevel, geographic, object-based image analysis (GEOBIA. Different segmentation levels were generated based on the two sources of Remote Sensing (RS data, namely very-high spatial resolution, near-infrared imagery (VHR and high-resolution LiDAR topography. At each level, different input object features were tested with Machine Learning classifiers for mapping riverscape units and in-stream mesohabitats. The GEOBIA approach proved to be a powerful tool for analyzing the river system at different levels of detail and for coupling spectral and topographic datasets, allowing for the delineation of the natural fluvial corridor with its primary riverscape units (e.g., water channel, unvegetated sediment bars, riparian densely-vegetated units, etc. and in-stream mesohabitats with a high level of accuracy, respectively of K = 0.91 and K = 0.83. This method is flexible and can be adapted to different sources of data, with the potential to be implemented at regional scales in the future. The analyzed dataset, composed of VHR imagery and LiDAR data, is nowadays increasingly available at larger scales, notably through European Member States. At the same time, this methodology provides a tool for monitoring and characterizing the hydromorphological status of river systems continuously along the entire channel network and coherently through time, opening novel and significant perspectives to river science and management, notably for planning and targeting actions.

  16. Apparatus and method to pulverize rock using a superconducting electromagnetic linear motor

    Science.gov (United States)

    Ignatiev, Alex (Inventor)

    2009-01-01

    A rock pulverizer device based on a superconducting linear motor. The superconducting electromagnetic rock pulverizer accelerates a projectile via a superconducting linear motor and directs the projectile at high speed toward a rock structure that is to be pulverized by collision of the speeding projectile with the rock structure. The rock pulverizer is comprised of a trapped field superconducting secondary magnet mounted on a movable car following a track, a wire wound series of primary magnets mounted on the track, and the complete magnet/track system mounted on a vehicle used for movement of the pulverizer through a mine as well as for momentum transfer during launch of the rock breaking projectile.

  17. Thermal Inertia of Rocks and Rock Populations

    Science.gov (United States)

    Golombek, M. P.; Jakosky, B. M.; Mellon, M. T.

    2001-01-01

    The effective thermal inertia of rock populations on Mars and Earth is derived from a model of effective inertia versus rock diameter. Results allow a parameterization of the effective rock inertia versus rock abundance and bulk and fine component inertia. Additional information is contained in the original extended abstract.

  18. Rock Slope Monitoring from 4D Time-Lapse Structure from Motion Analysis

    Science.gov (United States)

    Kromer, Ryan; Abellan, Antonio; Chyz, Alex; Hutchinson, Jean

    2017-04-01

    Structure from Motion (SfM) photogrammetry has become an important tool for studying earth surface processes because of its flexibility, ease of use, low cost and its capability of producing high quality 3-D surface models. A major benefit of SfM is that model accuracy is fit for purpose and surveys can be designed to meet a large range of spatial and temporal scales. In the Earth sciences, research in time-lapse SfM photogrammetry or videogrammetry is an area that is difficult to undertake due to complexities in acquiring, processing and managing large 4D datasets and represents an area with significant advancement potential (Eltner et al. 2016). In this study, we investigate the potential of 4D time-lapse SfM to monitor unstable rock slopes. We tested an array of statically mounted cameras collecting time-lapse photos of a limestone rock slope located along a highway in Canada. Our setup consisted of 8 DSLR cameras with 50 mm prime lenses spaced 2-3 m apart at a distance of 10 m from the slope. The portion of the rock slope monitored was 20 m wide and 6 m high. We collected data in four phases, each having 50 photographs taken simultaneously by each camera. The first phase of photographs was taken of the stable slope. In each successive phase, we gradually moved small, discrete blocks within the rock slope by 5-15 mm, simulating pre-failure deformation of rockfall. During the last phase we also removed discrete rock blocks, simulating rockfall. We used Agisoft Photoscan's 4D processing functionality and timeline tools to create 3D point clouds from the time-lapse photographs. These tools have the benefit of attaining better accuracy photo alignments as a greater number of photos are used. For change detection, we used the 4D filtering and calibration technique proposed by Kromer et al. (2015), which takes advantage of high degrees of spatial and temporal point redundancy to decrease measurement uncertainty. Preliminary results show that it is possible to attain

  19. Developing a Virtual Rock Deformation Laboratory

    Science.gov (United States)

    Zhu, W.; Ougier-simonin, A.; Lisabeth, H. P.; Banker, J. S.

    2012-12-01

    Experimental rock physics plays an important role in advancing earthquake research. Despite its importance in geophysics, reservoir engineering, waste deposits and energy resources, most geology departments in U.S. universities don't have rock deformation facilities. A virtual deformation laboratory can serve as an efficient tool to help geology students naturally and internationally learn about rock deformation. Working with computer science engineers, we built a virtual deformation laboratory that aims at fostering user interaction to facilitate classroom and outreach teaching and learning. The virtual lab is built to center around a triaxial deformation apparatus in which laboratory measurements of mechanical and transport properties such as stress, axial and radial strains, acoustic emission activities, wave velocities, and permeability are demonstrated. A student user can create her avatar to enter the virtual lab. In the virtual lab, the avatar can browse and choose among various rock samples, determine the testing conditions (pressure, temperature, strain rate, loading paths), then operate the virtual deformation machine to observe how deformation changes physical properties of rocks. Actual experimental results on the mechanical, frictional, sonic, acoustic and transport properties of different rocks at different conditions are compiled. The data acquisition system in the virtual lab is linked to the complied experimental data. Structural and microstructural images of deformed rocks are up-loaded and linked to different deformation tests. The integration of the microstructural image and the deformation data allows the student to visualize how forces reshape the structure of the rock and change the physical properties. The virtual lab is built using the Game Engine. The geological background, outstanding questions related to the geological environment, and physical and mechanical concepts associated with the problem will be illustrated on the web portal. In

  20. GRAPHITIZATION OF METASEDIMENTARY ROCKS IN THE WESTERN KONYA

    Directory of Open Access Journals (Sweden)

    Hüseyin KURT

    2000-01-01

    Full Text Available The Paleozoic-Mesozoic metasedimentary rocks in the study area are metacarbonate, metachert, metapelite, metasandstone and metaconglomerate. Graphite layers are 1cm to 2m thick, extend laterally for tens of meters and are intercalated with metasedimentary rocks. Generally, the graphite is black in color, with a well developed cleavage which is concordant with the cleavage of the host rocks. In addition, the crystal and flake graphites formed in metasedimentary rocks are mostly aligned parallel to the cleavage planes. These metamorphic rocks are subjected to shearing and granulation providing structural control for the development of graphite. It was probably this phenomenon that first led to emphasize the relationship between graphite and metasedimentary rocks. Graphite mineralization has been controlled by bedding, microfractures and granulations. Briefly, the metamorphism has converted carbonaceous matter into graphite .

  1. 3D Printing and Digital Rock Physics for Geomaterials

    Science.gov (United States)

    Martinez, M. J.; Yoon, H.; Dewers, T. A.

    2015-12-01

    Imaging techniques for the analysis of porous structures have revolutionized our ability to quantitatively characterize geomaterials. Digital representations of rock from CT images and physics modeling based on these pore structures provide the opportunity to further advance our quantitative understanding of fluid flow, geomechanics, and geochemistry, and the emergence of coupled behaviors. Additive manufacturing, commonly known as 3D printing, has revolutionized production of custom parts with complex internal geometries. For the geosciences, recent advances in 3D printing technology may be co-opted to print reproducible porous structures derived from CT-imaging of actual rocks for experimental testing. The use of 3D printed microstructure allows us to surmount typical problems associated with sample-to-sample heterogeneity that plague rock physics testing and to test material response independent from pore-structure variability. Together, imaging, digital rocks and 3D printing potentially enables a new workflow for understanding coupled geophysical processes in a real, but well-defined setting circumventing typical issues associated with reproducibility, enabling full characterization and thus connection of physical phenomena to structure. In this talk we will discuss the possibilities that these technologies can bring to geosciences and present early experiences with coupled multiscale experimental and numerical analysis using 3D printed fractured rock specimens. In particular, we discuss the processes of selection and printing of transparent fractured specimens based on 3D reconstruction of micro-fractured rock to study fluid flow characterization and manipulation. Micro-particle image velocimetry is used to directly visualize 3D single and multiphase flow velocity in 3D fracture networks. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U

  2. In-stream Nitrogen Processing and Dilution in an Agricultural Stream Network

    Science.gov (United States)

    Prior, K.; Ward, A. S.; Davis, C. A.; Burgin, A. J.; Loecke, T.; Riveros-Iregui, D. A.; Thomas, S. A.; St Clair, M. A.

    2014-12-01

    The interaction of agricultural fertilizer use and extremes in drought and flood conditions in 2012-2013 set up conditions for a natural experiment on watershed-scale nutrient dynamics. The region-wide drought in 2012 left surface soils disconnected from stream networks and restricted nutrient use by crops, resulting in an unusually large nitrogen pool in soil columns through the winter. When wet conditions returned to the Midwest in 2013, the unused fertilizer was mobilized, resulting in a six-week period of extremely high in-stream nutrient concentrations. This study analyses three synoptic samples from the Iowa-Cedar River Basin in 2013 to quantify patterns in nitrogen dynamics. We use multiple conservative ions as tracers to estimate dilution by lateral inflows. We also estimate nutrient spiraling metrics by treating the fertilizer pulse as a constant rate nutrient addition across the watershed—a scale on which these processes are increasingly modeled numerically, but on which standard nutrient addition experiments are simply not feasible. Results of this study compare patterns in dilution and uptake across spatial and temporal scales, and bound feasible explanations for each reach of the network.

  3. Prediction of Fracture Behavior in Rock and Rock-like Materials Using Discrete Element Models

    Science.gov (United States)

    Katsaga, T.; Young, P.

    2009-05-01

    The study of fracture initiation and propagation in heterogeneous materials such as rock and rock-like materials are of principal interest in the field of rock mechanics and rock engineering. It is crucial to study and investigate failure prediction and safety measures in civil and mining structures. Our work offers a practical approach to predict fracture behaviour using discrete element models. In this approach, the microstructures of materials are presented through the combination of clusters of bonded particles with different inter-cluster particle and bond properties, and intra-cluster bond properties. The geometry of clusters is transferred from information available from thin sections, computed tomography (CT) images and other visual presentation of the modeled material using customized AutoCAD built-in dialog- based Visual Basic Application. Exact microstructures of the tested sample, including fractures, faults, inclusions and void spaces can be duplicated in the discrete element models. Although the microstructural fabrics of rocks and rock-like structures may have different scale, fracture formation and propagation through these materials are alike and will follow similar mechanics. Synthetic material provides an excellent condition for validating the modelling approaches, as fracture behaviours are known with the well-defined composite's properties. Calibration of the macro-properties of matrix material and inclusions (aggregates), were followed with the overall mechanical material responses calibration by adjusting the interfacial properties. The discrete element model predicted similar fracture propagation features and path as that of the real sample material. The path of the fractures and matrix-inclusion interaction was compared using computed tomography images. Initiation and fracture formation in the model and real material were compared using Acoustic Emission data. Analysing the temporal and spatial evolution of AE events, collected during the

  4. Gas migration in argillaceous rock

    International Nuclear Information System (INIS)

    Alonso, E. E.; Olivella, S.

    2007-01-01

    The intrinsic gas permeability of fractured argillaceous rocks depends on the current structure of micro-cracks and fissures of the rock. They are a consequence of the initial state and the subsequent deformations induced by stress and gas pressure changes. Stresses are also coupled with fluid pressures and, therefore, gas flow and mechanical behaviour are intensely coupled. Laboratory experiments, aimed at determining intrinsic permeability, show the relevant effect of volumetric deformations induced by isotropic, as well as deviatoric stress changes. The relevance, in practice, of the flow-mechanical coupling is illustrated by means of some results obtained during the performance of the drift scale test (DST) in fractured tuff in the Yucca Mountain facility. The technique of embedding discontinuities in continuum thermo-hydro-mechanical elements is capable of reproducing observed features of gas flow migration in clayey rocks. An example is described. It is believed that the developed approach provides a powerful computational procedure to handle complex gas phenomena in clayey rocks. (author)

  5. Testing and modeling of cyclically loaded rock anchors

    Directory of Open Access Journals (Sweden)

    Joar Tistel

    2017-12-01

    Full Text Available The Norwegian Public Roads Administration (NPRA is planning for an upgrade of the E39 highway route at the westcoast of Norway. Fixed links shall replace ferries at seven fjord crossings. Wide spans and large depths at the crossings combined with challenging subsea topography and environmental loads call for an extension of existing practice. A variety of bridge concepts are evaluated in the feasibility study. The structures will experience significant loads from deadweight, traffic and environment. Anchoring of these forces is thus one of the challenges met in the project. Large-size subsea rock anchors are considered a viable alternative. These can be used for anchoring of floating structures but also with the purpose of increasing capacity of fixed structures. This paper presents first a thorough study of factors affecting rock anchor bond capacity. Laboratory testing of rock anchors subjected to cyclic loading is thereafter presented. Finally, the paper presents a model predicting the capacity of a rock anchor segment, in terms of a ribbed bar, subjected to a cyclic load history. The research assumes a failure mode occurring in the interface between the rock anchor and the surrounding grout. The constitutive behavior of the bonding interface is investigated for anchors subjected to cyclic one-way tensile loads. The model utilizes the static bond capacity curve as a basis, defining the ultimate bond τbu and the slip s1 at τbu. A limited number of input parameters are required to apply the model. The model defines the bond-slip behavior with the belonging rock anchor capacity depending on the cyclic load level (τmax cy/τbu, the cyclic load ratio (R = τmin cy/τmax cy, and the number of load cycles (N. The constitutive model is intended to model short anchor lengths representing an incremental length of a complete rock anchor.

  6. Development of evaluation methods for impact of earthquake-induced slope failure on nearby critical structures. Analysis of behavior of collapsed rock masses using 3-D distinct element method

    International Nuclear Information System (INIS)

    Ishimaru, Makoto; Tochigi, Hitoshi; Nakajima, Masato; Shirai, Koji

    2012-01-01

    Recently, importance of evaluation for impact of earthquake-induced slope failure on nearby critical structures is increasing in order to evaluate seismic stability of the slope, in addition to evaluating the possibilities of slope failure. In this study, we presented an examination flow chart to evaluate the impact on structures after slope failure. In the examination flow chart, we assumed the following four considerations; (1) evaluation of the collapse region of the slope, (2) evaluation of behavior of the collapsed rock masses, (3) evaluation of the impact on the structures, (4) examination of the countermeasures. And, for the purpose of using three dimensional distinct element method (DEM) for evaluation of behavior of the collapsed rock masses, we firstly confirmed applicability of DEM to behavior of a mass hurtling down the slope by means of comparing with the model test results. Moreover, we clarified influence of initial position or restitution coefficient of rock masses on final traveling distance of collapsed rock masses. (author)

  7. Continuation of down-hole geophysical testing for rock sockets : [technical summary].

    Science.gov (United States)

    2013-11-01

    The rock socket is critical to a drilled shaft : foundation because it lies within a rock stratum : and accounts for much of the capacity of the : foundational unit. Consistency of the rocks : structure and composition must be identifed : because ...

  8. Rock pushing and sampling under rocks on Mars

    Science.gov (United States)

    Moore, H.J.; Liebes, S.; Crouch, D.S.; Clark, L.V.

    1978-01-01

    Viking Lander 2 acquired samples on Mars from beneath two rocks, where living organisms and organic molecules would be protected from ultraviolet radiation. Selection of rocks to be moved was based on scientific and engineering considerations, including rock size, rock shape, burial depth, and location in a sample field. Rock locations and topography were established using the computerized interactive video-stereophotogrammetric system and plotted on vertical profiles and in plan view. Sampler commands were developed and tested on Earth using a full-size lander and surface mock-up. The use of power by the sampler motor correlates with rock movements, which were by plowing, skidding, and rolling. Provenance of the samples was determined by measurements and interpretation of pictures and positions of the sampler arm. Analytical results demonstrate that the samples were, in fact, from beneath the rocks. Results from the Gas Chromatograph-Mass Spectrometer of the Molecular Analysis experiment and the Gas Exchange instrument of the Biology experiment indicate that more adsorbed(?) water occurs in samples under rocks than in samples exposed to the sun. This is consistent with terrestrial arid environments, where more moisture occurs in near-surface soil un- der rocks than in surrounding soil because the net heat flow is toward the soil beneath the rock and the rock cap inhibits evaporation. Inorganic analyses show that samples of soil from under the rocks have significantly less iron than soil exposed to the sun. The scientific significance of analyses of samples under the rocks is only partly evaluated, but some facts are clear. Detectable quantities of martian organic molecules were not found in the sample from under a rock by the Molecular Analysis experiment. The Biology experiments did not find definitive evidence for Earth-like living organisms in their sample. Significant amounts of adsorbed water may be present in the martian regolith. The response of the soil

  9. Theoretical study of rock mass investigation efficiency

    International Nuclear Information System (INIS)

    Holmen, Johan G.; Outters, Nils

    2002-05-01

    The study concerns a mathematical modelling of a fractured rock mass and its investigations by use of theoretical boreholes and rock surfaces, with the purpose of analysing the efficiency (precision) of such investigations and determine the amount of investigations necessary to obtain reliable estimations of the structural-geological parameters of the studied rock mass. The study is not about estimating suitable sample sizes to be used in site investigations.The purpose of the study is to analyse the amount of information necessary for deriving estimates of the geological parameters studied, within defined confidence intervals and confidence level In other words, how the confidence in models of the rock mass (considering a selected number of parameters) will change with amount of information collected form boreholes and surfaces. The study is limited to a selected number of geometrical structural-geological parameters: Fracture orientation: mean direction and dispersion (Fisher Kappa and SRI). Different measures of fracture density (P10, P21 and P32). Fracture trace-length and strike distributions as seen on horizontal windows. A numerical Discrete Fracture Network (DFN) was used for representation of a fractured rock mass. The DFN-model was primarily based on the properties of an actual fracture network investigated at the Aespoe Hard Rock Laboratory. The rock mass studied (DFN-model) contained three different fracture sets with different orientations and fracture densities. The rock unit studied was statistically homogeneous. The study includes a limited sensitivity analysis of the properties of the DFN-model. The study is a theoretical and computer-based comparison between samples of fracture properties of a theoretical rock unit and the known true properties of the same unit. The samples are derived from numerically generated boreholes and surfaces that intersect the DFN-network. Two different boreholes are analysed; a vertical borehole and a borehole that is

  10. Forced vibration tests of a model foundation on rock ground

    International Nuclear Information System (INIS)

    Kisaki, N.; Siota, M.; Yamada, M.; Ikeda, A.; Tsuchiya, H.; Kitazawa, K.; Kuwabara, Y.; Ogiwara, Y.

    1983-01-01

    The response of very stiff structures, such as nuclear reactor buildings, to earthquake ground motion is significantly affected by radiation damping due to the soil-structure interaction. The radiation damping can be computed by vibration admittance theory or dynamical ground compliance theory. In order to apply the values derived from these theories to the practical problems, comparative studies between theoretical results and experimental results concerning the soil-structure interaction, especially if the ground is rock, are urgently needed. However, experimental results for rock are less easily obtained than theoretical ones. The purpose of this paper is to describe the harmonic excitation tests of a model foundation on rock and to describe the results of comparative studies. (orig./HP)

  11. Poisson's Ratio and Auxetic Properties of Natural Rocks

    Science.gov (United States)

    Ji, Shaocheng; Li, Le; Motra, Hem Bahadur; Wuttke, Frank; Sun, Shengsi; Michibayashi, Katsuyoshi; Salisbury, Matthew H.

    2018-02-01

    Here we provide an appraisal of the Poisson's ratios (υ) for natural elements, common oxides, silicate minerals, and rocks with the purpose of searching for naturally auxetic materials. The Poisson's ratios of equivalently isotropic polycrystalline aggregates were calculated from dynamically measured elastic properties. Alpha-cristobalite is currently the only known naturally occurring mineral that has exclusively negative υ values at 20-1,500°C. Quartz and potentially berlinite (AlPO4) display auxetic behavior in the vicinity of their α-β structure transition. None of the crystalline igneous and metamorphic rocks (e.g., amphibolite, gabbro, granite, peridotite, and schist) display auxetic behavior at pressures of >5 MPa and room temperature. Our experimental measurements showed that quartz-rich sedimentary rocks (i.e., sandstone and siltstone) are most likely to be the only rocks with negative Poisson's ratios at low confining pressures (≤200 MPa) because their main constituent mineral, α-quartz, already has extremely low Poisson's ratio (υ = 0.08) and they contain microcracks, micropores, and secondary minerals. This finding may provide a new explanation for formation of dome-and-basin structures in quartz-rich sedimentary rocks in response to a horizontal compressional stress in the upper crust.

  12. A Comparison of underground opening support design methods in jointed rock mass

    International Nuclear Information System (INIS)

    Gharavi, M.; Shafiezadeh, N.

    2008-01-01

    It is of great importance to consider long-term stability of rock mass around the openings of underground structure. during design, construction and operation of the said structures in rock. In this context. three methods namely. empirical. analytical and numerical have been applied to design and analyze the stability of underground infrastructure at the Siah Bisheh Pumping Storage Hydro-Electric Power Project in Iran. The geological and geotechnical data utilized in this article were selected and based on the preliminary studies of this project. In the initial stages of design. it was recommended that, two methods of rock mass classification Q and rock mass rating should be utilized for the support system of the underground cavern. Next, based on the structural instability, the support system was adjusted by the analytical method. The performance of the recommended support system was reviewed by the comparison of the ground response curve and rock support interactions with surrounding rock mass, using FEST03 software. Moreover, for further assessment of the realistic rock mass behavior and support system, the numerical modeling was performed utilizing FEST03 software. Finally both the analytical and numerical methods were compared, to obtain satisfactory results complimenting each other

  13. Variation in flow and suspended sediment transport in a montane river affected by hydropeaking and instream mining

    Science.gov (United States)

    Béjar, M.; Vericat, D.; Batalla, R. J.; Gibbins, C. N.

    2018-06-01

    The temporal and spatial variability of water and sediment loads of rivers is controlled by a suite of factors whose individual effects are often difficult to disentangle. While land use changes and localised human activities such as instream mining and hydropeaking alter water and sediment transfer, tributaries naturally contribute to discharge and sediment load of mainstem rivers, and so may help compensate upstream anthropogenic factors. The work presented here aimed to assess water and the sediment transfer in a river reach affected by gravel extraction and hydropeaking, set against a backdrop of changes to the supply of water and sediment from tributaries. Discharge and suspended sediment transport were monitored during two average hydrological years at three cross-sections along a 10-km reach of the upper River Cinca, in the Southern Pyrenees. Water and sediment loads differed substantially between the reaches. The upper reach showed a largely torrential discharge regime, controlled mainly by floods, and had high but variable water and sediment loads. The middle reach was influenced markedly by hydropeaking and tributary inflows, which increased its annual water yield four-fold. Suspended sediment load in this reach increased by only 25% compared to upstream, indicating that dilution predominated. In the lowermost section, while discharge remained largely unaltered, sediment load increased appreciably as a result of changes to sediment availability from instream mining and inputs from tributaries. At the reach scale, snowmelt and summer and autumn thunderstorms were responsible for most of the water yield, while flood flows determined the magnitude and transport of the sediment load. The study highlights that a combination of natural and human factors control the spatial and temporal transfer of water and sediment in river channels and that, depending on their geographic location and effect-size, can result in marked variability even over short downstream

  14. The selectivity and promiscuity of brain-neuroregenerative inhibitors between ROCK1 and ROCK2 isoforms: An integration of SB-QSSR modelling, QM/MM analysis and in vitro kinase assay.

    Science.gov (United States)

    Zhu, L; Yang, Y; Lu, X

    2016-01-01

    The Rho-associated kinases (ROCKs) have long been recognized as an attractive therapeutic target for various neurological diseases; selective inhibition of ROCK1 and ROCK2 isoforms would result in distinct biological effects on neurogenesis, neuroplasticity and neuroregeneration after brain surgery and traumatic brain injury. However, the discovery and design of isoform-selective inhibitors remain a great challenge due to the high conservation and similarity between the kinase domains of ROCK1 and ROCK2. Here, a structure-based quantitative structure-selectivity relationship (SB-QSSR) approach was used to correlate experimentally measured selectivity with the difference in inhibitor binding to the two kinase isoforms. The resulting regression models were examined rigorously through both internal cross-validation and external blind validation; a nonlinear predictor was found to have high fitting stability and strong generalization ability, which was then employed to perform virtual screening against a structurally diverse, drug-like compound library. Consequently, five and seven hits were identified as promising candidates of 1-o-2 and 2-o-1 selective inhibitors, respectively, from which seven purchasable compounds were tested in vitro using a standard kinase assay protocol to determine their inhibitory activity against and selectivity between ROCK1 and ROCK2. The structural basis, energetic property and biological implication underlying inhibitor selectivity and promiscuity were also investigated systematically using a hybrid quantum mechanics/molecular mechanics (QM/MM) scheme.

  15. Structural elements and incremental strain history of the basement rocks of Um Had area, central Eastern Desert, Egypt

    International Nuclear Information System (INIS)

    Akawy, Ahmed

    2009-01-01

    The Um Had area, central Eastern Desert, Egypt shows a regional stretching in the NW-SE and a contraction in the NE-SW direction. Major NW-SE folds, small recumbent folds, and local thrusts and reverse faults were recognized. Complicated relation between folds and boudinage was identified. This stretching amount ranges from 1.282 to 1.309. Earlier coaxial and later non-coaxial strains were inferred. The change from axial to non-coaxial stress regime was gradual and the latter was associated with minor clockwise and anticlockwise rotation of structural elements. During the non-coaxial strain, strain fringes were formed as a consequence of the high circulation of fluids in low temperature and high pressure conditions. Superimposed strain fringes indicating right- and left-lateral senses of movement were recognized. At least three generations of fringes were recognized, implying three stages of non-coaxial stretching. Each generation has about 15 increments which show irregular strain gradient and intensity over the different increments. Eastwards, the strain increments became mature and westwards, the finite strain increases. The strongest finite strain was found in a narrow belt delimiting the basement rocks on the west and underlying the Phanerozoic sediments. Chocolate-tablet structure was recorded and indicates later multidirectional tension. Not all Nubia Sandstone exposures are overlying the basement rocks and some are separated by NW-SE normal faults. Major NW-SE normal faults are cutting basement rocks of different ages. (author)

  16. Structural observations and U-Pb mineral ages from igneous rocks at the Archaean-Palaeoproterozoic boundary in the Salahmi Schist Belt, central Finland: constraints on tectonic evolution

    Directory of Open Access Journals (Sweden)

    Pietikäinen, K.

    1999-06-01

    Full Text Available The study area in Vieremä, central Finland, contains part of Archaean-Palaeoproterozoic boundary. In the east, the area comprises Archaean gneiss and the Salahmi Schist Belt. The rocks of the schist belt are turbiditic metagreywackes, with well-preserved depositional structures, occurring as Proterozoic wedge-shaped blocks, and staurolite schists, the latter representing higher-strained and metamorphosed equivalents of the metagreywackes. In the west of the area there is an Archaean gneiss block, containing strongly elongated structures, and deformed Svecofennian supracrustal rocks, which are cut by deformed granitoids. These are juxtaposed with the schist belt. The boundaries of these tectonometamorphic blocks are narrow, highly strained mylonites and thrust zones. The metamorphic grade of the supracrustal rocks increases from east to west, the increase being stepwise across the mylonitic block boundaries. The rocks are more deformed from east to west with younger structures overprinting. In the staurolite schists of the Salahmi Schist Belt, the most prominent structure is a lineation (L2 that overprints the bedding and axial plane foliation. In Sorronmäki quarry, at the western boundary of the schist belt, this Palaeoproterozoic lineation dominates all the structures in tonalite gneiss, which gives a U-Pb age of 2731±6 Ma. Southeast of the quarry, at the same boundary, the Salahmi schists have been overturned towards the northeast, suggesting that the Archaean gneiss at Sorronmäki has been thrust towards the northeast over these rocks. In the western part of the study area, the Leppikangas granodiorite that intrudes the Svecofennian supracrustal rocks gives a U-Pb age of 1891+6 Ma. In the granodiorite, a strong lineation formed by the intersection of two foliations, which maybe L2 is associated with thrusting towards the northeast. The monazite age of the Archaean Sorronmäki gneiss is 1817+3 Ma, and the titanite age of the Svecofennian

  17. Structural analysis of cataclastic rock of active fault damage zones: An example from Nojima and Arima-Takatsuki fault zones (SW Japan)

    Science.gov (United States)

    Satsukawa, T.; Lin, A.

    2016-12-01

    Most of the large intraplate earthquakes which occur as slip on mature active faults induce serious damages, in spite of their relatively small magnitudes comparing to subduction-zone earthquakes. After 1995 Kobe Mw7.2 earthquake, a number of studies have been done to understand the structure, physical properties and dynamic phenomenon of active faults. However, the deformation mechanics and related earthquake generating mechanism in the intraplate active fault zone are still poorly understood. The detailed, multi-scalar structural analysis of faults and of fault rocks has to be the starting point for reconstructing the complex framework of brittle deformation. Here, we present two examples of active fault damage zones: Nojima fault and Arima-Takatsuki active fault zone in the southwest Japan. We perform field investigations, combined with meso-and micro-structural analyses of fault-related rocks, which provide the important information in reconstructing the long-term seismic faulting behavior and tectonic environment. Our study shows that in both sites, damage zone is observed in over 10m, which is composed by the host rocks, foliated and non-foliated cataclasites, fault gouge and fault breccia. The slickenside striations in Asano fault, the splay fault of Nojima fault, indicate a dextral movement sense with some normal components. Whereas, those of Arima-Takatsuki active fault shows a dextral strike-slip fault with minor vertical component. Fault gouges consist of brown-gray matrix of fine grains and composed by several layers from few millimeters to a few decimeters. It implies that slip is repeated during millions of years, as the high concentration and physical interconnectivity of fine-grained minerals in brittle fault rocks produce the fault's intrinsic weakness in the crust. Therefore, faults rarely express only on single, discrete deformation episode, but are the cumulative result of several superimposed slip events.

  18. Microscopic study of rock for estimating long-term behavior

    International Nuclear Information System (INIS)

    Ichikawa, Yasuaki

    1997-03-01

    One must consider micro-structures of rock and rock mass in order to predict the long-term behavior for more than ten thousand years. First we observe the micro-crack distribution of granite which is commonly distributed in Japan, and is widely used for several structures. The creep under constant load and the relaxation under constant displacement are typical time dependent phenomena, and we performed a series of relaxation tests under microscope observation in laboratory. The specimen that is preserved in water is granite as mentioned above. The aim of this experiment is to observe the sequential propagation of micro-cracks and its affect to the macroscopic response of the rock material under relaxation state. Next, a viscoelastic homogenization method is applied for analyzing the behavior of granite that is composed of several kinds of minerals (i.e., a polycrystalline material). The homogenization method developed for analyzing mechanics of composite materials is a mathematical theory that can describe the macroscopic behavior accounting for the microscopic characteristics with periodic microstructures. In this study, it is applied to a polycrystalline rock which involves a few minerals and micro-cracks. Furthermore, it is required to apply the homogenization analysis for rock materials which show a nonlinear time dependent behavior, so we develop a new elasto-visco-plastic homogenization theory, and its validity is checked for some ground structures made by clay. (author)

  19. Estimating the Wet-Rock P-Wave Velocity from the Dry-Rock P-Wave Velocity for Pyroclastic Rocks

    Science.gov (United States)

    Kahraman, Sair; Fener, Mustafa; Kilic, Cumhur Ozcan

    2017-07-01

    Seismic methods are widely used for the geotechnical investigations in volcanic areas or for the determination of the engineering properties of pyroclastic rocks in laboratory. Therefore, developing a relation between the wet- and dry-rock P-wave velocities will be helpful for engineers when evaluating the formation characteristics of pyroclastic rocks. To investigate the predictability of the wet-rock P-wave velocity from the dry-rock P-wave velocity for pyroclastic rocks P-wave velocity measurements were conducted on 27 different pyroclastic rocks. In addition, dry-rock S-wave velocity measurements were conducted. The test results were modeled using Gassmann's and Wood's theories and it was seen that estimates for saturated P-wave velocity from the theories fit well measured data. For samples having values of less and greater than 20%, practical equations were derived for reliably estimating wet-rock P-wave velocity as function of dry-rock P-wave velocity.

  20. Rock encrusting assemblages: Structure and distribution along the Baltic Sea

    Science.gov (United States)

    Grabowska, Monika; Grzelak, Katarzyna; Kukliński, Piotr

    2015-09-01

    Aquatic community structure and dynamics are generally controlled by a variety of biological and physical factors. Among these factors in marine ecosystems, salinity is known to have a significant effect on species occurrence and composition. In this study, we investigated the large-scale distribution and abundance of encrusting fauna along a salinity gradient on the shallow Baltic Sea rocky coast. Rock samples collected from 14 locations distributed between the Gulf of Bothnia (salinity 0.6) and Skagerrak (salinity 28) supported a total number of 24 encrusting species. The faunas were composed mostly of marine species with opportunistic life histories; however, some brackish water specialists were also present. The number of species and abundance counts is strongly positively correlated with increases in salinity. No encrusting faunas were recorded below salinity level 4. Multivariate analysis (nMDS) revealed three major groups based on species composition that differed in terms of abundance and number of species. Each group was associated with specific salinity conditions. The first assemblage type occurred within salinity 4-7, the second within salinity between 22 and 27, and the third type was a mixture between the two observed at a salinity of approximately 17. This study indicates that to determine the assemblage structure of the Baltic Sea encrusting fauna, analyses at the family level were found to be a reliable surrogate for species composition.

  1. The Impact of Host Rock Geochemistry on Bacterial Community Structure in Oligotrophic Cave Environments.

    Directory of Open Access Journals (Sweden)

    Hazel A. Barton

    2007-07-01

    Full Text Available Despite extremely starved conditions, caves contain surprisingly diverse microbial communities. Our research is geared toward understanding what ecosystems drivers are responsible for this high diversity. To asses the effect of rock fabric and mineralogy, we carried out a comparative geomicrobiology study within Carlsbad Cavern, New Mexico, USA. Samples were collected from two different geologic locations within the cave: WF1 in the Massive Member of the Capitan Formation and sF88 in the calcareous siltstones of the Yates Formation. We examined the organic content at each location using liquid chromatography mass spectroscopy and analyzed microbial community structure using molecular phylogenetic analyses. In order to assess whether microbial activity was leading to changes in the bedrock at each location, the samples were also examined by petrology, X-ray diffraction (XRD and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX. Our results suggest that on the chemically complex Yates Formation (sF88, the microbial community was significantly more diverse than on the limestone surfaces of the Capitan (WF1, despite a higher total number of cells on the latter. Further, the broader diversity of bacterial species at sF88 reflected a larger range of potential metabolic capabilities, presumably due to opportunities to use ions within the rock as nutrients and for chemolithotrophic energy production. The use of these ions at sF88 is supported by the formation of a corrosion residue, presumably through microbial scavenging activities. Our results suggest that rock fabric and mineralogy may be an important driver of ecosystem function and should be carefully reviewed when carrying out microbial community analysis in cave environments.

  2. 'Escher' Rock

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Chemical Changes in 'Endurance' Rocks [figure removed for brevity, see original site] Figure 1 This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock dubbed 'Escher' on the southwestern slopes of 'Endurance Crater.' Scientists believe the rock's fractures, which divide the surface into polygons, may have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Opportunity has spent the last 14 sols investigating Escher, specifically the target dubbed 'Kirchner,' and other similar rocks with its scientific instruments. This image was taken on sol 208 (Aug. 24, 2004) by the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters. The graph above shows that rocks located deeper into 'Endurance Crater' are chemically altered to a greater degree than rocks located higher up. This chemical alteration is believed to result from exposure to water. Specifically, the graph compares ratios of chemicals between the deep rock dubbed 'Escher,' and the more shallow rock called 'Virginia,' before (red and blue lines) and after (green line) the Mars Exploration Rover Opportunity drilled into the rocks. As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend. These data were taken by the rover's alpha particle X-ray spectrometer.

  3. Quantitative rock-fall hazard and risk assessment for Yosemite Valley, Yosemite National Park, California

    Science.gov (United States)

    Stock, Greg M.; Luco, Nicolas; Collins, Brian D.; Harp, Edwin L.; Reichenbach, Paola; Frankel, Kurt L.

    2014-01-01

    Rock falls are common in Yosemite Valley, California, posing substantial hazard and risk to the approximately four million annual visitors to Yosemite National Park. Rock falls in Yosemite Valley over the past few decades have damaged structures and caused injuries within developed regions located on or adjacent to talus slopes highlighting the need for additional investigations into rock-fall hazard and risk. This assessment builds upon previous investigations of rock-fall hazard and risk in Yosemite Valley and focuses on hazard and risk to structures posed by relatively frequent fragmental-type rock falls as large as approximately 100,000 (cubic meters) in volume.

  4. Recent advances in analysis and prediction of Rock Falls, Rock Slides, and Rock Avalanches using 3D point clouds

    Science.gov (United States)

    Abellan, A.; Carrea, D.; Jaboyedoff, M.; Riquelme, A.; Tomas, R.; Royan, M. J.; Vilaplana, J. M.; Gauvin, N.

    2014-12-01

    The acquisition of dense terrain information using well-established 3D techniques (e.g. LiDAR, photogrammetry) and the use of new mobile platforms (e.g. Unmanned Aerial Vehicles) together with the increasingly efficient post-processing workflows for image treatment (e.g. Structure From Motion) are opening up new possibilities for analysing, modeling and predicting rock slope failures. Examples of applications at different scales ranging from the monitoring of small changes at unprecedented level of detail (e.g. sub millimeter-scale deformation under lab-scale conditions) to the detection of slope deformation at regional scale. In this communication we will show the main accomplishments of the Swiss National Foundation project "Characterizing and analysing 3D temporal slope evolution" carried out at Risk Analysis group (Univ. of Lausanne) in close collaboration with the RISKNAT and INTERES groups (Univ. of Barcelona and Univ. of Alicante, respectively). We have recently developed a series of innovative approaches for rock slope analysis using 3D point clouds, some examples include: the development of semi-automatic methodologies for the identification and extraction of rock-slope features such as discontinuities, type of material, rockfalls occurrence and deformation. Moreover, we have been improving our knowledge in progressive rupture characterization thanks to several algorithms, some examples include the computing of 3D deformation, the use of filtering techniques on permanently based TLS, the use of rock slope failure analogies at different scales (laboratory simulations, monitoring at glacier's front, etc.), the modelling of the influence of external forces such as precipitation on the acceleration of the deformation rate, etc. We have also been interested on the analysis of rock slope deformation prior to the occurrence of fragmental rockfalls and the interaction of this deformation with the spatial location of future events. In spite of these recent advances

  5. Simulation of rock deformation behavior

    Directory of Open Access Journals (Sweden)

    Я. И. Рудаев

    2016-12-01

    Full Text Available A task of simulating the deformation behavior of geomaterials under compression with account of over-extreme branch has been addressed. The physical nature of rock properties variability as initially inhomogeneous material is explained by superposition of deformation and structural transformations of evolutionary type within open nonequilibrium systems. Due to this the description of deformation and failure of rock is related to hierarchy of instabilities within the system being far from thermodynamic equilibrium. It is generally recognized, that the energy function of the current stress-strain state is a superposition of potential component and disturbance, which includes the imperfection parameter accounting for defects not only existing in the initial state, but also appearing under load. The equation of state has been obtained by minimizing the energy function by the order parameter. The imperfection parameter is expressed through the strength deterioration, which is viewed as the internal parameter of state. The evolution of strength deterioration has been studied with the help of Fokker – Planck equation, which steady form corresponds to rock statical stressing. Here the diffusion coefficient is assumed to be constant, while the function reflecting internal sliding and loosening of the geomaterials is assumed as an antigradient of elementary integration catastrophe. Thus the equation of state is supplemented with a correlation establishing relationship between parameters of imperfection and strength deterioration. While deformation process is identified with the change of dissipative media, coupled with irreversible structural fluctuations. Theoretical studies are proven with experimental data obtained by subjecting certain rock specimens to compression.

  6. High concentration suspended sediment measurments using acontinuous fiber optic in-stream transmissometer

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Chris G.; Laycak, Danny T.; Hoppes, William; Tran,Nguyen T.; Shi, Frank G.

    2004-05-26

    Suspended sediment loads mobilized during high flow periods in rivers and streams are largely uncharacterized. In smaller and intermittent streams, a large storm may transport a majority of the annual sediment budget. Therefore monitoring techniques that can measure high suspended sediment concentrations at semi-continuous time intervals are needed. A Fiber optic In-stream Transmissometer (FIT) is presented for continuous measurement of high concentration suspended sediment in storm runoff. FIT performance and precision were demonstrated to be reasonably good for suspended sediment concentrations up to 10g/L. The FIT was compared to two commercially available turbidity devices and provided better precision and accuracy at both high and low concentrations. Both turbidity devices were unable to collect measurements at concentrations greater than 4 g/L. The FIT and turbidity measurements were sensitive to sediment particle size. Particle size dependence of transmittance and turbidity measurement poses the greatest problem for calibration to suspended sediment concentration. While the FIT was demonstrated to provide acceptable measurements of high suspended sediment concentrations, approaches to real-time suspended sediment detection need to address the particle size dependence in concentration measurements.

  7. Geomechanical analysis of excavation-induced rock mass behavior of faulted Opalinus clay at the Mont Terri underground rock laboratory (Switzerland)

    International Nuclear Information System (INIS)

    Thoeny, R.

    2014-01-01

    Clay rock formations are potential host rocks for deep geological disposal of nuclear waste. However, they exhibit relatively low strength and brittle failure behaviour. Construction of underground openings in clay rocks may lead to the formation of an excavation damage zone (EDZ) in the near-field area of the tunnel. This has to be taken into account during risk assessment for waste-disposal facilities. To investigate the geomechanical processes associated with the rock mass response of faulted Opalinus Clay during tunnelling, a full-scale ‘mine-by’ experiment was carried out at the Mont Terri Underground Rock Laboratory (URL) in Switzerland. In the ‘mine-by’ experiment, fracture network characteristics within the experimental section were characterized prior to and after excavation by integrating structural data from geological mapping of the excavation surfaces and from four pre- and post-excavation boreholes.The displacements and deformations in the surrounding rock mass were measured using geo-technical instrumentation including borehole inclinometers, extensometers and deflectometers, together with high-resolution geodetic displacement measurements and laser scanning measurements on the excavation surfaces. Complementary data was gathered from structural and geophysical characterization of the surrounding rock mass. Geological and geophysical techniques were used to analyse the structural and kinematic relationships between the natural and excavation-induced fracture network surrounding the ‘mine-by’ experiment. Integrating the results from seismic refraction tomography, borehole logging, and tunnel surface mapping revealed that spatial variations in fault frequency along the tunnel axis alter the rock mass deformability and strength. Failure mechanisms, orientation and frequency of excavation-induced fractures are significantly influenced by tectonic faults. On the side walls, extensional fracturing tangential to the tunnel circumference was the

  8. Geomechanical analysis of excavation-induced rock mass behavior of faulted Opalinus clay at the Mont Terri underground rock laboratory (Switzerland)

    Energy Technology Data Exchange (ETDEWEB)

    Thoeny, R.

    2014-07-01

    Clay rock formations are potential host rocks for deep geological disposal of nuclear waste. However, they exhibit relatively low strength and brittle failure behaviour. Construction of underground openings in clay rocks may lead to the formation of an excavation damage zone (EDZ) in the near-field area of the tunnel. This has to be taken into account during risk assessment for waste-disposal facilities. To investigate the geomechanical processes associated with the rock mass response of faulted Opalinus Clay during tunnelling, a full-scale ‘mine-by’ experiment was carried out at the Mont Terri Underground Rock Laboratory (URL) in Switzerland. In the ‘mine-by’ experiment, fracture network characteristics within the experimental section were characterized prior to and after excavation by integrating structural data from geological mapping of the excavation surfaces and from four pre- and post-excavation boreholes.The displacements and deformations in the surrounding rock mass were measured using geo-technical instrumentation including borehole inclinometers, extensometers and deflectometers, together with high-resolution geodetic displacement measurements and laser scanning measurements on the excavation surfaces. Complementary data was gathered from structural and geophysical characterization of the surrounding rock mass. Geological and geophysical techniques were used to analyse the structural and kinematic relationships between the natural and excavation-induced fracture network surrounding the ‘mine-by’ experiment. Integrating the results from seismic refraction tomography, borehole logging, and tunnel surface mapping revealed that spatial variations in fault frequency along the tunnel axis alter the rock mass deformability and strength. Failure mechanisms, orientation and frequency of excavation-induced fractures are significantly influenced by tectonic faults. On the side walls, extensional fracturing tangential to the tunnel circumference was the

  9. Influence of structural parameter included in nonlocal rock mass model on stress concentration around circular tunnel

    Science.gov (United States)

    Lavrikov, SV; Mikenina, OA; Revuzhenko, AF

    2018-03-01

    A model of elastic body, including local curvature of elementary volume, is matched with a nonlocal model with a linear structural parameter in the differential approximation. The problem on deformation of rock mass around a circular cross section tunnel is solved numerically. The contours of the calculated stresses are plotted. It is shown that inclusion of local bends in the model results in expansion of influence zone of the tunnel and reduces stress concentration factor at the tunnel boundary.

  10. Use of overburden rocks from open-pit coal mines and waste coals of Western Siberia for ceramic brick production with a defect-free structure

    Science.gov (United States)

    Stolboushkin, A. Yu; Ivanov, A. I.; Storozhenko, G. I.; Syromyasov, V. A.; Akst, D. V.

    2017-09-01

    The rational technology for the production of ceramic bricks with a defect-free structure from coal mining and processing wastes was developed. The results of comparison of physical and mechanical properties and the structure of ceramic bricks manufactured from overburden rocks and waste coal with traditional for semi-dry pressing mass preparation and according to the developed method are given. It was established that a homogeneous, defect-free brick texture obtained from overburden rocks of open-pit mines and waste coal improves the quality of ceramic wall materials produced by the method of compression molding by more than 1.5 times compared to the brick with a traditional mass preparation.

  11. Summary of rock mechanics work completed for Posiva before 2005

    International Nuclear Information System (INIS)

    Hudson, J.A.; Johansson, E.

    2006-06-01

    To plan Posiva's rock mechanics work for 2005-2006 and beyond, it was necessary to have a clear understanding of the individual components of work that had been completed for Posiva before 2005 and to assess the cumulative rock mechanics knowledge base. This review summarizes the 80 individual completed documents, which include rock mechanics reports and other reports containing rock mechanics material. They are summarised within a structured framework of rock properties, analyses and the effects of excavation. Following the introductory section, the method of structuring the rock mechanics information is presented. Then the tabulation highlighting the features of all the previous rock mechanics work is explained. This tabulation forms the Appendix; the content of each rock mechanics report that has been produced is summarized via the table headings of document number, subject area, document reference, subject matter, objectives, methodology, highlighted figures, conclusions and comments. In addition to the direct usefulness of the tabulation in summarizing each report, it has been possible to draw overall conclusions: Information has also been obtained worldwide, especially Sweden and Canada; The rock stress state has been measured but further work is required related both to in situ measurements and numerical modelling to study, e.g., the influence of deformation zones on the local stress state; The intact rock has been extensively studied: there is a good knowledge of the parameters and their values, including the anisotropic nature of the site rocks; The geometry of the fractures is included in the geological characterisation but more rock mechanics work is required on the mechanical properties; The mechanical properties of the deformation zones have not been studied in detail; The thermal properties of the site rock are relatively well understood; A new classification has been developed for constructability and long-term safety assessment. This classification

  12. In-stream chemical neutralization: A whole watershed approach to mitigating acid mine drainage

    International Nuclear Information System (INIS)

    Britt, D.L.

    1994-01-01

    The North Branch of the Potomac River is adversely affected by acid mine drainage (AMD) throughout its entire length. As an alternative to mine-mouth treatment methods an in-stream AMD-neutralization demonstration program for an approximately 25-mile segment of the North Branch of the Potomac River was designed and implemented. This river segment was ranked as the highest priority site in Maryland for a demonstration project owing to its combination of very poor water quality and excellent potential for supporting a recreational sport fishery in the absence of toxic metal and acid loadings. A whole-watershed approach employing Scandinavian doser technologies and calcium carbonate neutralizing agents is the basis for the North Branch Potomac River demonstration project. The project involves four phases: feasibility (1), design (2), implementation (3), and monitoring (4). This watershed approach to mitigating AMD is expected to restore circumneutrial water quality and to promote desirable fishery resources throughout the mainstem and selected tributaries of the North Branch of the Potomac River Upstream of Jennings Randolph Dam. This paper summarizes Phases 1--3 of the demonstration project

  13. Characteristics and genesis of porphyroclastic lava rock in Xiangshan

    International Nuclear Information System (INIS)

    Zhou Xiaohua; Wang Zhuning

    2012-01-01

    Due to the transitional characteristics of porphyroclastic lava rock in Xiangshan of Jiangxi province, there are a variety of views on its genesis, petrographic attribution. This is because the marginal facies of the porphyroclastic lava is with ignimbrite and tuff characteristics, its transition phase has the characteristics of lava, and its intermediate phase has the feature of sub-volcanic rocks, further more, different texture of the rocks bears transition relationship. By the study of mineral composition, REE pattern, trace elements, isotopes, we put forward that the porphyroclastic lava is formed by the remelting of basement metamorphic rocks. The rocks was believed to be formed in the environment similar to volcanics and subvolcanics, and quite different to plutonic rocks due to the features of low-structure of potassium feldspar phenocrysts and solution mechanism, because the porphyroclastic lava phenocrysts occurs as fragments and maybe related to cryptoexplosion. Therefore the rocks was believed to belong to the volcano extrusive facies. (authors)

  14. Rock mechanics studies for SMES

    International Nuclear Information System (INIS)

    Haimson, B.C.

    1981-01-01

    Superconducting magnetic energy storage (SMES) systems capable of storing thousands of MWh develop tremendous magnetically induced forces when charged. To prevent rutpure of the magnets these forces must be confined. Bedrock offers a practical and relatively inexpensive magnet containment structure. This paper examines the need for rock mechanics research in connection with the construction and use of SMES rock caverns; the unique problems related to housing superconducting magnets in bedrock; site investigations of granite, quartzite and dolomite deposits in Wisconsin; and cavern design requirements to assure cavern stability and limited deformation under the expected mechanical leads. Recommendations are made for siting SMES caverns

  15. Structural and petrophysical characterization: from outcrop rock analogue to reservoir model of deep geothermal prospect in Eastern France

    Science.gov (United States)

    Bertrand, Lionel; Géraud, Yves; Diraison, Marc; Damy, Pierre-Clément

    2017-04-01

    The Scientific Interest Group (GIS) GEODENERGIES with the REFLET project aims to develop a geological and reservoir model for fault zones that are the main targets for deep geothermal prospects in the West European Rift system. In this project, several areas are studied with an integrated methodology combining field studies, boreholes and geophysical data acquisition and 3D modelling. In this study, we present the results of reservoir rock analogues characterization of one of these prospects in the Valence Graben (Eastern France). The approach used is a structural and petrophysical characterization of the rocks outcropping at the shoulders of the rift in order to model the buried targeted fault zone. The reservoir rocks are composed of fractured granites, gneiss and schists of the Hercynian basement of the graben. The matrix porosity, permeability, P-waves velocities and thermal conductivities have been characterized on hand samples coming from fault zones at the outcrop. Furthermore, fault organization has been mapped with the aim to identify the characteristic fault orientation, spacing and width. The fractures statistics like the orientation, density, and length have been identified in the damaged zones and unfaulted blocks regarding the regional fault pattern. All theses data have been included in a reservoir model with a double porosity model. The field study shows that the fault pattern in the outcrop area can be classified in different fault orders, with first order scale, larger faults distribution controls the first order structural and lithological organization. Between theses faults, the first order blocks are divided in second and third order faults, smaller structures, with characteristic spacing and width. Third order fault zones in granitic rocks show a significant porosity development in the fault cores until 25 % in the most locally altered material, as the damaged zones develop mostly fractures permeabilities. In the gneiss and schists units, the

  16. Rock fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Brown, W.S.; Green, S.J.; Hakala, W.W.; Hustrulid, W.A.; Maurer, W.C. (eds.)

    1976-01-01

    Experts in rock mechanics, mining, excavation, drilling, tunneling and use of underground space met to discuss the relative merits of a wide variety of rock fragmentation schemes. Information is presented on novel rock fracturing techniques; tunneling using electron beams, thermocorer, electric spark drills, water jets, and diamond drills; and rock fracturing research needs for mining and underground construction. (LCL)

  17. Investigations on the Influence of the In-Stream Pylon and Strut on the Performance of a Scramjet Combustor

    Directory of Open Access Journals (Sweden)

    Hao Ouyang

    2014-01-01

    Full Text Available The influence of the in-stream pylon and strut on the performance of scramjet combustor was experimentally and numerically investigated. The experiments were conducted with a direct-connect supersonic model combustor equipped with multiple cavities. The entrance parameter of combustor corresponds to scramjet flight Mach number 4.0 with a total temperature of 947 K. The research results show that, compared with the scramjet combustor without pylon and strut, the wall pressure and the thrust of the scramjet increase due to the improvement of mixing and combustion effect due to the pylon and strut. The total pressure loss caused by the strut is considerable whereas pylon influence is slight.

  18. Improved RMR Rock Mass Classification Using Artificial Intelligence Algorithms

    Science.gov (United States)

    Gholami, Raoof; Rasouli, Vamegh; Alimoradi, Andisheh

    2013-09-01

    Rock mass classification systems such as rock mass rating (RMR) are very reliable means to provide information about the quality of rocks surrounding a structure as well as to propose suitable support systems for unstable regions. Many correlations have been proposed to relate measured quantities such as wave velocity to rock mass classification systems to limit the associated time and cost of conducting the sampling and mechanical tests conventionally used to calculate RMR values. However, these empirical correlations have been found to be unreliable, as they usually overestimate or underestimate the RMR value. The aim of this paper is to compare the results of RMR classification obtained from the use of empirical correlations versus machine-learning methodologies based on artificial intelligence algorithms. The proposed methods were verified based on two case studies located in northern Iran. Relevance vector regression (RVR) and support vector regression (SVR), as two robust machine-learning methodologies, were used to predict the RMR for tunnel host rocks. RMR values already obtained by sampling and site investigation at one tunnel were taken into account as the output of the artificial networks during training and testing phases. The results reveal that use of empirical correlations overestimates the predicted RMR values. RVR and SVR, however, showed more reliable results, and are therefore suggested for use in RMR classification for design purposes of rock structures.

  19. Total porosity of carbonate reservoir rocks by X-ray microtomography in two different spatial resolutions

    International Nuclear Information System (INIS)

    Nagata, Rodrigo; Appoloni, Carlos R.; Marques, Leonardo C.; Fernandes, Celso P.

    2011-01-01

    Carbonate reservoir rocks contain more than 50% of world's petroleum. To know carbonate rocks' structural properties is quite important to petroleum extraction. One of their main structural properties is the total porosity, which shows the rock's capacity to stock petroleum. In recent years, the X-ray microtomography had been used to analyze the structural parameters of reservoir rocks. Such nondestructive technique generates images of the samples' internal structure, allowing the evaluation of its properties. The spatial resolution is a measurement parameter that indicates the smallest structure size observable in a sample. It is possible to measure one sample using two or more different spatial resolutions in order to evaluate the samples' pore scale. In this work, two samples of the same sort of carbonate rock were measured, and in each measurement a different spatial resolution (17 μm and 7 μm) was applied. The obtained results showed that with the better resolution it was possible to measure 8% more pores than with the poorer resolution. Such difference provides us with good expectations about such approach to study the pore scale of carbonate rocks. (author)

  20. Rock mechanics for hard rock nuclear waste repositories

    International Nuclear Information System (INIS)

    Heuze, F.E.

    1981-09-01

    The mined geologic burial of high level nuclear waste is now the favored option for disposal. The US National Waste Terminal Storage Program designed to achieve this disposal includes an extensive rock mechanics component related to the design of the wastes repositories. The plan currently considers five candidate rock types. This paper deals with the three hard rocks among them: basalt, granite, and tuff. Their behavior is governed by geological discontinuities. Salt and shale, which exhibit behavior closer to that of a continuum, are not considered here. This paper discusses both the generic rock mechanics R and D, which are required for repository design, as well as examples of projects related to hard rock waste storage. The examples include programs in basalt (Hanford/Washington), in granitic rocks (Climax/Nevada Test Site, Idaho Springs/Colorado, Pinawa/Canada, Oracle/Arizona, and Stripa/Sweden), and in tuff

  1. Elastic Rock Heterogeneity Controls Brittle Rock Failure during Hydraulic Fracturing

    Science.gov (United States)

    Langenbruch, C.; Shapiro, S. A.

    2014-12-01

    For interpretation and inversion of microseismic data it is important to understand, which properties of the reservoir rock control the occurrence probability of brittle rock failure and associated seismicity during hydraulic stimulation. This is especially important, when inverting for key properties like permeability and fracture conductivity. Although it became accepted that seismic events are triggered by fluid flow and the resulting perturbation of the stress field in the reservoir rock, the magnitude of stress perturbations, capable of triggering failure in rocks, can be highly variable. The controlling physical mechanism of this variability is still under discussion. We compare the occurrence of microseismic events at the Cotton Valley gas field to elastic rock heterogeneity, obtained from measurements along the treatment wells. The heterogeneity is characterized by scale invariant fluctuations of elastic properties. We observe that the elastic heterogeneity of the rock formation controls the occurrence of brittle failure. In particular, we find that the density of events is increasing with the Brittleness Index (BI) of the rock, which is defined as a combination of Young's modulus and Poisson's ratio. We evaluate the physical meaning of the BI. By applying geomechanical investigations we characterize the influence of fluctuating elastic properties in rocks on the probability of brittle rock failure. Our analysis is based on the computation of stress fluctuations caused by elastic heterogeneity of rocks. We find that elastic rock heterogeneity causes stress fluctuations of significant magnitude. Moreover, the stress changes necessary to open and reactivate fractures in rocks are strongly related to fluctuations of elastic moduli. Our analysis gives a physical explanation to the observed relation between elastic heterogeneity of the rock formation and the occurrence of brittle failure during hydraulic reservoir stimulations. A crucial factor for understanding

  2. Rock.XML - Towards a library of rock physics models

    Science.gov (United States)

    Jensen, Erling Hugo; Hauge, Ragnar; Ulvmoen, Marit; Johansen, Tor Arne; Drottning, Åsmund

    2016-08-01

    Rock physics modelling provides tools for correlating physical properties of rocks and their constituents to the geophysical observations we measure on a larger scale. Many different theoretical and empirical models exist, to cover the range of different types of rocks. However, upon reviewing these, we see that they are all built around a few main concepts. Based on this observation, we propose a format for digitally storing the specifications for rock physics models which we have named Rock.XML. It does not only contain data about the various constituents, but also the theories and how they are used to combine these building blocks to make a representative model for a particular rock. The format is based on the Extensible Markup Language XML, making it flexible enough to handle complex models as well as scalable towards extending it with new theories and models. This technology has great advantages as far as documenting and exchanging models in an unambiguous way between people and between software. Rock.XML can become a platform for creating a library of rock physics models; making them more accessible to everyone.

  3. Structural and electronic properties of TiX (X=N, As) in rock salt and zinc blende phase: A DFT study

    Energy Technology Data Exchange (ETDEWEB)

    Verma, U. P.; Nayak, V. [School of Studies in Phyics, jiwaji University, Gwalior-474011 (India)

    2016-05-23

    Quantum mechanical first principle calculations have been performed to study the electronic and structural properties of TiN and TiAs in zinc blende (ZB) and rock salt (RS) structures. The full-potential linearized augmented plane wave (FP-LAPW) method has been used within the framework of density functional theory (DFT). The exchange correlation functional has been solved employing generalized gradient approximation (GGA). Our predicted results for lattice constants are in good agreement with the earlier findings. The electronic band structures of TiX are metallic in both the phases.

  4. Experimental research on the electromagnetic radiation (EMR) characteristics of cracked rock.

    Science.gov (United States)

    Song, Xiaoyan; Li, Xuelong; Li, Zhonghui; Cheng, Fuqi; Zhang, Zhibo; Niu, Yue

    2018-03-01

    Coal rock would emit the electromagnetic radiation (EMR) while deformation and fracture, and there exists structural body in the coal rock because of mining and geological structure. In this paper, we conducted an experimental test the EMR characteristics of cracked rock under loading. Results show that crack appears firstly in the prefabricated crack tip then grows stably parallel to the maximum principal stress, and the coal rock buckling failure is caused by the wing crack tension. Besides, the compressive strength significantly decreases because of the precrack, and the compressive strength increases with the crack angle. Intact rock EMR increases with the loading, and the cracked rock EMR shows stage and fluctuant characteristics. The bigger the angle, the more obvious the stage and fluctuant characteristics, that is EMR becomes richer. While the cracked angle is little, EMR is mainly caused by the electric charge rapid separates because of friction sliding. While the cracked angle is big, there is another significant contribution to EMR, which is caused by the electric dipole transient of crack expansion. Through this, we can know more clear about the crack extends route and the corresponding influence on the EMR characteristic and mechanism, which has important theoretical and practical significance to monitor the coal rock dynamical disasters.

  5. Aespoe Hard Rock Laboratory. Analysis of fracture networks based on the integration of structural and hydrogeological observations on different scales

    Energy Technology Data Exchange (ETDEWEB)

    Bossart, P. [Geotechnical Inst. Ltd., Bern (Switzerland); Hermanson, Jan [Golder Associates, Stockholm (Sweden); Mazurek, M. [Univ. of Bern (Switzerland)

    2001-05-01

    Fracture networks at Aespoe have been studied for several rock types exhibiting different degrees of ductile and brittle deformation, as well as on different scales. Mesoscopic fault systems have been characterised and classified in an earlier report, this report focuses mainly on fracture networks derived on smaller scales, but also includes mesoscopic and larger scales. The TRUE-1 block has been selected for detailed structural analysis on a small scale due to the high density of relevant information. In addition to the data obtained from core materials, structural maps, BIP data and the results of hydro tests were synthesised to derive a conceptual structural model. The approach used to derive this conceptual model is based on the integration of deterministic structural evidence, probabilistic information and both upscaling and downscaling of observations and concepts derived on different scales. Twelve fracture networks mapped at different sites and scales and exhibiting various styles of tectonic deformation were analysed for fractal properties and structural and hydraulic interconnectedness. It was shown that these analysed fracture networks are not self-similar. An important result is the structural and hydraulic interconnectedness of fracture networks on all scales in the Aespoe rocks, which is further corroborated by geochemical evidence. Due to the structural and hydraulic interconnectedness of fracture systems on all scales at Aespoe, contaminants from waste canisters placed in tectonically low deformation environments would be transported - after having passed through the engineered barriers -from low-permeability fractures towards higher permeability fractures and may thus eventually reach high-permeability features.

  6. Aespoe Hard Rock Laboratory. Analysis of fracture networks based on the integration of structural and hydrogeological observations on different scales

    International Nuclear Information System (INIS)

    Bossart, P.; Hermanson, Jan; Mazurek, M.

    2001-05-01

    Fracture networks at Aespoe have been studied for several rock types exhibiting different degrees of ductile and brittle deformation, as well as on different scales. Mesoscopic fault systems have been characterised and classified in an earlier report, this report focuses mainly on fracture networks derived on smaller scales, but also includes mesoscopic and larger scales. The TRUE-1 block has been selected for detailed structural analysis on a small scale due to the high density of relevant information. In addition to the data obtained from core materials, structural maps, BIP data and the results of hydro tests were synthesised to derive a conceptual structural model. The approach used to derive this conceptual model is based on the integration of deterministic structural evidence, probabilistic information and both upscaling and downscaling of observations and concepts derived on different scales. Twelve fracture networks mapped at different sites and scales and exhibiting various styles of tectonic deformation were analysed for fractal properties and structural and hydraulic interconnectedness. It was shown that these analysed fracture networks are not self-similar. An important result is the structural and hydraulic interconnectedness of fracture networks on all scales in the Aespoe rocks, which is further corroborated by geochemical evidence. Due to the structural and hydraulic interconnectedness of fracture systems on all scales at Aespoe, contaminants from waste canisters placed in tectonically low deformation environments would be transported - after having passed through the engineered barriers -from low-permeability fractures towards higher permeability fractures and may thus eventually reach high-permeability features

  7. Lined rock caverns for the storage of hazardous waste

    International Nuclear Information System (INIS)

    Semprich, S.; Speidel, S.R.; Schneider, H.J.

    1987-01-01

    For reasons of environmental protection the storage of hazardous waste in unlined rock caverns is possible to a very limited extent only. Therefore, the authors have recently developed technologies for the lining and sealing of rock caverns. In the process, sealing systems of synthetic materials or metals have proved suitable. Synthetic materials can be used in the form of either sheets or coatings with various materials such as epoxy resins, polyethylenes etc. being used. Metal sealings consist of thin sheets or foils which are either welded or bonded. In either case, the structural design must provide for a leakage control possibility. The article describes the design principles, the structural and operational aspects as well as the control measures with regard to the planning and execution of lined rock caverns for the storage of hazardous waste

  8. Rock burst governance of working face under igneous rock

    Science.gov (United States)

    Chang, Zhenxing; Yu, Yue

    2017-01-01

    As a typical failure phenomenon, rock burst occurs in many mines. It can not only cause the working face to cease production, but also cause serious damage to production equipment, and even result in casualties. To explore how to govern rock burst of working face under igneous rock, the 10416 working face in some mine is taken as engineering background. The supports damaged extensively and rock burst took place when the working face advanced. This paper establishes the mechanical model and conducts theoretical analysis and calculation to predict the fracture and migration mechanism and energy release of the thick hard igneous rock above the working face, and to obtain the advancing distance of the working face when the igneous rock fractures and critical value of the energy when rock burst occurs. Based on the specific conditions of the mine, this paper put forward three kinds of governance measures, which are borehole pressure relief, coal seam water injection and blasting pressure relief.

  9. Strategy for future laboratory rock mechanics programs

    International Nuclear Information System (INIS)

    Butcher, B.M.; Jones, A.K.

    1985-01-01

    A strategy for future experimental rock mechanics laboratory programs at Sandia National Laboratories is described. This strategy is motivated by the need for long range planning of rock mechanics programs addressing the stability of complex underground structures, changes in in situ stress states during resource recovery and underground explosion technology. It is based on: (1) recent advances in underground structure stability analysis which make three-dimensional calculations feasible, and (2) new developments in load path control of laboratory stress-strain tests which permit duplication of stress and strain histories in critical parts of a structure, as determined by numerical analysis. The major constraint in the strategy is the assumption that there are no in situ joint features or sample size effects which might prevent simulation of in situ response in the laboratory. 3 refs., 5 figs

  10. The Folding and Fracturing of Rocks: A milestone publication in Structural Geology research

    Science.gov (United States)

    Lisle, Richard; Bastida, Fernando

    2017-04-01

    In the field of structural geology, the textbook written by John G Ramsay in 1967, reprinted in 2004 and translated into Spanish and Chinese, is the one that has made the greatest research impact. With citations exceeding 4000 (Google Scholar) it far surpasses books by other authors on the subject, with this figure only being approached by his later book Modern Structural Geology (Ramsay and Huber 1983). In this paper we consider the factors that account for the book's success despite the fact that it is a research-level text beyond the comfort zone of most undergraduates. We also take stock of other measures of the book's success; the way it influenced the direction subsequent research effort. We summarize the major advances in structural geology that were prompted by Ramsay's book. Finally we consider the book's legacy. Before the publication of the book in 1967 structural geology had been an activity that had concentrated almost exclusively on geological mapping aimed at establishing the geometrical configuration of rock units. In fact, Ramsay himself has produced beautiful examples of such maps. However, the book made us aware that the geometrical pattern is controlled by the spatial variation of material properties, the boundary conditions, the deformation environment and the temporal variation of stresses. With the arrival of the book Structural Geology came of age as a modern scientific discipline that employed a range of tools such as those of physics, maths and engineering as well as those of geology.

  11. Rock support of the L3 experimental hall complex

    International Nuclear Information System (INIS)

    Laughton, C.

    1990-06-01

    The methods of excavation and support selected for the LEP works are discussed in this paper. The excavation of the halls and chambers in discrete passes, from the roof down, and their temporary support by patterned fully bonded rock bolts and shotcrete ensured that mass deformations were contained. When working in soft rock materials where discontinuity, elastic and possibly plastic deformations may each play an important role in the overall rock structure stability, it is of paramount importance to systematically monitor the behavior of the rock in-situ. The use of instrumentation to indicate location, direction, levels, and rate of movement is essential to ensure that a safe, efficient and economical mining operation can be undertaken, and that any remedial action will be taken at the appropriate time. The use of the New Austrian Tunneling support mechanisms allowed the engineer greater flexibility in handling local reinforcement of the rock structure if superficial or relatively deep-seated instability was encountered. However, in the case where second linings are to be accommodated and flexible support mechanisms used, care should be taken to foresee over-excavation in weaker zones to allow for larger displacements prior to the attainment of confinement-convergence equilibria. 4 refs., 7 figs

  12. Structural characterization and numerical simulations of flow properties of standard and reservoir carbonate rocks using micro-tomography

    Science.gov (United States)

    Islam, Amina; Chevalier, Sylvie; Sassi, Mohamed

    2018-04-01

    With advances in imaging techniques and computational power, Digital Rock Physics (DRP) is becoming an increasingly popular tool to characterize reservoir samples and determine their internal structure and flow properties. In this work, we present the details for imaging, segmentation, as well as numerical simulation of single-phase flow through a standard homogenous Silurian dolomite core plug sample as well as a heterogeneous sample from a carbonate reservoir. We develop a procedure that integrates experimental results into the segmentation step to calibrate the porosity. We also look into using two different numerical tools for the simulation; namely Avizo Fire Xlab Hydro that solves the Stokes' equations via the finite volume method and Palabos that solves the same equations using the Lattice Boltzmann Method. Representative Elementary Volume (REV) and isotropy studies are conducted on the two samples and we show how DRP can be a useful tool to characterize rock properties that are time consuming and costly to obtain experimentally.

  13. For Those About to Rock : Naislaulajat rock-genressä

    OpenAIRE

    Herranen, Linda

    2015-01-01

    For those about to rock – naislaulajat rock-genressä antaa lukijalleen kokonaisvaltaisen käsityksen naisista rock-genressä: rockin historiasta, sukupuolittuneisuudesta, seksismistä, suomalaisten naislaulajien menestyksestä. Työn aineisto on koottu aihepiirin kirjallisuudesta ja alalla toimiville naislaulajille teetettyjen kyselyiden tuloksista. Lisäksi avaan omia kokemuksiani ja ajatuksiani, jotta näkökulma naisista rock-genressä tulisi esille mahdollisimman monipuolisesti. Ajatus aihees...

  14. Proceedings of the 3. Canada-US rock mechanics symposium and 20. Canadian rock mechanics symposium : rock engineering 2009 : rock engineering in difficult conditions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This conference provided a forum for geologists, mining operators and engineers to discuss the application of rock mechanics in engineering designs. Members of the scientific and engineering communities discussed challenges and interdisciplinary elements involved in rock engineering. New geological models and methods of characterizing rock masses and ground conditions in underground engineering projects were discussed along with excavation and mining methods. Papers presented at the conference discussed the role of rock mechanics in forensic engineering. Geophysics, geomechanics, and risk-based approaches to rock engineering designs were reviewed. Issues related to high pressure and high flow water conditions were discussed, and new rock physics models designed to enhance hydrocarbon recovery were presented. The conference featured 84 presentations, of which 9 have been catalogued separately for inclusion in this database. tabs., figs.

  15. 3D Printing and Digital Rock Physics for the Geosciences

    Science.gov (United States)

    Martinez, M. J.; Yoon, H.; Dewers, T. A.

    2014-12-01

    Imaging techniques for the analysis of porous structures have revolutionized our ability to quantitatively characterize geomaterials. For example, digital representations of rock from CT images and physics modeling based on these pore structures provide the opportunity to further advance our quantitative understanding of fluid flow, geomechanics, and geochemistry, and the emergence of coupled behaviors. Additive manufacturing, commonly known as 3D printing, has revolutionized production of custom parts, to the point where parts might be cheaper to print than to make by traditional means in a plant and ship. Some key benefits of additive manufacturing include short lead times, complex shapes, parts on demand, zero required inventory and less material waste. Even subtractive processing, such as milling and etching, may be economized by additive manufacturing. For the geosciences, recent advances in 3D printing technology may be co-opted to print reproducible porous structures derived from CT-imaging of actual rocks for experimental testing. The use of 3D printed microstructure allows us to surmount typical problems associated with sample-to-sample heterogeneity that plague rock physics testing and to test material response independent from pore-structure variability. Together, imaging, digital rocks and 3D printing potentially enables a new workflow for understanding coupled geophysical processes in a real, but well-defined setting circumventing typical issues associated with reproducibility, enabling full characterization and thus connection of physical phenomena to structure. In this talk we will discuss the possibilities that the marriage of these technologies can bring to geosciences, including examples from our current research initiatives in developing constitutive laws for transport and geomechanics via digital rock physics. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of

  16. Rock Burst Monitoring by Integrated Microseismic and Electromagnetic Radiation Methods

    Science.gov (United States)

    Li, Xuelong; Wang, Enyuan; Li, Zhonghui; Liu, Zhentang; Song, Dazhao; Qiu, Liming

    2016-11-01

    For this study, microseismic (MS) and electromagnetic radiation (EMR) monitoring systems were installed in a coal mine to monitor rock bursts. The MS system monitors coal or rock mass ruptures in the whole mine, whereas the EMR equipment monitors the coal or rock stress in a small area. By analysing the MS energy, number of MS events, and EMR intensity with respect to rock bursts, it has been shown that the energy and number of MS events present a "quiet period" 1-3 days before the rock burst. The data also show that the EMR intensity reaches a peak before the rock burst and this EMR intensity peak generally corresponds to the MS "quiet period". There is a positive correlation between stress and EMR intensity. Buckling failure of coal or rock depends on the rheological properties and occurs after the peak stress in the high-stress concentration areas in deep mines. The MS "quiet period" before the rock burst is caused by the heterogeneity of the coal and rock structures, the transfer of high stress into internal areas, locked patches, and self-organized criticality near the stress peak. This study increases our understanding of coal and rock instability in deep mines. Combining MS and EMR to monitor rock burst could improve prediction accuracy.

  17. Data to support statistical modeling of instream nutrient load based on watershed attributes, southeastern United States, 2002

    Science.gov (United States)

    Hoos, Anne B.; Terziotti, Silvia; McMahon, Gerard; Savvas, Katerina; Tighe, Kirsten C.; Alkons-Wolinsky, Ruth

    2008-01-01

    This report presents and describes the digital datasets that characterize nutrient source inputs, environmental characteristics, and instream nutrient loads for the purpose of calibrating and applying a nutrient water-quality model for the southeastern United States for 2002. The model area includes all of the river basins draining to the south Atlantic and the eastern Gulf of Mexico, as well as the Tennessee River basin (referred to collectively as the SAGT area). The water-quality model SPARROW (SPAtially-Referenced Regression On Watershed attributes), developed by the U.S. Geological Survey, uses a regression equation to describe the relation between watershed attributes (predictors) and measured instream loads (response). Watershed attributes that are considered to describe nutrient input conditions and are tested in the SPARROW model for the SAGT area as source variables include atmospheric deposition, fertilizer application to farmland, manure from livestock production, permitted wastewater discharge, and land cover. Watershed and channel attributes that are considered to affect rates of nutrient transport from land to water and are tested in the SAGT SPARROW model as nutrient-transport variables include characteristics of soil, landform, climate, reach time of travel, and reservoir hydraulic loading. Datasets with estimates of each of these attributes for each individual reach or catchment in the reach-catchment network are presented in this report, along with descriptions of methods used to produce them. Measurements of nutrient water quality at stream monitoring sites from a combination of monitoring programs were used to develop observations of the response variable - mean annual nitrogen or phosphorus load - in the SPARROW regression equation. Instream load of nitrogen and phosphorus was estimated using bias-corrected log-linear regression models using the program Fluxmaster, which provides temporally detrended estimates of long-term mean load well

  18. Monitoring of Pre-Load on Rock Bolt Using Piezoceramic-Transducer Enabled Time Reversal Method.

    Science.gov (United States)

    Huo, Linsheng; Wang, Bo; Chen, Dongdong; Song, Gangbing

    2017-10-27

    Rock bolts ensure structural stability for tunnels and many other underground structures. The pre-load on a rock bolt plays an important role in the structural reinforcement and it is vital to monitor the pre-load status of rock bolts. In this paper, a rock bolt pre-load monitoring method based on the piezoceramic enabled time reversal method is proposed. A lead zirconate titanate (PZT) patch transducer, which works as an actuator to generate stress waves, is bonded onto the anchor plate of the rock bolt. A smart washer, which is fabricated by sandwiching a PZT patch between two metal rings, is installed between the hex nut and the anchor plate along the rock bolt. The smart washer functions as a sensor to detect the stress wave. With the increase of the pre-load values on the rock bolt, the effective contact surface area between the smart washer and the anchor plate, benefiting the stress wave propagation crossing the contact surface. With the help of time reversal technique, experimental results reveal that the magnitude of focused signal clearly increases with the increase of the pre-load on a rock bolt before the saturation which happens beyond a relatively high value of the pre-load. The proposed method provides an innovative and real time means to monitor the pre-load level of a rock bolt. By employing this method, the pre-load degradation process on a rock bolt can be clearly monitored. Please note that, currently, the proposed method applies to only new rock bolts, on which it is possible to install the PZT smart washer.

  19. Relative scale and the strength and deformability of rock masses

    Science.gov (United States)

    Schultz, Richard A.

    1996-09-01

    The strength and deformation of rocks depend strongly on the degree of fracturing, which can be assessed in the field and related systematically to these properties. Appropriate Mohr envelopes obtained from the Rock Mass Rating (RMR) classification system and the Hoek-Brown criterion for outcrops and other large-scale exposures of fractured rocks show that rock-mass cohesive strength, tensile strength, and unconfined compressive strength can be reduced by as much as a factor often relative to values for the unfractured material. The rock-mass deformation modulus is also reduced relative to Young's modulus. A "cook-book" example illustrates the use of RMR in field applications. The smaller values of rock-mass strength and deformability imply that there is a particular scale of observation whose identification is critical to applying laboratory measurements and associated failure criteria to geologic structures.

  20. Art Rocks with Rock Art!

    Science.gov (United States)

    Bickett, Marianne

    2011-01-01

    This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

  1. Study of rock structures by geotomography 5

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Yul; Kim, Yoo Sung; Hyun, Hye Ja [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

    1995-12-01

    Since computerized axial tomography has revolutionized medical x-ray imaging, geotomography has found its big impact in the field of seismic exploration because of its ability to clearly image subsurface velocity structures and attenuation characteristics of the formations. For example, lateral or vertical inhomogeneities may generate distortions in the observed arrival time and/or amplitude of seismic waves. By evaluating such distortions, one can locate the inhomogeneities which may not be detected easily by the conventional surface seismic survey. Recently, seismic geotomography has been used as an efficient aid for solving various, geophysical problems such as evaluating radioactive waste repository, detecting fracture zones in crystalline rocks, dam site investigation, cavity detection and so on. However, application of seismic methods to such environmental problems as above has rarely been conducted, thus many problems including development of suitable equipment and processing facilities still to be attacked. The objectives of this project can be categorized in three major parts. The first is an establishment of the geotomographical processing system on personal computers. This includes the development of an effective routines useful for the first onsets picking. The second is associated with the development of borehole source and receiver systems which provide meaningful data for geotomography. The small and light but powerful borehole acquisition system which is suitable for our field environment is needed to be developed. The third is concerned with the establishment of borehole scanner (televiewer) system for obtaining detailed information about fractures, bedding planes, geothermal reservoirs etc. It is evident that the above mentioned developments should represent our potential of crosshole seismic methods for the exploration of subsurface. The purpose of this investigation is to realize the highly efficient seismic methods i.e. (Abstract Truncated)

  2. Surrounding rock stress analysis of underground high level waste repository

    International Nuclear Information System (INIS)

    Liu Wengang; Wang Ju; Wang Guangdi

    2006-01-01

    During decay of nuclear waste, enormous energy was released, which results in temperature change of surrounding rock of depository. Thermal stress was produced because thermal expansion of rock was controlled. Internal structure of surrounding rock was damaged and strength of rock was weakened. So, variation of stress was a dynamic process with the variation of temperature. BeiShan region of Gansu province was determined to be the depository field in the future, it is essential to make research on granite in this region. In the process of experiment, basic physical parameters of granite were analyzed preliminary with MTS. Long range temperature and stress filed was simulated considering the damage effect of surrounding rock, and rules of temperature and stress was achieved. (authors)

  3. Microscopic study of rock for estimating long-term behavior

    International Nuclear Information System (INIS)

    Ichikawa, Yasuaki

    2002-03-01

    Micro-structure of rock plays a essential role for their long-term behavior. For elucidating long-term characteristics of granite we here present the followings: 1) Conforcal Laser Scanning Microscope (LSM) observation of joint surfaces of granite and Fourier analysis, 2) characterization of the mechanism of microcrack initiation and propagation observed by stereoscopic microscope under uniaxial/triaxial compression and relaxation tests, 3) observation of microcrack initiation and propagation by LSM under uniaxial compression, and 4) a viscoelastic homogenization theory to predict the long-term behavior of micro/macro-level stress for granite. Rock image processing and analysis become a fundamental procedure to determine rock surface discontinuities. But the complexity of rock surface discontinuities seems beyond the manual image processing method. In Chapter 2 a Conforcal Laser Scanning Microscope that can acquire three-dimensional images is introduced to observe the rock roughness of a discontinuity. Then, scanning three-dimensional images are changed its data form in order to adapt various image analysis programs, and granitic rock roughness of discontinuities are displayed by graphic images. For example, these datas are analyzed by Discrete Fourier Transformation (DFT) program and Inverse Discrete Fourier Transformation (IDFT) program. Microcrack generation and propagation play an essential role to predict the long-term behavior of rock. In Chapter 3 a progressive development of cracking in granite is revealed by using stereoscopic microscope under triaxial compression condition and by using LSM under uniaxial compression condition. With a viscoelastic theory applied in homogenization method, we can calculate macro behavior of medium influenced by its micro structure by analyse the long-term time-dependent behavior of granite under the same condition to the relaxation experiment. (author)

  4. An analogue of long-term stability of flow-path structure in crystalline rocks distributed in the orogenic belt, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, H. [Nagoya University, University Museum Material Research Section, 464-8601, Chikusa, Nagoya, 464-8601 (Japan)]. E-mail: dora@num.nagoya-u.ac.jp; Takeuchi, M. E-mail: takeuchi@eps.nagoya-u.ac.jp

    2004-07-01

    In the orogenic belt, in the Japanese islands, crystalline rocks from the youngest to older ages and of different orders have been identified which have formed massive areas. The fracture system observed within these rock masses implies that the groundwater and solute can be conducted through the fracture's network. It is expected that the nuclides can be retarded due to chemical sorption and/or physical retardation by the fracture fillings and fracture open pore geometry. Most of the evaluation framework of the nuclides retardation process in the geological disposal of high level radioactive waste (HLW) is, however, basically taken into account in the present geological state, without changes of structural and mineralogical features, and in its influence on the groundwater flow system over a long period of time. This paper seeks analogous evidence that can provide the confidence of such evaluation methodology and its long-term applicability. Here, we describe the fracture system developed in the crystalline rock with the different ages intruded in the orogenic belt in order to build the long-term fracturing and its 'stability' model. In particular, comparisons with the rock of 1.9-0.8 Ma Takidani Granodiorite (the youngest pluton in the world), ca. 67 Ma of Toki Granite and ca. 117 Ma Kurihashi Granodiorite located in central to northwest Japan suggest a unique characteristic of the fracture forming process and their relatively stable geometrical changing. This analogue enables us to provide a model to build the confidence of a safety context applicable for the geological setting under the orogenic field with a long-term scale. The model may also be useful for other stable tectonic settings as well as for a site characterisation methodology of crystalline rock for HLW geological disposal. (author)

  5. Experimental studies on the effects of bolt parameters on the bearing characteristics of reinforced rock.

    Science.gov (United States)

    Cheng, Liang; Zhang, Yidong; Ji, Ming; Zhang, Kai; Zhang, Minglei

    2016-01-01

    Roadways supported by bolts contain support structures that are built into the rock surrounding the roadway, referred to as reinforced rocks in this paper. Using physical model simulation, the paper investigates the bearing characteristics of the reinforced rock under different bolt parameters with incrementally increased load. The experimental results show that the stress at the measurement point inside the structure varies with the kinetic pressure. The stress increases slowly as the load is initially applied, displays accelerated growth in the middle of the loading application, and decreases or remains constant in the later stage of the loading application. The change in displacement of the surrounding rock exhibits the following characteristics: a slow increase when the load is first applied, accelerated growth in the middle stage, and violent growth in the later stage. There is a good correlation between the change in the measured stress and the change in the surrounding rock displacement. Increasing the density of the bolt support and the length and diameter of the bolt improves the load-bearing performance of the reinforced rock, including its strength, internal peak stress, and residual stress. Bolting improves the internal structure of the surrounding rocks, and the deterioration of the surrounding rock decreases with the distance between the bolt supports.

  6. Structural and chemical variations in phlogopite from lamproitic rocks of the Central Mediterranean region

    Science.gov (United States)

    Lepore, Giovanni O.; Bindi, Luca; Pedrazzi, Giuseppe; Conticelli, Sandro; Bonazzi, Paola

    2017-08-01

    Micas from mafic ultrapotassic rocks with lamproitic affinity from several localities of the Central Mediterranean region were studied through single-crystal X-ray diffraction (SC-XRD), electron microprobe analysis (EMPA) and Secondary Ion Mass Spectrometry (SIMS); Mössbauer Spectroscopy (MöS), when feasible, was also applied to minimise the number of unknown variables and uncertainties. Analysed lamproitic samples cover the most important Central Mediterranean type localities, from Plan d'Albard (Western Alps) to Sisco (Corsica), Montecatini Val di Cecina and Orciatico (Tuscany, Italy) and Torre Alfina (Northern Latium, Italy). The studied crystals show distinctive chemical and structural features; all of them belong to the phlogopite-annite join and crystallise in the 1M polytype, except for micas from Torre Alfina, where both 1M and 2M1 polytypes were found. Studied micas have variable but generally high F and Ti contents, with Mg/(Mg + Fe) ranging from 0.5 to 0.9; 2M1 crystals from Torre Alfina radically differ in chemical composition, showing high contents of Ti and Fe as well as of Al in both tetrahedra and octahedra, leading to distinctive structural distortions, especially in tetrahedral sites. SIMS data indicate that studied micas are generally dehydrogenated with OH contents ranging from 0.2 apfu (atoms per formula unit) for Orciatico and Torre Alfina to 1.4 for Plan d'Albard crystals; this feature is also testified by the length of the c parameter, which decreases with the loss of hydrogen and/or the increase of the F → OH substitution. Chemical and structural data suggest that the entry of high charge octahedral cations is mainly balanced by an oxy mechanism and, to a lesser extent, by a M3 +,4 +-Tschermak substitution. Our data confirm that Ti preferentially partitions into the M2 site and that different Ti and F contents, as well as different K/Al values, are both dependant upon fH2O and the composition of magma rather than controlled by P and T

  7. Centrifuge modeling of rocking-isolated inelastic RC bridge piers.

    Science.gov (United States)

    Loli, Marianna; Knappett, Jonathan A; Brown, Michael J; Anastasopoulos, Ioannis; Gazetas, George

    2014-12-01

    Experimental proof is provided of an unconventional seismic design concept, which is based on deliberately underdesigning shallow foundations to promote intense rocking oscillations and thereby to dramatically improve the seismic resilience of structures. Termed rocking isolation , this new seismic design philosophy is investigated through a series of dynamic centrifuge experiments on properly scaled models of a modern reinforced concrete (RC) bridge pier. The experimental method reproduces the nonlinear and inelastic response of both the soil-footing interface and the structure. To this end, a novel scale model RC (1:50 scale) that simulates reasonably well the elastic response and the failure of prototype RC elements is utilized, along with realistic representation of the soil behavior in a geotechnical centrifuge. A variety of seismic ground motions are considered as excitations. They result in consistent demonstrably beneficial performance of the rocking-isolated pier in comparison with the one designed conventionally. Seismic demand is reduced in terms of both inertial load and deck drift. Furthermore, foundation uplifting has a self-centering potential, whereas soil yielding is shown to provide a particularly effective energy dissipation mechanism, exhibiting significant resistance to cumulative damage. Thanks to such mechanisms, the rocking pier survived, with no signs of structural distress, a deleterious sequence of seismic motions that caused collapse of the conventionally designed pier. © 2014 The Authors Published by John Wiley & Sons Ltd.

  8. Modeling rock specimens through 3D printing: Tentative experiments and prospects

    Science.gov (United States)

    Jiang, Quan; Feng, Xiating; Song, Lvbo; Gong, Yahua; Zheng, Hong; Cui, Jie

    2016-02-01

    Current developments in 3D printing (3DP) technology provide the opportunity to produce rock-like specimens and geotechnical models through additive manufacturing, that is, from a file viewed with a computer to a real object. This study investigated the serviceability of 3DP products as substitutes for rock specimens and rock-type materials in experimental analysis of deformation and failure in the laboratory. These experiments were performed on two types of materials as follows: (1) compressive experiments on printed sand-powder specimens in different shapes and structures, including intact cylinders, cylinders with small holes, and cuboids with pre-existing cracks, and (2) compressive and shearing experiments on printed polylactic acid cylinders and molded shearing blocks. These tentative tests for 3DP technology have exposed its advantages in producing complicated specimens with special external forms and internal structures, the mechanical similarity of its product to rock-type material in terms of deformation and failure, and its precision in mapping shapes from the original body to the trial sample (such as a natural rock joint). These experiments and analyses also successfully demonstrate the potential and prospects of 3DP technology to assist in the deformation and failure analysis of rock-type materials, as well as in the simulation of similar material modeling experiments.

  9. Characterization and differentiation of rock varnish types from different environments by microanalytical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Macholdt, D. S. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Jochum, K. P. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Pöhlker, C. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Arangio, A. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Förster, J. -D. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Stoll, B. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Weis, U. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Weber, B. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Müller, M. [Max Planck Inst. for Polymer Research, Mainz (Germany); Kappl, M. [Max Planck Inst. for Polymer Research, Mainz (Germany); Shiraiwa, M. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Kilcoyne, A. L. D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Weigand, M. [Max Planck Inst. for Intelligent Systems, Stuttgart (Germany); Scholz, D. [Johannes Gutenberg Univ., Mainz (Germany); Haug, G. H. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Al-Amri, A. [King Saud Univ., Riyadh (Saudi Arabia); Andreae, M. O. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; King Saud Univ., Riyadh (Saudi Arabia)

    2017-04-13

    We investigated rock varnishes collected from several locations and environments worldwide by a wide range of microanalytical techniques. These techniques were selected to address the challenges posed by the chemical and structural complexity within the micrometer- to nanometer-sized structures in these geological materials. Femtosecond laser ablation-inductively coupled plasma-mass spectrometry (fs LA-ICP-MS), scanning transmission X-ray microscopy-near edge X-ray adsorption fine structure spectroscopy (STXM-NEXAFS) in combination with scanning electron microscopy (SEM) of focused ion beam (FIB) ultra-thin (100–200 nm) sections, conventional and polarization microscopy, as well as electron paramagnetic resonance (EPR) measurements were used to obtain information about these rock varnishes. Rock varnishes from different environments, which cannot readily be distinguished based on their macroscopic appearance, differ significantly in their constituent elemental mass fractions, e.g., of Mn, Fe, Ni, Co, Ba, and Pb, and their rare earth element (REE) patterns. Structural characteristics such as the particle sizes of embedded dust grains, internal structures such as layers of Mn-, Fe-, and Ca -rich material, and structures such as cavities varied between varnishes from different environments and regions in the world. The EPR spectra were consistent with aged biogenic Mn oxides in all samples, but showed subtle differences between samples of different origin. Our observations allow us to separate rock varnishes into different types, with differences that might be indicators of distinct geneses. Five different types of rock varnish could be distinguished, Type I–V, of which only Type I might be used as potential paleoclimate archive. Each varnish type has specific characteristics in terms of their elemental composition, element distribution, and structures. The combination of element ratios (Mn/Ba, Al/Ni, Mn/REY, Mn/Ce, Mn/Pb, La N /Yb N , and Ce/Ce*), total REE

  10. 78 FR 33051 - Non-Rock Alternatives to Shoreline Protection Demonstration Project (LA-16) Iberia, Jefferson...

    Science.gov (United States)

    2013-06-03

    ... DEPARTMENT OF AGRICULTURE Natural Resources Conservation Service Non-Rock Alternatives to...-Rock Alternatives to Shoreline Protection Demonstration Project (LA-16), Iberia, Jefferson, and... and environmental limitations preclude the use of rock structures. The shoreline protection systems...

  11. Rock Art

    Science.gov (United States)

    Henn, Cynthia A.

    2004-01-01

    There are many interpretations for the symbols that are seen in rock art, but no decoding key has ever been discovered. This article describes one classroom's experiences with a lesson on rock art--making their rock art and developing their own personal symbols. This lesson allowed for creativity, while giving an opportunity for integration…

  12. Dynamic response of shear induced structure solutions in permeable rock

    NARCIS (Netherlands)

    Reuvers, N.J.W.; Spain, D.S.W.; Golombok, M.

    2009-01-01

    Additives for improving the flow uniformity during secondary oil recovery are partially retained in the rock. The flow improval effects continue to be observed even when the chemical solution is succeeded by pure water. Considerable flushing with water is required before the old permeability of the

  13. Sliding and Rocking of Unanchored Components and Structures: Chapter 7.6 ASCE 4 Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    S. R. Jensen

    2011-04-01

    Chapter 7.6 of ASCE 4-Rev 2, Seismic Analysis of Safety-Related Nuclear Structures: Standard and Commentary, provides updated guidance for analysis of rocking and sliding of unanchored structures and components subjected to seismic load. This guidance includes provisions both for simplified approximate energy-based approaches, and for detailed probabilistic time history analysis using nonlinear methods. Factors to be applied to the analytical results are also provided with the intent of ensuring achievement of the 80% non-exceedence probability target of the standard. The present paper surveys the published literature supporting these provisions. The results of available testing and analysis are compared to results produced by both simplified and probabilistic approaches. In addition, adequacy of the standard's provisions for analysis methods and factors is assessed. A comparison is made between the achieved level of conservatism and the standard's non-exceedence probability target.

  14. The ISRM suggested methods for rock characterization, testing and monitoring 2007-2014

    CERN Document Server

    2015-01-01

    This book is a collection of ISRM suggested methods for testing or measuring properties of rocks and rock masses both in the laboratory and in situ, as well as for monitoring the performance of rock engineering structures. The first collection (Yellow Book) has been published in 1981. In order to provide access to all the Suggested Methods in one volume, the ISRM Blue Book was published in 2007 (by the ISRM via the Turkish National Group) and contains the complete set of Suggested Methods from 1974 to 2006 inclusive. The papers in this most recent volume have been published during the last seven years in international journals, mainly in Rock Mechanics and Rock Engineering. They offer guidance for rock characterization procedures and laboratory and field testing and monitoring in rock engineering. These methods provide a definitive procedure for the identification, measurement and evaluation of one or more qualities, characteristics, or properties of rocks or rock systems that produces a test result.

  15. Research on definition of hard rock shear wave velocity of site for nuclear power plant

    International Nuclear Information System (INIS)

    Ding Zhenkun; Xia Zufeng

    2013-01-01

    Background: The definition of hard rock shear wave velocity is one of the most critical issues in the work of site selection. Purpose: To make a definition of hard rock site on which the model can be assumed as fixed-base condition, a series of research had been done. Several possible hard rock site soil models were developed. Methods: Shear wave velocity of hard rock had been assumed from 1100 m/s to 3200 m/s. For each case, free field analysis and soil structure analysis had been performed. And responses in soil and key nodes of structure were compared. Results: In free field analysis, responses of models that shear wave velocity below 2400 m/s decreased a lot. In SSI analysis, structure responses didn't change much when shear wave velocity was above 2400 m/s. Conclusions: 2400 m/s was the lowest shear wave velocity for hard rock site for fixed-base assumption. (authors)

  16. The Use of Gabbro Rock Armour in Rubble Mound Structures

    DEFF Research Database (Denmark)

    Beck, J. Blow; Burcharth, H. F.; Danielsen, S. W.

    2000-01-01

    Throughout several years Gabbro rocks have been used for various coast protective constructions and breakwaters at the North Sea Coast and in inner Danish waters. So far the use of Gabbro has been based solely on calculations from Shore Protection Manuals, i.e without model tests. Compared to ord...

  17. Optically stimulated luminescence dating of rock surfaces

    DEFF Research Database (Denmark)

    Sohbati, Reza

    There are many examples of rock surfaces, rock art and stone structures whose ages are of great importance to the understanding of various phenomena in geology, climatology and archaeology. Optically stimulated luminescence (OSL) dating is a well-established chronological tool that has successfully...... to include the effects of the environmental dose rate. By fitting the model to the dose-depth variation from a single clast, four events (two light exposures of different durations each followed by a burial period) in the history of a single cobble are identified and quantified. However, the use of model...

  18. The December 2008 Crammont rock avalanche, Mont Blanc massif area, Italy

    Directory of Open Access Journals (Sweden)

    P. Deline

    2011-12-01

    Full Text Available We describe a 0.5 Mm3 rock avalanche that occurred in 2008 in the western Alps and discuss possible roles of controlling factors in the context of current climate change. The source is located between 2410 m and 2653 m a.s.l. on Mont Crammont and is controlled by a densely fractured rock structure. The main part of the collapsed rock mass deposited at the foot of the rock wall. A smaller part travelled much farther, reaching horizontal and vertical travel distances of 3050 m and 1560 m, respectively. The mobility of the rock mass was enhanced by channelization and snow. The rock-avalanche volume was calculated by comparison of pre- and post-event DTMs, and geomechanical characterization of the detachment zone was extracted from LiDAR point cloud processing. Back analysis of the rock-avalanche runout suggests a two stage event.

    There was no previous rock avalanche activity from the Mont Crammont ridge during the Holocene. The 2008 rock avalanche may have resulted from permafrost degradation in the steep rock wall, as suggested by seepage water in the scar after the collapse in spite of negative air temperatures, and modelling of rock temperatures that indicate warm permafrost (T > −2 °C.

  19. Comparison of disposal concepts for rock salt and hard rock

    International Nuclear Information System (INIS)

    Papp, R.

    1998-01-01

    The study was carried out in the period 1994-1996. The goals were to prepare a draft on spent fuel disposal in hard rock and additionally a comparison with existing disposal concepts for rock salt. A cask for direct disposal of spent fuel and a repository for hard rock including a safeguards concept were conceptually designed. The results of the study confirm, that the early German decision to employ rock salt was reasonable. (orig.)

  20. Large-Scale True Triaxial Apparatus for Geophysical Studies in Fractured Rock

    KAUST Repository

    Garcia, A. V.

    2018-05-12

    The study of fractured rock masses in the laboratory remains challenging because of the large specimen sizes and bulky loading systems that are required. This article presents the design, structural analysis, and operation of a compact and self-reacting true triaxial device for fractured rock. The frame subjects a 50 cm by 50 cm by 50 cm fractured rock specimen to a maximum stress of 3 MPa along three independent axes. Concurrent measurements include long-wavelength P-wave propagation, passive acoustic emission monitoring, deformations, and thermal measurements. The device can accommodate diverse research, from rock mass properties and geophysical fractured rock characterizations, to coupled hydro-chemo-thermo-mechanical processes, drilling, and grouting. Preliminary wave propagation data gathered under isotropic and anisotropic stress conditions for an assembly of 4,000 rock blocks demonstrate the system’s versatility and provide unprecedented information related to long-wavelength propagation in fractured rock under various stress anisotropies.

  1. Large-Scale True Triaxial Apparatus for Geophysical Studies in Fractured Rock

    KAUST Repository

    Garcia, A. V.; Rached, R. M.; Santamarina, Carlos

    2018-01-01

    The study of fractured rock masses in the laboratory remains challenging because of the large specimen sizes and bulky loading systems that are required. This article presents the design, structural analysis, and operation of a compact and self-reacting true triaxial device for fractured rock. The frame subjects a 50 cm by 50 cm by 50 cm fractured rock specimen to a maximum stress of 3 MPa along three independent axes. Concurrent measurements include long-wavelength P-wave propagation, passive acoustic emission monitoring, deformations, and thermal measurements. The device can accommodate diverse research, from rock mass properties and geophysical fractured rock characterizations, to coupled hydro-chemo-thermo-mechanical processes, drilling, and grouting. Preliminary wave propagation data gathered under isotropic and anisotropic stress conditions for an assembly of 4,000 rock blocks demonstrate the system’s versatility and provide unprecedented information related to long-wavelength propagation in fractured rock under various stress anisotropies.

  2. Mechanism of Rock Burst Occurrence in Specially Thick Coal Seam with Rock Parting

    Science.gov (United States)

    Wang, Jian-chao; Jiang, Fu-xing; Meng, Xiang-jun; Wang, Xu-you; Zhu, Si-tao; Feng, Yu

    2016-05-01

    Specially thick coal seam with complex construction, such as rock parting and alternative soft and hard coal, is called specially thick coal seam with rock parting (STCSRP), which easily leads to rock burst during mining. Based on the stress distribution of rock parting zone, this study investigated the mechanism, engineering discriminant conditions, prevention methods, and risk evaluation method of rock burst occurrence in STCSRP through setting up a mechanical model. The main conclusions of this study are as follows. (1) When the mining face moves closer to the rock parting zone, the original non-uniform stress of the rock parting zone and the advancing stress of the mining face are combined to intensify gradually the shearing action of coal near the mining face. When the shearing action reaches a certain degree, rock burst easily occurs near the mining face. (2) Rock burst occurrence in STCSRP is positively associated with mining depth, advancing stress concentration factor of the mining face, thickness of rock parting, bursting liability of coal, thickness ratio of rock parting to coal seam, and difference of elastic modulus between rock parting and coal, whereas negatively associated with shear strength. (3) Technologies of large-diameter drilling, coal seam water injection, and deep hole blasting can reduce advancing stress concentration factor, thickness of rock parting, and difference of elastic modulus between rock parting and coal to lower the risk of rock burst in STCSRP. (4) The research result was applied to evaluate and control the risk of rock burst occurrence in STCSRP.

  3. Fault Rock Zones Characterisation - Final report. TRUE-1 Continuation Project

    International Nuclear Information System (INIS)

    Winberg, Anders

    2010-11-01

    At the conclusion of the TRUE-1 and TRUE Block Scale experimental programmes at the Aespoe Hard Rock Laboratory one remaining identified uncertainty was the in situ internal structure of conductive structures, and in particular the in situ material properties of unconsolidated fault gouge of such conductive structures. With the aim of reducing these uncertainties an experimental program has been conducted at depth in the Aespoe Hard Rock Laboratory. Four conductive structures in the immediate vicinity of the Aespoe tunnel were identified for further study. Following basic geometrical and geological modelling based on tunnel observations, geological/ mineralogical and hydrogeological investigations in four boreholes at each site, epoxy resin was injected in selected packed off borehole sections containing the structure. Following a sufficient time for curing of the epoxy, the injected borehole 72 mm sections were overcored with a 300 mm core barrel. Customised techniques were employed to section the core in the borehole and for its retrieval out of the borehole. Following basic geological mapping, selected overcores were sectioned and were subject to image analysis to assess the pore structure using a variety of different descriptive geometrical attributes. In addition, an attempt was made to infer the porosity of the fault rock (including fault gouge) using binary images. Since analysis has been made on multiple slices of impregnated rock it is also possible to crudely map the 3D variability of a given entity. It was furthermore identified that porosity estimates, which range from some 10-70% are, apart from being dependent on the penetration of the epoxy, dependent on the resolution of the given image, the size of the averaging window, and the porosity components contained therein. The obtained quantifications of porosity can therefore only be regarded as ball-park relative porosities of a complete fault rock zones. It does not, however, provide firm

  4. Fault Rock Zones Characterisation - Final report. TRUE-1 Continuation Project

    Energy Technology Data Exchange (ETDEWEB)

    Winberg, Anders (ed.) (Conterra AB (Sweden))

    2010-11-15

    At the conclusion of the TRUE-1 and TRUE Block Scale experimental programmes at the Aespoe Hard Rock Laboratory one remaining identified uncertainty was the in situ internal structure of conductive structures, and in particular the in situ material properties of unconsolidated fault gouge of such conductive structures. With the aim of reducing these uncertainties an experimental program has been conducted at depth in the Aespoe Hard Rock Laboratory. Four conductive structures in the immediate vicinity of the Aespoe tunnel were identified for further study. Following basic geometrical and geological modelling based on tunnel observations, geological/ mineralogical and hydrogeological investigations in four boreholes at each site, epoxy resin was injected in selected packed off borehole sections containing the structure. Following a sufficient time for curing of the epoxy, the injected borehole 72 mm sections were overcored with a 300 mm core barrel. Customised techniques were employed to section the core in the borehole and for its retrieval out of the borehole. Following basic geological mapping, selected overcores were sectioned and were subject to image analysis to assess the pore structure using a variety of different descriptive geometrical attributes. In addition, an attempt was made to infer the porosity of the fault rock (including fault gouge) using binary images. Since analysis has been made on multiple slices of impregnated rock it is also possible to crudely map the 3D variability of a given entity. It was furthermore identified that porosity estimates, which range from some 10-70% are, apart from being dependent on the penetration of the epoxy, dependent on the resolution of the given image, the size of the averaging window, and the porosity components contained therein. The obtained quantifications of porosity can therefore only be regarded as ball-park relative porosities of a complete fault rock zones. It does not, however, provide firm

  5. Rollerjaw Rock Crusher

    Science.gov (United States)

    Peters, Gregory; Brown, Kyle; Fuerstenau, Stephen

    2009-01-01

    The rollerjaw rock crusher melds the concepts of jaw crushing and roll crushing long employed in the mining and rock-crushing industries. Rollerjaw rock crushers have been proposed for inclusion in geological exploration missions on Mars, where they would be used to pulverize rock samples into powders in the tens of micrometer particle size range required for analysis by scientific instruments.

  6. Range sections as rock models for intensity rock scene segmentation

    CSIR Research Space (South Africa)

    Mkwelo, S

    2007-11-01

    Full Text Available This paper presents another approach to segmenting a scene of rocks on a conveyor belt for the purposes of measuring rock size. Rock size estimation instruments are used to monitor, optimize and control milling and crushing in the mining industry...

  7. Geological constraints for muon tomography: The world beyond standard rock

    Science.gov (United States)

    Lechmann, Alessandro; Mair, David; Ariga, Akitaka; Ariga, Tomoko; Ereditato, Antonio; Käser, Samuel; Nishiyama, Ryuichi; Scampoli, Paola; Vladymyrov, Mykhailo; Schlunegger, Fritz

    2017-04-01

    In present day muon tomography practice, one often encounters an experimental setup in which muons propagate several tens to a few hundreds of meters through a material to the detector. The goal of such an undertaking is usually centred on an attempt to make inferences from the measured muon flux to an anticipated subsurface structure. This can either be an underground interface geometry or a spatial material distribution. Inferences in this direction have until now mostly been done, thereby using the so called "standard rock" approximation. This includes a set of empirically determined parameters from several rocks found in the vicinity of physicist's laboratories. While this approach is reasonable to account for the effects of the tens of meters of soil/rock around a particle accelerator, we show, that for material thicknesses beyond that dimension, the elementary composition of the material (average atomic weight and atomic number) has a noticeable effect on the measured muon flux. Accordingly, the consecutive use of this approximation could potentially lead into a serious model bias, which in turn, might invalidate any tomographic inference, that base on this standard rock approximation. The parameters for standard rock are naturally close to a granitic (SiO2-rich) composition and thus can be safely used in such environments. As geophysical surveys are not restricted to any particular lithology, we investigated the effect of alternative rock compositions (carbonatic, basaltic and even ultramafic) and consequentially prefer to replace the standard rock approach with a dedicated geological investigation. Structural field data and laboratory measurements of density (He-Pycnometer) and composition (XRD) can be merged into an integrative geological model that can be used as an a priori constraint for the rock parameters of interest (density & composition) in the geophysical inversion. Modelling results show that when facing a non-granitic lithology the measured muon

  8. Mechanical and Thermophysical Properties of Cubic Rock-Salt AlN Under High Pressure

    Science.gov (United States)

    Lebga, Noudjoud; Daoud, Salah; Sun, Xiao-Wei; Bioud, Nadhira; Latreche, Abdelhakim

    2018-03-01

    Density functional theory, density functional perturbation theory, and the Debye model have been used to investigate the structural, elastic, sound velocity, and thermodynamic properties of AlN with cubic rock-salt structure under high pressure, yielding the equilibrium structural parameters, equation of state, and elastic constants of this interesting material. The isotropic shear modulus, Pugh ratio, and Poisson's ratio were also investigated carefully. In addition, the longitudinal, transverse, and average elastic wave velocities, phonon contribution to the thermal conductivity, and interesting thermodynamic properties were predicted and analyzed in detail. The results demonstrate that the behavior of the elastic wave velocities under increasing hydrostatic pressure explains the hardening of the corresponding phonons. Based on the elastic stability criteria under pressure, it is found that AlN with cubic rock-salt structure is mechanically stable, even at pressures up to 100 GPa. Analysis of the Pugh ratio and Poisson's ratio revealed that AlN with cubic rock-salt structure behaves in brittle manner.

  9. Fluids in crustal deformation: Fluid flow, fluid-rock interactions, rheology, melting and resources

    Science.gov (United States)

    Lacombe, Olivier; Rolland, Yann

    2016-11-01

    Fluids exert a first-order control on the structural, petrological and rheological evolution of the continental crust. Fluids interact with rocks from the earliest stages of sedimentation and diagenesis in basins until these rocks are deformed and/or buried and metamorphosed in orogens, then possibly exhumed. Fluid-rock interactions lead to the evolution of rock physical properties and rock strength. Fractures and faults are preferred pathways for fluids, and in turn physical and chemical interactions between fluid flow and tectonic structures, such as fault zones, strongly influence the mechanical behaviour of the crust at different space and time scales. Fluid (over)pressure is associated with a variety of geological phenomena, such as seismic cycle in various P-T conditions, hydrofracturing (including formation of sub-horizontal, bedding-parallel veins), fault (re)activation or gravitational sliding of rocks, among others. Fluid (over)pressure is a governing factor for the evolution of permeability and porosity of rocks and controls the generation, maturation and migration of economic fluids like hydrocarbons or ore forming hydrothermal fluids, and is therefore a key parameter in reservoir studies and basin modeling. Fluids may also help the crust partially melt, and in turn the resulting melt may dramatically change the rheology of the crust.

  10. Geohydromechanical Processes in the Excavation Damaged Zone in Crystalline Rock, Rock Salt, and Indurated and Plastic Clays

    International Nuclear Information System (INIS)

    Tsang, Chin-Fu; Bernier, Frederic; Davies, Christophe

    2004-01-01

    The creation of an excavation disturbed zone or excavation damaged zone is expected around all man-made openings in geologic formations. Macro- and micro-fracturing, and in general a redistribution of in situ stresses and rearrangement of rock structures, will occur in this zone, resulting in drastic changes of permeability to flow, mainly through the fractures and cracks induced by excavation. Such an EDZ may have significant implications for the operation and long-term performance of an underground nuclear waste repository. Various issues of concern need to be evaluated, such as processes creating fractures in the excavation damaged zone, the degree of permeability increase, and the potential for sealing or healing (with permeability reduction) in the zone. In recent years, efforts along these lines have been made for a potential repository in four rock types-crystalline rock, salt, indurated clay, and plastic clay-and these efforts have involved field, laboratory, and theoretical studies. The present work involves a synthesis of the ideas and issues that emerged from presentations and discussions on EDZ in these four rock types at a CLUSTER Conference and Workshop held in Luxembourg in November, 2003. First, definitions of excavation disturbed and excavation damaged zones are proposed. Then, an approach is suggested for the synthesis and intercomparison of geohydromechanical processes in the EDZ for the four rock types (crystalline rock, salt, indurated clay, and plastic clay). Comparison tables of relevant processes, associated factors, and modeling and testing techniques are developed. A discussion of the general state-of-the-art and outstanding issues are also presented. A substantial bibliography of relevant papers on the subject is supplied at the end of the paper

  11. A diffuse radar scattering model from Martian surface rocks

    Science.gov (United States)

    Calvin, W. M.; Jakosky, B. M.; Christensen, P. R.

    1987-01-01

    Remote sensing of Mars has been done with a variety of instrumentation at various wavelengths. Many of these data sets can be reconciled with a surface model of bonded fines (or duricrust) which varies widely across the surface and a surface rock distribution which varies less so. A surface rock distribution map from -60 to +60 deg latitude has been generated by Christensen. Our objective is to model the diffuse component of radar reflection based on this surface distribution of rocks. The diffuse, rather than specular, scattering is modeled because the diffuse component arises due to scattering from rocks with sizes on the order of the wavelength of the radar beam. Scattering for radio waves of 12.5 cm is then indicative of the meter scale and smaller structure of the surface. The specular term is indicative of large scale surface undulations and should not be causally related to other surface physical properties. A simplified model of diffuse scattering is described along with two rock distribution models. The results of applying the models to a planet of uniform fractional rock coverage with values ranging from 5 to 20% are discussed.

  12. Macroscopic Rock Texture Image Classification Using a Hierarchical Neuro-Fuzzy Class Method

    Directory of Open Access Journals (Sweden)

    Laercio B. Gonçalves

    2010-01-01

    Full Text Available We used a Hierarchical Neuro-Fuzzy Class Method based on binary space partitioning (NFHB-Class Method for macroscopic rock texture classification. The relevance of this study is in helping Geologists in the diagnosis and planning of oil reservoir exploration. The proposed method is capable of generating its own decision structure, with automatic extraction of fuzzy rules. These rules are linguistically interpretable, thus explaining the obtained data structure. The presented image classification for macroscopic rocks is based on texture descriptors, such as spatial variation coefficient, Hurst coefficient, entropy, and cooccurrence matrix. Four rock classes have been evaluated by the NFHB-Class Method: gneiss (two subclasses, basalt (four subclasses, diabase (five subclasses, and rhyolite (five subclasses. These four rock classes are of great interest in the evaluation of oil boreholes, which is considered a complex task by geologists. We present a computer method to solve this problem. In order to evaluate system performance, we used 50 RGB images for each rock classes and subclasses, thus producing a total of 800 images. For all rock classes, the NFHB-Class Method achieved a percentage of correct hits over 73%. The proposed method converged for all tests presented in the case study.

  13. Multivariate statistics application in development of blast fragmentation charts for different rock formations in quarries

    Directory of Open Access Journals (Sweden)

    Birol Elevli

    2012-12-01

    Full Text Available Rock fragmentation is considered to be one of the most important aspects of quarrying because of its direct effect on the costsof drilling, which include blasting, loading, hauling and crushing. Thus, it is essential to consider fragmentation size in blasting design.Fragmentation depends on many variables, such as rock properties, geological structures, and blasting parameters. Although empiricalmodels for the estimation of the size distribution of rock fragmentation have been developed by considering these parameters,no complete empirical prediction model for fragmentation exists since rock properties and geological structures vary from site to site.However, these models regard rock properties as constant. In this study, a step–wise multiple linear regression analysis has beencarried out to determine the degree of dominance of various influencing parameters on fragmentation and to develop a fragmentationprediction model. The results showed that the rock mass properties, burden width and specific charge are the main parameters affectingfragmentation. The relations among those parameters were used to develop guideline charts to determine blast layouts for desiredfragmentation on the basis of rock characteristics.

  14. Fluid and rock interaction in permeable volcanic rock

    International Nuclear Information System (INIS)

    Lindley, J.I.

    1985-01-01

    Four types of interrelated changes -geochemical, mineralogic, isotopic, and physical - occur in Oligocene volcanic units of the Mogollon-Datil volcanic field, New Mexico. These changes resulted from the operation of a geothermal system that, through fluid-rock interaction, affected 5 rhyolite ash-flow tuffs and an intercalated basaltic andesite lava flow causing a potassium metasomatism type of alteration. (1) Previous studies have shown enrichment of rocks in K 2 O as much as 130% of their original values at the expense of Na 2 O and CaO with an accompanying increase in Rb and decreases in MgO and Sr. (2) X-ray diffraction results of this study show that phenocrystic plagioclase and groundmass feldspar have been replaced with pure potassium feldspar and quartz in altered rock. Phenocrystic potassium feldspar, biotite, and quartz are unaffected. Pyroxene in basaltic andesite is replaced by iron oxide. (3) delta 18 O increases for rhyolitic units from values of 8-10 permil, typical of unaltered rock, to 13-15 permil, typical of altered rock. Basaltic andesite, however, shows opposite behavior with a delta 18 of 9 permil in unaltered rock and 6 permit in altered. (4) Alteration results in a density decrease. SEM revealed that replacement of plagioclase by fine-grained quartz and potassium feldspar is not a volume for volume replacement. Secondary porosity is created in the volcanics by the chaotic arrangement of secondary crystals

  15. Evaluation of early Archean volcaniclastic and volcanic flow rocks as possible sites for carbonaceous fossil microbes.

    Science.gov (United States)

    Walsh, Maud M

    2004-01-01

    Sedimentary rocks have traditionally been the focus of the search for Archean microfossils; the Earth's oldest fossil bacteria are associated with carbonaceous matter in sedimentary cherts in greenstone belts in the eastern Pilbara block of Western Australia and Barberton greenstone belt of South Africa. Reports of possible fossils in a martian meteorite composed of igneous rock and the discovery of modern bacteria associated with basalts have stimulated a new look at Archean volcanic rocks as possible sites for fossil microbes. This study examines silicified volcaniclastic rocks, near-surface altered volcanic flow rocks, and associated stromatolite- like structures from the Archean Barberton greenstone belt to evaluate their potential for the preservation of carbonaceous fossils. Detrital carbonaceous particles are widely admixed with current-deposited debris. Carbonaceous matter is also present in altered volcanic flow rocks as sparse particles in silica veins that appear to be fed by overlying carbonaceous chert layers. Neither microfossils nor mat-like material was identified in the altered volcanic rocks or adjacent stromatolite-like structures. Ancient volcanic flow and volcaniclastic rocks are not promising sites for carbonaceous fossil preservation.

  16. Estimation of strong motions on free rock surface. Identification of soil structures and strong motions on free rock surface in Kashiwazaki-Kariwa nuclear power plant during the 2007 Niigataken Chuetsu-oki earthquake

    International Nuclear Information System (INIS)

    Saguchi, Koichiro; Masaki, Kazuaki; Irikura, Kojiro

    2009-01-01

    Very strong ground motions (maximum acceleration 993 cm/s 2 in the borehole seismometer point of -255m in depth) were observed in the Kashiwazaki Kariwa Nuclear Power Plant during the Niigataken Chuetsu-oki Earthquake on July 16, 2007. In this study, we tried to develop new method, which can simulate waveforms on free rock surface by using the bore hole records. We identified the underground structure model at the Service Hall from aftershock records observed in vertical array, using the simulated annealing method (Ingber(1989)). Based on numerical experiments it is identified that S-wave velocity and Q values of individual layers are inverted very well. Strong motion records of main shock observed by the bore hole seismometers were simulated by using one-dimensional multiple reflection method. In this study, non-linear effect is considered by introducing non-linear coefficient c(f) for under coming wave from surface. The maximum acceleration and phase characteristics in simulated waveforms are similar to the observed one. It means that our method is useful for simulate strong motion in non-linear region. Finally, strong motions on the free rock surface at the Service Hall during the main shock are simulated. The maximum acceleration of EW component on free rock surface is estimated to be 1,207 cm/s 2 . (author)

  17. Disc cutter wear and rock texture in hard rock TBM tunneling

    International Nuclear Information System (INIS)

    Koizumi, Yu; Tsusaka, Kimikazu; Tanimoto, Chikaosa; Nakagawa, Shigeo; Fujita, Naoya

    2008-01-01

    Disc cutter wear in TBM tunneling is caused by initial fragmentation of a solid rock face (the primary fragmentation) and fragmentation of residual rock pieces between a cutterhead and the face (the secondary fragmentation). In two projects through sedimentary and granitic rocks, the authors investigated the relationships between the rate of cutter wear caused by the primary fragmentation, point load index and the grain size and contents of abrasive minerals. As a result, it was found that the tensile strength and the mineral contents of rocks significantly influenced the cutter wear in both projects and thus it is necessary to take into account of rock type. (author)

  18. Precambrian evolution and the rock record

    Science.gov (United States)

    Awramik, S.

    1985-01-01

    The Precambrian time which refers to geological time prior to the first appearance of animals with mineralized hard parts was investigated. Best estimates for this event are around 570 million years ago. Because the rock record begins some 3,800 million years ago the Precambrian encompasses about 84% of geologic time. The fossil record for this immense span of time is dominated by prokaryotes and the sedimentary structures produced by them. The first fossil remains that are considered eukaryotic are found in 1,000 million year old rocks. The first animals may be as old as 700 million years. The fossil records of the first 84% of the Earth's history are collected and described.

  19. Frictional sliding tests on combined coal-rock samples

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2014-06-01

    Full Text Available A test system was developed to understand the sliding mechanism of coal-rock structure. The test system was composed by a double-shear testing model and an acousto-optic monitoring system in association with a digital camera and an acoustic emission (AE instrument. The tests can simulate the movement of activated faults and the sliding in coal-rock structure. In this regard, instable sliding conditions of coal-rock samples, sliding types under different conditions, displacement evolution law, and AE characteristics during sliding process were investigated. Several sliding types were monitored in the tests, including unstable continuous sliding, unstable discontinuous sliding, and stable sliding. The sliding types have close relation with the axial loads and loading rates. Larger axial load and smaller loading rate mean that unstable sliding is less likely to occur. The peak shear stress was positively correlated with the axial load when sliding occurred, whereas the displacement induced by unstable sliding was uncorrelated with the axial load. A large number of AE events occurred before sliding, and the AE rate decreased after stable sliding. The results show that the tests can well simulate the process of structural instability in a coal bump, and are helpful in the understanding of fault activation and the physical processes during squeezing process of roof and floor.

  20. Ecologically justified regulatory provisions for riverine hydroelectric power plants and minimum instream flow requirements in diverted streams; Oekologisch begruendete, dynamische Mindestwasserregelungen bei Ausleitungskraftwerken

    Energy Technology Data Exchange (ETDEWEB)

    Jorde, K.

    1997-12-31

    The study was intended to develop a model versatile enough to permit quantification of various water demand scenarios in connection with operation of riverine hydroelectric power plants. Specific emphasis was to be placed on defining the minimum instream flow to be maintained in river segments because of the elementary significance to flowing water biocinoses. Based on fictitious minimum water requirements, various scenarious were simulated for flow regimes depending on power plant operation, so as to establish a system for comparative analysis and evaluation of resulting economic effects on power plant efficiency on the one hand, and the ecologic effects on the aquatic habitat. The information derived was to serve as a basis for decision-making for regulatory purposes. For this study, the temporal and spatial variability of the flow regime at the river bed in a river segment was examined for the first time. Based on this information, complemented by information obtained from habitat simulations, a method was derived for determination of ecologic requirements and their incorporation into regulatory water management provisions. The field measurements were carried out with the FST hemisphere as a proven and most efficient and reliable method of assessing flow regimes at river beds. Evaluation of the measured instream flow data characterising three morphologically different segments of diverted rivers was done with the CASIMIR computer code. The ASS models derived were used for comparative assessment of existing regulatory provisions and recommended amendments determining required minimum instream flow in diverted rivers. The requirements were defined taking as a basis data obtained for three different years. (orig./CB) [Deutsch] Ziel der Arbeit war die Entwicklung eines Modellverfahrens, das flexibel die Quantifizierung unterschiedlicher Nutzansprueche an Laufwasserkraftanlagen ermoeglicht. Insbesondere der Erhalt einer gewissen Dynamik, die fuer

  1. Ecologically justified regulatory provisions for riverine hydroelectric power plants and minimum instream flow requirements in diverted streams; Oekologisch begruendete, dynamische Mindestwasserregelungen bei Ausleitungskraftwerken

    Energy Technology Data Exchange (ETDEWEB)

    Jorde, K

    1998-12-31

    The study was intended to develop a model versatile enough to permit quantification of various water demand scenarios in connection with operation of riverine hydroelectric power plants. Specific emphasis was to be placed on defining the minimum instream flow to be maintained in river segments because of the elementary significance to flowing water biocinoses. Based on fictitious minimum water requirements, various scenarious were simulated for flow regimes depending on power plant operation, so as to establish a system for comparative analysis and evaluation of resulting economic effects on power plant efficiency on the one hand, and the ecologic effects on the aquatic habitat. The information derived was to serve as a basis for decision-making for regulatory purposes. For this study, the temporal and spatial variability of the flow regime at the river bed in a river segment was examined for the first time. Based on this information, complemented by information obtained from habitat simulations, a method was derived for determination of ecologic requirements and their incorporation into regulatory water management provisions. The field measurements were carried out with the FST hemisphere as a proven and most efficient and reliable method of assessing flow regimes at river beds. Evaluation of the measured instream flow data characterising three morphologically different segments of diverted rivers was done with the CASIMIR computer code. The ASS models derived were used for comparative assessment of existing regulatory provisions and recommended amendments determining required minimum instream flow in diverted rivers. The requirements were defined taking as a basis data obtained for three different years. (orig./CB) [Deutsch] Ziel der Arbeit war die Entwicklung eines Modellverfahrens, das flexibel die Quantifizierung unterschiedlicher Nutzansprueche an Laufwasserkraftanlagen ermoeglicht. Insbesondere der Erhalt einer gewissen Dynamik, die fuer

  2. Rocks Can Wow? Yes, Rocks Can Wow!

    Science.gov (United States)

    Hardman, Sally; Luke, Sue

    2016-01-01

    Rocks and fossils appear in the National Curriculum of England science programmes of study for children in year 3 (ages 7-8). A frequently asked question is "How do you make the classification of rocks engaging?" In response to this request from a school, a set of interactive activities was designed and organised by tutors and students…

  3. Relating rock avalanche morphology to emplacement processes

    Science.gov (United States)

    Dufresne, Anja; Prager, Christoph; Bösmeier, Annette

    2015-04-01

    The morphology, structure and sedimentological characteristics of rock avalanche deposits reflect both internal emplacement processes and external influences, such as runout path characteristics. The latter is mainly predisposed by topography, substrate types, and hydrogeological conditions. Additionally, the geological setting at the source slope controls, e.g. the spatial distribution of accumulated lithologies and hence material property-related changes in morphology, or the maximum clast size and amount of fines of different lithological units. The Holocene Tschirgant rock avalanche (Tyrol, Austria) resulted from failure of an intensely deformed carbonate rock mass on the southeast face of a 2,370-m-high mountain ridge. The initially sliding rock mass rapidly fragmented as it moved towards the floor of the Inn River valley. Part of the 200-250 x 106 m3 (Patzelt 2012) rock avalanche debris collided with and moved around an opposing bedrock ridge and flowed into the Ötz valley, reaching up to 6.3 km from source. Where the Tschirgant rock avalanche spread freely it formed longitudinal ridges aligned along motion direction as well as smaller hummocks. Encountering high topography, it left runup ridges, fallback patterns (i.e. secondary collapse), and compressional morphology (successively elevated, transverse ridges). Further evidence for the mechanical landslide behaviour is given by large volumes of mobilized valley-fill sediments (polymict gravels and sands). These sediments indicate both shearing and compressional faulting within the rock avalanche mass (forming their own morphological units through, e.g. in situ bulldozing or as distinctly different hummocky terrain), but also indicate extension of the spreading landslide mass (i.e. intercalated/injected gravels encountered mainly in morphological depressions between hummocks). Further influences on its morphology are given by the different lithological units. E.g. the transition from massive dolomite

  4. The geology and mechanics of formation of the Fort Rock Dome, Yavapai County, Arizona

    Science.gov (United States)

    Fuis, Gary S.

    1996-01-01

    The Fort Rock Dome, a craterlike structure in northern Arizona, is the erosional product of a circular domal uplift associated with a Precambrian shear zone exposed within the crater and with Tertiary volcanism. A section of Precambrian to Quaternary rocks is described, and two Tertiary units, the Crater Pasture Formation and the Fort Rock Creek Rhyodacite, are named. A mathematical model of the doming process is developed that is consistent with the history of the Fort Rock Dome.

  5. Anisotropy effect on strengths of metamorphic rocks

    Directory of Open Access Journals (Sweden)

    Ahmet Özbek

    2018-02-01

    Full Text Available This paper aims to study the effect of anisotropy on strengths of several metamorphic rocks of southern (Çine submassif of Menderes metamorphic massif in southwest Turkey. Four different metamorphic rocks including foliated phyllite, schist, gneiss and marble (calcschist were selected and examined. Discontinuity surveys were made along lines for each rock and evaluated with DIPS program. L-type Schmidt hammer was applied in the directions parallel and perpendicular to foliation during the field study. Several hand samples and rock blocks were collected during the field study for measurements of dry and saturated densities, dry and saturated unit weights and porosity, and for petrographic analysis and strength determination in laboratory. L- and N-type Schmidt hammers were applied in the directions perpendicular (anisotropy angle of 0° and parallel (anisotropy angle of 90° to the foliation on selected blocks of phyllite, schist, gneiss and marble (calcschist. The phyllite and schist have higher porosity and lower density values than the other rocks. However, coarse crystalline gneiss and marble (calcschist have higher rebound values and strengths, and they are classified as strong–very strong rocks. Generally, the rebound values in the direction perpendicular to the foliation are slightly higher than that in the direction parallel to foliation. Rebound values of N-type Schmidt hammer are higher than the L-type values except for phyllite. Sometimes, the rebound values of laboratory and field applications gave different results. This may result from variable local conditions such as minerals differentiation, discontinuities, water content, weathering degree and thickness of foliated structure.

  6. Folding and Fracturing of Rocks: the background

    Science.gov (United States)

    Ramsay, John G.

    2017-04-01

    This book was generated by structural geology teaching classes at Imperial College. I was appointed lecturer during 1957 and worked together with Dr Gilbert Wilson teaching basic structural geology at B.Sc level. I became convinced that the subject, being essentially based on geometric field observations, required a firm mathematical basis for its future development. In particular it seemed to me to require a very sound understanding of stress and strain. My field experience suggested that a knowledge of two- and three-demensional strain was critical in understanding natural tectonic processes. I found a rich confirmation for this in early publications of deformed fossils, oolitic limestones and spotted slates made by several geologists around the beginning of the 20th century (Sorby, Philips, Haughton, Harker) often using surprisingly sophisticated mathematical methods. These methods were discussed and elaborated in Folding and Fracturing of Rocks in a practical way. The geometric features of folds were related to folding mechanisms and the fold related small scale structures such as cleavage, schistosity and lineation explained in terms of rock strain. My work in the Scottish Highlands had shown just how repeated fold superposition could produce very complex geometric features, while further work in other localities suggested that such geometric complications are common in many orogenic zones. From the development of structural geological studies over the past decades it seems that the readers of this book have found many of the ideas set out are still of practical application. The mapping of these outcrop-scale structures should be emphasised in all field studies because they can be seen as ''fingerprints'' of regional scale tectonic processes. My own understanding of structural geology has been inspired by field work and I am of the opinion that future progress in understanding will be likewise based on careful observation and measurement of the features of

  7. Rock Fracture Toughness Study Under Mixed Mode I/III Loading

    Science.gov (United States)

    Aliha, M. R. M.; Bahmani, A.

    2017-07-01

    Fracture growth in underground rock structures occurs under complex stress states, which typically include the in- and out-of-plane sliding deformation of jointed rock masses before catastrophic failure. However, the lack of a comprehensive theoretical and experimental fracture toughness study for rocks under contributions of out-of plane deformations (i.e. mode III) is one of the shortcomings of this field. Therefore, in this research the mixed mode I/III fracture toughness of a typical rock material is investigated experimentally by means of a novel cracked disc specimen subjected to bend loading. It was shown that the specimen can provide full combinations of modes I and III and consequently a complete set of mixed mode I/III fracture toughness data were determined for the tested marble rock. By moving from pure mode I towards pure mode III, fracture load was increased; however, the corresponding fracture toughness value became smaller. The obtained experimental fracture toughness results were finally predicted using theoretical and empirical fracture models.

  8. Characterization of Geologic Structures and Host Rock Properties Relevant to the Hydrogeology of the Standard Mine in Elk Basin, Gunnison County, Colorado

    Science.gov (United States)

    Caine, Jonathan S.; Manning, Andrew H.; Berger, Byron R.; Kremer, Yannick; Guzman, Mario A.; Eberl, Dennis D.; Schuller, Kathryn

    2010-01-01

    The Standard Mine Superfund Site is a source of mine drainage and associated heavy metal contamination of surface and groundwaters. The site contains Tertiary polymetallic quartz veins and fault zones that host precious and base metal sulfide mineralization common in Colorado. To assist the U.S. Environmental Protection Agency in its effort to remediate mine-related contamination, we characterized geologic structures, host rocks, and their potential hydraulic properties to better understand the sources of contaminants and the local hydrogeology. Real time kinematic and handheld global positioning systems were used to locate and map precisely the geometry of the surface traces of structures and mine-related features, such as portals. New reconnaissance geologic mapping, field and x-ray diffraction mineralogy, rock sample collection, thin-section analysis, and elemental geochemical analysis were completed to characterize hydrothermal alteration, mineralization, and subsequent leaching of metallic phases. Surface and subsurface observations, fault vein and fracture network characterization, borehole geophysical logging, and mercury injection capillary entry pressure data were used to document potential controls on the hydrologic system.

  9. Rock stress investigations

    International Nuclear Information System (INIS)

    Pahl, A.; Heusermann, St.; Braeuer, V.; Gloeggler, W.

    1989-04-01

    On the research project 'Rock Stress Mesurements' the BGR has developed and tested several methods for use in boreholes at a depth of 200 m. Indirect stress measurements using overcoring methods with BGR-probes and CSIR-triaxial cells as well as direct stress measurements using the hydraulic-fracturing method were made. To determine in-situ rock deformation behavior borehole deformation tests, using a BGR-dilatometer, were performed. Two types of the BGR-probe were applied: a four-component-probe to determine horizontal stresses and a five-component-probe to determine a quasi three-dimensional stress field. The first time a computer for data processing was installed in the borehole together with the BGR-probe. Laboratory tests on low cylinders were made to study the stress-deformation behavior. To validate and to interprete the measurement results some test methods were modelled using the finite-element method. The dilatometer-tests yielded high values of Young's modulus, whereas laboratory tests showed lower values with a distinct deformation anisotropy. Stress measurements with the BGR-probe yielded horizontal stresses being higher than the theoretical overburden pressure. These results are comparable to the results of the hydraulic fracturing tests, whereas stresses obtained with CSIR-triaxial cells are lower. The detailed geological mapping of the borehole indicated relationships between stress and geology. With regard to borehole depth different zones of rock structure joint frequency, joint orientation, and orientation of microfissures as well as stress magnitude, stress direction, and degree of deformation anisotropy could be distinguished. (author) 4 tabs., 76 figs., 31 refs

  10. Quantitative rock-fall hazard and risk assessment for Yosemite Valley, California

    Science.gov (United States)

    Stock, G. M.; Luco, N.; Collins, B. D.; Harp, E.; Reichenbach, P.; Frankel, K. L.

    2011-12-01

    Rock falls are a considerable hazard in Yosemite Valley, California with more than 835 rock falls and other slope movements documented since 1857. Thus, rock falls pose potentially significant risk to the nearly four million annual visitors to Yosemite National Park. Building on earlier hazard assessment work by the U.S. Geological Survey, we performed a quantitative rock-fall hazard and risk assessment for Yosemite Valley. This work was aided by several new data sets, including precise Geographic Information System (GIS) maps of rock-fall deposits, airborne and terrestrial LiDAR-based point cloud data and digital elevation models, and numerical ages of talus deposits. Using Global Position Systems (GPS), we mapped the positions of over 500 boulders on the valley floor and measured their distance relative to the mapped base of talus. Statistical analyses of these data yielded an initial hazard zone that is based on the 90th percentile distance of rock-fall boulders beyond the talus edge. This distance was subsequently scaled (either inward or outward from the 90th percentile line) based on rock-fall frequency information derived from a combination of cosmogenic beryllium-10 exposure dating of boulders beyond the edge of the talus, and computer model simulations of rock-fall runout. The scaled distances provide the basis for a new hazard zone on the floor of Yosemite Valley. Once this zone was delineated, we assembled visitor, employee, and resident use data for each structure within the hazard zone to quantitatively assess risk exposure. Our results identify areas within the new hazard zone that may warrant more detailed study, for example rock-fall susceptibility, which can be assessed through examination of high-resolution photographs, structural measurements on the cliffs, and empirical calculations derived from LiDAR point cloud data. This hazard and risk information is used to inform placement of existing and potential future infrastructure in Yosemite Valley.

  11. Rock Physics

    DEFF Research Database (Denmark)

    Fabricius, Ida Lykke

    2017-01-01

    Rock physics is the discipline linking petrophysical properties as derived from borehole data to surface based geophysical exploration data. It can involve interpretation of both elastic wave propagation and electrical conductivity, but in this chapter focus is on elasticity. Rock physics is based...... on continuum mechanics, and the theory of elasticity developed for statics becomes the key to petrophysical interpretation of velocity of elastic waves. In practice, rock physics involves interpretation of well logs including vertical seismic profiling (VSP) and analysis of core samples. The results...

  12. Mineral and rock chemistry of Mata da Corda Kamafugitic Rocks (Minas Gerais State, Brazil)

    International Nuclear Information System (INIS)

    Albuquerque Sgarbi, Patricia B. de; Valenca, Joel G.

    1995-01-01

    The volcanic rocks of the Mata da Corda Formation (Upper Cretaceous) in Minas Gerais, Brazil, are mafic potassic to ultra potassic rocks of kamafugitic affinity containing essentially clinopyroxenes, perovskite, magnetite and occasionally olivine, phlogopite, melilite pseudomorphs and apatite. The felsic phases are kalsilite and/or leucite pseudomorphs. The rocks are classified as mafitites, leucitites and kalsilitites. The analysis of the available data of the rocks studied, based on the relevant aspects of the main proposals for the classification of alkaline mafic to ultramafic potassic rocks leads to the conclusion that Sahama's (1974) proposal to divide potassium rich alkaline rocks in two large families is the one to which the Mata da Corda rocks adapt best. According to this and the data in the literature on the mineralogy and mineral and rock chemistries of the other similar occurrences, these rocks may be interpreted as alkaline potassic to ultra potassic rocks of hamafugitic affinity. 11 figs., 5 tabs

  13. In situ determination of a rock mass modulus using a high resolution tiltmeter

    Energy Technology Data Exchange (ETDEWEB)

    Saleh, B.; Husein Malkawi, A.I. [University of Jordan, Amman (Jordan); Blum, P.A. [Universite Pierre et Marie Curie, 75 - Paris (France)

    1996-04-01

    A very sensitive, compact tiltmeter made of melted silica, developed for the measurement of small deformations of various civil engineering structures, was described. The instrument is capable of giving a continuous record and was used to establish a new approach to directly evaluating the in situ average elastic rock mass modulus. Such information is important in decision making during the design stages of large civil engineering works, such as dams, nuclear plant facilities, and underground structures. Five tiltmeters were installed on the facades of the Louvre in Paris to study the deformation induced by internal structural work and by the impact of the Paris metro traffic movement. The data was used to determine displacement using the Boussinesq equation. Results were consistent with typical elastic rock-mass modulus for the rock found in the museum`s foundations. 13 refs., 1 tab., 10 figs.

  14. Stability of Large Parallel Tunnels Excavated in Weak Rocks: A Case Study

    Science.gov (United States)

    Ding, Xiuli; Weng, Yonghong; Zhang, Yuting; Xu, Tangjin; Wang, Tuanle; Rao, Zhiwen; Qi, Zufang

    2017-09-01

    Diversion tunnels are important structures for hydropower projects but are always placed in locations with less favorable geological conditions than those in which other structures are placed. Because diversion tunnels are usually large and closely spaced, the rock pillar between adjacent tunnels in weak rocks is affected on both sides, and conventional support measures may not be adequate to achieve the required stability. Thus, appropriate reinforcement support measures are needed, and the design philosophy regarding large parallel tunnels in weak rocks should be updated. This paper reports a recent case in which two large parallel diversion tunnels are excavated. The rock masses are thin- to ultra-thin-layered strata coated with phyllitic films, which significantly decrease the soundness and strength of the strata and weaken the rocks. The behaviors of the surrounding rock masses under original (and conventional) support measures are detailed in terms of rock mass deformation, anchor bolt stress, and the extent of the excavation disturbed zone (EDZ), as obtained from safety monitoring and field testing. In situ observed phenomena and their interpretation are also included. The sidewall deformations exhibit significant time-dependent characteristics, and large magnitudes are recorded. The stresses in the anchor bolts are small, but the extents of the EDZs are large. The stability condition under the original support measures is evaluated as poor. To enhance rock mass stability, attempts are made to reinforce support design and improve safety monitoring programs. The main feature of these attempts is the use of prestressed cables that run through the rock pillar between the parallel tunnels. The efficacy of reinforcement support measures is verified by further safety monitoring data and field test results. Numerical analysis is constantly performed during the construction process to provide a useful reference for decision making. The calculated deformations are in

  15. Site investigations: Strategy for rock mechanics site descriptive model

    International Nuclear Information System (INIS)

    Andersson, Johan; Christiansson, Rolf; Hudson, John

    2002-05-01

    As a part of the planning work for the Site Investigations, SKB has developed a Rock Mechanics Site Descriptive Modelling Strategy. Similar strategies are being developed for other disciplines. The objective of the strategy is that it should guide the practical implementation of evaluating site specific data during the Site Investigations. It is also understood that further development may be needed. This methodology enables the crystalline rock mass to be characterised in terms of the quality at different sites, for considering rock engineering constructability, and for providing the input to numerical models and performance assessment calculations. The model describes the initial stresses and the distribution of deformation and strength properties of the intact rock, of fractures and fracture zones, and of the rock mass. The rock mass mechanical properties are estimated by empirical relations and by numerical simulations. The methodology is based on estimation of mechanical properties using both empirical and heroretical/numerical approaches; and estimation of in situ rock stress using judgement and numerical modelling, including the influence of fracture zones. These approaches are initially used separately, and then combined to produce the required characterisation estimates. The methodology was evaluated with a Test Case at the Aespoe Hard Rock Laboratory in Sweden. The quality control aspects are an important feature of the methodology: these include Protocols to ensure the structure and coherence of the procedures used, regular meetings to enhance communication, feedback from internal and external reviewing, plus the recording of an audit trail of the development steps and decisions made. The strategy will be reviewed and, if required, updated as appropriate

  16. Site investigations: Strategy for rock mechanics site descriptive model

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Johan [JA Streamflow AB, Aelvsjoe (Sweden); Christiansson, Rolf [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Hudson, John [Rock Engineering Consultants, Welwyn Garden City (United Kingdom)

    2002-05-01

    As a part of the planning work for the Site Investigations, SKB has developed a Rock Mechanics Site Descriptive Modelling Strategy. Similar strategies are being developed for other disciplines. The objective of the strategy is that it should guide the practical implementation of evaluating site specific data during the Site Investigations. It is also understood that further development may be needed. This methodology enables the crystalline rock mass to be characterised in terms of the quality at different sites, for considering rock engineering constructability, and for providing the input to numerical models and performance assessment calculations. The model describes the initial stresses and the distribution of deformation and strength properties of the intact rock, of fractures and fracture zones, and of the rock mass. The rock mass mechanical properties are estimated by empirical relations and by numerical simulations. The methodology is based on estimation of mechanical properties using both empirical and heroretical/numerical approaches; and estimation of in situ rock stress using judgement and numerical modelling, including the influence of fracture zones. These approaches are initially used separately, and then combined to produce the required characterisation estimates. The methodology was evaluated with a Test Case at the Aespoe Hard Rock Laboratory in Sweden. The quality control aspects are an important feature of the methodology: these include Protocols to ensure the structure and coherence of the procedures used, regular meetings to enhance communication, feedback from internal and external reviewing, plus the recording of an audit trail of the development steps and decisions made. The strategy will be reviewed and, if required, updated as appropriate.

  17. Geo-Mechanical Characterization of Carbonate Rock Masses by Means of Laser Scanner Technique

    Science.gov (United States)

    Palma, Biagio; Parise, Mario; Ruocco, Anna

    2017-12-01

    Knowledge of the geometrical and structural setting of rock masses is crucial to evaluate the stability and to design the most suitable stabilization works. In this work we use the Terrestrial Laser Scanning (TLS) at the site of the Grave of the Castellana Caves, a famous show cave in southern Italy. The Grave is the natural access to the cave system, produced by collapse of the vault, due to upward progression of instabilities in the carbonate rock masses. It is about 55-m high, bell-shaped, with maximum width of 120 m. Aim of the work is the characterization of carbonate rock masses from the structural and geo-mechanical standpoints through the use of innovative survey techniques. TLS survey provides a product consisting of millions of geo-referenced points, to be managed in space, to become a suitable database for the morphological and geological-structural analysis. Studying by means of TLS a rock face, partly inaccessible or located in very complex environments, allows to investigate slopes in their overall areal extent, thus offering advantages both as regards safety of the workers and time needed for the survey. In addition to TLS, the traditional approach was also followed by performing scanlines surveys along the rims of the Grave, following the ISRM recommendations for characterization of discontinuity in rock masses. A quantitative comparison among the data obtained by TLS technique and those deriving from the classical geo-mechanical survey is eventually presented, to discuss potentiality of drawbacks of the different techniques used for surveying the rock masses.

  18. Study of deep fracturation of granitic rock mass. Documentary study

    International Nuclear Information System (INIS)

    Bles, J.L.; Landry, J.

    1984-01-01

    This documentary study realized with the financial support of the European Communities and the CEA aims at the utilization of available data for the understanding of the evolution of natural fractures in granitic rocks from the surface to deep underground. The Mt Blanc road tunnel, the EDF's Arc-Isere gallerie, the Auriat deep borehole and the Pyrenean rock mass of Bassies are studied because detailed structural and geological studies have been realized these last 20 years. In this study are more particularly analyzed the relationship between small fractures and large faults, evolution with depth of fracture density and direction, consequences of rock decompression and relationship between fracturation and groundwater

  19. Rock History and Culture

    OpenAIRE

    Gonzalez, Éric

    2013-01-01

    Two ambitious works written by French-speaking scholars tackle rock music as a research object, from different but complementary perspectives. Both are a definite must-read for anyone interested in the contextualisation of rock music in western popular culture. In Une histoire musicale du rock (i.e. A Musical History of Rock), rock music is approached from the point of view of the people – musicians and industry – behind the music. Christophe Pirenne endeavours to examine that field from a m...

  20. Mechanical Properties and Acoustic Emission Properties of Rocks with Different Transverse Scales

    Directory of Open Access Journals (Sweden)

    Xi Yan

    2017-01-01

    Full Text Available Since the stability of engineering rock masses has important practical significance to projects like mining, tunneling, and petroleum engineering, it is necessary to study mechanical properties and stability prediction methods for rocks, cementing materials that are composed of minerals in all shapes and sizes. Rocks will generate acoustic emission during damage failure processes, which is deemed as an effective means of monitoring the stability of coal rocks. In the meantime, actual mining and roadway surrounding rocks tend to have transverse effects; namely, the transverse scale is larger than the length scale. Therefore, it is important to explore mechanical properties and acoustic emission properties of rocks under transverse size effects. Considering the transverse scale effects of rocks, this paper employs the microparticle flow software PFC2D to explore the influence of different aspect ratios on damage mechanics and acoustic emission properties of rocks. The results show that (1 the transverse scale affects uniaxial compression strength of rocks. As the aspect ratio increases, uniaxial compression strength of rocks decreases initially and later increases, showing a V-shape structure and (2 although it affects the maximum hit rate and the strain range of acoustic emission, it has little influence on the period of occurrence. As the transverse scale increases, both damage degree and damage rate of rocks decrease initially and later increase.

  1. Rock slope instabilities in Norway: First systematic hazard and risk classification of 22 unstable rock slopes

    Science.gov (United States)

    Böhme, Martina; Hermanns, Reginald L.; Oppikofer, Thierry; Penna, Ivanna

    2016-04-01

    Unstable rock slopes that can cause large failures of the rock-avalanche type have been mapped in Norway for almost two decades. Four sites have earlier been characterized as high-risk objects based on expertise of few researchers. This resulted in installing continuous monitoring systems and set-up of an early-warning system for those four sites. Other unstable rock slopes have not been ranked related to their hazard or risk. There are ca. 300 other sites known of which 70 sites were installed for periodic deformation measurements using multiple techniques (Global Navigation Satellite Systems, extensometers, measurement bolts, and others). In 2012 a systematic hazard and risk classification system for unstable rock slopes was established in Norway and the mapping approach adapted to that in 2013. Now, the first 22 sites were classified for hazard, consequences and risk using this classification system. The selection of the first group of sites to be classified was based on an assumed high hazard or risk and importance given to the sites by Norwegian media and the public. Nine of the classified 22 unstable rock slopes are large sites that deform inhomogeneously or are strongly broken up in individual blocks. This suggests that different failure scenarios are possible that need to be analyzed individually. A total of 35 failure scenarios for those nine unstable rock slopes were considered. The hazard analyses were based on 9 geological parameters defined in the classification system. The classification system will be presented based on the Gamanjunni unstable rock slope. This slope has a well developed back scarp that exposes 150 m preceding displacement. The lateral limits of the unstable slope are clearly visible in the morphology and InSAR displacement data. There have been no single structures observed that allow sliding kinematically. The lower extend of the displacing rock mass is clearly defined in InSAR data and by a zone of higher rock fall activity. Yearly

  2. Model to Assess the Quality of Magmatic Rocks for Reliable and Sustainable Constructions

    Directory of Open Access Journals (Sweden)

    Mihaela Toderaş

    2017-10-01

    Full Text Available Geomechanical assessment of rocks requires knowledge of phenomena that occur under the influence of internal and external factors at a macroscopic or microscopic scale, when rocks are submitted to different actions. To elucidate the quantitative and qualitative geomechanical behavior of rocks, knowing their geological and physical–mechanical characteristics becomes an imperative. Mineralogical, petrographical and chemical analyses provided an opportunity to identify 15 types of igneous rocks (gabbro, diabases, granites, diorites, rhyolites, andesites, and basalts, divided into plutonic and volcanic rocks. In turn, these have been grouped into acidic, neutral (intermediate and basic magmatites. A new ranking method is proposed, based on considering the rock characteristics as indicators of quantitative assessment, and the grading system, by given points, allowing the rocks framing in admissibility classes. The paper is structured into two parts, experimental and interpretation of experimental data, showing the methodology to assess the quality of igneous rocks analyzed, and the results of theoretical and experimental research carried out on the analyzed rock types. The proposed method constitutes an appropriate instrument for assessment and verification of the requirements regarding the quality of rocks used for sustainable construction.

  3. Considerations ages of rocks analyzed at the Institute of Geosciences - University of Sao Paulo - Brazil

    International Nuclear Information System (INIS)

    Medina, E.

    1990-01-01

    This work is about the radimetric studies with the proposal to determine the age of the rocks. The rocks selected were from different places of Uruguay such as Mahoma-Guaycuru, Cerros Negros y Paso Lugo - Arroyo el Minero. The data obtained allow determine their structure as well as the location of new area with this kind of rock

  4. Prevention and forecasting of rock burst hazards in coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Lin-ming Dou; Cai-ping Lu; Zong-long Mu; Ming-shi Gao [China University of Mining & Technology, Xuzhou (China). State Key Laboratory for Coal Resource and Mine Safety

    2009-09-15

    Rock bursts signify extreme behavior in coal mine strata and severely threaten the safety of the lives of miners, as well as the effectiveness and productivity of miners. In our study, an elastic-plastic-brittle model for the deformation and failure of coal/rock was established through theoretical analyses, laboratory experiments and field testing, simulation and other means, which perfectly predict sudden and delayed rock bursts. Based on electromagnetic emission (EME), acoustic emission (AE) and microseismic (MS) effects in the process from deformation until impact rupture of coal-rock combination samples, a multi-parameter identification of premonitory technology was formed, largely depending on these three forms of emission. Thus a system of classification for forecasting rock bursts in space and time was established. We have presented the intensity weakening theory for rock bursts and a strong-soft-strong (3S) structural model for controlling the impact on rock surrounding roadways, with the objective of laying a theoretical foundation and establishing references for parameters for the weakening control of rock bursts. For the purpose of prevention, key technical parameters of directional hydraulic fracturing are revealed. Based on these results, as well as those from deep-hole controlled blasting in coal seams and rock, integrated control techniques were established and anti-impact hydraulic props, suitable for roadways subject to hazards from rockbursts have also been developed. These technologies have been widely used in most coal mines in China, subject to these hazards and have achieved remarkable economic and social benefits. 28 refs., 9 figs., 1 tab.

  5. Trends in Streamflow Characteristics of Selected Sites in the Elkhorn River, Salt Creek, and Lower Platte River Basins, Eastern Nebraska, 1928-2004, and Evaluation of Streamflows in Relation to Instream-Flow Criteria, 1953-2004

    Science.gov (United States)

    Dietsch, Benjamin J.; Godberson, Julie A.; Steele, Gregory V.

    2009-01-01

    The Nebraska Department of Natural Resources approved instream-flow appropriations on the Platte River to maintain fish communities, whooping crane roost habitat, and wet meadows used by several wild bird species. In the lower Platte River region, the Nebraska Game and Parks Commission owns an appropriation filed to maintain streamflow for fish communities between the Platte River confluence with the Elkhorn River and the mouth of the Platte River. Because Elkhorn River flow is an integral part of the flow in the reach addressed by this appropriation, the Upper Elkhorn and Lower Elkhorn Natural Resources Districts are involved in overall management of anthropogenic effects on the availability of surface water for instream requirements. The Physical Habitat Simulation System (PHABSIM) and other estimation methodologies were used previously to determine instream requirements for Platte River biota, which led to the filing of five water appropriations applications with the Nebraska Department of Natural Resources in 1993 by the Nebraska Game and Parks Commission. One of these requested instream-flow appropriations of 3,700 cubic feet per second was for the reach from the Elkhorn River to the mouth of the Platte River. Four appropriations were granted with modifications in 1998, by the Nebraska Department of Natural Resources. Daily streamflow data for the periods of record were summarized for 17 streamflow-gaging stations in Nebraska to evaluate streamflow characteristics, including low-flow intervals for consecutive durations of 1, 3, 7, 14, 30, 60, and 183 days. Temporal trends in selected streamflow statistics were not adjusted for variability in precipitation. Results indicated significant positive temporal trends in annual flow for the period of record at eight streamflow-gaging stations - Platte River near Duncan (06774000), Platte River at North Bend (06796000), Elkhorn River at Neligh (06798500), Logan Creek near Uehling (06799500), Maple Creek near Nickerson

  6. Natural radioactivity of the rocks from the Moon and planets

    Energy Technology Data Exchange (ETDEWEB)

    Surkov, Yu.A. (AN SSSR, Moscow. Inst. Geokhimii i Analiticheskoj Khimii)

    1982-01-01

    Tha data on natural radioactivity of rocks (U, Th and K contents) from the Moon, Venus and Mars obtained by means of cosmic means are analyzed. The Moon rock radioactivity has been measured in situ (from orbital vehicles) as well as in the samples of lunar material delivered to the Earth and as for Venus and Mars rocks - by landing vehicles. It has been found that the main specific feature of the Moon and the Earth group planets is the presence of two geomorphological types of the structure of their surface composed by two different types of the matter. The ancient continent regions are made up by feldspar rock - gabbroanorthosite at the Moon (and possibly at the Mars) and granite-metamorphic at the Earth (and possibly at the Venus). The younger ''marine'' regions are composed by basalt rock. The presence at the Moon of two types of crust (marine and continental ones) having a different nature is clearly reflected on the Moon radioactivity map where marine regions (15% of the total surface) which have high radioactivity and continental regions with a relatively low radioactivity can be seen. The discovery of rocks on the Venus surface highly enriched by U, Th and K speaks of their melting from the primary matter in the depth of the Earth. The Marsian rock by the natural radioelement content is close to igneous rocks of the Earth crust of the basic composition and lunar marine basalts.

  7. Natural radioactivity of the rocks from the Moon and planets

    International Nuclear Information System (INIS)

    Surkov, Yu.A.

    1982-01-01

    Tha data on natural radioactivity of rocks (U, Th and K contents) from the Moon, Venus and Mars obtained by means of cosmic means are analyzed. The Moon rock radioactivity has been measured in situ (from orbital vehicles) as well as in the samples of lunar material delivered to the Earth and as for Venus and Mars rocks - by landing vehicles. It has been found that the main specific feature of the Moon and the Earth group planets is the presence of two geomorphological types of the structure of their surface composed by two different types of the matter. The ancient contineent regions are made up by feldspar rock - gabbroanorthosite at the Moon (and possibly at the Mars) and granite-metamorphic at the Earth (and possibly at the Venus). The younger ''marine'' regions are composed by basalt rock. The presence at the Moon of two types of crust (marine and continental ones) having a different nature is clearly reflected on the Moon radioactivity map where marine regions (15% of the total surface) which have high radioactivity and continental regions with a relatively low radioactivity can be seen. The discovery of rocks on the Venus surface highly enriched by U, Th and K speaks of their melting from the primary matter in the depth of the Earth. The Marsian rock by the natural radioelement content is close to igneous rocks of the Earth crust of the basic composition and lunar marine basalts

  8. Microstructural controls on the macroscopic behavior of geo-architected rock samples

    Science.gov (United States)

    Mitchell, C. A.; Pyrak-Nolte, L. J.

    2017-12-01

    Reservoir caprocks, are known to span a range of mechanical behavior from elastic granitic units to visco-elastic shale units. Whether a rock will behave elastically, visco-elastically or plastically depends on both the compositional and textural or microsctructural components of the rock, and how these components are spatially distributed. In this study, geo-architected caprock fabrication was performed to develop synthetic rock to study the role of rock rheology on fracture deformations, fluid flow and geochemical alterations. Samples were geo-architected with Portland Type II cement, Ottawa sand, and different clays (kaolinite, illite, and Montmorillonite). The relative percentages of these mineral components are manipulated to generate different rock types. With set protocols, the mineralogical content, texture, and certain structural aspects of the rock were controlled. These protocols ensure that identical samples with the same morphological and mechanical characteristics are constructed, thus overcoming issues that may arise in the presence of heterogeneity and high anisotropy from natural rock samples. Several types of homogeneous geo-architected rock samples were created, and in some cases the methods were varied to manipulate the physical parameters of the rocks. Characterization of rocks that the samples exhibit good repeatability. Rocks with the same mineralogical content generally yielded similar compressional and shear wave velocities, UCS and densities. Geo-architected rocks with 10% clay in the matrix had lower moisture content and effective porosities than rocks with no clay. The process by which clay is added to the matrix can strongly affect the resulting compressive strength and physical properties of the geo-architected sample. Acknowledgment: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Geosciences Research Program under Award Number (DE-FG02-09ER16022).

  9. Investigation of impact phenomena on the marine structures: Part I - On the behaviour of thin-walled double bottom tanker during rock-structure interaction

    Science.gov (United States)

    Prabowo, A. R.; Cho, H. J.; Byeon, J. H.; Bae, D. M.; Sohn, J. M.

    2018-01-01

    Predicted loads, such as crew, cargo, and structure have been applied as main inputs during ship design and analysis. However, unexpected events on the sea has high possibility to deliver remarkable losses for ship, industry, and environment. Previous oil spill incident by the Exxon Valdez in Alaska is the perfect example which an environmental damage and industry loss are initiated by an impact phenomenon on the ship, i.e. grounding. Even though hull arrangement has adopted double hull system, grounding may threaten ship safety in various scenarios. This situation pushes society to demand sustainable investigation for impact phenomena on water transportation mode to update understanding in the phenomenon and ensure structural safety during ship operation. This work aimed to study structural behaviour of chemical tanker as a marine structure under impact, namely ship grounding. Bottom raking case was considered to be calculated by virtual experiment. The study was performed using nonlinear finite element (FE) method and an idealised geometry of seabed rock would be deployed to be hard obstruction. Observation on the selected crashworthiness criteria, i.e. internal energy and crushing force indicated that as advanced penetration occurred on the ship structure, the absorbed strain energy continued to increase, while major fluctuation appeared during the initial contact between obstruction and ship happened. Damage extent of several structural members during the crushing process was shown, which concluded that the bottom plating had the largest severity in forms of tearing mode among of all members on the bottom structure.

  10. Rapid formation of rock armour for soil - rock fragment mixture during simulated rainfall

    Science.gov (United States)

    Poultney, E.; McGrath, G. S.; Hinz, C.

    2009-04-01

    Preventing erosion is an important issue in disturbed semi-arid and arid landscapes. This is in particular of highest importance for mining companies while undertaking land rehabilitation. An onsite investigation of the impact of surface rock fragments on erosion was conducted at Telfer goldmine in the Great Sandy Desert, Western Australia. The study site is a waste rock dump designed to mimic the concave slope of a natural mesa to both discourage erosion and blend in with its natural surroundings. Four treatments were used to construct the slope: two are topsoil mixed with rock fragments, and two are unmixed topsoil. A field study investigating erosion rills, particle size distribution, rock fragment coverage surface roughness and vegetation was carried out to determine changes down and across slope. The treatments constructed by mixing topsoil and rock fragments are more stable and show rock fragment distributions that more closely resemble patterns found on natural mesas surrounding Telfer. A controlled study using trays of topsoil mixed with rock fragment volumes of 50%, 60%, 70% and 80% were used to investigate how varying mixtures of rock fragments and topsoil erode using rainfall intensities between 20 and 100 mm h-1. Two runs of 25 minutes each were used to assess the temporal evolution of rock armouring. Surface coverage results converged for the 50%, 60% and 70% mixtures after the first run to coverage of about 90%, suggesting that fine sediment proportion does not affect rate and degree of rock armouring.

  11. Electric polarization switching in an atomically thin binary rock salt structure

    Science.gov (United States)

    Martinez-Castro, Jose; Piantek, Marten; Schubert, Sonja; Persson, Mats; Serrate, David; Hirjibehedin, Cyrus F.

    2018-01-01

    Inducing and controlling electric dipoles is hindered in the ultrathin limit by the finite screening length of surface charges at metal-insulator junctions1-3, although this effect can be circumvented by specially designed interfaces4. Heterostructures of insulating materials hold great promise, as confirmed by perovskite oxide superlattices with compositional substitution to artificially break the structural inversion symmetry5-8. Bringing this concept to the ultrathin limit would substantially broaden the range of materials and functionalities that could be exploited in novel nanoscale device designs. Here, we report that non-zero electric polarization can be induced and reversed in a hysteretic manner in bilayers made of ultrathin insulators whose electric polarization cannot be switched individually. In particular, we explore the interface between ionic rock salt alkali halides such as NaCl or KBr and polar insulating Cu2N terminating bulk copper. The strong compositional asymmetry between the polar Cu2N and the vacuum gap breaks inversion symmetry in the alkali halide layer, inducing out-of-plane dipoles that are stabilized in one orientation (self-poling). The dipole orientation can be reversed by a critical electric field, producing sharp switching of the tunnel current passing through the junction.

  12. Safety management system during rock blasting at FRFCF construction site

    International Nuclear Information System (INIS)

    Vijayakumaran, C.; Kandasamy, S.; Satpathy, K.K.

    2016-01-01

    Blasting is an important activity during rock excavation to reach required depth for obtaining stability of the civil structure. For the construction of various Plant Buildings of Fast Reactor Fuel Cycle Facility (FRFCF), IGCAR at Kalpakkam, based on the geological survey it is required to reach a depth of 21.4 meters from existing ground level. This paper details about the procedures and precaution adopted during the rock blasting activities at FRFCF site. The volume of rock removed by blasting was 3 lakh cubic meters. The total number of blasting carried out was 304 using 105.73 tons of blasting material. The entire blasting work could be completed within 174 days without any incident. (author)

  13. Proceedings of a technical session on rock mechanics ''Advance in laboratory sample testing''

    International Nuclear Information System (INIS)

    Come, B.

    1984-01-01

    This report brings together a series of papers about rock mechanics. The meeting was divided into three sessions, which dealt with the three main types of rock formation currently considered in the CEC Programme: granite, clay and salt. Safe disposal of high-level radioactive waste involves the proper design of deep underground repositories. This necessitates an in-depth knowledge of the mechanical properties of the rock mass. The behaviour of the rock mass must be known both for the construction and the operation (heating effects) of the repository. Usually, the dominant factor for designing an underground structure is the fracturing of the rock mass. In the present case, the rock is chosen with a very low fracturing. Therefore, the mechanical properties of the formation are mainly those of the rock matrix. These properties are obtained, at least in a first exploratory step, by laboratory testing of rock samples obtained by core-drilling from surface. This aspect of rock characterization was thought to deserve a special technical meeting, in order to bring together most of the results obtained in this field by contracting partners of the CEC for the years 1980-82

  14. Experimental and Numerical Investigation of Rock Dynamic Fracture

    Directory of Open Access Journals (Sweden)

    Aliasghar Mirmohammadlou

    2017-06-01

    Full Text Available Rapid development of engineering activities expands through a variety of rock engineering processes such as drilling, blasting, mining and mineral processing. These activities require rock dynamic fracture mechanics method to characterize the rock behavior. Dynamic fracture toughness is an important parameter for the analysis of engineering structures under dynamic loading. Several experimental methods are used for determination of dynamic fracture properties of materials. Among them, the Hopkinson pressure bar and the drop weight have been frequently used for rocks. On the other hand, numerical simulations are very useful in dynamic fracture studies. Among vast variety of numerical techniques, the powerful extended finite element method (XFEM enriches the finite element approximation with appropriate functions extracted from the fracture mechanics solution around a crack-tip. The main advantage of XFEM is its capability in modeling different on a fixed mesh, which can be generated without considering the existence of discontinuities. In this paper, first, the design of a drop weight test setup is presented. Afterwards, the experimental tests on igneous (basalt and calcareous (limestone rocks with single-edge-cracked bend specimen are discussed. Then, each experimental test is modeled with the XFEM code. Finally, the obtained experimental and numerical results are compared. The results indicate that the experimentally predicted dynamic fracture toughness has less than 8 percent difference with calculated dynamic fracture toughness from extended finite element method

  15. Semantic modeling of plastic deformation of polycrystalline rock

    Science.gov (United States)

    Babaie, Hassan A.; Davarpanah, Armita

    2018-02-01

    We have developed the first iteration of the Plastic Rock Deformation (PRD) ontology by modeling the semantics of a selected set of deformational processes and mechanisms that produce, reconfigure, displace, and/or consume the material components of inhomogeneous polycrystalline rocks. The PRD knowledge model also classifies and formalizes the properties (relations) that hold between instances of the dynamic physical and chemical processes and the rock components, the complex physio-chemical, mathematical, and informational concepts of the plastic rock deformation system, the measured or calculated laboratory testing conditions, experimental procedures and protocols, the state and system variables, and the empirical flow laws that define the inter-relationships among the variables. The ontology reuses classes and properties from several existing ontologies that are built for physics, chemistry, biology, and mathematics. With its flexible design, the PRD ontology is well positioned to incrementally develop into a model that more fully represents the knowledge of plastic deformation of polycrystalline rocks in the future. The domain ontology will be used to consistently annotate varied data and information related to the microstructures and the physical and chemical processes that produce them at different spatial and temporal scales in the laboratory and in the solid Earth. The PRDKB knowledge base, when built based on the ontology, will help the community of experimental structural geologists and metamorphic petrologists to coherently and uniformly distribute, discover, access, share, and use their data through automated reasoning and integration and query of heterogeneous experimental deformation data that originate from autonomous rock testing laboratories.

  16. Comparison of Crack Initiation, Propagation and Coalescence Behavior of Concrete and Rock Materials

    Science.gov (United States)

    Zengin, Enes; Abiddin Erguler, Zeynal

    2017-04-01

    There are many previously studies carried out to identify crack initiation, propagation and coalescence behavior of different type of rocks. Most of these studies aimed to understand and predict the probable instabilities on different engineering structures such as mining galleries or tunnels. For this purpose, in these studies relatively smaller natural rock and synthetic rock-like models were prepared and then the required laboratory tests were performed to obtain their strength parameters. By using results provided from these models, researchers predicted the rock mass behavior under different conditions. However, in the most of these studies, rock materials and models were considered as contains none or very few discontinuities and structural flaws. It is well known that rock masses naturally are extremely complex with respect to their discontinuities conditions and thus it is sometimes very difficult to understand and model their physical and mechanical behavior. In addition, some vuggy rock materials such as basalts and limestones also contain voids and gaps having various geometric properties. Providing that the failure behavior of these type of rocks controlled by the crack initiation, propagation and coalescence formed from their natural voids and gaps, the effect of these voids and gaps over failure behavior of rocks should be investigated. Intact rocks are generally preferred due to relatively easy side of their homogeneous characteristics in numerical modelling phases. However, it is very hard to extract intact samples from vuggy rocks because of their complex pore sizes and distributions. In this study, the feasibility of concrete samples to model and mimic the failure behavior vuggy rocks was investigated. For this purpose, concrete samples were prepared at a mixture of %65 cement dust and %35 water and their physical and mechanical properties were determined by laboratory experiments. The obtained physical and mechanical properties were used to

  17. Teaching the Rock Cycle with Ease.

    Science.gov (United States)

    Bereki, Debra

    2000-01-01

    Describes a hands-on lesson for teaching high school students the concept of the rock cycle using sedimentary, metamorphic, and igneous rocks. Students use a rock cycle diagram to identify pairs of rocks. From the rock cycle, students explain on paper how their first rock became the second rock and vice versa. (PVD)

  18. Tales from the tomb: the microbial ecology of exposed rock surfaces.

    Science.gov (United States)

    Brewer, Tess E; Fierer, Noah

    2018-03-01

    Although a broad diversity of eukaryotic and bacterial taxa reside on rock surfaces where they can influence the weathering of rocks and minerals, these communities and their contributions to mineral weathering remain poorly resolved. To build a more comprehensive understanding of the diversity, ecology and potential functional attributes of microbial communities living on rock, we sampled 149 tombstones across three continents and analysed their bacterial and eukaryotic communities via marker gene and shotgun metagenomic sequencing. We found that geographic location and climate were important factors structuring the composition of these communities. Moreover, the tombstone-associated microbial communities varied as a function of rock type, with granite and limestone tombstones from the same cemeteries harbouring taxonomically distinct microbial communities. The granite and limestone-associated communities also had distinct functional attributes, with granite-associated bacteria having more genes linked to acid tolerance and chemotaxis, while bacteria on limestone were more likely to be lichen associated and have genes involved in photosynthesis and radiation resistance. Together these results indicate that rock-dwelling microbes exhibit adaptations to survive the stresses of the rock surface, differ based on location, climate and rock type, and seem pre-disposed to different ecological strategies (symbiotic versus free-living lifestyles) depending on the rock type. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  19. Recreating Rocks

    DEFF Research Database (Denmark)

    Posth, Nicole R

    2008-01-01

    Nicole Posth and colleagues spent a month touring South African rock formations in their quest to understand the origin of ancient iron and silicate layers.......Nicole Posth and colleagues spent a month touring South African rock formations in their quest to understand the origin of ancient iron and silicate layers....

  20. Hydrological characteristics of Japanese rock

    International Nuclear Information System (INIS)

    Ijiri, Yuji; Sawada, Atsushi; Akahori, Kuniaki

    1999-11-01

    It is crucial to evaluate the hydrogeological characteristics of rock in Japan in order to assess the performance of geosphere. This report summarizes the hydrogeological characteristics of various rock types obtained from broad literature surveys and the fields experiments at the Kamaishi mine in northern Japan and at the Tono mine in central Japan. It is found that the hydraulic conductivity of rock mass ranges from 10 -9 m/s to 10 -8 m/s, whereas the hydraulic conductivity of fault zone ranges from 10 -9 m/s to 10 -3 m/s. It is also found that the hydraulic conductivity tends to decrease with depth. Therefore, the hydraulic conductivity of rock mass at the depth of a repository will be smaller than above values. From the investigations at outcrops and galleries throughout the country, fractures are observed as potential pathways in all rock types. All kinds of crystalline rocks and pre-Neogene sedimentary rocks are classified as fractured media where fracture flow is dominant. Among these rocks, granitic rock is considered the archetype fractured media. On the other hand, andesite, tuff and Neogene sedimentary rocks are considered as intermediate between fractured media and porous media where flow in fractures as well as in rock matrix are significant. (author)

  1. Frictional sliding in layered rock: laboratory-scale experiments

    International Nuclear Information System (INIS)

    Buescher, B.J.; Perry, K.E. Jr.; Epstein, J.S.

    1996-09-01

    The work is part of the rock mechanics effort for the Yucca Mountain Site Characterization Program. The laboratory-scale experiments are intended to provide high quality data on the mechanical behavior of jointed structures that can be used to validate complex numerical models for rock-mass behavior. Frictional sliding between simulated rock joints was studied using phase shifting moire interferometry. A model, constructed from stacks of machined and sandblasted granite plates, contained a central hole bore normal to the place so that frictional slip would be induced between the plates near the hole under compressive loading. Results show a clear evolution of slip with increasing load. Since the rock was not cycled through loading- unloading, the quantitative differences between the three data sets are probably due to a ''wearing-in'' effect. The highly variable spatial frequency of the data is probably due to the large grain size of the granite and the stochastic frictional processes. An unusual feature of the evolution of slip with increasing load is that as the load gets larger, some plates seem to return to a null position. Figs, 6 refs

  2. Ship Grounding on Rock - I. Theory

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup

    1997-01-01

    and transverse frames, floors and bulkheads. The expressions are derived by use of an energy method or a type of 'upper bound' method which rigorously takes into account the effects of large plastic deformations, friction and fracture. A high level of generality for the methodology has been obtained...... by postulating a global mode of deformation for the structure around the rock with one free parameter, the plate split angle, related to the shape of thedeformation mode. It is assumed that intersections between structural components stay intact during the entire deformation process so the resistance...

  3. Rock Goes to School on Screen: A Model for Teaching Non-"Learned" Musics Derived from the Films "School of Rock" (2003) and "Rock School" (2005)

    Science.gov (United States)

    Webb, Michael

    2007-01-01

    What can be learned from two films with "rock" and "school" in their titles, about rock in school and about music and schooling more broadly? "School of Rock" (2003), a "family comedy," and "Rock School" (2005), a documentary, provoke a range of questions, ideological and otherwise, surrounding the inclusion of rock in formal instructional…

  4. Effect of Interaction and Rocking Motion on The Earthquake Response of Buildings

    Directory of Open Access Journals (Sweden)

    Gholamreza Havaei

    2015-03-01

    Full Text Available Usually structures are designed under codes based on the assumption that the soil stiffness is infinite, so the foundation rests firmly on the soil. In many cases, the overturning moment due to the lateral forces may exceed the resisting moment due to the gravity forces. Thus, this may cause a foundation uplift because in reality the soil stiffness is not infinite and the structure stands up under gravity forces. The phenomenon of foundation uplifting and its impact on the soil are known as the rocking motion.This study investigates the influence of the rocking motion and interaction by the yielding base plates on the nonlinear behavior of steel structures under dynamic analysis. More specifically, Three- five and seven -storied structuresare designed with ordinary ductility, then the structuresare analyzed in rigid and deformable base plate cases with using the ABAQUS software.The results show that the rocking motion and Interaction decrease the response of buildings such as the base shear, the axial force of columns and the strain energy but also increase the natural period.

  5. Spinel–rock salt transformation in LiCoMnO4−δ

    Science.gov (United States)

    Reeves-McLaren, Nik; Sharp, Joanne; Beltrán-Mir, Héctor; Rainforth, W. Mark; West, Anthony R.

    2016-01-01

    The transformation on heating LiCoMnO4, with a spinel structure, to LiCoMnO3, with a cation-disordered rock salt structure, accompanied by loss of 25% of the oxygen, has been followed using a combination of diffraction, microscopy and spectroscopy techniques. The transformation does not proceed by a topotactic mechanism, even though the spinel and rock salt phases have a similar, cubic close-packed oxygen sublattice. Instead, the transformation passes through two stages involving, first, precipitation of Li2MnO3, leaving behind a Li-deficient, Co-rich non-stoichiometric spinel and, second, rehomogenization of the two-phase assemblage, accompanied by additional oxygen loss, to give the homogeneous rock salt final product; a combination of electron energy loss spectroscopy and X-ray absorption near edge structure analyses showed oxidation states of Co2+ and Mn3+ in LiCoMnO3. Subsolidus phase diagram determination of the Li2O-CoOx-MnOy system has established the compositional extent of spinel solid solutions at approximately 500°C. PMID:26997883

  6. Deformation mechanisms and melt nano-structures in experimentally deformed olivine-orthopyroxene rocks with low melt fractions

    NARCIS (Netherlands)

    Kloe, P.A. de

    2001-01-01

    The major part of the Earth’s upper mantle is thought to be solid, with some regions in the mantle where the rocks contain a small melt fraction These partially molten rocks are associated with important geological processes such as magma production beneath mid-oceanic ridges and may also play an

  7. Grinding into Soft, Powdery Rock

    Science.gov (United States)

    2004-01-01

    This hole in a rock dubbed 'Clovis' is the deepest hole drilled so far in any rock on Mars. NASA's Mars Exploration Rover Spirit captured this view with its microscopic imager on martian sol 217 (Aug. 12, 2004) after drilling 8.9 millimeters (0.35 inch) into the rock with its rock abrasion tool. The view is a mosaic of four frames taken by the microscopic imager. The hole is 4.5 centimeters (1.8 inches) in diameter. Clovis is key to a developing story about environmental change on Mars, not only because it is among the softest rocks encountered so far in Gusev Crater, but also because it contains mineral alterations that extend relatively deep beneath its surface. In fact, as evidenced by its fairly crumbly texture, it is possibly the most highly altered volcanic rock ever studied on Mars. Scientific analysis shows that the rock contains higher levels of the elements sulfur, chlorine, and bromine than are normally encountered in basaltic rocks, such as a rock dubbed 'Humphrey' that Spirit encountered two months after arriving on Mars. Humphrey showed elevated levels of sulfur, chlorine, and bromine only in the outermost 2 millimeters (less than 0.1 inch) of its surface. Clovis shows elevated levels of the same elements along with the associated softness of the rock within a borehole that is 4 times as deep. Scientists hope to compare Clovis to other, less-altered rocks in the vicinity to assess what sort of water-based processes altered the rock. Hypotheses include transport of sulfur, chlorine, and bromine in water vapor in volcanic gases; hydrothermal circulation (flow of volcanically heated water through rock); or saturation in a briny soup containing the same elements. In this image, very fine-grained material from the rock has clumped together by electrostatic attraction and fallen into the borehole. NASA/JPL/Cornell/USGS

  8. SAPHYR: the Swiss Atlas of PHYsical properties of Rocks

    Science.gov (United States)

    Wenning, Q. C.; Zappone, A. S.; Kissling, E.

    2015-12-01

    The Swiss Atlas of PHYsical properties of Rocks (SAPHYR) is a multi-year project, aiming to compile a comprehensive data set on physical properties of rocks exposed in Switzerland and surrounding areas. The ultimate goal of SAPHYR is to make these data accessible to an open and wide public, such as industrial, engineering, land and resource planning companies, as well as academic institutions. Since the early sixties worldwide geophysicists, petrologists, and engineers, focused their work on laboratory measurements of rocks physical properties, and their relations with microstructures, mineralogical compositions and other rock parameters, in the effort to constrain the geological interpretation of geophysical surveys. In combination with efforts to investigate deep structure of the continental crust by controlled source seismology, laboratories capable to reproduce pressure and temperature conditions to depth of 50km and more collected measurements of various parameters on a wide variety of rock types. In recent years, the increasing interest on non-traditional energy supply, (deep geothermal energy, shale gas) and CO2 storage renovated the interests in physical characterization of the deep underground. The idea to organize those laboratory data into a geographically referenced database (GIS) is supported by the Swiss Commission for Geophysics. The data refer to density and porosity, seismic, magnetic, thermal properties, permeability and electrical properties. An effort has been placed on collecting samples and measuring the physical properties of lithologies that are poorly documented in literature. The phase of laboratory measurements is still in progress. At present SAPHYR focuses towards developing a 3-D physical properties model of the Swiss subsurface, using the structure of the exposed geology, boreholes data and seismic surveys, combined with lab determined pressure and temperature derivatives. An early version of the final product is presented here.

  9. THM-coupled modeling of selected processes in argillaceous rock relevant to rock mechanics

    International Nuclear Information System (INIS)

    Czaikowski, Oliver

    2012-01-01

    Scientific investigations in European countries other than Germany concentrate not only on granite formations (Switzerland, Sweden) but also on argillaceous rock formations (France, Switzerland, Belgium) to assess their suitability as host and barrier rock for the final storage of radioactive waste. In Germany, rock salt has been under thorough study as a host rock over the past few decades. According to a study by the German Federal Institute for Geosciences and Natural Resources, however, not only salt deposits but also argillaceous rock deposits are available at relevant depths and of extensions in space which make final storage of high-level radioactive waste basically possible in Germany. Equally qualified findings about the suitability/unsuitability of non-saline rock formations require fundamental studies to be conducted nationally because of the comparatively low level of knowledge. The article presents basic analyses of coupled mechanical and hydraulic properties of argillaceous rock formations as host rock for a repository. The interaction of various processes is explained on the basis of knowledge derived from laboratory studies, and open problems are deduced. For modeling coupled processes, a simplified analytical computation method is proposed and compared with the results of numerical simulations, and the limits to its application are outlined. (orig.)

  10. Aespoe Hard Rock Laboratory. The TASS-tunnel. Geological mapping

    Energy Technology Data Exchange (ETDEWEB)

    Hardenby, Carljohan (Vattenfall Power Consultant AB (Sweden)); Sigurdsson, Oskar (HAskGeokonsult AB (Sweden))

    2010-12-15

    The project entitled 'Sealing of tunnel at great depth' (Fintaetning av tunnel paa stort djup) needed a new tunnel in an area as undisturbed as possible and with cross-cutting water-bearing structures. The new tunnel, which was given the name TASS, was excavated on the -450 m level of SKB's Aespoe Hard Rock Laboratory (Aespoe HRL). The length of the tunnel is approximately 80 m and the theoretical tunnel area 19 m2. As is the case with all the other tunnels of the Aespoe HRL, the new tunnel has been geologically mapped. In addition, laser scanning combined with digital photography has been carried out. The tunnel was also used to test various types of explosives, borehole layouts and drilling techniques. The geological mapping of tunnel floor, walls and roof took place on four major occasions when a halt was made in tunnel excavation to allow for various tests. Before the mapping started on these occasions, laser scanning took place. The tunnel faces were mapped after each round (drilling, blasting and unloading). The present report describes the geological features of the tunnel and briefly how the laser scanning was performed. Water-bearing structures have been compared to similar structures in the neighbouring tunnels. The rock type names used here follow the old established Aespoe HRL nomenclature. Narrow (<0.1 m wide) dykes are normally mapped as fracture fillings. The dominating rock type is Aespoe diorite, which constitutes some 90 % of the rock mass. It is mostly mapped as fresh rock. . Minor constituents of the rock mass are fine-grained granite, hybrid rock, pegmatite, quartz veins/lenses and undifferentiated mafic rock. The mapping of fractures and deformation zones considers a number of parameters such as number of fractures, open/healed, width, length, description of fracture surfaces (roughness, planarity, etc), fracture filling, alteration and water. The deformation zones are discriminated into two main categories (&apos

  11. Aespoe Hard Rock Laboratory. The TASS-tunnel. Geological mapping

    International Nuclear Information System (INIS)

    Hardenby, Carljohan; Sigurdsson, Oskar

    2010-12-01

    The project entitled 'Sealing of tunnel at great depth' (Fintaetning av tunnel paa stort djup) needed a new tunnel in an area as undisturbed as possible and with cross-cutting water-bearing structures. The new tunnel, which was given the name TASS, was excavated on the -450 m level of SKB's Aespoe Hard Rock Laboratory (Aespoe HRL). The length of the tunnel is approximately 80 m and the theoretical tunnel area 19 m 2 . As is the case with all the other tunnels of the Aespoe HRL, the new tunnel has been geologically mapped. In addition, laser scanning combined with digital photography has been carried out. The tunnel was also used to test various types of explosives, borehole layouts and drilling techniques. The geological mapping of tunnel floor, walls and roof took place on four major occasions when a halt was made in tunnel excavation to allow for various tests. Before the mapping started on these occasions, laser scanning took place. The tunnel faces were mapped after each round (drilling, blasting and unloading). The present report describes the geological features of the tunnel and briefly how the laser scanning was performed. Water-bearing structures have been compared to similar structures in the neighbouring tunnels. The rock type names used here follow the old established Aespoe HRL nomenclature. Narrow (<0.1 m wide) dykes are normally mapped as fracture fillings. The dominating rock type is Aespoe diorite, which constitutes some 90 % of the rock mass. It is mostly mapped as fresh rock. . Minor constituents of the rock mass are fine-grained granite, hybrid rock, pegmatite, quartz veins/lenses and undifferentiated mafic rock. The mapping of fractures and deformation zones considers a number of parameters such as number of fractures, open/healed, width, length, description of fracture surfaces (roughness, planarity, etc), fracture filling, alteration and water. The deformation zones are discriminated into two main categories ('increased fracturing' and

  12. Seismic response of rock joints and jointed rock mass

    International Nuclear Information System (INIS)

    Ghosh, A.; Hsiung, S.M.; Chowdhury, A.H.

    1996-06-01

    Long-term stability of emplacement drifts and potential near-field fluid flow resulting from coupled effects are among the concerns for safe disposal of high-level nuclear waste (HLW). A number of factors can induce drift instability or change the near-field flow patterns. Repetitive seismic loads from earthquakes and thermal loads generated by the decay of emplaced waste are two significant factors. One of two key technical uncertainties (KTU) that can potentially pose a high risk of noncompliance with the performance objectives of 10 CFR Part 60 is the prediction of thermal-mechanical (including repetitive seismic load) effects on stability of emplacement drifts and the engineered barrier system. The second KTU of concern is the prediction of thermal-mechanical-hydrological (including repetitive seismic load) effects on the host rock surrounding the engineered barrier system. The Rock Mechanics research project being conducted at the Center for Nuclear Waste Regulatory Analyses (CNWRA) is intended to address certain specific technical issues associated with these two KTUs. This research project has two major components: (i) seismic response of rock joints and a jointed rock mass and (ii) coupled thermal-mechanical-hydrological (TMH) response of a jointed rock mass surrounding the engineered barrier system (EBS). This final report summarizes the research activities concerned with the repetitive seismic load aspect of both these KTUs

  13. Swiss Atlas of PHYsical properties of Rocks (SAPHYR)

    Science.gov (United States)

    Zappone, Alba; Kissling, Eduard

    2015-04-01

    The Swiss Atlas of PHYsical properties of Rocks (SAPHYR), is a multi-year project, funded entirely by Swiss Commission for Geophysics (SGPK), with the aim to compile a comprehensive data set in digital form on physical properties of rocks exposed in Switzerland and surrounding regions. The ultimate goal of SAPHYR is to make these data accessible to an open and wide public including industrial, engineering, land and resource planning companies, as well as academic institutions, or simply people interested in geology. Since the early sixties worldwide many scientists, i.e. geophysicists, petrologists, and engineers, focused their work on laboratory measurements of rocks physical properties, and their relations with microstructures, mineralogical compositions and other rock parameters, in the effort to constrain the geological interpretation of geophysical surveys. Particularly in the years in which seismic reflection and refraction crustal scale projects were investigating the deep structures of the Alps, laboratories capable to reproduce the pressure and temperature ranges of the continental crust were collecting measurements of various rock parameters on a wide variety of lithologies, developing in the meantime more and more sophisticated experimental methodologies. In recent years, the increasing interest of European Countries on non-traditional energy supply, (i.e. Deep Geothermal Energy and shale gas) and CO2 storage renovated the interests in physical characterization of the deep underground. SAPHYR aims to organize all those laboratory data into a geographically referenced database (GIS). The data refer to density, porosity, permeability, and seismic, magnetic, thermal and electric properties. In the past years, effort has been placed on collecting samples and measuring the physical properties of lithologies that were poorly documented in literature. The phase of laboratory measurements is still in progress. Recently, SAPHYR project focused towards developing

  14. Introduction to numerical modeling of thermohydrologic flow in fractured rock masses

    International Nuclear Information System (INIS)

    Wang, J.S.Y.

    1980-01-01

    More attention is being given to the possibility of nuclear waste isolation in hard rock formations. The waste will generate heat which raises the temperature of the surrounding fractured rock masses and induces buoyancy flow and pressure change in the fluid. These effects introduce the potential hazard of radionuclides being carried to the biosphere, and affect the structure of a repository by stress changes in the rock formation. The thermohydrological and thermomechanical responses are determined by the fractures as well as the intact rock blocks. The capability of modeling fractured rock masses is essential to site characterization and repository evaluation. The fractures can be modeled either as a discrete system, taking into account the detailed fracture distributions, or as a continuum representing the spatial average of the fractures. A numerical model is characterized by the governing equations, the numerical methods, the computer codes, the validations, and the applications. These elements of the thermohydrological models are discussed. Along with the general review, some of the considerations in modeling fractures are also discussed. Some remarks on the research needs in modeling fractured rock mass conclude the paper

  15. Rho-associated kinase (ROCK) function is essential for cell cycle progression, senescence and tumorigenesis

    OpenAIRE

    K?mper, Sandra; Mardakheh, Faraz K; McCarthy, Afshan; Yeo, Maggie; Stamp, Gordon W; Paul, Angela; Worboys, Jonathan; Sadok, Amine; J?rgensen, Claus; Guichard, Sabrina; Marshall, Christopher J

    2016-01-01

    eLife digest Animal cells contain a structure called the cytoskeleton, which helps give the cells their shape. This structure can rapidly disassemble and reassemble, which enables cells to change their shape, move and divide into two. Many proteins are involved in controlling these processes. In particular, two proteins called ROCK1 and ROCK2 are known to be important for helping cancer cells move. However, investigations into the exact roles of these proteins have so far produced contradicto...

  16. Effects of confinement on rock mass modulus: A synthetic rock mass modelling (SRM study

    Directory of Open Access Journals (Sweden)

    I. Vazaios

    2018-06-01

    Full Text Available The main objective of this paper is to examine the influence of the applied confining stress on the rock mass modulus of moderately jointed rocks (well interlocked undisturbed rock mass with blocks formed by three or less intersecting joints. A synthetic rock mass modelling (SRM approach is employed to determine the mechanical properties of the rock mass. In this approach, the intact body of rock is represented by the discrete element method (DEM-Voronoi grains with the ability of simulating the initiation and propagation of microcracks within the intact part of the model. The geometry of the pre-existing joints is generated by employing discrete fracture network (DFN modelling based on field joint data collected from the Brockville Tunnel using LiDAR scanning. The geometrical characteristics of the simulated joints at a representative sample size are first validated against the field data, and then used to measure the rock quality designation (RQD, joint spacing, areal fracture intensity (P21, and block volumes. These geometrical quantities are used to quantitatively determine a representative range of the geological strength index (GSI. The results show that estimating the GSI using the RQD tends to make a closer estimate of the degree of blockiness that leads to GSI values corresponding to those obtained from direct visual observations of the rock mass conditions in the field. The use of joint spacing and block volume in order to quantify the GSI value range for the studied rock mass suggests a lower range compared to that evaluated in situ. Based on numerical modelling results and laboratory data of rock testing reported in the literature, a semi-empirical equation is proposed that relates the rock mass modulus to confinement as a function of the areal fracture intensity and joint stiffness. Keywords: Synthetic rock mass modelling (SRM, Discrete fracture network (DFN, Rock mass modulus, Geological strength index (GSI, Confinement

  17. Rock Physical Interpretation of the Relationship between Dynamic and Static Young's Moduli of Sedimentary Rocks

    Science.gov (United States)

    Takahashi, T.

    2017-12-01

    The static Young's modulus (deformability) of a rock is indispensable for designing and constructing tunnels, dams and underground caverns in civil engineering. Static Young's modulus which is an elastic modulus at large strain level is usually obtained with the laboratory tests of rock cores sampled in boreholes drilled in a rock mass. A deformability model of the entire rock mass is then built by extrapolating the measurements based on a rock mass classification obtained in geological site characterization. However, model-building using data obtained from a limited number of boreholes in the rock mass, especially a complex rock mass, may cause problems in the accuracy and reliability of the model. On the other hand, dynamic Young's modulus which is the modulus at small strain level can be obtained from seismic velocity. If dynamic Young's modulus can be rationally converted to static one, a seismic velocity model by the seismic method can be effectively used to build a deformability model of the rock mass. In this study, we have, therefore, developed a rock physics model (Mavko et al., 2009) to estimate static Young's modulus from dynamic one for sedimentary rocks. The rock physics model has been generally applied to seismic properties at small strain level. In the proposed model, however, the sandy shale model, one of rock physics models, is extended for modeling the static Young's modulus at large strain level by incorporating the mixture of frictional and frictionless grain contacts into the Hertz-Mindlin model. The proposed model is verified through its application to the dynamic Young's moduli derived from well log velocities and static Young's moduli measured in the tri-axial compression tests of rock cores sampled in the same borehole as the logs were acquired. This application proves that the proposed rock physics model can be possibly used to estimate static Young's modulus (deformability) which is required in many types of civil engineering applications

  18. Characterization of Unstable Rock Slopes Through Passive Seismic Measurements

    Science.gov (United States)

    Kleinbrod, U.; Burjanek, J.; Fäh, D.

    2014-12-01

    Catastrophic rock slope failures have high social impact, causing significant damage to infrastructure and many casualties throughout the world each year. Both detection and characterization of rock instabilities are therefore of key importance. An analysis of ambient vibrations of unstable rock slopes might be a new alternative to the already existing methods, e.g. geotechnical displacement measurements. Systematic measurements have been performed recently in Switzerland to study the seismic response of potential rockslides concerning a broad class of slope failure mechanisms and material conditions. Small aperture seismic arrays were deployed at sites of interest for a short period of time (several hours) in order to record ambient vibrations. Each measurement setup included a reference station, which was installed on a stable part close to the instability. Recorded ground motion is highly directional in the unstable parts of the rock slope, and significantly amplified with respect to stable areas. These effects are strongest at certain frequencies, which were identified as eigenfrequencies of the unstable rock mass. In most cases the directions of maximum amplification are perpendicular to open cracks and in good agreement with the deformation directions obtained by geodetic measurements. Such unique signatures might improve our understanding of slope structure and stability. Thus we link observed vibration characteristics with available results of detailed geological characterization. This is supported by numerical modeling of seismic wave propagation in fractured media with complex topography.For example, a potential relation between eigenfrequencies and unstable rock mass volume is investigated.

  19. Clay club catalogue of characteristics of argillaceous rocks

    International Nuclear Information System (INIS)

    2005-01-01

    The OECD/NEA Working Group on the Characterisation, the Understanding and the Performance of Argillaceous Rocks as Repository Host Formations, namely the Clay Club, examines the various argillaceous rocks that are being considered for the deep geological disposal of radioactive waste, i.e. from plastic, soft, poorly indurated clays to brittle, hard mud-stones or shales. The Clay Club considered it necessary and timely to provide a catalogue to gather in a structured way the key geo-scientific characteristics of the various argillaceous formations that are - or were - studied in NEA member countries with regard to radioactive waste disposal. The present catalogue represents the outcomes of this Clay Club initiative. (author)

  20. Solid images generated from UAVs to analyze areas affected by rock falls

    Science.gov (United States)

    Giordan, Daniele; Manconi, Andrea; Allasia, Paolo; Baldo, Marco

    2015-04-01

    The study of rock fall affected areas is usually based on the recognition of principal joints families and the localization of potential instable sectors. This requires the acquisition of field data, although as the areas are barely accessible and field inspections are often very dangerous. For this reason, remote sensing systems can be considered as suitable alternative. Recently, Unmanned Aerial Vehicles (UAVs) have been proposed as platform to acquire the necessary information. Indeed, mini UAVs (in particular in the multi-rotors configuration) provide versatility for the acquisition from different points of view a large number of high resolution optical images, which can be used to generate high resolution digital models relevant to the study area. By considering the recent development of powerful user-friendly software and algorithms to process images acquired from UAVs, there is now a need to establish robust methodologies and best-practice guidelines for correct use of 3D models generated in the context of rock fall scenarios. In this work, we show how multi-rotor UAVs can be used to survey areas by rock fall during real emergency contexts. We present two examples of application located in northwestern Italy: the San Germano rock fall (Piemonte region) and the Moneglia rock fall (Liguria region). We acquired data from both terrestrial LiDAR and UAV, in order to compare digital elevation models generated with different remote sensing approaches. We evaluate the volume of the rock falls, identify the areas potentially unstable, and recognize the main joints families. The use on is not so developed but probably this approach can be considered the better solution for a structural investigation of large rock walls. We propose a methodology that jointly considers the Structure from Motion (SfM) approach for the generation of 3D solid images, and a geotechnical analysis for the identification of joint families and potential failure planes.

  1. Radiogeochemical characteristic of rocks of the Crimea peninsula and some principles of sedimentation

    International Nuclear Information System (INIS)

    Gherasimov, Yu.G.

    1983-01-01

    Radiogeochemical mapping with rock sampling of profiles, crossing all main structural facies zones of the Crimea peninsula was conducted. 1000 samples were taken. Uranium determination in samples was performed by fluorescence method (2 g/t threshold sensitivity). The distributions of U and Th background contents in rocks of the Crimea were tabulated. Maps of sampling of geological formations and distribution of U and Th background contents in rocks are given. It is shown that radioelement content in Crimea rocks is for the most part lower than clark one: 1.3-2.1 g/t contents prevail for U, Th contents don't exceed 12 g/t. Closeness of some radiogeochemical parameters points to the formation of terrigenous Crimea rocks due to removal of the material from the Ukrainian shield. Reworking of initial terrigenous material by hypergene processes led to U and Th separation, as well as to enrichment of younger sedimentary rocks with uranium

  2. ROCK-CAD - computer aided geological modelling system

    International Nuclear Information System (INIS)

    Saksa, P.

    1995-12-01

    The study discusses surface and solid modelling methods, their use and interfacing with geodata. Application software named ROCK-CAD suitable for geological bedrock modelling has been developed with support from Teollisuuden Voima Oy (TVO). It has been utilized in the Finnish site characterization programme for spent nuclear fuel waste disposal during the 1980s and 1990s. The system is based on the solid modelling technique. It comprises also rich functionality for the particular geological modelling scheme. The ROCK-CAD system provides, among other things, varying graphical vertical and horizontal intersections and perspective illustrations. The specially developed features are the application of the boundary representation modelling method, parametric object generation language and the discipline approach. The ROCK-CAD system has been utilized in modelling spatial distribution of rock types and fracturing structures in TVO's site characterization. The Olkiluoto site at Eurajoki serves as an example case. The study comprises the description of the modelling process, models and illustration examples. The utilization of bedrock models in site characterization, in tentative repository siting as well as in groundwater flow simulation is depicted. The application software has improved the assessment of the sites studied, given a new basis for the documentation of interpretation and modelling work, substituted hand-drawing and enabled digital transfer to numerical analysis. Finally, aspects of presentation graphics in geological modelling are considered. (84 refs., 30 figs., 11 tabs.)

  3. Validation of choice and determination of geotechnology parameters with regard to stress–strain state of rocks

    Science.gov (United States)

    Freidin, AM; Neverov, SA; Neverov, AA; Konurin, AI

    2018-03-01

    The paper illustrates efficiency and reliability of types of rock mass stress state conditioned by geological and structural features of rocks in design, selection and validation of geotechnology parameters. The authors of the paper present calculation of stresses in rock mass under sublevel stoping depending on the type of the geosphere and on the depth of the ore body occurrence.

  4. Assessment of arrays of in-stream tidal turbines in the Bay of Fundy.

    Science.gov (United States)

    Karsten, Richard; Swan, Amanda; Culina, Joel

    2013-02-28

    Theories of in-stream turbines are adapted to analyse the potential electricity generation and impact of turbine arrays deployed in Minas Passage, Bay of Fundy. Linear momentum actuator disc theory (LMADT) is combined with a theory that calculates the flux through the passage to determine both the turbine power and the impact of rows of turbine fences. For realistically small blockage ratios, the theory predicts that extracting 2000-2500 MW of turbine power will result in a reduction in the flow of less than 5 per cent. The theory also suggests that there is little reason to tune the turbines if the blockage ratio remains small. A turbine array model is derived that extends LMADT by using the velocity field from a numerical simulation of the flow through Minas Passage and modelling the turbine wakes. The model calculates the resulting speed of the flow through and around a turbine array, allowing for the sequential positioning of turbines in regions of strongest flow. The model estimates that over 2000 MW of power is possible with only a 2.5 per cent reduction in the flow. If turbines are restricted to depths less than 50 m, the potential power generation is reduced substantially, down to 300 MW. For large turbine arrays, the blockage ratios remain small and the turbines can produce maximum power with a drag coefficient equal to the Betz-limit value.

  5. High-resolution three-dimensional imaging and analysis of rock falls in Yosemite valley, California

    Science.gov (United States)

    Stock, Gregory M.; Bawden, G.W.; Green, J.K.; Hanson, E.; Downing, G.; Collins, B.D.; Bond, S.; Leslar, M.

    2011-01-01

    We present quantitative analyses of recent large rock falls in Yosemite Valley, California, using integrated high-resolution imaging techniques. Rock falls commonly occur from the glacially sculpted granitic walls of Yosemite Valley, modifying this iconic landscape but also posing signifi cant potential hazards and risks. Two large rock falls occurred from the cliff beneath Glacier Point in eastern Yosemite Valley on 7 and 8 October 2008, causing minor injuries and damaging structures in a developed area. We used a combination of gigapixel photography, airborne laser scanning (ALS) data, and ground-based terrestrial laser scanning (TLS) data to characterize the rock-fall detachment surface and adjacent cliff area, quantify the rock-fall volume, evaluate the geologic structure that contributed to failure, and assess the likely failure mode. We merged the ALS and TLS data to resolve the complex, vertical to overhanging topography of the Glacier Point area in three dimensions, and integrated these data with gigapixel photographs to fully image the cliff face in high resolution. Three-dimensional analysis of repeat TLS data reveals that the cumulative failure consisted of a near-planar rock slab with a maximum length of 69.0 m, a mean thickness of 2.1 m, a detachment surface area of 2750 m2, and a volume of 5663 ?? 36 m3. Failure occurred along a surfaceparallel, vertically oriented sheeting joint in a clear example of granitic exfoliation. Stress concentration at crack tips likely propagated fractures through the partially attached slab, leading to failure. Our results demonstrate the utility of high-resolution imaging techniques for quantifying far-range (>1 km) rock falls occurring from the largely inaccessible, vertical rock faces of Yosemite Valley, and for providing highly accurate and precise data needed for rock-fall hazard assessment. ?? 2011 Geological Society of America.

  6. In-stream measurements of combustion during Mach 5 to 7 tests of the Hypersonic Research Engine (HRE)

    Science.gov (United States)

    Lezberg, Erwin A.; Metzler, Allen J.; Pack, William D.

    1993-01-01

    Results of in-stream combustion measurements taken during Mach 5 to 7 true simulation testing of the Hypersonic Research Engine/Aerothermodynamic Integration Model (HRE/AIM) are presented. These results, the instrumentation techniques, and configuration changes to the engine installation that were required to test this model are described. In test runs at facility Mach numbers of 5 to 7, an exhaust instrumentation ring which formed an extension of the engine exhaust nozzle shroud provided diagnostic measurements at 10 circumferential locations in the HRE combustor exit plane. The measurements included static and pitot pressures using conventional conical probes, combustion gas temperatures from cooled-gas pyrometer probes, and species concentration from analysis of combustion gas samples. Results showed considerable circumferential variation, indicating that efficiency losses were due to nonuniform fuel distribution or incomplete mixing. Results using the Mach 7 facility nozzle but with Mach 6 temperature simulation, 1590 to 1670 K, showed indications of incomplete combustion. Nitric oxide measurements at the combustor exit peaked at 2000 ppmv for stoichiometric combustion at Mach 6.

  7. The Rock Cycle

    Science.gov (United States)

    Singh, Raman J.; Bushee, Jonathan

    1977-01-01

    Presents a rock cycle diagram suitable for use at the secondary or introductory college levels which separates rocks formed on and below the surface, includes organic materials, and separates products from processes. (SL)

  8. Water-rock interaction in a high-FeO olivine rock in nature

    International Nuclear Information System (INIS)

    Hellmuth, K.H.; Lindberg, A.; Tullborg, E.L.

    1992-12-01

    The long-term behaviour in nature of high-FeO olivine rock in contact with surface water has been studied at the Lovasjaervi instrusion, SE-Finland. The rock has been proposed as a high-capasity, higly reactive redox-buffer backfill in a repository for spent fuel. Favourable groundwater chemistry is a major parameter relevant to safety of such a repository. Reducing conditions favour the retardation of long-lived, redox-sensitive radionuclides. Weathering influences have been studied at the natural outcrop of the rock mass. The interaction of oxidizing surface waters with rock at greater depths has been studied by using fissure filling minerals. Investigation of weathered rock from the outcrop indicates that the olivine rock is highly reactive on a geological time scale and its redox capasity is available although the instrusion as a whole is surprisingly well preserved. The fissure fillings studied allow the conclusion that oxygen seems to be efficiently removed from intruding surface water. Oxidation seem to have caused visible effects only along very conducting fractures and near the contact zones of the surrounding granitic rock. Stable isotope data of fissure filling calcites indicate that the influence of surface waters can be traced clearly down to a depth of about 50 m, but also at greater depths re-equilibration has occurred. Groundwater data from the site were not available. (orig.)

  9. Anisotropy of strength and deformability of fractured rocks

    Directory of Open Access Journals (Sweden)

    Majid Noorian Bidgoli

    2014-04-01

    Full Text Available Anisotropy of the strength and deformation behaviors of fractured rock masses is a crucial issue for design and stability assessments of rock engineering structures, due mainly to the non-uniform and non-regular geometries of the fracture systems. However, no adequate efforts have been made to study this issue due to the current practical impossibility of laboratory tests with samples of large volumes containing many fractures, and the difficulty for controlling reliable initial and boundary conditions for large-scale in situ tests. Therefore, a reliable numerical predicting approach for evaluating anisotropy of fractured rock masses is needed. The objective of this study is to systematically investigate anisotropy of strength and deformability of fractured rocks, which has not been conducted in the past, using a numerical modeling method. A series of realistic two-dimensional (2D discrete fracture network (DFN models were established based on site investigation data, which were then loaded in different directions, using the code UDEC of discrete element method (DEM, with changing confining pressures. Numerical results show that strength envelopes and elastic deformability parameters of tested numerical models are significantly anisotropic, and vary with changing axial loading and confining pressures. The results indicate that for design and safety assessments of rock engineering projects, the directional variations of strength and deformability of the fractured rock mass concerned must be treated properly with respect to the directions of in situ stresses. Traditional practice for simply positioning axial orientation of tunnels in association with principal stress directions only may not be adequate for safety requirements. Outstanding issues of the present study and suggestions for future study are also presented.

  10. Sliding rocks on Racetrack Playa, Death Valley National Park: first observation of rocks in motion.

    Directory of Open Access Journals (Sweden)

    Richard D Norris

    Full Text Available The engraved trails of rocks on the nearly flat, dry mud surface of Racetrack Playa, Death Valley National Park, have excited speculation about the movement mechanism since the 1940s. Rock movement has been variously attributed to high winds, liquid water, ice, or ice flotation, but has not been previously observed in action. We recorded the first direct scientific observation of rock movements using GPS-instrumented rocks and photography, in conjunction with a weather station and time-lapse cameras. The largest observed rock movement involved > 60 rocks on December 20, 2013 and some instrumented rocks moved up to 224 m between December 2013 and January 2014 in multiple move events. In contrast with previous hypotheses of powerful winds or thick ice floating rocks off the playa surface, the process of rock movement that we have observed occurs when the thin, 3 to 6 mm, "windowpane" ice sheet covering the playa pool begins to melt in late morning sun and breaks up under light winds of -4-5 m/s. Floating ice panels 10 s of meters in size push multiple rocks at low speeds of 2-5 m/min. along trajectories determined by the direction and velocity of the wind as well as that of the water flowing under the ice.

  11. The Controls of Pore-Throat Structure on Fluid Performance in Tight Clastic Rock Reservoir: A Case from the Upper Triassic of Chang 7 Member, Ordos Basin, China

    Directory of Open Access Journals (Sweden)

    Yunlong Zhang

    2018-01-01

    Full Text Available The characteristics of porosity and permeability in tight clastic rock reservoir have significant difference from those in conventional reservoir. The increased exploitation of tight gas and oil requests further understanding of fluid performance in the nanoscale pore-throat network of the tight reservoir. Typical tight sandstone and siltstone samples from Ordos Basin were investigated, and rate-controlled mercury injection capillary pressure (RMICP and nuclear magnetic resonance (NMR were employed in this paper, combined with helium porosity and air permeability data, to analyze the impact of pore-throat structure on the storage and seepage capacity of these tight oil reservoirs, revealing the control factors of economic petroleum production. The researches indicate that, in the tight clastic rock reservoir, largest throat is the key control on the permeability and potentially dominates the movable water saturation in the reservoir. The storage capacity of the reservoir consists of effective throat and pore space. Although it has a relatively steady and significant proportion that resulted from the throats, its variation is still dominated by the effective pores. A combination parameter (ε that was established to be as an integrated characteristic of pore-throat structure shows effectively prediction of physical capability for hydrocarbon resource of the tight clastic rock reservoir.

  12. Linear geologic structure and magic rock discrimination as determined from infrared data

    Science.gov (United States)

    Offield, T. W.; Rowan, L. C.; Watson, R. D.

    1970-01-01

    Color infrared photographs of the Beartooth Mountains, Montana show the distribution of mafic dikes and amphibolite bodies. Lineaments that cross grassy plateaus can be identified as dikes by the marked constrast between the dark rocks and the red vegetation. Some amphibolite bodies in granitic terrain can also be detected by infrared photography and their contacts can be accurately drawn due to enchanced contrast of the two types of rock in the near infrared. Reflectance measurements made in the field for amphibolite and granite show that the granite is 25% to 50% more reflective in the near infrared than in the visible region. Further enhancement is due to less atmospheric scattering than in the visible region. Thermal infrared images of the Mill Creek, Oklahoma test site provided information on geologic faults and fracture systems not obtainable from photographs. Subtle stripes that cross outcrop and intervening soil areas and which probably record water distribution are also shown on infrared photographs.

  13. Review on the prevailing methods for the prediction of potential rock burst / rock spalling in tunnels

    OpenAIRE

    Panthi, Krishna Kanta

    2017-01-01

    Rock burst / rock spalling is among the prevailing stability challenges, which can be met while tunneling through hard rock mass. Especially, this is very relevant for the mountainous country like Norway where hard rock is dominating and many road, railway and hydropower tunnels have to be aligned deep into the mountain with steep valley slope topography. Tunnels passing beneath deep rock cover (overburden), in general, are subjected to high in-situ stresses. If the rock mass is relatively un...

  14. Geotechnical evaluation of rocks and soils in Catoca kimberlitic mining complex (Angola

    Directory of Open Access Journals (Sweden)

    Domingos M. Dos Santos Neves-Margarida

    2012-10-01

    Full Text Available Landslides and rock sliding occur very frequently in the mining area of Catoca, located in Angola. Therefore, a physical/mechanical and geotechnical characterization of the massif and the rock matrix was carried out adopting the landslide classifications as proposed by Hutchinson and Varnes. The safety factor was applied based on the structural weakness coefficient (λ; resulting in 0.70 in surface rocks, sandstones and intraformational sands; 0.58 in oversaturated eluvial gneiss; 0.50 in cracked gneiss and 0.47 in the ore compound of weathered, moist kimberlitic porphyric and weathered porphyric kimberlite. These results indicate the low strength of the massif and the need to reformulate the activities in the mine and the construction of more stable slopes. It could also be observed that deformation of rocks in the slopes and the cuts in the Catoca mine is conditioned by the movement of underground water within the rock massif itself.

  15. Influence of Fissure Number on the Mechanical Properties of Layer-Crack Rock Models under Uniaxial Compression

    Directory of Open Access Journals (Sweden)

    Yun-liang Tan

    2018-01-01

    Full Text Available Many case studies have revealed that rock bursts generally occur in the high stress concentration area where layer-crack structures often exist, especially for brittle coal or rock masses. Understanding the mechanical properties of layer-crack rock models is beneficial for rational design and stability analysis of rock engineering project and rock burst prevention. This study experimentally investigated the influence of fissure number on the mechanical properties of layer-crack rock models through uniaxial compression tests. The digital speckle correlation method (DSCM and acoustic emission (AE techniques were applied to record and analyze the information of deformation and failure processes. Test results show the following: the bearing capacity of layer-crack specimen decreases compared with intact specimen, but their failure modes are similar, which are the splitting failure accompanied with local shear failure; the nonuniform deformation phenomenon begins to appear at the elastic deformation stage for layer-crack specimens; the AE behavior of intact specimens consists of three stages, that is, active stage, quiet stage, and major active stage, but for layer-crack specimens, it is characteristic by three peaks without quiet stage. In addition, as the fissure number of layer-crack specimens increases, the bearing capacity of specimens decreases, the appearing time of nonuniform deformation phenomenon in the specimen surface decreases, the AE events are denser and denser in each peak stage, and the risk of dynamic instability of layer-crack structure increases. At last, the failure mechanism of layer-crack structure and the related mitigation advices were discussed based on the test results. In general, the novelty is that this paper focuses on the failure mechanism of layer-crack structure directly.

  16. Novel ROCK inhibitors for the treatment of pulmonary arterial hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, Duncan; Hollingworth, Greg; Soldermann, Nicolas; Sprague, Elizabeth; Schuler, Walter; Vangrevelinghe, Eric; Duggan, Nicholas; Thomas, Matthew; Kosaka, Takatoshi; Waters, Nigel; van Eis, Maurice J. (Novartis)

    2014-10-01

    A novel class of selective inhibitors of ROCK1 and ROCK2 has been identified by structural based drug design. PK/PD experiments using a set of highly selective Rho kinase inhibitors suggest that systemic Rho kinase inhibition is linked to a reversible reduction in lymphocyte counts. These results led to the consideration of topical delivery of these molecules, and to the identification of a lead molecule 7 which shows promising PK and PD in a murine model of pulmonary hypertension after intra-tracheal dosing.

  17. Synthetic Rock Analogue for Permeability Studies of Rock Salt with Mudstone

    Directory of Open Access Journals (Sweden)

    Hongwu Yin

    2017-09-01

    Full Text Available Knowledge about the permeability of surrounding rock (salt rock and mudstone interlayer is an important topic, which acts as a key parameter to characterize the tightness of gas storage. The goal of experiments that test the permeability of gas storage facilities in rock salt is to develop a synthetic analogue to use as a permeability model. To address the permeability of a mudstone/salt layered and mixed rock mass in Jintan, Jiangsu Province, synthetic mixed and layered specimens using the mudstone and the salt were fabricated for permeability testing. Because of the gas “slippage effect”, test results are corrected by the Klinkenberg method, and the permeability of specimens is obtained by regression fitting. The results show that the permeability of synthetic pure rock salt is 6.9 × 10−20 m2, and its porosity is 3.8%. The permeability of synthetic mudstone rock is 2.97 × 10−18 m2, with a porosity 17.8%. These results are close to those obtained from intact natural specimens. We also find that with the same mudstone content, the permeability of mixed specimens is about 40% higher than for the layered specimens, and with an increase in the mudstone content, the Klinkenberg permeability increases for both types of specimens. The permeability and mudstone content have a strong exponential relationship. When the mudstone content is below 40%, the permeability increases only slightly with mudstone content, whereas above this threshold, the permeability increases rapidly with mudstone content. The results of the study are of use in the assessment of the tightness of natural gas storage facilities in mudstone-rich rock salt formations in China.

  18. Geologic history of the Slick Rock district and vicinity, San Miguel and Dolores Counties, Colorado

    International Nuclear Information System (INIS)

    Shawe, D.R.

    1976-01-01

    This report is a narrative summary and interpretation, in the form of a geologic history of the Slick Rock district and vicinity, of four previously published chapters in this series dealing with stratigraphy of the Slick Rock district and vicinity, petrography of sedimentary rocks of the district, structure of the district and vicinity, and altered sedimentary rocks of the district, and of other previously published reports on the district. It forms the background, with the earlier reports, for presentation of a final report in the series describing the uranium-vanadium ore deposits. A review of the origin of sedimentary rocks and geologic history of the region indicates that formation of uranium-vanadium deposits was a natural result of the deposition of th rocks, the occurrence of intrastratal waters therein, and the post-depositional movement of the waters resulting from evolution of the sedimentary rock environment. 31 refs

  19. 'Mister Badger' Pushing Mars Rock

    Science.gov (United States)

    1976-01-01

    Viking's soil sampler collector arm successfully pushed a rock on the surface of Mars during the afternoon of Friday, October 8. The irregular-shaped rock was pushed several inches by the Lander's collector arm, which displaced the rock to the left of its original position, leaving it cocked slightly upward. Photographs and other information verified the successful rock push. Photo at left shows the soil sampler's collector head pushing against the rock, named 'Mister Badger' by flight controllers. Photo at right shows the displaced rock and the depression whence it came. Part of the soil displacement was caused by the collector s backhoe. A soil sample will be taken from the site Monday night, October 11. It will then be delivered to Viking s organic chemistry instrument for a series of analyses during the next few weeks. The sample is being sought from beneath a rock because scientists believe that, if there are life forms on Mars, they may seek rocks as shelter from the Sun s intense ultraviolet radiation.

  20. Evaluation of Management of Water Releases for Painted Rocks Rexervoir, Bitterroot River, Montana, 1985 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Lere, Mark E. (Montana Department of Fish, Wildlife and Parks, Missoula, MT)

    1985-12-01

    The Bitterroot River, located in western Montana, is an important and heavily used resource, providing water for agriculture and a source for diversified forms of recreation. Water shortages in the river, however, have been a persistent problem for both irrigators and recreational users. Five major diversions and numerous smaller canals remove substantial quantities of water from the river during the irrigation season. Historically, the river has been severely dewatered between the towns of Hamilton and Stevensville as a result of these withdrawals. Demands for irrigation water from the Bitterroot River have often conflicted with the instream flow needs for trout. Withdrawals of water can decrease suitable depths, velocities, substrates and cover utilized by trout (Stalnaker and Arnette 1976, Wesche 1976). Losses in habitat associated with dewatering have been shown to diminish the carrying capacities for trout populations (Nelson 1980). Additionally, dewatering of the Bitterroot River has forced irrigators to dike or channelize the streambed to obtain needed flows. These alterations reduce aquatic habitat and degrade channel stability. Odell (personal communication) found a substantial reduction in the total biomass of aquatic insects within a section of the Bitterroot River that had been bulldozed for irrigation purposes. The Montana Department of Fish, Wildlife and Parks (MDFWP) has submitted a proposal to the Northwest Power Planning Council for the purchase of 10,000 acre-feet (AF) of stored water in Painted Rocks Reservoir to augment low summer flows in the Bitterroot River. This supplemental water potentially would enhance the fishery in the river and reduce degradation of the channel due to diversion activities. The present study was undertaken to: (1) develop an implementable water management plan for supplemental releases from Painted Rocks Reservoir which would provide optimum benefits to the river: (2) gather fisheries and habitat information to

  1. Response spectra by blind faults for design purpose of stiff structures on rock site

    International Nuclear Information System (INIS)

    Hiroyuki Mizutani; Kenichi Kato; Masayuki Takemura; Kazuhiko Yashiro; Kazuo Dan

    2005-01-01

    The goal of this paper is to propose the response spectra by blind faults for seismic design of nuclear power facilities. It is impossible to evaluate earthquake ground motions from blind faults, because the size and the location of blind fault cannot be identified even if the detailed geological surveys are conducted. From the viewpoint of seismic design, it is crucial to investigate the upper level of earthquake ground motions due to blind faults. In this paper, 41 earthquakes that occurred in the upper crust in Japan and California are selected and classified into the active and the blind fault types. On the basis of near-source strong motion records observed on rock sites, upper level of response spectra by blind faults is examined. The estimated upper level is as follows: the peak ground acceleration is 450 cm/s 2 , the flat level of the acceleration response spectra is 1200 cm/s 2 , and the flat level of the velocity response spectra is 100 cm/s on rock sites with shear wave velocity Vs of about 700 m/s. The upper level can envelop the observed response spectra in near-source region on rock sites. (authors)

  2. An Illustration of Determining Quantitatively the Rock Mass Quality Parameters of the Hoek-Brown Failure Criterion

    Science.gov (United States)

    Wu, Li; Adoko, Amoussou Coffi; Li, Bo

    2018-04-01

    In tunneling, determining quantitatively the rock mass strength parameters of the Hoek-Brown (HB) failure criterion is useful since it can improve the reliability of the design of tunnel support systems. In this study, a quantitative method is proposed to determine the rock mass quality parameters of the HB failure criterion, namely the Geological Strength Index (GSI) and the disturbance factor ( D) based on the structure of drilling core and weathering condition of rock mass combined with acoustic wave test to calculate the strength of rock mass. The Rock Mass Structure Index and the Rock Mass Weathering Index are used to quantify the GSI while the longitudinal wave velocity ( V p) is employed to derive the value of D. The DK383+338 tunnel face of Yaojia tunnel of Shanghai-Kunming passenger dedicated line served as illustration of how the methodology is implemented. The values of the GSI and D are obtained using the HB criterion and then using the proposed method. The measured in situ stress is used to evaluate their accuracy. To this end, the major and minor principal stresses are calculated based on the GSI and D given by HB criterion and the proposed method. The results indicated that both methods were close to the field observation which suggests that the proposed method can be used for determining quantitatively the rock quality parameters, as well. However, these results remain valid only for rock mass quality and rock type similar to those of the DK383+338 tunnel face of Yaojia tunnel.

  3. Hydrocarbon potential of Ordovician and Silurian rocks. Siljan Region (Sweden)

    Energy Technology Data Exchange (ETDEWEB)

    Berner, U. [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Hannover (Germany); Lehnert, O. [Erlangen-Nuernberg Univ., Erlangen (Germany); Meinhold, G. [Goettingen Univ. (Germany)

    2013-08-01

    Hydrocarbon exploration in the vicinity of Europe's largest impact structure (Siljan, Central Sweden) focused for years on abiogenic concepts and largely neglected state of the art knowledge on hydrocarbon generation via thermal decomposition of organic matter. In our study we use sedimentary rocks obtained from three drill sites (Mora001, Stumsnaes 1 and Solberga 1) within the ring structure around the central uplift to investigate the hydrocarbon potential of Ordovician and Silurian strata of the region and also for comparison with the shale oil and gas potential of age equivalent rocks of the Baltic Sea. Elemental analyses provided information on concentrations of carbonate and organic carbon, total sulfur as well as on the composition of major and minor elements of the sediments. The data has been used to evaluate the depositional environment and possible diagenetic alterations of the organic matter. RockEval pyrolysis and solvent hydrocarbon extraction gave insight into the hydrocarbon generation potential and the type and thermal maturity of the sediments. From the geochemistry data of the studied wells it is obvious that changes of depositional environments (lacustrine - marine) have occurred during Ordovician and Silurian times. Although, the quality of the organic matter has been influenced in marine and brackish environments through sulfate reduction, we observe for a number of marine and lacustrine sediments a good to excellent preservation of the biological precursors which qualify the sediments as hydrocarbon source rocks (Type II kerogens). Lacustrine source rocks show a higher remaining hydrocarbon potential (up to {proportional_to}550 mg HC per g C{sub org}) than those of marine or brackish environments. Our investigations indicate that the thermal maturity of organic matter of the drill sites has reached the initial stage of oil generation. However, at Mora001 some of the sediments were stained with oil indicating that hydrocarbons have

  4. Source rock

    Directory of Open Access Journals (Sweden)

    Abubakr F. Makky

    2014-03-01

    Full Text Available West Beni Suef Concession is located at the western part of Beni Suef Basin which is a relatively under-explored basin and lies about 150 km south of Cairo. The major goal of this study is to evaluate the source rock by using different techniques as Rock-Eval pyrolysis, Vitrinite reflectance (%Ro, and well log data of some Cretaceous sequences including Abu Roash (E, F and G members, Kharita and Betty formations. The BasinMod 1D program is used in this study to construct the burial history and calculate the levels of thermal maturity of the Fayoum-1X well based on calibration of measured %Ro and Tmax against calculated %Ro model. The calculated Total Organic Carbon (TOC content from well log data compared with the measured TOC from the Rock-Eval pyrolysis in Fayoum-1X well is shown to match against the shale source rock but gives high values against the limestone source rock. For that, a new model is derived from well log data to calculate accurately the TOC content against the limestone source rock in the study area. The organic matter existing in Abu Roash (F member is fair to excellent and capable of generating a significant amount of hydrocarbons (oil prone produced from (mixed type I/II kerogen. The generation potential of kerogen in Abu Roash (E and G members and Betty formations is ranging from poor to fair, and generating hydrocarbons of oil and gas prone (mixed type II/III kerogen. Eventually, kerogen (type III of Kharita Formation has poor to very good generation potential and mainly produces gas. Thermal maturation of the measured %Ro, calculated %Ro model, Tmax and Production index (PI indicates that Abu Roash (F member exciting in the onset of oil generation, whereas Abu Roash (E and G members, Kharita and Betty formations entered the peak of oil generation.

  5. Contribution To The Geology Of Basement Rocks In The South Western Desert Of Egypt

    International Nuclear Information System (INIS)

    Sadek, M.F.; Khyamy, A.A.

    2003-01-01

    Three major Precambrian basement inliers are exposed in the South Western Desert of Egypt between Long. 29 degree E and the River Nile within the Uweinat-Bir Safsaf-Aswan E-W uplift system. These are Bir Safsaf, Gabal EI-Asr and Gabal Umm Shaghir areas. Smaller outcrops include Gabal EI-Gara El-Hamra and Gabal El-Gara EI-Soda, Gabal Siri, GabaI EI-Fantas and Aswan-Kalabsha area as well as the scattered outcrops around Darb El-Arbain road. Band ratios 5/7, 5/1, 4 of Landsat TM images were applied to delineate the borders, the lithologic units and structural features of low relief basement outcrops within the surrounding flat lying sedimentary rocks and sand plains. These basement rocks comprise ortho gneisses (assumed by many authors as related to old continent pre Pan-African rocks), G 1 tonalite-granodiorite, and G2 monzogranite-alkali feldspar granite intruded by variable dykes. The boundaries between the basement exposures and the sedimentary rocks are marked by nonconformity surfaces or sets of faults. Both basement and sedimentary rocks are intruded by Mesozoic syenite-G3 granites, rhyolite, trachytic plugs and Upper Cretaceous to Tertiary basalts. The basement exposures are structurally controlled by major E- W fault systems. Their vertical uplifting is overprinted by folding the overlying sedimentary rocks. This study revealed that, the different basement exposures in the SE of the Western Desert of Egypt are similar in appearance and field relations to the Pan-African basement rocks extending towards the east of the River Nile and exposed everywhere in the Eastern Desert of Egypt

  6. Interim rock mass properties and conditions for analyses of a repository in crystalline rock

    International Nuclear Information System (INIS)

    Tammemagi, H.Y.; Chieslar, J.D.

    1985-03-01

    A summary of rock properties for generic crystalline rock is compiled from literature sources to provide the input data for analyses of a conceptual repository in crystalline rock. Frequency histograms, mean values and ranges of physical, mechanical, thermal, and thermomechanical properties, and the dependence of these properties on temperature are described. A description of the hydrogeologic properties of a crystalline rock mass and their dependence on depth is provided. In addition, the temperature gradients, mean annual surface temperature, and in situ stress conditions are summarized for the three regions of the United States currently under consideration to host a crystalline repository; i.e., the North Central, Northeastern, and Southeastern. Brief descriptions of the regional geology are also presented. Large-scale underground experiments in crystalline rock at Stripa, Sweden, and in Climax Stock in Nevada, are reviewed to assess whether the rock properties presented in this report are representative of in situ conditions. The suitability of each rock property and the sufficiency of its data base are described. 110 refs., 27 figs., 4 tabs

  7. Basic rocks in Finland

    International Nuclear Information System (INIS)

    Piirainen, T.; Gehoer, S.; Iljina, M.; Kaerki, A.; Paakkola, J.; Vuollo, J.

    1992-10-01

    Basic igneous rocks, containing less than 52% SiO 2 , constitute an important part of the Finnish Archaean and Proterozoic crust. In the Archaean crust exist two units which contain the majority of the basic rocks. The Arcaean basic rocks are metavolcanics and situated in the Greenstone Belts of Eastern Finland. They are divided into two units. The greenstones of the lower one are tholeiites, komatiites and basaltic komatiites. The upper consists of bimodal series of volcanics and the basic rocks of which are Fe-tholeiites, basaltic komatiites and komatiites. Proterozoic basic rocks are divided into seven groups according to their ages. The Proterozoic igneous activity started by the volominous basic magmatism 2.44 Ga ago. During this stage formed the layered intrusions and related dykes in the Northern Finland. 2.2 Ga old basic rocks are situated at the margins of Karelian formations. 2.1 Ga aged Fe-tholeiitic magmatic activity is widespread in Eastern and Northern Finland. The basic rocks of 1.97 Ga age group are met within the Karelian Schist Belts as obducted ophiolite complexes but they occur also as tholeiitic diabase dykes cutting the Karelian schists and Archean basement. The intrusions and the volcanics of the 1.9 Ga old basic igneous activity are mostly encountered around the Granitoid Complex of Central Finland. Subjotnian, 1.6 Ga aged tholeiitic diabases are situated around the Rapakivi massifs of Southern Finland, and postjotnian, 1.2 Ga diabases in Western Finland where they form dykes cutting Svecofennian rocks

  8. Pore-scale analysis of electrical properties in thinly bedded rock using digital rock physics

    International Nuclear Information System (INIS)

    Sun, Jianmeng; Zhao, Jianpeng; Liu, Xuefeng; Chen, Hui; Jiang, LiMing; Zhang, JinYan

    2014-01-01

    We investigated the electrical properties of laminated rock consist of macro-porous layers and micro-porous layers based on digital rock technology. Due to the bedding effect and anisotropy, traditional Archie equations cannot well describe the electrical behavior of laminated rock. The RI-Sw curve of laminated rock shows a nonlinear relationship. The RI-Sw curve can be divided into two linear segments with different saturation exponent. Laminated sand-shale sequences and laminated sands of different porosity or grain size will yield macroscopic electrical anisotropy. Numerical simulation and theoretical analysis lead to the conclusion that electrical anisotropy coefficient of laminated rock is a strong function of water saturation. The function curve can be divided into three segments by the turning point. Therefore, the electrical behavior of laminated rock should be considered in oil exploration and development. (paper)

  9. Hillslope evolution in landscapes dominated by layered rocks

    Science.gov (United States)

    Glade, R.; Anderson, R. S.

    2016-12-01

    Geologic structure and lithology can exert fundamental control over hillslope evolution. Landforms common across the western US, such as mesas, hogbacks, flatirons, and symmetric ridges bounding dikes, develop in the face of differential weathering of layered rocks in a horizontal, tilted, or vertical structural orientation. These features exhibit a characteristic form distinct from that of homogeneous, soil-mantled hillslopes; linear-to-concave up slopes developed on soft underlying rock typically display a thin, non-uniform layer of mobile regolith and are armored by debris derived from the resistant layers. Feedbacks between weathering and transport of both easily eroded rock and embedded resistant material can explain this general form where debris is dominated by large resistant blocks. In the more general case, however, relationships between the size distribution of the resistant material, relative weathering rates, and boundary condition history are not well-understood. Here we use a 1-D numerical model to explore the evolution of two end-member landforms: a hogback associated with a tilted sandstone bed, and a symmetrical ridge associated with a vertical basalt dike, both bounded by shale bedrock. The first, modeled after the Dakota Hogback near Boulder, Colorado, produces large sandstone blocks that both armor the underlying slope from weathering and stall regolith motion. The vertical dike, modeled after Shiprock, New Mexico, produces both large blocks and small basalt chips that armor the bounding slopes. We show that in both settings, feedbacks between armor and soft rock lead to autogenic processes that modulate base level signals, alter hillslope form, and increase relief over time when compared to a control case with no armor. We explore a variety of boundary conditions in which the presence of these feedbacks leads to a quasi-steady state hillslope form that differs both quantitatively and qualitatively from that expected of a traditional parabolic

  10. Depositional environment and source rock potential of Cenomanian and Turonian sedimentary rocks of the Tarfaya Basin, Southwest Morocco

    Energy Technology Data Exchange (ETDEWEB)

    Ghassal, B.I.; Littke, R.; Sachse, V.; Sindern, S.; Schwarzbauer, J.

    2016-07-01

    from bituminite-fair to bituminite-rich and to higher percentages of visible organic matter towards the younger interval. These differences in the organic matter type are attributed to i) early diagenetic kerogen sulfurization and ii) the upwelling depositional environment. Moreover, kerogen sulfurization was controlled by the relationship between carbonate, iron and sulfur as well as the organic matter. Thus, the organic carbon-rich deposits can be grouped into: i) low Sorg and moderately organic matter-rich oil prone source rocks, ii) moderate Sorg and organic-carbon-rich oil prone source rocks, iii) high Sorg and organic carbon-rich oil prone source rocks and iv) very high Sorg and organic carbon-rich oil prone source rocks, the latter representing the CTBE interval. Types 2 to 4 will generate sulfur-rich petroleum upon maturation or artificial oil shale retorting. This integrated organic and inorganic approach sheds light on the various processes leading to the development of the world-class oil shales deposited through the Cenomanian to Turonian. In addition, this study shows how the changes in the depositional environment might have controlled kerogen sulfurization and organic matter preservation and structure. This detailed approach provides a better understanding on source rock development during the Cenomanian to Turonian in a global context, as many of the geochemical features were identified worldwide for deposits related to OAE2. (Author)

  11. Pb, Sr and Nd isotope geological characteristics and its evolution of Jianchaling rock

    International Nuclear Information System (INIS)

    Pang Chunyong; Chen Minyang; Xu Wenxin

    2003-01-01

    It has been a long time debatable subject on the raw material source and its genesis of Jianchaling ultrabasic rock, because the original rock phases, the original mineral compositions, texture and structure, even part of the chemical components of the rocks had been changed completely after many periods and phases of metamorphism. According to the content of Pb, Rb, Sr, Nd elements and their Pb, Sr, Nd isotope compositions of the rocks, together with the isotope geological age of late magmatic activities, the authors analyze the evolution of Pb, Sr, Nd isotope compositions, The inferred initiate Nd isotope ratio of ultrabasic rocks is 0.510233, lower than that of meteorite unity at a corresponding period, its ε Nd(T)>O; The initiate Sr ratios inferred by the isotope geological age ranges from 0.702735 to 0.719028; Projecting the lead isotope compositions on the Pb tectonic evolution model, the result indicates that the raw material of Jianchaling ultrabasic rock coming from the deplete upper mantle. The ultrabasic magma which enrich of Mg, Ni and less S intruded the crust and formed the Jianchaling ultrabasic rock at late Proterozoic era (927 Ma±). The forming time of serpentinite is mostly equal to the granitoid intruding time, showing the intrusion o flate acidic magma caused a large scale alteration of the ultrabasic rocks and formed the meta-ultrabasic phase rock observed today. (authors)

  12. Triaxial slide-hold-slide shear experiment of sedimentary rock under drain condition

    International Nuclear Information System (INIS)

    Kishida, Kiyoshi; Yano, Takao; Elsworth, Derek; Yasuhara, Hideaki; Nakashima, Shinichiro

    2011-01-01

    When discussing the mechanical and hydro-mechanical properties of rock masses under the long-term holding, the variation of rock structure and the change of shear band condition should be discussed in considering the effect of thermal and chemical influences. In this research, the triaxial shear experiment under drain condition was conducted through sedimentary rock, and in the residual stress state, the slide-hold-slide processes were applied to these triaxial experiments. The experiments were carried out in 3 kinds of confining conditions and 2 kinds of thermal conditions. Consequently, the healing phenomena can be observed and the shear strength recovery is also confirmed in process of the holding time. (author)

  13. Dendritic network models: Improving isoscapes and quantifying influence of landscape and in-stream processes on strontium isotopes in rivers

    Science.gov (United States)

    Brennan, Sean R.; Torgersen, Christian E.; Hollenbeck, Jeff P.; Fernandez, Diego P.; Jensen, Carrie K.; Schindler, Daniel E.

    2016-05-01

    A critical challenge for the Earth sciences is to trace the transport and flux of matter within and among aquatic, terrestrial, and atmospheric systems. Robust descriptions of isotopic patterns across space and time, called "isoscapes," form the basis of a rapidly growing and wide-ranging body of research aimed at quantifying connectivity within and among Earth's systems. However, isoscapes of rivers have been limited by conventional Euclidean approaches in geostatistics and the lack of a quantitative framework to apportion the influence of processes driven by landscape features versus in-stream phenomena. Here we demonstrate how dendritic network models substantially improve the accuracy of isoscapes of strontium isotopes and partition the influence of hydrologic transport versus local geologic features on strontium isotope ratios in a large Alaska river. This work illustrates the analytical power of dendritic network models for the field of isotope biogeochemistry, particularly for provenance studies of modern and ancient animals.

  14. Biodiversity in intertidal rock pools: informing engineering criteria for artificial habitat enhancement in the built environment.

    Science.gov (United States)

    Firth, Louise B; Schofield, Meredith; White, Freya J; Skov, Martin W; Hawkins, Stephen J

    2014-12-01

    Coastal defence structures are proliferating to counter rising and stormier seas. With increasing concern about the ecological value of built environments, efforts are being made to create novel habitat to increase biodiversity. Rock pools are infrequent on artificial structures. We compared biodiversity patterns between rock pools and emergent rock and assessed the role of pool depth and substratum incline in determining patterns of biodiversity. Rock pools were more taxon rich than emergent substrata. Patterns varied with depth and incline with algal groups being more positively associated with shallow than deeper habitats. Substratum incline had little influence on colonising epibiota, with the exception of canopy algae in deeper habitats where vertical surfaces supported greater taxon richness than horizontal surfaces. The creation of artificial rock pools in built environments will have a positive effect on biodiversity. Building pools of varying depths and inclines and shore heights will provide a range of habitats, increase environmental heterogeneity, therefore creating more possible ecological niches, promoting local biodiversity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Research into basic rocks types

    International Nuclear Information System (INIS)

    1993-06-01

    Teollisuuden Voima Oy (TVO) has carried out research into basic rock types in Finland. The research programme has been implemented in parallel with the preliminary site investigations for radioactive waste disposal in 1991-1993. The program contained two main objectives: firstly, to study the properties of the basic rock types and compare those with the other rock types under the investigation; secondly, to carry out an inventory of rock formations consisting of basic rock types and suitable in question for final disposal. A study of environmental factors important to know regarding the final disposal was made of formations identified. In total 159 formations exceeding the size of 4 km 2 were identified in the inventory. Of these formations 97 were intrusive igneous rock types and 62 originally extrusive volcanic rock types. Deposits consisting of ore minerals, industrial minerals or building stones related to these formations were studied. Environmental factors like natural resources, protected areas or potential for restrictions in land use were also studied

  16. Investigations of some rock stress measuring techniques and the stress field in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Hanssen, Tor Harald

    1998-12-31

    Rock stresses are important to the safe construction and operation of all man-made structures in rock, whether In mining, civil or petroleum engineering. The crucial issue is their relative magnitude and orientation. This thesis develops equipment and methods for further rock stress assessment and reevaluates existing overcoring rock stress measurements, and relates this information to the present geological setting. Both laboratory work and field work are involved. In the field, rock stresses are measured by the overcoring and the hydraulic fracturing technique. An observation technique for assessing likely high stresses is developed. The field data refer to several hydropower projects and to some offshore hydrocarbon fields. The principal sections are: (1) Tectonic setting in the western Fennoscandia, (2) Triaxial rock stress measurements by overcoring using the NTH cell (a strain gauge cell developed at the Norwegian technical university in Trondheim and based on the CSIR cell of the South African Council for Scientific and Industrial Research), (3) Laboratory testing of the NTH cell, (4) Quality ranking of stresses measured by the NTH cell, (4) Recalculated rock stresses and implications to the regional stress field, (5) Hydraulic fracturing stress measurements. 113 refs., 98 figs., 62 tabs.

  17. Investigations of some rock stress measuring techniques and the stress field in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Hanssen, Tor Harald

    1997-12-31

    Rock stresses are important to the safe construction and operation of all man-made structures in rock, whether In mining, civil or petroleum engineering. The crucial issue is their relative magnitude and orientation. This thesis develops equipment and methods for further rock stress assessment and reevaluates existing overcoring rock stress measurements, and relates this information to the present geological setting. Both laboratory work and field work are involved. In the field, rock stresses are measured by the overcoring and the hydraulic fracturing technique. An observation technique for assessing likely high stresses is developed. The field data refer to several hydropower projects and to some offshore hydrocarbon fields. The principal sections are: (1) Tectonic setting in the western Fennoscandia, (2) Triaxial rock stress measurements by overcoring using the NTH cell (a strain gauge cell developed at the Norwegian technical university in Trondheim and based on the CSIR cell of the South African Council for Scientific and Industrial Research), (3) Laboratory testing of the NTH cell, (4) Quality ranking of stresses measured by the NTH cell, (4) Recalculated rock stresses and implications to the regional stress field, (5) Hydraulic fracturing stress measurements. 113 refs., 98 figs., 62 tabs.

  18. Evaluation of Rock Bolt Support for Polish Hard Rock Mines

    Science.gov (United States)

    Skrzypkowski, Krzysztof

    2018-03-01

    The article presents different types of rock bolt support used in Polish ore mining. Individual point resin and expansion rock bolt support were characterized. The roof classes for zinc and lead and copper ore mines were presented. Furthermore, in the article laboratory tests of point resin rock bolt support in a geometric scale of 1:1 with minimal fixing length of 0.6 m were made. Static testing of point resin rock bolt support were carried out on a laboratory test facility of Department of Underground Mining which simulate mine conditions for Polish ore and hard coal mining. Laboratory tests of point resin bolts were carried out, especially for the ZGH Bolesław, zinc and lead "Olkusz - Pomorzany" mine. The primary aim of the research was to check whether at the anchoring point length of 0.6 m by means of one and a half resin cartridge, the type bolt "Olkusz - 20A" is able to overcome the load.The second purpose of the study was to obtain load - displacement characteristic with determination of the elastic and plastic range of the bolt. For the best simulation of mine conditions the station steel cylinders with an external diameter of 0.1 m and a length of 0.6 m with a core of rock from the roof of the underground excavations were used.

  19. Thermal history of rocks in southern San Joaquin Valley, California: evidence from fission-track analysis

    Science.gov (United States)

    Naeser, N.D.; Naeser, C.W.; McCulloh, T.H.

    1990-01-01

    Fission-track analysis has been used to study the thermal and depositional history of the subsurface Tertiary sedimentary rocks on both sides of the active White Wolf reverse fault in the southern San Joaquin Valley. The distinctly different thermal histories of the rocks in the two structural blocks are clearly reflected in the apatite fission-track data, which suggest that rocks in the rapidly subsiding basin northwest of the fault have been near their present temperature for only about 1 m.y. compared with about 10 m.y. for rocks southeast of the fault. These estimates of heating time agree with previous estimates for these rocks. Zircon fission-track data indicate that the Tertiary sediments were derived from parent rocks of more than one age. However, from at least the Eocene to late Miocene or Pliocene, the major sediment source was rocks related to the youngest Sierra Nevada Mesozoic intrusive complexes, which are presently exposed east and south of the southern San Joaquin Valley. -from Authors

  20. Application of an Integrated and Self-contained Electromagnetic Acoustic Recorder for Monitoring the Rock Mass Structure and Development of Geodynamic Processes in Ore Mines

    Directory of Open Access Journals (Sweden)

    Bespal’ko Anatoly

    2016-01-01

    Full Text Available The paper presents a block diagram of the recorder of electromagnetic and acoustic signals. The recorder provides monitoring of electromagnetic and acoustic signals under changing stress-strain state of heterogeneous materials and rocks. The analog amplifier input sensitivity of electromagnetic signals in 4 channels is 10 μV, that of the electromagnetic signal intensity is 10 μ and that of acoustic signals is 50 μV. The operating frequency range of recording is (1÷100 kHz. The averaging of electromagnetic and acoustic signal amplitudes is performed within 1 or 5 seconds. The data on electromagnetic and acoustic emission materials is recorded in digital format in the internal memory of the recorder. The recorder operates off-line within 7 days. Repeated testing of the recorder in natural conditions of the Tashtagol mine showed that the changes in the amplitude and frequency parameters of electromagnetic signals (EMC indicate the structural damage in mines made of rocks which differ in their electrical properties. Measurements of the intensity of electromagnetic signals enable monitoring the changes in the stress-strain state of rocks during and after blasting and other geodynamic phenomena.

  1. Where the rubber meets the road: long-term in-stream data collection to inform regional land management monitoring in the Pacific Northwest

    Science.gov (United States)

    Hirsch, C.

    2017-12-01

    The initiation of the Northwest Forest Plan (NWFP) in 1994 brought a sea change to federal land management agencies of the Pacific Northwest. The NWFP was developed in response to the listing of the Northern Spotted Owl and concern about declining populations of Pacific Salmon. The Aquatic and Riparian Effectiveness Monitoring Program (AREMP) was developed to track changes that occurred as a result of active and passive management on the landscape. A significant management change affecting riparian areas was the creation of buffers around fish bearing and non-fish bearing streams. Two monitoring arms of the AREMP program focus on upslope and in-stream conditions in order to capture watershed-scale effects of land management changes. Field data to support the in-stream monitoring mission of AREMP began in 2002 with a study design based on an 8-year re-survey rotation. The sampling design was intended to capture watershed-scale variability across the broad and diverse study area in western Washington, western Oregon, and northwest California. 2017 marks repeat visits of every site and opens the door to more detailed assessments of changes that have occurred at local and regional extents over this time period. Results so far show improving trends in characteristics such as water temperature and macroinvertebrate community diversity. Maintaining an ongoing and relevant monitoring program over time has required a strong commitment to quality control in terms of data collection and analysis, and an openness to how AREMP can provide management relevant information as new challenges occur. AREMP's mandated role as the aquatic monitoring arm of the NWFP provides the overarching framework within which the program operates. However, new emerging topics of relevance to aquatic managers such as climate change and aquatic invasive species have been rolled into the mission over time. By being responsive to new challenges, and providing consistent feedback, AREMP has been able to

  2. Igneous Rocks

    Science.gov (United States)

    Doe, Bruce R.

    “Igneous Rocks was written for undergraduate geology majors who have had a year of college-level chemistry and a course in mineralogy … and for beginning graduate students. Geologists working in industry, government, or academia should find this text useful as a guide to the technical literature up to 1981 and as an overview of topics with which they have not worked but which may have unanticipated pertinence to their own projects.” So starts the preface to this textbook.As one who works part time in research on igneous rocks, especially as they relate to mineral deposits, I have been looking for such a book with this avowed purpose in a field that has a choking richness of evolving terminology and a bewildering volume of interdisciplinary literature. In addition to the standard topics of igneous petrology, the book contains a chapter on the role of igneous activity in the genesis of mineral deposits, its value to geothermal energy, and the potential of igneous rocks as an environment for nuclear waste disposal. These topics are presented rather apologetically in the preface, but the author is to be applauded for including this chapter. The apology shows just how new these interests are to petrology. Recognition is finally coming that, for example, mineral deposits are not “sports of nature,” a view held even by many economic geologists as recently as the early 1960's; instead they are perfectly ordinary geochemical features formed by perfectly ordinary geologic processes. In fact, the mineral deposits and their attendant alteration zones probably have as much to tell us about igneous rocks as the igneous rocks have to tell us about mineral deposits.

  3. Radioactivities (dose rates) of rocks in Japan

    International Nuclear Information System (INIS)

    Matsuda, Hideharu; Minato, Susumu

    1995-01-01

    The radioactive distribution (radiation doses) of major rocks in Japan was monitored to clarify the factors influencing terrestrial gamma-ray absorbed dose rates. The rock samples were reduced to powder and analyzed by well-type NaI(Tl) scintillation detector and pulse height analyzer. Terrestrial gamma-ray dose rates were estimated in terms of gamma radiation dose rate 1 m above the ground. The radioactivity concentration was highest in acidic rock which contains much SiO 2 among igneous rock, followed by neutral rock, basic rock, and ultrabasic rock. The radioactive concentration was 30-40% lower in acidic and clastic rocks than those of the world average concentration. Higher radioactive concentration was observed in soils than the parent rocks of sedimentary rock and metamorphic rock. The gamma radiation dose rate was in proportion to the radioactive concentration of the rocks. To clarify the radioactive effect in the change course of rocks into soils, comparative measurement of outcrop and soil radioactive concentrations is important. (S.Y.)

  4. Rock critics as 'Mouldy Modernists'

    Directory of Open Access Journals (Sweden)

    Becky Shepherd

    2011-08-01

    Full Text Available Contemporary rock criticism appears to be firmly tied to the past. The specialist music press valorise rock music of the 1960s and 1970s, and new emerging artists are championed for their ‘retro’ sounding music by journalists who compare the sound of these new artists with those included in the established ‘canon’ of rock music. This article examines the narrative tropes of authenticity and nostalgia that frame the retrospective focus of this contemporary rock writing, and most significantly, the maintenance of the rock canon within contemporary popular culture. The article concludes by suggesting that while contemporary rock criticism is predominately characterised by nostalgia, this nostalgia is not simply a passive romanticism of the past. Rather, this nostalgia fuels a process of active recontextualisation within contemporary popular culture.

  5. Bioremediation in fractured rock: 2. Mobilization of chloroethene compounds from the rock matrix

    Science.gov (United States)

    Shapiro, Allen M.; Tiedeman, Claire; Imbrigiotta, Thomas; Goode, Daniel J.; Hsieh, Paul A.; Lacombe, Pierre; DeFlaun, Mary F.; Drew, Scott R.; Curtis, Gary P.

    2018-01-01

    A mass balance is formulated to evaluate the mobilization of chlorinated ethene compounds (CE) from the rock matrix of a fractured mudstone aquifer under pre- and postbioremediation conditions. The analysis relies on a sparse number of monitoring locations and is constrained by a detailed description of the groundwater flow regime. Groundwater flow modeling developed under the site characterization identified groundwater fluxes to formulate the CE mass balance in the rock volume exposed to the injected remediation amendments. Differences in the CE fluxes into and out of the rock volume identify the total CE mobilized from diffusion, desorption, and nonaqueous phase liquid dissolution under pre- and postinjection conditions. The initial CE mass in the rock matrix prior to remediation is estimated using analyses of CE in rock core. The CE mass mobilized per year under preinjection conditions is small relative to the total CE mass in the rock, indicating that current pump-and-treat and natural attenuation conditions are likely to require hundreds of years to achieve groundwater concentrations that meet regulatory guidelines. The postinjection CE mobilization rate increased by approximately an order of magnitude over the 5 years of monitoring after the amendment injection. This rate is likely to decrease and additional remediation applications over several decades would still be needed to reduce CE mass in the rock matrix to levels where groundwater concentrations in fractures achieve regulatory standards.

  6. The thin section rock physics: Modeling and measurement of seismic wave velocity on the slice of carbonates

    Energy Technology Data Exchange (ETDEWEB)

    Wardaya, P. D., E-mail: pongga.wardaya@utp.edu.my; Noh, K. A. B. M., E-mail: pongga.wardaya@utp.edu.my; Yusoff, W. I. B. W., E-mail: pongga.wardaya@utp.edu.my [Petroleum Geosciences Department, Universiti Teknologi PETRONAS, Tronoh, Perak, 31750 (Malaysia); Ridha, S. [Petroleum Engineering Department, Universiti Teknologi PETRONAS, Tronoh, Perak, 31750 (Malaysia); Nurhandoko, B. E. B. [Wave Inversion and Subsurface Fluid Imaging Research Laboratory (WISFIR), Dept. of Physics, Institute of Technology Bandung, Bandung, Indonesia and Rock Fluid Imaging Lab, Bandung (Indonesia)

    2014-09-25

    This paper discusses a new approach for investigating the seismic wave velocity of rock, specifically carbonates, as affected by their pore structures. While the conventional routine of seismic velocity measurement highly depends on the extensive laboratory experiment, the proposed approach utilizes the digital rock physics view which lies on the numerical experiment. Thus, instead of using core sample, we use the thin section image of carbonate rock to measure the effective seismic wave velocity when travelling on it. In the numerical experiment, thin section images act as the medium on which wave propagation will be simulated. For the modeling, an advanced technique based on artificial neural network was employed for building the velocity and density profile, replacing image's RGB pixel value with the seismic velocity and density of each rock constituent. Then, ultrasonic wave was simulated to propagate in the thin section image by using finite difference time domain method, based on assumption of an acoustic-isotropic medium. Effective velocities were drawn from the recorded signal and being compared to the velocity modeling from Wyllie time average model and Kuster-Toksoz rock physics model. To perform the modeling, image analysis routines were undertaken for quantifying the pore aspect ratio that is assumed to represent the rocks pore structure. In addition, porosity and mineral fraction required for velocity modeling were also quantified by using integrated neural network and image analysis technique. It was found that the Kuster-Toksoz gives the closer prediction to the measured velocity as compared to the Wyllie time average model. We also conclude that Wyllie time average that does not incorporate the pore structure parameter deviates significantly for samples having more than 40% porosity. Utilizing this approach we found a good agreement between numerical experiment and theoretically derived rock physics model for estimating the effective seismic

  7. The thin section rock physics: Modeling and measurement of seismic wave velocity on the slice of carbonates

    International Nuclear Information System (INIS)

    Wardaya, P. D.; Noh, K. A. B. M.; Yusoff, W. I. B. W.; Ridha, S.; Nurhandoko, B. E. B.

    2014-01-01

    This paper discusses a new approach for investigating the seismic wave velocity of rock, specifically carbonates, as affected by their pore structures. While the conventional routine of seismic velocity measurement highly depends on the extensive laboratory experiment, the proposed approach utilizes the digital rock physics view which lies on the numerical experiment. Thus, instead of using core sample, we use the thin section image of carbonate rock to measure the effective seismic wave velocity when travelling on it. In the numerical experiment, thin section images act as the medium on which wave propagation will be simulated. For the modeling, an advanced technique based on artificial neural network was employed for building the velocity and density profile, replacing image's RGB pixel value with the seismic velocity and density of each rock constituent. Then, ultrasonic wave was simulated to propagate in the thin section image by using finite difference time domain method, based on assumption of an acoustic-isotropic medium. Effective velocities were drawn from the recorded signal and being compared to the velocity modeling from Wyllie time average model and Kuster-Toksoz rock physics model. To perform the modeling, image analysis routines were undertaken for quantifying the pore aspect ratio that is assumed to represent the rocks pore structure. In addition, porosity and mineral fraction required for velocity modeling were also quantified by using integrated neural network and image analysis technique. It was found that the Kuster-Toksoz gives the closer prediction to the measured velocity as compared to the Wyllie time average model. We also conclude that Wyllie time average that does not incorporate the pore structure parameter deviates significantly for samples having more than 40% porosity. Utilizing this approach we found a good agreement between numerical experiment and theoretically derived rock physics model for estimating the effective seismic wave

  8. Scale and size effects in dynamic fracture of concretes and rocks

    Directory of Open Access Journals (Sweden)

    Petrov Y.

    2015-01-01

    Full Text Available Structural-temporal approach based on the notion of incubation time is used for interpretation of strain-rate effects in the fracture process of concretes and rocks. It is established that temporal dependences of concretes and rocks are calculated by the incubation time criterion. Experimentally observed different relations between ultimate stresses of concrete and mortar in static and dynamic conditions are explained. It is obtained that compressive strength of mortar at a low strain rate is greater than that of concrete, but at a high strain rate the opposite is true. Influence of confinement pressure on the mechanism of dynamic strength for concretes and rocks is discussed. Both size effect and scale effect for concrete and rocks samples subjected to impact loading are analyzed. Statistical nature of a size effect contrasts to a scale effect that is related to the definition of a spatio-temporal representative volume determining the fracture event on the given scale level.

  9. Regulation of ROCK Activity in Cancer

    DEFF Research Database (Denmark)

    Morgan-Fisher, Marie; Wewer, Ulla M; Yoneda, Atsuko

    2013-01-01

    , these findings demonstrate additional modes to regulate ROCK activity. This review describes the molecular mechanisms of ROCK activity regulation in cancer, with emphasis on ROCK isoform-specific regulation and interaction partners, and discusses the potential of ROCKs as therapeutic targets in cancer.......Cancer-associated changes in cellular behavior, such as modified cell-cell contact, increased migratory potential, and generation of cellular force, all require alteration of the cytoskeleton. Two homologous mammalian serine/threonine kinases, Rho-associated protein kinases (ROCK I and II), are key...... regulators of the actin cytoskeleton acting downstream of the small GTPase Rho. ROCK is associated with cancer progression, and ROCK protein expression is elevated in several types of cancer. ROCKs exist in a closed, inactive conformation under quiescent conditions, which is changed to an open, active...

  10. Evaluating and quantifying the liming potential of phosphate rocks

    International Nuclear Information System (INIS)

    Sikora, F.J.

    2002-01-01

    The liming potential of phosphate rock was evaluated with theoretical calculations and quantified by laboratory titration and soil incubation. Three anions present in the carbonate apatite structure of phosphate rock that can consume protons and cause an increase in pH when dissolved from apatite are PO 4 3- , CO 3 2- , and F - . The pKa for HF is so low that F - has very little effect on increasing pH. The pKa for 2 protons on H 2 PO 4 - and H 2 CO 3 are sufficiently high enough to cause an increase in pH with PO 4 3- and CO 3 2- released into solution if the pH range is between 4 and 6. Because of the greater molar quantity of PO 4 3- compared toCO 3 2- , PO 4 3- exerts a greater affect on the liming potential of P rock. For a variety of phosphate rocks with a axes ranging from 9.322 to 9.374 A in the carbonate apatite structure, the theoretical % calcium carbonate equivalence (CCE) ranges from 59.5 to 62%. With the presence of gangue carbonate minerals from 2.5 to 10% on a weight basis in the phosphate rocks, the theoretical %CCE ranges from 59.5 to 63.1%. Use of AOAC method 955.01 for quantifying the %CCE of North Carolina phosphate rock (NCPR) and Idaho phosphate rock (IDPR) resulted in %CCE ranging from 39.9 to 53.7% which were less than the theoretical values. The lower values measured in the AOAC method was presumed to be due to formation of CaHPO 4 or CaHPO 4 ·2H 2 O precipitates which would result in less than 2 protons neutralized per mole of PO 4 3- released from carbonate apatite. The highly concentrated solution formed in the method was considered not indicative of a soil solution and thus determined %CCE values would be suspect. A soil incubation study was conducted to determine a more appropriate %CCE value in a soil environment using Copper Basin, Tennessee soil with a soil pH of 4.2. Agricultural limestone, NCPR, IDPR, and a granulated IDPR were added to 100 g of soil at rates of 0.1, 0.3, 1, 3, and 10 g/kg soil, incubated for 105 days at field

  11. Structural characterization of the rock mass of the underground mine Oro Descanso

    Directory of Open Access Journals (Sweden)

    Adeoluwa Olajesu Oluwaseyi

    2017-10-01

    Full Text Available In the rocky massif where the Oro Descanso underground mine is located, an assessment was made of the physical-mechanical properties of rocks, cracking and blocking, in order to propose safe tillage measures for underground mining excavations using appropriate empirical methods. From the evaluation made it was concluded that the massif is composed of areas of rocks of different quality: good, fair and poor. It is proposed for the area of good quality to work excavations with complete advance, of free length 1.0-1.5 m, using in the crown the support of cemented anchors of diameter 20 mm, length 3 m and spaced 2.5 m and apply concrete released 50 mm thick. For the zone of bad and regular quality, it is suggested to work in stepwise progression, of free length of 1-3 m and after each blasting, to install in the crown, cemented anchors of diameter 20 mm, length 4-5 m and spacing 1-2 m, placing on the sides metallic mesh, with concrete cast 50-150 mm thick.

  12. Structural and neural network analyses of fracture systems at the Aespoe Hard Rock Laboratory, SE Sweden

    International Nuclear Information System (INIS)

    Sirat, M.

    1999-01-01

    The > 10,000 fractures documented in the 450 m deep Aespoe Hard Rock Laboratory (HRL) provide a unique opportunity to study brittle deformation of a Swedish bedrock mass. The fracture population consists of six major sets, one sub-horizontal and five sub-vertical. A classical structural analysis explored the interrelations between geometry and frequency of both dry and wet fractures with respect to depth and in-situ stresses. Three main findings are: In-situ stresses govern frequency distributions of dilated, hence water-bearing fractures. About 68.5% of sub-horizontal fractures are dilated in the thrust regime above a depth of ca. 230 m while 53% of sub-vertical fractures are dilated in the underlying wrench regime. Fractures curve both horizontally and vertically, a finding confirmed by the application of artificial neural networks that included Back-Propagation and Self-Organizing (Kohonen) networks. The asymmetry of the total fracture population and tilts of the sub-Cambrian peneplain demonstrates that multiple reactivations of fractures have tilted the Aespoe rock mass 6 deg to the west. The potential space problem raised by this tilt is negated by systematic curvature of steep fractures, some of which sole out to gently dipping fracture zones. Fractures probably developed their curvature when they formed deep in crystalline crust in Precambrian times but have since reactivated at shallow depths. These findings add significantly to the conceptual model of Aespoe and should be taken into account in future studies regarding the isolation of Sweden's high-grade radioactive waste in crystalline bedrock

  13. ROCK1-directed basement membrane positioning coordinates epithelial tissue polarity.

    Science.gov (United States)

    Daley, William P; Gervais, Elise M; Centanni, Samuel W; Gulfo, Kathryn M; Nelson, Deirdre A; Larsen, Melinda

    2012-01-01

    The basement membrane is crucial for epithelial tissue organization and function. However, the mechanisms by which basement membrane is restricted to the basal periphery of epithelial tissues and the basement membrane-mediated signals that regulate coordinated tissue organization are not well defined. Here, we report that Rho kinase (ROCK) controls coordinated tissue organization by restricting basement membrane to the epithelial basal periphery in developing mouse submandibular salivary glands, and that ROCK inhibition results in accumulation of ectopic basement membrane throughout the epithelial compartment. ROCK-regulated restriction of PAR-1b (MARK2) localization in the outer basal epithelial cell layer is required for basement membrane positioning at the tissue periphery. PAR-1b is specifically required for basement membrane deposition, as inhibition of PAR-1b kinase activity prevents basement membrane deposition and disrupts overall tissue organization, and suppression of PAR-1b together with ROCK inhibition prevents interior accumulations of basement membrane. Conversely, ectopic overexpression of wild-type PAR-1b results in ectopic interior basement membrane deposition. Significantly, culture of salivary epithelial cells on exogenous basement membrane rescues epithelial organization in the presence of ROCK1 or PAR-1b inhibition, and this basement membrane-mediated rescue requires functional integrin β1 to maintain epithelial cell-cell adhesions. Taken together, these studies indicate that ROCK1/PAR-1b-dependent regulation of basement membrane placement is required for the coordination of tissue polarity and the elaboration of tissue structure in the developing submandibular salivary gland.

  14. 2008 Gordon Research Conference on Rock Deformation

    Energy Technology Data Exchange (ETDEWEB)

    Hirth, James G.; Gray, Nancy Ryan

    2009-09-21

    The GRC on Rock Deformation highlights the latest research in brittle and ductile rock mechanics from experimental, field and theoretical perspectives. The conference promotes a multi-disciplinary forum for assessing our understanding of rock strength and related physical properties in the Earth. The theme for the 2008 conference is 'Real-time Rheology'. Using ever-improving geophysical techniques, our ability to constrain the rheological behavior during earthquakes and post-seismic creep has improved significantly. Such data are used to investigate the frictional behavior of faults, processes responsible for strain localization, the viscosity of the lower crust, and viscous coupling between the crust and mantle. Seismological data also provide information on the rheology of the lower crust and mantle through analysis of seismic attenuation and anisotropy. Geologists are improving our understanding of rheology by combining novel analyses of microstructures in naturally deformed rocks with petrologic data. This conference will bring together experts and students in these research areas with experimentalists and theoreticians studying the same processes. We will discuss and assess where agreement exists on rheological constraints derived at different length/time scales using different techniques - and where new insight is required. To encompass the elements of these topics, speakers and discussion leaders with backgrounds in geodesy, experimental rock deformation, structural geology, earthquake seismology, geodynamics, glaciology, materials science, and mineral physics will be invited to the conference. Thematic sessions will be organized on the dynamics of earthquake rupture, the rheology of the lower crust and coupling with the upper mantle, the measurement and interpretation of seismic attenuation and anisotropy, the dynamics of ice sheets and the coupling of reactive porous flow and brittle deformation for understanding geothermal and chemical

  15. Free-face-Assisted Rock Breaking Method Based on the Multi-stage Tunnel Boring Machine (TBM) Cutterhead

    Science.gov (United States)

    Geng, Qi; Wei, Zhengying; Meng, Hao; Macias, Francisco Javier; Bruland, Amund

    2016-11-01

    In order to improve the rock breaking efficiency of hard rock tunnel boring, many innovative rock breaking methods have been proposed (e.g., the water jet cutting, the high-power laser cutting, the impact-rotary drilling, and the undercutting method). However, most of the methods are not applicable to TBMs due to some structural reasons. Aiming on this problem, a free-face-assisted rock breaking method based on the multi-stage TBM cutterhead has been proposed. Series of proof-of-concept tests includes (1) the static compression test with vertical free face and (2) the rotary cutting tests in different free surface conditions were designed and carried out. The results show that the rock breaking force and efficiency can be significantly reduced and improved, respectively, with the assistance of the free face, due to the failure of the rock close to the free face is tensile-dominated failure. The influencing distance of the free face in the radial direction is at least 330 mm which covers about 5 disk cutters. Finally, the general structure of a small two-stage cutterhead (4 m in diameter) was tentatively designed in order to provide a possible approach to apply the free-face effect to TBMs.

  16. Analytical solutions for recession analyses of sloping aquifers - applicability on relict rock glaciers in alpine catchments

    Science.gov (United States)

    Pauritsch, Marcus; Birk, Steffen; Hergarten, Stefan; Kellerer-Pirklbauer, Andreas; Winkler, Gerfried

    2014-05-01

    Rock glaciers as aquifer systems in alpine catchments may strongly influence the hydrological characteristics of these catchments. Thus, they have a high impact on the ecosystem and potential natural hazards such as for example debris flow. Therefore, knowledge of the hydrodynamic processes, internal structure and properties of these aquifers is important for resource management and risk assessment. The investigation of such aquifers often turns out to be expensive and technically complicated because of their strongly limited accessibility. Analytical solutions of discharge recession provide a quick and easy way to estimate aquifer parameters. However, due to simplifying assumptions the validity of the interpretation is often questionable. In this study we compared results of an analytical solution of discharge recessions with results based on a numerical model. This was done in order to analyse the range of uncertainties and the applicability of the analytical method in alpine catchment areas. The research area is a 0.76 km² large catchment in the Seckauer Tauern Range, Austria. The dominant aquifer in this catchment is a rock glacier, namely the Schöneben Rock Glacier. This relict rock glacier (i.e. containing no permafrost at present) covers an area of 0.11 km² and is drained by one spring at the rock glacier front. The rock glacier consists predominantly of gneissic sediments (mainly coarse-grained, blocky at the surface) and extends from 1720 to 1905 m a.s.l.. Discharge of the rock glacier spring is automatically measured since 2002. Electric conductivity and water temperature is monitored since 2008. An automatic weather station was installed in 2011 in the central part of the catchment. Additionally data of geophysical surveys (refraction seismic and ground penetrating radar) have been used to analyse the base slope and inner structure of the rock glacier. The measured data are incorporated into a numerical model implemented in MODFLOW. The numerical

  17. A computer-assisted rock type data catalogue for gas formations; Ein rechnergestuetzter Gesteinsdatenkatalog fuer Gasformationen

    Energy Technology Data Exchange (ETDEWEB)

    Reitenbach, V.; Pusch, G.; Moeller, M.; Koll, S. [TU Clausthal (Germany). Inst. fuer Erdoel- und Erdgastechnik; Constantini, A.; Junker, A.; Anton, H. [RWE Dea AG, Hamburg (Germany)

    2007-09-13

    Modern reservoir management commonly requires versatile reservoir data which are neces-sary for integrated reservoir characterization, evaluation and development planning. The rock data necessary for numerical reservoir simulation studies often have to be collected from different sources, analysed and sorted with a considerable effort. In a framework of DGMK research program (DGMK project 593-9/4), the Institute of Petro-leum Engineering (Clausthal University of Technology) and RWE DEA AG have developed a new tool named Rock Data Catalogue, which is capable of managing large amounts of rock data more efficiently and deriving new specific correlations for European rock types. The use of Rock Data Catalogue can facilitate the essential input data generation and proc-essing procedure for reservoir simulation studies. The Rock Data Catalogue is comprised of a Data Base Module of digitalized reservoir rock data and an interactive Data Correlation Module. Both modules are built-up as an interface to common reservoir simulation software. The universal structure of the software also makes it possible to exchange the data with other rock data information systems. The Data Correlation Module implements a ''Decision-Structure'' module, which helps the reservoir engineer to select the rock data for analysis and correlation depending on its litho-facial type and permeability class. The Data Base Module enables a quick search of appro-priated data sets and their export into the correlation module. The open source data of the North German Rotliegend gas formations as well as the data of measurements on Rotliegend core samples performed at the ITE in course of the DGMK tight gas projects were implemented in the rock data base. Correlations of poro/perm data, two-phase flow and capillary pressure functions of the Rotliegend sandstones with the per-meability range between 20 and 0.01 mD are implemented in the rock data base and serve for quality checking of the

  18. Rock in Rio: forever young

    Directory of Open Access Journals (Sweden)

    Ricardo Ferreira Freitas

    2014-12-01

    Full Text Available The purpose of this article is to discuss the role of Rock in Rio: The Musical, as herald of megafestival Rock in Rio. Driven by the success that musicals have reached in Brazil, we believe that the design of this spectacle of music, dance and staging renews the brand of the rock festival, once it adds the force of young and healthy bodies to its concept. Moreover, the musical provides Rock in Rio with some distance from the controversal trilogy of sex, drugs and rock and roll, a strong mark of past festivals around the world. Thus, the musical expands the possibilities of growth for the brand.

  19. Biological energy from the igneous rock enhances cell growth and enzyme activity

    International Nuclear Information System (INIS)

    Lin Y.-L.; Kuo, H.-S; Chen, C.-T.; Kuo, S.-C.

    2000-01-01

    Some effects from natural resources might be ignored and unused by humans. Environmental hormesis could be a phenomena necessary to bio-organism existence on earth. Since 1919, radiation and some heavy metal hormesis from the environment were proved in various reports. In this study, igneous rock with very low radioactivity and high ferrous activity was measured by multichannel analyzer and inductively coupled plasma analyzer. The water treated by igneous rock, both directly soaked or indirectly in contact, induced increased activities of glucose oxidase, catalase, peroxidase, and superoxide dismutase. It also increased cell growth of SC-M1, HCT-15, Raji, and fibroblast cell lines. The water after treatment of igneous rock had no change in pH values, but displayed decreased conductivity values. We assume that the igneous rock could transfer energy to water to change the molecular structure or conformation of water cluster, or by radiation hormesis effect could then induce increased enzyme activity and cell growth. It is also possible that the energy from rock may combine radiation hormesis with other transferable biological energy forms to change water cluster conformation

  20. Study on evaluation method for heterogeneous sedimentary rocks based on forward model

    International Nuclear Information System (INIS)

    Masui, Yasuhiro; Kawada, Koji; Katoh, Arata; Tsuji, Takashi; Suwabe, Mizue

    2004-02-01

    It is very important to estimate the facies distribution of heterogeneous sedimentary rocks for geological disposal of high level radioactive waste. The heterogeneousness of sedimentary rocks is due to variable distribution of grain size and mineral composition. The objective of this study is to establish the evaluation method for heterogeneous sedimentary rocks based on forward model. This study consisted of geological study for Horonobe area and the development of soft wear for sedimentary model. Geological study was composed of following items. 1. The sedimentary system for Koetoi and Wakkanai formations in Horonobe area was compiled based on papers. 2. The cores of HDB-1 were observed mainly from sedimentological view. 3. The facies and compaction property of argillaceous rocks were studied based on physical logs and core analysis data of wells. 4. The structure maps, isochrone maps, isopach maps and restored geological sections were made. The soft wear for sedimentary model to show sedimentary system on a basin scale was developed. This soft wear estimates the facies distribution and hydraulic conductivity of sedimentary rocks on three dimensions scale by numerical simulation. (author)

  1. Hydrogeomechanics for rock engineering: coupling subsurface hydrogeomechanical assessement and hydrogeotechnical mapping on fracturated rock masses

    OpenAIRE

    Meirinhos, João Miguel de Freitas

    2015-01-01

    The present work aims to achieve and further develop a hydrogeomechanical approach in Caldas da Cavaca hydromineral system rock mass (Aguiar da Beira, NW Portugal), and contribute to a better understanding of the hydrogeological conceptual site model. A collection of several data, namely geology, hydrogeology, rock and soil geotechnics, borehole hydraulics and hydrogeomechanics, was retrieved from three rock slopes (Lagoa, Amores and Cancela). To accomplish a comprehensive analysis and rock e...

  2. The Stability of Metasedimentary Rock in Ranau, Sabah, Malaysia

    Directory of Open Access Journals (Sweden)

    Ismail Abd Rahim

    2018-01-01

    Full Text Available DOI: 10.17014/ijog.5.1.23-31The aim of this paper is to determine the stability of slopes and to propose preliminary rock cut slope protection and stabilization measures for Paleocene to Middle Eocene Trusmadi Formation along Marakau-Kigiok in Ranau, Sabah, Malaysia. The rock of Trusmadi Formation is slightly metamorphosed and dominated by interbeds of sandstone with quartz vein (metagreywacke, metamudstone, shale, slate, sheared sandstone, and mudstone. The rock unit can be divided into four geotechnical units namely arenaceous unit, argillaceous unit, interbedded unit, and sheared unit. Twelve slopes were selected for this study. Geological mapping, discontinuity survey, kinematic analysis, and prescriptive measure were used in this study. Results of this study conclude that the potential modes of failures are planar and wedge. Terrace, surface drainage, weep holes, horizontal drain, vegetation cover, wire mesh, slope reprofiling, and retaining structure were proposed protection and stabilization measures for the slopes in the studied area.

  3. Analysis of rock stress and rock stress measurements with application to Aespoe HRL

    International Nuclear Information System (INIS)

    Lundholm, Beatrice

    2000-11-01

    The process of choosing a site for a nuclear waste repository means that many aspects have to be taken into consideration. One of these is that the repository has to be mechanically stable for a long time. The mechanical stability of the rock is very difficult to determine. One of several factors, which determine the mechanical stability, is the virgin state of stress. The thesis project consists of two parts. In the first part the state of stress at Aespoe Hard Rock Laboratory had to be defined. This was done based on earlier rock stress measurements conducted during the years 1988 to 1997. Two different measurement techniques have been used, hydraulic fracturing and overcoring. During the overcoring two types of cells have been used, CSIRO HI-cell and a cell developed by the Swedish State Power Board (SSPB). In the second part of the project, investigation of the correlation between the stress and geological structures are made using numerical modelling tools such as FLAC, UDEC and 3DEC. The rock stress measurements using the hydraulic fracturing gave orientations of the horizontal stress that coincide with earlier hydraulic fracturing measurements conducted in Scandinavia. The magnitudes of rock stresses are slightly lower than the earlier reported stress magnitudes for the Scandinavian part of the earth crust. The rock stresses obtained from the overcoring resulted in higher stresses than what was predicted by the hydraulic fracturing measurements. However, the orientation of the maximum horizontal stresses coincides well between the two techniques. The orientation is also more or less constant with respect to increasing depth. The state of stress at Aespoe is defined by using the results from the hydraulic fracturing and the measurements conducted by SSPB-cell. The measurements from the SSPB-cell are used since these have a Poisson's ratio that corresponds well with the uniaxial tests of rock samples and since the measurements have been done at a distance from

  4. Seismic evidence for multiple-stage exhumation of high/ultrahigh pressure metamorphic rocks in the eastern Dabie orogenic belt

    Science.gov (United States)

    Luo, Yinhe; Zhao, Kaifeng; Tang, Chi-Chia; Xu, Yixian

    2018-05-01

    The Dabie-Sulu orogenic belt in China contains one of the largest exposures of high and ultrahigh pressure (HP and UHP) metamorphic rocks in the world. The origin of HP/UHP metamorphic rocks and their exhumation to the surface in this belt have attracted great interest in the geologic community because the study of exhumation history of HP/UHP rocks helps to understand the process of continental-continental collision and the tectonic evolution of post-collision. However, the exhumation mechanism of the HP-UHP rocks to the surface is still contentious. In this study, by deploying 28 broadband seismic stations in the eastern Dabie orogenic belt and combining seismic data from 40 stations of the China National Seismic Network (CNSN), we image the high-resolution crustal isotropic shear velocity and radial anisotropy structure using ambient noise tomography. Our high-resolution 3D models provide new information about the exhumation mechanism of HP/UHP rocks and the origin of two dome structures.

  5. Underground Research Laboratories for Crystalline Rock and Sedimentary Rock in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Shigeta, N.; Takeda, S.; Matsui, H.; Yamasaki, S.

    2003-02-27

    The Japan Nuclear Cycle Development Institute (JNC) has started two off-site (generic) underground research laboratory (URL) projects, one for crystalline rock as a fractured media and the other for sedimentary rock as a porous media. This paper introduces an overview and current status of these projects.

  6. Regulation of ROCK Activity in Cancer

    Science.gov (United States)

    Morgan-Fisher, Marie; Wewer, Ulla M.

    2013-01-01

    Cancer-associated changes in cellular behavior, such as modified cell-cell contact, increased migratory potential, and generation of cellular force, all require alteration of the cytoskeleton. Two homologous mammalian serine/threonine kinases, Rho-associated protein kinases (ROCK I and II), are key regulators of the actin cytoskeleton acting downstream of the small GTPase Rho. ROCK is associated with cancer progression, and ROCK protein expression is elevated in several types of cancer. ROCKs exist in a closed, inactive conformation under quiescent conditions, which is changed to an open, active conformation by the direct binding of guanosine triphosphate (GTP)–loaded Rho. In recent years, a number of ROCK isoform-specific binding partners have been found to modulate the kinase activity through direct interactions with the catalytic domain or via altered cellular localization of the kinases. Thus, these findings demonstrate additional modes to regulate ROCK activity. This review describes the molecular mechanisms of ROCK activity regulation in cancer, with emphasis on ROCK isoform-specific regulation and interaction partners, and discusses the potential of ROCKs as therapeutic targets in cancer. PMID:23204112

  7. Bioremediation in Fractured Rock: 2. Mobilization of Chloroethene Compounds from the Rock Matrix.

    Science.gov (United States)

    Shapiro, Allen M; Tiedeman, Claire R; Imbrigiotta, Thomas E; Goode, Daniel J; Hsieh, Paul A; Lacombe, Pierre J; DeFlaun, Mary F; Drew, Scott R; Curtis, Gary P

    2018-03-01

    A mass balance is formulated to evaluate the mobilization of chlorinated ethene compounds (CE) from the rock matrix of a fractured mudstone aquifer under pre- and postbioremediation conditions. The analysis relies on a sparse number of monitoring locations and is constrained by a detailed description of the groundwater flow regime. Groundwater flow modeling developed under the site characterization identified groundwater fluxes to formulate the CE mass balance in the rock volume exposed to the injected remediation amendments. Differences in the CE fluxes into and out of the rock volume identify the total CE mobilized from diffusion, desorption, and nonaqueous phase liquid dissolution under pre- and postinjection conditions. The initial CE mass in the rock matrix prior to remediation is estimated using analyses of CE in rock core. The CE mass mobilized per year under preinjection conditions is small relative to the total CE mass in the rock, indicating that current pump-and-treat and natural attenuation conditions are likely to require hundreds of years to achieve groundwater concentrations that meet regulatory guidelines. The postinjection CE mobilization rate increased by approximately an order of magnitude over the 5 years of monitoring after the amendment injection. This rate is likely to decrease and additional remediation applications over several decades would still be needed to reduce CE mass in the rock matrix to levels where groundwater concentrations in fractures achieve regulatory standards. © 2017, National Ground Water Association.

  8. Extracting real-crack properties from non-linear elastic behaviour of rocks: abundance of cracks with dominating normal compliance and rocks with negative Poisson ratios

    Directory of Open Access Journals (Sweden)

    V. Y. Zaitsev

    2017-09-01

    Full Text Available Results of examination of experimental data on non-linear elasticity of rocks using experimentally determined pressure dependences of P- and S-wave velocities from various literature sources are presented. Overall, over 90 rock samples are considered. Interpretation of the data is performed using an effective-medium description in which cracks are considered as compliant defects with explicitly introduced shear and normal compliances without specifying a particular crack model with an a priori given ratio of the compliances. Comparison with the experimental data indicated abundance (∼ 80 % of cracks with the normal-to-shear compliance ratios that significantly exceed the values typical of conventionally used crack models (such as penny-shaped cuts or thin ellipsoidal cracks. Correspondingly, rocks with such cracks demonstrate a strongly decreased Poisson ratio including a significant (∼ 45 % portion of rocks exhibiting negative Poisson ratios at lower pressures, for which the concentration of not yet closed cracks is maximal. The obtained results indicate the necessity for further development of crack models to account for the revealed numerous examples of cracks with strong domination of normal compliance. Discovering such a significant number of naturally auxetic rocks is in contrast to the conventional viewpoint that occurrence of a negative Poisson ratio is an exotic fact that is mostly discussed for artificial structures.

  9. Loading History Effect on Creep Deformation of Rock

    Directory of Open Access Journals (Sweden)

    Wendong Yang

    2018-06-01

    Full Text Available The creep characteristics of rocks are very important for assessing the long-term stability of rock engineering structures. Two loading methods are commonly used in creep tests: single-step loading and multi-step loading. The multi-step loading method avoids the discrete influence of rock specimens on creep deformation and is relatively time-efficient. It has been widely accepted by researchers in the area of creep testing. However, in the process of multi-step loading, later deformation is affected by earlier loading. This is a key problem in considering the effects of loading history. Therefore, we intend to analyze the deformation laws of rock under multi-step loading and propose a method to correct the disturbance of the preceding load. Based on multi-step loading creep tests, the memory effect of creep deformation caused by loading history is discussed in this paper. A time-affected correction method for the creep strains under multi-step loading is proposed. From this correction method, the creep deformation under single-step loading can be estimated by the super-position of creeps obtained by the dissolution of a multistep creep. We compare the time-affected correction method to the coordinate translation method without considering loading history. The results show that the former results are more consistent with the experimental results. The coordinate translation method produces a large error which should be avoided.

  10. A review of numerical techniques approaching microstructures of crystalline rocks

    Science.gov (United States)

    Zhang, Yahui; Wong, Louis Ngai Yuen

    2018-06-01

    The macro-mechanical behavior of crystalline rocks including strength, deformability and failure pattern are dominantly influenced by their grain-scale structures. Numerical technique is commonly used to assist understanding the complicated mechanisms from a microscopic perspective. Each numerical method has its respective strengths and limitations. This review paper elucidates how numerical techniques take geometrical aspects of the grain into consideration. Four categories of numerical methods are examined: particle-based methods, block-based methods, grain-based methods, and node-based methods. Focusing on the grain-scale characters, specific relevant issues including increasing complexity of micro-structure, deformation and breakage of model elements, fracturing and fragmentation process are described in more detail. Therefore, the intrinsic capabilities and limitations of different numerical approaches in terms of accounting for the micro-mechanics of crystalline rocks and their phenomenal mechanical behavior are explicitly presented.

  11. Eos Chaos Rocks

    Science.gov (United States)

    2006-01-01

    11 January 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned, layered rock outcrops in Eos Chaos, located near the east end of the Valles Marineris trough system. The outcrops occur in the form of a distinct, circular butte (upper half of image) and a high slope (lower half of image). The rocks might be sedimentary rocks, similar to those found elsewhere exposed in the Valles Marineris system and the chaotic terrain to the east of the region. Location near: 12.9oS, 49.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

  12. Modeling the Rock Glacier Cycle

    Science.gov (United States)

    Anderson, R. S.; Anderson, L. S.

    2016-12-01

    Rock glaciers are common in many mountain ranges in which the ELA lies above the peaks. They represent some of the most identifiable components of today's cryosphere in these settings. Their oversteepened snouts pose often-overlooked hazards to travel in alpine terrain. Rock glaciers are supported by avalanches and by rockfall from steep headwalls. The winter's avalanche cone must be sufficiently thick not to melt entirely in the summer. The spatial distribution of rock glaciers reflects this dependence on avalanche sources; they are most common on lee sides of ridges where wind-blown snow augments the avalanche source. In the absence of rockfall, this would support a short, cirque glacier. Depending on the relationship between rockfall and avalanche patterns, "talus-derived" and "glacier-derived" rock glaciers are possible. Talus-derived: If the spatial distribution of rock delivery is similar to the avalanche pattern, the rock-ice mixture will travel an englacial path that is downward through the short accumulation zone before turning upward in the ablation zone. Advected debris is then delivered to the base of a growing surface debris layer that reduces the ice melt rate. The physics is identical to the debris-covered glacier case. Glacier-derived: If on the other hand rockfall from the headwall rolls beyond the avalanche cone, it is added directly to the ablation zone of the glacier. The avalanche accumulation zone then supports a pure ice core to the rock glacier. We have developed numerical models designed to capture the full range of glacier to debris-covered glacier to rock glacier behavior. The hundreds of meter lengths, tens of meters thicknesses, and meter per year speeds of rock glaciers are well described by the models. The model can capture both "talus-derived" and "glacier-derived" rock glaciers. We explore the dependence of glacier behavior on climate histories. As climate warms, a pure ice debris-covered glacier can transform to a much shorter rock

  13. Assessment of the rock burst potential in basalt at the Hanford Site

    International Nuclear Information System (INIS)

    Blake, W.

    1984-01-01

    The phenomenon of rock bursting has been reviewed and specific case histories have been presented, along with the measures most commonly taken to minimize their occurrence and effects. A combination of high stresses and brittle rock types is necessary to initiate bursting but is not sufficient to do so unless other parameters are present (i.e. an extensive mined-out area, a high extraction ratio, and geologic structures, or discontinuities). Since none of these parameters will result from the construction of a deep underground nuclear waste repository in basalt at the Hanford Site in Southeastern Washington, rock bursting should not occur either during or after this construction. 75 refs., 35 figs., 2 tabs

  14. Neutron pole figures compared with magnetic preferred orientations of different rock types

    International Nuclear Information System (INIS)

    Hansen, Anke; Chadima, Martin; Cifelli, Francesca; Brokmeier, H.-G.Heinz-Guenter; Siemes, Heinrich

    2004-01-01

    Neutron diffraction is an excellent tool for pole figure measurement of rock samples. Due to high penetration depth of neutrons for most materials neutron diffraction represents an efficient tool to measure complete pole figures with reliable grain statistics even in coarse grained or inequi-granular materials. In the field of structural geology, the measurement of anisotropy of magnetic susceptibility is a standard technique to reveal the tectonic history of deformed rocks. The application of both techniques on still ongoing studies of Precambrian, Carboniferous and Quaternary rocks which are characterised by fundamental different tectonic evolutions and mineralogical compositions shows the wide field of relevance and importance of these methods in understanding tectonic processes in detail

  15. In silico prediction of ROCK II inhibitors by different classification approaches.

    Science.gov (United States)

    Cai, Chuipu; Wu, Qihui; Luo, Yunxia; Ma, Huili; Shen, Jiangang; Zhang, Yongbin; Yang, Lei; Chen, Yunbo; Wen, Zehuai; Wang, Qi

    2017-11-01

    ROCK II is an important pharmacological target linked to central nervous system disorders such as Alzheimer's disease. The purpose of this research is to generate ROCK II inhibitor prediction models by machine learning approaches. Firstly, four sets of descriptors were calculated with MOE 2010 and PaDEL-Descriptor, and optimized by F-score and linear forward selection methods. In addition, four classification algorithms were used to initially build 16 classifiers with k-nearest neighbors [Formula: see text], naïve Bayes, Random forest, and support vector machine. Furthermore, three sets of structural fingerprint descriptors were introduced to enhance the predictive capacity of classifiers, which were assessed with fivefold cross-validation, test set validation and external test set validation. The best two models, MFK + MACCS and MLR + SubFP, have both MCC values of 0.925 for external test set. After that, a privileged substructure analysis was performed to reveal common chemical features of ROCK II inhibitors. Finally, binding modes were analyzed to identify relationships between molecular descriptors and activity, while main interactions were revealed by comparing the docking interaction of the most potent and the weakest ROCK II inhibitors. To the best of our knowledge, this is the first report on ROCK II inhibitors utilizing machine learning approaches that provides a new method for discovering novel ROCK II inhibitors.

  16. Critical issues in soft rocks

    OpenAIRE

    Milton Assis Kanji

    2014-01-01

    This paper discusses several efforts made to study and investigate soft rocks, as well as their physico-mechanical characteristics recognized up to now, the problems in their sampling and testing, and the possibility of its reproduction through artificially made soft rocks. The problems in utilizing current and widespread classification systems to some types of weak rocks are also discussed, as well as other problems related to them. Some examples of engineering works in soft rock or in soft ...

  17. Subsurface Geology of the Fenton Hill Hot Dry Rock Geothermal Energy Site

    Energy Technology Data Exchange (ETDEWEB)

    Levey, Schon S.

    2010-12-01

    The Precambrian rock penetrated by wells EE-2A and -3A belongs to one or more granitic to granodioritic plutons. The plutonic rock contains two major xenolith zones of amphibolite, locally surrounded by fine-grained mafic rock of hybrid igneous origin. The granodiorite is cut by numerous leucogranite dikes that diminish in abundance with depth. The most prominent structural feature is the main breccia zone, in which the rock is highly fractured and moderately altered. This zone is at least 75 m thick and is of uncertain but near-horizontal orientation. Fracture abundance decreases with increasing depth below the main breccia zone, and fractures tend to be associated with leucogranite dikes. This association suggests that at least some of the fractures making up the geothermal reservoir are of Precambrian age or have long-range orientations controlled by the presence of Precambrian-age granitic dikes.

  18. Attempt of groundwater dating using the drilled rock core. 1. Development of the rock sampling method for measurement of noble gases dissolved in interstitial water in rock

    International Nuclear Information System (INIS)

    Mahara, Yasunori

    2002-01-01

    Groundwater dating in low permeable rock is very difficult and impracticable, because we take a very long time to collect groundwater sample in a borehole and have to invest much fund in production of the in-situ groundwater sampler and in operation of it. If we can directly measure noble gases dissolved in interstitial groundwater in rock core, we have a big merit to estimate groundwater resident time easy. In this study, we designed and produced a high vacuum container to let dissolved noble gases diffuse until reaching in equilibrium, and we made a handling manual of the rock core into the container and a procedure to vacuum out air from the sealed container. We compared data sets of noble gas concentration obtained from rock cores and groundwater sample collected from boreholes in-situ. The measured rocks are pumice-tuff rock, mud rock and hornfels, which have their permeabilities of 10 -6 cm/s, 10 -9 cm/s and 10 -11 cm/s, respectively. Consequently, we evaluated the rock core method is better than the in-situ groundwater sampling method for low permeable rock. (author)

  19. Current status of crushed rock and whole rock column studies

    International Nuclear Information System (INIS)

    Vine, E.N.; Daniels, W.R.; Rundberg, R.S.; Thompson, J.L.

    1980-01-01

    Measurements on a large number of crushed rock columns of tuff, granite, and argillite are discussed. The isotopes 85 Sr, 137 Cs, 133 Ba, 141 Ce, 152 Eu, /sup 95m/Tc, and 233 U were used. Flow rates were varied from approx. 30 to approx. 30000 m/y. Other parameters studied include isotope concentration and atmosphere. The sorption ratios calculated were compared with batch sorption ratios on the same samples. Methods of studying the movement of radionuclides through whole rock cores are described. The problems associated with sealing the cores to prevent leaking along the exterior surface and one possible solution are discussed. The strontium sorption ratio obtained by elution of one solid tuff core is compared with the batch and crushed rock column sorption ratios

  20. Assessment of rock mass quality based on rock quality designation and rock block index. Taking the Borehole BS01 in Beishan HLW disposal repository as example

    International Nuclear Information System (INIS)

    Xu Jian; Wang Ju

    2006-01-01

    Rock mass quality assessment plays an important role in the security for all kinds of large-scale buildings, especially for the underground buildings. In this paper, based on two parameters of RQD and RBI, taking the Borehole BS01 as example, lots of measured data prove that the rock block index can reflect the integrity and corresponding variation of mechanical properties of core from Borehole BS01 to some extent. Meanwhile, the rock mass classification around the Borehole BS01 is given in this paper. Finally, comparison of the results for rock mass assessment between RBI and RQD is made. The research result shows that the rock block index has remarkable significance in engineering and advantages in rock mass quality assessment. (authors)

  1. Dynamic deformation and failure characteristic of rock foundation by means of effect of cyclic shear loading

    International Nuclear Information System (INIS)

    Fujiwara, Yoshikazu; Hibino, Satoshi; Kanagawa, Tadashi; Komada, Hiroya; Nakagawa, Kameichiro

    1984-01-01

    The main structures of nuclear power plants are built on hard and soft rocks. The rock-dynamic properties used for investigating the stability of the structures have been determined so far by laboratory tests for soft rocks. In hard rocks, however, joints and cracks exist, and the test including these effects is not able to be performed in laboratories at present. Therefore, a dynamic repeating shearing test equipment to be used under the condition including the joints and cracks of actual ground has been made for a base rock of tuff breccia. In this paper, the test results are reported as follows. The geological features of the testing site and the arrangement of tested rocks, the preparation for tests, test equipment, loading method, measuring method, analysis, and the result and the examination. The results of dynamic deformation and failure characteristics were as follows: (1) the dynamic shear-elasticity-modulus Gd of the base rock showed greater values as the normal stress increased, while Gd decreased and showed the strain dependence as the dynamic shear strain amplitude γ increased; (2) the relationship between Gd and γ was well represented with the equation proposed by Hardin-Drnevich; (3) damping ratio increased as γ increased, and decreased as normal stress increased; (4) When a specimen was about to break, γ suddenly increased, and the dynamic shear strain amplitude at yield point was in the range of approximately (3.4 to 4.1) x 10 -3 . (Wakatsuki, Y.)

  2. Rock suitability classification RSC 2012

    Energy Technology Data Exchange (ETDEWEB)

    McEwen, T. (ed.) [McEwen Consulting, Leicester (United Kingdom); Kapyaho, A. [Geological Survey of Finland, Espoo (Finland); Hella, P. [Saanio and Riekkola, Helsinki (Finland); Aro, S.; Kosunen, P.; Mattila, J.; Pere, T.

    2012-12-15

    This report presents Posiva's Rock Suitability Classification (RSC) system, developed for locating suitable rock volumes for repository design and construction. The RSC system comprises both the revised rock suitability criteria and the procedure for the suitability classification during the construction of the repository. The aim of the classification is to avoid such features of the host rock that may be detrimental to the favourable conditions within the repository, either initially or in the long term. This report also discusses the implications of applying the RSC system for the fulfilment of the regulatory requirements concerning the host rock as a natural barrier and the site's overall suitability for hosting a final repository of spent nuclear fuel.

  3. Rock suitability classification RSC 2012

    International Nuclear Information System (INIS)

    McEwen, T.; Kapyaho, A.; Hella, P.; Aro, S.; Kosunen, P.; Mattila, J.; Pere, T.

    2012-12-01

    This report presents Posiva's Rock Suitability Classification (RSC) system, developed for locating suitable rock volumes for repository design and construction. The RSC system comprises both the revised rock suitability criteria and the procedure for the suitability classification during the construction of the repository. The aim of the classification is to avoid such features of the host rock that may be detrimental to the favourable conditions within the repository, either initially or in the long term. This report also discusses the implications of applying the RSC system for the fulfilment of the regulatory requirements concerning the host rock as a natural barrier and the site's overall suitability for hosting a final repository of spent nuclear fuel

  4. Geostatistical methods for rock mass quality prediction using borehole and geophysical survey data

    Science.gov (United States)

    Chen, J.; Rubin, Y.; Sege, J. E.; Li, X.; Hehua, Z.

    2015-12-01

    For long, deep tunnels, the number of geotechnical borehole investigations during the preconstruction stage is generally limited. Yet tunnels are often constructed in geological structures with complex geometries, and in which the rock mass is fragmented from past structural deformations. Tunnel Geology Prediction (TGP) is a geophysical technique widely used during tunnel construction in China to ensure safety during construction and to prevent geological disasters. In this paper, geostatistical techniques were applied in order to integrate seismic velocity from TGP and borehole information into spatial predictions of RMR (Rock Mass Rating) in unexcavated areas. This approach is intended to apply conditional probability methods to transform seismic velocities to directly observed RMR values. The initial spatial distribution of RMR, inferred from the boreholes, was updated by including geophysical survey data in a co-kriging approach. The method applied to a real tunnel project shows significant improvements in rock mass quality predictions after including geophysical survey data, leading to better decision-making for construction safety design.

  5. Significant population genetic structure detected in the rock bream Oplegnathus fasciatus (Temminck & Schlegel, 1844) inferred from fluorescent-AFLP analysis

    Science.gov (United States)

    Xiao, Yongshuang; Ma, Daoyuan; Xu, Shihong; Liu, Qinghua; Wang, Yanfeng; Xiao, Zhizhong; Li, Jun

    2016-05-01

    Oplegnathus fasciatus (rock bream) is a commercial rocky reef fish species in East Asia that has been considered for aquaculture. We estimated the population genetic diversity and population structure of the species along the coastal waters of China using fluorescent-amplified fragment length polymorphisms technology. Using 53 individuals from three populations and four pairs of selective primers, we amplified 1 264 bands, 98.73% of which were polymorphic. The Zhoushan population showed the highest Nei's genetic diversity and Shannon genetic diversity. The results of analysis of molecular variance (AMOVA) showed that 59.55% of genetic variation existed among populations and 40.45% occurred within populations, which indicated that a significant population genetic structure existed in the species. The pairwise fixation index F st ranged from 0.20 to 0.63 and were significant after sequential Bonferroni correction. The topology of an unweighted pair group method with arithmetic mean tree showed two significant genealogical branches corresponding to the sampling locations of North and South China. The AMOVA and STRUCTURE analyses suggested that the O. fasciatus populations examined should comprise two stocks.

  6. Field evidence for control of quarrying by rock bridges in jointed bedrock

    Science.gov (United States)

    Hooyer, T. S.; Cohen, D. O.; Iverson, N. R.

    2011-12-01

    Quarrying is generally thought to be the most important mechanism by which glaciers erode bedrock. In quarrying models it is assumed that slow, subcritical, growth of pre-existing cracks rate-limits the process and occurs where there are large stress differences in the bed, such as near rock bumps where ice separates from the bed to form water-filled cavities. Owing to the direction of principal stresses in rocks associated with sliding and resultant cavity formation, models predict that quarrying will occur along cracks oriented perpendicular to the ice flow direction or parallel to zones of ice-bed contact. Preglacial cracks in rocks will tend to propagate mainly downward, and in sedimentary or some metamorphic rocks will merge with bedding planes, thereby helping to isolate rock blocks for dislodgement. In contrast to these model assumptions, new measurements of quarried surface orientations in the deglaciated forefield of nine glaciers in Switzerland and Canada indicate a strong correlation between orientations of pre-existing joints and quarried bedrock surfaces, independent of ice flow direction or ice-water contact lines. The strong correlation persists across all rock types, and rocks devoid of major joints lack quarried surfaces. We propose a new conceptual model of quarrying that idealizes the bedrock as a series of blocks separated by discontinuous preglacial joints containing intact rock bridges. Bridges concentrate stress differences caused by normal and shear forces acting at the rock surface. Failure of bridges is caused by slow subcritical crack growth enhanced by water pressure fluctuations. To lend credibility to this new model, we show field evidence of failed rock bridges in quarried surfaces and of rib marks on plumose structures that we interpret as arrest fracture fronts due to transient subglacial water-pressure fluctuations.

  7. Mechanisms and consequences of creep in the nearfield rock of a KBS-3 repository

    International Nuclear Information System (INIS)

    Pusch, R.; Hoekmark, H.

    1992-12-01

    Creep in rock depends on the structure as well as on the stress and temperature. Log time creep is often observed and can be explained on the basis of statistical mechanics. Simple Kelvin behavior can be used as an approximation. The code FLAC is concluded to be useful for predicting creep strain, assuming that the rock obeys the Kelvin law. 22 refs

  8. Rocking pneumonia

    OpenAIRE

    Rijkers, Ger T.; Rodriguez Gomez, Maria

    2017-01-01

    Ever since Chuck Berry coined the term “rocking pneumonia” in his 1956 song “Roll over Beethoven”, pneumonia has been mentioned frequently in modern blues and rock songs. We analyzed the lyrics of these songs to examine how various elements of pneumonia have been represented in popular music, specifically the cause of pneumonia, the risk groups, comorbidity (such as the boogie woogie flu), the clinical symptoms, and treatment and outcome. Up to this day, songwriters suggest that pneumonia is ...

  9. Geomechanics in hard rock mining-Lessons from two case histories

    International Nuclear Information System (INIS)

    Heuze, F.E.

    1982-01-01

    This paper summarizes the geomechanics programs conducted in two hard rock underground mining operations in the Western United States, between 1966 and 1981. The two projects were directed towards understanding the behavior of the rock masses, at the scale of the caverns. To this end, the emphasis was put on large scale field measurements, complemented by limited laboratory testing. The results of these observations were used to build realistic finite element models of the underground chambers. In the marble mine, at Crestmore, California, the models were applied to the structural optimization of the room-and-pillar pattern. In the granite mining, at Climax, Nevada Test Site, the models explained some unusual stress changes observed during excavation. Based on the large number of geomechanical techniques employed, specific conclusions and recommendations are offered regarding the quality, applicability, and usefulness of the various methods. The two case histories clearly indicate that numerical models are extremely useful for a detailed understanding of the structural behavior of mine openings. To be realistic, these models must be based first and foremost on large scale field observations. The lessons learned on these two projects also are directly applicable to the design and analysis of nuclear waste repositories in hard rocks such as basalt, granite, and welded tuff

  10. Examining the relation between rock mass cuttability index and rock drilling properties

    Science.gov (United States)

    Yetkin, Mustafa E.; Özfırat, M. Kemal; Yenice, Hayati; Şimşir, Ferhan; Kahraman, Bayram

    2016-12-01

    Drilling rate is a substantial index value in drilling and excavation operations at mining. It is not only a help in determining physical and mechanical features of rocks, but also delivers strong estimations about instantaneous cutting rates. By this way, work durations to be finished on time, proper machine/equipment selection and efficient excavation works can be achieved. In this study, physical and mechanical properties of surrounding rocks and ore zones are determined by investigations carried out on specimens taken from an underground ore mine. Later, relationships among rock mass classifications, drillability rates, cuttability, and abrasivity have been investigated using multi regression analysis. As a result, equations having high regression rates have been found out among instantaneous cutting rates and geomechanical properties of rocks. Moreover, excavation machine selection for the study area has been made at the best possible interval.

  11. Rock properties data base

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, R.; Gorski, B.; Gyenge, M.

    1991-03-01

    As mining companies proceed deeper and into areas whose stability is threatened by high and complex stress fields, the science of rock mechanics becomes invaluable in designing underground mine strata control programs. CANMET's Mining Research Laboratories division has compiled a summary of pre- and post-failure mechanical properties of rock types which were tested to provide design data. The 'Rock Properties Data Base' presents the results of these tests, and includes many rock types typical of Canadian mine environments. The data base also contains 'm' and 's' values determined using Hoek and Brown's failure criteria for both pre- and post-failure conditions. 7 refs., 3 tabs., 9 figs., 1 append.

  12. Numerical modelling of fluid-rock interactions: Lessons learnt from carbonate rocks diagenesis studies

    Science.gov (United States)

    Nader, Fadi; Bachaud, Pierre; Michel, Anthony

    2015-04-01

    Quantitative assessment of fluid-rock interactions and their impact on carbonate host-rocks has recently become a very attractive research topic within academic and industrial realms. Today, a common operational workflow that aims at predicting the relevant diagenetic processes on the host rocks (i.e. fluid-rock interactions) consists of three main stages: i) constructing a conceptual diagenesis model including inferred preferential fluids pathways; ii) quantifying the resulted diagenetic phases (e.g. depositing cements, dissolved and recrystallized minerals); and iii) numerical modelling of diagenetic processes. Most of the concepts of diagenetic processes operate at the larger, basin-scale, however, the description of the diagenetic phases (products of such processes) and their association with the overall petrophysical evolution of sedimentary rocks remain at reservoir (and even outcrop/ well core) scale. Conceptual models of diagenetic processes are thereafter constructed based on studying surface-exposed rocks and well cores (e.g. petrography, geochemistry, fluid inclusions). We are able to quantify the diagenetic products with various evolving techniques and on varying scales (e.g. point-counting, 2D and 3D image analysis, XRD, micro-CT and pore network models). Geochemical modelling makes use of thermodynamic and kinetic rules as well as data-bases to simulate chemical reactions and fluid-rock interactions. This can be through a 0D model, whereby a certain process is tested (e.g. the likelihood of a certain chemical reaction to operate under specific conditions). Results relate to the fluids and mineral phases involved in the chemical reactions. They could be used as arguments to support or refute proposed outcomes of fluid-rock interactions. Coupling geochemical modelling with transport (reactive transport model; 1D, 2D and 3D) is another possibility, attractive as it provides forward simulations of diagenetic processes and resulting phases. This

  13. Evaluation of dynamic characteristics of hard rock based on numerical simulations of in situ rock tests

    International Nuclear Information System (INIS)

    Yamagami, Yuya; Ikusada, Koji; Jiang, Yujing

    2009-01-01

    In situ rock tests of hard rock of conglomerate in which discontinuities in high angle are dominant were conducted. In this study, in order to confirm the validity of the test results and the test condition, and in order to elucidate the deformation behaviour and the mechanism of shear strength of the rock mass, the numerical simulations of the in situ rock tests by using distinct element method were performed. As a result, it was clarified that the behaviour of the rock mass strongly depends on both geometrical distribution of discontinuities and those mechanical properties. It is thought that a series of evaluation processes showed in this study contribute to improve the reliability of the dynamic characteristic evaluation of the rock mass. (author)

  14. The Mont Terri rock laboratory: International research in the Opalinus Clay

    International Nuclear Information System (INIS)

    Bossart, P.

    2015-01-01

    This article reports on a visit made to the rock laboratory in Mont Terri, Switzerland, where research is being done concerning rock materials that can possibly be used for the implementation of repositories for nuclear wastes. Emphasis is placed on the project’s organisation, rock geology and on-going experiments. International organisations also involved in research on nuclear waste repositories are listed. The research facilities in tunnels built in Opalinus Clay at the Mont Terri site are described. The geology of Opalinus Clay and the structures found in the research tunnels are discussed, as is the hydro-geological setting. The research programme and various institutions involved are listed and experiments carried out are noted. The facilities are now also being used for research on topics related to carbon sequestration

  15. Flathead River Instream Flow Investigation Project : Final Report 1996-2003.

    Energy Technology Data Exchange (ETDEWEB)

    Miller, William J. (Miller Ecological Consultants., Fort Collins, CO); Ptacek, Jonathan A. (Miller Ecological Consultants, Inc., Fort Collins, CO)

    2003-09-01

    A modified Instream Flow Incremental Methodology (IFIM) approach was used on the mainstem Flathead River from the South Fork Flathead River downstream to Flathead Lake. The objective of this study was to quantify changes in habitat for the target fish species, bull trout (Salvelinus confluentus) and west slope cutthroat trout (Oncorhynchus clarki lewisi), as a function of discharge in the river. This approach used a combination of georeferenced field data for each study site combined with a two-dimensional hydraulic simulation of river hydraulic characteristics. The hydraulic simulations were combined with habitat suitability criteria in a GIS analysis format to determine habitat area as a function of discharge. Results of the analysis showed that habitat area is more available at lower discharges than higher discharges and that in comparison of the pre-dam hydrology with post-dam hydrology, the stable pre-dam baseflows provided more stable habitat than the highly variable flow regime during both summer and winter baseflow post-dam periods. The variability week to week and day to day under post-dam conditions waters and dewaters stream margins. This forces sub-adult fish, in particular bull trout, to use less productive habitat during the night. There is a distinct difference between daytime and nighttime habitat use for bull trout sub-adults. The marginal areas that are constantly wet and then dried provide little in productivity for lower trophic levels and consequently become unproductive for higher trophic levels, especially bull trout sub-adults that use those areas as flows increase. A stable flow regime would be more productive than flow regimes with high variability week to week. The highly variable flows likely put stress on a bull trout subadult and west slope cutthroat trout, due to the additional movement required to find suitable habitat. The GIS approach presented here provides both a visual characterization of habitat as well as Arcview project data

  16. Soil/Rock Properties Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Soil/Rock Properties LaboratoryLocation: Spokane SiteThe Soil/Rock Properties Laboratory is contained in the soils bay, a 4,700 sq. ft. facility that provides space...

  17. Rock Cycle Roulette.

    Science.gov (United States)

    Schmidt, Stan M.; Palmer, Courtney

    2000-01-01

    Introduces an activity on the rock cycle. Sets 11 stages representing the transitions of an earth material in the rock cycle. Builds six-sided die for each station, and students move to the stations depending on the rolling side of the die. Evaluates students by discussing several questions in the classroom. Provides instructional information for…

  18. Igneous rocks formed by hypervelocity impact

    Science.gov (United States)

    Osinski, Gordon R.; Grieve, Richard A. F.; Bleacher, Jacob E.; Neish, Catherine D.; Pilles, Eric A.; Tornabene, Livio L.

    2018-03-01

    Igneous rocks are the primary building blocks of planetary crusts. Most igneous rocks originate via decompression melting and/or wet melting of protolith lithologies within planetary interiors and their classification and compositional, petrographic, and textural characteristics, are well-studied. As our exploration of the Solar System continues, so too does the inventory of intrusive and extrusive igneous rocks, settings, and processes. The results of planetary exploration have also clearly demonstrated that impact cratering is a ubiquitous geological process that has affected, and will continue to affect, all planetary objects with a solid surface, whether that be rock or ice. It is now recognized that the production of igneous rocks is a fundamental outcome of hypervelocity impact. The goal of this review is to provide an up-to-date synthesis of our knowledge and understanding of igneous rocks formed by hypervelocity impact. Following a brief overview of the basics of the impact process, we describe how and why melts are generated during impact events and how impact melting differs from endogenic igneous processes. While the process may differ, we show that the products of hypervelocity impact can share close similarities with volcanic and shallow intrusive igneous rocks of endogenic origin. Such impact melt rocks, as they are termed, can display lobate margins and cooling cracks, columnar joints and at the hand specimen and microscopic scale, such rocks can display mineral textures that are typical of volcanic rocks, such as quench crystallites, ophitic, porphyritic, as well as features such as vesicles, flow textures, and so on. Historically, these similarities led to the misidentification of some igneous rocks now known to be impact melt rocks as being of endogenic origin. This raises the question as to how to distinguish between an impact versus an endogenic origin for igneous-like rocks on other planetary bodies where fieldwork and sample analysis may not

  19. Preliminary results of the determination of the Venus rock comsposition by ''Venera 13'' and ''Venera 14'' space probes

    International Nuclear Information System (INIS)

    Surkov, Yu.A.; Moskaleva, L.P.; Shcheglov, O.P.; Kharyukova, V.P.; Manvelyan, O.S.; Smirnov, G.G.

    1982-01-01

    Composition of the rocks on Venus was determined for the first time. The determination of rock composition was carried out at the landing sites of Venera 13 and Venera 14. The rock samples analyzed by the X-ray radiometri.c method. The study of rocks was carried out in most typical of the surface of Venus provinces: rolling upland (Venera 13) and flat lowland (Venera 14). The rock composition at the Venera 13 landing site proved to be close to potassium alkaline basalt, that at the Venera 14 landing site close to tholeitic basalt of the Earth's crust. The comparison of the typical composition of Venus rocks with the composition of rocks of the same structural-morphological provinces of the Earth sws some differences in formation of the surface and the crust of those planets

  20. Potential Cement Phases in Sedimentary Rocks Drilled by Curiosity at Gale Crater, Mars

    Science.gov (United States)

    Rampe, E. B.; Morris, R. V.; Bish, D. L.; Chipera, S. J.; Ming, D. W.; Blake, D. F.; Vaniman, D. T.; Bristow, T. F.; Cavanagh, P.; Farmer, J. D.; hide

    2015-01-01

    The Mars Science Laboratory rover Curiosity has encountered a variety of sedimentary rocks in Gale crater with different grain sizes, diagenetic features, sedimentary structures, and varying degrees of resistance to erosion. Curiosity has drilled three rocks to date and has analyzed the mineralogy, chemical composition, and textures of the samples with the science payload. The drilled rocks are the Sheepbed mudstone at Yellowknife Bay on the plains of Gale crater (John Klein and Cumberland targets), the Dillinger sandstone at the Kimberley on the plains of Gale crater (Windjana target), and a sedimentary unit in the Pahrump Hills in the lowermost rocks at the base of Mt. Sharp (Confidence Hills target). CheMin is the Xray diffractometer on Curiosity, and its data are used to identify and determine the abundance of mineral phases. Secondary phases can tell us about aqueous alteration processes and, thus, can help to elucidate past aqueous environments. Here, we present the secondary mineralogy of the rocks drilled to date as seen by CheMin and discuss past aqueous environments in Gale crater, the potential cementing agents in each rock, and how amorphous materials may play a role in cementing the sediments.

  1. Transporting radioactive rock

    International Nuclear Information System (INIS)

    Pearce, G.

    1990-01-01

    The case is made for exempting geological specimens from the IAEA Regulations for Safer Transport of Radioactive Materials. It is pointed out that many mineral collectors in Devon and Cornwall may be unwittingly infringing these regulations by taking naturally radioactive rocks and specimens containing uranium ores. Even if these collectors are aware that these rocks are radioactive, and many are not, few have the necessary equipment to monitor the activity levels. If the transport regulations were to be enforced alarm could be generated and the regulations devalued in case of an accident. The danger from a spill of rock specimens is negligible compared with an accident involving industrial or medical radioactive substances yet would require similar special treatment. (UK)

  2. Response characteristics of reactor building on weathered soft rock ground

    International Nuclear Information System (INIS)

    Hirata, Kazuta; Tochigi, Hitoshi

    1991-01-01

    The purpose of this study is to investigate the seismic stability of nuclear power plants on layered soft bedrock grounds, focusing on the seismic response of reactor buildings. In this case, the soft bedrock grounds refer to the weathered soft bedrocks with several tens meter thickness overlaying hard bedrocks. Under this condition, there are two subjects regarding the estimation of the seismic response of reactor buildings. One is the estimation of the seismic response of surface ground, and another is the estimation of soil-structure interaction characteristics for the structures embedded in the layered grounds with low impedandce ratio between the surface ground and the bedrock. Paying attention to these subjects, many cases of seismic response analysis were carried out, and the following facts were clarified. In the soft rock grounds overlaying hard bedrocks, it was proved that the response acceleration was larger than the case of uniform hard bedrocks. A simplified sway and rocking model was proposed to consider soil-structure interaction. It was proved that the response of reactor buildings was small when the effect of embedment was considered. (K.I.)

  3. Using small unmanned aerial vehicle for instream habitat evaluation and modelling

    Science.gov (United States)

    Astegiano, Luca; Vezza, Paolo; Comoglio, Claudio; Lingua, Andrea; Spairani, Michele

    2015-04-01

    Recent advances in digital image collection and processing have led to the increased use of unmanned aerial vehicles (UAV) for river research and management. In this paper, we assess the capabilities of a small UAV to characterize physical habitat for fish in three river stretches of North-Western Italy. The main aim of the study was identifying the advantages and challenges of this technology for environmental river management, in the context of the increasing river exploitation for hydropower production. The UAV used to acquire overlapping images was a small quadcopter with a two different high-resolution (non-metric) cameras (Nikon J1™ and Go-Pro Hero 3 Black Edition™). The quadcopter was preprogrammed to fly set waypoints using a small tablet PC. With the acquired imagery, we constructed a 5-cm resolution orthomosaic image and a digital surface model (DSM). The two products were used to map the distribution of aquatic and riparian habitat features, i.e., wetted area, morphological unit distributions, bathymetry, water surface gradient, substrates and grain sizes, shelters and cover for fish. The study assessed the quality of collected data and used such information to identify key reach-scale metrics and important aspects of fluvial morphology and aquatic habitat. The potential and limitations of using UAV for physical habitat survey were evaluated and the collected data were used to initialize and run common habitat simulation tools (MesoHABSIM). Several advantages of using UAV-based imagery were found, including low cost procedures, high resolution and efficiency in data collection. However, some challenges were identified for bathymetry extraction (vegetation obstructions, white waters, turbidity) and grain size assessment (preprocessing of data and automatic object detection). The application domain and possible limitation for instream habitat mapping were defined and will be used as a reference for future studies. Ongoing activities include the

  4. Distribution of rock fragments and their effects on hillslope soil erosion in purple soil, China

    Science.gov (United States)

    Wang, Xiaoyan

    2017-04-01

    influence of rock fragment cover on purple soil slope erosion process were carried on, under different conditions with two kind of rock fragment positions (resting on soil surface and embedded into top soil layer), varied rock fragment coverage (Rc, 0% 40%), two kind of soils with textural porosity or structural porosity, and three kind of rainfall intensities (I, 1 mm/min, 1.5 mm/min and 2 mm/min). Simulated rainfall experiments in situ plots in the field, combined with simulated rainfall experiments in soil pans indoor, were used. The main conclusions of this dissertation are as following: 1. The spatial distribution characteristics of rock fragments in purple soil slope and its effects on the soil physical properties were clarified basically. 2. The mechanism of influence of rock fragments within top soil layer on soil erosion processes was understood and a threshold of rock fragment content on the infiltration was figured out. 3. The relationships between surface rock fragment cover and hillslope soil erosion in purple soil under different conditions with varied rock fragment positions, soil structures and rainfall intensities were obtained and the soil and water conservation function of surface rock fragment cover on reducing soil loss was affirmed.

  5. The Usability of Noise Level from Rock Cutting for the Prediction of Physico-Mechanical Properties of Rocks

    Science.gov (United States)

    Delibalta, M. S.; Kahraman, S.; Comakli, R.

    2015-11-01

    Because the indirect tests are easier and cheaper than the direct tests, the prediction of rock properties from the indirect testing methods is important especially for the preliminary investigations. In this study, the predictability of the physico-mechanical rock properties from the noise level measured during cutting rock with diamond saw was investigated. Noise measurement test, uniaxial compressive strength (UCS) test, Brazilian tensile strength (BTS) test, point load strength (Is) test, density test, and porosity test were carried out on 54 different rock types in the laboratory. The results were statistically analyzed to derive estimation equations. Strong correlations between the noise level and the mechanical rock properties were found. The relations follow power functions. Increasing rock strength increases the noise level. Density and porosity also correlated strongly with the noise level. The relations follow linear functions. Increasing density increases the noise level while increasing porosity decreases the noise level. The developed equations are valid for the rocks with a compressive strength below 150 MPa. Concluding remark is that the physico-mechanical rock properties can reliably be estimated from the noise level measured during cutting the rock with diamond saw.

  6. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 7. Baseline rock properties-basalt

    International Nuclear Information System (INIS)

    1978-04-01

    This volume, Y/OWI/TM-36/7 Baseline Rock Properties--Basalt, is one of a 23-volume series, ''Technical Support for GEIS: Radioactive Waste Isolation in Geologic Formations, Y/OWI/TM-36'' which supplements a ''Contribution to Draft Generic Environmental Impact Statement on Commercial Waste Management: Radioactive Waste Isolation in Geologic Formations, Y/OWI/TM-44.'' The series provides a more complete technical basis for the preconceptual designs, resource requirements, and environmental source terms associated with isolating commercial LWR wastes in underground repositories in salt, granite, shale and basalt. Wastes are considered from three fuel cycles: uranium and plutonium recycling, no recycling of spent fuel and uranium-only recycling. This report contains an evaluation of the results of a literature survey to define the rock mass properties of a generic basalt, which could be considered as a geological medium for storing radioactive waste. The general formation and structure of basaltic rocks is described. This is followed by specific descriptions and rock property data for the Dresser Basalt, the Amchitka Island Basalt, the Nevada Test Site Basalt and the Columbia River Group Basalt. Engineering judgment has been used to derive the rock mass properties of a typical basalt from the relevant intact rock property data and the geological information pertaining to structural defects, such as joints and faults

  7. Deformation style of the Mesozoic sedimentary rocks in southern Thailand

    Science.gov (United States)

    Kanjanapayont, Pitsanupong

    2014-10-01

    Mesozoic sedimentary rocks in southern Thailand are widespread from NNE-SSW and N-S in Chumphon and Trang provinces. The Mesozoic stratigraphic units are the marine Triassic Sai Bon Formation and the non-marine Jurassic-Cretaceous Thung Yai Group, the latter subdivided into Khlong Min, Lam Thap, Sam Chom, and Phun Phin Formations. These units overlie Permian carbonate rocks with an angular unconformity, and are overlain unconformably by Cenozoic units and the Quaternary sediments. The Mesozoic rocks have been folded to form two huge first-ordered syncline or synclinoria, the Chumphon and Surat Thani-Krabi-Trang synclinoria. These synclinoria are elongated in NNE-SSW to N-S direction, and incorporate asymmetric lower-order parasitic folds. The folds have moderately to steeply dipping eastward limbs and more gently dipping westward limbs. These folds were transected by brittle fractures in four major directions. These geologic structures indicate WNW-ESE to E-W contraction with top-to-the-east simple shear at some time before the deposition of the Cenozoic sedimentary units. No major deformation has affected the rocks subsequently, apart from the formation of the fault-controlled Cenozoic basins.

  8. Cataclastic effects in rock salt laboratory and in situ measurements

    International Nuclear Information System (INIS)

    Gramberg, J.; Roest, J.P.A.

    1984-01-01

    The aim of the research is the determination of eventual cataclastic effects in environmental rock salt of a heated part of a vertical deep test bore hole, a model for HLW disposal. Known cataclastic systems from hard rock mining and rock salt mines will form the starting point for the explanation of convergence of underground cavity walls. In rock salt, however, different elements seem to prevail: crystal plasticity and micro-cataclasis. The environmental measurements at the deep bore hole have to be carried out from a distance. To this end the acoustic micro-seismic method will be a suitable one. The appropriate equipment for micro-seismic cross hole measurement is designed, constructed and tested in the laboratory as well as underground. Acoustic velocity data form a crucial point. A micro-seismic acoustic P-wave model, adapted to the process of structural changes, is developed. P-wave velocity measurements in rock salt cubes in the laboratory are described. An underground cross hole measurement in the wall of a gallery with semi-circular section is treated and analysed. A conclusion was that, in this case, no macro-cataclasis (systematic large fractures) will be involved in the process of gallery convergence, but that the mechanism proved to be a combination of crystal plasticity and micro-cataclasis. The same mechanism might be expected to be present in the environmental rock salt of the HLW-disposal deep bore hole. As a result this environmental rock salt might be expected to be impermeable. A plan for the application of the developed equipment during the heating test on the ECN-deep-bore-hole is shown. A theory on ''disking'' or ''rim cracks'' is presented in an annex

  9. Pseudotachylitic breccia in mafic and felsic rocks

    Science.gov (United States)

    Kovaleva, Elizaveta; Huber, Matthew S.

    2017-04-01

    Impact-produced pseudotachylitic breccia (PTB) is abundant in the core of the Vredefort impact structure and was found in many pre-impact lithologies (e.g., Reimold and Colliston, 1994; Gibson et al., 1997). The mechanisms involved in the process of forming this rock remain highly debated, and various authors have discussed many possible models. We investigate PTB from two different rock types: meta-granite and meta-gabbro and test how lithology controls the development of PTB. We also report on clast transport between different lithologies. In the core of the Vredefort impact structure, meta-granite and meta-gabbro are observed in contact with each other, with an extensive set of PTB veins cutting through both lithologies. Microstructural analyses of the PTB veins in thin sections reveals differences between PTBs in meta-granite and meta-gabbro. In granitic samples, PTB often develops along contacts of material with different physical properties, such as a contact with a migmatite or pegmatite vein. Nucleation sites of PTB have features consistent with ductile deformation and shearing, such as sigmoudal-shaped clasts and dragged edges of the veins. Preferential melting of mafic and hydrous minerals takes place (e.g., Reimold and Colliston, 1994; Gibson et al., 2002). Refractory phases remain in the melt as clasts and form reaction rims. In contrast, PTB in meta-gabbro develop in zones with brittle deformation, and do not exploit existing physical contacts. Cataclastic zones develop along the faults and progressively produce ultracataclasites and melt. Thus, PTB veins in meta-gabbro contain fewer clasts. Clasts usually represent multi-phase fragments of host rock and not specific phases. Such fragments often originate from the material trapped between two parallel or horse-tail faults. The lithological control on the development of PTB does not imply that PTB develops independently in different lithologies. We have observed granitic clasts within PTB veins in meta

  10. Location-Related Differences in Weathering Behaviors and Populations of Culturable Rock-Weathering Bacteria Along a Hillside of a Rock Mountain.

    Science.gov (United States)

    Wang, Qi; Wang, Rongrong; He, Linyan; Sheng, Xiafang

    2017-05-01

    Bacteria play important roles in rock weathering, elemental cycling, and soil formation. However, little is known about the weathering potential and population of bacteria inhabiting surfaces of rocks. In this study, we isolated bacteria from the top, middle, and bottom rock samples along a hillside of a rock (trachyte) mountain as well as adjacent soils and characterized rock-weathering behaviors and populations of the bacteria. Per gram of rock or surface soil, 10 6 -10 7 colony forming units were obtained and total 192 bacteria were isolated. Laboratory rock dissolution experiments indicated that the proportions of the highly effective Fe (ranging from 67 to 92 %), Al (ranging from 40 to 48 %), and Cu (ranging from 54 to 81 %) solubilizers were significantly higher in the top rock and soil samples, while the proportion of the highly effective Si (56 %) solubilizers was significantly higher in the middle rock samples. Furthermore, 78, 96, and 6 % of bacteria from the top rocks, soils, and middle rocks, respectively, significantly acidified the culture medium (pH bacteria (79 %) from the rocks were different to those from the soils and most of them (species level) have not been previously reported. Furthermore, location-specific rock-weathering bacterial populations were found and Bacillus species were the most (66 %) frequently isolated rock-weathering bacteria in the rocks based on cultivation methods. Notably, the top rocks and soils had the highest and lowest diversity of rock-weathering bacterial populations, respectively. The results suggested location-related differences in element (Si, Al, Fe, and Cu) releasing effectiveness and communities of rock-weathering bacteria along the hillside of the rock mountain.

  11. PRINCIPLE ROCK TYPES FOR RADIOACTIVE WASTE REPOSITORIES

    Directory of Open Access Journals (Sweden)

    Sibila Borojević Šostarić

    2012-07-01

    Full Text Available Underground geological storage of high- and intermediate/low radioactive waste is aimed to represent a barrier between the surface environment and potentially hazardous radioactive elements. Permeability, behavior against external stresses, chemical reacatibility and absorption are the key geological parameters for the geological storage of radioactive waste. Three principal rock types were discussed and applied to the Dinarides: (1 evaporites in general, (2 shale, and (3 crystalline basement rocks. (1 Within the Dinarides, evaporite formations are located within the central part of a Carbonate platform and are inappropriate for storage. Offshore evaporites are located within diapiric structures of the central and southern part of the Adriatic Sea and are covered by thick Mesozoic to Cenozoic clastic sediment. Under very specific circumstances they can be considered as potential site locations for further investigation for the storage of low/intermediate level radioactive wast e. (2 Thick flysch type formation of shale to phyllite rocks are exposed at the basement units of the Petrova and Trgovska gora regions whereas (3 crystalline magmatic to metamorphic basement is exposed at the Moslavačka Gora and Slavonian Mts. regions. For high-level radioactive waste, basement phyllites and granites may represent the only realistic potential option in the NW Dinarides.

  12. The analysis of creep characteristics of the surrounding rock of the carbonaceous rock tunnel based on Singh-Mitchell model

    Science.gov (United States)

    Luo, Junhui; Mi, Decai; Ye, Qiongyao; Deng, Shengqiang; Zeng, Fuquan; Zeng, Yongjun

    2018-01-01

    Carbonaceous rock has the characteristics of easy disintegration, softening, swelling and environmental sensitivity, which belongs to soft surrounding rock, and the deformation during excavation and long-term stability of the surrounding rock of carbonaceous rock tunnel are common problems in the construction of carbonaceous rock tunnel. According to the above, the Monitor and measure the displacement, temperature and osmotic pressure of the surrounding carbonaceous rock of the tunnel of Guangxi Hebai highway. Then it based on the obtaining data to study the creep mechanism of surrounding rock using Singh-Mitchell model and predict the deformation of surrounding rock before the tunnel is operation. The results show that the Singh-Mitchell creep model can effectively analyse and predict the deformation development law of surrounding rock of tunnel without considering temperature and osmotic pressure, it can provide reference for the construction of carbonaceous rock tunnel and the measures to prevent and reinforce it..

  13. Experimental Rock-on-Rock Abrasive Wear Under Aqueous Conditions: its Role in Subglacial Abrasion

    Science.gov (United States)

    Rutter, E. H.; Lee, A. G.

    2003-12-01

    We have determined experimentally the rate of abrasive wear of rock on rock for a range of rock types as a function of normal stress and shear displacement. Unlike abrasive wear in fault zones, where wear products accumulate as a thickening gouge zone, in our experiments wear particles were removed by flowing water. The experiments are thus directly pertinent to one of the most important processes in subglacial erosion, and to some extent in river incision. Wear was produced between rotating discs machined from rock samples and measured from the progressive approach of the disc axes towards each other under various levels of normal load. Shear displacements of several km were produced. Optical and scanning electron microscopy were used to study the worn rock surfaces, and particle size distributions in wear products were characterized using a laser particle size analyzer. Rock types studied were sandstones of various porosities and cement characteristics, schists and a granite. In all cases abrasion rate decreased logarithmically with displacement by up to 2 orders of magnitude until a steady state was approached, but only after at least 1 km displacement. The more porous, less-well cemented rocks wore fastest. Amount of abrasion could be characterized quantitatively using an exponentially decaying plus a steady-state term. Wear rate increased non-linearly with normal contact stress, apparently to an asymptote defined by the unconfined compressive strength. Microstructural study showed that the well-cemented and/or lowest porosity rocks wore by progressive abrasion of grains without plucking, whereas whole grains were plucked out of weakly-cemented and/or more porous rocks. This difference in behavior was reflected in wear-product particle size distributions. Where whole-grain plucking was possible, wear products were dominated by particles of the original grain size rather than finer rock flour. Comparison of our results to glacier basal abrasive wear estimated

  14. Research in rock deformation: Report of the Second Rock Deformation Colloquium, 1989 AGU Spring Meeting

    Science.gov (United States)

    Green, Harry

    In response to the considerable interest expressed at the first Rock Deformation Colloquium held at the Fall 1988 AGU meeting in San Francisco, a second dinner meeting was held on Monday evening, May 8, 1989, at the Omni Hotel in Baltimore. The principal business items were a report by Steve Kirby (U.S. Geological Survey, Menlo Park, Calif.) concerning the meeting the previous day of the rock deformation steering committee and an after dinner presentation by Steve Freiman of the National Institute of Standards and Technology in Gaithersburg, Md., entitled “The Environmental Effects on Subcritical Crack Growth.” Kirby reported that a technical committee for rock deformation has been established within the Tectonophysics Section of AGU; the steering committee will attempt to establish constructive working relations with allied societies and disciplines, such as ceramics, metallurgy, materials science, structural geology, and surface science. Brian Evans of the Massachusetts Institute of Technology in Cambridge, Terry Tullis of Brown University in Providence, R.I., and Harry Green of the University of California at Davis agreed to be a subcommittee to propose a name for the technical committee, for discussion at the next steering committee meeting to be held before the 1989 Fall AGU meeting. Green also agreed to investigate the possibility of convening a special session at the Fall Meeting on the nature and mechanism of deep-focus earthquakes. (The session is Deep Slab Deformation and Faulting, T21B and T22A, organized by Harry and Ken Creager of the University of Washington, Seattle; it will be all day on Tuesday, December 5.)

  15. The physical principles of rock magnetism

    CERN Document Server

    Stacey, Frank

    1974-01-01

    Developments in Solid Earth Geophysics 5: The Physical Principles of Rock Magnetism explores the physical principles of rock magnetism, with emphasis on the properties of finely divided magnetic materials. It discusses the origin and stability of rock magnetizations, the role of remanent magnetism in interpreting magnetic surveys, magnetic anisotropy as an indicator of rock fabric, and the relationship between piezomagnetic changes and seismic activity. Organized into 13 chapters, this volume discusses the properties of solids, magnetite and hematite grains, and rocks with magnetite grains

  16. Rock coasts and seabird breeding sites : a common optimization

    Science.gov (United States)

    Marie, Eveillard-Buchoux

    2014-05-01

    The North-West coasts of Europe support a lot of part of Northern hemisphere breeding seabirds. In that context, Scotland has a preponderant place and Brittany has southernmost limit of these species areas, for most of them. Outside the breeding season these species live mainly on the open sea and when they do visit the land to breed, they nest on a specific sites : almost all the time they breed on the rock coasts, often on seacliffs. This specific habitat are defines by geomorphological characteristics which offer special forms of the coast. The forms of rock coasts are originally and different because of several proprieties of geology, of lithology, of structures. Breeding seabird, occupying these sites, reveals, in a new light, the richness of these forms and the originals geographic location of the coastline : seabirds prefer nest in exposed coastline like rock caps, rocky points or islands. Seabirds and rock coasts are research topics in environmental geography since several years. However, these combination studies is a new approach in this field and enlargement in the heritage field allows supplement scientific approach. For example, it show that in most important touristic sites, environmental protection measures focused on landscape, habitat or bird, but much more rarely on rock coasts for these intrinsic values. Indeed, in Brittany or in Scotland, seabirds are often stars species in lot of coastal nature reserves, where they're considered like greater ecological heritage. We could see it in touristic promotion field : bird is everywhere, cliff is mostly kept in the dark, as well in leaflets as in speech visitor's guides - without, for example, as a part of this landscape. In all cases, combination of these two heritages is extremely rare. Yet, this current research illustrates the interest and the issue of development of this comparative approach seabirds / rock coasts for optimization of nature tourism and geotourism.

  17. 30 CFR 57.3461 - Rock bursts.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Rock bursts. 57.3461 Section 57.3461 Mineral...-Underground Only § 57.3461 Rock bursts. (a) Operators of mines which have experienced a rock burst shall— (1) Within twenty four hours report to the nearest MSHA office each rock burst which: (i) Causes persons to...

  18. Sorption of cesium in intact rock

    International Nuclear Information System (INIS)

    Puukko, E.

    2014-04-01

    The mass distribution coefficient K d is used in performance assessment (PA) to describe sorption of a radionuclide on rock. The R d is determined using crushed rock which causes uncertainty in converting the R d values to K d values for intact rock. This work describes a method to determine the equilibrium of sorption on intact rock. The rock types of the planned Olkiluoto waste disposal site were T-series mica gneiss (T-MGN), T-series tonalite granodiorite granite gneiss (T-TGG), P-series tonalite granodiorite granite gneiss (P-TGG) and pegmatitic granite (PGR). These rocks contain different amount of biotite which is the main sorbing mineral. The sorption of cesium on intact rock slices was studied by applying an electrical field to speed up migration of cesium into the rock. Cesium is in the solution as a noncomplex cation Cs + and it is sorbed by ion exchange. The tracer used in the experiments was 134 Cs. The experimental sorption on the intact rock is compared with values calculated using the in house cation exchange sorption model (HYRL model) in PHREEQC program. The observed sorption on T-MGN and T-TGG rocks was close to the calculated values. Two PGR samples were from a depth of 70 m and three samples were from a depth of 150 m. Cesium sorbed more than predicted on the two 70 m PGR samples. The sorption of Cs on the three 150 m PGR samples was small which was consistent with the calculations. The pegmatitic granite PGR has the smallest content of biotite of the four rock types. In the case of P-TGG rock the observed values of sorption were only half of the calculated values. Two kind of slices were cut from P-TGG drill core. The slices were against and to the direction of the foliation of the biotite rims. The sorption of cesium on P-TGG rock was same in both cases. The results indicated that there was no effect of the directions of the electric field and the foliation of biotite in the P-TGG rock. (orig.)

  19. Creep in crystalline rock with application to high level nuclear waste repository

    International Nuclear Information System (INIS)

    Eloranta, P.; Simonen, A.

    1992-06-01

    The time-dependent strength and deformation properties of hard crystalline rock are studied. Theoretical models defining the phenomena which can effect these properties are reviewed. The time- dependent deformation of the openings in the proposed nuclear waste repository is analysed. The most important factors affecting the subcritical crack growth in crystalline rock are the stress state, the chemical environment, temperature and microstructure of the rock. There are several theoretical models for the analysis of creep and cyclic fatigue: deformation diagrams, rheological models thermodynamic models, reaction rate models, stochastic models, damage models and time-dependent safety factor model. They are defective in describing the three-axial stress condition and strength criteria. In addition, the required parameters are often too difficult to determine with adequate accuracy. Therefore these models are seldom applied in practice. The effect of microcrack- driven creep on the stability of the work shaft, the emplacement tunnel and the capsulation hole of a proposed nuclear waste repository was studied using a numerical model developed by Atomic Energy of Canada Ltd. According to the model, the microcrack driven creep progresses very slowly in good quality rock. Poor rock quality may accelerate the creep rate. The model is very sensitive to the properties of the rock and secondary stress state. The results show that creep causes no stability problems on excavations in good rock. The results overestimate the effect of the creep, because the analysis omitted the effect of support structures and backfilling

  20. Investigations into stress shell characteristics of surrounding rock in fully mechanized top-coal caving face

    Energy Technology Data Exchange (ETDEWEB)

    Xie, G.X.; Chang, J.C.; Yang, K. [Anhui University of Science and Technology, Huainan (China)

    2009-01-15

    A key issue in underground mining is to understand and master the evolving patterns of stress induced by mining, and to control and utilize the action of rock pressure. Numerical and physical modeling tests have been carried out to investigate the distribution patterns of stress in the rock surrounding a fully mechanized top-coal caving (FMTC) face. The results showed that a macro-stress shell composed of high stress exists in the rock surrounding an FMTC face. The stress of the shell is higher than its internal and external stress and the stresses at its skewback producing abutment pressure for the surrounding rock. The stress shell lies in the virgin coal and rock mass in the vicinity of the face and its sagging zone. The stress shell, which bears and transfers the loads of overlying strata, acts as the primary supporting system of forces, and is the corpus of characterizing three-dimensional and macro-rock pressure distribution of mining face. Its external and internal shape changes with the variations in the working face structure as the face advances. Within the low-stress zone inside the stress shell, another structure, i.e. voussoir beam, which only bears parts of the load from the lower-lying strata, will produce periodic pressures on the face instead of great dynamic pressure even if the beam ruptures and loses stability. The results show that the FMTC face is situated within the lower-stress zone, which is protected by the stress shell of the overlying surrounding rock. We give an explanation of lower occurrence of rock pressure on FMTC faces, and reveal the mechanical nature of the top coal of an FMTC face acting as a 'cushion'. The strata behaviors of the face and its neighboring gates are under control of the stress shell. Drastic rock pressure in mine may occur when the balance of the stress shell is destruction or the forces system of the stress shell transfers. Crown Copyright

  1. The Relationship between Mechanical Properties and Gradual Deterioration of Microstructures of Rock Mass Subject to Freeze-thaw Cycles

    Directory of Open Access Journals (Sweden)

    Haibo Jiang

    2018-01-01

    Full Text Available Under freeze-thaw cycles, the relationship between rock microstructure deterioration and its macroscopic mechanical characteristics has drawn extensive attention from engineers. With the objective to incorporate freeze-thaw cycle experiment into headrace tunnel engineering, in the present study two groups of andesite rock samples in different states are tested under the conditions of the lowest freezing temperature of –40 ℃ and the thawing temperature of 20 ℃. Damage detection was performed by magnetic resonance imaging for the interior microstructure of rock samples subject to different freeze-thaw cycles, and the relationship between the sample mechanical properties and gradual deterioration of rock microstructures was discussed. The results demonstrate evident influence of freeze-thaw cycle on the damage and deterioration of internal pore structure in andesite, and the rock uniaxial compressive strength and elasticity modulus exhibit a decreasing trend with the increase of freeze-thaw cycles. After 40 cycles, the strength of naturally saturated rock samples decreases by 39.4% (equivalent to 69.4 MPa and the elasticity modulus drops by 47.46% (equivalent to 3.27 GPa. For rock samples saturated by vacuum, 40 freeze-thaw cycles lead to a decrease of 36.86% (equivalent to 58.2 MPa in rock strength and a drop of 44.85% (equivalent to 2.83 GPa in elasticity modulus. Therefore, the test results quantitatively elucidate the substantial influence of freeze-thaw cycle on the damage and deterioration of internal structure in andesite.

  2. Measurements of thermal properties of rocks

    International Nuclear Information System (INIS)

    Kumada, Toshiaki

    2001-02-01

    The report concerns the measurement of thermal conductivity and specific heat of supplied sedimental rock B and Funyu rock. The method of measurement of these properties was done with the method which was developed at 1997 and improved much in its accuracy by the present author et al. The porosity of sedimental rock B is 0.55, which is deduced from the density of rock (the porosity deduced from the difference between dry and water filled conditions is 0.42) and the shape and size of pores in rock are much different. Its thermal conductivity is 0.238 W/mK in dry and 1.152 W/mK in water filled conditions respectively, while the thermal conductivity of bentonite is 0.238 W/mK in dry and 1.152 W/mK in water saturated conditions. The difference of thermal conductivity between dry and water saturated conditions is little difference in sedimental rock B and bentonite at same porosity. The porosity of Funyu rock is 0.26 and the shape and size of pores in the rock are uniform. Its thermal conductivity is 0.914 W/mK in dry and 1.405 W/mK in water saturated conditions, while the thermal conductivity of bentonite is 0.606 W/mK in dry and 1.591 W/mK in water saturated conditions respectively. The correlation estimating thermal conductivity of rocks was derived based on Fricke correlation by presuming rocks as a suspension. (author)

  3. Mechanism of rock shattering by explosions, depending on the nature of jointing and the elastic state

    Energy Technology Data Exchange (ETDEWEB)

    Mosinets, V N

    1966-01-01

    For proper use of explosives in shattering rock it is necessary to understand the mechanism of shattering. To a great extent this mechanism of shattering is controlled by fracturing in the rock and by the elastic properties of the rock. The processes of shattering as a result of explosion are analyzed, and the conclusion is made that, in its general interpretation, the mechanism of shattering is merely of theoretical interest. The applicability to actual media changes according to structure of the medium. Relatively massive rocks are characterized by an asymmetrical distribution function of the joints and micro-fractures and other inhomogeneities, the mode being shifted to the left of the asymmetry center. Rocks cut by an extensive network of microfractures and joints are characterized by an approximately normal distribution function; rocks cut by large joints have an asymmetrical distribution function, with the mode shifted to the right of the asymmetry center.

  4. Mining technology development for hard rock excavation

    International Nuclear Information System (INIS)

    Hustrulid, W.; Cudnick, R.; Trent, R.; Holmberg, R.

    1980-01-01

    A research facility has been established in the granitic gneiss of the CSM Experimental Mine at Idaho Springs, Colorado, for the purpose of evaluating/developing mining, geologic and geotechnical procedures appropriate for use in establishing nuclear waste repositories in hard rock. An experimental room has been excavated using careful blasting procedures. The extent and magnitude of blast damage is being evaluated. Structural geology is being mapped to assess continuity

  5. Semantic modeling of the structural and process entities during plastic deformation of crystals and rocks

    Science.gov (United States)

    Babaie, Hassan; Davarpanah, Armita

    2016-04-01

    We are semantically modeling the structural and dynamic process components of the plastic deformation of minerals and rocks in the Plastic Deformation Ontology (PDO). Applying the Ontology of Physics in Biology, the PDO classifies the spatial entities that participate in the diverse processes of plastic deformation into the Physical_Plastic_Deformation_Entity and Nonphysical_Plastic_Deformation_Entity classes. The Material_Physical_Plastic_Deformation_Entity class includes things such as microstructures, lattice defects, atoms, liquid, and grain boundaries, and the Immaterial_Physical_Plastic_Deformation_Entity class includes vacancies in crystals and voids along mineral grain boundaries. The objects under the many subclasses of these classes (e.g., crystal, lattice defect, layering) have spatial parts that are related to each other through taxonomic (e.g., Line_Defect isA Lattice_Defect), structural (mereological, e.g., Twin_Plane partOf Twin), spatial-topological (e.g., Vacancy adjacentTo Atom, Fluid locatedAlong Grain_Boundary), and domain specific (e.g., displaces, Fluid crystallizes Dissolved_Ion, Void existsAlong Grain_Boundary) relationships. The dynamic aspect of the plastic deformation is modeled under the dynamical Process_Entity class that subsumes classes such as Recrystallization and Pressure_Solution that define the flow of energy amongst the physical entities. The values of the dynamical state properties of the physical entities (e.g., Chemical_Potential, Temperature, Particle_Velocity) change while they take part in the deformational processes such as Diffusion and Dislocation_Glide. The process entities have temporal parts (phases) that are related to each other through temporal relations such as precedes, isSubprocessOf, and overlaps. The properties of the physical entities, defined under the Physical_Property class, change as they participate in the plastic deformational processes. The properties are categorized into dynamical, constitutive

  6. Multiverso: Rock'n'Astronomy

    Science.gov (United States)

    Caballero, J. A.

    2012-05-01

    In the last few years, there have been several projects involving astronomy and classical music. But have a rock band ever appeared at a science conference or an astronomer at a rock concert? We present a project, Multiverso, in which we mix rock and astronomy, together with poetry and video art (Caballero, 2010). The project started in late 2009 and has already reached tens of thousands people in Spain through the release of an album, several concert-talks, television, radio, newspapers and the internet.

  7. Strength Assessment of Broken Rock Postgrouting Reinforcement Based on Initial Broken Rock Quality and Grouting Quality

    Directory of Open Access Journals (Sweden)

    Hongfa Xu

    2017-01-01

    Full Text Available To estimate postgrouting rock mass strength growth is important for engineering design. In this paper, using self-developed indoor pressure-grouting devices, 19 groups of test cubic blocks were made of the different water cement ratio grouting into the broken rock of three kinds of particle sizes. The shear strength parameters of each group under different conditions were tested. Then this paper presents a quantitative calculation method for predicting the strength growth of grouted broken rock. Relational equations were developed to investigate the relationship between the growth rates of uniaxial compressive strength (UCS, absolute value of uniaxial tensile strength (AUTS, internal friction angle, and cohesion for post- to pregrouting broken rock based on Mohr-Coulomb strength criterion. From previous test data, the empirical equation between the growth rate of UCS and the ratio of the initial rock mass UCS to the grout concretion UCS has been determined. The equations of the growth rates of the internal friction coefficient and UCS for grouting broken rock with rock mass rating (RMR and its increment have been established. The calculated results are consistent with the experimental results. These observations are important for engineered design of grouting reinforcement for broken rock mass.

  8. Preliminary Geophysical Investigations of the Ship Rock Diatreme, Navajo Nation, New Mexico

    Science.gov (United States)

    Gruen, E. M.; McCarthy, L.; Namingha, G.; Bank, C.; Noblett, J.; Semken, S.

    2003-12-01

    Magnetic and gravity data were collected at the Ship Rock minette neck and dikes, part of the Navajo volcanic field in the central Colorado Plateau, to investigate their subsurface structure. The deep root system of Ship Rock, an exhumed Oligocene maar-diatreme complex, has not been resolved. The diatreme is largely composed of minette tuff-breccia with a large wallrock fraction, whereas the dikes are composed of hypabyssal minette. The country rock is the Upper Cretaceous Mancos Shale. Density and magnetic contrasts between the igneous rock and surrounding shale suggest that the buried structure of Ship Rock can be imaged. Preliminary geophysical investigations were carried out in order to test this hypothesis. We collected magnetic and gravitational data along four lines selected to transect the major south and northeast dikes and to partly encircle the diatreme. Modeling differently sized, oriented and shaped intrusions, we created theoretical Free Air anomaly curves to try to match the two clearest anomalies. Modeling necessitates (i) that the major north-south dike dips west and (ii) the presence of a high-density, deep body near the diatreme. The Free Air anomaly curves show that smaller dikes might not be detected from gravity data; however, they are necessary to determine the presence of large, dense bodies. Although not modeled, the magnetics curves show that smaller dikes can easily be detected. Our study results are promising, and we plan a more thorough investigation in the future which will produce a magnetic map to determine if further buried dikes exist in the vicinity, and measure gravity along additional profiles to better constrain the location of the dense body at depth.

  9. Rock slope design guide.

    Science.gov (United States)

    2011-04-01

    This Manual is intended to provide guidance for the design of rock cut slopes, rockfall catchment, and : rockfall controls. Recommendations presented in this manual are based on research presented in Shakoor : and Admassu (2010) entitled Rock Slop...

  10. Rock Slope Design Criteria

    Science.gov (United States)

    2010-06-01

    Based on the stratigraphy and the type of slope stability problems, the flat lying, Paleozoic age, sedimentary : rocks of Ohio were divided into three design units: 1) competent rock design unit consisting of sandstones, limestones, : and siltstones ...

  11. Source rock potential of middle cretaceous rocks in Southwestern Montana

    Science.gov (United States)

    Dyman, T.S.; Palacas, J.G.; Tysdal, R.G.; Perry, W.J.; Pawlewicz, M.J.

    1996-01-01

    The middle Cretaceous in southwestern Montana is composed of a marine and nonmarine succession of predominantly clastic rocks that were deposited along the western margin of the Western Interior Seaway. In places, middle Cretaceous rocks contain appreciable total organic carbon (TOC), such as 5.59% for the Mowry Shale and 8.11% for the Frontier Formation in the Madison Range. Most samples, however, exhibit less than 1.0% TOC. The genetic or hydrocarbon potential (S1+S2) of all the samples analyzed, except one, yield less than 1 mg HC/g rock, strongly indicating poor potential for generating commercial amounts of hydrocarbons. Out of 51 samples analyzed, only one (a Thermopolis Shale sample from the Snowcrest Range) showed a moderate petroleum potential of 3.1 mg HC/g rock. Most of the middle Cretaceous samples are thermally immature to marginally mature, with vitrinite reflectance ranging from about 0.4 to 0.6% Ro. Maturity is high in the Pioneer Mountains, where vitrinite reflectance averages 3.4% Ro, and at Big Sky Montana, where vitrinite reflectance averages 2.5% Ro. At both localities, high Ro values are due to local heat sources, such as the Pioneer batholith in the Pioneer Mountains.

  12. Impact of grain size and rock composition on simulated rock weathering

    Science.gov (United States)

    Israeli, Yoni; Emmanuel, Simon

    2018-05-01

    Both chemical and mechanical processes act together to control the weath