The influence of spatial variability of lithological and morphometric characters on drainage network arrangement

Science.gov (United States)

Coco, Laura; Buccolini, Marcello

2015-04-01

Several factors control the spatial setting and temporal development of the drainage systems: climate, sea level changes, lithology, tectonics, morphometry, land use and land cover. The present work deals with the role of spatial variability of lithology and morphometry on drainage networks arrangement and presents some preliminary evaluations. The test area was the Periadriatic belt of central Italy, composed of Plio-Pleistocene foredeep succession (clay, sands and conglomerate) arranged in a northeastern vergence monocline. We analyzed 37 small basins directly flowing in the Adriatic Sea (18 in Abruzzi and 19 in Marche Region) that have homogenous climatic, eustatic, tectonic, land use and land cover features. For this reason, we could focus our research on lithology and morphometry. We used 10 m cell-size Italian DEM (TINITALY) supplying by INGV (National Institute of Geophysics and Volcanology) [from http://tinitaly.pi.ingv.it/] as source of morphometric data, and extracted watersheds and stream networks through an automatic procedure included in TauDEM toolbox within ArcGIS 9.3 [freely downloaded from http://hydrology.usu.edu/taudem/taudem5/index.html]. For each drainage basin, we reconstructed the topography prior to the inception of fluvial incision through the Topo-to-Raster interpolation tool, considering the heights of the watershed divide as elevation points and obtaining the pre-incision DEM in which the fluvial valleys resulted filled. On this DEM, we calculated the Morphometric Slope Index (MSI), developed by Buccolini et al. (2012), using the formula M SI = Rc -L -Ar/A2D in which Rc is circularity ratio, L is slope length, A2D and Ar are plane and surface area, respectively. In particular, Ar represents the three-dimensional area calculated on the pre-incision DEM. This index is a unique reference index for basin morphometry including both areal and linear features, such as size, shape, inclination, length and width. As drainage network parameter we

The Relationship Between Lithology and Slope Morphology in the Tucson Mountains, Arizona.

Directory of Open Access Journals (Sweden)

Kamel Khanchoul

2008-05-01

Full Text Available The relationship between lithology and slope morphology is investigated at eight sites on granitic, andesitic, andsedimentary hillslopes in the Tucson Mountains, Arizona. Several methods are used in the study. Topographic profi lesare constructed. Skewness indices, slope length, and mean slope angles of the different slope profi les are computed andcompared with each other. Debris size analysis has permitted for some profi les, the determination of hillfront/piedmontjunctions. The nature and structural characteristics of the bedrock are the ones that determine the hillslope morphologyin this semi-arid region. There are, as a matter of fact, variations in profi les on the same bedrock nature but differentlyexposed. More precise morphologic studies have been also done in comparing the different lithologic pairs. They havepermitted to show some similarities in shapes. The granitic-andesitic slopes and andesiic-sedimentary slopes are thebest comparisons which show the relationship between lithology and slope morphology. The granitic-sedimentary sloperelationship is shown in the hillfront concavities, mountain front and piedmont mean slope angles.

Influence of Aggregate Wettability with Different Lithology Aggregates on Concrete Drying Shrinkage

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Yuanchen Guo

2015-01-01

Full Text Available The correlation of the wettability of different lithology aggregates and the drying shrinkage of concrete materials is studied, and some influential factors such as wettability and wetting angle are analyzed. A mercury porosimeter is used to measure the porosities of different lithology aggregates accurately, and the pore size ranges that significantly affect the drying shrinkage of different lithology aggregate concretes are confirmed. The pore distribution curve of the different coarse aggregates is also measured through a statistical method, and the contact angle of different coarse aggregates and concrete is calculated according to the linear fitting relationship. Research shows that concrete strength is determined by aggregate strength. Aggregate wettability is not directly correlated with concrete strength, but wettability significantly affects concrete drying shrinkage. In all types’ pores, the greatest impacts on wettability are capillary pores and gel pores, especially for the pores of the size locating 2.5–50 nm and 50–100 nm two ranges.

Application of element logging to lithologic identification of key horizons in Sichuan–Chongqing gas provinces

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Ping Yin

2018-03-01

Full Text Available With the popularization and application of fast drilling technology in Sichuan–Chongqing gas provinces, the returned cuttings are fine and even powdered, so the traditional cutting lithology identification methods are not applicable any longer. In this paper, qualitative lithology identification and quantitative interpretation based on element logging were conducted on the key oil and gas bearing layers in this area according to the principle of elemental geochemistry. The study results show that: (1 different lithologies can be identified easily because of their different element logging characteristics. For example, basalts have the element characteristics of 0.35 0.55. (2 Clastic rocks, carbonate rocks, sulphate and transition rocks in the category of sedimentary rocks can be identified based on the element combination of (Al + Si + Fe and (Ca + Mg + S. Among them, clastic rocks have (Al + Si + Fe >31%, carbonate rocks have (Al + Si + Fe 36%. (3 Then, based on the element combination of (Si + K + Ca+Si/Al and (Al + Si + Fe + K+(Ca + S/Mg, sandstone, mudstone (shale, gypsum, dolomite, limestone and transition rocks can be identified. Finally, a qualitative identification chart and a set of quantitative interpretation software of element logging on key horizons in Sichuan–Chongqing gas provinces were developed to make this method convenient for field application. This method was applied on site in ten wells (such as Well MX207 in Sichuan–Chongqing gas provinces. It is indicated that the coincidence rate of lithology identification is in the range of 88.75–95.22% (averaging 92.42%. Obviously, it can satisfy the requirements of fast lithology identification while drilling of key oil and gas horizons in Sichuan–Chongqing gas provinces. Keywords: Sichuan–Chongqing gas provinces, Key horizon, Element logging, Lithologic identification while drilling, Quantitative lithologic interpretation, Qualitative

Interrelationship of density and lithological characteristics of intersaline deposits of the Pripyatskiy basin

Energy Technology Data Exchange (ETDEWEB)

Anpilogov, A.P.; Bulyga, V.Kh.; Ksenofontov, V.A.; Ur' yev, I.I.

1980-01-01

Based on materials of lithological study and zoning of the lower Zadonskiy, upper Zadonskiy and Yeletskiy deposits of the Pripyatskiy basin with regard for the depth of occurrence of the rocks, a map was compiled for isodensities of the intersaline complex. Variability in the values of density over the area and the total correspondence of the configuration of isodens to the extent of the lithological fields and the main geostructural elements are established.

Lithology identification of aquifers from geophysical well logs and fuzzy logic analysis: Shui-Lin Area, Taiwan

Science.gov (United States)

Hsieh, Bieng-Zih; Lewis, Charles; Lin, Zsay-Shing

2005-04-01

The purpose of this study is to construct a fuzzy lithology system from well logs to identify formation lithology of a groundwater aquifer system in order to better apply conventional well logging interpretation in hydro-geologic studies because well log responses of aquifers are sometimes different from those of conventional oil and gas reservoirs. The input variables for this system are the gamma-ray log reading, the separation between the spherically focused resistivity and the deep very-enhanced resistivity curves, and the borehole compensated sonic log reading. The output variable is groundwater formation lithology. All linguistic variables are based on five linguistic terms with a trapezoidal membership function. In this study, 50 data sets are clustered into 40 training sets and 10 testing sets for constructing the fuzzy lithology system and validating the ability of system prediction, respectively. The rule-based database containing 12 fuzzy lithology rules is developed from the training data sets, and the rule strength is weighted. A Madani inference system and the bisector of area defuzzification method are used for fuzzy inference and defuzzification. The success of training performance and the prediction ability were both 90%, with the calculated correlation of training and testing equal to 0.925 and 0.928, respectively. Well logs and core data from a clastic aquifer (depths 100-198 m) in the Shui-Lin area of west-central Taiwan are used for testing the system's construction. Comparison of results from core analysis, well logging and the fuzzy lithology system indicates that even though the well logging method can easily define a permeable sand formation, distinguishing between silts and sands and determining grain size variation in sands is more subjective. These shortcomings can be improved by a fuzzy lithology system that is able to yield more objective decisions than some conventional methods of log interpretation.

Lithology and Bedrock Geotechnical Properties in Controlling Rock and Ice Mass Movements in Mountain Cryosphere

Science.gov (United States)

Karki, A.; Kargel, J. S.

2017-12-01

Landslides and ice avalanches kill >5000 people annually (D. Petley, 2012, Geology http://dx.doi.org/10.1130/G33217.1); destroy or damage homes and infrastructure; and create secondary hazards, such as flooding due to blocked rivers. Critical roles of surface slope, earthquake shaking, soil characteristics and saturation, river erosional undercutting, rainfall intensity, snow loading, permafrost thaw, freeze-thaw and frost shattering, debuttressing of unstable masses due to glacier thinning, and vegetation burn or removal are well-known factors affecting landslides and avalanches. Lithology-dependent bedrock physicochemical-mechanical properties—especially brittle elastic and shear strength, and chemical weathering properties that affect rock strength, are also recognized controls on landsliding and avalanching, but are not commonly considered in detail in landslide susceptibility assessment. Lithology controls the formation of weakened, weathered bedrock; the formation and accumulation of soils; soil saturation-related properties of grain size distribution, porosity, and permeability; and soil creep related to soil wetting-drying and freeze-thaw. Lithology controls bedrock abrasion and glacial erosion and debris production rates, the formation of rough or smoothed bedrock surface by glaciation, fluvial, and freeze-thaw processes. Lithologic variability (e.g., bedding; fault and joint structure) affects contrasts in chemical weathering rates, porosity, and susceptibility to frost shattering and chemical weathering, hence formation of overhanging outcrops and weakened slip planes. The sudden failure of bedrock or sudden slip of ice on bedrock, and many other processes depend on rock lithology, microstructure (porosity and permeability), and macrostructure (bedding; faults). These properties are sometimes considered in gross terms for landslide susceptibility assessment, but in detailed applications to specific development projects, and in detailed mapping over

Joint Inversion of Geochemical Data and Geophysical Logs for Lithology Identification in CCSD Main Hole

Science.gov (United States)

Deng, Chengxiang; Pan, Heping; Luo, Miao

2017-12-01

The Chinese Continental Scientific Drilling (CCSD) main hole is located in the Sulu ultrahigh-pressure metamorphic (UHPM) belt, providing significant opportunities for studying the metamorphic strata structure, kinetics process and tectonic evolution. Lithology identification is the primary and crucial stage for above geoscientific researches. To release the burden of log analyst and improve the efficiency of lithology interpretation, many algorithms have been developed to automate the process of lithology prediction. While traditional statistical techniques, such as discriminant analysis and K-nearest neighbors classifier, are incompetent in extracting nonlinear features of metamorphic rocks from complex geophysical log data; artificial intelligence algorithms are capable of solving nonlinear problems, but most of the algorithms suffer from tuning parameters to be global optimum to establish model rather than local optimum, and also encounter challenges in making the balance between training accuracy and generalization ability. Optimization methods have been applied extensively in the inversion of reservoir parameters of sedimentary formations using well logs. However, it is difficult to obtain accurate solution from the logging response equations of optimization method because of the strong overlapping of nonstationary log signals when applied in metamorphic formations. As oxide contents of each kinds of metamorphic rocks are relatively less overlapping, this study explores an approach, set in a metamorphic formation model and using the Broyden Fletcher Goldfarb Shanno (BFGS) optimization algorithm to identify lithology from oxide data. We first incorporate 11 geophysical logs and lab-collected geochemical data of 47 core samples to construct oxide profile of CCSD main hole by using backwards stepwise multiple regression method, which eliminates irrelevant input logs step by step for higher statistical significance and accuracy. Then we establish oxide response

Lithologic features and Uranium possibilities of the granites of ...

African Journals Online (AJOL)

Preliminary lithologic and uranium investigation conducted in Pupule and environs to investigate further the area of uranium mineralisation in the neighbouring district revealed that the area is not attractive for further uranium search. Geologic field mapping shows that the area like most other parts of the region is underlain ...

Lithological Classification Using Sentinel-2A Data in the Shibanjing Ophiolite Complex in Inner Mongolia, China

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Wenyan Ge

2018-04-01

Full Text Available As a source of data continuity between Landsat and SPOT, Sentinel-2 is an Earth observation mission developed by the European Space Agency (ESA, which acquires 13 bands in the visible and near-infrared (VNIR to shortwave infrared (SWIR range. In this study, a Sentinel-2A imager was utilized to assess its ability to perform lithological classification in the Shibanjing ophiolite complex in Inner Mongolia, China. Five conventional machine learning methods, including artificial neural network (ANN, k-nearest neighbor (k-NN, maximum likelihood classification (MLC, random forest classifier (RFC, and support vector machine (SVM, were compared in order to find an optimal classifier for lithological mapping. The experiment revealed that the MLC method offered the highest overall accuracy. After that, Sentinel-2A image was compared with common multispectral data ASTER and Landsat-8 OLI (operational land imager for lithological mapping using the MLC method. The comparison results showed that the Sentinel-2A imagery yielded a classification accuracy of 74.5%, which was 2.5% and 5.08% higher than those of the ASTER and OLI imagery, respectively, indicating that Sentinel-2A imagery is adequate for lithological discrimination, due to its high spectral resolution in the VNIR to SWIR range. Moreover, different data combinations of Sentinel-2A + ASTER + DEM (digital elevation model and OLI + ASTER + DEM data were tested on lithological mapping using the MLC method. The best mapping result was obtained from Sentinel-2A + ASTER + DEM dataset, demonstrating that OLI can be replaced by Sentinel-2A, which, when combined with ASTER, can achieve sufficient bandpasses for lithological classification.

Lithological-morphological map of Italy: Instrument for environmental protection

International Nuclear Information System (INIS)

Noe', L.

1991-01-01

This paper describes the development by ENEA (Italian Commission for New Technologies, Energy and the Environment) of a map which identifies and coordinates the principal lithological and morphological features of Italy's environmental ecosystems. The map is intended especially for use in site characterization studies and environmental impacts assessments in construction projects involving hydroelectric power dams and geothermal power plants

A Comparison of Anorthositic Lunar Lithologies: Variation on the FAN Theme

Science.gov (United States)

Nyquist, L. E.; Shih, C-Y.; Yamaguchi, A.; Mittlefehldt, D. W.; Peng, Z. X.; Park, J.; Herzog, G. F.; Shirai, N.

2014-01-01

Certain anorthositic rocks that are rare in the returned lunar samples have been identified among lunar meteorites. The variety of anorthosites in the Apollo collection also is more varied than is widely recognized. James eta. identified three lithologies in a composite clast o ferroan anorthosite (FAN)-suite rocks in lunar breccia 64435. They further divided all FANs into four subgroups: anorthositic ferroan (AF), mafic magnesian (MM), mafic ferroan (MF), and anorthositic sodic (AS, absent in the 64435 clast). Here we report Sm-Nd isotopic studies of the lithologies present in the 64435 composite clast and compare the new data to our previous data for lunar anorthosites incuding lunar anorthositic meteorites. Mineralogy-petrography, in situ trace element studies, Sr-isotope studies, and Ar-Ar chronology are included, but only the Nd-isotopic studies are currently complete.

Investigating lithological and geophysical relationships with applications to geological uncertainty analysis using Multiple-Point Statistical methods

DEFF Research Database (Denmark)

Barfod, Adrian

The PhD thesis presents a new method for analyzing the relationship between resistivity and lithology, as well as a method for quantifying the hydrostratigraphic modeling uncertainty related to Multiple-Point Statistical (MPS) methods. Three-dimensional (3D) geological models are im...... is to improve analysis and research of the resistivity-lithology relationship and ensemble geological/hydrostratigraphic modeling. The groundwater mapping campaign in Denmark, beginning in the 1990’s, has resulted in the collection of large amounts of borehole and geophysical data. The data has been compiled...... in two publicly available databases, the JUPITER and GERDA databases, which contain borehole and geophysical data, respectively. The large amounts of available data provided a unique opportunity for studying the resistivity-lithology relationship. The method for analyzing the resistivity...

Lithological model of the South China crust based on integrated geophysical data

International Nuclear Information System (INIS)

Zhao, Bing; Bai, Zhiming; Xu, Tao; Zhang, Zhi; Badal, José

2013-01-01

The structure and petrology of the earth's crust is critical to understand the growth and evolution of the continents. In this paper, we present the crustal lithological model along the 400-km-long seismic profile between Lianxian, near Hunan Province, and Gangkou Island, near Guangzhou City, South China. This model is based on an integrated geophysical data set including P-wave velocity (V P ), S-wave velocity (V S ), V P /V S ratio, mass density (ρ) and Lamé impedances (ρλ, ρµ), which are compared to those determined by laboratory measurements on a variety of crustal rock samples. The Bouguer gravity anomaly together with the seismic velocity enables us to constrain density. The heat flow and thermal field allow us to carry out corrections for temperature. Pressure correction is based on depth. We directly compare the property parameters determined from the South China seismic data with laboratory measurements made at the same conditions of pressure and temperature. Inversion of the available data for rock lithology indicates that there are substantial differences in the crustal lithology of the Yangtze and Cathaysia blocks. While the average lithology of the upper crust in both blocks is mainly characterized by granite–granodiorite and biotite gneiss, the granite–granodiorite layer is much thicker beneath the Cathaysia block. The middle crust in these two domains is not entirely similar, being granite–granodiorite and granite gneiss as the best fit for the Yangtze block, and granite gneiss and biotite gneiss for the Cathaysia block. The lower crust is composed of biotite gneiss, paragranulite and amphibolite for the Yangtze block, whereas biotite gneiss, paragranulite, diorite, mica quartz schist, amphibolite, green schist facies basalt and hornblende provide the best fit for the Cathaysia block. The results demonstrate that to the east of the Chenzhou–Linwu fault (CLF) that is the southern segment of the Jiangshan–Shaoxing fault, the lithology

lithologic features and uranium possibilities of the granites of pupule

African Journals Online (AJOL)

Preliminary lithologic and uranium investigation conducted in Pupule and environs to investigate further the area of uranium mineralisation in the neighbouring district revealed that the area is not attractive for further uranium search. Geologic field mapping shows that the area like most other parts of the region is underlain ...

Lithology-dependent In Situ Stress in Heterogeneous Carbonate Reservoirs

Science.gov (United States)

Pham, C. N.; Chang, C.

2017-12-01

Characterization of in situ stress state for various geomechanical aspects in petroleum development may be particularly difficult in carbonate reservoirs in which rock properties are generally heterogeneous. We demonstrate that the variation of in situ stress in highly heterogeneous carbonate reservoirs is closely related to the heterogeneity in rock mechanical property. The carbonate reservoir studied consists of numerous sequential layers gently folded, exhibiting wide ranges of porosity (0.01 - 0.29) and Young's modulus (25 - 85 GPa) depending on lithology. Wellbore breakouts and drilling-induced tensile fractures (DITFs) observed in the image logs obtained from several wells indicate that the in situ state of stress orientation changes dramatically with depth and location. Even in a wellbore, the azimuth of the maximum horizontal stress changes by as much as 60° within a depth interval of 500 m. This dramatic change in stress orientation is inferred to be due to the contrast in elastic properties between different rock layers which are bent by folding in the reservoir. The horizontal principal stress magnitudes are constrained by back-calculating stress conditions necessary to induce the observed wellbore failures using breakout width and the presence of DITFs. The horizontal stresses vary widely, which cannot be represented by a constant stress gradient with depth. The horizontal principal stress gradient increases with Young's modulus of layer monotonically, indicating that a stiffer layer conveys a higher horizontal stress. This phenomenon can be simulated using a numerical modelling, in which the horizontal stress magnitudes depend on stiffness of individual layers although the applied far-field stress conditions are constant. The numerical results also suggest that the stress concentration at the wellbore wall is essentially higher in a stiffer layer, promoting the possibility of wellbore breakout formation. These results are in agreement with our

Experimental Investigations into the Effects of Lithology on Acoustic Emission

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Baozhu Tian

2015-11-01

Full Text Available In order to study how lithology affects acoustic emissions (AE, a series of tunnel rock burst simulation experiments, monitored by acoustic emission instruments, were conducted on granite, marble and basalt. By analyzing the characteristic parameters, this study found that AE events occur more frequently during the rock burst process on granite and basalt. Marble remains dormant until 75% of the loading time before the peak, at which point, cracks develop rapidly and AE events dramatically increase. During the rock burst process, the AE energy release demonstrates that low energy is released in the incubation phase and robust energy is released during the later phase. Before the rock burst occurs, increased in the heterogeneity index Cv values of the AE event are subject to lithology. The Cv values of granite and basalt have an increase of about 0.2-0.4, while marble shows an increase of 1.0-1.2. The heterogeneity index Cv value of an AE event is in line with the rock burst process.

Towards automatic lithological classification from remote sensing data using support vector machines

Science.gov (United States)

Yu, Le; Porwal, Alok; Holden, Eun-Jung; Dentith, Michael

2010-05-01

Remote sensing data can be effectively used as a mean to build geological knowledge for poorly mapped terrains. Spectral remote sensing data from space- and air-borne sensors have been widely used to geological mapping, especially in areas of high outcrop density in arid regions. However, spectral remote sensing information by itself cannot be efficiently used for a comprehensive lithological classification of an area due to (1) diagnostic spectral response of a rock within an image pixel is conditioned by several factors including the atmospheric effects, spectral and spatial resolution of the image, sub-pixel level heterogeneity in chemical and mineralogical composition of the rock, presence of soil and vegetation cover; (2) only surface information and is therefore highly sensitive to the noise due to weathering, soil cover, and vegetation. Consequently, for efficient lithological classification, spectral remote sensing data needs to be supplemented with other remote sensing datasets that provide geomorphological and subsurface geological information, such as digital topographic model (DEM) and aeromagnetic data. Each of the datasets contain significant information about geology that, in conjunction, can potentially be used for automated lithological classification using supervised machine learning algorithms. In this study, support vector machine (SVM), which is a kernel-based supervised learning method, was applied to automated lithological classification of a study area in northwestern India using remote sensing data, namely, ASTER, DEM and aeromagnetic data. Several digital image processing techniques were used to produce derivative datasets that contained enhanced information relevant to lithological discrimination. A series of SVMs (trained using k-folder cross-validation with grid search) were tested using various combinations of input datasets selected from among 50 datasets including the original 14 ASTER bands and 36 derivative datasets (including 14

Geostatistical analysis of the relationship between airborne electromagnetic data and borehole lithological data

DEFF Research Database (Denmark)

Barfod, Adrian; Møller, Ingelise; Christiansen, Anders Vest

2015-01-01

resistivity values, revealing different distribution functions for lithological categories. A very large and extensive dataset is available in Denmark through the national geophysical and borehole databases. These databases contain all geophysical and borehole data in Denmark and covers a large part of its......We present a large-scale study of the relationship between dense airborne SkyTEM resistivity data and sparse lithological borehole data. Airborne electromagnetic (AEM) data contains information about subsurface geology and hydrologic properties; however extracting this information is not trivial....... Today, geophysical data is used in combination with borehole data to create detailed geological models of the subsurface. The overall statistical relationship is, however, not widely known. The objective of this study is to develop a method for understanding the relationship between petrophysical...

Aeroradiospectrometry in the lithological mapping and environmental monitoring of Wadi Araba Area

International Nuclear Information System (INIS)

El-Sadek, Mohamed A.; Ammar, Ahmad A.; Sabry, Ahmad M.

2002-01-01

The aim of this airborne radiospectrometric study is to delineate, modify, and correct the regional lithology as well as to define and monitor the environmental background of Wadi Araba area, Northern Eastern, Egypt. The study uses the aerial radiospectrometric survey data and the regional geological map as the main sources of the information. The aeroradiospectrometric survey data have been statistically analyzed and correlated with the compiled geological map of the area under study. This analysis resulted in the delineation of several new interpreted radiometric lithologic (IRL) units. Corresponding statistical characteristics have been computed and established for each IRL unit in the investigated area. The various four statistical inference tests were applied to the total count (T.C.) radiometric characteristic statistics to determine whether or not a statistically significant difference exists between the computed statistics possessed by the different IRL units (normal distributions) in the studied area. The four tests include the Bartlett's, Analysis of Variance (ANOVA), Fisher's (F) and Students (t). From the results of statistical inference tests, only one group of IRL units from Rod El-Hamal Formation (RHF-2, RHF-3 and RHF-4) as well as only one group from Wadi Irkas Formation (WIF-2, WIF-5 and WIF-7) could be considered as belonging to one and same parent lithological population. Moreover, one pair from Wadi Irkas Formation (WIF-3 and WIF-8), as well as one group (QtS-4, QtS-7 and QtS-8) and three pairs (QtS-3 and QtS-5), (QtS-10 and QtS-17) and (QtS-12 and QtS-13) from Quaternary Sediments could be considered as belonging to one and the same parent lithological populations from the radioactivity point of view. The dose-rate map of the study area shows that the maximum dose-arte value originating from the terrestrial gamma-radiation reaches 0.36 mSv/y. This value is associated with the Rod El-Hamal Formation, which remains in the safe side and within the

Lithologic boundaries from gravity and magnetic anomalies over Proterozoic Dalma volcanics

Science.gov (United States)

Yadav, Pramod Kumar; Adhikari, P. K.; Srivastava, Shalivahan; Maurya, Ved P.; Tripathi, Anurag; Singh, Shailendra; Singh, Roshan K.; Bage, Ashish K.

2018-03-01

Dalma volcanics (DVs) has intruded the older Singhbhum Group of Metapelites. Despite DVs being rich in mineralisation, its boundaries are not clearly demarcated. Gravity and magnetic surveys have been attempted for mapping the boundaries in DVs. These surveys were made in the northern fringe of the DVs over an area of ˜ 0.70 km2 along 13 parallel lines at 50 m spacing. The data was acquired at ˜ 25 m spacing. The surveys were taken for determination of lithological boundaries, depths and nature of causative source using Euler depth solutions and radially averaged power spectrum (RAPS). Residual anomaly maps of gravity and magnetic intensity show the same trend as that of Bouguer gravity anomaly and total magnetic intensity anomaly map indicating towards shallow sources. The magnetic map in general follows the same pattern as that of gravity anomaly maps. The map shows coincident high gravity and magnetic anomalies. These anomalies together with resistivity signatures confirm that the northern fringe of DVs hosts volcanogenic massive sulphide settings. The Euler depth solution delineated the lateral boundaries and nature of the source. It seems that the source is of spherical nature lying within a depth range of 25-40 m. The obtained lithological (vertical) units from RAPS are between Lower DVs, Upper DVs and Singhbhum Group Metapelites at depths of ˜ 15, ˜ 25 and ˜ 40 m, respectively. The metallogeny is associated with the Upper DVs and the corresponding delineated lithological (vertical) unit is indicative of the top of the ore body. Good agreement is observed with the geological succession from the drilling data and resistivity data. The findings suggest that the northern fringe of DVs could be a preferred target for drilling.

Classification of lithological units based on geophysical borehole logging - data from the Stripa mine

International Nuclear Information System (INIS)

Triumf, C.A.

1992-06-01

At the Crosshole site, located at the 360 m level in the Stripa mine, six boreholes F1-F6 have been drilled in a fanlike fashion. To achieve further knowledge of the geological conditions in the rock volumes outside the major tectonized zones, a classification of the pseudo-lithology has been carried out using data from boreholes F3-F6. The analysis has been supported by determination of density and magnetic susceptibility on core samples from boreholes F1-F5. This study demonstrates that the bulk of the tectonically less disturbed rock, forming the matrix in a network of dominant tectonical features, can be considered as homogeneous according to the silicate density. Three volumes with deviating lithology have however been identified in more than one borehole. Furthermore narrow sections are encountered, showing mineralogical, and probably also, micro-structural deviations from the normal granite. These narrow sections are irregularly spread along the boreholes. Their irregular distribution and narrowness, prevents correlation between boreholes. The result of the lithology identification is displayed using a modified Briggs cube. The method used in this project is applicable in many stages of an investigation programme where different disciplines are co-operating and partly complex information must be passed between individuals. (au)

Performance evaluation of groundwater model hydrostratigraphy from airborne electromagnetic data and lithological borehole logs

DEFF Research Database (Denmark)

Marker, Pernille Aabye; Foged, N.; He, X.

2015-01-01

resistivity and clay fraction are classified into hydrostratigraphic zones using k-means clustering. Hydraulic conductivity values of the zones are estimated by hydrological calibration using hydraulic head and stream discharge observations. The method is applied to a Danish case study. Benchmarking......Large-scale hydrological models are important decision support tools in water resources management. The largest source of uncertainty in such models is the hydrostratigraphic model. Geometry and configuration of hydrogeological units are often poorly determined from hydrogeological data alone. Due...... present a novel method to automatically integrate large AEM data sets and lithological information into large-scale hydrological models. Clay-fraction maps are produced by translating geophysical resistivity into clay-fraction values using lithological borehole information. Voxel models of electrical...

Lithologic Effects on Landscape Response to Base Level Changes: A Modeling Study in the Context of the Eastern Jura Mountains, Switzerland

Science.gov (United States)

Yanites, Brian J.; Becker, Jens K.; Madritsch, Herfried; Schnellmann, Michael; Ehlers, Todd A.

2017-11-01

Landscape evolution is a product of the forces that drive geomorphic processes (e.g., tectonics and climate) and the resistance to those processes. The underlying lithology and structural setting in many landscapes set the resistance to erosion. This study uses a modified version of the Channel-Hillslope Integrated Landscape Development (CHILD) landscape evolution model to determine the effect of a spatially and temporally changing erodibility in a terrain with a complex base level history. Specifically, our focus is to quantify how the effects of variable lithology influence transient base level signals. We set up a series of numerical landscape evolution models with increasing levels of complexity based on the lithologic variability and base level history of the Jura Mountains of northern Switzerland. The models are consistent with lithology (and therewith erodibility) playing an important role in the transient evolution of the landscape. The results show that the erosion rate history at a location depends on the rock uplift and base level history, the range of erodibilities of the different lithologies, and the history of the surface geology downstream from the analyzed location. Near the model boundary, the history of erosion is dominated by the base level history. The transient wave of incision, however, is quite variable in the different model runs and depends on the geometric structure of lithology used. It is thus important to constrain the spatiotemporal erodibility patterns downstream of any given point of interest to understand the evolution of a landscape subject to variable base level in a quantitative framework.

Shear weakening for different lithologies observed at different saturation stages

Science.gov (United States)

Diethart-Jauk, Elisabeth; Gegenhuber, Nina

2018-01-01

For this study, samples from different lithologies ("Leitha"-limestone, "Dachstein"-limestone, "Haupt"-dolomite, "Bunt"-sandstone, Grey Berea sandstone, granite, quartzite and basalt) were selected. Samples were dried at 70 °C, respectively 105 °C and were saturated with brine. Mass, porosity, permeability, compressional and shear wave velocity were determined from dry and brine saturated samples at laboratory conditions, based on an individual measurement program. Shear modulus was calculated to find out, if shear weakening exists for the dataset. Shear weakening means that shear modulus of dry samples is higher than of saturated samples, but it is assumed that shear modulus is unaffected by saturation. "Dachstein"-limestone and basalt show shear weakening, quartzite samples show both weakening and hardening. Granite samples are affected by temperature, after drying with 105 °C no change can be observed anymore. "Bunt"-sandstone samples show a change in the shear modulus in a small extent, although they may contain clay minerals. The other lithologies show no effect. Explanations for carbonate samples can be the complicated pore structure, for basalt it could be that weathering creates clay minerals which are known as causes for a change of the shear modulus. Fluid viscosity can also be an important factor.

Characterization of major lithologic units underlying the lower American River using water-borne continuous resistivity profiling, Sacramento, California, June 2008

Science.gov (United States)

Ball, Lyndsay B.; Teeple, Andrew

2013-01-01

The levee system of the lower American River in Sacramento, California, is situated above a mixed lithology of alluvial deposits that range from clay to gravel. In addition, sand deposits related to hydraulic mining activities underlie the floodplain and are preferentially prone to scour during high-flow events. In contrast, sections of the American River channel have been observed to be scour resistant. In this study, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, explores the resistivity structure of the American River channel to characterize the extent and thickness of lithologic units that may impact the scour potential of the area. Likely lithologic structures are interpreted, but these interpretations are non-unique and cannot be directly related to scour potential. Additional geotechnical data would provide insightful data on the scour potential of certain lithologic units. Additional interpretation of the resistivity data with respect to these results may improve interpretations of lithology and scour potential throughout the American River channel and floodplain. Resistivity data were collected in three profiles along the American River using a water-borne continuous resistivity profiling technique. After processing and modeling these data, inverted resistivity profiles were used to make interpretations about the extent and thickness of possible lithologic units. In general, an intermittent high-resistivity layer likely indicative of sand or gravel deposits extends to a depth of around 30 feet (9 meters) and is underlain by a consistent low-resistivity layer that likely indicates a high-clay content unit that extends below the depth of investigation (60 feet or 18 meters). Immediately upstream of the Watt Avenue Bridge, the high-resistivity layer is absent, and the low-resistivity layer extends to the surface where a scour-resistant layer has been previously observed in the river bed.

Evaluating the effect of lithology on porosity development in ridgetops in the Appalachian Piedmont

Science.gov (United States)

Marcon, V.; Gu, X.; Fisher, B.; Brantley, S. L.

2016-12-01

Together, chemical and physical processes transform fresh bedrock into friable weathered material. Even in systems where lithology, tectonic history, and climatic history are all known, it is challenging to predict the depth of weathering because the mechanisms that control the rate of regolith formation are not understood. In the Appalachian Piedmont, where rates of regolith formation and erosion are thought to be in a rough steady state, the depth of weathering varies with lithology. The Piedmont provides a controlled natural environment to isolate the effects of lithology on weathering processes so we can start to understand the mechanisms that initiate and drive weathering. Weathering is deepest over feldspathic rocks (schist/granite) with regolith 20-30m thick and thinnest over mafic and ultramafic rocks (diabase/serpentinite) with regolith serpentinization reactions and lost from collapse during weathering. Serpentinite consists of easily weathered hydrous minerals with little quartz. Comparatively, rocks with more quartz (e.g. schist) have a supportive skeleton as the rock weathers. This quartz skeleton could prevent the collapse of pores and result in isovolumetric weathering. Non-isovolumetric weathering limits infiltration of reactive fluids deeper into the rock, minimizing regolith formation in serpentinite due to its lack of a quartz skeleton. Given this, fracture toughness may be an important parameter to consider in terms of predicting regolith thickness.

An analysis of the lithology to resistivity relationships using airborne EM and boreholes

DEFF Research Database (Denmark)

Barfod, Adrian A.S.; Christiansen, Anders Vest; Møller, Ingelise

2014-01-01

We present a study of the relationship between dense airborne skyTEM resistivity data and sparse lithological borehole data. Understanding the resistivity structure of the subsurface is of great importance to hydrogeological surveys and to ensure a high standard for groundwater quality. Borehole ...

Summary of lithologic logging of new and existing boreholes at Yucca Mountain, Nevada, March 1994 to June 1994

International Nuclear Information System (INIS)

Geslin, J.K.; Moyer, T.C.

1995-01-01

This report summarizes lithologic logging of core from boreholes at Yucca Mountain, Nevada, conducted from March 1994 to June 1994. Units encountered during logging include Quaternary-Tertiary alluvium and colluvium, Tertiary Rainier Mesa Tuff, all units in the Tertiary Paintbrush Group, and Tertiary Calico Hills Formation. Logging results are presented in a table of contact depths for core from unsaturated zone neutron (UZN) boreholes and graphic lithologic logs for core from north ramp geology (NRG) boreholes

Determination of Soft Lithology Causes The Land Subsidence in Coastal Semarang City by Resistivity Methods

Science.gov (United States)

Widada, Sugeng; Saputra, Sidhi; Hariadi

2018-02-01

Semarang City is located in the northern coastal plain of Java which is geologically composed of alluvial deposits. The process of the sediment diagenesis has caused a land subsidence. On the other hand, the development of the industrial, service, education and housing sectors has increased the number of building significantly. The number of building makes the pressure of land surface increased, and finally, this also increased the rate of land subsidence. The drilling data indicates that not all layers of lithology are soft layers supporting the land subsidence. However, vertical distribution of the soft layer is still unclear. This study used Resistivity method to map out the soft zone layers of lithology. Schlumberger electrode configuration with sounding system method was selected to find a good vertical resolution and maximum depth. The results showed that the lithology layer with resistivity less than 3 ohm is a layer of clay and sandy clay that has the low bearing capacity so easily compressed by pressure load. A high land subsidence is happening in the thick soft layer. The thickness of that layer is smaller toward the direction of avoiding the beach. The improvement of the bearing capacity of this layer is expected to be a solution to the problem of land subsidence.

Lithologically inherited variation in Pb isotope ratios in sedimentary soils in The Netherlands

NARCIS (Netherlands)

Walraven, N.; Gaans, P.F.M. van; Veer, G. van der; Os, B.J.H. van; Klaver, G.T.; Vriend, S.P.; Middelburg, J.J.; Davies, G.R.

2013-01-01

Knowledge on the lithologically inherited variation in present day Pb isotope ratios in soils is remarkably limited. Such information is essential to determine the anthropogenic Pb fraction and anthropogenic Pb sources in Pb-polluted soils. This study presents results of a survey of subsoil samples

Simulating reservoir lithologies by an actively conditioned Markov chain model

Science.gov (United States)

Feng, Runhai; Luthi, Stefan M.; Gisolf, Dries

2018-06-01

The coupled Markov chain model can be used to simulate reservoir lithologies between wells, by conditioning them on the observed data in the cored wells. However, with this method, only the state at the same depth as the current cell is going to be used for conditioning, which may be a problem if the geological layers are dipping. This will cause the simulated lithological layers to be broken or to become discontinuous across the reservoir. In order to address this problem, an actively conditioned process is proposed here, in which a tolerance angle is predefined. The states contained in the region constrained by the tolerance angle will be employed for conditioning in the horizontal chain first, after which a coupling concept with the vertical chain is implemented. In order to use the same horizontal transition matrix for different future states, the tolerance angle has to be small. This allows the method to work in reservoirs without complex structures caused by depositional processes or tectonic deformations. Directional artefacts in the modeling process are avoided through a careful choice of the simulation path. The tolerance angle and dipping direction of the strata can be obtained from a correlation between wells, or from seismic data, which are available in most hydrocarbon reservoirs, either by interpretation or by inversion that can also assist the construction of a horizontal probability matrix.

Structural and Lithological Controls upon Fluid Migration within the Chalk and Upper Greensand Aquifers in the Chilterns and Lambourn Downs

OpenAIRE

Thompson, Sally

2002-01-01

The influence of lithological heterogeneities, structural discontinuities and discontinuity surface mineralisation upon groundwater migration within the Chalk and the Upper Greensand of southern England has been investigated. Lithological heterogeneities in the Chalk succession include marl seams, hardgrounds, tabular flints and nodular flints. Each of these heterogeneities has a lower intrinsic porosity and permeability than in the calcite rich chalk. The influence that each of these ...

Systematic Lithologic Calibration of Neogene Mass-Transport Deposits Seismic Character in Mississippi Canyon of the Northern Gulf of Mexico, USA.

Science.gov (United States)

Gutierrez, M. A.; Snedden, J.

2017-12-01

Few publications have attempted detailed lithologic calibration of Mass Transport Deposits, usually as a byproduct of mud log descriptions. While the principal motivation for further understanding these slope failure deposits are driven by the economics of deep-water hydrocarbon exploration, the geohazard-related risks of storm-wave loading, and the shallow gas, also provide a driving concern for these deposits. Such risks can be mitigated and prevented by in depth analysis of slope stability and failure. The Mississippi Canyon of the Northern Gulf of Mexico is one of the few basins to contain enough available density of seismic and well data to provide a well-constrained lithologic characterization throughout a MTD-rich continental margin. The proposed hypothesis evaluates: 1) the differences between attached and detached MTDs in the Neogene Northern Gulf of Mexico through seismic characterization and well log analysis, 2) variations of MTD dimensions and map geometries in relation to depositional age throughout the northeastern and northcentral Gulf of Mexico, and 3) the differentiation between sand-prone and shale-prone MTD's in relation to associated depositional mechanisms. This study will attempt lithologic calibration of MTDs in Pleistocene -Miocene strata of the study area through integration of seismic observations (focused in supra-salt basins, which have the highest seismic data quality) and lithologic related information extracted from logs, mud logs (cuttings), and available core data to further constrain the distribution of MTD types, lithology, and geometries. Initial interpretations reflect a variance of seismic character responses to the presence of sandstone and shale (constrained by wells) throughout different regions and salt tectonic domains of the MTD geobodies. Further analysis will relate different seismic facies throughout MTDs to improve the understanding of seismic character and related lithologic facies throughout the deposits, in

Reactivity of Ordinary Portland Cement (OPC) grout and various lithologies from the Harwell research site

International Nuclear Information System (INIS)

Milodowski, A.E.; George, I.A.; Bloodworth, A.J.; Robins, N.S.

1985-08-01

Ordinary Portland Cement (OPC) has been used in the completion of boreholes on the Harwell Research Site, AERE, Oxfordshire. The purpose of this study was to examine the effect of OPC and the alkaline pore fluids generated during its setting on the various lithological types encountered in the boreholes. To facilitate this, samples of core representing the various rock types were selected and cement-rock composites were prepared from these in the laboratory to simulate the borehole cements. After a curing period of 15 months the cores and associated cement plugs were examined for any signs of reactivity or bonding. The best cement-rock bonding was shown by naturally well-cemented sandstone and limestone lithologies. Although no significant chemical reaction was seen to have occurred between OPC and rock, the OPC appears able to bind onto the rock surface because of the rigidity of the rock surface. Therefore, the best cement rock bonding and seal with OPC may be expected in the limestones of the Great Oolite Group, Inferior Oolite Group and parts of the Corallian Beds. Because of the reactivity of OPC towards certain lithologies a better borehole seal in such a sedimentary sequence might be achieved using a bentonite backfill in those parts of the sequence which either react with or bond only weakly to OPC. (author)

The impact of mixing lithologies in clast shape measurements on its discriminatory power - a case study from a temperate Alpine glacier

Science.gov (United States)

Lukas, S.; Coray, S.; Graf, A.; Schlüchter, C.

2009-04-01

Clast shape measurements have become a standard tool in the reconstruction of transport histories in a variety of depositional settings (Demir et al., 2009). In glacial environments, the combined use of clast form and roundness has become an established tool in the past 15 years or so, and environments where this tool has been used range from temperate and polythermal to cold-based glaciers. In addition, the method has been transferred to palaeo-environments where the knowledge gained in aforementioned studies has taken the degree of accuracy in sedimentological investigations to a higher level (cf. Lukas et al., 2009, and references therein). All of these studies use the approach originally advocated by Benn and Ballantyne (1994), but perhaps the most notable difference is that some researchers mix different lithologies within their samples of 50 clasts. However, the role of lithology on clast shape in a glacial environment has never been systematically analysed, except for one pilot study (Bennett et al., 1997). Likewise, some previous studies have highlighted the problem of distinguishing between fluvial and subglacially-transported clasts using co-variance plots, and thus, more work is needed in both these respects. We here present a set of clast shape data gathered from the foreland and surrounding slopes of temperate Findelengletscher, Switzerland, to (a) test the versatility of clast shape in distinguishing of populations of clasts transported along different paths and (b) assess the role of lithology on the discriminatory potential of the method, most notably using co-variance plots. The main result of this pilot study is that the sampled lithology has a marked effect on clast shape results within the same control group. This is manifest in an overlap of envelopes in both RA- or RWR-C40-covariance plots. If kept separate, all three lithologies display separate control envelopes, in this case in RWR-C40-co-variance plots, thus keeping their discriminatory

Itataia's phosphorous-uraniferous deposit - Alteration and argilization influence in physical processing of the mineralized lithologies

International Nuclear Information System (INIS)

Rosa, C.V.

1986-01-01

This study was developed by NUCLEBRAS, firstly defining the quality and quantity of the Itataia ore body untill the 480 m level of the future pit, considering the lithological types, the P 2 O 5 and U 3 O 8 contents and the alteration and argillization of the rocks. The following step was to establish the physicochemical character of the mineralized lithologies according to the phases of alteration/argillization. Finally it was compared the results of these two stages with the results of the pilot treatment, related to the gangue in the phosphoric acid concentrate. The method showed the difficulties in each host rock, differently altered/argillized for future process and allowed to the identification of seven types of material to supply the Itataia pilot plant. (author) [pt

Evolved-Lithology Clasts in Lunar Breccias: Relating Petrogenetic Diversity to Measured Water Content

Science.gov (United States)

Christoffersen, R.; Simon, J. J.; Ross, D. K.

2017-01-01

Studies of the inventory and distribution of water in lunar rocks have recently begun to focus on alkali suite samples as possible water repositories, particularly the most highly evolved granitoid lithologies. Although H analyses of feldspars in these rocks have so far pointed to 'low' (less than 20 ppm) H2O contents, there is sufficient variability in the dataset (e.g., 2-20 ppm) to warrant consideration of the petrogenetic factors that may have caused some granitoid-to-intermediate rocks to be dryer or wetter than others. Given that all examples of these rocks occur as clasts in complex impact breccias, the role of impact and other factors in altering water contents established by primary igneous processes becomes a major factor. We are supporting our ongoing SIMS studies of water in evolved lunar lithologies with systematic SEM and EPMA observations. Here we report a synthesis of the observations as part of developing discriminating factors for reconstructing the thermal, crystallization and shock history of these samples as compared with their water contents.

An automated method to build groundwater model hydrostratigraphy from airborne electromagnetic data and lithological borehole logs

DEFF Research Database (Denmark)

Marker, Pernille Aabye; Foged, N.; He, X.

2015-01-01

of electrical resistivity and clay fraction are classified into hydrostratigraphic zones using k-means clustering. Hydraulic conductivity values of the zones are estimated by hydrological calibration using hydraulic head and stream discharge observations. The method is applied to a Danish case study......Large-scale integrated hydrological models are important decision support tools in water resources management. The largest source of uncertainty in such models is the hydrostratigraphic model. Geometry and configuration of hydrogeological units are often poorly determined from hydrogeological data......-scale groundwater models. We present a novel method to automatically integrate large AEM data-sets and lithological information into large-scale hydrological models. Clay-fraction maps are produced by translating geophysical resistivity into clay-fraction values using lithological borehole information. Voxel models...

The Chicxulub event - sulfur-bearing minerals and lithologies

Science.gov (United States)

Strauss, H.; Deutsch, A.

2003-04-01

Evaporates form a major target lithology at the Chicxulub impact site. One of the postulated effects of the impact event at the Cretaceous/Tertiary boundary is the impact-induced dissociation of anhydrite to form sulfur-oxides and a solid residue; large isotope fractionation effects in sulfur should accompany this process. We have analyzed the sulfur isotope composition of (i) annealed anhydrite clasts in impact melt breccias of PEMEX core Yucatan-6 N 19, (ii) unshocked anhydrite from the CSDP well Yaxcopoil-1, which belong to the megabreccia below the suevite layer (YAX-1 1369, and 1376 m depth), and (iii) sulfide grains of hydrothermal origin in a finest-grained breccia, which transects a large limestone block of this megabreccia at a depth of 1369 m. Samples of groups (i) and (ii) yielded δ34S values between 18.0 and 19.8 ppm CDT (unweighted mean is 18.3 ppm, n=7), with one slightly lower value of 15.3 ppm for an anhydrite clast in Y-6 N19/Part 6. These data are in agreement with the δ34S value for the Late Cretaceous seawater (Strauss 1999). The δ34S obviously remained unchanged despite the fact that textural features indicate a severe annealing of the clasts in the impact melt. Sulfides of group (iii) show δ34S values around 41 ppm CDT (n=7), which are quite unusual values if these minerals are of non-biogenic origin. In contrast, δ34S for the yellow glass from the K/T boundary at Haiti range from 1.5 to 13.2 ppm (Chaussidon et al. 1996). Using this preliminary evidence, we conclude that only distant ejecta lithologies, and probably secondary material inside the crater, may display impact-related fractionation of sulfur isotopes. This observation is consistent with petrologic data, modeling results as well as of shock recovery and annealing experiments: anhydrite obviously is quite resistant to shock-related dissociation.

Lithological and mineralogical changes observed in a core from the western Bay of Bengal

Digital Repository Service at National Institute of Oceanography (India)

Reddy, N.P.C.; Rao, K.M.; Putra, S.V.S; Rao, Ch.M.

Lithological and mineralogical studies were carried out on sediments from a 650 cm long core from the north western Bay of Bengal at a depth of 2700 m. These studies demarcate a boundary at 380 cm designated as unit 1 from 0-380 cm and unit 2 from...

LP-HT anatectic processes and lithological heterogeneity in the Mindelo Migmatite Complex (NW Portugal

Directory of Open Access Journals (Sweden)

Areias, M.

2014-12-01

Full Text Available The Mindelo Migmatitic Complex crops out in the coastal zone north of Porto (Portugal and consists of a set of migmatitic and granitic lithologies. Field relationships, petrography, geochemistry and isotopic signature of the various lithologies allow inferring the sequence of anatectic processes that resulted in their characteristic lithological heterogeneity. The metasedimentary sequences (Schist-Greywacke Complex show chemical composition and isotopic signature identical to the metatexites. So is suggested to be the protolith of Mindelo Migmatite Complex lithologies. The melting has occurred in several structural levels and thus at different pressure and temperature conditions, resulting in rocks with specific characteristics. In shallow levels ( 3. The several pulses of different fluids that affected the Mindelo Migmatitic Complex probably are related to the emplacement of the syn and late- D3 variscan granites. The Mindelo Migmatite Complex represents an example of migmatites formed in low pressure conditions and illustrates some of the reactions involving melting in high grade pelitic rocks and subsequent mineral alterations due to infiltration of late different fluids.El Complejo Migmatítico de Mindelo aflora en la zona costera de Portugal al norte de Oporto y se compone de un conjunto de litologías migmatíticas y graníticas. Las relaciones de campo, petrografía, geoquímica y las características isotópicas de las diferentes litologías permiten inferir la secuencia de procesos anatécticos que dio lugar a su típica heterogeneidad litológica. La composición química e isotópica de la secuencia metasedimentaria del Complejo Esquisto-Grauváquico es idéntica a la de las metatexitas, lo que sugiere que sea el protolito de las litologías del Complejo de Mindelo. La fusión se ha producido en varios niveles estructurales y por lo tanto en diferentes condiciones de presión y temperatura, dando lugar a rocas con caracter

BILLIARDS: Baseline Instrumented Lithology Lander, Inspector and Asteroid Redirection Demonstration System

Science.gov (United States)

Marcus, Matthew; Sloane, Joshua; Ortiz, Oliver; Barbee, Brent

2015-01-01

BILLIARDS Baseline Instrumented Lithology Lander, Inspector, and Asteroid Redirection Demonstration System Proposed demonstration mission for Billiard-Ball concept Select asteroid pair with natural close approach to minimize cost and complexity Primary Objectives Rendezvous with a small (10m), near Earth (alpha) asteroid Maneuver the alpha asteroid to a collision with a 100m (beta) asteroid Produce a detectable deflection or disruption of the beta asteroid Secondary objectives Contribute knowledge of asteroid composition and characteristics Contribute knowledge of small-body formation Opportunity for international collaboration

Comparison of Different Machine Learning Algorithms for Lithological Mapping Using Remote Sensing Data and Morphological Features: A Case Study in Kurdistan Region, NE Iraq

Science.gov (United States)

Othman, Arsalan; Gloaguen, Richard

2015-04-01

Topographic effects and complex vegetation cover hinder lithology classification in mountain regions based not only in field, but also in reflectance remote sensing data. The area of interest "Bardi-Zard" is located in the NE of Iraq. It is part of the Zagros orogenic belt, where seven lithological units outcrop and is known for its chromite deposit. The aim of this study is to compare three machine learning algorithms (MLAs): Maximum Likelihood (ML), Support Vector Machines (SVM), and Random Forest (RF) in the context of a supervised lithology classification task using Advanced Space-borne Thermal Emission and Reflection radiometer (ASTER) satellite, its derived, spatial information (spatial coordinates) and geomorphic data. We emphasize the enhancement in remote sensing lithological mapping accuracy that arises from the integration of geomorphic features and spatial information (spatial coordinates) in classifications. This study identifies that RF is better than ML and SVM algorithms in almost the sixteen combination datasets, which were tested. The overall accuracy of the best dataset combination with the RF map for the all seven classes reach ~80% and the producer and user's accuracies are ~73.91% and 76.09% respectively while the kappa coefficient is ~0.76. TPI is more effective with SVM algorithm than an RF algorithm. This paper demonstrates that adding geomorphic indices such as TPI and spatial information in the dataset increases the lithological classification accuracy.

Catalog of borehole lithologic logs from the 600 Area, Hanford Site

International Nuclear Information System (INIS)

Fecht, K.R.; Lillie, J.T.

1982-03-01

Rockwell Hanford Operations (Rockwell) geoscientists are studying the Hanford Site subsurface environment to assure safe management operations, disposal, and storage of radioactive waste. As part of this effort, geoscientists have collected geotechnical data from about 3000 boreholes drilled on the Hanford Site since the early 1900s. These boreholes have been used for subsurface geologic, hydrologic, and engineering investigation, water supply, ground-water monitoring, and natural gas production. This report is a catalog of all obtainable (about 800) lithologic logs from boreholes in a portion of the Hanford Site known as the 600 Area

INFLUENCE OF SEDIMENT SUPPLY, LITHOLOGY, AND WOOD DEBRIS ON THE DISTRIBUTION OF BEDROCK AND ALLUVIAL CHANNELS

Science.gov (United States)

Field surveys in the Willapa River basin, Washington State, indicate that the drainage area?channel slope threshold describing the distribution of bedrock and alluvial channels is influenced by the underlying lithology and that local variations in sediment supply can overwhelm ba...

Lithological history and ductile deformation: the lessons for long-term stability of large-scales structures in the olkiluoto

International Nuclear Information System (INIS)

Wikstrom, L.; Aaltonen, I.; Mattila, J.

2009-01-01

The Olkiluoto site has been chosen as a repository site for the high-level nuclear waste in 2001. Investigations in the site have been ongoing since 1987. The basic idea in the crystalline nuclear waste site still is that the solid repository block surrounded by deformation zones can host a safe repository. It is impossible to say that neither the major ductile nor large-scale brittle deformation zones are stable, but it is possible to say that the tectonic processes have been active in a stable way for billions of years by reactivating the old features time after time and there are no signs of new large features formed in the vicinity of the site during the present time including post-glacial period. Understanding the geological history, especially the ductile deformation and over thrusting, begins from the understanding of the lithological features, mainly rock types, in the island. Vice versa, the occurrence and location of the lithological features are interpreted according to ductile deformation. In addition, you cannot study only present brittle deformation but you need to understand also older ductile and lithological features to be able to understand why these brittle features are where they are and to be able to predict them. (authors)

Investigation of the structure and lithology of bedrock concealed by basin fill, using ground-based magnetic-field-profile data acquired in the San Rafael Basin, southeastern Arizona

Science.gov (United States)

Bultman, Mark W.

2013-01-01

Data on the Earth’s total-intensity magnetic field acquired near ground level and at measurement intervals as small as 1 m include information on the spatial distribution of nearsurface magnetic dipoles that in many cases are unique to a specific lithology. Such spatial information is expressed in the texture (physical appearance or characteristics) of the data at scales of hundreds of meters to kilometers. These magnetic textures are characterized by several descriptive statistics, their power spectrum, and their multifractal spectrum. On the basis of a graphical comparison and textural characterization, ground-based magnetic-field profile data can be used to estimate bedrock lithology concealed by as much as 100 m of basin fill in some cases, information that is especially important in assessing and exploring for concealed mineral deposits. I demonstrate that multifractal spectra of ground-based magnetic-field-profile data can be used to differentiate exposed lithologies and that the shape and position of the multifractal spectrum of the ground-based magnetic-field-profile of concealed lithologies can be matched to the upward-continued multifractal spectrum of an exposed lithology to help distinguish the concealed lithology. In addition, ground-based magnetic-field-profile data also detect minute differences in the magnetic susceptibility of rocks over small horizontal and vertical distances and so can be used for precise modeling of bedrock geometry and structure, even when that bedrock is concealed by 100 m or more of nonmagnetic basin fill. Such data contain valuable geologic information on the bedrock concealed by basin fill that may not be so visible in aeromagnetic data, including areas of hydrothermal alteration, faults, and other bedrock structures. Interpretation of these data in the San Rafael Basin, southeastern Arizona, has yielded results for estimating concealed lithologies, concealed structural geology, and a concealed potential mineral

Lithology, hydrologic characteristics, and water quality of the Arkansas River Valley alluvial aquifer in the vicinity of Van Buren, Arkansas

Science.gov (United States)

Kresse, Timothy M.; Westerman, Drew A.; Hart, Rheannon M.

2015-01-01

A study to assess the potential of the Arkansas River Valley alluvial aquifer in the vicinity of Van Buren, Arkansas, as a viable source of public-supply water was conducted by the U.S. Geological Survey in cooperation with the Little Rock, District, U.S. Army Corps of Engineers. An important study component was to identify possible changes in hydrologic conditions following installation of James W. Trimble Lock and Dam 13 (December 1969) on the Arkansas River near the study area. Data were gathered for the study in regard to the lithology, hydrologic characteristics, and water quality of the aquifer. Lithologic information was obtained from drillers’ logs of wells drilled from 1957 through 1959. Water-quality samples were collected from 10 irrigation wells and analyzed for inorganic constituents and pesticides. To evaluate the potential viability of the alluvial aquifer in the Van Buren area, these data were compared to similar stratigraphic, lithologic, and groundwater-quality data from the Arkansas River Valley alluvial aquifer at Dardanelle, Ark., where the aquifer provides a proven, productive, sole-source of public-supply water.

Origin of marls from the Polish Outer Carpathians: lithological and sedimentological aspects

Science.gov (United States)

Górniak, Katarzyna

2012-10-01

Outcrops of marls, occurring within the sandstone-shaly flysch deposits of the Polish part of Outer Carpathians, considered to be locus typicus of these rocks, were described, measured and sampled. Lithologic features of marls, representing 15 complexes of different age and occurring in 15 complexes of various tectonic units, are presented (Fig. 1, 2). The present studies were concerning Jurassic marls from the Silesian Unit (Goleszów Marls), Upper Cretaceous marls from the Skole and Sub-Silesian Units (Siliceous-Fucoid and Węgierka Marls and Węglowka, Frydek, Jasienica and Zegocina Marls respectively), and Eocene-Oligocene marls from the Magura, Fore-Magura and Skole Units (Łącko, Zembrzyce, Budzów, Leluchów and Niwa, as well as Grybów and Sub-Cergowa and Dynów Marls respectively). The former opinions on lithology, age, formal subdivision, sedimentation conditions and genesis of these rocks are discussed (Table 1, 2; Fig. 1). Detailed description of the above mentioned marl-bearing complexes are presented and for each of them the typical lithological features are determined (Tables 3 - 20). The results of profiling are presented against the background of geological studies of the Carpathian marls. The results of lithologic studies are compared to form a classification scheme and are used as the basis of distinguishing genetic types of marls. Moreover, the interpretation of the conditions of sedimentation of these rocks is presented. According to the present author’s studies, in the outcrops of marls considered to be locus typicus of the above mentioned rocks, there are both monolithic and polylithic complexes exposed. The polylithic complexes contain apart from marls intercalations of arenaceous-shaly flysch (Table 19). Event sedimentation of marly facies, appearing at different times and in various parts of the Carpathian basin is the result of periodically repeating conditions favouring the sedimentation of marls. Carpathian marls seem to be

Lithological classification assisted by the joint inversion of electrical and seismic data at a control site in northeast Mexico

Science.gov (United States)

Infante, Victor; Gallardo, Luis A.; Montalvo-Arrieta, Juan C.; Navarro de León, Ignacio

2010-02-01

In this paper, evidence is presented that the combination of geospectral images and geophysical signatures (resistivity-velocity cross-plots) is a good tool to provide a natural visualization of the distribution and variations of lithological features in a test site. This was confirmed by the correlation between the electrical resistivity and seismic velocity values obtained after cross-gradient joint inversion at two profiles and geotechnical information provided by shallow boreholes in a site located in the Earth Sciences School grounds in Linares, Northeastern Mexico. The results obtained from this study show how the cross-gradient joint inversion facilitates the analysis of hydrological estimates and assists in lithological classification of subsurface materials.

Contingency table analysis of pebble lithology and roundness: A case study of Huangshui River, China and comparison to rivers in the Rocky Mountains, USA

Science.gov (United States)

Miao, X.; Lindsey, D.A.; Lai, Z.; Liu, Xiuying

2010-01-01

Contingency table analysis of pebble lithology and roundness is an effective way to identify the source terrane of a drainage basin and to distinguish changes in basin size, piracy, tectonism, and other events. First, the analysis to terrace gravel deposited by the Huangshui River, northeastern Tibet Plateau, China, shows statistically contrasting pebble populations for the oldest terrace (T7, Dadongling, 1.2. Ma) and the youngest terraces (T0-T3, ?. 0.15. Ma). Two fluvial processes are considered to explain the contrast in correlation between lithology and roundness in T7 gravel versus T0-T3 gravel: 1) reworking of T7 gravel into T0-T3 gravel and 2) growth in the size of the river basin between T7 and T0-T3 times. We favor growth in basin size as the dominant process, from comparison of pebble counts and contingency tables. Second, comparison of results from Huangshui River of China to three piedmont streams of the Rocky Mountains, USA highlights major differences in source terrane and history. Like Rocky Mountain piedmont gravel from Colorado examples, the Huangshui gravels show a preference (observed versus expected frequency) for rounded granite. But unlike Rocky Mountain gravel, Huangshui gravel shows a preference for angular quartzite and for rounded sandstone. In conclusion, contrasting behavior of lithologies during transport, not always apparent in raw pebble counts, is readily analyzed using contingency tables to identify the provenance of individual lithologies, including recycled clasts. Results of the analysis may help unravel river history, including changes in basin size and lithology. ?? 2009.

Lithological and fluvial controls on the geomorphology of tropical montane stream channels in Puerto Rico

Science.gov (United States)

Andrew S. Pike; F.N. Scatena; Ellen E. Wohl

2010-01-01

An extensive survey and topographic analysis of fi ve watersheds draining the Luquillo Mountains in north-eastern Puerto Rico was conducted to decouple the relative infl uences of lithologic and hydraulic forces in shaping the morphology of tropical montane stream channels. The Luquillo Mountains are a steep landscape composed of volcaniclastic and igneous rocks that...

Latest Paleocene lithologic and biotic events in neritic deposits of southwestern New Jersey

Science.gov (United States)

Gibson, Thomas G.; Bybell, Laurel M.; Owens, James P.

1993-01-01

In the southwestern New Jersey Coastal Plain, four drill holes contain continuous neritic sedimentation across the Paleocene/Eocene boundary (calcareous nannofossil Zone NP 9/NP 10 boundary). Significant lithologic and biotic changes occur in these strata near the top of the Paleocene. Global warming, increased precipitation, and other oceanographic and climatic events that have been recognized in high-latitude, deep-oceanic deposits of the latest Paleocene also influenced mid-latitude, shallow-marine, and terrestrial environments of the western North Atlantic. The diverse, well-preserved calcareous nannofossil flora that is present throughout the entire New Jersey boundary section accurately places these events within the uppermost part of the upper Paleocene Zone NP 9. Several rapid but gradational changes occur within a 1.1-m interval near the top of Zone NP 9. The changes include (1) a change in lithology from glauconitic quartz sand to clay, (2) a change in clay mineral suites from illite/smectite-dominated to kaolinite-dominated, (3) a change in benthic foraminiferal assemblages to a lower diversity fauna suggestive of low-oxygen environments, (4) a significant increase in planktonic foraminiferal abundance, and (5) an increased species turnover rate in marine calcareous nannofossils. Pollen was sparse in the New Jersey drill holes, but terrestrial sporomorph species in Virginia exhibit increased turnover rates at a correlative level. Foraminiferal assemblages and lithology indicate that relative sea level rose in New Jersey at the same time as these late Paleocene events occurred in late Biochron NP 9. The higher sea levels influenced sediment type and absolute abundance of planktonic foraminifers in the deposits. Above the initial increase of kaolinite in the upper part of Zone NP 9, the kaolinite percentage continues to increase, and the maximum kaolinite value occurs in the uppermost part of Zone NP 9. There are few changes in either the sediments or the

Summary of lithologic logging of new and existing boreholes at Yucca Mountain, Nevada, August 1993 to February 1994

Energy Technology Data Exchange (ETDEWEB)

Geslin, J.K.; Moyer, T.C.; Buesch, D.C.

1995-05-01

Yucca Mountain, Nevada, is being investigated as a potential site for a high-level radioactive waste repository. This report summarizes the lithologic logging of new and existing boreholes at Yucca Mountain that was done from August 1993 to February 1994 by the Rock Characteristics Section, Yucca Mountain Project Branch, US Geological Survey (USGS). Units encountered during logging include Quaternary-Tertiary alluvium/colluvium, Tertiary Rainier Mesa Tuff, all units in the Tertiary Paintbrush Group, Tertiary Calico Hills Formation and Tertiary Prow Pass Tuff. We present criteria used for recognition of stratigraphic contacts, logging results as tables of contact depths for core from neutron (UZN) boreholes and graphical lithologic logs for core from non-UZN boreholes, and descriptions of several distinctive nonwelded tuffs recognized in the PTn hydrogeologic unit of the Paintbrush Group.

Summary of lithologic logging of new and existing boreholes at Yucca Mountain, Nevada, August 1993 to February 1994

International Nuclear Information System (INIS)

Geslin, J.K.; Moyer, T.C.; Buesch, D.C.

1995-01-01

Yucca Mountain, Nevada, is being investigated as a potential site for a high-level radioactive waste repository. This report summarizes the lithologic logging of new and existing boreholes at Yucca Mountain that was done from August 1993 to February 1994 by the Rock Characteristics Section, Yucca Mountain Project Branch, US Geological Survey (USGS). Units encountered during logging include Quaternary-Tertiary alluvium/colluvium, Tertiary Rainier Mesa Tuff, all units in the Tertiary Paintbrush Group, Tertiary Calico Hills Formation and Tertiary Prow Pass Tuff. We present criteria used for recognition of stratigraphic contacts, logging results as tables of contact depths for core from neutron (UZN) boreholes and graphical lithologic logs for core from non-UZN boreholes, and descriptions of several distinctive nonwelded tuffs recognized in the PTn hydrogeologic unit of the Paintbrush Group

HCMM: Soil moisture in relation to geologic structure and lithology, northern California

Science.gov (United States)

Rich, E. I. (Principal Investigator)

1981-01-01

Some HCMM images of about 80,000 sq km in northern California were qualitatively evaluated for usefulness in regional geologic investigations of structure and lithology. The thermal characteristics recorded vary among the several geomorphic provinces and depends chiefly on the topographic expression and vegetation cover. Identification of rock types, or groups of rock types, was most successfully carried out within the semi-arid parts of the region; however, extensive features, such as faults, folds and volcanic fields could be delineated. Comparisons of seasonally obtained HCMM images were limited value, except in semi-arid regions.

Lithology and mineralogy recognition from geochemical logging tool data using multivariate statistical analysis.

Science.gov (United States)

Konaté, Ahmed Amara; Ma, Huolin; Pan, Heping; Qin, Zhen; Ahmed, Hafizullah Abba; Dembele, N'dji Dit Jacques

2017-10-01

The availability of a deep well that penetrates deep into the Ultra High Pressure (UHP) metamorphic rocks is unusual and consequently offers a unique chance to study the metamorphic rocks. One such borehole is located in the southern part of Donghai County in the Sulu UHP metamorphic belt of Eastern China, from the Chinese Continental Scientific Drilling Main hole. This study reports the results obtained from the analysis of oxide log data. A geochemical logging tool provides in situ, gamma ray spectroscopy measurements of major and trace elements in the borehole. Dry weight percent oxide concentration logs obtained for this study were SiO 2 , K 2 O, TiO 2 , H 2 O, CO 2 , Na 2 O, Fe 2 O 3 , FeO, CaO, MnO, MgO, P 2 O 5 and Al 2 O 3 . Cross plot and Principal Component Analysis methods were applied for lithology characterization and mineralogy description respectively. Cross plot analysis allows lithological variations to be characterized. Principal Component Analysis shows that the oxide logs can be summarized by two components related to the feldspar and hydrous minerals. This study has shown that geochemical logging tool data is accurate and adequate to be tremendously useful in UHP metamorphic rocks analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lithological and seasonal variations in radon concentrations in Cypriot groundwaters

International Nuclear Information System (INIS)

Tasoula Kiliari; Anastasia Tsiaili; Ioannis Pashalidis

2010-01-01

The paper presents and discusses radon activity concentrations in Cypriot groundwater systems as a function of the background lithology and seasonal/meteorological conditions using an airborne radon monitoring system (ARM) after separation of radon by out-gassing. Radiometric analysis of groundwater samples obtained from non-contaminated systems showed that radon concentration in groundwaters varies strongly (0.1-10 Bq L -1 ) depending mainly on the hosting geological matrix but also to lesser degree on atmospheric/meteorological conditions. The associated excess annual dose has been estimated to range between 10 -6 and 10 -4 mSv y -1 , which is an insignificant contribution to the radiation exposure of the Cypriot population caused by airborne radon (0.5 ± 0.4 mSv y -1 ). (author)

Peculiar lithological structure features of a productive horizon of the Shatlyk gas deposit

International Nuclear Information System (INIS)

Gergedava, Sh.K.; Sokolova, T.F.; Friman, Yu.T.

1975-01-01

Investigation results on the lithologic heterogeneity of the productive horizon in the Shatlyk gas field are cited. The work was performed by a set of commercial and geophysical procedures involving the method of spontaneous polarization potentials, side electrical sounding with five probes, cavernometry, microsounding, side logging and radiometry (neutron gamma method and gamma method). The structural peculiarity of the Shatlyk horizon was shown to possibly lead to non-uniform movement of seam waters during drilling and to flooding of wells

Lithologic influences on groundwater recharge through incised glacial till from profile to regional scales: Evidence from glaciated Eastern Nebraska

Science.gov (United States)

Gates, John B.; Steele, Gregory V.; Nasta, Paolo; Szilagyi, Jozsef

2014-01-01

Variability in sediment hydraulic properties associated with landscape depositional and erosional features can influence groundwater recharge processes by affecting soil-water storage and transmission. This study considers recharge to aquifers underlying river-incised glaciated terrain where the distribution of clay-rich till is largely intact in upland locations but has been removed by alluvial erosion in stream valleys. In a stream-dissected glacial region in eastern Nebraska (Great Plains region of the United States), recharge estimates were developed for nested profile, aquifer, and regional scales using unsaturated zone profile measurements (matric potentials, Cl- and 3H), groundwater tracers (CFC-12 and SF6), and a remote sensing-assisted water balance model. Results show a consistent influence of till lithology on recharge rates across nested spatial scales despite substantial uncertainty in all recharge estimation methods, suggesting that minimal diffuse recharge occurs through upland glacial till lithology whereas diffuse recharge occurs in river valleys where till is locally absent. Diffuse recharge is estimated to account for a maximum of 61% of total recharge based on comparison of diffuse recharge estimated from the unsaturated zone (0-43 mm yr-1) and total recharge estimated from groundwater tracers (median 58 mm yr-1) and water balance modeling (median 56 mm yr-1). The results underscore the importance of lithologic controls on the distributions of both recharge rates and mechanisms.

Study on the application of seismic sedimentology in a stratigraphic-lithologic reservoir in central Junggar Basin

Science.gov (United States)

Yu, Yixin; Xia, Zhongmou

2017-06-01

This paper discusses the research idea of description for stratigraphic-lithologic reservoir based on seismic sedimentology methods. The sandstone reservoir of Jurrassic XiShanyao Formation in Junggar Basin is studied according to the theory and approaches of seismic sedimentology. By making full use of borehole data, the technologies of layer correlation based on the stratigraphic sequence framework, the forward seismic modeling, the stratal slicing and lithologic inversion are applied. It describes the range of denudation line, the distribution characteristics of sedimentary facies of the strata, the vertical and horizontal distribution of sand bodies and the favourable oil-gas bearing prospective area. The results shows that study area are dominated braided delta deposition including underwater distributary channel and distributary bay microfacies, the nip-out lines of the formation are northeast to southwest from north to south, the second Middle Jurassic sand body is the most widely distributed one among three sand bodies, the prospective oil-gas bearing area located in the south part and around the YG2 well area. The study result is effective on the practice of exploration in study area.

Lithology, monsoon and sea-surface current control on provenance, dispersal and deposition of sediments over the Andaman continental shelf

Digital Repository Service at National Institute of Oceanography (India)

Damodararao, K.; Singh, S.K.; Rai, V.K.; Ramaswamy, V.; Rao, P.S.

, constrain their transport pathways and assess the factors influencing the erosion in the catchment and their dispersal and deposition over the Andaman Shelf region. Major elemental compositions of the shelf sediments suggest mafic lithology...

Slope position and Soil Lithological Effects on Live Leaf Nitrogen Concentration.

Science.gov (United States)

Szink, I.; Adams, T. S.; Orr, A. S.; Eissenstat, D. M.

2017-12-01

Soil lithology has been shown to have an effect on plant physiology from the roots to the leaves. Soils at ridgetop positions are typically more shallow and drier than soils at valley floor positions. Additionally, sandy soils tend to have a much lower water holding capacity and can be much harder for plants to draw nutrients from. We hypothesized that leaves from trees in shale derived soil at ridgetop positions will have lower nitrogen concentration than those in valley floor positions, and that this difference will be more pronounced in sandstone derived soils. This is due to the movement of nitrogen through the soil in a catchment, and the holding and exchange capacities of shale and sandstone lithologies. To test this, we collected live leaves using shotgun sampling from two locations in Central Pennsylvania from the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO); one location where soils are underlain by the Rose Hill Shale, and one from where soils are underlain by the Tuscarora Sandstone formation. We then measured, dried, and massed in order to determine specific leaf area (SLA). Afterwards, we powderized the leaves to determined their C:N ratio using a CE Instruments EA 1110 CHNS-O elemental Analyzer based on the "Dumas Method". We found that live leaves of the same species at higher elevations had lower nitrogen concentrations than those at lower elevations, which is consistent with our hypothesis. However, the comparison of leaves from all species in the catchment is not as strong, suggesting that there is a species specific effect on nitrogen concentration within leaves. We are currently processing additional leaves from other shale and sandstone sites. These results highlight the effect of abiotic environments on leaf nutrient concentrations, and the connection between belowground and aboveground tree physiology.

Mapping Post-Fire Vegetation Recovery at Different Lithologies of Taygetos mt (greece) with Multi-Temporal Remote Sensing Data

Science.gov (United States)

Vassilakis, Emmanuel; Mallinis, George; Christopoulou, Anastasia; Farangitakis, Georgios-Pavlos; Papanikolaou, Ioannis; Arianoutsou, Margarita

2017-04-01

Mt Taygetos (2407m), located at southern Peloponnese (Greece) suffered a large fire during the summer of 2007. The fire burned approximately 45% of the area covered by the endemic Greek fir (Abies cephalonica) and Black Pine (Pinus nigra) forest ecosystems. The aim of the current study is to examine the potential differences on post-fire vegetation recovery imposed by the lithology as well as the geomorphology of the given area over sites of the same climatic and landscape conditions (elevation, aspect, slope etc.). The main lithologies consist of carbonate, permeable, not easily erodible formations (limestones and marbles) and clastic, impermeable (schists, slate and flysch) erodible ones. A time-series of high spatial resolution satellite images were interpreted, analyzed and compared in order to detect changes in vegetation coverage which could prioritize areas of interest for fieldwork campaigns. The remote sensing datasets were acquired before (Ikonos-2), a few months after (Quickbird-2) and some years after (Worldview-3) the 2007 fire. High resolution Digital Elevation Model was used for the ortho-rectification and co-registration of the remote sensing data, but also for the extraction of the mountainous landscape characteristics. The multi-temporal image dataset was analyzed through GEographic-Object Based Image Analysis (GEOBIA). Objects corresponding to different vegetation types through time were identified through spectral and textural features. The classification results were combined with basic layers such as lithological outcrops, pre-fire vegetation, landscape morphology etc., supplementing a spatial geodatabase used for classifying burnt areas with varying post-fire plant community recovery. We validated the results of the classification during fieldwork and found that at a local scale, where the landscape features are quite similar, the bedrock type proves to be an important factor for vegetation recovery, as it clearly defines the soil generation

Lithostratigraphy does not always equal lithology: lessons learned in communicating uncertainty from stochastic modelling glacial and post glacial deposits in Glasgow U.K.

Science.gov (United States)

Kearsey, Tim; Williams, John; Finlayson, Andrew; Williamson, Paul; Dobbs, Marcus; Kingdon, Andrew; Campbell, Diarmad

2014-05-01

Geological maps and 3D models usually depict lithostragraphic units which can comprise of many different types of sediment (lithologies). The lithostratigraphic units shown on maps and 3D models of glacial and post glacial deposits in Glasgow are substantially defined by the method of the formation and age of the unit rather than its lithological composition. Therefore, a simple assumption that the dominant lithology is the most common constituent of any stratigraphic unit is erroneous and is only 58% predictive of the actual sediment types seen in a borehole. This is problematic for non-geologist such as planners, regulators and engineers attempting to use these models to inform their decisions and can lead to such users viewing maps and models as of limited use in such decision making. We explore the extent to which stochastic modelling can help to make geological models more predictive of lithology in heterolithic units. Stochastic modelling techniques are commonly used to model facies variations in oil field models. The techniques have been applied to an area containing >4000 coded boreholes to investigate the glacial and fluvial deposits in the centre of the city of Glasgow. We test the predictions from this method by deleting percentages of the control data and re-running the simulations to determine how predictability varies with data density. We also explore the best way of displaying such stochastic models to and suggest that displaying the data as probability maps rather than a single definitive answer better illustrates the uncertainties inherent in the input data. Finally we address whether is it possible truly to be able to predict lithology in such geological facies. The innovative Accessing Subsurface Knowledge (ASK) network was recently established in the Glasgow are by the British Geological Survey and Glasgow City Council to deliver and exchange subsurface data and knowledge. This provides an idea opportunity to communicate and test a range of

Radon in soil gas: distributions and correlations with the lithologies and pedologies of RMBH - Metropolitan region of Belo Horizonte - Minas Gerais - Brazil

International Nuclear Information System (INIS)

Lara, Evelise G.; Santos, Talita de O.; Oliveira, Arno Heeren de

2013-01-01

The concentration of radon in the soil gas is an important indicator to predict the radon geologic potential, usually indicated by Geological Radon Potential - GEORP, which is defined as the percent number of dwellings with indoor air radon concentration above the U.S.EPA action limit. The objective of this work was to investigate the distribution of radon concentration in soil gas and its relation with the pedologies and lithologies in the RMBH. The radon concentrations in soil gas were determined by using an AlphaGUARD monitor at 150 measurement points over the lithologies and pedologies of the area. The concentrations 226 Ra were determined by gamma spectrometry (HPGe) and U and Th by ICP-MS. The permeabilities of the soil were determined by using the RADON-JOK permeameter. Regarding pedologies, the perferric Red Latosols had the highest concentrations, with arithmetic mean to 60.6 ± 8.7 kBq.m -3 . Regarding lithologies, areas where the bedrocks are predominantly schists and metagraywackes showed the highest radon concentrations, with arithmetic mean to 46.5 ± 9.9 kBq.m -3 . The areas of lithology or pedology, in which the average radon concentrations are the highest also exhibit higher GEORP, e.g. for the perferric Red Latosol pedology shows GEORP of 26,5%. In this pedology, over 50% of the measurement points shows radon concentrations above of 50.0 kBq.m -3 , that, by the 'Swedish Criteria' classifies the area as high radon risk. The correlation with GEORP is even more significant when the radon concentration in soil gas is combined with soil permeability, through the Soil Radon Index indicator. (author)

Radon in soil gas: distributions and correlations with the lithologies and pedologies of RMBH - Metropolitan region of Belo Horizonte - Minas Gerais - Brazil

Energy Technology Data Exchange (ETDEWEB)

Lara, Evelise G.; Santos, Talita de O.; Oliveira, Arno Heeren de, E-mail: evelise.lara@gmail.com, E-mail: talitaolsantos@yahoo.com.br, E-mail: heeren@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, M.G (Brazil). Dept. de Engenharia Nuclear; Rocha, Zildete; Palmieri, Helena E. Leonhardt; Brito, Walter de; Araujo, Gabriela Bastos D. de, E-mail: rochaz@cdtn.br, E-mail: help@cdtn.br, E-mail: britow@cdtn.br, E-mail: gabibastosdias@hotmail.com [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2013-07-01

The concentration of radon in the soil gas is an important indicator to predict the radon geologic potential, usually indicated by Geological Radon Potential - GEORP, which is defined as the percent number of dwellings with indoor air radon concentration above the U.S.EPA action limit. The objective of this work was to investigate the distribution of radon concentration in soil gas and its relation with the pedologies and lithologies in the RMBH. The radon concentrations in soil gas were determined by using an AlphaGUARD monitor at 150 measurement points over the lithologies and pedologies of the area. The concentrations {sup 226}Ra were determined by gamma spectrometry (HPGe) and U and Th by ICP-MS. The permeabilities of the soil were determined by using the RADON-JOK permeameter. Regarding pedologies, the perferric Red Latosols had the highest concentrations, with arithmetic mean to 60.6 ± 8.7 kBq.m{sup -3}. Regarding lithologies, areas where the bedrocks are predominantly schists and metagraywackes showed the highest radon concentrations, with arithmetic mean to 46.5 ± 9.9 kBq.m{sup -3}. The areas of lithology or pedology, in which the average radon concentrations are the highest also exhibit higher GEORP, e.g. for the perferric Red Latosol pedology shows GEORP of 26,5%. In this pedology, over 50% of the measurement points shows radon concentrations above of 50.0 kBq.m{sup -3}, that, by the 'Swedish Criteria' classifies the area as high radon risk. The correlation with GEORP is even more significant when the radon concentration in soil gas is combined with soil permeability, through the Soil Radon Index indicator. (author)

HCMM: Soil moisture in relation to geologic structure and lithology, northern California. [Sacremento Valley

Science.gov (United States)

Rich, E. I. (Principal Investigator)

1979-01-01

The author has identified the following significant results. A preliminary analysis of the HCMM imagery of the project area indicated that locally some differentiation of lithologic units within the Northern Coast Range may be possible. Of significance, however, was a thermally cool linear area that appeared on the 30 May 1978 Nite-IR. This linear feature seemed to coincide with the Bear Mt. Fault and with the axis of the Chico Monocline along the eastern margin of the Sacramento Valley.

Enhancement of Jahani (Firouzabad salt dome lithological units, using principal components analysis

Directory of Open Access Journals (Sweden)

Houshang Pourcaseb

2016-04-01

Full Text Available In this study, principal components analysis was used to investigate lithological characteristics of Jahani salt dome, Firouzabad. The spectral curves of rocks in the study area show that the evaporate rocks have the highest reflectance at specified wavelengths. The highest reflection has been seen in gypsum and white salt, while minimal reflection can be observed in the igneous rocks from the region. The results show that PCs have significantly low information. It is clear that PC1 shows more information in the highest variance while PC2 has less information. Regional geological map and field controls show compatibility between the enhanced zones and outcrops in the field.

Use of lithological model for substantiating the outlook for gas content of red plate deposits (Saksoniy) of Poland

Energy Technology Data Exchange (ETDEWEB)

Ancupow, P W; Bakun, M M; Bojarska, J; Glowacki, E; Korab, Z; Sniegiriewa, O W

1981-01-01

The enterprise ''Geonafta'' (Warsaw) jointly with the VNIGNI (Moscow) has made detailed lithological-facial studies of the section of the red plate of the Polish lowland. A detailed lithological-stratigraphic plan has been developed with isolation of complexes, A, B, C, D, E/sub 1/ and E/sub 2/ based on the average quantity of mineral composition. Based on the plan, detailed correlation comparisons were made of the sections of the Saksaonskiy stage (upper part of the red plate). In the Polish part of the Permian basin, three main zones are isolated for dispersal of lithofacial complexes: A (southern zone), B (central and C (northern). For each zone typical lithofacial models are constructed which include five complexes (elements A, B, C, D, E) which characterize different of the Permian paleoriver (paleo-Olova). In addition to lithology, the elements are distinguished by the specific nature of formation of the gas traps. Facial analysis of the deposits associated with the paleo-Olava make it possible to predict the development of other river paleosystems in the southern part of the deposits of the Saksoniya of zones A, B, and C confirms the opinion of two stages of development of the Saksaonskiy basin which were distinguished according to conditions of sedimentation. A link has been established between the gas structural traps in the zone of premountain debris cones and zones of development of paleo-watersheds. This link which is specific for the Permian basin of Poland must be taken into consideration in determining the trends for further prospecting. New potential sites of gas prospecting in the Saksaonskiy deposits are associated in particular with the promising nature of the paleoelevation slopes.

Evaluation of tectonic impact on radon level of lithological units

International Nuclear Information System (INIS)

Wolkowicz, S.; Strzelecki, R.

2000-01-01

The radon potential maps of the Sudetes Mountains and Upper Silesian Coal Basin have been prepared on a base of arithmetic mean value of radon concentration in soil air in distinguished lithological/stratigraphic units. Both zones of shallow position of ground table and the fault zones influence value of this parameter: the first one affects in specific conditions lowering of background values, the second ones - origin of values several and teen times higher than rock background values. Estimation of power of tectonic influence on general radon potential of the lithological units has been made on a base of examination of histograms of distribution of radon concentration in soil air. In the Sudetes area, 0 % to about 30 % of the measurements is related to fault zones. Higher tectonic engagement (about 30 %) characterizes the Karkonosze Granites, Izera Gneisses and Strzegom Granites. In the cases of Karkonosze Granites and the Strzegom Granites, rock background values concentrations in soil air are a little than 50 kBq/m 3 , what is the value defined for lower threshold of high radon risk areas. In conclusion, presence of numerous fault zones and fissures increases radon risk category with one class. Background modal values of radon emanations, defined for the studied units, in the 5 cases fulfill criteria for medium radon risk areas, and in other cases do not exceed of the threshold 10 kBq/m 3 . It displays, that in the case of low radon potential rocks only a few-percent rich population of measurements related to tectonic zones, is sufficient to substantially deform of the image of the studied unit radon potential. For instance, medium radon potential characterizes the Klodzko - Zloty Stok Granites (the arithmetic mean value of this class is 36.15 kBq/m 3 , n=104) and small tectonic engagement (about 3.8 %). In the result the modal value belongs to the class 20-30 kBq/m 3 . The Poreba Beds in the Upper Silesian Coal Basin are characterised by almost the same radon

Application of cluster and discriminant analyses to diagnose lithological heterogeneity of the parent material according to its particle-size distribution

Science.gov (United States)

Giniyatullin, K. G.; Valeeva, A. A.; Smirnova, E. V.

2017-08-01

Particle-size distribution in soddy-podzolic and light gray forest soils of the Botanical Garden of Kazan Federal University has been studied. The cluster analysis of data on the samples from genetic soil horizons attests to the lithological heterogeneity of the profiles of all the studied soils. It is probable that they are developed from the two-layered sediments with the upper colluvial layer underlain by the alluvial layer. According to the discriminant analysis, the major contribution to the discrimination of colluvial and alluvial layers is that of the fraction >0.25 mm. The results of canonical analysis show that there is only one significant discriminant function that separates alluvial and colluvial sediments on the investigated territory. The discriminant function correlates with the contents of fractions 0.05-0.01, 0.25-0.05, and >0.25 mm. Classification functions making it possible to distinguish between alluvial and colluvial sediments have been calculated. Statistical assessment of particle-size distribution data obtained for the plow horizons on ten plowed fields within the garden indicates that this horizon is formed from colluvial sediments. We conclude that the contents of separate fractions and their ratios cannot be used as a universal criterion of the lithological heterogeneity. However, adequate combination of the cluster and discriminant analyses makes it possible to give a comprehensive assessment of the lithology of soil samples from data on the contents of sand and silt fractions, which considerably increases the information value and reliability of the results.

Landsat TM data processing for lithological discrimination in the Caraculo area (Namibe Province, SW Angola)

Science.gov (United States)

Alberti, A.; Alessandro, V.; Pieruccini, U.; Pranzini, E.

1993-10-01

Landsat TM data were used for lithological discrimination and mapping in the little-known, semiarid 900 km 2 area around Caraculo station and the middle course of the Rio Giraul (Namibe Province, SW Angola) following two main procedures. The first of these was based on visual evaluation of three-band composites, band-ratio composites and Principal Component Analysis. The second method relied on the extraction of spectral signatures, and their use to obtain automatic classifications. Satisfactory results were reached with the first procedure, thus allowing - with limited support of ground information — the draft of a lithological map, while the second method was not systematically efficient, even for confirmation of data acquired with the first procedure. Image interpretation suggests that an extensive but hithertoun differentiated metasedimentary complex consisting of a heterogeneous supracrustal sequence should be subdivided into at least two units. Field observations proved that one of these is marked by a notable frequency of marbles and the other is characterized by a widespread occurrence of amphibolitic bodies. Moreover, a belt of undetermined (thermally metamorphosed ?) metamorphic rocks is interposed between them. The distinction of so far unidentified units, though restricted to interpretation of processed Landsat TM data, has significant geological implications also in the regional context and will be helpful in guiding future work with conventional geological methods.

Evaluation of repeated measurements of radon-222 concentrations in well water sampled from bedrock aquifers of the Piedmont near Richmond, Virginia, USA: Effects of lithology and well characteristics

International Nuclear Information System (INIS)

Harris, Shelley A.; Billmeyer, Ernest R.; Robinson, Michael A.

2006-01-01

Radon ( 222 Rn) concentrations in 26 ground water wells of two distinct lithologies in the Piedmont of Virginia were measured to assess variation in ground water radon concentrations (GWRC), to evaluate differences in concentrations related to well characteristics, lithology, and spatial distributions, and to assess the feasibility of predicting GWRC. Wells were sampled in accordance with American Public Health Association Method 7500 Rn-B, with modifications to include a well shaft profile analysis that determined the minimum purge time sufficient to remove the equivalent of one column of water from each well. Statistically significant differences in GWRC were found in the Trssu (1482±1711 pCi/L) and Mpg (7750±5188 pCi/L) lithologies, however, no significant differences were found among GWRC at each well over time. Using multiple regression, 86% of the variability (R 2 ) in the GWRC was explained by the lithology, latitudinal class, and water table elevation of the wells. The GWRC in a majority of the wells studied exceed US Environmental Protection Agency designated maximum contaminant level and AMCL. Results support modifications to sampling procedures and indicate that, in previous studies, variations in GWRC concentrations over time may have been due in part to differences in sampling procedures and not in source water

Landsat 5 TM images and DEM in lithologic mapping of Payen Volcanic Field (Mendoza Province, Argentina)

International Nuclear Information System (INIS)

Fornaciai, A.; Bisson, M.; Mazzarini, F.; Del Carlo, P.; Pasquare, G.

2009-01-01

Satellite image such as Landsat 5 TM scene provides excellent representation of Earth and synoptic view of large geographic areas in different band combination. Landsat TM images allow automatic and semi-automatic classification of land cover, nevertheless the software frequently may some difficulties in distinguishing between similar radiometric surfaces. In this case, the use of Digital Elevation Model (DEM) can be an important tool to identify different surface covers. In this study, several False Color Composite (FCC) of Landsat 5 TM Image, DEM and the respective draped image of them, were used to delineate lithological boundaries and tectonic features of regional significance of the Paven Volcanic Field (PVF). PFV is a Quaternary fissural structure belonging to the black-arc extensional areas of the Andes in the Mendoza Province (Argentina) characterized by many composite basaltic lava flow fields. The necessity to identify different lava flows with the same composition, and then with same spectral features, allows to highlight the improvement of synergic use of TM images and shaded DEM in the visual interpretation. Information obtained from Satellite data and DEM have been compared with previous geological maps and transferred into a topographical base map. Based on these data a new lithological map at 1:100.000 scale has been presented [it

Use of spectral gamma ray as a lithology guide for fault rocks: A case study from the Wenchuan Earthquake Fault Scientific Drilling project Borehole 4 (WFSD-4).

Science.gov (United States)

Amara Konaté, Ahmed; Pan, Heping; Ma, Huolin; Qin, Zhen; Guo, Bo; Yevenyo Ziggah, Yao; Kounga, Claude Ernest Moussounda; Khan, Nasir; Tounkara, Fodé

2017-10-01

The main purpose of the Wenchuan Earthquake Fault Scientific drilling project (WFSD) was to produce an in-depth borehole into the Yingxiu-Beichuan (YBF) and Anxian-Guanxian faults in order to gain a much better understanding of the physical and chemical properties as well as the mechanical faulting involved. Five boreholes, namely WFSD-1, WFSD-2, WFSD-3P, WFSD-3 and WFSD-4, were drilled during the project entirety. This study, therefore, presents first-hand WFSD-4 data on the lithology (original rocks) and fault rocks that have been obtained from the WFSD project. In an attempt to determine the physical properties and the clay minerals of the lithology and fault rocks, this study analyzed the spectral gamma ray logs (Total gamma ray, Potassium, Thorium and Uranium) recorded in WFSD-4 borehole on the Northern segment of the YBF. The obtained results are presented as cross-plots and statistical multi log analysis. Both lithology and fault rocks show a variability of spectral gamma ray (SGR) logs responses and clay minerals. This study has shown the capabilities of the SGR logs for well-logging of earthquake faults and proves that SGR logs together with others logs in combination with drill hole core description is a useful method of lithology and fault rocks characterization. Copyright © 2017 Elsevier Ltd. All rights reserved.

Integration of DAS (distributed acoustic sensing) vertical seismic profile and geostatistically modeled lithology data to characterize an enhanced geothermal system.

Science.gov (United States)

Cronin, S. P.; Trainor Guitton, W.; Team, P.; Pare, A.; Jreij, S.; Powers, H.

2017-12-01

In March 2016, a 4-week field data acquisition took place at Brady's Natural Lab (BNL), an enhanced geothermal system (EGS) in Fallan, NV. During these 4 weeks, a vibe truck executed 6,633 sweeps, recorded by nodal seismometers, horizontal distributed acoustic sensing (DAS) cable, and 400 meters of vertical DAS cable. DAS provides lower signal to noise ratio than traditional geophones but better spatial resolution. The analysis of DAS VSP included Fourier transform, and filtering to remove all up-going energy. Thus, allowing for accurate first arrival picking. We present an example of the Gradual Deformation Method (GDM) using DAS VSP and lithological data to produce a distribution of valid velocity models of BNL. GDM generates continuous perturbations of prior model realizations seeking the best match to the data (i.e. minimize the misfit). Prior model realizations honoring the lithological data were created using sequential Gaussian simulation, a commonly used noniterative geostatistical method. Unlike least-squares-based methods of inversion, GDM readily incorporates a priori information, such as a variogram calculated from well-based lithology information. Additionally, by producing a distribution of models, as opposed to one optimal model, GDM allows for uncertainty quantification. This project aims at assessing the integrated technologies ability to monitor changes in the water table (possibly to one meter resolution) by exploiting the dependence of seismic wave velocities on water saturation of the subsurface. This project, which was funded in part by the National Science Foundation, is a part of the PoroTomo project, funded by a grant from the U.S. Department of Energy.

Geochemical insights into the lithology of mantle sources for Cenozoic alkali basalts in West Qinling, China

Science.gov (United States)

Dai, Li-Qun; Zheng, Fei; Zhao, Zi-Fu; Zheng, Yong-Fei

2018-03-01

Although alkali basalts are common in oceanic islands and continental rifts, the lithology of their mantle sources is still controversial. While the peridotite is usually viewed as a common source lithology, there are increasing studies suggesting significant contributions from ultramafic metasomatites such as carbonated peridotite, pyroxenite and hornblendite to the origin of alkali basalts. The present study indicates that carbonated peridotite plus hornblendite would have served as the mantle sources of Cenozoic alkali basalts from the West Qinling orogen in China. The target basalts show low SiO2 contents of 36.9 to 40.8 wt% and highly variable Na2O + K2O contents from 0.86 to 4.77 wt%, but high CaO contents of 12.5 to 16.3 wt% and CaO/Al2O3 ratios of 1.42 to 2.19. They are highly enriched in the majority of incompatible trace elements, but depleted in Rb, K, Pb, Zr, Hf, and Ti. Furthermore, they exhibit high (La/Yb)N, Zr/Hf, Ce/Pb and Nb/Ta ratios, but low Ti/Eu and Hf/Sm ratios. Generally, with increasing (La/Yb)N and CaO/Al2O3 ratios, their Ti/Eu and Hf/Sm ratios decrease whereas their Zr/Hf, Ce/Pb and Nb/Ta ratios increase. These major and trace element features are similar to those of carbonatites and hornblendite-derived melts to some extent, but significantly different from those of mid-ocean ridge basalts (MORB). This suggests that the alkali basalts would be originated from metasomatic mantle sources. A comparison of the major-trace elements in the alkali basalts with those of some representative mantle-derived melts indicates that the source lithology of alkali basalts is a kind of ultramafic metasomatites that are composed of carbonated peridotite and hornblendite. Such metasomatites would be generated by reaction of the depleted MORB mantle peridotite with hydrous, carbonate-bearing felsic melts derived from partial melting of the subducted Paleotethyan oceanic crust. Therefore, the melt-peridotite reaction at the slab-mantle interface in the

The StreamCat Dataset: Accumulated Attributes for NHDPlusV2 (Version 2.1) Catchments for the Conterminous United States: Surficial Lithology in Watershed

Data.gov (United States)

U.S. Environmental Protection Agency — This dataset represents the density of 18 USGS lithology classes within individual, local NHDPlusV2 catchments and upstream, contributing watersheds(see Data Sources...

Lithological and land-use based assessment of heavy metal pollution in soils surrounding a cement plant in SW Europe.

Science.gov (United States)

Cutillas-Barreiro, Laura; Pérez-Rodríguez, Paula; Gómez-Armesto, Antía; Fernández-Sanjurjo, María José; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino; Arias-Estévez, Manuel; Nóvoa-Muñoz, Juan Carlos

2016-08-15

We study the influence of phasing out a cement plant on the heavy metal (Hg, Pb and Cr) content in the surrounding soils, taking into account factors often neglected, such as contributions due to local lithology or land use. The range of total Hg was 10-144µg kg(-1), reaching up to 41 and 145mgkg(-1) for total contents of Pb and Cr, respectively. Forest soils showed higher concentration of Hg than prairie soils, indicating the importance of land use on the accumulation of volatile heavy metals in soils. In forest soils, total Hg showed a trend to decrease with soil depth, whereas in prairie soils the vertical pattern of heavy metal concentrations was quite homogeneous. In most cases, the distance to the cement plant was not a factor of influence in the soils content of the analyzed heavy metals. Total Pb and Cr contents in soils nearby the cement plant were quite similar to those found in the local lithology, resulting in enrichment factor values (EF's) below 2. This suggests that soil parent material is the main source of these heavy metals in the studied soils, while the contribution of the cement plant to Pb and Cr soil pollution was almost negligible. On the contrary, the soils surrounding the cement plant accumulate a significant amount of Hg, compared to the underlying lithology. This was especially noticeable in forest soils, where Hg EF achieved values up to 36. These results are of relevance, bearing in mind that Hg accumulation in soils may be an issue of environmental concern, particularly in prairie soils, where temporal flooding can favor Hg transformation to highly toxic methyl-Hg. In addition, the concurrence of acid soils and total-Cr concentrations in the range of those considered phytotoxic should be also stressed. Copyright © 2016 Elsevier B.V. All rights reserved.

Lithologic Controls on Structure Highlight the Role of Fluids in Failure of a Franciscan Complex Accretionary Prism Thrust Fault

Science.gov (United States)

Bartram, H.; Tobin, H. J.; Goodwin, L. B.

2015-12-01

Plate-bounding subduction zone thrust systems are the source of major earthquakes and tsunamis, but their mechanics and internal structure remain poorly understood and relatively little-studied compared to faults in continental crust. Exposures in exhumed accretionary wedges present an opportunity to study seismogenic subduction thrusts in detail. In the Marin Headlands, a series of thrusts imbricates mechanically distinct lithologic units of the Mesozoic Franciscan Complex including pillow basalt, radiolarian chert, black mudstone, and turbidites. We examine variations in distribution and character of structure and vein occurrence in two exposures of the Rodeo Cove thrust, a fossil plate boundary exposed in the Marin Headlands. We observe a lithologic control on the degree and nature of fault localization. At Black Sand Beach, deformation is localized in broad fault cores of sheared black mudstone. Altered basalts, thrust over greywacke, mudstone, and chert, retain their coherence and pillow structures. Veins are only locally present. In contrast, mudstone is virtually absent from the exposure 2 km away at Rodeo Beach. At this location, deformation is concentrated in the altered basalts, which display evidence of extensive vein-rock interaction. Altered basalts exhibit a pervasive foliation, which is locally disrupted by both foliation-parallel and cross-cutting carbonate-filled veins and carbonate cemented breccia. Veins are voluminous (~50%) at this location. All the structures are cut by anastomosing brittle shear zones of foliated cataclasite or gouge. Analyses of vein chemistry will allow us to compare the sources of fluids that precipitated the common vein sets at Rodeo Beach to the locally developed veins at Black Sand Beach. These observations lead us to hypothesize that in the absence of a mechanically weak lithology, elevated pore fluid pressure is required for shear failure. If so, the vein-rich altered basalt at Rodeo Beach may record failure of an

Lithology and Stratigraphy of Holes Drilled in LANL-Use Areas of the Nevada Test Site

Energy Technology Data Exchange (ETDEWEB)

Lance B. Prothro; Sigmund L. Drellack, Jr.; Brian M. Allen

1999-07-01

Geologic data for ten holes drilled in areas used by Los Alamos National Laboratory at the Nevada Test Site are presented in this report. The holes include emplacement holes, instrumentation holes, and Underground Test Area wells drilled during calendar years 1991 through 1995. For each hole a stratigraphic log, a detailed lithologic log, and one or two geologic cross sections are presented, along with a supplemental data sheet containing information about the drilling operations, geology, or references. For three of the holes, graphic data summary sheets with geologic and geophysical data are provided as plates.

Physical and lithological properties Oligocene-Miocene formations of the Okhotsk-Kamchatka Basin (to 85-th Anniversary of Professor Yuri Konstantinovich Burlin

Directory of Open Access Journals (Sweden)

E.E. Karnyushina

2017-05-01

Full Text Available The purpose of the investigation was the prediction of physical and lithological properties of volcanogenic-sedimentary formations at different depths. For this purpose Oligocene-Miocene sediments from a number of wells within the Icha and Kolpakovsky depressions of Okhotsk-Kamchatka oil and gas basin have been studied. Relationship between temperature and fluid conditions of the katagenesis zone and the change in the rocks composition, their porosity, permeability, density, thermal conductivity were identified. Superposed phenomena and characteristics of the reservoir rocks transformations within the water-hydrocarbon contacts in the gas and gas condensate pools have been considered. The relationship between volcanogenic-sedimentary rocks physical and lithological properties and the formation of non-stationary geothermal regime has been shown. The article is devoted to the head of these investigations – Professor Yuri Konstantinovich Burlin (1931-2011. 12 Oktober this year, he would have turned his 85 years.

Evaluation of the lithology contents and types of clay minerals using downhole spectral analyzer of natural gamma radiation

International Nuclear Information System (INIS)

Zivanov, M.; Savicic, M.; Grbovic, G.

1992-01-01

The microprocessor downhole spectrum analyzer of natural gamma radiation is an important part of the new generation of geophysical well logging systems. This instrument produces complete energy spectra of the penetrated formations. here physical principles of logging are shown. based on the logging results from one of the wells complex lithology was identified, together with shale contents in the formation and types of clay and minerals. (author)

Qualitatively Modeling solute fate and transport across scales in an agricultural catchment with diverse lithology

Science.gov (United States)

Wayman, C. R.; Russo, T. A.; Li, L.; Forsythe, B.; Hoagland, B.

2017-12-01

As part of the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) project, we have collected geochemical and hydrological data from several subcatchments and four monitoring sites on the main stem of Shaver's Creek, in Huntingon county, Pennsylvania. One subcatchment (0.43 km2) is under agricultural land use, and the monitoring locations on the larger Shaver's Creek (up to 163 km2) drain watersheds with 0 to 25% agricultural area. These two scales of investigation, coupled with advances made across the SSHCZO on multiple lithologies allow us to extrapolate from the subcatchment to the larger watershed. We use geochemical surface and groundwater data to estimate the solute and water transport regimes within the catchment, and to show how lithology and land use are major controls on ground and surface water quality. One area of investigation includes the transport of nutrients between interflow and regional groundwater, and how that connectivity may be reflected in local surface waters. Water and nutrient (Nitrogen) isotopes, will be used to better understand the relative contributions of local and regional groundwater and interflow fluxes into nearby streams. Following initial qualitative modeling, multiple hydrologic and nutrient transport models (e.g. SWAT and CYCLES/PIHM) will be evaluated from the subcatchment to large watershed scales. We will evaluate the ability to simulate the contributions of regional groundwater versus local groundwater, and also impacts of agricultural land management on surface water quality. Improving estimations of groundwater contributions to stream discharge will provide insight into how much agricultural development can impact stream quality and nutrient loading.

Ground deformation at collapse calderas: influence of host rock lithology and reservoir multiplicity

Energy Technology Data Exchange (ETDEWEB)

Geyer, A; Gottsmann, J [Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queen' s Road, BS8 1RJ, Bristol (United Kingdom)], E-mail: A.GeverTraver@bristol.ac.uk

2008-10-01

A variety of source mechanisms have been proposed to account for observed caldera deformation. Here we present a systematic set of new results from numerical forward modelling using a Finite Element Method. which provides a link between measured ground deformation and the inaccessible deformation source. We simulate surface displacements due to pressure changes in a shallow oblate reservoir overlain by host rock with variable mechanical properties. We find that the amplitude and wavelength of resultant ground deformation is dependent on the distribution of mechanically stiff and soft lithologies and their relative distribution above a reservoir. In addition, we note an influence of layering on the critical ratio of horizontal over vertical displacements, a criterion employed to discriminate between different finite source geometries.

Effect of lithological variations of mine roof on chock shield support using numerical modeling technique

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-09-15

Interaction between chock shield supports, the most popular powered supports in Indian longwall mines, and surrounding coal measure strata is analyzed using finite element models. Thickness and material properties of the main roof, the immediate roof and the coal seam are varied to simulate various geological conditions of Indian coal measure strata. Contact/gap elements are inserted in between the main roof and overburden layer to allow strata separation. Nonlinear material properties are applied with plastic corrections based on Drucker-Prager yield criterion. This paper illustrates effects of lithological variations on shield load, abutment stress, yield zone and longwall face convergence.

Sealing of exploratory boreholes in clay reactivity of ordinary portland cement (OPC) grouts and various lithologies from the Harwell research site. Volume 1

International Nuclear Information System (INIS)

Milodowski, A.E.; George, I.A.; Bloodworth, A.J.; Robins, N.S.

1986-01-01

As part of a research programme on the disposal of radioactive wastes in clay, Ordinary Portland Cement (OPC) has been used in the completion of boreholes on the Harwell Research Site, AERE, Oxfordshire. The purpose of this study was to examine the effect of OPC and the alkaline pore fluids generated during its setting on the various lithological types encountered in the boreholes. To facilitate this, samples of core representing the various rock types were selected and cement-rock composites were prepared from these in the laboratory to simulate the borehole cements. After a curing period of 15 months the cores and associated cement plugs were examined for any signs of reactivity or bonding. The best cement-rock bonding was shown by naturally well-cemented sandstone and limestone lithologies. Although no significant chemical reaction was seen to have occurred between OPC and rock, the OPC appears able to bind onto the rock surface because of the rigidity of the rock surface. Therefore, the best cement rock bonding and seal with OPC may be expected in the limestones of the Great Oolite Group, Inferior Oolite Group and parts of the Corallian beds. Because of the reactivity of OPC towards certain lithologies a better borehole seal in such a sedimentary sequence might be achieved using a bentonite backfill in those parts of the sequence which either react with or bond only weakly to OPC

Mapping groundwater reserves in northwestern Cambodia with the combined use of data from lithologs and time-domain-electromagnetic and magnetic-resonance soundings

Science.gov (United States)

Valois, Remi; Vouillamoz, Jean-Michel; Lun, Sambo; Arnout, Ludovic

2018-01-01

Lack of access to water is the primary constraint to development in rural areas of northwestern Cambodia. Communities lack water for both domestic and irrigation purposes. To provide access to drinking water, governmental and aid agencies have focused on drilling shallow boreholes but they have not had a clear understanding of groundwater potential. The goal of this study has been to improve hydrogeological knowledge of two districts in Oddar Meanchey Province by analyzing borehole lithologs and geophysical data sets. The comparison of 55 time-domain electromagnetic (TEM) soundings and lithologs, as well as 66 magnetic-resonance soundings (MRS) with TEM soundings, allows a better understanding of the links between geology, electrical resistivity and hydrogeological parameters such as the specific yield (S y) derived from MRS. The main findings are that water inflow and S y are more related to electrical resistivity and elevation than to the litholog description. Indeed, conductive media are associated with a null value of S y, whereas resistive rocks at low elevation are always linked to strictly positive S y. A new methodology was developed to create maps of groundwater reserves based on 612 TEM soundings and the observed relationship between resistivity and S y. TEM soundings were inverted using a quasi-3D modeling approach called `spatially constrained inversion'. Such maps will, no doubt, be very useful for borehole siting and in the economic development of the province because they clearly distinguish areas of high groundwater-reserves potential from areas that lack reserves.

Subsurface imaging of water electrical conductivity, hydraulic permeability and lithology at contaminated sites by induced polarization

DEFF Research Database (Denmark)

Maurya, P. K.; Balbarini, Nicola; Møller, I.

2018-01-01

At contaminated sites, knowledge about geology and hydraulic properties of the subsurface and extent of the contamination is needed for assessing the risk and for designing potential site remediation. In this study, we have developed a new approach for characterizing contaminated sites through time...... geological logs. On average the IP-derived and measured permeability values agreed within one order of magnitude, except for those close to boundaries between lithological layers (e.g. between sand and clay), where mismatches occurred due to the lack of vertical resolution in the geophysical imaging...

The nevado-filábride complex in the western part of Sierra de los Filabres (Betic Internal Zone), structure and lithologic succession

Energy Technology Data Exchange (ETDEWEB)

Sanz de Galdeano, C.; López Garrido, A.

2016-07-01

In the western part of Sierra de los Filabres (in the Nevado-Filábride Complex, within the Betic Internal Zone) several tectonic units have been described, in varying numbers depending on the author describing them. However, new cartographical data show that the limits of these units pass through the lithological formations without displacing them. Moreover, the rocks belonging to some units that are supposedly situated in a lower tectonic position really belong to higher formations. From bottom to top, these lithological formations are the following: (1) dark schists and quartzites; (2) quartzites, sandstones, sands, lutites, schists, and mica schists; (3) schists; (4) marbles, schists, and mica schists. High-angle reverse faults are associated with the great E-W anticline of Sierra de los Filabres. The existence of sands and apparent lutites visibly interlayered between rocks, such as schists and mica schists with garnets, poses a metamorphic problem that has not as yet been addressed. (Author)

Lithological control on gas hydrate saturation as revealed by signal classification of NMR logging data

Science.gov (United States)

Bauer, Klaus; Kulenkampff, Johannes; Henninges, Jan; Spangenberg, Erik

2015-09-01

In this paper, nuclear magnetic resonance (NMR) downhole logging data are analyzed with a new strategy to study gas hydrate-bearing sediments in the Mackenzie Delta (NW Canada). In NMR logging, transverse relaxation time (T2) distribution curves are usually used to determine single-valued parameters such as apparent total porosity or hydrocarbon saturation. Our approach analyzes the entire T2 distribution curves as quasi-continuous signals to characterize the rock formation. We apply self-organizing maps, a neural network clustering technique, to subdivide the data set of NMR curves into classes with a similar and distinctive signal shape. The method includes (1) preparation of data vectors, (2) unsupervised learning, (3) cluster definition, and (4) classification and depth mapping of all NMR signals. Each signal class thus represents a specific pore size distribution which can be interpreted in terms of distinct lithologies and reservoir types. A key step in the interpretation strategy is to reconcile the NMR classes with other log data not considered in the clustering analysis, such as gamma ray, hydrate saturation, and other logs. Our results defined six main lithologies within the target zone. Gas hydrate layers were recognized by their low signal amplitudes for all relaxation times. Most importantly, two subtypes of hydrate-bearing shaly sands were identified. They show distinct NMR signals and differ in hydrate saturation and gamma ray values. An inverse linear relationship between hydrate saturation and clay content was concluded. Finally, we infer that the gas hydrate is not grain coating, but rather, pore filling with matrix support is the preferred growth habit model for the studied formation.

Lithologic and hydrologic controls of mixed alluvial-bedrock channels in flood-prone fluvial systems: bankfull and macrochannels in the Llano River watershed, central Texas, USA

Science.gov (United States)

Heitmuller, Frank T.; Hudson, Paul F.; Asquith, William H.

2015-01-01

The rural and unregulated Llano River watershed located in central Texas, USA, has a highly variable flow regime and a wide range of instantaneous peak flows. Abrupt transitions in surface lithology exist along the main-stem channel course. Both of these characteristics afford an opportunity to examine hydrologic, lithologic, and sedimentary controls on downstream changes in channel morphology. Field surveys of channel topography and boundary composition are coupled with sediment analyses, hydraulic computations, flood-frequency analyses, and geographic information system mapping to discern controls on channel geometry (profile, pattern, and shape) and dimensions along the mixed alluvial-bedrock Llano River and key tributaries. Four categories of channel classification in a downstream direction include: (i) uppermost ephemeral reaches, (ii) straight or sinuous gravel-bed channels in Cretaceous carbonate sedimentary zones, (iii) straight or sinuous gravel-bed or bedrock channels in Paleozoic sedimentary zones, and (iv) straight, braided, or multithread mixed alluvial–bedrock channels with sandy beds in Precambrian igneous and metamorphic zones. Principal findings include: (i) a nearly linear channel profile attributed to resistant bedrock incision checkpoints; (ii) statistically significant correlations of both alluvial sinuosity and valley confinement to relatively high f (mean depth) hydraulic geometry values; (iii) relatively high b (width) hydraulic geometry values in partly confined settings with sinuous channels upstream from a prominent incision checkpoint; (iv) different functional flow categories including frequently occurring events (high f values (most ≤ 0.45) that develop at sites with unit stream power values in excess of 200 watts per square meter (W/m2); and (vi) downstream convergence of hydraulic geometry exponents for bankfull and macrochannels, explained by co-increases of flood magnitude and noncohesive sandy sediments that collectively

Quantification of soil loss in various lithological areas of the western Middle Atlas Central: application to the Ras-Elma, Tamelalet and Sebab watershed (Tigrigra watershed, Morocco)

Science.gov (United States)

Achiban, Hassan; Taous, Ali; El-Khantoury, Ismail; El Mderssa, Mohamed; Amechrouq, Ali

2018-05-01

The present study proposes to evaluate the extent of erosion according to the lithology in three sub-watersheds (Ras Elma, Sebab and Tamelalet) belonging to the Tigrigra basin and evolving in humid climatic context. The methodology adopts the revised universal soil loss equation (RUSLE). The results obtained make it possible to establish erosion class maps via GIS. A clear spatial difference in soil loss is observed, between the three sub-basins and in proportion to the lithology: on average 42.15 t/ha/year on Paleozoic schistose soils, against 17.06 t/ha/year on carbonate substrates Mesozoic and 8.46 t/ha/year on quaternary basalts. Correlations between soil loss and RUSLE factors are established. Soil infiltration regimes on different substrates are studied.

Lithological and structural bedrock model of the Haestholmen study site, Loviisa, SE Finland

International Nuclear Information System (INIS)

Front, K.; Paulamaeki, S.; Ahokas, H.; Anttila, P.

1999-10-01

The Haestholmen study site is located within the anorogenic Wiborg rapakivi granite batholith, 1640 1630 Ma in age. The bedrock consists of various rapakivi granites, which can be divided into three groups or lithological units: (1) wiborgite and pyterlite, (2) porphyritic rapakivi granite, and (3) even-grained or weakly porphyritic rapakivi granite, pyterlite being the dominant rock type. The evengrained and weakly porphyritic rapakivi granite has been interpreted to form a younger intrusive unit with a thickness of ca. 500 m, dipping approx. 20 deg to the NNW-NNE. Surface fractures form a distinct orthogonal system, with three perpendicular fracture directions: fractures dipping steeply (dip >75 deg) to the NE-SW and NW-SE plus subhorizontal (dip -3 m 2 /s to 1*10 -7 m 2 /s, the average being 1-10 -5 m 2 /s. (orig.)

The Messinian evaporites in the Levant Basin: lithology, deformation and its evolution

Science.gov (United States)

Feng, Ye; Steinberg, Josh; Reshef, Moshe

2017-04-01

The lithological composition of the Messinian evaporite in the Levant Basin remains controversial and salt deformation mechanisms are still not fully understood, due to the lack of high resolution 3D depth seismic data and well logs that record the entire evaporite sequence. We demonstrate how 3D Pre-stack depth migration (PSDM) and intra-salt tomography can lead to improved salt imaging. Using 3D PSDM seismic data with great coverage and deepwater well log data from recently drilled boreholes, we reveal intra-salt reflective units associated with thin clastic layers and a seismic transparent background consisting of uniform pure halite. Structural maps of all internal reflectors are generated for stratigraphy and attributes analysis. High amplitude fan structures in the lowermost intra-salt reflector are observed, which may indicate the source of the clastic formation during the Messinian Salinity Crisis (MSC). The Messinian evaporite in the Levant Basin comprises six units; the uppermost unit thickens towards the northwest, whereas the other units are uniform in thickness. The top of salt (TS) horizon is relatively horizontal, while all other intra-salt reflectors and base of salt (BS) dip towards the northwest. Different seismic attributes are used for identification of intra-salt deformation patterns. Maximum curvature maps show NW-striking thrust faults on the TS and upper intra-salt units, and dip azimuth maps are used to show different fold orientations between the TS and intra-salt units, which indicate a two-phase deformation mechanism: basin NW tilting as syn-depositional phase and NNE spreading of Plio-Pleistocene overburden as post-depositional phase. RMS amplitude maps are used to identify a channelized system on the TS. An evaporite evolution model during the MSC of the Levant Basin is therefore established based on all the observations. Finally the mechanical properties of the salts will be utilized to explore salt deformation in the Levant Basin

The influence of lithology on surface water sources | Science ...

Science.gov (United States)

Understanding the temporal and spatial variability of surface water sources within a basin is vital to our ability to manage the impacts of climate variability and land cover change. Water stable isotopes can be used as a tool to determine geographic and seasonal sources of water at the basin scale. Previous studies in the Coastal Range of Oregon reported that the variation in the isotopic signatures of surface water does not conform to the commonly observed “rainout effect”, which exhibits a trend of increasing isotopic depletion with rising elevation. The primary purpose of this research is to investigate the mechanisms governing seasonal and spatial variations in the isotopic signature of surface waters within the Marys River Basin, located in the leeward side of the Oregon Coastal Range. Surface water and precipitation samples were collected every 2-3 weeks for isotopic analysis of δ18O and δ2H for one year. Results indicate a significant difference in isotopic signature between watersheds underlain by basalt and sandstone. The degree of separation was the most distinct during the summer when low flows reflect deeper groundwater sources, whereas isotopic signatures during the rainy season (fall and winter) showed a greater degree of similarity between the two lithologies. This indicates that baseflow within streams drained by sandstone versus basalt is being supplied from two distinctly separate water sources. In addition, Marys River flow at the outle

Lithologic Control on the Form of Soil Mantled Hillslopes

Science.gov (United States)

Johnstone, S. A.; Hilley, G. E.

2014-12-01

Slopes on steady-state soil-mantled hillslopes tend to increase downslope in a way that balances local transport capacity with the sediment supplied from progressively larger source areas. Most predictions for the transport of soil depend purely on topographic slope and constants. Thus, soil mantled topography should evolve toward smooth forms in which soils act to buffer these forms from the underlying geologic structure. However, in the Gabilan Mesa, CA, oscillations in the slope of soil-mantled hillslopes mirror oscillations in the underlying stratigraphy. Using field measurements of stratigraphy and soil depths, topographic analysis, and numerical modeling, we demonstrate that variations in rock type can impact the form of soil-mantled hillslopes. Specifically, variations in the properties of underlying rocks may yield different soil thicknesses. Balancing transport rates across these variations in thickness requires slopes to change when soil transport depends on both soil thickness and slope. A compilation of published data on the variation in activity with depth of various transport processes provides the basis for a geomorphic transport law (GTL) that generalizes the depth dependence of various transport processes. While this GTL is explicitly depth dependent, it is also capable of describing situations in which hillslope transport is relatively insensitive to variations in thickness and therefore essentially equivalent to existing formulations. We use dimensional analysis and numerical modeling to demonstrate the conditions under which transport on soil mantled slopes, and consequently topographic forms, may be sensitive to variations in soil thickness and therefore lithology.

Lithologic and hydrologic controls of mixed alluvial-bedrock channels in flood-prone fluvial systems: bankfull and macrochannels in the Llano River watershed, central Texas, USA

Science.gov (United States)

Heitmuller, Frank T.; Hudson, Paul F.; Asquith, William H.

2015-01-01

The rural and unregulated Llano River watershed located in central Texas, USA, has a highly variable flow regime and a wide range of instantaneous peak flows. Abrupt transitions in surface lithology exist along the main-stem channel course. Both of these characteristics afford an opportunity to examine hydrologic, lithologic, and sedimentary controls on downstream changes in channel morphology. Field surveys of channel topography and boundary composition are coupled with sediment analyses, hydraulic computations, flood-frequency analyses, and geographic information system mapping to discern controls on channel geometry (profile, pattern, and shape) and dimensions along the mixed alluvial-bedrock Llano River and key tributaries. Four categories of channel classification in a downstream direction include: (i) uppermost ephemeral reaches, (ii) straight or sinuous gravel-bed channels in Cretaceous carbonate sedimentary zones, (iii) straight or sinuous gravel-bed or bedrock channels in Paleozoic sedimentary zones, and (iv) straight, braided, or multithread mixed alluvial–bedrock channels with sandy beds in Precambrian igneous and metamorphic zones. Principal findings include: (i) a nearly linear channel profile attributed to resistant bedrock incision checkpoints; (ii) statistically significant correlations of both alluvial sinuosity and valley confinement to relatively high f (mean depth) hydraulic geometry values; (iii) relatively high b (width) hydraulic geometry values in partly confined settings with sinuous channels upstream from a prominent incision checkpoint; (iv) different functional flow categories including frequently occurring events (< 1.5-year return periods) that mobilize channel-bed material and less frequent events that determine bankfull channel (1.5- to 3-year return periods) and macrochannel (10- to 40-year return periods) dimensions; (v) macrochannels with high f values (most ≤ 0.45) that develop at sites with unit stream power values in excess

An evaluation of the suitability of ERTS data for the purposes of petroleum exploration. [lithology and geological structure of Anadarko Basin of Oklahoma and Texas

Science.gov (United States)

Collins, R. J. (Principal Investigator); Mccown, F. P.; Stonis, L. P.; Petzel, G. J.; Everett, J. R.

1974-01-01

The author has identified the following significant results. ERTS-1 data give exploration geologists a new perspective for looking at the earth. The data are excellent for interpreting regional lithologic and structural relationships and quickly directing attention to areas of greatest exploration interest. Information derived from ERTS data useful for petroleum exploration include: linear features, general lithologic distribution, identification of various anomalous features, some details of structures controlling hydrocarbon accumulation, overall structural relationships, and the regional context of the exploration province. Many anomalies (particularly geomorphic anomalies) correlate with known features of petroleum exploration interest. Linears interpreted from the imagery that were checked in the field correlate with fractures. Bands 5 and 7 and color composite imagery acquired during the periods of maximum and minimum vegetation vigor are best for geologic interpretation. Preliminary analysis indicates that use of ERTS imagery can substantially reduce the cost of petroleum exploration in relatively unexplored areas.

Remedial action plan and site design for stabilization of the inactive uranium mill tailings sites at Slick Rock, Colorado: Appendix B to Attachment 3, lithologic logs

International Nuclear Information System (INIS)

1994-03-01

This appendix contains the lithologic logs and monitor well construction information for the remedial action plan for uranium mill tailings sites at Slick Rock, CO. Data from each borehole is presented graphically and a stratigraphic description is given

Lithological discrimination of accretionary complex (Sivas, northern Turkey) using novel hybrid color composites and field data

Science.gov (United States)

Özkan, Mutlu; Çelik, Ömer Faruk; Özyavaş, Aziz

2018-02-01

One of the most appropriate approaches to better understand and interpret geologic evolution of an accretionary complex is to make a detailed geologic map. The fact that ophiolite sequences consist of various rock types may require a unique image processing method to map each ophiolite body. The accretionary complex in the study area is composed mainly of ophiolitic and metamorphic rocks along with epi-ophiolitic sedimentary rocks. This paper attempts to map the Late Cretaceous accretionary complex in detail in northern Sivas (within İzmir-Ankara-Erzincan Suture Zone in Turkey) by the analysis of all of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) bands and field study. The new two hybrid color composite images yield satisfactory results in delineating peridotite, gabbro, basalt, and epi-ophiolitic sedimentary rocks of the accretionary complex in the study area. While the first hybrid color composite image consists of one principle component (PC) and two band ratios (PC1, 3/4, 4/6 in the RGB), the PC5, the original ASTER band 4 and the 3/4 band ratio images were assigned to the RGB colors to generate the second hybrid color composite image. In addition to that, the spectral indices derived from the ASTER thermal infrared (TIR) bands discriminate clearly ultramafic, siliceous, and carbonate rocks from adjacent lithologies at a regional scale. Peridotites with varying degrees of serpentinization illustrated as a single color were best identified in the spectral indices map. Furthermore, the boundaries of ophiolitic rocks based on fieldwork were outlined in detail in some parts of the study area by superimposing the resultant maps of ASTER maps on Google Earth images of finer spatial resolution. Eventually, the encouraging geologic map generated by the image analysis of ASTER data strongly correlates with lithological boundaries from a field survey.

Aquifer geometry, lithology, and water levels in the Anza–Terwilliger area—2013, Riverside and San Diego Counties, California

Science.gov (United States)

Landon, Matthew K.; Morita, Andrew Y.; Nawikas, Joseph M.; Christensen, Allen H.; Faunt, Claudia C.; Langenheim, Victoria E.

2015-11-24

The population of the Anza–Terwilliger area relies solely on groundwater pumped from the alluvial deposits and surrounding bedrock formations for water supply. The size, characteristics, and current conditions of the aquifer system in the Anza–Terwilliger area are poorly understood, however. In response to these concerns, the U.S. Geological Survey, in cooperation with the High Country Conservancy and Rancho California Water District, undertook a study to (1) improve mapping of groundwater basin geometry and lithology and (2) to resume groundwater-level monitoring last done during 2004–07 in the Anza–Terwilliger area. 

Configuration of the mudstones, gray- and coffee-colored shale lithologic units, zones of silica and epidote, and their relation to the tectonics of the Cerro Prieto geothermal field

Energy Technology Data Exchange (ETDEWEB)

Cobo R, J.M.

1981-01-01

Based on well cuttings, five lithological units have been recognized within the area of what is now the Cerro Prieto geothermal field. These five units are described. Differences in origin, mineralogy, grading, color, compaction, etc., are shown.

Milankovitch-scale correlations between deeply buried microbial populations and biogenic ooze lithology

Science.gov (United States)

Aiello, I.W.; Bekins, B.A.

2010-01-01

The recent discoveries of large, active populations of microbes in the subseafloor of the world's oceans supports the impact of the deep biosphere biota on global biogeochemical cycles and raises important questions concerning the functioning of these extreme environments for life. These investigations demonstrated that subseafloor microbes are unevenly distributed and that cell abundances and metabolic activities are often independent from sediment depths, with increased prokaryotic activity at geochemical and/or sedimentary interfaces. In this study we demonstrate that microbial populations vary at the scale of individual beds in the biogenic oozes of a drill site in the eastern equatorial Pacific (Ocean Drilling Program Leg 201, Site 1226). We relate bedding-scale changes in biogenic ooze sediment composition to organic carbon (OC) and microbial cell concentrations using high-resolution color reflectance data as proxy for lithology. Our analyses demonstrate that microbial concentrations are an order of magnitude higher in the more organic-rich diatom oozes than in the nannofossil oozes. The variations mimic small-scale variations in diatom abundance and OC, indicating that the modern distribution of microbial biomass is ultimately controlled by Milankovitch-frequency variations in past oceanographic conditions. ?? 2010 Geological Society of America.

Water retention and availability in soils of the State of Santa Catarina-Brazil: effect of textural classes, soil classes and lithology

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André da Costa

2013-12-01

Full Text Available The retention and availability of water in the soil vary according to the soil characteristics and determine plant growth. Thus, the aim of this study was to evaluate water retention and availability in the soils of the State of Santa Catarina, Brazil, according to the textural class, soil class and lithology. The surface and subsurface horizons of 44 profiles were sampled in different regions of the State and different cover crops to determine field capacity, permanent wilting point, available water content, particle size, and organic matter content. Water retention and availability between the horizons were compared in a mixed model, considering the textural classes, the soil classes and lithology as fixed factors and profiles as random factors. It may be concluded that water retention is greater in silty or clayey soils and that the organic matter content is higher, especially in Humic Cambisols, Nitisols and Ferralsol developed from igneous or sedimentary rocks. Water availability is greater in loam-textured soils, with high organic matter content, especially in soils of humic character. It is lower in the sandy texture class, especially in Arenosols formed from recent alluvial deposits or in gravelly soils derived from granite. The greater water availability in the surface horizons, with more organic matter than in the subsurface layers, illustrates the importance of organic matter for water retention and availability.

Lithological architecture and petrography of the Mako Birimian greenstone belt, Kédougou-Kéniéba Inlier, eastern Senegal

Science.gov (United States)

Dabo, Moussa; Aïfa, Tahar; Gning, Ibrahima; Faye, Malick; Ba, Mamadou Fallou; Ngom, Papa Malick

2017-07-01

The new lithological and petrographic data obtained in the Mako sector are analyzed in the light of the geochemical data available in the literature. It consists of ultramaic, mafic rocks of tholeiitic affinities associated with intermediate and felsic rocks of calc-alkaline affinities and with intercalations of sedimentary rocks. The whole unit is intruded by Eburnean granitoids and affected by a greenschist to amphibolite facies metamorphism related to a high grade hydrothermalism. It consists of: (i) ultramafic rocks composed of a fractional crystallization succession of lherzolites, wehrlites and pyroxenites with mafic rock inclusions; (ii) layered, isotropic and pegmatitic metagabbros which gradually pass to metabasalts occur at the top; (iii) massive and in pillow metabasalts with locally tapered vesicles, completely or partially filled with quartzo-feldspathic minerals; (iv) quarzites locally overlying the mafic rocks and thus forming the top of the lower unit. This ultramafic-mafic lower unit presents a tholeiitic affinity near to the OIB or N-MORB. It represents the Mako Ophiolitic Complex (MOC), a lithospheric fragment of Birimian lithospheric crust. The upper unit is a mixed volcanic complex arranged in the tectonic corridors. From bottom to top it comprises the following: (i) andesitic, and (ii) rhyodacitic and rhyolitic lava flows and tuffs, respectively. They present a calc-alkaline affinity of the active margins. Three generations of Eburnean granitoids are recognized: (i) early (2215-2160 Ma); (ii) syn-tectonics (2150-2100 Ma) and post-tectonics (2090-2040 Ma). The lithological succession, geochemical and metamorphic characteristics of these units point to an ophiolitic supra-subduction zone.

Discrimination of Sedimentary Lithologies Through Unmixing of EO-1 Hyperion Data: Melville Island, Canadian High Arctic

Science.gov (United States)

Leverington, D. W.

2008-12-01

The use of remote-sensing techniques in the discrimination of rock and soil classes in northern regions can help support a diverse range of activities including environmental characterization, mineral exploration, and the study of Quaternary paleoenvironments. Images of low spectral resolution can commonly be used in the mapping of lithological classes possessing distinct spectral characteristics, but hyperspectral databases offer greater potential for discrimination of materials distinguished by more subtle reflectance properties. Orbiting sensors offer an especially flexible and cost-effective means for acquisition of data to workers unable to conduct airborne surveys. In an effort to better constrain the utility of hyperspectral datasets in northern research, this study undertook to investigate the effectiveness of EO-1 Hyperion data in the discrimination and mapping of surface classes at a study area on Melville Island, Nunavut. Bedrock units in the immediate study area consist of late-Paleozoic clastic and carbonate sequences of the Sverdrup Basin. Weathered and frost-shattered felsenmeer, predominantly taking the form of boulder- to pebble-sized clasts that have accumulated in place and that mantle parent bedrock units, is the most common surface material in the study area. Hyperion data were converted from at-sensor radiance to reflectance, and were then linearly unmixed on the basis of end-member spectra measured from field samples. Hyperion unmixing results effectively portray the general fractional cover of six end members, although the fraction images of several materials contain background values that in some areas overestimate surface exposure. The best separated end members include the snow, green vegetation, and red-weathering sandstone classes, whereas the classes most negatively affected by elevated fraction values include the mudstone, limestone, and 'other' sandstone classes. Local overestimates of fractional cover are likely related to the

Xenoliths from Bunyaruguru volcanic field: Some insights into lithology of East African Rift upper mantle

Science.gov (United States)

Muravyeva, N. S.; Senin, V. G.

2018-01-01

The mineral composition of mantle xenoliths from kamafugites of the Bunyaruguru volcanic field has been determined. The major and some trace elements (Si, Ti, Al, Fe, Mn, Mg, Ca, Na, K, Cr, Ni, Ba, Sr, La, Ce, Nd, Nb) has been analyzed in olivine, clinopyroxene, phlogopite, Cr-spinel, titanomagnetite, perovskite and carbonates of xenoliths and their host lavas. Bunyaruguru is one of three (Katwe-Kikorongo, Fort Portal and Bunyaruguru) volcanic fields included in the Toro-Ankole province located on the North end of the West Branch of the East African Rift. The xenoliths from three craters within the Bunyaruguru volcanic field revealed the different character of metasomatic alteration, reflecting the heterogeneity of the mantle on the kilometer scale. The most unusual finding was composite glimmerite-wehrlite xenolith from the crater Kazimiro, which contains the fresh primary high-Mg olivine with inclusions of Cr-spinel that had not been previously identified in this area. The different composition of phenocryst and xenolith minerals indicates that the studied xenoliths are not cumulus of enclosing magma, but the composition of xenoliths characterizes the lithology of the upper mantle of the area. The carbonate melt inclusions in olivine Fo90 demonstrate the existence of primary carbonatitic magmas in Bunyaruguru upper mantle. The results of texture and chemical investigation of the xenolith minerals indicate the time sequence of metasomatic alteration of Bunyaruguru upper mantle: MARID metasomatism at the first stage followed by carbonate metasomatism. The abundances of REE in perovskites from kamafugite are 2-4 times higher than similar values for xenolith. Therefore the kamafugite magma was been generated from a more enriched mantle source than the source of the xenoliths. The evaluation of P-T conditions formation of clinopyroxene xenolith revealed the range of pressure 20-65 kbar and the temperatures range 830-1040 °C. The pressure of clinopyroxene phenocryst

Lithological controls on gas hydrate saturation: Insights from signal classification of NMR downhole data

Science.gov (United States)

Bauer, Klaus; Kulenkampff, Johannes; Henninges, Jan; Spangenberg, Erik

2016-04-01

Nuclear magnetic resonance (NMR) downhole data are analyzed with a new strategy to study gas hydrate-bearing sediments in the Mackenzie Delta (NW Canada). NMR logging is a powerful tool to study geological reservoir formations. The measurements are based on interactions between the magnetic moments of protons in geological formation water and an external magnetic field. Inversion of the measured raw data provides so-called transverse relaxation time (T2) distribution curves or spectra. Different parts of the T2 curve are related with distinct pore radii and corresponding fluid components. A common practice in the analysis of T2 distribution curves is to extract single-valued parameters such as apparent total porosity. Moreover, the derived total NMR apparent porosity and the gamma-gamma density log apparent porosity can be combined to estimate gas hydrate saturation in hydrate-bearing sediments. To avoid potential loss of information, in our new approach we analyze the entire T2 distribution curves as quasi-continuous signals to characterize the rock formation. The approach is applied to NMR data measured in gas hydrate research well Mallik 5L-38. We use self-organizing maps, a neural network clustering technique, to subdivide the data set of NMR T2 distribution curves into classes with a similar and distinctive signal shape. The method includes (1) preparation of data vectors, (2) unsupervised learning, (3) cluster definition, and (4) classification and depth mapping of all NMR signals. Each signal class thus represents a specific pore size distribution which can be interpreted in terms of distinct lithologies and reservoir types. A key step in the interpretation strategy is to reconcile the NMR classes with other log data not considered in the clustering analysis, such as gamma ray, photo-electric factor, hydrate saturation, and other logs. Our results defined six main lithologies within the target zone. Gas hydrate layers were recognized by their low signal

Comparison of lithological mapping results from airborne hyperspectral VNIR-SWIR, LWIR and combined data

Science.gov (United States)

Feng, Jilu; Rogge, Derek; Rivard, Benoit

2018-02-01

This study investigates using the Airborne Hyperspectral Imaging Systems (AISA) visible and short-wave infrared (SWIR) and Spatially Enhanced Broadband Array Spectrograph System (SEBASS) longwave infrared (LWIR) (2 and 4 m spatial resolution, respectively) imagery independently and in combination to produce detailed lithologic maps in a subarctic region (Cape Smith Belt, Nunavik, Canada) where regionally metamorphosed lower greenschist mafic, ultramafic and sedimentary rocks are exposed in the presence of lichen coatings. We make use of continuous wavelet analysis (CWA) to improve the radiometric quality of the imagery through the minimization of random noise and the enhancement of spectral features, the minimization of residual errors in the ISAC radiometric correction and target temperature estimation in the case of the LWIR data, the minimization of line to line residual calibration effects that lead to inconsistencies in data mosaics, and the reduction in variability of the spectral continuum introduced by variable illumination and topography. The use of CWA also provides a platform to directly combine the wavelet scale spectral profiles of the SWIR and LWIR after applying a scalar correction factor to the LWIR such that the dynamic range of two data sets have equal weight. This is possible using CWA as the datasets are normalized to a zero mean allowing spectra from different spectral regions to be adjoined. Lithologic maps are generated using an iterative spectral unmixing approach with image spectral endmembers extracted from the SWIR and LWIR imagery based on locations defined from previous work of the study area and field mapping information. Unmixing results of the independent SWIR and LWIR data, and the combined data show clear benefits to using the CWA combined imagery. The analysis showed SWIR and LWIR imagery highlight similar regions and spatial distributions for the three ultramafic units (dunite, peridotite, pyroxenite). However, significant

The effect of lithology on valley width, terrace distribution, and coarse sediment provenance in a tectonically stable catchment with flat-lying stratigraphy

Science.gov (United States)

Amanda Keen-Zebert,; Hudson, Mark R.; Stephanie L. Shepherd,; Evan A. Thaler,

2017-01-01

How rock resistance or erodibility affects fluvial landforms and processes is an outstanding question in geomorphology that has recently garnered attention owing to the recognition that the erosion rates of bedrock channels largely set the pace of landscape evolution. In this work, we evaluate valley width, terrace distribution, and sediment provenance in terms of reach scale variation in lithology in the study reach and discuss the implications for landscape evolution in a catchment with relatively flat2

Lithologic combinations in Romanesque churches of Álava, northern Spain

Directory of Open Access Journals (Sweden)

Martínez-Torres, L. M.

2014-03-01

Full Text Available Certain windows and doorways on twenty five Romanesque churches of Álava (XII–XIII centuries were built using six types of rock in nine different combinations. These compositions were intended to highlight the contrast in colour between different rocks, from which it can be deduced that the openings were not hewn to be painted. After almost seven centuries during which the use of stone was anecdotal, Romanesque artists burst in with colourful blends, demonstrating a broad knowledge of the characteristics of each rock and its availability. The uniqueness of these openings is represented on lithologic maps which, in addition to facilitating its analysis and dissemination, serve as a reference in its restoration.Algunas ventanas y portadas de veinticinco iglesias románicas de Álava (siglos XII-XIII fueron construidas con hasta seis tipos de rocas en nueve combinaciones diferentes. Estas composiciones pretendían resaltar el contraste cromático entre rocas distintas, de lo que se deduce que los vanos no fueron tallados para ser policromados. Después de casi siete siglos en los que el uso de la piedra fuera anecdótico, los artistas románicos irrumpen con mezclas coloristas, mostrando un amplio conocimiento de las características de cada roca y su disponibilidad. La singularidad de estos vanos está representada en mapas litológicos que, además de facilitar su análisis y divulgación, servirán de referencia en su restauración

Soil chemistry in lithologically diverse datasets: the quartz dilution effect

Science.gov (United States)

Bern, Carleton R.

2009-01-01

National- and continental-scale soil geochemical datasets are likely to move our understanding of broad soil geochemistry patterns forward significantly. Patterns of chemistry and mineralogy delineated from these datasets are strongly influenced by the composition of the soil parent material, which itself is largely a function of lithology and particle size sorting. Such controls present a challenge by obscuring subtler patterns arising from subsequent pedogenic processes. Here the effect of quartz concentration is examined in moist-climate soils from a pilot dataset of the North American Soil Geochemical Landscapes Project. Due to variable and high quartz contents (6.2–81.7 wt.%), and its residual and inert nature in soil, quartz is demonstrated to influence broad patterns in soil chemistry. A dilution effect is observed whereby concentrations of various elements are significantly and strongly negatively correlated with quartz. Quartz content drives artificial positive correlations between concentrations of some elements and obscures negative correlations between others. Unadjusted soil data show the highly mobile base cations Ca, Mg, and Na to be often strongly positively correlated with intermediately mobile Al or Fe, and generally uncorrelated with the relatively immobile high-field-strength elements (HFS) Ti and Nb. Both patterns are contrary to broad expectations for soils being weathered and leached. After transforming bulk soil chemistry to a quartz-free basis, the base cations are generally uncorrelated with Al and Fe, and negative correlations generally emerge with the HFS elements. Quartz-free element data may be a useful tool for elucidating patterns of weathering or parent-material chemistry in large soil datasets.

Lithological and Hydrothermal Alteration Mapping of Epithermal, Porphyry and Tourmaline Breccia Districts in the Argentine Andes Using ASTER Imagery

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Francisco J. Testa

2018-01-01

Full Text Available The area of interest is located on the eastern flank of the Andean Cordillera, San Juan province, Argentina. The 3600 km2 area is characterized by Siluro-Devonian to Neogene sedimentary and igneous rocks and unconsolidated Quaternary sediments. Epithermal, porphyry-related, and magmatic-hydrothermal breccia-hosted ore deposits, common in this part of the Frontal Cordillera, are associated with various types of hydrothermal alteration assemblages. Kaolinite – alunite-rich argillic, quartz – illite-rich phyllic, epidote – chlorite – calcite-rich propylitic and silicic are the most common hydrothermal alteration assemblages in the study area. VNIR, SWIR and TIR ASTER data were used to characterize geological features on a portion of the Frontal Cordillera. Red-green-blue band combinations, band ratios, logical operations, mineral indices and principal component analysis were applied to successfully identify rock types and hydrothermal alteration zones in the study area. These techniques were used to enhance geological features to contrast different lithologies and zones with high concentrations of argillic, phyllic, propylitic alteration mineral assemblages and silicic altered rocks. Alteration minerals detected with portable short-wave infrared spectrometry in hand specimens confirmed the capability of ASTER to identify hydrothermal alteration assemblages. The results from field control areas confirmed the presence of those minerals in the areas classified by ASTER processing techniques and allowed mapping the same mineralogy where pixels had similar information. The current study proved ASTER processing techniques to be valuable mapping tools for geological reconnaissance of a large area of the Argentinean Frontal Cordillera, providing preliminary lithologic and hydrothermal alteration maps that are accurate as well as cost and time effective.

Effluent migration from septic tank systems in two different lithologies, Broward County, Florida

Science.gov (United States)

Waller, B.G.; Howie, Barbara; Causaras, C.R.

1987-01-01

Two septic tank test sites, one in sand and one in limestone, in Broward County, Florida, were analyzed for effluent migration. Groundwater from shallow wells, both in background areas and hydraulically down-gradient of the septic tank system, was sampled during a 16-month period from April 1983 through August 1984. Water quality indicators were used to determine the effluent affected zone near the septic tank systems. Specific conductance levels and concentrations of chloride, sulfate, ammonium, and nitrate indicated effluent movement primarily in a vertical direction with abrupt dilution as it moved down-gradient. Effluent was detected in the sand to a depth more than 20 ft below the septic tank outlet, but was diluted to near background conditions 50 ft down-gradient from the tank. Effluent in the limestone was detected in all three observation wells to depths exceeding 25 ft below the septic tank outlet and was diluted, but still detectable, 40 ft down-gradient. The primary controls on effluent movement from septic tank systems in Broward County are the lithology and layering of the geologic materials, hydraulic gradients, and the volume and type of use the system receives. (Author 's abstract)

HCMM: Soil moisture in relation to geologic structure and lithology, northern California. [Northern Coast Range, Sacramento Valley, and the Modoc Plateau

Science.gov (United States)

Rich, E. I. (Principal Investigator)

1981-01-01

Heat capacity mapping mission images of about 80,000 sq km in northern California were qualitatively evaluated for usefulness in regional geologic investigations of structure and lithology. The thermal characteristics recorded vary among the several geomorphic provinces and depend chiefly on the topographic expression and vegetation cover. Identification of rock types, or groups of rock types, was most successfully carried out within the semiarid parts of the region; however, extensive features, such as faults, folds and volcanic fields could be delineated. Comparisons of seasonally obtained HCMM images are of limited value except in semiarid regions.

spMC: an R-package for 3D lithological reconstructions based on spatial Markov chains

Science.gov (United States)

Sartore, Luca; Fabbri, Paolo; Gaetan, Carlo

2016-09-01

The paper presents the spatial Markov Chains (spMC) R-package and a case study of subsoil simulation/prediction located in a plain site of Northeastern Italy. spMC is a quite complete collection of advanced methods for data inspection, besides spMC implements Markov Chain models to estimate experimental transition probabilities of categorical lithological data. Furthermore, simulation methods based on most known prediction methods (as indicator Kriging and CoKriging) were implemented in spMC package. Moreover, other more advanced methods are available for simulations, e.g. path methods and Bayesian procedures, that exploit the maximum entropy. Since the spMC package was developed for intensive geostatistical computations, part of the code is implemented for parallel computations via the OpenMP constructs. A final analysis of this computational efficiency compares the simulation/prediction algorithms by using different numbers of CPU cores, and considering the example data set of the case study included in the package.

Dust deposition in southern Nevada and California, 1984-1989: Relations to climate, source area, and source lithology

Science.gov (United States)

Reheis, Marith C.; Kihl, Rolf

1995-05-01

Dust samples collected annually for 5 years from 55 sites in southern Nevada and California provide the first regional source of information on modern rates of dust deposition, grain size, and mineralogical and chemical composition relative to climate and to type and lithology of dust source. The average silt and clay flux (rate of deposition) in southern Nevada and southeastern California ranges from 4.3 to 15.7 g/m2/yr, but in southwestern California the average silt and clay flux is as high as 30 g/m2/yr. The climatic factors that affect dust flux interact with each other and with the factors of source type (playas versus alluvium), source lithology, geographic area, and human disturbance. Average dust flux increases with mean annual temperature but is not correlated to decreases in mean annual precipitation because the regional winds bring dust to relatively wet areas. In contrast, annual dust flux mostly reflects changes in annual precipitation (relative drought) rather than temperature. Although playa and alluvial sources produce about the same amount of dust per unit area, the total volume of dust from the more extensive alluvial sources is much larger. In addition, playa and alluvial sources respond differently to annual changes in precipitation. Most playas produce dust that is richer in soluble salts and carbonate than that from alluvial sources (except carbonate-rich alluvium). Gypsum dust may be produced by the interaction of carbonate dust and anthropogenic or marine sulfates. The dust flux in an arid urbanizing area may be as much as twice that before disturbance but decreases when construction stops. The mineralogic and major-oxide composition of the dust samples indicates that sand and some silt is locally derived and deposited, whereas clay and some silt from different sources can be far-traveled. Dust deposited in the Transverse Ranges of California by the Santa Ana winds appears to be mainly derived from sources to the north and east.

Lithological indicators of loess sedimentation of SW Poland

Directory of Open Access Journals (Sweden)

Krawczyk Marcin

2017-12-01

Full Text Available High-resolution grain-size investigations were carried out in two SW Polish loess sections: Biały Kościół (Niemcza-Strzelin Hills and Zaprężyn (Trzebnica Hills. Each sequence was sampled by using the same methodology and samples were taken at 5 centimeters intervals. The particle size distribution was obtained with a Mastersizer 2000 laser, used for diffraction methods. From the obtained results the basic parameters and grain size indicators were calculated: Mz, Grain Size Index ratio, U-ratio and the percentage content of clay ( 63 μm. Both loess-soil sequences are composed of interfluve and slope loess facies and consist of five litho-pedostratigraphic units developed during the Late Pleistocene and Holocene: two loess units L1LL1, L1LL2 and three polygenetic fossil soils sets S0, S1 and L1SS1. The distance between these two profiles is about 60 km. Zaprężyn, as a section located more to the north, has almost no lower younger loess and higher level of weathering which could be related to proximity of this site to the Ice Sheet margin. The climate here was more extreme and harsh. What is more, the difference in development of soil L1SS1 can be observed: while in Biały Kościół pedogenesis process was slower and less disturbed than in Zaprężyn. The upper part of L1SS1 in Biały Kościół was deformed by gelifluction, frost heave and other periglacial processes. Mz indicator by the grain-size distribution in these sediments reflects subtle variations in the climatic system. Moreover, in Zaprężyn the content of sand fraction is higher than in Biały Kościół what can be the evidence of short episodes of strong winds during cold period of sedimentation. The aim of this paper is to compare two loess profiles by their stratigraphical and lithological similarities which are result of climate conditions and features of surrounding environment.

Gamma-gamma density and lithology tools simulation based on GEANT4 advanced low energy Compton scattering (GALECS) package

International Nuclear Information System (INIS)

Esmaeili-sani, Vahid; Moussavi-zarandi, Ali; Boghrati, Behzad; Afarideh, Hossein

2012-01-01

Geophysical bore-hole data represent the physical properties of rocks, such as density and formation lithology, as a function of depth in a well. Properties of rocks are obtained from gamma ray transport logs. Transport of gamma rays, from a 137 Cs point gamma source situated in a bore-hole tool, through rock media to detectors, has been simulated using a GEANT4 radiation transport code. The advanced Compton scattering concepts were used to gain better analyses about well formation. The simulation and understanding of advanced Compton scattering highly depends on how accurately the effects of Doppler broadening and Rayleigh scattering are taken into account. A Monte Carlo package that simulates the gamma-gamma well logging tools based on GEANT4 advanced low energy Compton scattering (GALECS).

Sensitivity of the hypsometric integral (HI and its connections with lithology and neotectonics in the Rodna Mountains, Romanian Carpathians

Directory of Open Access Journals (Sweden)

Andrei ZAMOSTEANU

2015-10-01

Full Text Available This study investigates the sensitivity of the hypsometric integral (HI and its connections with lithology and neotectonics from northern Romanian Carpathians, Rodna Mountains. Two types of DEM was used in analysis (a 30m DEM resolution with specific grid size and a non-gridded 30m DEM resolution. Several methods have been applied in order to calculate HI as: the CalHypso GIS extension was used to automatically extract multiple hypsometric curves from digital elevation model (DEM and to calculate the main statistics related to the HI by applying polynomial fits; local indices of spatial autocorrelation were applied using Anselin Local Moran’s I and Getis-Ord Gi* in order to see if HI distribution has spatial patterns values and selection of valid squares (500m2 grid using 30m DEM using ArcMap 10.1 for the lithological analysis. The values of the hypsometric kurtosis density, kurtosis, skew and density skew are increasing eastwards. Values of hypsometric skewness for the northern slope are in range between 0.290 – 0.816 and sowthern part between 0.414 – 0.507. The results show that HI values are higher than 0.5 in the areas with recent tectonic influences especially in northern part near Dragoş Vodă fault system. The formations with a Oligocene, Miocene, Pleistocene and Holocene age have low values (<0.5 wile the other ones from Precambrian, Cambrian, Silurian, Eocene, Miocene and Pliocene age have higher values (>0.5. Comparing HI values from these two analysis (500m grid size DEM and the DEM without grid size of the DEM we find some slightly differences in HI values specially in the northern part of the range on Repedea, Negoiescu Mare, Fântâna and Lala basins

Geological and petrophysical characterization of the Ferron Sandstone for 3-D simulation of a fluvial-deltaic reservoir. Deliverable 2.5.4, Ferron Sandstone lithologic strip logs, Emergy & Sevier Counties, Utah: Volume I

Energy Technology Data Exchange (ETDEWEB)

Allison, M.L.

1995-12-08

Strip logs for 491 wells were produced from a digital subsurface database of lithologic descriptions of the Ferron Sandstone Member of the Mancos Shale. This subsurface database covers wells from the parts of Emery and Sevier Counties in central Utah that occur between Ferron Creek on the north and Last Chance Creek on the south. The lithologic descriptions were imported into a logging software application designed for the display of stratigraphic data. Strip logs were produced at a scale of one inch equals 20 feet. The strip logs were created as part of a study by the Utah Geological Survey to develop a comprehensive, interdisciplinary, and qualitative characterization of a fluvial-deltaic reservoir using the Ferron Sandstone as a surface analogue. The study was funded by the U.S. Department of Energy (DOE) under the Geoscience/Engineering Reservoir Characterization Program.

Gabbroic lithologies of the dike-gabbro transition, Hole GT3A, Oman Drilling Project

Science.gov (United States)

Jesus, A. P. M.; Koepke, J.; Morishita, T.; Beinlich, A.; Johnson, K. T. M.; Greenberger, R. N.; Harris, M.; Michibayashi, K.; de Obeso, J. C.

2017-12-01

Hole GT3A intersects 400 m of oceanic crust providing unique insight into the dike-gabbro transition and the variability of the high level gabbros in the Samail ophiolite. Olivine gabbro and olivine bearing gabbro occur exclusively within the Upper Gabbro Sequence (16 % thickness; 111.02 m - 127.89 m) whereas oxide gabbro and disseminated oxide gabbro represent ca 5 % of the Lower Gabbro Sequence (233.84 m - 398.21 m). Gabbro with less than 1 vol. % olivine and oxide is the most common lithology in both Gabbro Sequences (10-13 %). Most gabbroic rocks were classified as "varitextured" due to textural and grain size macroscopic variations forming irregular domains/patches. Varitextured gabbros are medium-grained (1-5 mm), with seriate grain size distribution and subophitic/poikilitic to granular textural domains. Poikilitic domains comprise clinopyroxene with plagioclase chadacrysts, whereas in granular domains plagioclase interstices are filled by green-brown magmatic hornblende; plagioclase is zoned in both domains. Olivine (bearing) gabbros have 4-8 mm skeletal olivine pseudomorphs with roundish inclusions of chromite and plagioclase. Oxide (disseminated) gabbros comprise variable amounts of plagioclase, clinopyroxene, Oman paleo ridge.

Gamma-gamma density and lithology tools simulation based on GEANT4 advanced low energy Compton scattering (GALECS) package

Energy Technology Data Exchange (ETDEWEB)

Esmaeili-sani, Vahid, E-mail: vaheed_esmaeely80@yahoo.com [Department of Nuclear Engineering and Physics, Amirkabir University of Technology, P.O. Box 4155-4494, Tehran (Iran, Islamic Republic of); Moussavi-zarandi, Ali; Boghrati, Behzad; Afarideh, Hossein [Department of Nuclear Engineering and Physics, Amirkabir University of Technology, P.O. Box 4155-4494, Tehran (Iran, Islamic Republic of)

2012-02-01

Geophysical bore-hole data represent the physical properties of rocks, such as density and formation lithology, as a function of depth in a well. Properties of rocks are obtained from gamma ray transport logs. Transport of gamma rays, from a {sup 137}Cs point gamma source situated in a bore-hole tool, through rock media to detectors, has been simulated using a GEANT4 radiation transport code. The advanced Compton scattering concepts were used to gain better analyses about well formation. The simulation and understanding of advanced Compton scattering highly depends on how accurately the effects of Doppler broadening and Rayleigh scattering are taken into account. A Monte Carlo package that simulates the gamma-gamma well logging tools based on GEANT4 advanced low energy Compton scattering (GALECS).

Influence of lithological characters of coal bearing formation on stability of roof of coal seams

Energy Technology Data Exchange (ETDEWEB)

Meng Zhao-ping; Peng Su-ping; Li Guo-qing; Huang Wei; Lu Jun; Lei Zhi-yong [CUMT, Beijing (China). School of Resources and Safety Engineering

2003-07-01

Lithology is one of the important factors influencing the stability of roof of coal seams. In order to investigate this, the phenomenon of underground pressure and distribution of pressure were studied by using the local observation and simulation test with similar materials. The observation results show that the distance of initial weighting and periodic weighting of the mudstone roof is shorter than that of sandstone roofs. The sandstone roof with a high strength has a longer distance of initial weighting and periodic weighting, the abutment stress on the working face is big and the height of caving and fracture zone is high. The peak point of abutment stress in the sandstone roof is near to the working face and the pressure bump is inclined to occur. The result is contrary to that in case of the mudstone roof with a low strength. While in the transition zone of nipped sandstone, roof rock-mass is broken and is poor in stability, therefore, it is difficult to hold the roof.

Inferring the lithology of borehole rocks by applying neural network classifiers to downhole logs: an example from the Ocean Drilling Program

Science.gov (United States)

Benaouda, D.; Wadge, G.; Whitmarsh, R. B.; Rothwell, R. G.; MacLeod, C.

1999-02-01

In boreholes with partial or no core recovery, interpretations of lithology in the remainder of the hole are routinely attempted using data from downhole geophysical sensors. We present a practical neural net-based technique that greatly enhances lithological interpretation in holes with partial core recovery by using downhole data to train classifiers to give a global classification scheme for those parts of the borehole for which no core was retrieved. We describe the system and its underlying methods of data exploration, selection and classification, and present a typical example of the system in use. Although the technique is equally applicable to oil industry boreholes, we apply it here to an Ocean Drilling Program (ODP) borehole (Hole 792E, Izu-Bonin forearc, a mixture of volcaniclastic sandstones, conglomerates and claystones). The quantitative benefits of quality-control measures and different subsampling strategies are shown. Direct comparisons between a number of discriminant analysis methods and the use of neural networks with back-propagation of error are presented. The neural networks perform better than the discriminant analysis techniques both in terms of performance rates with test data sets (2-3 per cent better) and in qualitative correlation with non-depth-matched core. We illustrate with the Hole 792E data how vital it is to have a system that permits the number and membership of training classes to be changed as analysis proceeds. The initial classification for Hole 792E evolved from a five-class to a three-class and then to a four-class scheme with resultant classification performance rates for the back-propagation neural network method of 83, 84 and 93 per cent respectively.

Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Sites at Slick Rock, Colorado: Appendix B to Attachment 3, Lithologic logs and monitor well construction information. Final report

International Nuclear Information System (INIS)

1995-09-01

This volume contains lithology logs and monitor well construction information for: NC processing site; UC processing site; and Burro Canyon disposal site. This information pertains to the ground water hydrology investigations which is attachment 3 of this series of reports

Lithology and temperature: How key mantle variables control rift volcanism

Science.gov (United States)

Shorttle, O.; Hoggard, M.; Matthews, S.; Maclennan, J.

2015-12-01

Continental rifting is often associated with extensive magmatic activity, emplacing millions of cubic kilometres of basalt and triggering environmental change. The lasting geological record of this volcanic catastrophism are the large igneous provinces found at the margins of many continents and abrupt extinctions in the fossil record, most strikingly that found at the Permo-Triassic boundary. Rather than being considered purely a passive plate tectonic phenomenon, these episodes are frequently explained by the involvement of mantle plumes, upwellings of mantle rock made buoyant by their high temperatures. However, there has been debate over the relative role of the mantle's temperature and composition in generating the large volumes of magma involved in rift and intra-plate volcanism, and even when the mantle is inferred to be hot, this has been variously attributed to mantle plumes or continental insulation effects. To help resolve these uncertainties we have combined geochemical, geophysical and modelling results in a two stage approach: Firstly, we have investigated how mantle composition and temperature contribute to melting beneath Iceland, the present day manifestation of the mantle plume implicated in the 54Ma break up of the North Atlantic. By considering both the igneous crustal production on Iceland and the chemistry of its basalts we have been able to place stringent constraints on the viable temperature and lithology of the Icelandic mantle. Although a >100°C excess temperature is required to generate Iceland's thick igneous crust, geochemistry also indicates that pyroxenite comprises 10% of its source. Therefore, the dynamics of rifting on Iceland are modulated both by thermal and compositional mantle anomalies. Secondly, we have performed a global assessment of the mantle's post break-up thermal history to determine the amplitude and longevity of continental insulation in driving excess volcanism. Using seismically constrained igneous crustal

Subsurface imaging of water electrical conductivity, hydraulic permeability and lithology at contaminated sites by induced polarization

Science.gov (United States)

Maurya, P. K.; Balbarini, N.; Møller, I.; Rønde, V.; Christiansen, A. V.; Bjerg, P. L.; Auken, E.; Fiandaca, G.

2018-05-01

At contaminated sites, knowledge about geology and hydraulic properties of the subsurface and extent of the contamination is needed for assessing the risk and for designing potential site remediation. In this study, we have developed a new approach for characterizing contaminated sites through time-domain spectral induced polarization. The new approach is based on: (1) spectral inversion of the induced polarization data through a reparametrization of the Cole-Cole model, which disentangles the electrolytic bulk conductivity from the surface conductivity for delineating the contamination plume; (2) estimation of hydraulic permeability directly from the inverted parameters using a laboratory-derived empirical equation without any calibration; (3) the use of the geophysical imaging results for supporting the geological modelling and planning of drilling campaigns. The new approach was tested on a data set from the Grindsted stream (Denmark), where contaminated groundwater from a factory site discharges to the stream. Two overlapping areas were covered with seven parallel 2-D profiles each, one large area of 410 m × 90 m (5 m electrode spacing) and one detailed area of 126 m × 42 m (2 m electrode spacing). The geophysical results were complemented and validated by an extensive set of hydrologic and geologic information, including 94 estimates of hydraulic permeability obtained from slug tests and grain size analyses, 89 measurements of water electrical conductivity in groundwater, and four geological logs. On average the IP-derived and measured permeability values agreed within one order of magnitude, except for those close to boundaries between lithological layers (e.g. between sand and clay), where mismatches occurred due to the lack of vertical resolution in the geophysical imaging. An average formation factor was estimated from the correlation between the imaged bulk conductivity values and the water conductivity values measured in groundwater, in order to

Defining in-situ stress magnitude and the responses of geology to stress anisotropy in heterogeneous lithologies for the United Kingdom

Science.gov (United States)

Kingdon, A.; Fellgett, M. W.; Williams, J. D. O.

2017-12-01

Exploitation of shale gas in the USA has led to interest in similar UK deposits. After tremors at the Preese Hall well in 2011, the process of hydraulic fracturing has become contentious. In-situ stress orientation controls the direction that fractures propagate from a well. World Stress Map (WSM) data coverage for the UK has historically been sparse. Improvements to the stress orientations for the UK are vital for reducing risk levels of induced seismicity. In some offshore basins, maximum horizontal stress (SHMax) is sub-parallel to major inverted Permo-Triassic faults, episodically reactivated during the Cenozoic, indicating a degree of structural control. Understanding for UK stress magnitude has been poor. Data for Northern England has been augmented with new estimates of vertical stress (Sv), minimum horizontal stress (Shmin) and pore pressure, focussed on potentially prospective basins east and west of the Pennines. Calculated values combined with legacy hydraulic fracturing and overcoring data show vertical stress gradients vary from 23 to 26 MPa/Km-1. Cheshire and Scotland show higher Shmin values by 2 MPa/Km-1 compared to Yorkshire and South East England. SHMax values exceeds the Sv which in turn exceeds Shmin indicating a predominantly strike slip environment. Pore pressure appears to be uniformly hydrostatic across the studied regions. There is some evidence above 1200 m depth of reverse faulting in igneous rocks in Cornwall, Leicestershire and Cumbria. Analysis of borehole imaging for the lithologically heterogeneous Carboniferous Coal Measures, highlights variability failure modes over confined vertical intervals. Breakouts are disproportionately located in "seatearths", palaeosols located stratigraphically beneath coal seams. Drilling induced tensile fractures are located within close proximity in overbank silt/clay facies and relatively massive channel sands that typically over and underlie coal deposits. Strength tests show that breakouts occur in

Cyclostratigraphic analysis of the Middle to lower Upper Ordovician Postolonnec Formation in the Armorican Massif (France): integrating pXRF, gammay-ray and lithological data

Science.gov (United States)

Sinnesael, Matthias; Loi, Alfredo; Dabard, Marie-Pierre; Vandenbroucke, Thijs; Claeys, Philippe

2017-04-01

The Middle to lower Upper Ordovician sections of the Crozon Peninsula area (Postolonnec Formation, Armorican Massif, western France) show multi-order eustatic sea-level changes (Dabard et al., 2015). The sections are characterized by siliciclastic facies, which were deposited in tidal to storm-dominated shelf environments. Dabard et al. (2015) analysed the facies, their stacking patterns, and gamma-ray data and applied backstripping to identify subsidence and several orders of sea-level change. The main stratigraphic constraints are coming from (chitinozoan) biostratigraphy. The 3th to 5th orders changes are hypothesized to correspond to various frequencies related to astronomical forcing. This study investigates the potential added value of portable X-Ray Fluorescence (pXRF) and the application of spectral analyses. High-resolution (cm-scale) non-destructive pXRF and natural gamma-ray measurements were carried out on 14 m of section that was equally logged on a cm resolution. The pXRF measurements on the surface of the outcrops are compared with earlier results of wavelength dispersive XRF spectrometry and ICP-MS. The potassium records of the pXRF and gamma-ray logs are comparable and essentially reflect lithological variations (i.e., between mudstone and coarse sandstones). Other reliably measured elements also reflected lithological aspects such as clay-sandstone alternations (e.g. K, Rb, Ti), placer locations (Zr, Ce, Ti) and potentially clay mineralogy and condensation horizons (Ni, Zn, Co, Mn). Spectral analyses of the various proxies (lithology, natural gamma-ray and pXRF) are compared with each other. Both the new high-resolution data (14 m of section) as well as the published low-resolution data (which span almost 400 m of Darriwilian-Sandbian) were analyzed. The study reveals strong indications for the imprint of obliquity, precession and eccentricity. Obtaining age constraints, in addition to the existing biostratigraphical framework is a challenge in

Lithologic Coring in the Lower Anacostia Tidal Watershed, Washington, D.C., July 2002

Science.gov (United States)

Tenbus, Frederick J.

2003-01-01

Little is known about the volumetric flux of ground water to the lower tidal Anacostia River, or whether ground-water flow is an important component of the contaminant load in this part of the Anacostia River. The watershed is in the eastern part of Washington, D.C., and has been subjected to over 200 years of urbanization and modifications of the river channel and nearby land areas. These anthropogenic factors, along with tidal fluctuations in the river, make ground-water data collection and interpretations difficult. The U.S. Geological Survey is cooperating with the District of Columbia Department of Health, Environmental Health Administration, Bureau of Environmental Quality, Water Quality Division, in a study to assess nonpoint-source pollution from ground water into the lower tidal Anacostia River. Lithologic cores from drilling activities conducted during July 2002 in the study area have been interpreted in the context of geologic and hydrogeologic information from previous studies in the lower Anacostia tidal watershed. These interpretations can help achieve the overall project goals of characterizing ground-water flow and contaminant load in the study area. Hydrostratigraphic units encountered during drilling generally consisted of late Pleistocene to Holocene fluvial deposits overlying Cretaceous fluvial/deltaic deposits. Cores collected in Beaverdam Creek and the Anacostia River indicated high- and low-energy environments of deposition, respectively. Two cores collected near the river showed different types of anthropogenic fill underlain by low-energy deposits, which were in turn underlain by sand and gravel. A third core collected near the river consisted primarily of sand and gravel with no artificial fill.

Microbial reduction of uranium(VI) in sediments of different lithologies collected from Sellafield

International Nuclear Information System (INIS)

Newsome, Laura; Morris, Katherine; Trivedi, Divyesh; Atherton, Nick; Lloyd, Jonathan R.

2014-01-01

Highlights: • U(VI) (aq) mobility can be controlled by stimulating biogeochemical interactions. • Indigenous microbes in varied sediments reduced U(VI) to insoluble U(IV). • Sediment cell numbers and amount of bioavailable Fe(III) could limit this process. - Abstract: The presence of uranium in groundwater at nuclear sites can be controlled by microbial processes. Here we describe the results from stimulating microbial reduction of U(VI) in sediment samples obtained from a nuclear-licensed site in the UK. A variety of different lithology sediments were selected to represent the heterogeneity of the subsurface at a site underlain by glacial outwash deposits and sandstone. The natural sediment microbial communities were stimulated via the addition of an acetate/lactate electron donor mix and were monitored for changes in geochemistry and molecular ecology. Most sediments facilitated the removal of 12 ppm U(VI) during the onset of Fe(III)-reducing conditions; this was reflected by an increase in the proportion of known Fe(III)- and U(VI)-reducing species. However U(VI) remained in solution in two sediments and Fe(III)-reducing conditions did not develop. Sequential extractions, addition of an Fe(III)-enrichment culture and most probable number enumerations revealed that a lack of bioavailable iron or low cell numbers of Fe(III)-reducing bacteria may be responsible. These results highlight the potential for stimulation of microbial U(VI)-reduction to be used as a bioremediation strategy at UK nuclear sites, and they emphasise the importance of both site-specific and borehole-specific investigations to be completed prior to implementation

Strain localization in the lower crust: brittle precursors versus lithological heterogeneities (Musgrave Ranges, Central Australia)

Science.gov (United States)

Hawemann, Friedrich; Mancktelow, Neil; Wex, Sebastian; Pennacchioni, Giorgio; Camacho, Alfredo

2016-04-01

The Davenport shear zone in Central Australia is a strike-slip ductile shear zone developed during the Petermann Orogeny (~ 550 Ma). The conditions of shearing are estimated to be amphibolite-eclogite facies (650 °C, 1.2 GPa). The up to seven kilometre thick mylonite zone encloses several large low strain domains with excellent exposure, thus allowing a thorough study of the initiation of shear zones. Quartzo-feldspathic gneisses and granitoids inherit a suite of lithological heterogeneities such as quartz-rich pegmatites, mafic layers and dykes. When in a favourable orientation to the shortening direction, these rheologically different pre-existing layers might be expected to localize deformation. However, with the singular exception of long, continuous and fine-grained dolerite dykes, this is not observed. Quartz-rich pegmatites are mostly unsheared, even if in a favourable orientation, and sometimes boudinaged or folded. There are instead many shear zones only a few mm to cm in width, extending up to tens of metres, which are in fact oriented at a very high angle to the shortening direction. Parallel to these, a network of little to moderately overprinted brittle fractures are observed, commonly marked by pseudotachylyte (pst) and sometimes new biotite. Shear reactivation of these precursor fractures is generally limited to the length of the initial fracture and typically re-uses and shears the pst. The recrystallized mineral assemblage in the sheared pst consists of Cpx+Grt+Fsp±Ky and is the same to that in the adjacent sheared gneiss, with the same PT estimates (650 °C, 1.2 GPa). In some cases, multiple generations of cross-cutting and sheared pst demonstrate alternating fracture and flow during progressive shear zone development and a clear tendency for subsequent pst formation to also localize in the existing shear zone. The latest pst may be both unsheared and unrecrystallized (no grt) and is probably related to a late stage, still localized within the

Monitoring electrical properties for improving the lithological and hydrological characterization of landslides

Science.gov (United States)

Malet, J. P.; Gance, J.; Lajaunie, M.; Gallistl, J.; Denchik, N.; Flores Orozco, A.; Ottowitz, D.; Supper, R.; Sailhac, P.; Gautier, S.; Schmutz, M.

2017-12-01

Imaging water flows in landslides is of critical importance as the distribution of pore-fluid pressures controls the dynamics (acceleration, deceleration) of the material. Detecting and imaging water is a difficult task, not only because of the complex topography and the small dimensions of the geological structures, but also because the landslide material consists of unsaturated porous and heterogeneous fractured media, leading to multi-scale water-flow properties. Further, these properties can change in time, in relation to temperature, rainfall and biological forcings. Electrical properties are relevant proxies of the sub-surface hydrological properties. In order to image water in landslide bodies, we propose to combine multi-frequency electrical and electromagnetic measurements using campaigns or permanent instruments, and surface/boreole investigations, installed on several unstable slopes in France. To evaluate the information gained from electrical properties for different geological conditions, we discuss electrical and electro-magnetic imaging results for data collected at four different landslides located in France (Super-Sauze and La Valette in the South East Alps, Lodève lin the southern border of the Massif Central Massif, and Séchilienne in the North French Alps). Time-lapse electrical DC resistivity observations, complex electrical conductivity (conduction and polarization/chargeability) measured by IP imaging methods, and controlled-source electromagnetic (CS-AMT) methods are discussed. Imaging results demonstrate an improved lithological characterization of the landslide structures (delineation of the sliding planes, identification of the fractures, discrimination of clay lenses with enhanced resolution); further, water infiltration within the soil matrix and/or the fractures is discriminated allowing better modelling of the hydrological regime of the landslides at the slope scale. This research is conducted in the frame of the project HYDROSLIDE

Spatial variations in fault friction related to lithology from rupture and afterslip of the 2014 South Napa, California, earthquake

Science.gov (United States)

Michael Floyd,; Richard Walters,; John Elliot,; Funning, Gareth J.; Svarc, Jerry L.; Murray, Jessica R.; Andy Hooper,; Yngvar Larsen,; Petar Marinkovic,; Bürgmann, Roland; Johanson, Ingrid; Tim Wright,

2016-01-01

Following earthquakes, faults are often observed to continue slipping aseismically. It has been proposed that this afterslip occurs on parts of the fault with rate-strengthening friction that are stressed by the mainshock, but our understanding has been limited by a lack of immediate, high-resolution observations. Here we show that the behavior of afterslip following the 2014 South Napa earthquake varied over distances of only a few kilometers. This variability cannot be explained by coseismic stress changes alone. We present daily positions from continuous and survey GPS sites that we re-measured within 12 hours of the mainshock, and surface displacements from the new Sentinel-1 radar mission. This unique geodetic data set constrains the distribution and evolution of coseismic and postseismic fault slip with exceptional resolution in space and time. We suggest that the observed heterogeneity in behavior is caused by lithological controls on the frictional properties of the fault plane.

Lithological Effects on Evaporation and Direct Infiltration Through the Unsaturated Zone in Damascus Oasis (Syria)

International Nuclear Information System (INIS)

Abou zakhem, B.

2004-01-01

Soil water movement is directly affected by the lithology and texture of soil profile. The objective of this study is to determine water movement mechanism through the unsaturated zone, by estimating the direct infiltration rate and evaporation process in Damascus Oasis, using isotope techniques. Two soil profiles were drilled using a hand-auger. Soil samples were subjected to granulometry, mineralogy, chemical and isotopic analysis. Isotopic measurements indicate that the evaporation front is located at shallow depth between 0 and 2 m. Variations in isotopic content indicate to the alternation of wet and dry periods corresponding to infiltration and evaporation processes respectively. Results show considerable difference in isotopic content between the unsaturated zone and the groundwater, which is mainly attributed to limited recharge of the aquifer through the unsaturated. Whereas the indirect groundwater recharge is considered to be more predominant. Chloride concentration correspond to stable isotopes in the unsaturated zone, it increases proportionally with the evaporation rate. Using chemical balance of Chloride, it was possible to estimate the effective recharge average rate which is ranging between 1.8 mm/y and 0.45 mm/y. The calculated mean evaporation rate according to Barnes and Allison model is 18.1 mm/y at water table level of 3 m depth. This rate decreases to 2.4 mm/y at 6 m depth. (author)

Sedimentary facies and lithologic characters as main factors controlling hydrocarbon accumulations and their critical conditions

Directory of Open Access Journals (Sweden)

Jun-Qing Chen

2015-10-01

Full Text Available Taking more than 1000 clastic hydrocarbon reservoirs of Bohai Bay Basin, Tarim Basin and Junggar Basin, China as examples, the paper has studied the main controlling factors of hydrocarbon reservoirs and their critical conditions to reveal the hydrocarbon distribution and to optimize the search for favorable targets. The results indicated that the various sedimentary facies and lithologic characters control the critical conditions of hydrocarbon accumulations, which shows that hydrocarbon is distributed mainly in sedimentary facies formed under conditions of a long-lived and relatively strong hydrodynamic environment; 95% of the hydrocarbon reservoirs and reserves in the three basins is distributed in siltstones, fine sandstones, lithified gravels and pebble-bearing sandstones; moreover, the probability of discovering conventional hydrocarbon reservoirs decreases with the grain size of the clastic rock. The main reason is that the low relative porosity and permeability of fine-grained reservoirs lead to small differences in capillary force compared with surrounding rocks small and insufficiency of dynamic force for hydrocarbon accumulation; the critical condition for hydrocarbon entering reservoir is that the interfacial potential in the surrounding rock (Φn must be more than twice of that in the reservoir (Φs; the probability of hydrocarbon reservoirs distribution decreases in cases where the hydrodynamic force is too high or too low and when the rocks have too coarse or too fine grains.

Lithological and Mineralogical Characteristics and Forming Conditions of the Jurassic Sediments on the West Siberian Basin

Directory of Open Access Journals (Sweden)

R.R. Khaziev

2017-11-01

Full Text Available In the present work, lithological and mineralogical features, granulometric composition, as well as reservoir properties of the formation YuV1-1 of the Ety-Purovsky oil field are considered. It is established that the main rock-forming minerals of the reservoir – quartz, potassium feldspar and mica, also fragments of rocks, including carbonate rocks, are also found. Sandstone is diagnosed as carbonate greywack by the examined thin sections. According to the granulometry data, the formation is characterized as fine-grained sandstone with a dominant fraction of grains of 0.1-0.25 mm (47% of the total mass. According to the petrogenetic Passega diagram it was established that the formation was formed under the conditions of the gradation suspension generated in the lower parts of the fast river streams, directly at the bottom, which agrees with the literature data. Moreover, according to design factors (So, Q3, Q1, it is established that the formation is characterized by a poor degree of sorting of the sand material, as well as low roundness of grains and deteriorated reservoir properties, measured in laboratory conditions. It follows from the analysis that the reservoir is characterized by low productivity, and its development requires the use of hydraulic fracturing at an early stage of development.

Use of bore logging for the determination of lithological characteristics of the Boom clay formation and interest for correlations in clay

International Nuclear Information System (INIS)

Neerdael, B.; Bonne, A.; Manfroy, P.; Vandenberghe, N.; Fierens, E.; Laga, P.

1981-01-01

It is first recalled that the purpose of the HADES project of the CEN/SCK at Mol (Belgium) is to study the possibility of geological disposal for radioactive wastes in the Boom clay formation at a depth between +-160 and 270 m. The different steps and aspects of the site investigation are exposed, and for each of them, the specific techniques used are reviewed. One of these steps is elaborated more in detail. It covers namely the lateral extrapolation of the lithological variations as established from a very detailed analysis of the initial cored boring. Among the usefull methods, the most practical and refined results were obtained from the resistivity logs in the reconnaissance holes. Finally, examples are shown of very detailed correlation on site scale, scale of the hydrogeological entity and regional scale (occurrence of Boom clay on the belgian territory)

Airborne EM, Lithology and in-situ Data Used for Quantizing Groundwater Salinity in Zeeland (NL)

Science.gov (United States)

Meyer, U.; Siemon, B.; van Baaren, E.; Dabekaussen, W.; Delsman, J. R.; Karaoulis, M.; Gunnink, J.; Pauw, P.; Vermaas, T.

2017-12-01

In a setting of predominantly saline surface waters in Zeeland, the Netherlands, the only available shallow fresh groundwater is present in the form of freshwater lenses floating on top of the saline groundwater. This fresh water is vital for agricultural, industrial, ecological, water conservation and drinking water functions. An essential first step for managing the usable water properly is to know the present spatial fresh-brackish-saline groundwater distribution. As traditional salinity monitoring is labor-intensive, airborne electromagnetics, which is fast and can cover large areas in short time, is an efficient alternative. A consortium of BGR, Deltares and TNO conducted FRESHEM Zeeland (FREsh Salt groundwater distribution by Helicopter ElectroMagnetic survey in the Province of Zeeland) in 2014-17. An area of more than 2000 square km was surveyed using BGR's helicopter-borne geophysical system totaling to about 9,600 line-km. The HEM data, after inversion to 2.5 Million resistivity-depth models for each of the three 1D inversion procedures applied (Marquardt single site, smooth and sharp laterally constrained inversion), served as base-line information for further interpretation. A probabilistic Monte Carlo approach combines HEM resistivities, 3D lithology model data (GeoTOP), laboratory results (formation factor and surface conductivity) and local in-situ groundwater measurements for the translation of resistivity to Chloride concentration. The resulting 3D voxel model enables stakeholders to implement spatial Chloride concentration in their groundwater models.

The dynamics of sediment size and transient erosional signals in heterogeneous lithologies

Science.gov (United States)

Lyons, N. J.; Gasparini, N. M.; Crosby, B. T.; Wehrs, K.; Willenbring, J. K.

2017-12-01

preservation of a base level change signal in low order streams. This result implies that transient erosion signals inferred using topography can be transformed or destroyed in certain lithologies, complicating efforts to infer climatic and tectonic history from topography.

Lithological and petrophysical properties and prospects of oil and gas presence of Kalinsky series in Absheron

International Nuclear Information System (INIS)

Kheirov, M.B; Dilbazi, Z.H; Askerov, F.H; Imanov, A.D.

2002-01-01

Full text:The presentation is is dedicated to summarizing the results of studying lithological and petrographic peculiarities and petrophysical properties of relatively scarcely studied rocks of lower Pliocene Kalinsky Series in Absheron, particularly its lower horizons, as well as to determining the regularities of these properties change about the area, as well as along the geological section. These generalisation cover the areas of Gala, Turkany, Gala-Dubendy, Govsany, Garachukhur, Bina, Zykh, Peschany island, Chilov, Khali, Gryazevaya sopka, Pirallakhy, and they are necessary for determining the direction of exploration and increasing the efficiency of productive horizons development. Kalinsky series is represented mostly by the alternation of siltstones, sandstones and shale and subjected to lithofacial changes along the section and about the area. In the reservoir sections studied Kalinsky series is mostly of polymetallic composition and is represented by badly sorted rocks. The sorting coefficient is within the range 2.5-4.7. Sands and sandstones occur relatively seldom. Thus, Kalinsky series, and its lower horizons in particular are scarcely studied. In some areas these horizons in particular are scarcely studied. In some areas horizons are not exposed. That is why for the purpose of oil and gas presence degree clarification it is necessary to resume exploration in Absheron oil and gas bearing region Kalinsky series, and in particular in its lower horizons

Geochronology and geochemistry of lithologies of the Tabuaço W-prospect area (Northern Portugal)

Science.gov (United States)

Cerejo, Tiago; Francisco Santos, Jose; Sousa, Joao Carlos; Castanho, Nuno; Sergio, Gabriel; Ribeiro, Sara

2016-04-01

This work is focussed on lithologies occurring at Quinta de São Pedro das Águias, which is located in the Tabuaço prospect (an area of 45 km2 where exploration for W-skarn deposits is taking place, in northern Portugal, close to the Douro valley). At Quinta de São Pedro das Águias several lithologies are recognized: "normal" phyllites, black phyllites (graphite-bearing), marbles, calcsilicate (s.s.) rocks and skarns (sometimes, scheelite-bearing), belonging to the Bateiras Formation, of the Douro Group (one of the two major subdivisions of the Neoproterozoic-Cambrian Dúrico-Beirão Supergroup); Paredes da Beira-Tabuaço granite; several aplitic and pegmatitic bodies. The studied area belongs to the Central Iberian Zone, a geotectonic unit of the Iberian Variscan Chain. Rb-Sr isotope analyses done in the scope of this work, provided a 316 ± 7 Ma whole-rock isochron (MSWD = 1.7; initial 87Sr/86Sr = 0.7146) for the granitoids, using the 87Rb decay constant recently recommended by IUPAC-IUGS (Villa et al., 2015). This date is interpreted here as the emplacement age of those rocks, during a late stage of the Variscan D3. The granite revealed a S-type nature, namely because it is a muscovite granite, it shows a peraluminous composition (average A/CNK = 1.28), and the Sr and Nd isotope fingerprints (-8.9 ≤ ɛNd(316Ma) ≤ -7.8; +0.7105 ≤ 87Sr/86Sr(316Ma) ≤ 0.7182) fit into the composition of metasedimentary crust. The analysed phyllites show the following isotopic compositions: -9.7 ≤ ɛNd(316Ma) ≤ -8.2; +0.7148 ≤ 87Sr/86Sr(316Ma) ≤ 0.7188. Therefore, the isotope signatures, at 316 Ma, of the granite and of the studied metapelites overlap, suggesting that the parental magma was generated by anatexis of Grupo do Douro metasediments. According to their petrographic, geochemical and isotopic features, aplites and pegmatites are viewed as extreme differentiates from the granite. São Pedro das Águias metapelites show biotite zone parageneses

Great earthquakes along the Western United States continental margin: implications for hazards, stratigraphy and turbidite lithology

Science.gov (United States)

Nelson, C. H.; Gutiérrez Pastor, J.; Goldfinger, C.; Escutia, C.

2012-11-01

We summarize the importance of great earthquakes (Mw ≳ 8) for hazards, stratigraphy of basin floors, and turbidite lithology along the active tectonic continental margins of the Cascadia subduction zone and the northern San Andreas Transform Fault by utilizing studies of swath bathymetry visual core descriptions, grain size analysis, X-ray radiographs and physical properties. Recurrence times of Holocene turbidites as proxies for earthquakes on the Cascadia and northern California margins are analyzed using two methods: (1) radiometric dating (14C method), and (2) relative dating, using hemipelagic sediment thickness and sedimentation rates (H method). The H method provides (1) the best estimate of minimum recurrence times, which are the most important for seismic hazards risk analysis, and (2) the most complete dataset of recurrence times, which shows a normal distribution pattern for paleoseismic turbidite frequencies. We observe that, on these tectonically active continental margins, during the sea-level highstand of Holocene time, triggering of turbidity currents is controlled dominantly by earthquakes, and paleoseismic turbidites have an average recurrence time of ~550 yr in northern Cascadia Basin and ~200 yr along northern California margin. The minimum recurrence times for great earthquakes are approximately 300 yr for the Cascadia subduction zone and 130 yr for the northern San Andreas Fault, which indicates both fault systems are in (Cascadia) or very close (San Andreas) to the early window for another great earthquake. On active tectonic margins with great earthquakes, the volumes of mass transport deposits (MTDs) are limited on basin floors along the margins. The maximum run-out distances of MTD sheets across abyssal-basin floors along active margins are an order of magnitude less (~100 km) than on passive margins (~1000 km). The great earthquakes along the Cascadia and northern California margins cause seismic strengthening of the sediment, which

Structural and lithological conditioning of the large karst systems of the Sierra de los Organos, Pinar del Rio, Cuba; Condicionantes estructurales y litologicas de los grandes sistemas karsticos de la Sierra de los Organos, Pinar del Rio, Cuba

Energy Technology Data Exchange (ETDEWEB)

Diaz Guanche, C.; Ramirez Hernandez, R.; Farfan Gonzalez, H.; Estevez Cruz, E.; Ordaz Hernandez, A.; Aldana Vilas, C.

2016-07-01

he karst, a complex phenomenon, is governed by a number of variables which dictate its genesis and evolution. Among these variables tectonic settings and lithology play the main role. In Cuba, approximately 65% of the territory is occupied by karst. The Sierra de los Organos, part of Cordillera de Guaniguanico, has some of the largest karstic systems in the country. With the aim of demonstrating the relationship between the spatial and morphological development of the underground karstic systems and the geological structure and lithology of the area, several structural and morphological measurements and field observations have been made. These measurements and observations allowing us to conclude that the karstic processes take place mainly in massive, relatively homogeneous and very thick limestone in the Sierra de los Organos. Moreover, these rocks are characterized by both low porosity and a high degree of fracturing. These karstic forms are also conditioned by the existence of various fracturing systems with general NE-SW and NW-SE orientations. Interception of these fracturing systems provides, as expected, areas with the largest volumes of karstic cavities. (Author)

Recovery and Lithologic Analysis of Sediment from Hole UT-GOM2-1-H002, Green Canyon 955, Northern Gulf of Mexico

Science.gov (United States)

Kinash, N.; Cook, A.; Sawyer, D.; Heber, R.

2017-12-01

In May 2017 the University of Texas led a drilling and pressure coring expedition in the northern Gulf of Mexico, UT-GOM2-01. The holes were located in Green Canyon Block 955, where the Gulf of Mexico Joint Industry Project Leg II identified an approximately 100m thick hydrate-filled course-grained levee unit in 2009. Two separate wells were drilled into this unit: Holes H002 and H005. In Hole H002, a cutting shoe drill bit was used to collect the pressure cores, and only 1 of the 8 cores collected was pressurized during recovery. The core recovery in Hole H002 was generally poor, about 34%, while the only pressurized core had 45% recovery. In Hole H005, a face bit was used during pressure coring where 13 cores were collected and 9 cores remained pressurized. Core recovery in Hole H005 was much higher, at about 75%. The type of bit was not the only difference between the holes, however. Drilling mud was used throughout the drilling and pressure coring of Hole H002, while only seawater was used during the first 80m of pressure cores collected in Hole H005. Herein we focus on lithologic analysis of Hole H002 with the goal of documenting and understanding core recovery in Hole H002 to compare with Hole H005. X-ray Computed Tomography (XCT) images were collected by Geotek on pressurized cores, mostly from Hole H005, and at Ohio State on unpressurized cores, mostly from Hole H002. The XCT images of unpressurized cores show minimal sedimentary structures and layering, unlike the XCT images acquired on the pressurized, hydrate-bearing cores. Only small sections of the unpressurized cores remained intact. The unpressurized cores appear to have two prominent facies: 1) silt that did not retain original sedimentary fabric and often was loose within the core barrel, and 2) dense mud sections with some sedimentary structures and layering present. On the XCT images, drilling mud appears to be concentrated on the sides of cores, but also appears in layers and fractures within

Updated procedures for using drill cores and cuttings at the Lithologic Core Storage Library, Idaho National Laboratory, Idaho

Science.gov (United States)

Hodges, Mary K.V.; Davis, Linda C.; Bartholomay, Roy C.

2018-01-30

In 1990, the U.S. Geological Survey, in cooperation with the U.S. Department of Energy Idaho Operations Office, established the Lithologic Core Storage Library at the Idaho National Laboratory (INL). The facility was established to consolidate, catalog, and permanently store nonradioactive drill cores and cuttings from subsurface investigations conducted at the INL, and to provide a location for researchers to examine, sample, and test these materials.The facility is open by appointment to researchers for examination, sampling, and testing of cores and cuttings. This report describes the facility and cores and cuttings stored at the facility. Descriptions of cores and cuttings include the corehole names, corehole locations, and depth intervals available.Most cores and cuttings stored at the facility were drilled at or near the INL, on the eastern Snake River Plain; however, two cores drilled on the western Snake River Plain are stored for comparative studies. Basalt, rhyolite, sedimentary interbeds, and surficial sediments compose most cores and cuttings, most of which are continuous from land surface to their total depth. The deepest continuously drilled core stored at the facility was drilled to 5,000 feet below land surface. This report describes procedures and researchers' responsibilities for access to the facility and for examination, sampling, and return of materials.

Great earthquakes along the Western United States continental margin: implications for hazards, stratigraphy and turbidite lithology

Directory of Open Access Journals (Sweden)

C. H. Nelson

2012-11-01

Full Text Available We summarize the importance of great earthquakes (M_w ≳ 8 for hazards, stratigraphy of basin floors, and turbidite lithology along the active tectonic continental margins of the Cascadia subduction zone and the northern San Andreas Transform Fault by utilizing studies of swath bathymetry visual core descriptions, grain size analysis, X-ray radiographs and physical properties. Recurrence times of Holocene turbidites as proxies for earthquakes on the Cascadia and northern California margins are analyzed using two methods: (1 radiometric dating (¹⁴C method, and (2 relative dating, using hemipelagic sediment thickness and sedimentation rates (H method. The H method provides (1 the best estimate of minimum recurrence times, which are the most important for seismic hazards risk analysis, and (2 the most complete dataset of recurrence times, which shows a normal distribution pattern for paleoseismic turbidite frequencies. We observe that, on these tectonically active continental margins, during the sea-level highstand of Holocene time, triggering of turbidity currents is controlled dominantly by earthquakes, and paleoseismic turbidites have an average recurrence time of ~550 yr in northern Cascadia Basin and ~200 yr along northern California margin. The minimum recurrence times for great earthquakes are approximately 300 yr for the Cascadia subduction zone and 130 yr for the northern San Andreas Fault, which indicates both fault systems are in (Cascadia or very close (San Andreas to the early window for another great earthquake.

On active tectonic margins with great earthquakes, the volumes of mass transport deposits (MTDs are limited on basin floors along the margins. The maximum run-out distances of MTD sheets across abyssal-basin floors along active margins are an order of magnitude less (~100 km than on passive margins (~1000 km. The great earthquakes along the Cascadia and northern California margins

LITHOLOGIC CONDITIONS OF THE WATER TABLE LOGGING IN THE AREA OF HAĆKI VILLAGE IN THE BIELSKA PLAIN

Directory of Open Access Journals (Sweden)

Krzysztof Micun

2016-05-01

Full Text Available The aim of the study was to examine lithological conditions of the water table in the area of Haćki village located in the Bielska Plain. The study involved the measurements of water level in dug wells, hand drill probing to a depth of 5 m, acquiring the samples of water-bearing deposits and analysing their granulation. The results of analyses allowed to calculate the permeability coefficient. The geological structure of the area is dominated by dusty deposits of various origins. Such deposits’ formation directly affects the conditions of filtration and depth of the water table. Groundwater logging near Haćki village in the Bielska Plain appears at a depth of several tens of centimeters to 2 meters in the depressions field and up a little over 5 meters in the case of higher ground surfaces. The presence of perched water was revealed on the hills, periodic leachates at the foot of the hills and scarps and one periodic spring. Water-bearing deposits are medium sands, fine sands and loamy fine sands or fine sands with silt. Consequently, the permeability coefficient is low or even very low. Its values range from 0,001 m·d-1 to 3,8 m·d-1 (d – 24 hours. The widespread presence of dusty deposits in the area affects the limited efficiency of the water table.

Porosity Development in a Coastal Setting: A Reactive Transport Model to Assess the Influence of Heterogeneity of Hydrological, Geochemical and Lithological Conditions

Science.gov (United States)

Maqueda, A.; Renard, P.; Cornaton, F. J.

2014-12-01

Coastal karst networks are formed by mineral dissolution, mainly calcite, in the freshwater-saltwater mixing zone. The problem has been approached first by studying the kinetics of calcite dissolution and then coupling ion-pairing software with flow and mass transport models. Porosity development models require high computational power. A workaround to reduce computational complexity is to assume the calcite dissolution reaction is relatively fast, thus equilibrium chemistry can be used to model it (Sanford & Konikow, 1989). Later developments allowed the full coupling of kinetics and transport in a model. However kinetics effects of calcite dissolution were found negligible under the single set of assumed hydrological and geochemical boundary conditions. A model is implemented with the coupling of FeFlow software as the flow & transport module and PHREEQC4FEFLOW (Wissmeier, 2013) ion-pairing module. The model is used to assess the influence of heterogeneities in hydrological, geochemical and lithological boundary conditions on porosity evolution. The hydrologic conditions present in the karst aquifer of Quintana Roo coast in Mexico are used as a guide for generating inputs for simulations.

Ca isotopes in the Ebro River Basin: mixing and lithological tracer

Science.gov (United States)

Guerrot, C.; Negrel, P. J.; Millot, R.; Petelet-Giraud, E.; Brenot, A.

2012-12-01

A large investigation of the Ebro River catchment was done in the past years regarding hydrogen, oxygen, lithium, boron, sulphur and oxygen from SO4 and strontium isotope measurements together with major and trace elements in the dissolved load of 25 river samples collected within the Ebro River Basin in Spain (Millot et al., Geophysical Research Abstracts, Vol. 14, EGU2012-2062, 2012). The Ebro River (928 km long, 85,530 km2 drainage basin) located in North-Eastern Spain rises near the Atlantic coast in the Cantabrian Mountains and flows into the western Mediterranean Sea through several large cities and agricultural, mining and industrial areas. The river is one of the largest contributors of freshwater in the Mediterranean Sea and ends in the Ebro delta, one of the most important wetlands in Europe. Bedrocks of the Ebro River Basin are mainly dominated by carbonates and evaporites from the Paleozoic and Mesozoic terrains. The Ebro river mainstream was sampled at Amposta one time per month between June 2005 and May 2006 and secondly, the Ebro River along its main course and its main tributaries were sampled during one field campaign in April 2006. The behaviour of Ca and its isotopes during water/rock interactions at the scale of a large river basin having various lithologies will be investigated in addition with Sr, S (SO4) and O (SO4) isotopes. One objective is to characterize the processes controlling the isotope signatures of a large river draining predominantly sedimentary bedrocks. The δ44Ca ratio (δ44/40 normalised to Seawater) ranged between -0.87 and -1.09‰ along the Ebro main stream, increasing towards the delta as the Ca content increase. In Amposta, the δ44Ca ratio ranged between -0.66 and -1.04‰ and tends to decrease with the increasing discharge. These variations are very similar to those given by the 87Sr/86Sr ratios and Sr contents. For the tributaries, the δ44Ca ratio ranged between -0.43 and -1.04‰ whereas the anhydrite-gypsum bedrock

The silicon isotopic composition of fine-grained river sediments and its relation to climate and lithology

Science.gov (United States)

Bayon, G.; Delvigne, C.; Ponzevera, E.; Borges, A. V.; Darchambeau, F.; De Deckker, P.; Lambert, T.; Monin, L.; Toucanne, S.; André, L.

2018-05-01

The δ30Si stable isotopic composition of silicon in soils and fine-grained sediments can provide insights into weathering processes on continents, with important implications on the Si budget of modern and past oceans. To further constrain the factors controlling the distribution of Si isotopes in sediments, we have analysed a large number (n = 50) of separate size-fractions of sediments and suspended particulate materials collected near the mouth of rivers worldwide. This includes some of the world's largest rivers (e.g. Amazon, Congo, Mackenzie, Mississippi, Murray-Darling, Nile, Yangtze) and rivers from the case study areas of the Congo River Basin and Northern Ireland. Silt-size fractions exhibit a mean Si isotopic composition (δ30Si = -0.21 ± 0.19‰; 2 s.d.) similar to that previously inferred for the upper continental crust. In contrast, clay-size fractions display a much larger range of δ30Si values from -0.11‰ to -2.16‰, which yield a global δ30Siclay of -0.57 ± 0.60‰ (2 s.d.) representative of the mean composition of the average weathered continental crust. Overall, these new data show that the Si isotopic signature transported by river clays is controlled by the degree of chemical weathering, as inferred from strong relationships with Al/Si ratios. At a global scale, the clay-bound Si isotopic composition of the world's largest river systems demonstrates a link with climate, defining a general correlation with mean annual temperature (MAT) in corresponding drainage basins. While the distribution of Si isotopes in river sediments also appears to be influenced by the tectonic setting, lithological effects and sediment recycling from former sedimentary cycles, our results pave the way for their use as paleo-weathering and paleo-climate proxies in the sedimentary record.

Lithological Influences on Occurrence of High-Fluoride Waters in The Central Kenya Rift

Science.gov (United States)

Olaka, L. A.; Musolff, A.; Mulch, A.; Olago, D.; Odada, E. O.

2013-12-01

rock samples were also collected and analysed for fluoride, and rock samples were subjected to petrographic investigations and X-ray diffraction. The fluoride levels in surface and groundwater for the dry season range from 0.019 - 50.14 mg/L, on average above the WHO permissible limit. The high fluoride occurs both in the lake and groundwater. Preliminary petrographic studies show considerable fluoride in micas. The study is on-going and plans to present the relative abundances of fluoride in the lithology as the sources and the fluoride enrichment pathways of the groundwater within the Central Kenya rift.

Prediction of acid mine drainage generation potential of various lithologies using static tests: Etili coal mine (NW Turkey) as a case study.

Science.gov (United States)

Yucel, Deniz Sanliyuksel; Baba, Alper

2016-08-01

The Etili neighborhood in Can County (northwestern Turkey) has large reserves of coal and has been the site of many small- to medium-scale mining operations since the 1980s. Some of these have ceased working while others continue to operate. Once activities cease, the mining facilities and fields are usually abandoned without rehabilitation. The most significant environmental problem is acid mine drainage (AMD). This study was carried out to determine the acid generation potential of various lithological units in the Etili coal mine using static test methods. Seventeen samples were selected from areas with high acidic water concentrations: from different alteration zones belonging to volcanic rocks, from sedimentary rocks, and from coals and mine wastes. Static tests (paste pH, standard acid-base accounting, and net acid generation tests) were performed on these samples. The consistency of the static test results showed that oxidation of sulfide minerals, especially pyrite-which is widely found not only in the alteration zones of volcanic rocks but also in the coals and mine wastes-is the main factor controlling the generation of AMD in this mine. Lack of carbonate minerals in the region also increases the occurrence of AMD.

Dynamics of soil organic carbon in density fractions during post-agricultural succession over two lithology types, southwest China.

Science.gov (United States)

Wen, Li; Li, Dejun; Chen, Hao; Wang, Kelin

2017-10-01

Agricultural abandonment has been proposed as an effective way to enhance soil organic carbon (SOC) sequestration. Nevertheless, SOC sequestration in the long term is largely determined by whether the stable SOC fractions will increase. Here the dynamics of SOC fractions during post-agricultural succession were investigated in a karst region, southwest China using a space-for-time substitution approach. Cropland, grassland, shrubland and secondary forest were selected from areas underlain by dolomite and limestone, respectively. Density fractionation was used to separate bulk SOC into free light fraction (FLFC) and heavy fraction (HFC). FLFC contents were similar over dolomite and limestone, but bulk SOC and HFC contents were greater over limestone than over dolomite. FLFC content in the forest was greater than in the other vegetation types, but bulk SOC and HFC contents increased from the cropland through to the forest for areas underlain by dolomite. The contents of bulk SOC and its fractions were similar among the four vegetation types over limestone. The proportion of FLFC in bulk SOC was higher over dolomite than over limestone, but the case was inverse for the proportion of HFC, indicating SOC over limestone was more stable. However, the proportions of both FLFC and HFC were similar among the four vegetation types, implying that SOC stability was not changed by cropland conversion. Exchangeable calcium explained most of the variance of HFC content. Our study suggests that lithology not only affects SOC content and its stability, but modulates the dynamics of SOC fractions during post-agricultural succession. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lithological and structural bedrock model of the Haestholmen study site, Loviisa, SE Finland

Energy Technology Data Exchange (ETDEWEB)

Front, K.; Paulamaeki, S.; Ahokas, H.; Anttila, P

1999-10-01

The Haestholmen study site is located within the anorogenic Wiborg rapakivi granite batholith, 1640 1630 Ma in age. The bedrock consists of various rapakivi granites, which can be divided into three groups or lithological units: (1) wiborgite and pyterlite, (2) porphyritic rapakivi granite, and (3) even-grained or weakly porphyritic rapakivi granite, pyterlite being the dominant rock type. The evengrained and weakly porphyritic rapakivi granite has been interpreted to form a younger intrusive unit with a thickness of ca. 500 m, dipping approx. 20 deg to the NNW-NNE. Surface fractures form a distinct orthogonal system, with three perpendicular fracture directions: fractures dipping steeply (dip >75 deg) to the NE-SW and NW-SE plus subhorizontal (dip <30 deg) fractures. The fracturing in the outcrops is sparse,the average fracture frequency being 0.6 fractures/m. The majority of the fractures in the drill cores are horizontal or very gently dipping and there is no difference in fracture orientations in regard to rock type or depth. Core samples are usually slightly fractured (1 - 3 fractures/m), even-grained rapakivi granites being in places abundantly fractured (3 10 fractures/m. The broken sections in Haestholmen core samples represent about 4.6 % of the total length of the samples. Calcite, dolomite, Fe- hydroxides and clay minerals (illite, montmorillonite and kaolinite) form the most typical fracture mineral phases throughout the drill cores. Core discing is locally seen as repeated fracture-like subparallel cracks in core with spacing of about some millimetres to tens of millimetres. The structural model contains 27 structures (denoted by the term R+number), more than half of which have been verified by direct observations from boreholes or from the VLJ repository. The remaining structures are mainly based on the geophysical interpretation, and have been classified as probable or possible fracture zones. In addition, local structures with uncertain orientation

Deep Recycling of Sedimentary Lithologies in Subduction Zones: Geochemical and Physical Constraints from Phase Equilibria and Synchrotron-Based Multi-Anvil Experiments at 15-25 GPa

Science.gov (United States)

Rapp, R. P.; Nishiyama, N.; Irifune, T.; Inoue, T.; Yamasaki, D.

2003-12-01

Ocean island basalts (OIBs) provide geochemical evidence for the presence of crustally-derived sedimentary material in the deep mantle plume source region for EM-type OIBs, and global seismic tomography provides us with dramatic images of subducted slabs, presumably carrying a sediment component, penetrating through the transition zone and into the lower mantle, in some cases to the core-mantle boundary. In an effort to better constrain the geochemical effects of deeply recycled sedimentary material in subduction zones, and their role in the petrogenesis of EM-type OIBs, we have undertaken a series of phase equlibria experiments in the multi-anvil apparatus at 10-25 GPa, using natural sediment lithologies as starting materials. The goal of these experiments is to identify the dominant phases in deeply subducted sediments, constrain their P-T stability limits, and to assess their role in crustal recycling and element redistribution in the deep mantle during subduction. The phase equilibria experiments were performed in a 2000-ton Kawai-type apparatus, using tungsten carbide cubes with 3 mm TEL and Cr-doped MgO and zirconia pressure media. A cylindrical lanthanum chromite heater was used, along with short (gold capsules to minimize thermal gradients and to retain the small amounts of water (< 1 wt%) present in the starting material, and long run-durations (12-48 hours) in order to facilitate future analyses of the dominant phases for key trace elements using the ion microprobe. Our preliminary results at 10-25 GPa indicate that K-hollandite (KalSi3O3) and stishovite are the primary high-pressure phases in the sediment composition, with subordinate garnet and an as-yet-unidentified (possibly hydrous) Al-silicate phase present as well. These results suggest that K-hollandite is the primary repository for incompatible elements (e.g., La, Ce, Sr, Ba, Rb, etc., and the heat-producing elements K, U and Th) in sedimentary material recycled into the deep mantle via

Integration of spectral, spatial and morphometric data into lithological mapping: A comparison of different Machine Learning Algorithms in the Kurdistan Region, NE Iraq

Science.gov (United States)

Othman, Arsalan A.; Gloaguen, Richard

2017-09-01

Lithological mapping in mountainous regions is often impeded by limited accessibility due to relief. This study aims to evaluate (1) the performance of different supervised classification approaches using remote sensing data and (2) the use of additional information such as geomorphology. We exemplify the methodology in the Bardi-Zard area in NE Iraq, a part of the Zagros Fold - Thrust Belt, known for its chromite deposits. We highlighted the improvement of remote sensing geological classification by integrating geomorphic features and spatial information in the classification scheme. We performed a Maximum Likelihood (ML) classification method besides two Machine Learning Algorithms (MLA): Support Vector Machine (SVM) and Random Forest (RF) to allow the joint use of geomorphic features, Band Ratio (BR), Principal Component Analysis (PCA), spatial information (spatial coordinates) and multispectral data of the Advanced Space-borne Thermal Emission and Reflection radiometer (ASTER) satellite. The RF algorithm showed reliable results and discriminated serpentinite, talus and terrace deposits, red argillites with conglomerates and limestone, limy conglomerates and limestone conglomerates, tuffites interbedded with basic lavas, limestone and Metamorphosed limestone and reddish green shales. The best overall accuracy (∼80%) was achieved by Random Forest (RF) algorithms in the majority of the sixteen tested combination datasets.

Procedures for use of, and drill cores and cuttings available for study at, the Lithologic Core Storage Library, Idaho National Engineering Laboratory, Idaho

International Nuclear Information System (INIS)

Davis, L.C.; Hannula, S.R.; Bowers, B.

1997-03-01

In 1990, the US Geological Survey, in cooperation with the US Department of Energy, Idaho Operations Office, established the Lithologic Core Storage Library at the Idaho National Engineering Laboratory (INEL). The facility was established to consolidate, catalog, and permanently store nonradioactive drill cores and cuttings from investigations of the subsurface conducted at the INEL, and to provide a location for researchers to examine, sample, and test these materials. The facility is open by appointment to researchers for examination, sampling, and testing of cores and cuttings. This report describes the facility and cores and cuttings stored at the facility. Descriptions of cores and cuttings include the well names, well locations, and depth intervals available. Most cores and cuttings stored at the facility were drilled at or near the INEL, on the eastern Snake River Plain; however, two cores drilled on the western Snake River Plain are stored for comparative studies. Basalt, rhyolite, sedimentary interbeds, and surficial sediments compose the majority of cores and cuttings, most of which are continuous from land surface to their total depth. The deepest core stored at the facility was drilled to 5,000 feet below land surface. This report describes procedures and researchers' responsibilities for access to the facility, and examination, sampling, and return of materials

Melting mode and source lithology inferred from trace element systematic in historical olivine from Lanzarote, Canary Islands

Science.gov (United States)

Gómez-Ulla, Alejandra; Sigmarsson, Olgeir; Guðfinnsson, Guðmundur H.

2017-04-01

Trace element concentrations and ratios in olivine phenocrysts, such as fractionation-corrected Ni x (FeO/MgO) and Fe/Mn, have been shown useful as probes of pyroxenite derived component in mixtures of primary mantle melts (e.g. Sobolev et al., 2007). For instance, higher Ni and lower Mn and Ca contents are expected in partial melts of pyroxenite compared to those of lherzolite. We have measured trace element concentrations in olivine from 1730-1736 AD (Timanfaya) and 1824 AD eruptions in Lanzarote (Canary Islands), which erupted mafic and mantle nodule bearing magmas, ranging in composition from highly silica-undersaturated basanite through alkali basalt to tholeiite. The early basanite exhibit the largest olivine trace element variation covering the range of those from MORB and OIB worldwide, whereas later erupted tholeiite have values typical from pyroxenite derived melts. The Fo value decreased systematically with time during the 1730-36 eruption and the proportion of silica-saturated primary melt increased in the parental magma mixture with time. At the end of the eruption, tholeiite magmas crystallized olivine with, increasing concentrations of Mn and Ca and higher Ca/Al at relatively uniform Ni x (FeO/MgO) and Fe/Mn, all of which is readily explained by increased decompression melting at lower temperature. The basanite from the eruption that took place in 1824 AD has olivine with even higher Fo value and trace element variability similar those of the Timanfaya basanite. The fact that the Lanzarote basanite contain olivine with trace element systematic spanning that of MORB and pyroxenite melt can be explained by CO2-flux melting of a lithologically heterogeneous source, generating the diverse compositions. Initial reactive porous flow through depleted oceanic lithosphere and equilibration with dunitic restite of percolating pyroxenite melt may have amplified the observed Ni depletion in olivine of the earliest basanite. The fact that olivine compositions and

Mapping of lithologic and structural units using multispectral imagery. [Afar-Triangle/Ethiopia and adjacent areas (Ethiopian Plateau, Somali Plateau, and parts of Yemen and Saudi Arabia)

Science.gov (United States)

Kronberg, P. (Principal Investigator)

1974-01-01

The author has identified the following significant results. ERTS-1 MSS imagery covering the Afar-Triangle/Ethiopia and adjacent regions (Ethiopian Plateau, Somali Plateau, and parts of Yemen and Saudi Arabi) was applied to the mapping of lithologic and structural units of the test area at a scale 1:1,000,000. Results of the geological evaluation of the ERTS-1 imagery of the Afar have proven the usefullness of this type of satellite data for regional geological mapping. Evaluation of the ERTS images also resulted in new aspects of the structural setting and tectonic development of the Afar-Triangle, where three large rift systems, the oceanic rifts of the Red Sea and Gulf of Aden and the continental East African rift system, seem to meet each other. Surface structures mapped by ERTS do not indicate that the oceanic rift of the Gulf of Aden (Sheba Ridge) continues into the area of continental crust west of the Gulf of Tadjura. ERTS data show that the Wonji fault belt of the African rift system does not enter or cut through the central Afar. The Aysha-Horst is not a Horst but an autochthonous spur of the Somali Plateau.

Tectonic and lithological controls on fluvial landscape development in central-eastern Portugal: Insights from long profile tributary stream analyses

Science.gov (United States)

Martins, António A.; Cabral, João; Cunha, Pedro P.; Stokes, Martin; Borges, José; Caldeira, Bento; Martins, A. Cardoso

2017-01-01

This study examines the long profiles of tributaries of the Tagus and Zêzere rivers in Portugal (West Iberia) in order to provide new insights into patterns, timing, and controls on drainage development during the Quaternary incision stage. The studied streams are incised into a relict culminant fluvial surface, abandoned at the beginning of the incision stage. The streams flow through a landscape with bedrock variations in lithology (mainly granites and metasediments) and faulted blocks with distinct uplift rates. The long profiles of the analyzed streams record an older transitory knickpoint/knickzone separating (1) an upstream relict graded profile, with lower steepness and higher concavity, that reflects a long period of quasi-equilibrium conditions reached after the beginning of the incision stage, and (2) a downstream rejuvenated long profile, with steeper gradient and lower concavity, particularly for the final reach, which is often convex. The rejuvenated reaches testify to the upstream propagation of several incision waves, interpreted as the response of each stream to increasing crustal uplift and prolonged periods of base-level lowering by the trunk drainages, coeval with low sea level conditions. The morphological configurations of the long profiles enabled spatial and relative temporal patterns of incisions to be quantified. The incision values of streams flowing on the Portuguese Central Range (PCR; ca. 380-150 m) are variable but generally higher than the incision values of streams flowing on the adjacent South Portugal Planation Surface (SPPS; ca. 220-110 m), corroborating differential uplift of the PCR relative to the SPPS. Owing to the fact that the relict graded profiles can be correlated with the Tagus River T1 terrace (1.1-0.9 My) present in the study area, incision rates can be estimated (1) for the streams located in the PCR, 0.38-0.15 m/ky and (2) for the streams flowing on the SPPS, 0.22-0.12 m/ky. The differential uplift inferred in the

Lithological and petrophysical properties and prospects of oil and gas presence of Kalinsky series in Absheron

International Nuclear Information System (INIS)

Kheirov, M.B; Dilbazi, Z.H; Askerov, F.H; Imanov, A.D

2002-01-01

Full text: The presentation is dedicated to summarizing the results of studying lithological and petrographic peculiarities and petrophysical properties of relatively scarcely studied rocks of lower Pliocene Kalinsky Series in Absheron, particularly its lower horizons, as well as to determining the regularities of these properties change about the area, as well as along the geological section.These generalizations cover the areas of Gala, Turkany,Gala-Dubendy,Govsany,Garachukhur, Bina, Zykh, Peschany island, Chilov, Khali, Gryazevaya sopka, Pirallakhy, and they are necessary for determining the direction of exploration and increasing the efficiently of productive horizons development.Kalinsky series (KaS) is represented mostly by the alternation of siltstones,sandstones and shale and subjected to lithofacial changes along the section and about the area.Within the area under analysis the Kalinsky series thickness is changeable and decreases towards north-west (the crest), besides it pinches out, thus promoting lithostratigraphical traps occurrence. In this direction the arenosity of reservoir rocks increases.The The exposure of the 4-th and 5-th horizons of Kalinsky series in Peschany Island, Zyrya and Gryazevaya sopka gives us an opportunity to expect the occurrence of the corresponding formations in other areas as well. In the reservoir sections studied Kalinsky series is mostly of polymictic composition and is represented by badly sorted rocks.the sorting coefficient is within the range 2,5-4,7.Sands and sandstones occur relatively seldom.Silt fraction mostly prevails in their granulometric composition.The sand fraction content is close to the content of silt fraction in Surakhany, Garachukhur, Gum adasy, Zykh and Govsany (Fig.1).The reservoir rocks clayiness ranges within 12%-35%.Pelite fraction is the smallest in Surakhany, Peschany Island and Bina, while in Turkany, Gala, Gala-dubendy, Turkany-deniz and Gryazevaya sopka this fraction increases, attaining 28

Lithologically controlled detachment strength and steady state since 10 Ma: Exploring the Alpine wedge using critical taper analysis combined with low-temperature thermochronometry

Science.gov (United States)

von Hagke, Christoph; Oncken, Onno; Ortner, Hugo; Cederbom, Charlotte

2014-05-01

Although evidence for weak detachments underlying foreland thrust belts exists, very little is known about the lateral variations in effective strength, as well as the geological nature of such variations. Using critical taper analysis, we show that a detailed and systematic measurement of surface slope of the Central European Alps reveals variations in strength along the detachment, based on the argument that the Alps are close to the critical state. We show that the basal detachment is very weak near the deformation front but strengthens towards the hinterland. These changes in detachment strength coincide with changes of detachment lithology in the hangingwall and footwall respectively, emphasizing the dominant role of weak shales. The very low strength values we find in shales in the frontal part of the alpine sole detachment are caused partly by slightly elevated pore pressures but may also require additional mechanisms of dynamic weakening. Using the constraints on the present day alpine taper, we investigate the change in taper through time. To this end, we produced new apatite fission track and apatite (U-Th)/He data from the Alpine orogenic front, the Austrian Subalpine Molasse. We combine this data set with existing thermochronometry, and reconstruct the Central Alpine pro-wedge geometry at 10 Ma. We show that the taper of the Central Alps has not changed significantly and presumably remained close to kinematic and mass flux steady state since then. This indicates a feedback between ongoing shortening and erosion at low rates during the Late Neogene to present.

The influence of upper-crust lithology on topographic development in the central Coast Ranges of California

Science.gov (United States)

Garcia, A.F.; Mahan, S.A.

2012-01-01

A fundamental geological tenet is that as landscapes evolve over graded to geologic time, geologic structures control patterns of topographic distribution in mountainous areas such that terrain underlain by competent rock will be higher than terrain underlain by incompetent rock. This paper shows that in active orogens where markedly weak and markedly strong rocks are juxtaposed along contacts that parallel regional structures, relatively high topography can form where strain is localized in the weak rock. Such a relationship is illustrated by the topography of the central Coast Ranges between the Pacific coastline and the San Andreas fault zone (SAFZ), and along the length of the Gabilan Mesa (the "Gabilan Mesa segment" of the central Coast Ranges). Within the Gabilan Mesa segment, the granitic upper crust of the Salinian terrane is in contact with the accretionary-prism m??lange upper crust of the Nacimiento terrane along the inactive Nacimiento fault zone. A prominent topographic lineament is present along most of this lithologic boundary, approximately 50 to 65. km southwest of the SAFZ, with the higher topography formed in the m??lange on the southwest side of the Nacimiento fault. This paper investigates factors influencing the pattern of topographic development in the Gabilan Mesa segment of the central Coast Ranges by correlating shortening magnitude with the upper-crust compositions of the Salinian and Nacimiento terranes. The fluvial geomorphology of two valleys in the Gabilan Mesa, which is within the Salinian terrane, and alluvial geochronology based on optically-stimulated luminescence (OSL) age estimates, reveal that the magnitude of shortening accommodated by down-to-the-southwest tilting of the mesa since 400ka is less than 1 to 2m. Our results, combined with those of previous studies, indicate that at least 63% to 78% of late-Cenozoic, northeast-southwest directed, upper-crustal shortening across the Gabilan Mesa segment has been accommodated

Pedological Heterogeneity of Soils Developed from Lithologies of the Pirambóia, Sanga-do-Cabral, and Guará Geological Formations in Southern Brazil

Directory of Open Access Journals (Sweden)

Pablo Grahl dos Santos

Full Text Available ABSTRACT The source material is one of the factors that most influence soil genesis and the mainly responsible for the nature, composition, and behavior of the soil. Given the geological complexity of the Santa Maria River basin, the objective of this study was to investigate whether the new lithologies described recently may be responsible for a greater variation in soil properties, as well as in the soil taxonomy itself. The study area is located in the municipality of Rosário do Sul, RS, Brazil at 30° 15’ 28” S and 54° 54’ 50” W, with average altitude of 132 m and climate type Cfa. This study was supported by a cartographic base composed of topographic charts, geological maps, satellite images, digital elevation models, and maps of geomorphometric variables, with the support of GPS receivers and GIS. Topolithosequences were defined from soils developed from the Pirambóia, Sanga-do-Cabral, and Guará Formations, and soil profiles were chosen based on types of source materials, variations in relief, and altitude. A classical model of slope compartmentalization was applied for correlation of the geomorphic surfaces with pedogenesis. Soil profiles were described in a general and morphological manner, and soil samples were collected for analysis. The physical and chemical properties determined were particle size, active and potential acidity, organic C content, Ca2+, Mg2+, K+, and Al3+. The sum of bases, CEC, flocculation activity and degree of flocculation of the clay fraction, and base (V, aluminum (m, and sodium saturation were calculated. Soil properties were evaluated through factor analysis and grouping, which allowed profiles to be grouped based on their variables and identification of which variables were preponderant in distinguishing them. Furthermore, multivariate analysis allowed statistical differentiation of the profiles in the same lithostratigraphic unit and in different relief positions, and also differentiation of

Defining Lithological Units by Cuttings, Core and Logging Data at Site C0009A in the Nankai Trough, Japan: IODP Expedition 319

Science.gov (United States)

Efimenko, N.; Schleicher, A. M.; Buchs, D. M.; Buret, C.; Kawabata, K.; Boutt, D. F.; Underwood, M.; Araki, E.; Byrne, T. B.; McNeill, L. C.; Saffer, D. M.; Eguchi, N. O.; Takahashi, K.; Toczko, S.; Scientists, E.

2009-12-01

The use of cuttings as an alternative or addition to core material is broadly debated in on-shore and off-shore drilling expeditions. Expedition 319 is the first IODP based Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) project using the riser-drilling method to collect cutting and core samples for scientific studies. One major scientific objective for this site was to characterise the lithology and deformation history of the Kumano forearc basin sediments and its underlying units through comparison of (i) cuttings, (ii) core, (iii) measurements while drilling, and (iv) wireline logging data. Cuttings were retrieved from each 5 m intervals from 703.9 to 1604 m, and cores were recovered from 1509.7 to 1593.9 m below sea floor. As core availability was limited, the study of cuttings was a crucial step in improving our understanding of their potential and limits for lithostratigraphical interpretations compared to core. Mineralogical and chemical analysis of cuttings and core, wireline logging data, and gamma ray data from MWD were available to define four lithostratigraphic units. These units are composed of mud and mudstone with coarser silty and sandy interbeds, and volcanic ash/tuff. Consistency between unit boundaries determined from cuttings and those determined from log data is good in terms of depth, with typical mismatches of less than 10m. Three significant problems affecting the preservation of cuttings were (1) mixing of cuttings as they travel from the drill face to the surface, (2) alteration of natural mineral and structure signatures, and (3) possible contamination from natural clay minerals with the polymer/bentonite drill mud. These difficulties can be overcome in part through the analysis of cuttings of similar sizes (1-4 mm), guided by the analyses of bulk cuttings. A more accurate quantitative characterisation of cuttings through the use of digital imaging might improve the description of lithofacies. Although the quality of cuttings is

Three-dimensional geologic mapping of the Cenozoic basin fill, Amargosa Desert basin, Nevada and California

Science.gov (United States)

Taylor, Emily M.; Sweetkind, Donald S.

2014-01-01

Understanding the subsurface geologic framework of the Cenozoic basin fill that underlies the Amargosa Desert in southern Nevada and southeastern California has been improved by using borehole data to construct three-dimensional lithologic and interpreted facies models. Lithologic data from 210 boreholes from a 20-kilometer (km) by 90-km area were reduced to a limited suite of descriptors based on geologic knowledge of the basin and distributed in three-dimensional space using interpolation methods. The resulting lithologic model of the Amargosa Desert basin portrays a complex system of interfingered coarse- to fine-grained alluvium, playa and palustrine deposits, eolian sands, and interbedded volcanic units. Lithologic units could not be represented in the model as a stacked stratigraphic sequence due to the complex interfingering of lithologic units and the absence of available time-stratigraphic markers. Instead, lithologic units were grouped into interpreted genetic classes, such as playa or alluvial fan, to create a three-dimensional model of the interpreted facies data. Three-dimensional facies models computed from these data portray the alluvial infilling of a tectonically formed basin with intermittent internal drainage and localized regional groundwater discharge. The lithologic and interpreted facies models compare favorably to resistivity, aeromagnetic, and geologic map data, lending confidence to the interpretation.

Consistent lithological units and its influence on geomechanical stratification in shale reservoir: case study from Baltic Basin, Poland.

Science.gov (United States)

Pachytel, Radomir; Jarosiński, Marek; Bobek, Kinga

2017-04-01

Geomechanical investigations in shale reservoir are crucial to understand rock behavior during hydraulic fracturing treatment and to solve borehole wall stability problem. Anisotropy should be considered as key mechanical parameter while trying to characterize shale properties in variety of scales. We are developing a concept of step-by-step approach to characterize and upscale the Consistent Lithological Units (CLU) at several scales of analysis. We decided that the most regional scale model, comparable to lithostratigraphic formations, is too general for hydraulic fracture propagation study thus a more detailed description is needed. The CLU's hierarchic model aims in upscale elastic properties with their anisotropy based on available data from vertical borehole. For the purpose of our study we have an access to continuous borehole core profile and full set of geophysical logging from several wells in the Pomeranian part of the Ordovician and Silurian shale complex belongs to the Baltic Basin. We are focused on shale properties that might be crucial for mechanical response to hydraulic fracturing: mineral components, porosity, density, elastic parameters and natural fracture pattern. To prepare the precise CLU model we compare several methods of determination and upscaling every single parameter used for consistent units secretion. Mineralogical data taken from ULTRA log, GEM log, X-ray diffraction and X-ray fluorescence were compared with Young modulus from sonic logs and Triaxial Compressive Strength Tests. The results showed the impact of clay content and porosity increase on Young's modulus reduction while carbonates (both calcite and dolomite) have stronger impact on elastic modulus growth, more than quartz, represented here mostly by detrital particles. Comparing the shales of similar composition in a few wells of different depths we concluded that differences in diagenesis and compaction due to variation in formation depth in a range of 1 km has negligible

Constraints on Weathering from Riverine Magnesium Isotope Ratios

DEFF Research Database (Denmark)

Wiechert, Uwe; Ullmann, Clemens Vinzenz; Meixner, Anette

and industrialized regions, the d26Mg values mirror the lithologies of the catchment areas: the Danubian catchment is dominated by carbonatic lithologies and in the Danube dissolved magnesium exhibits the most negative d26Mg values between -1.85 and -1.70 ‰. The mainly siliceous catchment of the river Elbe causes....... Simple mass balance calculations on the basis of the magnesium isotopes obtained for the investigated rivers imply 26 to 59 % magnesium derived from carbonatic lithologies and 41 to 74 % magnesium from siliceous lithologies. This is in contrast to estimates using conventional methods for the tribute...

Regional analysis of tertiary volcanic Calderas (western U.S.) using Landsat Thematic Mapper imagery

Science.gov (United States)

Spatz, David M.; Taranik, James V.

1989-01-01

The Landsat Thematic Mapper (TM) imagery of the Basin and Range province of southern Nevada was analyzed to identify and map volcanic rock assemblages at three Tertiary calderas. It was found that the longer-wavelength visible and the NIR TM Bands 3, 5, and 7 provide more effective lithologic discrimination than the shorter-wavelength bands, due partly to deeper penetration of the longer-wavelength bands, resulting in more lithologically driven radiances. Shorter-wavelength TM Bands 1 and 2 are affected more by surficial weathering products including desert varnish which may or may not provide an indirect link to lithologic identity. Guidelines for lithologic analysis of volcanic terrains using Landsat TM imagery are outlined.

The Bero Volganic Group: New Lithological, Stratigraphic, and Geochemical Data of this Extension of the Parana-Etendeka Igneous Province into SW Angola with Implications

Science.gov (United States)

Marsh, J.; Swart, R.

2015-12-01

The Bero Volcanic Group, an extension of the Etendeka-Paraná Igneous Province into SW Angola, forms the eroded basement to the on-shore Namibe Basin, an Early Cretaceous-Cenozoic terrestrial and marine sedimentary sequence. The igneous suite outcrops between latitudes 14.68o and 15.25o S and comprises quartz latite rheoignimbrites/lavas, tholeiitic basaltic lavas, pyroclastic/volcaniclastic deposits, minor aeolian sandstones, and mafic tholeiitic dykes and gabbroic sheets. Quartz latite lithologies dominate. In the Rio Bero area in the S quartz latites are underlain by several thin flows of basalt interbedded with, and underlain by, thin discontinuous lenses of aeolian sandstone. This sequence is consistent with the general stratigraphic sequence in the northern Etendeka of Namibia. To the N basalts and aeolian sandstones are absent and the quartz latites lie directly on Precambrian basement rocks in places. To date, data for a quartz latite correlated with a Chapecó rhyolites of the Paraná are available from only one locality in Angola. This study's wider sampling and major and trace element and radiogenic isotope analysis reveals the following: (1) all mafic rocks are high-Ti, the lavas being equivalent to the Khumiba/Urubici type; (2) mafic dykes cutting the quartz latites having affinities to the Paranapanema-Ribeira mafic lavas; (3) five quartz latite geochemical types are present, three of which are known from Etendeka/Paraná (Sarusas/Guarapuava, Khoraseb/Ourinhos and Ventura) and their stratigraphic relationships in Angola are consistent with those in the Etendeka and Paraná; (4) their Angolan occurrence significantly extends the area covered by, and potential eruptive volumes of, these silicic types; (5) two other quartz latite types are unknown in the Etendeka and Paraná and are probably products of low-volume, local eruptions. The Chinguau type is geochemically similar to the low-Ti quartz lalites of the southern Etendeka but has lower Epsilon Nd

Calcium and magnesium isotope systematics in rivers draining the Himalaya-Tibetan-Plateau region: Lithological or fractionation control?

Science.gov (United States)

Tipper, Edward T.; Galy, Albert; Bickle, Mike J.

2008-02-01

is overwhelmingly derived from carbonate weathering. The average δ44Ca value in HHCS rivers is within uncertainty of silicate rock at 0.39‰. The widespread hot springs of the High Himalaya have an average δ26Mg value of -0.46‰ and an average δ44Ca value of 0.5‰, distinct from riverine values for δ26Mg but similar to riverine δ44Ca values. Although rivers draining each major rock type have δ44Ca and δ26Mg values in part inherited from bedrock, there is no correlation with proxies for carbonate or silicate lithology such as Na/Ca ratios, suggesting that Ca and Mg are in part recycled. However, in spite of the vast contrast in vegetation density between the arid Tibetan Plateau and the tropical Lesser Himalaya, the isotopic fractionation factor for Ca and Mg between solute and rocks are not systematically different suggesting that vegetation may only recycle a small amount of Ca and Mg in these catchments. The discrepancy between solute and solid Ca and Mg isotope ratios in these rivers from diverse weathering environments highlight our lack of understanding concerning the origin and subsequent path of Ca and Mg, bound as minerals in rock, and released as cations in rivers. The fractionation of Ca and Mg isotope ratios may prove useful for tracing mechanisms of chemical alteration. Ca isotope ratios of solute riverine Ca show a greater variability than previously acknowledged. The variability of Ca isotope ratios in modern rivers will need to be better quantified and accounted for in future models of global Ca cycling, if past variations in oceanic Ca isotope ratios are to be of use in constraining the past carbon cycle.

Regional Geological Mapping in the Graham Land of Antarctic Peninsula Using LANDSAT-8 Remote Sensing Data

Science.gov (United States)

Pour, A. B.; Hashim, M.; Park, Y.

2017-10-01

Geological investigations in Antarctica confront many difficulties due to its remoteness and extreme environmental conditions. In this study, the applications of Landsat-8 data were investigated to extract geological information for lithological and alteration mineral mapping in poorly exposed lithologies in inaccessible domains such in Antarctica. The north-eastern Graham Land, Antarctic Peninsula (AP) was selected in this study to conduct a satellite-based remote sensing mapping technique. Continuum Removal (CR) spectral mapping tool and Independent Components Analysis (ICA) were applied to Landsat-8 spectral bands to map poorly exposed lithologies at regional scale. Pixels composed of distinctive absorption features of alteration mineral assemblages associated with poorly exposed lithological units were detected by applying CR mapping tool to VNIR and SWIR bands of Landsat-8.Pixels related to Si-O bond emission minima features were identified using CR mapping tool to TIR bands in poorly mapped andunmapped zones in north-eastern Graham Land at regional scale. Anomaly pixels in the ICA image maps related to spectral featuresof Al-O-H, Fe, Mg-O-H and CO3 groups and well-constrained lithological attributions from felsic to mafic rocks were detectedusing VNIR, SWIR and TIR datasets of Landsat-8. The approach used in this study performed very well for lithological andalteration mineral mapping with little available geological data or without prior information of the study region.

Application of self-organizing competition artificial neural network to logging data explanation of sandstone-hosted uranium deposits

International Nuclear Information System (INIS)

Xu Jianguo; Xu Xianli; Wang Weiguo

2008-01-01

The article describes the model construction of self-organizing competition artificial neural network, its principle and automatic recognition process of borehole lithology in detail, and then proves the efficiency of the neural network model for automatically recognizing the borehole lithology with some cases. The self-organizing competition artificial neural network has the ability of self- organization, self-adjustment and high permitting errors. Compared with the BP algorithm, it takes less calculation quantity and more rapidly converges. Furthermore, it can automatically confirm the category without the known sample information. Trial results based on contrasting the identification results of the borehole lithology with geological documentations, indicate that self-organizing artificial neural network can be well applied to automatically performing the category of borehole lithology, during the logging data explanation of sandstone-hosted uranium deposits. (authors)

Clastic compaction unit classification based on clay content and integrated compaction recovery using well and seismic data

Directory of Open Access Journals (Sweden)

Zhong Hong

2016-11-01

Full Text Available Abstract Compaction correction is a key part of paleo-geomorphic recovery methods. Yet, the influence of lithology on the porosity evolution is not usually taken into account. Present methods merely classify the lithologies as sandstone and mudstone to undertake separate porosity-depth compaction modeling. However, using just two lithologies is an oversimplification that cannot represent the compaction history. In such schemes, the precision of the compaction recovery is inadequate. To improve the precision of compaction recovery, a depth compaction model has been proposed that involves both porosity and clay content. A clastic lithological compaction unit classification method, based on clay content, has been designed to identify lithological boundaries and establish sets of compaction units. Also, on the basis of the clastic compaction unit classification, two methods of compaction recovery that integrate well and seismic data are employed to extrapolate well-based compaction information outward along seismic lines and recover the paleo-topography of the clastic strata in the region. The examples presented here show that a better understanding of paleo-geomorphology can be gained by applying the proposed compaction recovery technology.

Reprocessing of seismic shear wave and tidem data collected at the A ampersand M areas of the Savannah River Plant. Final report, September 1992--December 1995

International Nuclear Information System (INIS)

1996-05-01

The upper aquifers in the A ampersand M area of the Savannah River Site are known to be contaminated by chlorinated solvents. Remediation plans depend critically on continuity of a confining zone known as the Crouch Branch Confining Unit (C8CU), which occurs at depths between about 250 feet and 300 feet. Under DOE Contract No: DE-AC21-92MC29, administered by Morgantown Energy Technology Center (METC) surface and borehole geophysical methods were tested and further developed between 1993 and 1995 to map the lithology (clay content) and stratigraphy of the CBCU. It was found that time domain electromagnetics (TDEM) soundings were effective in mapping lithology and changes in lithology, and shear (S-) wave reflection surveys were effective in mapping stratigraphy. An integrated interpretation of the two methods yielded a rather complete image of lithology and stratigraphy of the CBCU

Hf isotope evidence for variable slab input and crustal addition in basalts and andesites of the Taupo Volcanic Zone, New Zealand

DEFF Research Database (Denmark)

Waight, Tod Earle; Troll, Valentin R.; Gamble, J.A.

2017-01-01

-Nd isotopes. Here we present new Hf isotope data for a selection of volcanic rocks and crustal lithologies fromthe Taupo Volcanic Zone (TVZ), NewZealand and propose that the scatter in Hf-Nd isotopes indicates heterogeneity in the parental magmas prior to interactions with crustal lithologies. The observed......, whereas younger lavas have probably interacted more with mid- to shallow crustal meta-sedimentary greywacke-argillite lithologies of the Permian to Cretaceous composite Torlesse Terrane. Hf-Nd isotopic compositions of meta-igneous granulite xenoliths from Mt. Ruapehu are consistent with previous...

New lithology compensated capture gamma ray system

International Nuclear Information System (INIS)

Peatross, R.F.

1976-01-01

The results of the HYDROCARBON* log after a series of field tests in which gamma rays resulting from thermal neutron capture were measured utilizing an energy analyzer and a scintillation counter of unique construction are reported. A brief discussion covers the nuclear physics required for an understanding of gamma spectral logging. Included in the explanation will be the effects of different atoms on neutrons and photons. The HYDROCARBON log utilizes these nuclear principles to record cased hole measurements and quantitatively distinguish possible productive zones from non-productive zones. Different field examples are illustrated showing the response to shaly sands, porosity and water salinity. Interpretation techniques are discussed both qualitatively and quantitatively. The HYDROCARBON log has proven to be a reliable device in the determination of water saturation in sands behind casing even when shale content and porosity are not well known. This technique is also valuable in the location of the present position of gas--oil contacts and water levels

Lithological suitability for HLW repository in Korea

International Nuclear Information System (INIS)

Kim, C.S.; Bae, D.S.; Kim, K.S.; Koh, Y.K.

2001-01-01

Regional geologic conditions of Korea were summarized with emphasis on rock mass and fracture system as a part of the research program for high level radioactive wastes disposal. The eastern margin of the Korea-China platform has been regarded as stable crotonic nature. The Mesozoic tectonic activities followed by igneous intrusion were the most vigorous crustal movement in the entire Korean peninsula. During the Jurassic-Cretaceous orogeny (180-130 Ma Bp), igneous activity resulted in forming a large batholith of Dab granitic rock (Jurassic granite). Rejuvenized igneous activities during the Cretaceous period formed the Bulguksa granite which are associated with felsic volcanic rocks and NE-SW/NNE-SSW geologic structures. The primary host rock is considered to be Daebo granite batholiths intruded in the geologic age of late Triassic to early Jurassic (205±15 Ma). The emplacement depths are in the range of 10-20 km and the crystallization occurs under the geopressure of 3∼7 kb. (author)

Compiling a national resistivity atlas of Denmark based on airborne and ground-based transient electromagnetic data

DEFF Research Database (Denmark)

Barfod, Adrian; Møller, Ingelise; Christiansen, Anders Vest

2016-01-01

in the large-scale resistivity-lithology relations, reflecting geological details such as available source material for tills. The resistivity maps also reveal a clear ambiguity in the resistivity values for different lithologies. The Resistivity Atlas is highly useful when geophysical data are to be used...

IDENTIFYING ANTHROPOGENIC METALLIC POLLUTANTS USING FREQUENCY DEPENDENT MAGNETIC SUSCEPTIBILITY MEASUREMENTS IN ABUJA METROPOLIS

Directory of Open Access Journals (Sweden)

Jatto S. Solomon

2017-07-01

Full Text Available Soil formed from lithological and weathering processes of parent rocks generally exhibit paramagnetic properties due to some minerals contained in the rocks and thus have significant value of magnetic susceptibility. This susceptibility arising from the influence of the parent rocks tend to mask anthropogenic grains pollutants released into the environment by human activities. Hence, it becomes difficult to identify the effect of the lithological and anthropogenic magnetic susceptibility in complex soil found in urban areas. The superparamagnetic effect of lithological soil, a single state domain and multi-domain state of anthropogenic grains can easily be investigated by frequency dependent measurements where readings between 0-2.0% indicates the absence of lithological influence, 2.0-8.0% indicates multi-domain grains or mixture of both single stage and multi-domian grains and 8.0-12% indicates the superparamagntic (SP grain from lithological origin. In this work frequency dependent measurements were carried out along 5 selected road networks within the 5 districts of Abuja phase 1. Measurements were also carried out in 379 random points at the surface and depth of 40.0cm to investigate the distribution of anthropogenic grains in Abuja metropolis using the Bartington susceptibility meter. Frequency dependent measurements along the selected road networks indicate0-3.0% immediately after the roads pavement to a distance of about 3.0m from the road, indicating that the magnetic susceptibility arise mostly form anthropogenic influence rather than lithological processes. At the distance of 3.0-8.0m, frequency dependent values of about 3.0-8.0% were recorded, indicating mixture of both superparamagnetic and multi-domain grains. Beyond the distance of 8.0m, the frequency dependent values are mostly above 8.0.0%, indicating virtually all SP grains. The spatial distribution frequency dependent surface map shows the presence of anthropogenic grains in

subsurface sequence delineation and saline water mapping of lagos

African Journals Online (AJOL)

A subsurface sequence delineation and saline water mapping of Lagos State was carried out. Ten (10) deep boreholes with average depth of 300 m were drilled within the sedimentary basin. The boreholes were lithologically and geophysically logged. The driller's lithological logs aided by gamma and resistivity logs, ...

Two dimentional modeling of subsurface structure over upper Benue ...

African Journals Online (AJOL)

The subsurface lithology obtained from 2D modelling of the residual field showed the presence of two lithological units. The sedimentary rock unit underlined by the basement rock consists of shales, sandstones, limestones, siltstones, clay and non-marine facies. The Basement rock units were composed of pegmatite, ...

⁵³Mn-⁵³Cr and ²⁶Al-²⁶Mg ages of a feldspathic lithology in polymict ureilites

Energy Technology Data Exchange (ETDEWEB)

Goodrich, Cyrena Anne [Planetary Science Institute. Tucson, AZ (United States); Hutcheon, Ian D. [Glenn T. Seaborg Institute. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kita, Noriko T. [Dept. of Geoscience. Univ. of Wisconsin, Madison, WI (United States); Huss, Gary R. [NASA Marshall Space Flight Center (MSFC), Huntsville, AL (United States); Cohen, Barbara Anne [Hawaii Institute of Geophysics and Planetology. Univ. of Hawaii, Honolulu, HI (United States); Keil, Klaus

2010-07-01

We report ⁵³Mn–⁵³Cr and ²⁶Al–²⁶Mg isotopic data, obtained by in-situ SIMS analysis, for feldspathic clasts in polymict ureilites DaG 319 and DaG 165. The analyzed clasts belong to the “albitic lithology,” the most abundant population of indigenous feldspathic materials in polymict ureilites, and are highly fractionated igneous assemblages of albitic plagioclase, Fe-rich pyroxenes, phosphates, ilmenite, silica, and Fe(Mn, K, P, Ti)-enriched glass. Glass in DaG 165 clast 19 has extremely high and variable ⁵⁵Mn/⁵²Cr ratios (500–58,000) and shows correlated ⁵³Cr excesses up to ~ 1500‰, clearly indicating the presence of live ⁵³Mn at the time of formation. The slope of the well-correlated isochron defined by glass and pyroxenes from this clast corresponds to (⁵³Mn/⁵⁵Mn) = (2.84 ± 0.10) × 10^-6 (2σ). Data for less ⁵⁵Mn/⁵²Cr-enriched glasses from DaG 319 clast B1, as well as phosphates from several other clasts, are consistent with this isochron. The ⁵³Mn/⁵⁵Mn ratio obtained from the isochron implies that these clasts are 0.70 ± 0.18 Ma younger than the D'Orbigny angrite, corresponding to the absolute age of 4563.72 ± 0.22 Ma. Plagioclase in DaG 319 clast B1 has a fairly constant ²⁷Al/²⁴Mg ratio of ~ 900 and shows resolvable ²⁶Mg excesses of ~ 2‰. The slope of the isochron defined by pyroxene and plagioclase in this clast is (3.0 ± 1.1) × 10^-7 (2σ), corresponding to a time difference of 5.4 (-0.3/+0.5) Ma after CAI (assuming the canonical initial ²⁶Al/²⁷Al ratio of 5 × 10^-5) and an age 0.5 (-0.3/+0.5) Ma younger than D'Orbigny. Its absolute age (relative to D'Orbigny) is 4563.9 (+ 0.4/-0.5) Ma, in agreement with the ⁵³Mn–⁵³Cr age from clast 19. These data provide the first

First field test of NAPL detection with high resolution borehole seismic imaging

International Nuclear Information System (INIS)

Geller, Jil T.; Peterson, John E.; Williams, Kenneth H.; Ajo-Franklin, Jonathan B.; Majer, Ernest L.

2002-01-01

The purpose of this field test is to evaluate the detectability of NAPLs by high resolution tomographic borehole seismic imaging. The site is a former Department of Energy (DOE) manufacturing facility in Pinellas County, Florida. Cross-hole seismic and radar measurements were made in a shallow aquifer contaminated with non-aqueous phase liquids (NAPLs). Cone penetration test (CPT) and induction logging were performed for lithology and conductivity, respectively. The main challenge is to distinguish fluid phase heterogeneities from anomalies arising from geologic structure. Our approach is to compare measurements between locations of known contamination with a nearby uncontaminated location of similar lithology where differences in signal transmission may be attributed to fluid phase changes. The CPT data show similar lithologic structure at the locations both within and outside the NAPL-contaminated area. Zones of low seismic amplitude at about 7 m depth appear more extensive in the NAPL-contaminated area. These zones may be the result of fluid phase heterogeneities (NAPL or gas), or they may be due to the lithology, i.e. attenuating nature of the layer itself, or the transition between two distinct layers. The presence of lithologic contrasts, specifically from higher permeability sands to lower permeability silts and clays, also indicate potential locations of NAPL, as they could be flow barriers to downward NAPL migration

Basalt identification by interpreting nuclear and electrical well logging measurements using fuzzy technique (case study from southern Syria)

International Nuclear Information System (INIS)

Asfahani, J.; Abdul Ghani, B.; Ahmad, Z.

2015-01-01

Fuzzy analysis technique is proposed in this research for interpreting the combination of nuclear and electrical well logging data, which include natural gamma ray, density and neutron-porosity, while the electrical well logging include long and short normal. The main objective of this work is to describe, characterize and establish the lithology of the large extended basaltic areas in southern Syria. Kodana well logging measurements have been used and interpreted for testing and applying the proposed technique. The established lithological cross section shows the distribution and the identification of four kinds of basalt, which are hard massive basalt, hard basalt, pyroclastic basalt and the alteration basalt products, clay. The fuzzy analysis technique is successfully applied on the Kodana well logging data, and can be therefore utilized as a powerful tool for interpreting huge well logging data with higher number of variables required for lithological estimations. - Highlights: • Apply fuzzy analysis technique on the nuclear and electrical well logging data of Kodana well in Southern Syria. • Determine and differentiate between four kinds of basalt. • Establish the lithological section of the studied well.

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Thermal conductivity (Ki) and thermal diffusivity (k'i) of faulted blocks govern Ti but they do not bear simple relation. Ti is significant only near the fault plane. If the lithology is dry and faulting brings adjacent hangingwall and footwall blocks of the same lithology in contact, those blocks undergo the same rate of increase in ...

Geochemical variability of the Yucatan basement: Constraints from crystalline clasts in Chicxulub impactites

Science.gov (United States)

Kettrup, B.; Deutsch, A.

2003-07-01

The 65 Ma old Chicxulub impact structure with a diameter of about 180 km is again in the focus of the geosciences because of the recently commenced drilling of the scientific well Yaxcopoil- 1. Chicxulub is buried beneath thick post-impact sediments, yet samples of basement lithologies in the drill cores provide a unique insight into age and composition of the crust beneath Yucatan. This study presents major element, Sr, and Nd isotope data for Chicxulub impact melt lithologies and clasts of basement lithologies in impact breccias from the PEMEX drill cores C-1 and Y-6, as well as data for ejecta material from the K/T boundaries at La Lajilla, Mexico, and Furlo, Italy. The impact melt lithologies have an andesitic composition with significantly varying contents of Al, Ca, and alkali elements. Their present day 87Sr/86Sr ratios cluster at about 0.7085, and 143Nd/144Nd ratios range from 0.5123 to 0.5125. Compared to the melt lithologies that stayed inside the crater, data for ejecta material show larger variations. The 87Sr/86Sr ratios range from 0.7081 for chloritized spherules from La Lajilla to 0.7151 for sanidine spherules from Furlo. The 143Nd/144Nd ratio is 0.5126 for La Lajilla and 0.5120 for the Furlo spherules. In an tCHUR(Nd)-tUR(Sr) diagram, the melt lithologies plot in a field delimited by Cretaceous platform sediments, various felsic lithic clasts and a newly found mafic fragment from a suevite. Granite, gneiss, and amphibolite have been identified among the fragments from crystalline basement gneiss. Their 87Sr/86Sr ratios range from 0.7084 to 0.7141, and their 143Nd/144Nd ratios range from 0.5121 to 0.5126. The TNdDM model ages vary from 0.7 to 1.4 Ga, pointing to different source terranes for these rocks. This leads us to believe that the geological evolution and the lithological composition of the Yucatàn basement is probably more complex than generally assumed, and Gondwanan as well as Laurentian crust may be present in the Yucatàn basement.

Model structural uncertainty quantification and hydrogeophysical data integration using airborne electromagnetic data (Invited)

DEFF Research Database (Denmark)

Minsley, Burke; Christensen, Nikolaj Kruse; Christensen, Steen

of airborne electromagnetic (AEM) data to estimate large-scale model structural geometry, i.e. the spatial distribution of different lithological units based on assumed or estimated resistivity-lithology relationships, and the uncertainty in those structures given imperfect measurements. Geophysically derived...... estimates of model structural uncertainty are then combined with hydrologic observations to assess the impact of model structural error on hydrologic calibration and prediction errors. Using a synthetic numerical model, we describe a sequential hydrogeophysical approach that: (1) uses Bayesian Markov chain...... Monte Carlo (McMC) methods to produce a robust estimate of uncertainty in electrical resistivity parameter values, (2) combines geophysical parameter uncertainty estimates with borehole observations of lithology to produce probabilistic estimates of model structural uncertainty over the entire AEM...

Informing groundwater model hydrostratigraphy with airborne time-domain electromagnetic data and borehole logs

DEFF Research Database (Denmark)

Marker, Pernille Aabye; Bauer-Gottwein, Peter; Mosegaard, Klaus

lithological information directly into groundwater models is proposed. The approach builds on a clay-fraction inversion which is a spatially variable translation of resistivity values from EM data into clay-fraction values using borehole lithological information. Hydrostratigraphical units are obtained through...... a k-means cluster analysis of the principal components of resistivity and clay-fraction values. Under the assumption that the units have uniform hydrological properties, the units constitute the hydrostratigraphy for a groundwater model. Only aquifer structures are obtained from geophysical...... and lithological data, while the estimation of the hydrological properties of the units is inversely derived from the groundwater model and hydrological data. A synthetic analysis was performed to investigate the principles underlying the clustering approach using three petrophysical relationships between...

The use of gamma spectrometry in mapping alteration zones in Olkiluoto

International Nuclear Information System (INIS)

Ojala, J.V.; Turunen, P.; Eilu, P.; Julkunen, A.; Gehoer, S.

2007-08-01

In the Olkiluoto site, a detailed gammaspectrometry log from the drill hole OL-KR27 was used to estimate the concentrations of K, Th and U. The gamma spectrometry results, lithological variations, and kaolinite and illite alteration visually mapped from the drill hole were compared. The result indicate that the Th/K ratio correlates best with lithology and that, in most cases, the changes in the ratio indicate lithological contacts and rising or falling trends of Th/K ratio with some peaks have some correlation with the kaolinite-illite alteration. From the result it is suggested that that very variable Th/K ratio is a reasonably good indicator of alteration zones even in the migmatic gneiss area in the Olkiluoto site. (orig.)

Modelling discontinuous well log signal to identify lithological ...

Indian Academy of Sciences (India)

1Indian School of Mines (ISM), Dhanbad 826 004, India. ... new wavelet transform-based algorithm to model the abrupt discontinuous changes from well log data by taking care of ...... the 11th ACM International Conference on Multimedia,.

Geomorphic and lithologic characteristics of Wadi Feiran basin ...

Indian Academy of Sciences (India)

Ayman A Ahmed

2017-08-31

Aug 31, 2017 ... (2017) 126:85 c Indian Academy of Sciences ... are different datasets and approaches to obtain information of .... the questions: is Wadi Feiran shaped by the tec- ... J. Earth Syst. Sci. (2017) 126:85. Page 5 of 25 85. Figure 3.

Lithologic boundaries from gravity and magnetic anomalies over ...

Indian Academy of Sciences (India)

Pramod Kumar Yadav

2018-03-02

Mar 2, 2018 ... nature of causative source using Euler depth solutions and radially averaged power spectrum (RAPS). Residual anomaly maps of gravity and ... the lateral boundaries and nature of the source. It seems that the source is of ..... Goldfarb R J and Richards J P,. The Economic Geology Publishing Company, pp.

Lithologic boundaries from gravity and magnetic anomalies over ...

Indian Academy of Sciences (India)

Dalma volcanics (DVs) has intruded the older Singhbhum Group of Metapelites. Despite DVs being rich in mineralisation, its boundaries are not clearly demarcated. Gravity and magnetic surveys have been attempted for mapping the boundaries in DVs. These surveys were made in the northern fringeof the DVs over an ...

Lithological responses to sea erosion along selected coastlines ...

African Journals Online (AJOL)

Mabel Anim

This makes it vulnerable to all forms of natural hazards such as landslides, ... The SCAPE model of cliff retreat and cliff-top recession which has been linked to a new flexible GIS ..... ISPRS Journal of Photogrammetry & Remote Sensing,.

Geologic Reconnaissance and Lithologic Identification by Remote Sensing

Science.gov (United States)

remote sensing in geologic reconnaissance for purposes of tunnel site selection was studied further and a test case was undertaken to evaluate this geological application. Airborne multispectral scanning (MSS) data were obtained in May, 1972, over a region between Spearfish and Rapid City, South Dakota. With major effort directed toward the analysis of these data, the following geologic features were discriminated: (1) exposed rock areas, (2) five separate rock groups, (3) large-scale structures. This discrimination was accomplished by ratioing multispectral channels.

A continental scale model for dissolved silica mobilization in North America

Science.gov (United States)

Jansen, N.; Lauerwald, R.; Hartmann, J.; Dürr, H. H.; Loos, S.; Kempe, S.; Middelkoop, H.

2009-04-01

Silicon is one of the few elements that link to both the organic and inorganic carbon cycles. Dissolved silicon (DSi) is an important nutrient in terrestrial and aquatic ecosystems. Cations accompanying the release of DSi by chemical silicate rock weathering are generally balanced by soil/atmospheric CO2. Chemical weathering is the major source of "new" bioavailable DSi for continental aquatic systems to compensate for the loss of DSi by outflow or organic precipitation and burial. We use river water chemistry data from 164 monitoring stations from the conterminous United States (WQN and NAWQA networks). Selected stations are characterized by low population density and low influence of water bodies to minimize human and DSi retention impact. Observed DSi yield in these catchments is assumed to represent natural DSi mobilization by chemical weathering. The catchments have an average size of 4400 km2 (Median: 991 km2) with a discharge weighted average DSi yield of 4.34 t SiO2 km-2a-1. To predict mobilization of DSi from chemical weathering a lumped non-linear empirical model is developed, considering control factors such as climate, morphology, hydrology, land cover, soil and lithology. A multi-lithological model approach is chosen because only very few mono-lithological catchments were identified in the dataset. The model is then extrapolated to the conterminous United States to regionally quantify the amount of DSi that is released into the river systems by chemical weathering. Small outcrops of certain lithological classes characterized by a high DSi yield are not represented on previously available small scale lithological maps. Because such localities may have a major influence on DSi fluxes from small catchments (Hartmann et al., 2009) a new high resolution lithological vector-map for North America is developed and applied in the introduced model. In accordance with previous studies, runoff and lithology are identified as the major predictors for specific DSi

The groundwater regime of the Harwell region

International Nuclear Information System (INIS)

Alexander, J.

1983-12-01

A regional hydrogeological assessment has been undertaken in the Harwell area utilizing currently available geological information and water level data. Since the dissolution and transport of any disposed waste would be controlled by the rate and direction of groundwater movement through a potential repository, a detailed knowledge of regional and local hydrogeology is essential. This study is based on the tenet that very slow groundwater movement, through a sequence of clay lithologies, is measurable at widely separated points within intervening high permeability systems. The analysis of available data from high permeability units within a regional groundwater flow-system provides a general flow model which takes into account inter-lithology water movement in general and vertical water movement across low permeability formations in particular. Groundwater contour maps have been constructed for the Chalk, Upper Greensand, Corallian and Great Oolite lithologies. These show that in the Cretaceous and Jurassic formations of the Harwell area, groundwater movement is predominantly in the horizontal direction with a smaller proportion of vertical flow taking place between adjacent formations. The potential for vertical movement, both upwards and downwards through intervening low permeability clay lithologies is evident. The results are discussed. (author)

Improved CEEMDAN-wavelet transform de-noising method and its application in well logging noise reduction

Science.gov (United States)

Zhang, Jingxia; Guo, Yinghai; Shen, Yulin; Zhao, Difei; Li, Mi

2018-06-01

The use of geophysical logging data to identify lithology is an important groundwork in logging interpretation. Inevitably, noise is mixed in during data collection due to the equipment and other external factors and this will affect the further lithological identification and other logging interpretation. Therefore, to get a more accurate lithological identification it is necessary to adopt de-noising methods. In this study, a new de-noising method, namely improved complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN)-wavelet transform, is proposed, which integrates the superiorities of improved CEEMDAN and wavelet transform. Improved CEEMDAN, an effective self-adaptive multi-scale analysis method, is used to decompose non-stationary signals as the logging data to obtain the intrinsic mode function (IMF) of N different scales and one residual. Moreover, one self-adaptive scale selection method is used to determine the reconstruction scale k. Simultaneously, given the possible frequency aliasing problem between adjacent IMFs, a wavelet transform threshold de-noising method is used to reduce the noise of the (k-1)th IMF. Subsequently, the de-noised logging data are reconstructed by the de-noised (k-1)th IMF and the remaining low-frequency IMFs and the residual. Finally, empirical mode decomposition, improved CEEMDAN, wavelet transform and the proposed method are applied for analysis of the simulation and the actual data. Results show diverse performance of these de-noising methods with regard to accuracy for lithological identification. Compared with the other methods, the proposed method has the best self-adaptability and accuracy in lithological identification.

Paleomagnetic and oxygen isotopic evidence for long term diagenesis in radiolarian chert, Pindos Mountains, Greece

Science.gov (United States)

Baltuck, Miriam

1987-02-01

Paleomagnetics was used in an attempt to improve chronostratigraphy in the Middle and Upper Jurassic radiolarian chert and siliceous mudstone of the Pindos Zone, Greece. Remanent magnetism studies showed strong magnetic intensity but scattered orientation. Orientation of some pressure solution features in the radiolarities indicates their formation under horizontal pressure, a condition which in Pindos geologic history would only have occurred during early Cretaceous or Cenozoic tectonics, indicating very late diagenesis in these parts of the section. From time of deposition to later time at which diagenesis can be documented, the Earth's magnetic field would have reversed many times. Remagnetization during solution-precipitation steps of silica diagenesis could complicate the rock magnetics. Oxygen isotopic and major element analyses of radiolarite lithologies show a systematic variation of rate of silica diagenesis in different host lithologies, thus solution-precipitation would occur at widely differing times throughout the section lithologies. If the dissolution of the silica cement were physically to free magnetic material from an earlier orientation, the result could be a partial shift toward alignment with the ambient magnetic field. Alternatively, complete reorientation of particles could have occurred at varying times in different parts of the section as a function of host lithology. During the northward movement and clockwise rotation of the Apulian subplate (including Pindos) these different lithologies could completely reorient during different stages of silica diagenesis, locking the orientation of iron magnetic moments into alignment with the ambient magnetic field at time of precipitation to result in a strong intensity but scattered orientation of Pindos rock magnetics.

Facies Analysis of Tertiary Basin-Filling Rocks of the Death Valley Regional Ground-Water System and Surrounding Areas, Nevada and California; TOPICAL

International Nuclear Information System (INIS)

Sweetkind, D.S.; Fridrich, C.J.; Taylor, Emily

2002-01-01

Existing hydrologic models of the Death Valley region typically have defined the Cenozoic basins as those areas that are covered by recent surficial deposits, and have treated the basin-fill deposits that are concealed under alluvium as a single unit with uniform hydrologic properties throughout the region, and with depth. Although this latter generalization was known to be flawed, it evidently was made because available geologic syntheses did not provide the basis for a more detailed characterization. As an initial attempt to address this problem, this report presents a compilation and synthesis of existing and new surface and subsurface data on the lithologic variations between and within the Cenozoic basin fills of this region. The most permeable lithologies in the Cenozoic basin fills are freshwater limestones, unaltered densely welded tuffs, and little-consolidated coarse alluvium. The least permeable lithologies are playa claystones, altered nonwelded tuffs, and tuffaceous and cl ay-matrix sediments of several types. In all but the youngest of the basin fills, permeability probably decreases strongly with depth owing to a typically increasing abundance of volcanic ash or clay in the matrices of the clastic sediments with increasing age (and therefore with increasing depth in general), and to increasing consolidation and alteration (both hydrothermal and diagenetic) with increasing depth and age. This report concludes with a categorization of the Cenozoic basins of the Death Valley region according to the predominant lithologies in the different basin fills and presents qualitative constraints on the hydrologic properties of these major lithologic categories

Interpretation of Flow Logs from Nevada Test Site Boreholes to Estimate Hydraulic Conductivity Using Numerical Simulations Constrained by Single-Well Aquifer Tests

Science.gov (United States)

Garcia, C. Amanda; Halford, Keith J.; Laczniak, Randell J.

2010-01-01

Hydraulic conductivities of volcanic and carbonate lithologic units at the Nevada Test Site were estimated from flow logs and aquifer-test data. Borehole flow and drawdown were integrated and interpreted using a radial, axisymmetric flow model, AnalyzeHOLE. This integrated approach is used because complex well completions and heterogeneous aquifers and confining units produce vertical flow in the annular space and aquifers adjacent to the wellbore. AnalyzeHOLE simulates vertical flow, in addition to horizontal flow, which accounts for converging flow toward screen ends and diverging flow toward transmissive intervals. Simulated aquifers and confining units uniformly are subdivided by depth into intervals in which the hydraulic conductivity is estimated with the Parameter ESTimation (PEST) software. Between 50 and 150 hydraulic-conductivity parameters were estimated by minimizing weighted differences between simulated and measured flow and drawdown. Transmissivity estimates from single-well or multiple-well aquifer tests were used to constrain estimates of hydraulic conductivity. The distribution of hydraulic conductivity within each lithology had a minimum variance because estimates were constrained with Tikhonov regularization. AnalyzeHOLE simulated hydraulic-conductivity estimates for lithologic units across screened and cased intervals are as much as 100 times less than those estimated using proportional flow-log analyses applied across screened intervals only. Smaller estimates of hydraulic conductivity for individual lithologic units are simulated because sections of the unit behind cased intervals of the wellbore are not assumed to be impermeable, and therefore, can contribute flow to the wellbore. Simulated hydraulic-conductivity estimates vary by more than three orders of magnitude across a lithologic unit, indicating a high degree of heterogeneity in volcanic and carbonate-rock units. The higher water transmitting potential of carbonate-rock units relative

Interpretation of Flow Logs from Nevada Test Site Boreholes to Estimate Hydraulic conductivity Using Numerical Simulations Constrained by Single-Well Aquifer Tests

Energy Technology Data Exchange (ETDEWEB)

Garcia, C. Amanda; Halford, Keith J.; Laczniak, Randell J.

2010-02-12

Hydraulic conductivities of volcanic and carbonate lithologic units at the Nevada Test Site were estimated from flow logs and aquifer-test data. Borehole flow and drawdown were integrated and interpreted using a radial, axisymmetric flow model, AnalyzeHOLE. This integrated approach is used because complex well completions and heterogeneous aquifers and confining units produce vertical flow in the annular space and aquifers adjacent to the wellbore. AnalyzeHOLE simulates vertical flow, in addition to horizontal flow, which accounts for converging flow toward screen ends and diverging flow toward transmissive intervals. Simulated aquifers and confining units uniformly are subdivided by depth into intervals in which the hydraulic conductivity is estimated with the Parameter ESTimation (PEST) software. Between 50 and 150 hydraulic-conductivity parameters were estimated by minimizing weighted differences between simulated and measured flow and drawdown. Transmissivity estimates from single-well or multiple-well aquifer tests were used to constrain estimates of hydraulic conductivity. The distribution of hydraulic conductivity within each lithology had a minimum variance because estimates were constrained with Tikhonov regularization. AnalyzeHOLE simulated hydraulic-conductivity estimates for lithologic units across screened and cased intervals are as much as 100 times less than those estimated using proportional flow-log analyses applied across screened intervals only. Smaller estimates of hydraulic conductivity for individual lithologic units are simulated because sections of the unit behind cased intervals of the wellbore are not assumed to be impermeable, and therefore, can contribute flow to the wellbore. Simulated hydraulic-conductivity estimates vary by more than three orders of magnitude across a lithologic unit, indicating a high degree of heterogeneity in volcanic and carbonate-rock units. The higher water transmitting potential of carbonate-rock units relative

Characterizing Geological Facies using Seismic Waveform Classification in Sarawak Basin

Science.gov (United States)

Zahraa, Afiqah; Zailani, Ahmad; Prasad Ghosh, Deva

2017-10-01

Numerous effort have been made to build relationship between geology and geophysics using different techniques throughout the years. The integration of these two most important data in oil and gas industry can be used to reduce uncertainty in exploration and production especially for reservoir productivity enhancement and stratigraphic identification. This paper is focusing on seismic waveform classification to different classes using neural network and to link them according to the geological facies which are established using the knowledge on lithology and log motif of well data. Seismic inversion is used as the input for the neural network to act as the direct lithology indicator reducing dependency on well calibration. The interpretation of seismic facies classification map provides a better understanding towards the lithology distribution, depositional environment and help to identify significant reservoir rock

INVESTIGATION OF GROUND PENETRATING RADAR FOR DETECTION OF ROAD SUBSIDENCE NORTHCOAST OF JAKARTA, INDONESIA

Directory of Open Access Journals (Sweden)

Kris Budiono

2017-07-01

Full Text Available A survey of Ground Penetrating Radar (GPR was conducted in the coastal zone of northern part of Jakarta, Indonesia. The purpose of this survey was to provide the subsurface of coastal Quaternary sedimentary features and stratigraphy disturbances associated with induce post road subsidence 2009. The possibility of subsurface lithology disturbance shown by the GPR record. This record resulted from GPR methods using SIR system 20 GSSI, 270 MHz and 400 MHz and MLF 3200 transducer. The method is a promising tool for resolving changes of physical properties in subsurface lithology condition at the natural scale due to composition changes of physical properties.The reflection data resulted that GPR can distinguish between image the basic geometry forms such as lithology , structure geology , soil and subsurface utilities condition

The effect of barite mud on the division of the detector energy window in density logging while drilling

International Nuclear Information System (INIS)

Zhang Li; Sun Jianmeng; Yu Huawei; Jiang Dong; Zhang Jing

2012-01-01

In the litho-density logging, formation density and lithology were acquired by calculating the total counts in certain energy window. Therefore, the division of the energy window directly affects the evaluation of density and lithology value. In the process of the energy window division, mud type affects the determination of the range of energy window. In this work, Monte Carlo simulation method was applied to study the range of energy window regarding to water mud and barite mud, respectively. The results show that the range of the energy window with barite mud is less than that of the water mud, and lithology identification will have greater' error in the barite mud. It is important to analyze influencing factors and improve the measurement accuracy of the litho-density logging. (authors)

Uranium migration in a sedimentological phosphatic environment in Northern Palmyrides, Al-Awabed area, Syria

International Nuclear Information System (INIS)

Asfahani, J.; Aissa, M.; Al-Hent, R.

2007-01-01

In previously published research, a factor analysis approach has been applied to airborne spectrometric data of the Al-Awabed area, Northern Palmyrides, Syria. A model of four factors (F1-F4) has proven to be sufficient to represent the acquired data, where 94% of the total data variance is explained. A scored lithological map including 11 radiometric units is established. Uranium migration trends have been determined for the first time through airborne spectrometric data of the study region, where different regional maps explaining the migration behavior have been established. A radioactive-geological model of such a migration is established and clearly shows that directions of uranium migration are strongly influenced by network drainage, topography, and fracturing systems in the region. Lithology of the 11 studied units also plays a dominant role in the rate of uranium migration. It was found that the four lithological phosphatic units P1-P4 are the main uranium sources in the study region, where the uranium migration is outward from these regions. The other seven lithological units C1-C3, M1-M4 are successively enriched by uranium during the geological evolution of the crust, where uranium migration is in an inward direction. It was also shown that uranium migration has occurred from its source for a short distance, limited by the boundaries of the lithological units which surround the phosphatic units. This finding is important from a prospecting and exploration point of view, and suggests that future uranium investigation activities are close to the phosphatic sources, if this process is creating the uranium distribution

Intrinsic vulnerability assessment of shallow aquifers of the sedimentary basin of southwestern Nigeria

Directory of Open Access Journals (Sweden)

Saheed A. Oke

2018-03-01

Full Text Available The shallow groundwater of the multi-layered sedimentary basin aquifer of southwestern Nigeria was assessed based on its intrinsic vulnerability property. The vulnerability evaluation involves determining the protective cover and infiltration condition of the unsaturated zone in the basin. This was achieved using the PI (P stands for protective cover effectiveness of the overlying lithology and I indicates the degree of infiltration bypass vulnerability method of the European vulnerability approach. The PI method specifically measures the protection cover and the degree to which the protective cover is bypassed. Intrinsic parameters assessed were the subsoil, lithology, topsoil, recharge and fracturing for the protective cover. The saturated hydraulic conductivity of topsoil, infiltration processes and the lateral surface and subsurface flow were evaluated for the infiltration bypassed. The results show moderate to very low vulnerability areas. Low vulnerability areas were characterised by lithology with massive sandstone and limestone, subsoils of sandy loam texture, high slopes and high depth to water table. The moderate vulnerability areas were characterised by high rainfall and high recharge, low water table, unconsolidated sandstones and alluvium lithology. The intrinsic vulnerability properties shown in vulnerability maps will be a useful tool in planning and monitoring land use activities that can be of impact in groundwater pollution.

Identification of dissolved-constituent sources in mine-site ground water using batch mixing

International Nuclear Information System (INIS)

Clark, G.M.; Williams, R.S. Jr.

1991-01-01

Batch-mixing experiments were used to help identify lithologic mineralogic sources of increased concentrations of dissolved solids in water affected by surface coal mining in northwestern Colorado. Ten overburden core samples were analyzed for mineral composition and mixed with distilled water for 90 days until mineral-water equilibrium was reached. Dissolved-solids concentrations ranged from 200 to 8,700 mg/L in water samples extracted from the mixtures after 90 days. Mass-balance simulations were conducted using the geochemical models BALANCE and WATEQF to quantify mineral-water interactions occurring in five selected sample mixtures and in water collected from a spring at a reclaimed mine site. The spring water is affected by mineral-water interactions occurring in all of lithologic units comprising the overburden. Results of the simulations indicate that oxidation of pyrite, dissolution of dolomite, gypsum, and epsomite, and cation-exchange reactions are the primary mineral-water interactions occurring in the overburden. Three lithologic units in the overburden probably contribute most of the dissolved solids to the spring water. Water sample extracts from mixtures using core from these three units accounted for 85 percent of the total dissolved solids in the 10 sample extracts. Other lithologic units in the overburden probably contribute smaller quantities of dissolved solids to the spring water

A geologic analysis of the Side-Looking Airborne Radar imagery of southern New England

Science.gov (United States)

Banks, Paul T.

1975-01-01

Analysis of the side looking airborn radar imagery of Massachusetts, Connecticut and Rhode Island indicates that radar shows the topography in great detail. Since bedrock geologic features are frequently expressed in the topography the radar lends itself to geologic interpretation. The radar was studied by comparisons with field mapped geologic data first at a scale of approximately 1:125,000 and then at a scale of 1:500,000. The larger scale comparison revealed that faults, minor faults, joint sets, bedding and foliation attitudes, lithology and lithologic contacts all have a topographic expression interpretable on the imagery. Surficial geologic features were far less visible on the imagery over most of the area studied. The smaller scale comparisons revealed a pervasive, near orthogonal fracture set cutting all types and ages of rock and trending roughly N40?E and N30?W. In certain places the strike of bedding and foliation attitudes and some lithologic Contacts were visible in addition to the fractures. Fracturing in southern New England is apparently far more important than has been previously recognized. This new information, together with the visibility of many bedding and foliation attitudes and lithologic contacts, indicates the importance of radar imagery in improving the geologic interpretation of an area.

Chemical analyses (raw laboratory data) and locality index maps of the Confederate Gulch area, Broadwater and Meagher Counties, Montana

Science.gov (United States)

,

1975-01-01

Analysis of the side looking airborn radar imagery of Massachusetts, Connecticut and Rhode Island indicates that radar shows the topography in great detail. Since bedrock geologic features are frequently expressed in the topography the radar lends itself to geologic interpretation. The radar was studied by comparisons with field mapped geologic data first at a scale of approximately 1:125,000 and then at a scale of 1:500,000. The larger scale comparison revealed that faults, minor faults, joint sets, bedding and foliation attitudes, lithology and lithologic contacts all have a topographic expression interpretable on the imagery. Surficial geologic features were far less visible on the imagery over most of the area studied. The smaller scale comparisons revealed a pervasive, near orthogonal fracture set cutting all types and ages of rock and trending roughly N40?E and N30?W. In certain places the strike of bedding and foliation attitudes and some lithologic Contacts were visible in addition to the fractures. Fracturing in southern New England is apparently far more important than has been previously recognized. This new information, together with the visibility of many bedding and foliation attitudes and lithologic contacts, indicates the importance of radar imagery in improving the geologic interpretation of an area.

Recent advances about of the orogenic modern belt (1000-500 M.A.) in Uruguay

International Nuclear Information System (INIS)

Bossi, J.

1989-01-01

Progress in lithologic, structural, tectonic and geo tectonic data about a 1000-500 m.y.orogenic belt developed at the East of Uruguay, arrived in the 80, are here described. Conclusions are mainly based on the 1/100.000 scale geologic map of a 6000 sq. km comprised between Sierra Ballena, Sierra de Animas, Pan de Azucar and Mariscala. These new data clearly states the lithological distribution and contribute to guide strategic prospect ion.

Dynamics of Melting and Melt Migration as Inferred from Incompatible Trace Element Abundance in Abyssal Peridotites

Science.gov (United States)

Peng, Q.; Liang, Y.

2008-12-01

To better understand the melting processes beneath the mid-ocean ridge, we developed a simple model for trace element fractionation during concurrent melting and melt migration in an upwelling steady-state mantle column. Based on petrologic considerations, we divided the upwelling mantle into two regions: a double- lithology upper region where high permeability dunite channels are embedded in a lherzolite/harzburgite matrix, and a single-lithology lower region that consists of partially molten lherzolite. Melt generated in the single lithology region migrates upward through grain-scale diffuse porous flow, whereas melt in the lherzolite/harzburgite matrix in the double-lithology region is allowed to flow both vertically through the overlying matrix and horizontally into its neighboring dunite channels. There are three key dynamic parameters in our model: degree of melting experienced by the single lithology column (Fd), degree of melting experienced by the double lithology column (F), and a dimensionless melt suction rate (R) that measures the accumulated rate of melt extraction from the matrix to the channel relative to the accumulated rate of matrix melting. In terms of trace element fractionation, upwelling and melting in the single lithology column is equivalent to non-modal batch melting (R = 0), whereas melting and melt migration in the double lithology region is equivalent to a nonlinear combination of non-modal batch and fractional melting (0 abyssal peridotite, we showed, with the help of Monte Carlo simulations, that it is difficult to invert for all three dynamic parameters from a set of incompatible trace element data with confidence. However, given Fd, it is quite possible to constrain F and R from incompatible trace element abundances in residual peridotite. As an illustrative example, we used the simple melting model developed in this study and selected REE and Y abundance in diopside from abyssal peridotites to infer their melting and melt migration

Improved predictive mapping of indoor radon concentrations using ensemble regression trees based on automatic clustering of geological units

International Nuclear Information System (INIS)

Kropat, Georg; Bochud, Francois; Jaboyedoff, Michel; Laedermann, Jean-Pascal; Murith, Christophe; Palacios, Martha; Baechler, Sébastien

2015-01-01

Purpose: According to estimations around 230 people die as a result of radon exposure in Switzerland. This public health concern makes reliable indoor radon prediction and mapping methods necessary in order to improve risk communication to the public. The aim of this study was to develop an automated method to classify lithological units according to their radon characteristics and to develop mapping and predictive tools in order to improve local radon prediction. Method: About 240 000 indoor radon concentration (IRC) measurements in about 150 000 buildings were available for our analysis. The automated classification of lithological units was based on k-medoids clustering via pair-wise Kolmogorov distances between IRC distributions of lithological units. For IRC mapping and prediction we used random forests and Bayesian additive regression trees (BART). Results: The automated classification groups lithological units well in terms of their IRC characteristics. Especially the IRC differences in metamorphic rocks like gneiss are well revealed by this method. The maps produced by random forests soundly represent the regional difference of IRCs in Switzerland and improve the spatial detail compared to existing approaches. We could explain 33% of the variations in IRC data with random forests. Additionally, the influence of a variable evaluated by random forests shows that building characteristics are less important predictors for IRCs than spatial/geological influences. BART could explain 29% of IRC variability and produced maps that indicate the prediction uncertainty. Conclusion: Ensemble regression trees are a powerful tool to model and understand the multidimensional influences on IRCs. Automatic clustering of lithological units complements this method by facilitating the interpretation of radon properties of rock types. This study provides an important element for radon risk communication. Future approaches should consider taking into account further variables

Geochemistry at the sulfate reduction-methanogenesis transition zone in an anoxic aquifer

DEFF Research Database (Denmark)

Jakobsen, Rasmus; Cold, L.

2007-01-01

The study addresses a 10 m deep phreatic postglacial sandy aquifer of vertically varying lithology and horizontally varying infiltration water chemistry, displaying calcite dissolution, ion-exchange, and anaerobic redox processes. The simple variations in lithology and infiltration combine into a...... by implementing specific energy yields for the microbial redox processes, could explain most of the observed groundwater geochemistry as an expression of a closely coupled system of mineral equilibria and redox processes occurring at partial equilibrium....

Geologic mapping using LANDSAT data

Science.gov (United States)

Siegal, B. S.; Abrams, M. J.

1976-01-01

The feasibility of automated classification for lithologic mapping with LANDSAT digital data was evaluated using three classification algorithms. The two supervised algorithms analyzed, a linear discriminant analysis algorithm and a hybrid algorithm which incorporated the Parallelepiped algorithm and the Bayesian maximum likelihood function, were comparable in terms of accuracy; however, classification was only 50 per cent accurate. The linear discriminant analysis algorithm was three times as efficient as the hybrid approach. The unsupervised classification technique, which incorporated the CLUS algorithm, delineated the major lithologic boundaries and, in general, correctly classified the most prominent geologic units. The unsupervised algorithm was not as efficient nor as accurate as the supervised algorithms. Analysis of spectral data for the lithologic units in the 0.4 to 2.5 microns region indicated that a greater separability of the spectral signatures could be obtained using wavelength bands outside the region sensed by LANDSAT.

Aerial gamma spectrometric survey as a tool for evaluating the uranium remobilization degree: Case study from Al-Awabed area, Northern Palmyrides, Syria

International Nuclear Information System (INIS)

Asfahani, J.; Al-Hent, R.; Aissa, M.

2009-01-01

The relationships between equivalent uranium (eU), eTh, K% and their ratios in the 11 lithological units determined by previous research in the Al-Awabed area, Northern Palmyrides, Syria have been analyzed in order to define their trend variations and evaluate the degree of uranium remobilization. Uranium favorability index U I and alteration-F indicators have been used in this research to characterize the different lithological units by following their radioactive element re-distribution and to determine their favorability as regards uranium potentiality. It was shown that uranium remobilization took place in all the lithological units, but to different degrees. This remobilization is qualified as weak, indicating that limited uranium redistribution is expected in the studied region. A plausible geological model is proposed for the uranium distribution, where the Abou Qila location is found to be favorable for uranium accumulation and merits further uranium exploration. (Authors)

Uranium migration in a sedimentalogical phosphatic environment in Northern Palmyrides, Al-Awabed area, Syria

International Nuclear Information System (INIS)

Asfahani, J.; Aissa, M.; Al-Hent, R.

2008-01-01

In previously published research, a factor analysis approach has been applied to airborne spectrometric data of the Al-Awabed area, Northern Palmyrides, Syria. A model of four factors (F1, F2, F3 and F4) has proven to be sufficient to represent the acquired data, where 94% of the total data variance is explained. A scored lithological map including eleven radiometric units is established. Uranium migration trends have been determined for the first time through airborne spectrometric data of the study region, where different regional maps explaining the migration behavior have been established. A radioactive geological model of such a migration is established and clearly shows that directions of uranium migration are strongly influenced by network drainage, topography and fracturing systems in the region. Lithology of the eleven studied units also plays a dominant role in the rate of uranium migration. It was found that the four lithological phosphatic units P1, P2, P3 and P4 are the main uranium sources in the study region, where the uranium migration is outward from these regions. The other seven lithological units C1, C2, C3, M1, M2, M3 and M4 are successively enriched by uranium during the geological evolution of the crust, where uranium migration is in an inward direction. It was also shown that uranium migration has occurred from its source for a short distance, limited by the boundaries of the lithological units which surround the phosphatic units. This finding is important from a prospecting and exploration point of view, and suggests future uranium investigation activities are close to the phosphatic sources, if this process is creating the uranium distribution. Al-Awabed Region. (author)

Idea of Identification of Copper Ore with the Use of Process Analyser Technology Sensors

Science.gov (United States)

Jurdziak, Leszek; Kaszuba, Damian; Kawalec, Witold; Król, Robert

2016-10-01

The Polish resources of the copper ore exploited by the KGHM S.A. underground mines are considered as one of the most complex in the world and - consequently - the most difficult to be processed. The ore consists of three lithology forms: dolomites, shales and sandstones but in different proportions which has a significant impact on the effectiveness of the grinding and flotation processes. The lithological composition of the ore is generally recognised in-situ but after being mined it is blended on its long way from various mining fields to the processing plant by the complex transportation system consisting of belt conveyors with numerous switching points, ore bunkers and shafts. Identification of the lithological composition of the ore being supplied to the processing plant should improve the adjustments of the ore processing machinery equipment aiming to decrease the specific processing (mainly grinding) energy consumption as well as increase the metal recovery. The novel idea of Process Analyser Technology (PAT) sensors - information carrying pellets, dropped into the transported or processed bulk material which can be read directly when needed - is investigated for various applications within the DISIRE project (a part of the SPIRE initiative, acting under the Horizon2020 framework program) and here is adopted for implementing the annotation the transported copper ore for the needs of ore processing plants control. The identification of the lithological composition of ore blended on its way to the processing plant can be achieved by an information system consisting of pellets that keep the information about the original location of the portions of conveyed ore, the digital, geological database keeping the data of in-situ lithology and the simulation models of the transportation system, necessary to evaluate the composition of the blended ore. The assumptions of the proposed solution and the plan of necessary in-situ tests (with the special respect to harsh

Hydrogeologic assessment of shallow clastic and carbonate rock aquifers in Hendry and Collier counties, southwestern Florida

Science.gov (United States)

Brown, C. Erwin; Krulikas, R.K.; Brendle, D.L.

1996-01-01

Direct-current electrical resistivity data were collected from 109 vertical electrical sounding sites in Hendry and Collier Counties, southwestern Florida. Selected direct-current electrical resistivity surveys, together with available borehole geologic and geophysical data, were used to determine the approximate areal extent of the shallow clastic aquifers composed of thick sands and carbonate lithologies. Results indicated that a complex pattern of shallow sands, clays, and carbonate lithologies occur throughout the area. Buried channel sands were found as deep as 50 meters below land surface in some places. The channels contain unconsolidated fine- to medium-grained quartz sand interbedded with sandy limestone, shell fragments, and gray-green sandy clay. Both surface and borehole geophysical techniques with lithologic data were necessary to approximately locate and define layers that might behave as confining layers and to locate and define the extent of any buried sand aquifers. The borehole geophysical data were used to analyze the zones of higher resistivity. Direct-current electrical resistivity data indicated the approximate location of certain layer boundaries. The conjunctive use of natural gamma and short- and long-normal resistivity logs was helpful in determining lithologic effects. Geohydrologic sections were prepared to identify potential locations of buried channels and carbonates containing freshwater. Buried channel sands and carbonate rock sections were identified in the subsurface that potentially may contain freshwater supplies.

Characterisation of weathered clayey soils responsible for shallow landslides

Directory of Open Access Journals (Sweden)

C. Meisina

2006-01-01

Full Text Available Shallow earth translational slides and earth flows, affecting colluvial soils derived by the weathering of the clayey bedrock, are a recurrent problem causing damage to buildings and roads in many areas of Apennines. The susceptibility assessment, e.g. slope stability models, requires the preliminary characterization of these superficial covers (lithology, geotechnical and hydraulic parameters. The aim of the work is to develop and test a methodology for the identification and mapping of weathered clayey soils responsible for shallow landslides. A test site in Northern Apennines (Province of Pavia was selected. Argillaceous and marly successions characterize the area. Shallow landslides occurred periodically due to high intensity rainfalls. Trench pits were used for the soil profile description (lithology, structure, grade of weathering, thickness and sampling. The main geological, topographic and geomorphologic parameters of shallow landslides were analysed. Field surveys were integrated with some geotechnical laboratory tests (index properties, suction and volumetric characteristic determination, methylene blue adsorption test, linear shrinkage, swell strain. Engineering geological zoning was carried out by grouping the superficial soils on the basis of the following attributes: topographic conditions (slope angle, landslide occurrence, lithology (grain size, geometry (thickness, lithology of the bedrock, hydrogeological and geotechnical characteristics. The resulting engineering-geological units (areas that may be regarded as homogeneous from the geomorphologic and engineering – geological point of view were analysed in terms of shallow slope instability.

Mapping rock forming minerals at Boundary Canyon, Death Valey National Park, California, using aerial SEBASS thermal infrared hyperspectral image data

Science.gov (United States)

Aslett, Zan; Taranik, James V.; Riley, Dean N.

2018-02-01

Aerial spatially enhanced broadband array spectrograph system (SEBASS) long-wave infrared (LWIR) hyperspectral image data were used to map the distribution of rock-forming minerals indicative of sedimentary and meta-sedimentary lithologies around Boundary Canyon, Death Valley, California, USA. Collection of data over the Boundary Canyon detachment fault (BCDF) facilitated measurement of numerous lithologies representing a contact between the relatively unmetamorphosed Grapevine Mountains allochthon and the metamorphosed core complex of the Funeral Mountains autochthon. These included quartz-rich sandstone, quartzite, conglomerate, and alluvium; muscovite-rich schist, siltstone, and slate; and carbonate-rich dolomite, limestone, and marble, ranging in age from late Precambrian to Quaternary. Hyperspectral data were reduced in dimensionality and processed to statistically identify and map unique emissivity spectra endmembers. Some minerals (e.g., quartz and muscovite) dominate multiple lithologies, resulting in a limited ability to differentiate them. Abrupt variations in image data emissivity amongst pelitic schists corresponded to amphibolite; these rocks represent gradation from greenschist- to amphibolite-metamorphic facies lithologies. Although the full potential of LWIR hyperspectral image data may not be fully utilized within this study area due to lack of measurable spectral distinction between rocks of similar bulk mineralogy, the high spectral resolution of the image data was useful in characterizing silicate- and carbonate-based sedimentary and meta-sedimentary rocks in proximity to fault contacts, as well as for interpreting some mineral mixtures.

Lithology and surficial sediment distribution: northern Hatteras Abyssal Plain

International Nuclear Information System (INIS)

Dickson, S.M.; Laine, E.P.; Friedrich, N.E.

1985-01-01

Surficial sediments of the LLWODP study area E-N3 have several common characteristics and a few anomalous features. All of the 26 surficial samples examined are Holocene in age. In E-N3, the Holocene sequence ranges from 12-90 cm. The sequence is composed primarily of brown foraminiferal lutite. The lutites show evidence of burrowing by benthic animals in the form of burrows infilled with sediment of a different color. Below the bioturbated lutites is a dark brown, iron-enriched horizon stratigraphically near (within a few centimeters of) the Pleistocene/Holocene boundary. The vertical extent of this unit, which ranges from 2-22 cm, varies systematically within the study area. The maximum thickness is found in a region most removed from the terrigenous sediment entry points. Fine-grained turbidity currents, an abyssal current, and a debris flow created the uncommon features of the surficial sediments. The areal extent of these deposits is estimated as 10% of the E-N3 region below 5300 m. The largest turbidite is probably greater than 2000 km 2 in extent. However, evidence of coarse-grained turbidity current activity in the Holocene is absent. Hemipelagic deposition during the Holocene has resulted in a texturally uniform sequence of surficial sediments. 22 references, 10 figures, 6 tables

Fluid Assisted Compaction and Deformation of Reservoir Lithologies; FINAL

International Nuclear Information System (INIS)

Kronenberg, A.K.; Chester, F.M.; Chester, J.S.; Hajash, A.; He, W.; Karner, S.; Lenz, S.

2002-01-01

The compaction and diagenesis of sandstones that form reservoirs to hydrocarbons depend on mechanical compaction processes, fluid flow at local and regional scales, and chemical processes of dissolution, precipitation and diffusional solution transport. The compaction and distortional deformation of quartz aggregates exposed to reactive aqueous fluids have been investigated experimentally at varying critical and subcritical stress states and time scales. Pore fluid compositions and reaction rates during deformation have been measured and compared with creep rates. Relative contributions of mechanical and chemical processes to deformation and pore structure evolution have been evaluated using acoustic emission (AE) measurements and scanning electron microscope (SEM) observations. At the subcritical conditions investigated, creep rates and acoustic emission rates fit transient logarithmic creep laws. Based on AE and SEM observations, we conclude that intragranular cracking and grain rearrangement are the dominant strain mechanisms. Specimens show little evidence of stress-enhanced solution transfer. At long times under wet conditions, the dominant strain mechanism gradually shifts from critical cracking at grain contacts with high stress concentrations to fluid-assisted sub-critical cracking

Lithological and Structural Controls on the Development of Aquifer ...

African Journals Online (AJOL)

Bheema

Research Article ... Based on borehole and structure data presence of multilayer aquifers, their .... Shape of the clasts varies from angular, elliptical and ..... Water quality investigation (i.e. for domestic purpose) is also recommended. 6.

Lithology and economic potential resource of Igumale-Nsukka area ...

African Journals Online (AJOL)

The sandstones are used in the manufacturing of glass while laterites are used for various construction purposes such as roads, buildings and bridges. The clays are for pottery, glazed tiles, in ceramics industry. The coal has a future prospect for industries, such as iron and steel industry as cooking coal, cement industries ...

lithologic characterisation of the basement aquifers of awe and ...

African Journals Online (AJOL)

Global Journal

resistivity exceeded 3000 ohm-m, then the bedrock is fresh and prospect for water is low (Olayinka and. Olorunfemi, 1992; Olorunfemi and Olorunniwo, 1990). Groundwater zones are found in the weathered and fractured zones in basement areas. In Ibarapa area of SW, Nigeria the associated fractured bedrock aquifers.

Geologic mapping of near-surface sediments in the northern Mississippi Embayment, McCracken County, KY

Energy Technology Data Exchange (ETDEWEB)

Sexton, Joshua L [JL Sexton and Son; Fryar, Alan E [Dept of Earth and Geoligical Sciences, Univ of KY,; Greb, s F [Univ of KY, KY Geological Survey

2006-04-01

POSTER: The Jackson Purchase region of western Kentucky consists of Coastal Plain sediments near the northern margin of the Mississippi Embayment. Within this region is the Paducah Gaseous Diffusion Plant (PGDP), a uranium enrichment facility operated by the US Department of Energy. At PGDP, a Superfund site, soil and groundwater studies have provided subsurface lithologic data from hundreds of monitoring wells and borings. Despite preliminary efforts by various contractors, these data have not been utilized to develop detailed stratigraphic correlations of sedimentary units across the study area. In addition, sedimentary exposures along streams in the vicinityof PGDP have not been systematically described beyond the relatively simple geologic quadrangle maps published by the US Geological Survey in 1966-67. This study integrates lithologic logs, other previous site investigation data, and outcrop mapping to provide a compilation of near-surface lithologic and stratigraphic data for the PGDP area. A database of borehole data compiled during this study has been provided to PGDP for future research and archival.

Mineralogy and petrogenesis of lunar magnesian granulitic meteorite Northwest Africa 5744

Science.gov (United States)

Kent, Jeremy J.; Brandon, Alan D.; Joy, Katherine H.; Peslier, Anne H.; Lapen, Thomas J.; Irving, Anthony J.; Coleff, Daniel M.

2017-09-01

Lunar meteorite Northwest Africa (NWA) 5744 is a granulitic breccia with an anorthositic troctolite composition that may represent a distinct crustal lithology not previously described. This meteorite is the namesake and first-discovered stone of its pairing group. Bulk rock major element abundances show the greatest affinity to Mg-suite rocks, yet trace element abundances are more consistent with those of ferroan anorthosites. The relatively low abundances of incompatible trace elements (including K, P, Th, U, and rare earth elements) in NWA 5744 could indicate derivation from a highlands crustal lithology or mixture of lithologies that are distinct from the Procellarum KREEP terrane on the lunar nearside. Impact-related thermal and shock metamorphism of NWA 5744 was intense enough to recrystallize mafic minerals in the matrix, but not intense enough to chemically equilibrate the constituent minerals. Thus, we infer that NWA 5744 was likely metamorphosed near the lunar surface, either as a lithic component within an impact melt sheet or from impact-induced shock.

A rapid screening-level method to optimize location of infiltration ponds.

Science.gov (United States)

Fennemore, G G; Davis, A; Goss, L; Warrick, A W

2001-01-01

A rapid-screening technique was developed to identify lithologies that best disperse artificial recharge via surface infiltration and minimize effects on ground water chemistry. The technique prospectively evaluates basin infiltration rates and water chemistry influences by integrating geotechnical, hydraulic, and water quality data with column test data and numerical modeling. The technique was validated using field data collected from surface infiltration basins designed to recharge ground water pumped from the Pipeline pit gold mine in Nevada. Observed recharge rates at these infiltration sites correlated most significantly with depth to groundwater, with basins in coarse-grained lithologies performing better (0.45 to 0.85 m/day) than those with fine-grained layers ( 2000 mg/L) than coarse-grained soils (infiltration basins for a variety of lithologies. Sites for infiltration basins can be rapidly screened to include areas with greatest depth to groundwater and in coarsest alluvial sediments, and impact to ground water chemistry can be reliably predicted using computer modeling and column test results.

Rim Structure, Stratigraphy, and Aqueous Alteration Exposures Along Opportunity Rover's Traverse of the Noachian Endeavour Crater

Science.gov (United States)

Crumpler, L.S.; Arvidson, R. E.; Golombek, M.; Grant, J. A.; Jolliff, B. L.; Mittlefehldt, D. W.

2017-01-01

The Mars Exploration Rover Opportunity has traversed 10.2 kilometers along segments of the west rim of the 22-kilometer-diameter Noachian Endeavour impact crater as of sol 4608 (01/09/17). The stratigraphy, attitude of units, lithology, and degradation state of bedrock outcrops exposed on the crater rim have been examined in situ and placed in geologic context. Structures within the rim and differences in physical properties of the identified lithologies have played important roles in localizing outcrops bearing evidence of aqueous alteration.

Area of Interest 1, CO₂ at the Interface. Nature and Dynamics of the Reservoir/Caprock Contact and Implications for Carbon Storage Performance

Energy Technology Data Exchange (ETDEWEB)

Mozley, Peter [New Mexico Institute Of Mining And Technology, Socorro, NM (United States); Evans, James [New Mexico Institute Of Mining And Technology, Socorro, NM (United States); Dewers, Thomas [New Mexico Institute Of Mining And Technology, Socorro, NM (United States)

2014-10-31

We examined the influence of geologic features present at the reservoir/caprock interface on the transmission of supercritical CO₂ into and through caprock. We focused on the case of deformation-band faults in reservoir lithologies that intersect the interface and transition to opening-mode fractures in caprock lithologies. Deformation-band faults are exceeding common in potential CO₂ injection units and our fieldwork in Utah indicates that this sort of transition is common. To quantify the impact of these interface features on flow and transport we first described the sedimentology and permeability characteristics of selected sites along the Navajo Sandstone (reservoir lithology) and Carmel Formation (caprock lithology) interface, and along the Slickrock Member (reservoir lithology) and Earthy Member (caprock lithology) of the Entrada Sandstone interface, and used this information to construct conceptual permeability models for numerical analysis. We then examined the impact of these structures on flow using single-phase and multiphase numerical flow models for these study sites. Key findings include: (1) Deformation-band faults strongly compartmentalize the reservoir and largely block cross-fault flow of supercritical CO₂. (2) Significant flow of CO₂ through the fractures is possible, however, the magnitude is dependent on the small-scale geometry of the contact between the opening-mode fracture and the deformation band fault. (3) Due to the presence of permeable units in the caprock, caprock units are capable of storing significant volumes of CO₂, particularly when the fracture network does not extend all the way through the caprock. The large-scale distribution of these deformation-bandfault-to-opening-mode-fractures is related to the curvature of the beds, with greater densities of fractures in high curvature regions. We also examined core and outcrops from the Mount Simon Sandstone and Eau Claire

Geologic-seismic models, prediction of shallow-water lacustrine delta sandbody and hydrocarbon potential in the Late Miocene, Huanghekou Sag, Bohai Bay Basin, northern China

Directory of Open Access Journals (Sweden)

Hao Liu

2018-01-01

Full Text Available The Huanghekou Sag is located at the southeast part of the Bohai Bay Basin, northern China. Large-scale shallow lake delta developed in the Neogene provided suitable geological conditions for the formation of a subtle oil-gas reservoir in this area. The key for analyzing sandstone reservoir and sedimentary facies is by using seismic attributes (amplitude to establish the relationship between lithology combination and seismic attributes. The lower unit of Late Miocene Minghuazhen Formation at the BZ34 block in the Huanghekou Sag was subdivided into 10 parasequence sets (PSS. Thicker sandstones mainly occurred in PSS1 and PSS10, whereas thin sandstones are mostly observed within other parasequence sets. This study presents statistics and analyses of lithology, i.e., statistics of root-mean-square (RMS amplitude and lithology of well locations in different parasequence sets of the study area, as well as 1-D forward seismic models of 7 types of lithology combinations, the establishment of a spatial distribution of 2-D sandbody, forward seismic models etc. Our study indicates that high amplitude peaks correspond to thicker sandbodies, while low amplitude indicates non-development of sandbodies (generally less than 2 m, and medium amplitude agrees well with large sets of mudstones interbedded with medium and thinner sandstones. Different sand–mudstone combinations genetically reflect a combination of multiple micro-facies, therefore, amplitude features can predict sandbodies as well as facies characteristics.

Identification of dissolved-constituent sources in mine-site ground water using batch mixing

Science.gov (United States)

Clark, Gregory M.; Williams, Robert S.

1991-01-01

Batch-mixing experiments were used to help identify lithologic and mineralogic sources of increased concentrations of dissolved solids in water affected by surface coal mining in northwestern Colorado. Ten overburden core samples were analyzed for mineral composition and mixed with distilled water for 90 days until mineral-water equilibrium was reached. Between one day and 90 days after initial contact, specific conductance in the sample mixtures had a median increase of 306 percent. Dissolved-solids concentrations ranged from 200 to 8,700 mg/L in water samples extracted from the mixtures after 90 days. Mass-balance simulations were conducted using the geochemical models BALANCE and WATEQF to quantify mineral-water interactions occurring in five selected sample mixtures and in water collected from a spring at a reclaimed mine site. The spring water is affected by mineral-water interactions occurring in all of the lithologic units comprising the overburden. Results of the simulations indicate that oxidation of pyrite, dissolution of dolomite, gypsum, and epsomite, and cation-exchange reactions are the primary mineral-water interactions occurring in the overburden. Three lithologic units in the overburden (a coal, a sandstone, and a shale) probably contribute most of the dissolved solids to the spring water. Water sample extracts from mixtures using core from these three units accounted for 85 percent of the total dissolved solids in the 10 sample extracts. Other lithologic units in the over-burden probably contribute smaller quantities of dissolved solids to the spring water.

Reducing Uncertainties in Hydrocarbon Prediction through Application of Elastic Domain

Science.gov (United States)

Shamsuddin, S. Z.; Hermana, M.; Ghosh, D. P.; Salim, A. M. A.

2017-10-01

The application of lithology and fluid indicators has helped the geophysicists to discriminate reservoirs to non-reservoirs from a field. This analysis is conducted to select the most suitable lithology and fluid indicator for the Malaysian basins that could lead to better eliminate pitfalls of amplitude. This paper uses different rock physics analysis such as elastic impedance, Lambda-Mu-Rho, and SQp-SQs attribute. Litho-elastic impedance log is generated by correlating the gamma ray log with extended elastic impedance log. The same application is used for fluid-elastic impedance by correlation of EEI log with water saturation or resistivity. The work is done on several well logging data collected from different fields in Malay basin and its neighbouring basin. There's an excellent separation between hydrocarbon sand and background shale for Well-1 from different cross-plot analysis. Meanwhile, the Well-2 shows good separation in LMR plot. The similar method is done on the Well-3 shows fair separation of silty sand and gas sand using SQp-SQs attribute which can be correlated with well log. Based on the point distribution histogram plot, different lithology and fluid can be separated clearly. Simultaneous seismic inversion results in acoustic impedance, Vp/Vs, SQp, and SQs volumes. There are many attributes available in the industry used to separate the lithology and fluid, however some of the methods are not suitable for the application to the basins in Malaysia.

Laboratory measurements of the seismic velocities and other petrophysical properties of the Outokumpu deep drill core samples, eastern Finland

Science.gov (United States)

Elbra, Tiiu; Karlqvist, Ronnie; Lassila, Ilkka; Høgström, Edward; Pesonen, Lauri J.

2011-01-01

Petrophysical, in particular seismic velocity, measurements of the Outokumpu deep drill core (depth 2.5 km) have been carried out to characterize the geophysical nature of the Paleoproterozoic crustal section of eastern Finland and to find lithological and geophysical interpretations to the distinct crustal reflectors as observed in seismic surveys. The results show that different lithological units can be identified based on the petrophysical data. The density of the samples remained nearly constant throughout the drilled section. Only diopside-tremolite skarns and black schists exhibit higher densities. The samples are dominated by the paramagnetic behaviour with occasional ferromagnetic signature caused by serpentinitic rocks. Large variations in seismic velocities, both at ambient pressure and under in situ crustal conditions are observed. The porosity of the samples, which is extremely low, is either intrinsic by nature or caused by decompaction related to fracturing during the core retrieval. It is noteworthy that these microfractures have dramatically lowered the VP and VS values. From the measured velocities and density data we have calculated the seismic impedances, Young's modulus and Poisson's ratios for the lithological units of the Outokumpu section and from these data the reflection coefficients for the major lithological boundaries, evident in the surveyed section, were determined. The data show that the strong and distinct reflections visible in wide-angle seismic surveys are caused by interfaces between diopside-tremolite skarn and either serpentinites, mica schist or black schist.

The source rock characters of U-rich granite

Energy Technology Data Exchange (ETDEWEB)

Mingyue, Feng; Debao, He [CNNC Key Laboratory of Uranium Resources Exploration and Evaluation Technology, Beijing Research Institute of Uranium Geology (China)

2012-03-15

This paper discusses the stratum composition, lithological association, uranium content of crust and the activation, migration, concentration of uranium at each tectonic cycle in South China. The authors point out that the source rock of U-rich granite is U-rich continental crust which is rich in Si, Al and K. The lithological association is mainly composed of terrestrial clastic rocks formation of mudstone and sandstone, mingled with intermediate-acidic, mafic pyroclastic rocks and carbonate rocks formation. During tectonic movements, the rocks had undergone regional metamorphism, migmatitization, granitization, and formed U-rich granites finally. (authors)

The source rock characters of U-rich granite

International Nuclear Information System (INIS)

Feng Mingyue; He Debao

2012-01-01

This paper discusses the stratum composition, lithological association, uranium content of crust and the activation, migration, concentration of uranium at each tectonic cycle in South China. The authors point out that the source rock of U-rich granite is U-rich continental crust which is rich in Si, Al and K. The lithological association is mainly composed of terrestrial clastic rocks formation of mudstone and sandstone, mingled with intermediate-acidic, mafic pyroclastic rocks and carbonate rocks formation. During tectonic movements, the rocks had undergone regional metamorphism, migmatitization, granitization, and formed U-rich granites finally. (authors)

Geothermal well log interpretation midterm report

Energy Technology Data Exchange (ETDEWEB)

Sanyal, S.K.; Wells, L.E.; Bickham, R.E.

1979-02-01

Reservoir types are defined according to fluid phase and temperature, lithology, geologic province, pore geometry, and salinity and fluid chemistry. Improvements are needed in lithology and porosity definition, fracture detection, and thermal evaluation for more accurate interpretation. Further efforts are directed toward improving diagnostic techniques for relating rock characteristics and log response, developing petrophysical models for geothermal systems, and developing thermal evaluation techniques. The Geothermal Well Log Interpretation study and report has concentrated only on hydrothermal geothermal reservoirs. Other geothermal reservoirs (hot dry rock, geopressured, etc.) are not considered.

Soil gas radon concentration across faults near Caracas, Venezuela

International Nuclear Information System (INIS)

Sajo-Bohus, L.; Flores, N.; Urbani, F.; Carreno, R.

2001-01-01

SSNTD were used across tectonic features of different degree of activity and lithology in four localities north of Caracas, Venezuela. The homemade dosimeters with LR115 film were buried 20-30 cm in the ground. This cheap and low- tech method proved very useful to understand the tectonic features involved, measuring higher Radon concentration above traces of active faults while in old and sealed faults the results only show the effect of the surrounding lithology. Radon concentration range is 4.3 - 27.2 kB/m 3 . (Author)

SNG-logs at the Bagsvaerd Lake

International Nuclear Information System (INIS)

Korsbech, U.

1992-11-01

Spectral Natural Gamma-logs (SNG) were taken in old boreholes around Bagsvaerd Lake (Zealand). The purpose of this investigation was to clarify the geologic/lithologic conditions in this region and the potential risks of waste penetration into ground water. Relationship curves for thorium, uranium and potassium concentrations are given. Some special logs which can be useful for evaluating concentration variations or transition forms among various lithological layers are collected. Appendices contain technical information on the boreholes and discussion of differences between results of SNG-logging and the conventional gamma-logging. (EG)

Trace fossils of a cyclic chalk-marl succession; the upper Maastrichtian Rørdal Member, Denmark

DEFF Research Database (Denmark)

Lauridsen, Bodil Wesenberg; Surlyk, Finn; Bromley, Richard Granville

2011-01-01

Trace fossils from an upper Maastrichtian cyclic chalk–marl succession, the Rørdal Member, exposed in the Rørdal quarry, Denmark, are analysed in order to test whether the changes in substrate lithology exerted any control over the ichnodiversity, tiering complexity, and density of the infauna...... in the visibility of traces between chalk and marl and not due to differences in ecological stress upon the endobenthic community of the two lithologies. The study thus provides an excellent example of how the effect of taphonomic factors may give a misleading and biased impression of apparent differences...

Elemental, isotopic, and structural changes in Tagish Lake insoluble organic matter produced by parent body processes

Science.gov (United States)

Alexander, C. M. O'd.; Cody, G. D.; Kebukawa, Y.; Bowden, R.; Fogel, M. L.; Kilcoyne, A. L. D.; Nittler, L. R.; Herd, C. D. K.

2014-04-01

Here, we present the results of a multitechnique study of the bulk properties of insoluble organic material (IOM) from the Tagish Lake meteorite, including four lithologies that have undergone different degrees of aqueous alteration. The IOM C contents of all four lithologies are very uniform and comprise about half the bulk C and N contents of the lithologies. However, the bulk IOM elemental and isotopic compositions vary significantly. In particular, there is a correlated decrease in bulk IOM H/C ratios and δD values with increasing degree of alteration—the IOM in the least altered lithology is intermediate between CM and CR IOM, while that in the more altered lithologies resembles the very aromatic IOM in mildly metamorphosed CV and CO chondrites, and heated CMs. Nuclear magnetic resonance (NMR) spectroscopy, C X-ray absorption near-edge (XANES), and Fourier transform infrared (FTIR) spectroscopy confirm and quantitate this transformation from CR-like, relatively aliphatic IOM functional group chemistry to a highly aromatic one. The transformation is almost certainly thermally driven, and probably occurred under hydrothermal conditions. The lack of a paramagnetic shift in 13C NMR spectra and 1s-σ* exciton in the C-XANES spectra, both typically seen in metamorphosed chondrites, shows that the temperatures were lower and/or the timescales were shorter than experienced by even the least metamorphosed type 3 chondrites. Two endmember models were considered to quantitatively account for the changes in IOM functional group chemistry, but the one in which the transformations involved quantitative conversion of aliphatic material to aromatic material was the more successful. It seems likely that similar processes were involved in producing the diversity of IOM compositions and functional group chemistries among CR, CM, and CI chondrites. If correct, CRs experienced the lowest temperatures, while CM and CI chondrites experienced similar more elevated temperatures

Reactive transport in a partially molten system with binary solid solution

Science.gov (United States)

Jordan, J.; Hesse, M. A.

2017-12-01

Melt extraction from the Earth's mantle through high-porosity channels is required to explain the composition of the oceanic crust. Feedbacks from reactive melt transport are thought to localize melt into a network of high-porosity channels. Recent studies invoke lithological heterogeneities in the Earth's mantle to seed the localization of partial melts. Therefore, it is necessary to understand the reaction fronts that form as melt flows across the lithological interface of a heterogeneity and the background mantle. Simplified melting models of such systems aide in the interpretation and formulation of larger scale mantle models. Motivated by the aforementioned facts, we present a chromatographic analysis of reactive melt transport across lithological boundaries, using theory for hyperbolic conservation laws. This is an extension of well-known linear trace element chromatography to the coupling of major elements and energy transport. Our analysis allows the prediction of the feedbacks that arise in reactive melt transport due to melting, freezing, dissolution and precipitation for frontal reactions. This study considers the simplified case of a rigid, partially molten porous medium with binary solid solution. As melt traverses a lithological contact-modeled as a Riemann problem-a rich set of features arise, including a reacted zone between an advancing reaction front and partial chemical preservation of the initial contact. Reactive instabilities observed in this study originate at the lithological interface rather than along a chemical gradient as in most studies of mantle dynamics. We present a regime diagram that predicts where reaction fronts become unstable, thereby allowing melt localization into high-porosity channels through reactive instabilities. After constructing the regime diagram, we test the one-dimensional hyperbolic theory against two-dimensional numerical experiments. The one-dimensional hyperbolic theory is sufficient for predicting the

Geological model of the Olkiluoto site Version O

International Nuclear Information System (INIS)

Paulamaeki, S.; Paananen, M.; Gehoer, S.

2006-05-01

The geological model of the Olkiluoto site consists of four submodels: the lithological model, the ductile deformation model, the brittle deformation model and the alteration model. The lithological model gives properties of definite rock units that can be defined on the basis the migmatite structures, textures and modal compositions. The ductile deformation model describes and models the products of polyphase ductile deformation, which enables to define the dimensions and geometrical properties of individual lithological units determined in the lithological model. The brittle deformation model describes the products of multiple phases of brittle deformation. The alteration model describes the types, occurrence and the effects of the hydrothermal alteration. The rocks of Olkiluoto can be divided into two major classes: (1) supracrustal high-grade metamorphic rocks including various migmatitic gneisses, tonalitic-granodioriticgranitic gneisses, mica gneisses, quartz gneisses and mafic gneisses, and (2) igneous rocks including pegmatitic granites and diabase dykes. The migmatitic gneisses can further be divided into three subgroups in terms of the type of migmatite structure: veined gneisses, stromatic gneisses and diatexitic gneisses. On the basis of refolding and crosscutting relationships, the metamorphic supracrustal rocks have been subject to polyphased ductile deformation, including five stages. In 3D modelling of the lithological units, an assumption has been made, on the basis of measurements in outcrops, investigation trenches and drill cores, that the pervasive, composite foliation produced as a result a polyphase ductile deformation has a rather constant attitude in the ONKALO area. Consequently, the strike and dip of the foliation has been used as a tool, through which the lithologies have been correlated between the drillholes and from the surface to the drillholes. The bedrock in the Olkiluoto site has been subject to extensive hydrothermal alteration

A Dynamic study of Mantle processes applying In-situ Methods to Compound Xenoliths: implications for small to intermediate scale heterogeneity

Science.gov (United States)

Baziotis, Ioannis; Asimow, Paul; Koroneos, Antonios; Ntaflos, Theodoros; Poli, Giampero

2013-04-01

The mantle is the major geochemical reservoir of most rock-forming elements in the Earth. Convection and plate-tectonic driven processes act to generate local and regional heterogeneity within the mantle, which in turn through thermal and chemical interactions modulates ongoing geophysical processes; this feedback shapes the dynamics of the deep interior. Consequently, these processes contribute to the evolution of the earth throughout its geological history. Up to now, the heterogeneity of the mantle has been extensively studied in terms of conventional methods using basalt chemistry, bulk rock and mineral major and trace element analysis of isolated xenolith specimens of varying lithology, and massif exposures. The milestone of the present study, part of an ongoing research project, is the application of in-situ analytical methods such as microprobe, LA-ICP-MS and high resolution SEM in order to provide high quality major and trace element analyses as well as elemental distribution of the coexisting phases in the preserved intra-mantle lithologies, Particularly, in the context of the current study we used selected compound xenoliths from San Carlos (Arizona, USA), Kilbourne Hole (New Mexico, USA), Cima Dome and Dish Hill suites (California, USA), San Quintin (Baja California, Mexico) and Chino Valley (Arizona, USA), from the Howard Wilshire collection archived at the Smithsonian Institution. The selection of these compound xenoliths was based upon freshness and integrity of specimens, maximum distance on both sides of lithologic contacts, and rock types thought most likely to represent subsolidus juxtaposition of different lithologies that later partially melted in contact. The San Carlos samples comprise composite xenoliths with websterite, lherzolite and clinopyroxenite layers or clinopyroxenite veins surrounded by lherzolite or orthopyroxenite-rich rims. The Kilbourne Hole suite comprises spinel-(olivine) clinopyroxenite and orthopyroxenite dikes cutting

Slope stability probability classification, Waikato Coal Measures, New Zealand

Energy Technology Data Exchange (ETDEWEB)

Lindsay, P.; Campbell, R.; Fergusson, D.A.; Ferm, J.C.; Gillard, G.R.; Moore, T.A. [CRL Energy Ltd., Christchurch (New Zealand)

1999-07-01

Ferm classified lithological units have been identified and described in the Waikato Coal Measures in open pits in the Waikato coal region. These lithological units have been classified geotechnically with mechanical tests and discontinuity measurements. Using these measurements, slope stability probability classification (SSPC) have been quantified based on an adaption of Hack's SSPC system which places less influence on rock quality designation and unconfined compressive strength than previous rock mass rating systems. An attempt has been made to modify the Hack weathering susceptibility rating by using chemical index of alteration values from XRF major element analysis. Another major component of this adapted SSPC system is the inclusion of rock moisture content effects on slope stability. The paper explains the systematic initial approach of using the adapted SSPC system to classify slope stability in the Waikato open pit coal mines. The XRF major element results obtained for lithologies in the Waikato coal region may be a useful mine management tool to quantify stratigraphic thickness and palaeoweathering from wash drill cuttings. 14 refs., 7 figs., 3 tabs.

Interpretasi Struktur Bawah Tanah pada Sistem Sungai Bribin dengan Metode Geo

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Khafidh Nur Aziz

2016-09-01

Full Text Available This research was aimed to determine the distribution pattern of magnetic field anomaly and to identify the lithology of underground structure in Bribin Karst using geomagnetic method. Research location was Semanu Sub-district, Gunungkidul Regency at UTM coordinate of 464061 mT-464929 mT and 9111097 mU-9111970 mU. The data were taken using G-5 Proton Precession Magnetometer (PPM by looping method. The result showed that the distribution pattern of the magnetic field anomaly in Karst Bribin has value of 330 nT - 530 nT and anomaly values reflecting the system of Bribin River has value of 400 nT-460 nT. The lithology of underground structure in Karst Bribin has susceptibility value of -0.069 (in SI - 0.0661 (in SI with depth 200 m associated with limestone, tuff, gypsum, rock salt, and minerals calcite and anhydrite and the lithology associated with the system of Bribin River has susceptibility value -0.069 (in SI associated with gypsum, rock salt, and minerals anhydrite.

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

Role of different types of solid models in hydrodynamic modeling and their effects on groundwater protection processes

Science.gov (United States)

Bódi, Erika; Buday, Tamás; McIntosh, Richard William

2013-04-01

Defining extraction-modified flow patterns with hydrodynamic models is a pivotal question in preserving groundwater resources regarding both quality and quantity. Modeling is the first step in groundwater protection the main result of which is the determination of the protective area depending on the amount of extracted water. Solid models have significant effects on hydrodynamic models as they are based on the solid models. Due to the legislative regulations, on protection areas certain restrictions must be applied which has firm consequences on economic activities. In Hungarian regulations there are no clear instructions for the establishment of either geological or hydrodynamic modeling, however, modeling itself is an obligation. Choosing the modeling method is a key consideration for further numerical calculations and it is decisive regarding the shape and size of the groundwater protection area. The geometry of hydrodynamic model layers is derived from the solid model. There are different geological approaches including lithological and sequence stratigraphic classifications furthermore in the case of regional models, formation-based hydrostratigraphic units are also applicable. Lithological classification is based on assigning and mapping of lithotypes. When the geometry (e.g. tectonic characteristics) of the research area is not known, horizontal bedding is assumed the probability of which can not be assessed based on only lithology. If the geological correlation is based on sequence stratigraphic studies, the cyclicity of sediment deposition is also considered. This method is more integrated thus numerous parameters (e.g. electrofacies) are taken into consideration studying the geological conditions ensuring more reliable modeling. Layers of sequence stratigraphic models can be either lithologically homogeneous or they may include greater cycles of sediments containing therefore several lithological units. The advantage of this is that the modeling can

How steep are the Alps?

Science.gov (United States)

Robl, Jörg; Prasicek, Günther; Stüwe, Kurt; Hergarten, Stefan

2014-05-01

The topography of the European Alps reflects continental collision, crustal thickening and buoyancy driven surface uplift, overprinted by erosional processes. Topographic gradients generally steepen from the valley floors up to about 1500 m - 2000 m followed by an unexpected decrease in slope up to about 2900 m and a further increase to the highest summits of the range. Several studies have interpreted this pattern and the accompanied maximum in the hypsometric curve in terms of either the critical slope stability angle, the prematurity of the Alps caused by recent tectonic uplift, or the effect of the glacial "buzz saw" related to the Pleistocene glaciation cycles. There is consensus that the lithological inventory represents a first order parameter for the steepness of fluvial channels and the angle of hillslopes in steady state and that the response time of a transient landscape is controlled by lithology. In this study we systematically explore the slope-elevation distributions for several hundred continuous domains of the major structural units of the Alps. For this, we apply a novel numerical code to determine the predominant cause for the observed peculiar topography. We compare adjacent alpine domains with contrasting lithology to explore lithological effects on the limiting slope stability angle. We analyze domains with different lithology in the non-glaciated parts of the orogen to highlight the state of maturity related to a recent uplift event. We evaluate the glacial effects on the landscape by the comparison of areas belonging to the same structural units but affected by a variable amount of glacial imprint. The results show that lithology has a major impact on the morphometric characteristics of the European Alps. Adjacent but different structural units show a significant variability in their slope-elevation distributions although they have experienced the same uplift history and the same amount of glacial imprint. This suggests that the response

An examination of the factors governing the development of karst topography in the Cumberland Valley of Pennsylvania

International Nuclear Information System (INIS)

Ackerman, R.V.

1993-01-01

The landscape of the Cumberland Valley of South Central Pennsylvania is dominated by karst topography. A study was initiated to determine if the development of karst was controlled primarily by geologic structure or by lithologic differences. Existing data concerning the geographic locations of karst features, the hydrogeologic characteristics of the Cumberland Valley, and the chemistry of the eleven carbonate formations within the 518 km 2 study area were compiled. Data concerning 366 mapped sinkholes and over 9,000 additional karst features and their relations to the structural, lithological and spatial characteristics of the study area were collected and compiled into the database. Other factors contributing to karst development such as groundwater flow, soil and colluvium characteristics, and geographic distribution were considered. The data suggest that structure dominates lithology in the development of karst features within the study area. Structural features such as fractures, joints and folds, which create secondary porosity, are prerequisite for solution of the carbonate bedrock. Joint systems, fold axes, igneous intrusions, caves, springs and groundwater flow have a significant impact on the development of karst features. The presence of faults proved inconclusive. There are a greater number of karst features per unit area in areas of purer limestones (units with a lower percentage of acid insoluble residue). Lithological variations impact karst development only when structural features are present to provide secondary porosity that enhances chemical weathering. The distribution of karst features and the geologic factors governing their development and distribution should be taken into account when land-use decisions in karst terrains are made

Treatment of heavy metals by iron oxide coated and natural gravel media in Sustainable urban Drainage Systems.

Science.gov (United States)

Norris, M J; Pulford, I D; Haynes, H; Dorea, C C; Phoenix, V R

2013-01-01

Sustainable urban Drainage Systems (SuDS) filter drains are simple, low-cost systems utilized as a first defence to treat road runoff by employing biogeochemical processes to reduce pollutants. However, the mechanisms involved in pollution attenuation are poorly understood. This work aims to develop a better understanding of these mechanisms to facilitate improved SuDS design. Since heavy metals are a large fraction of pollution in road runoff, this study aimed to enhance heavy metal removal of filter drain gravel with an iron oxide mineral amendment to increase surface area for heavy metal scavenging. Experiments showed that amendment-coated and uncoated (control) gravel removed similar quantities of heavy metals. Moreover, when normalized to surface area, iron oxide coated gravels (IOCGs) showed poorer metal removal capacities than uncoated gravel. Inspection of the uncoated microgabbro gravel indicated that clay particulates on the surface (a natural product of weathering of this material) augmented heavy metal removal, generating metal sequestration capacities that were competitive compared with IOCGs. Furthermore, when the weathered surface was scrubbed and removed, metal removal capacities were reduced by 20%. When compared with other lithologies, adsorption of heavy metals by microgabbro was 10-70% higher, indicating that both the lithology of the gravel, and the presence of a weathered surface, considerably influence its ability to immobilize heavy metals. These results contradict previous assumptions which suggest that gravel lithology is not a significant factor in SuDS design. Based upon these results, weathered microgabbro is suggested to be an ideal lithology for use in SuDS.

Petrologic evolution of CM chondrites: The difficulty of discriminating between nebular and parent-body effects

Science.gov (United States)

Kerridge, J. F.; McSween, H. Y., Jr.; Bunch, T. E.

1994-07-01

We wish to draw attention to a major controversy that has arisen in the area of CM-chondrite petrology. The problem is important because its resolution will have profound implications for ideas concerning nebular dynamics, gas-solid interactions in the nebula, and accretionary processes in the nebula, among other issues. On the one hand, cogent arguments have been presented that 'accretionary dust mantles,' were formed in the solar nebula prior to accretion of the CM parent asteroid(s). On the other hand, no-less-powerful arguments have been advanced that a significant fraction of the CM lithology is secondary, produced by aqueous alteration in the near-surface regions of an asteroid-sized object. Because most, if not all, CM chondrites are breccias, these two views could coexist harmoniously, were it not for the fact that some of the coarse-grained lithologies surrounded by 'accretion dust mantles' are themselves of apparently secondary origin. Such an observation must clearly force a reassessment of one or both of the present schools of thought. Our objective here is to stimulate such a reassessment. Four possible resolutions of this conflict may be postulated. First, perhaps nature found a way of permitting such secondary alteration to take place in the nebula. Second, maybe dust mantles could form in a regolith, rather than a nebular, environment. Third, it is possible that dust mantles around secondary lithologies are different from those around primary lithologies. Finally, perhaps formation of CM chondrites involved a more complex sequence of events than visualized so far, so that some apparently 'primary' processes postdated certain 'secondary' processes.

Sorption-desorption studies on tuff III. A continuation of studies with samples from Jackass Flats and Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Wolfsberg, K.; Aguilar, R.D.; Bayhurst, B.P.

1981-05-01

This report is the third in a series of reports describing studies of sorption and migration of radionuclides in tuff. The investigations were extended to lithologies of tuff not previously studied. Continuing experiments with uranium, plutonium, and americium are described. The dependence of sorption on the concentration of the sorbing element and on the solution-to-solid ratio was investigated for a number of nuclides and two lithologies. A circulating system was designed for measuring sorption ratios. Values obtained from this system, batch measurements, and column elutions are compared. Progress on measuring and controlling Eh is described

Combined interpretation of SkyTEM and high-resolution seismic data

DEFF Research Database (Denmark)

Høyer, Anne-Sophie; Lykke-Andersen, Holger; Jørgensen, Flemming Voldum

2011-01-01

made based on AEM (SkyTEM) and high-resolution seismic data from an area covering 10 km2 in the western part of Denmark. As support for the interpretations, an exploration well was drilled to provide lithological and logging information in the form of resistivity and vertical seismic profiling. Based...... on the resistivity log, synthetic SkyTEM responses were calculated with a varying number of gate-times in order to illustrate the effect of the noise-level. At the exploration well geophysical data were compared to the lithological log; in general there is good agreement. The same tendency was recognised when Sky...

Effects of host rock stratigraphy on the formation of ring-faults and the initiation of collapse calderas

International Nuclear Information System (INIS)

Kinvig, H S; Geyer, A; Gottsmann, J

2008-01-01

Most collapse calderas can be attributed to subsidence of the magma chamber roof along bounding sub-vertical normal faults (ring-faults) after a decompression of the magma chamber, following eruption. Here, we present new numerical models that use a Finite Element Method to investigate the effects of variable crustal stratigraphy (lithology/thickness/order of strata) above a magma chamber, on local stress field distribution and how these in turn compare with existing criteria for ring-fault initiation. Results indicate that the occurrence and relative distribution of mechanically different lithologies may be influential in generating or inhibiting caldera collapse.

Types of ore-controlling zonations at uranium deposits in sedimentary rocks; their main features and methods for identification

International Nuclear Information System (INIS)

Maksimova, M.F.; Sergeev, I.P.; Strelyanov, N.P.; Shevchenko, O.E.

1985-01-01

Classes of uranium mineralization controlling zonations, singled out in agreement with lithogenesis stages, are considered. They are as follows: facial zonation zonation of geochemical facies of early diagenesis (monofacial lateral zonation, interfacial frontal and lateral zonations), epigenetic geochemical zonation, hypergenous geochemical zonation. The latter comprises complete oxidation zone, partial oxidation and cementation zone, non-oxidated rocks. When studying zonations the mineralogo-geochemical mapping is conducted, as a result of which a number of profiles is constructed: lithological, autogenetic mineralization propagation, epigenetic zonation. As a result of lithological, structural, hydrogeochemical and epigenetic profiling and mapping the map of uranium mineralization prediction is drawn up

Effects of host rock stratigraphy on the formation of ring-faults and the initiation of collapse calderas

Energy Technology Data Exchange (ETDEWEB)

Kinvig, H S; Geyer, A; Gottsmann, J [Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queen' s Road, BS8 1RJ, Bristol (United Kingdom)

2008-10-01

Most collapse calderas can be attributed to subsidence of the magma chamber roof along bounding sub-vertical normal faults (ring-faults) after a decompression of the magma chamber, following eruption. Here, we present new numerical models that use a Finite Element Method to investigate the effects of variable crustal stratigraphy (lithology/thickness/order of strata) above a magma chamber, on local stress field distribution and how these in turn compare with existing criteria for ring-fault initiation. Results indicate that the occurrence and relative distribution of mechanically different lithologies may be influential in generating or inhibiting caldera collapse.

Detection of Mg spinel lithologies on central peak of crater ...

Indian Academy of Sciences (India)

identified Fe bearing Mg-spinel-rich rock types are defined by their strong 2-μm ... The Modified Gaussian Modeling (MGM) analysis ... study the deep crustal and/or upper mantle composition and may lead to a fresh ... Lunar surface; Mg-spinel; central peak; Theophilus; remote sensing. .... The explanation of these spec-.

A field technique for rapid lithological discrimination and ore mineral ...

Indian Academy of Sciences (India)

This work illustrates the efficiency of field spectroscopy for rapid identification of minerals in ore body, alteration zone and host rocks. The adopted procedure involves collection of field spectra, their processing for noise, spectral matching and spectral un-mixing with selected library end-members. Average weighted spectral ...

Natural radioactivity of Loire river sediments: relations with the lithology

International Nuclear Information System (INIS)

Patryl, L.

2000-01-01

This study has been carried out on request of the Loire-Bretagne water agency by the Laboratory of geology of Tours univ. (EA2100 GeEAC) in collaboration with CEA-Le Ripault. The main objective was the study of the nature and distribution of natural radioactivity in the Loire river alluvial deposits, its origin in the rocks of the surrounding basins and its links with the alluvial petrography. The radioactive flux linked with the sediments of the bottom of the river has been also determined. The Loire river and its main affluents have been the object of radiological and petrographic analyses (grain size, sands and clays mineralogy, organic matter content). The average radioactivities of 40 K, 238 U and 228 Ac in the alluvial deposits are 934.3 ± 164.7 Bq.kg -1 , 50.6 ± 30.8 Bq.kg -1 and 28.8 ± 18.1 Bq.kg -1 , respectively. The average radioactivity of 238 U, 228 Ac and their daughter products is statistically higher in Loire superieure (Massif Central mounts) than in Loire moyenne (Paris basin). The activities of 238 U and 228 Ac are mainly influenced by the grain size of the alluvial deposits and by the mineralogical composition of the sand fraction. The alluvial deposits are mainly sandy and the coarse fraction is the most abundant. The primary radioactivity is carried by the few zircons of the sediments. The activity of the uranium and thorium families increase with the feldspars content. The fixation of radioactivity seems to be linked with the presence of clay minerals inside the weathered feldspar grains which are abundant in the sands. The radioactivity of the Loire river alluvial deposits shows no important changes with respect to the substratums because of a smoothing due to the predominance of longitudinal fluxes with respect to the lateral ones. The impact of an old uranium mine on the alluvial deposits of the Besbre river is detectable along about a tenth of km s downstream only. Because of the strong variations of radioactivity with granularity, a grain-size standardized method of expression of radioactivity is proposed. (J.S.)

Continents as lithological icebergs: The importance of buoyant lithospheric roots

Science.gov (United States)

Abbott, D.H.; Drury, R.; Mooney, W.D.

1997-01-01

An understanding of the formation of new continental crust provides an important guide to locating the oldest terrestrial rocks and minerals. We evaluated the crustal thicknesses of the thinnest stable continental crust and of an unsubductable oceanic plateau and used the resulting data to estimate the amount of mantle melting which produces permanent continental crust. The lithospheric mantle is sufficiently depleted to produce permanent buoyancy (i.e., the crust is unsubductable) at crustal thicknesses greater than 25-27 km. These unsubductable oceanic plateaus and hotspot island chains are important sources of new continental crust. The newest continental crust (e.g., the Ontong Java plateau) has a basaltic composition, not a granitic one. The observed structure and geochemistry of continents are the result of convergent margin magmatism and metamorphism which modify the nascent basaltic crust into a lowermost basaltic layer overlain by a more silicic upper crust. The definition of a continent should imply only that the lithosphere is unsubductable over ??? 0.25 Ga time periods. Therefore, the search for the oldest crustal rocks should include rocks from lower to mid-crustal levels.

Lithological control on phytolith carbon sequestration in moso bamboo forests.

Science.gov (United States)

Li, Beilei; Song, Zhaoliang; Wang, Hailong; Li, Zimin; Jiang, Peikun; Zhou, Guomo

2014-06-11

Phytolith-occluded carbon (PhytOC) is a stable carbon (C) fraction that has effects on long-term global C balance. Here, we report the phytolith and PhytOC accumulation in moso bamboo leaves developed on four types of parent materials. The results show that PhytOC content of moso bamboo varies with parent material in the order of granodiorite (2.0 g kg(-1)) > granite (1.6 g kg(-1)) > basalt (1.3 g kg(-1)) > shale (0.7 g kg(-1)). PhytOC production flux of moso bamboo on four types of parent materials varies significantly from 1.0 to 64.8 kg CO₂ ha(-1) yr(-1), thus a net 4.7 × 10(6) -310.8 × 10(6) kg CO₂ yr(-1) would be sequestered by moso bamboo phytoliths in China. The phytolith C sequestration rate in moso bamboo of China will continue to increase in the following decades due to nationwide bamboo afforestation/reforestation, demonstrating the potential of bamboo in regulating terrestrial C balance. Management practices such as afforestation of bamboo in granodiorite area and granodiorite powder amendment may further enhance phytolith C sequestration through bamboo plants.

Characteristics of lithology and tectonic setting in the Korean peninsula

International Nuclear Information System (INIS)

Lee, Byungjoo; Chae, Byunggon; Choi, Junghae

2011-01-01

The west coast of the Korean Peninsula is bounded by the Korean Bay to the north and the Yellow Sea to the south; the east coast is bounded by the East Sea. Two hundred kilometers separate the peninsula from eastern China. The Japanese islands of Honshu and Kyushu are located 206 kilometers to the southeast, just across the Korea Strait. Because of its unique geographical location, Chinese culture filtered into Japan through Korea; a common cultural sphere of Buddhism and Confucianism was thus established between the three countries. The total area of the peninsula, including the islands, is 222,154 square kilometers of which about 45 percent, excluding the area in the Demilitarized Zone, constitutes the territory of South Korea. There are about 3,000 islands belonging to Korea. The islands are located mostly around the Yellow Sea; Ulleungdo, the largest island in the East Sea, serves as a major fishery base as does Dokdo island. Important islands within South Korea territory include Jejudo, the largest island, which lies off the southwest corner of the peninsula, Geojedo, Ganghwado, and Namhaedo. Nearly 70 percent of the Korean Peninsula is covered by mountains and hills. Located mostly in the southern and the western regions, these hills give way gradually to increasingly higher mountains toward the eastern and the northern end. On the whole, the western and southern slopes of the peninsula are wide with some plains and basins along rivers, while the eastern slope is very narrow because the high mountains hug the East Sea coastline

Characteristics of lithology and tectonic setting in the Korean peninsula

Energy Technology Data Exchange (ETDEWEB)

Lee, Byungjoo; Chae, Byunggon; Choi, Junghae [KIGAM, Daejeon (Korea, Republic of)

2011-07-01

The west coast of the Korean Peninsula is bounded by the Korean Bay to the north and the Yellow Sea to the south; the east coast is bounded by the East Sea. Two hundred kilometers separate the peninsula from eastern China. The Japanese islands of Honshu and Kyushu are located 206 kilometers to the southeast, just across the Korea Strait. Because of its unique geographical location, Chinese culture filtered into Japan through Korea; a common cultural sphere of Buddhism and Confucianism was thus established between the three countries. The total area of the peninsula, including the islands, is 222,154 square kilometers of which about 45 percent, excluding the area in the Demilitarized Zone, constitutes the territory of South Korea. There are about 3,000 islands belonging to Korea. The islands are located mostly around the Yellow Sea; Ulleungdo, the largest island in the East Sea, serves as a major fishery base as does Dokdo island. Important islands within South Korea territory include Jejudo, the largest island, which lies off the southwest corner of the peninsula, Geojedo, Ganghwado, and Namhaedo. Nearly 70 percent of the Korean Peninsula is covered by mountains and hills. Located mostly in the southern and the western regions, these hills give way gradually to increasingly higher mountains toward the eastern and the northern end. On the whole, the western and southern slopes of the peninsula are wide with some plains and basins along rivers, while the eastern slope is very narrow because the high mountains hug the East Sea coastline.

A field technique for rapid lithological discrimination and ore mineral ...

Indian Academy of Sciences (India)

weighted spectral similarity and effective peak matching techniques were used to draw end-members from library. ...... D A 2006 A mobile tram system for systematic sampling .... Rogers A D and Christensen P R 2007 Surface mineralogy of.

Applying machine learning to global surface ocean and seabed data to reveal the controls on the distribution of deep-sea sediments

Science.gov (United States)

Dutkiewicz, Adriana; Müller, Dietmar; O'Callaghan, Simon

2017-04-01

World's ocean basins contain a rich and nearly continuous record of environmental fluctuations preserved as different types of deep-sea sediments. The sediments represent the largest carbon sink on Earth and its largest geological deposit. Knowing the controls on the distribution of these sediments is essential for understanding the history of ocean-climate dynamics, including changes in sea-level and ocean circulation, as well as biological perturbations. Indeed, the bulk of deep-sea sediments comprises the remains of planktonic organisms that originate in the photic zone of the global ocean implying a strong connection between the seafloor and the sea surface. Machine-learning techniques are perfectly suited to unravelling these controls as they are able to handle large sets of spatial data and they often outperform traditional spatial analysis approaches. Using a support vector machine algorithm we recently created the first digital map of seafloor lithologies (Dutkiewicz et al., 2015) based on 14,400 surface samples. This map reveals significant deviations in distribution of deep-sea lithologies from hitherto hand-drawn maps based on far fewer data points. It also allows us to explore quantitatively, for the first time, the relationship between oceanographic parameters at the sea surface and lithologies on the seafloor. We subsequently coupled this global point sample dataset of 14,400 seafloor lithologies to bathymetry and oceanographic grids (sea-surface temperature, salinity, dissolved oxygen and dissolved inorganic nutrients) and applied a probabilistic Gaussian process classifier in an exhaustive combinatorial fashion (Dutkiewicz et al., 2016). We focused on five major lithologies (calcareous sediment, diatom ooze, radiolarian ooze, clay and lithogenous sediment) and used a computationally intensive five-fold cross-validation, withholding 20% of the data at each iteration, to assess the predictive performance of the machine learning method. We find that

Application of airborne gamma spectrometric survey data to estimating terrestrial gamma-ray dose rates: An example in California

International Nuclear Information System (INIS)

Wollenberg, H.A.; Revzan, K.L.; Smith, A.R.

1992-01-01

The authors examine the applicability of radioelement data from the National Aerial Radiometric Reconnaissance (NARR) to estimate terrestrial gamma-ray absorbed dose rates, by comparing dose rates calculated from aeroradiometric surveys of U, Th, and K concentrations in 1 x 2 degree quadrangles with dose rates calculated from a radiogeologic data base and the distribution of lithologies in California. Gamma-ray dose rates increase generally from north to south following lithological trends. Low values of 25--30 nG/h occur in the northernmost quadrangles where low-radioactivity basaltic and ultramafic rocks predominate. Dose rates then increase southward due to the preponderance of clastic sediments and basic volcanics of the Franciscan Formation and Sierran metamorphics in north central and central California, and to increasing exposure southward of the Sierra Nevada batholith, Tertiary marine sedimentary rocks, intermediate to acidic volcanics, and granitic rocks of the Coast Ranges. High values, to 100 nGy/h occur in southeastern California, due primarily to the presence of high-radioactivity Precambrian and pre Cenozoic metamorphic rocks. Lithologic-based estimates of mean dose rates in the quadrangles generally match those from aeroradiometric data, with statewide means of 63 and 60 nGy/h, respectively. These are intermediate between a population-weighted global average of 51 nGy/h and a weighted continental average of 70 nGy/h, based on the global distribution of rock types. The concurrence of lithologically- and aeroradiometrically- determined dose rates in California, with its varied geology and topography encompassing settings representative of the continents, indicates that the NARR data are applicable to estimates of terrestrial absorbed dose rates from natural gamma emitters

Predicting multi-scale relationships between geomorphology and bedrock geology of the rocky intertidal in Central and Northern California

Science.gov (United States)

Wheeler, A.; Aiello, I. W.

2014-12-01

Substratum geology is fundamental in shaping rocky shore morphology. Specific lithologies have various responses to wave action, tectonic features (e.g. fractures, faults) and sedimentary structures (e.g. bedding), creating distinctive weathering profiles. Along with local oceanography and climate forcing, different rock substrata create coastal morphologies that can vary distinctly between scales, ranging from mm to km. Despite the complexity of the system, qualitative observations show coastal areas with similar rock types share similar geomorphologies. Thus, a statistic relationship between geomorphology (expressed for instance by surface parameter rugosity) and geology can be envisaged. There are multiple benefits of finding such a relationship, as rocky intertidal geomorphology can be an important determinant in which organisms can settle, grow, and survive in near shore communities: allowing the prediction of geomorphologic parameters determining coastal ecology solely based on substratum geology, a crucial aspect in guiding the selection of marine protected areas. This study presents preliminary results of multi-scale geospatial surveys (cm to tens of meters) of rocky intertidal outcrops from Central to Northern California using a Terrestrial Laser Scanner. The outcrops investigated are representative of the most common igneous and sedimentary rocks in California (granitoids, conglomerates, sandstones, mudstones) and metamorphic units. The statistical analysis of the survey data support the hypothesis that surface properties can change significantly with changing scale, each rock type having distinct surface characteristics which are similar to comparable lithologies exposed at different locations. These scale dependent variations are controlled by different lithologic and structural characteristics of the outcrop in question. Our data also suggests lithologic variability within a rock unit could be a very significant factor in controlling changes in

Heterogeneous slip and rupture models of the San Andreas fault zone based upon three-dimensional earthquake tomography

Energy Technology Data Exchange (ETDEWEB)

Foxall, William [Univ. of California, Berkeley, CA (United States)

1992-11-01

Crystal fault zones exhibit spatially heterogeneous slip behavior at all scales, slip being partitioned between stable frictional sliding, or fault creep, and unstable earthquake rupture. An understanding the mechanisms underlying slip segmentation is fundamental to research into fault dynamics and the physics of earthquake generation. This thesis investigates the influence that large-scale along-strike heterogeneity in fault zone lithology has on slip segmentation. Large-scale transitions from the stable block sliding of the Central 4D Creeping Section of the San Andreas, fault to the locked 1906 and 1857 earthquake segments takes place along the Loma Prieta and Parkfield sections of the fault, respectively, the transitions being accomplished in part by the generation of earthquakes in the magnitude range 6 (Parkfield) to 7 (Loma Prieta). Information on sub-surface lithology interpreted from the Loma Prieta and Parkfield three-dimensional crustal velocity models computed by Michelini (1991) is integrated with information on slip behavior provided by the distributions of earthquakes located using, the three-dimensional models and by surface creep data to study the relationships between large-scale lithological heterogeneity and slip segmentation along these two sections of the fault zone.

Application of ASTER SWIR bands in mapping anomaly pixels for Antarctic geological mapping

International Nuclear Information System (INIS)

Beiranvand Pour, Amin; Hashim, Mazlan; Park, Yongcheol

2017-01-01

Independent component analysis (ICA) was applied to shortwave infrared (SWIR) bands of ASTER satellite data for detailed mapping of alteration mineral zones in the context of polar environments, where little prior information is available. The Oscar II coast area north-eastern Graham Land, Antarctic Peninsula (AP) was selected to conduct a remote sensing satellite-based mapping approach to detect alteration mineral assemblages. Anomaly pixels in the ICA image maps related to spectral features of Al-O-H, Fe, Mg-O-H and CO3 groups were detected using SWIR datasets of ASTER. ICA method provided image maps of alteration mineral assemblages and discriminate lithological units with little available geological data for poorly mapped regions and/or without prior geological information for unmapped regions in northern and southern sectors of Oscar II coast area, Graham Land. The results of this investigation demonstrated the applicability of ASTER spectral data for lithological and alteration mineral mapping in poorly exposed lithologies and inaccessible regions, particularly using the image processing algorithm that are capable to detect anomaly pixels targets in the remotely sensed images, where no prior information is available. (paper)

Exploration of Uranium in Simpang Kanan, East Aceh, Preliminary Prospecting Stages

International Nuclear Information System (INIS)

Djalil, A; Sutriyono, A; Sajiyo

1998-01-01

Exploration of uranium in simpang kanan, east aceh, preliminary prospecting stages. The research has been carried out to obtain the knowledge of geology, radiometry and geochemistry in relation with U prospect development. Based on the similarity of lithology in takengon sector which indicates the existence of uranium mineralization. Research method consist of geological observation, radiometric measurements of outcrops, boulders and stream sediment and heavy mineral samples. Laboratory analysis consist of petrography, autoradiography and uranium content analysis of stream sediment and rock samples. The lithology consist of slate, quartzite, marble, granite, dacite, limestone, carbonaceous sandstone, black claystone, sandstone, siltstone, carbonaceous siltstone. This area found, has been folded with the folding axis direction of NW-SE. Fault structures are generally formed as strike slip fault and several location as normal fault and heavy minerals anomalous was interpreted from granite and sandstone- siltstone. Occurrences of the geochemical anomaly, lithology and geological structures, there has been shown that few location is being the prospect area covered about 70 km of 1800km prospecting area, so it is suggested that in those related prospect area should be performed further observation

Petrologic comparisons of Cayley and Descartes on the basis of Apollo 16 soils from stations 4 and 11

Science.gov (United States)

Basu, A.; Mckay, D. S.

1984-01-01

Petrologic aspects of the Cayley and Descartes formations are reviewed in the light of new data on Apollo 16 soils. Specific comparison of the modal abundances of lithic fragments in drive tube sample 64001/2 from the slopes of Stone Mountain (station 4) and in soil 67941 from the North Ray Crater rim (station 11) shows that melt rocks, especially poikilitic rocks, are more abundant at station 4 than at station 11; the reverse is true for fragmental breccias. Such lithologic differences suggest that stations 4 and 11 do not belong to the same geologic formation. Metamorphosed breccias are pervasive in both the formations and may represent a local component that has been reworked and diluted as fresh materials were added. Lithologic compositions inferred from the study of soil samples are different from lithologic compositions inferred from the study of rake samples or breccia clasts. This difference may be related to a mixing of material of different grain size distributions. The petrology of soils at the Apollo 16 site may not accurately reflect original material associated with either the Descartes or the Cayley formation because of extensive mixing with local material.

Study on geologic structure of hydrogenic deposits

International Nuclear Information System (INIS)

1985-01-01

The problem of studying geologic structure of hydrogenic uranium deposits developed by underground leaching (UL), is elucidated. Geologic maps of the surface are used to characterize engineering and geologic conditions. Main geologoic papers are maps drawn up according to boring data. For total geologic characteristic of the deposit 3 types of maps are usually drawn up: structural maps of isohypses or isodepths, lithologic-facies maps on the horizon and rhythm, and maps of epigenetic alterations (geochemmcal). Besides maps systems of sections are drawn up. Problems of studying lithologic-facies and geohemical peculiarities of deposits, epigenotic alterations, substance composition of ores and enclosing rocks, documentation and core sampting, are considered in details

Predicting the occurrence of mixed mode failure associated with hydraulic fracturing, part 2 water saturated tests

Energy Technology Data Exchange (ETDEWEB)

Bauer, Stephen J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Broome, Scott Thomas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Choens, Charles [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Barrow, Perry Carl [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-09-14

Seven water-saturated triaxial extension experiments were conducted on four sedimentary rocks. This experimental condition was hypothesized more representative of that existing for downhole hydrofracture and thus it may improve our understanding of the phenomena. In all tests the pore pressure was 10 MPa and confirming pressure was adjusted to achieve tensile and transitional failure mode conditions. Using previous work in this LDRD for comparison, the law of effective stress is demonstrated in extension using this sample geometry. In three of the four lithologies, no apparent chemo-mechanical effect of water is apparent, and in the fourth lithology test results indicate some chemo-mechanical effect of water.

The snake geothermal drilling project. Innovative approaches to geothermal exploration

Energy Technology Data Exchange (ETDEWEB)

Shervais, John W. [Utah State Univ., Logan, UT (United States); Evans, James P. [Utah State Univ., Logan, UT (United States); Liberty, Lee M. [Boise State Univ., ID (United States); Schmitt, Douglas R. [University of Alberta, Canada; Blackwell, David D. [Southern Methodist Univ., Dallas, TX (United States)

2014-02-21

The goal of our project was to test innovative technologies using existing and new data, and to ground-truth these technologies using slim-hole core technology. The slim-hole core allowed us to understand subsurface stratigraphy and alteration in detail, and to correlate lithologies observed in core with surface based geophysical studies. Compiled data included geologic maps, volcanic vent distribution, structural maps, existing well logs and temperature gradient logs, groundwater temperatures, and geophysical surveys (resistivity, magnetics, gravity). New data included high-resolution gravity and magnetic surveys, high-resolution seismic surveys, three slimhole test wells, borehole wireline logs, lithology logs, water chemistry, alteration mineralogy, fracture distribution, and new thermal gradient measurements.

Method of Creation of “Core-Gisseismic Attributes” Dependences With Use of Trainable Neural Networks

Directory of Open Access Journals (Sweden)

Gafurov Denis

2016-01-01

Full Text Available The study describes methodological techniques and results of geophysical well logging and seismic data interpretation by means of trainable neural networks. Objects of research are wells and seismic materials of Talakan field. The article also presents forecast of construction and reservoir properties of Osa horizon. The paper gives an example of creation of geological (lithological -facial model of the field based on developed methodical techniques of complex interpretation of geologicgeophysical data by trainable neural network. The constructed lithological -facial model allows specifying a geological structure of the field. The developed methodical techniques and the trained neural networks may be applied to adjacent sites for research of carbonate horizons.

Climatic fluctuations and origin of sediments during Alleroed in Latvia

International Nuclear Information System (INIS)

Stelle, V.

2000-01-01

The Alleroed sediments are known from more than 30 sites in Latvia, but usually each of them reflects incomplete part of this important interval within the Late-Glacial. The lithological and palinological record of stratigraphically complete sections (Lielauce a.o.) proves that Alleroed is not climatically homogeneous. Relative cooling had been observed in middle part (about 11500-11300 years ago) of this interval. The pollen and spore composition, the radiocarbon dates and the changes in lithology of sediments during Alleroed time are discussed. The entire Alleroed interval may be subdivided into three stratigraphic units: lower (AL-1), middle (AL-2) and upper (AL-3). (author)

First-order shallow aquifer characteristics across Europe: The International Hydrogeological Map of Europe at scale 1:1.5 Million (IHME1500)

Science.gov (United States)

Günther, Andreas; Duscher, Klaus; Broda, Stefan; Clos, Patrick; Reichling, Jörg

2017-04-01

Since the mid of the last century, pan-European hydrogeological overview-mapping is conducted at the scale 1 : 1.5 Million following common standards and guidelines to interpret suitable geologic mapping units in terms of potential uppermost aquifer (or non-aquifer) characteristics. These comprises potential aquifer productivities and general hydrogeological aquifer conditions (fissured vs. porous). The printed IHME1500 dataset successively elaborated and published from 1970 - 2013 consists of 25 individual map sheets. Besides the potential aquifer characterization grouped in six classes, IHME1500 offers a complete coverage of lithological material properties of potential shallow aquifer assemblages, and tracelines of major fault structures. Regional information on groundwater surfaces, aquifer thicknesses and depths, locations and characteristics of groundwater springs and other punctual information related to European groundwater resources is present for some areas in selected map sheets, however not digitally available. Synoptic IHME1500 vector data consists of a topographically corrected, seamless and harmonized polygon layer with attribute information on potential aquifer productivity and lithology. While the standardized aquifer-classification is relatively easy to harmonize across the entire mapped area, the lithological information of IHME1500 is presented using sheet-specific legend information resulting in more than 1000 aquifer lithology classes. An attempt was made to harmonize this information utilizing a specifically developed taxonomic scheme, treating consolidated, partly consolidated and unconsolidated materials separately. The translation of the original lithological information into this scheme allows for a hierarchical grouping of the mapping units into five generalization levels, where the highest aggregation level displays a ternary map showing the distribution of consolidated, partially consolidated and unconsolidated aquifer materials. The

Local regularity analysis of strata heterogeneities from sonic logs

Directory of Open Access Journals (Sweden)

S. Gaci

2010-09-01

Full Text Available Borehole logs provide geological information about the rocks crossed by the wells. Several properties of rocks can be interpreted in terms of lithology, type and quantity of the fluid filling the pores and fractures.

Here, the logs are assumed to be nonhomogeneous Brownian motions (nhBms which are generalized fractional Brownian motions (fBms indexed by depth-dependent Hurst parameters H(z. Three techniques, the local wavelet approach (LWA, the average-local wavelet approach (ALWA, and Peltier Algorithm (PA, are suggested to estimate the Hurst functions (or the regularity profiles from the logs.

First, two synthetic sonic logs with different parameters, shaped by the successive random additions (SRA algorithm, are used to demonstrate the potential of the proposed methods. The obtained Hurst functions are close to the theoretical Hurst functions. Besides, the transitions between the modeled layers are marked by Hurst values discontinuities. It is also shown that PA leads to the best Hurst value estimations.

Second, we investigate the multifractional property of sonic logs data recorded at two scientific deep boreholes: the pilot hole VB and the ultra deep main hole HB, drilled for the German Continental Deep Drilling Program (KTB. All the regularity profiles independently obtained for the logs provide a clear correlation with lithology, and from each regularity profile, we derive a similar segmentation in terms of lithological units. The lithological discontinuities (strata' bounds and faults contacts are located at the local extrema of the Hurst functions. Moreover, the regularity profiles are compared with the KTB estimated porosity logs, showing a significant relation between the local extrema of the Hurst functions and the fluid-filled fractures. The Hurst function may then constitute a tool to characterize underground heterogeneities.

Integrating non-colocated well and geophysical data to capture subsurface heterogeneity at an aquifer recharge and recovery site

Science.gov (United States)

Gottschalk, Ian P.; Hermans, Thomas; Knight, Rosemary; Caers, Jef; Cameron, David A.; Regnery, Julia; McCray, John E.

2017-12-01

Geophysical data have proven to be very useful for lithological characterization. However, quantitatively integrating the information gained from acquiring geophysical data generally requires colocated lithological and geophysical data for constructing a rock-physics relationship. In this contribution, the issue of integrating noncolocated geophysical and lithological data is addressed, and the results are applied to simulate groundwater flow in a heterogeneous aquifer in the Prairie Waters Project North Campus aquifer recharge site, Colorado. Two methods of constructing a rock-physics transform between electrical resistivity tomography (ERT) data and lithology measurements are assessed. In the first approach, a maximum likelihood estimation (MLE) is used to fit a bimodal lognormal distribution to horizontal crosssections of the ERT resistivity histogram. In the second approach, a spatial bootstrap is applied to approximate the rock-physics relationship. The rock-physics transforms provide soft data for multiple point statistics (MPS) simulations. Subsurface models are used to run groundwater flow and tracer test simulations. Each model's uncalibrated, predicted breakthrough time is evaluated based on its agreement with measured subsurface travel time values from infiltration basins to selected groundwater recovery wells. We find that incorporating geophysical information into uncalibrated flow models reduces the difference with observed values, as compared to flow models without geophysical information incorporated. The integration of geophysical data also narrows the variance of predicted tracer breakthrough times substantially. Accuracy is highest and variance is lowest in breakthrough predictions generated by the MLE-based rock-physics transform. Calibrating the ensemble of geophysically constrained models would help produce a suite of realistic flow models for predictive purposes at the site. We find that the success of breakthrough predictions is highly

Drainage feature about coalbed methane wells in different hydrogeological conditions in Fanzhuaug area

Institute of Scientific and Technical Information of China (English)

NI Xiao-ming; LIN Ran; WANG Yan-bin

2012-01-01

It is aa important guarantee to enhance the production of coalbed methane (CBM) and reduce the project investment by finding out the drainage feature about CBM wells in different hydrogeological conditions.Based on the CBM exploration and development data on the Fanzhuang block in southeast Qinshui Basin and combined with the seepage principle and lithology on the roof and the bottom coalbed,the mathematical model of integrated permeability was established.By permeability experiments of the different lithologies on the roof and the floor within the 20 m range combined with the log curves,the integrated permeability of different lithological combinations were obtained.The starting pressure gradient and permeability of the roof and the floor for different lithologies was tested by "differential pressure-flow method".The relationships between the starting pressure gradient and the integrated permeability were obtained.The critical distance of limestone water penetrating into coal reservoirs was calculated.According to the drainage feature of CBM wells combined with the drainage data of some CBM wells,the results show that,when limestone water can penetrate into coal reservoirs,the daily water production is high and the daily gas production is low although there is no gas at the beginning of the drainage process,the CBM wells stop discharging water within 6 months after the gas began to come out,and the gas production is steadily improved.When limestone water can not penetrate into coal reservoirs,the daily water production is low and the daily gas production is high at the beginning of the drainage process,and it almost stops discharging water after some time when the gas come out,the daily gas production increases,and the cumulative water production is much lower.

Core fracture analysis applied to ground water flow systems: Chickamauga Group, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Bittner, E.; Dreier, R.B.

1989-01-01

The objective of this study is to correlate hydrologic properties with detailed geologic fabrics and to investigate the influence of a complex geologic setting on ground water systems. The Chickamauga Group (CH) located in Bethel Valley on the DOE Oak Ridge Reservation is comprised of limestones and interbedded shales. Five core holes (CH 1-5), oriented across strike, provide a cross section of the CH and were mapped for fracture density, orientation and cross-cutting relationships as well as lithologic variations. Correlation of structural and lithologic features with downhole geophysical logs and hydraulic conductivity values shows a relationship between lithology, fracture density and increased permeability in an otherwise low-permeability environment. Structures identified as influential in enhancing hydraulic conductivity include contractional bedding plane and tectonic stylolites and extensional fractures. Three sets of extensional fractures are indicated by cross-cutting relationships and various degrees of veining. Hydraulic conductivity values (K) for the five wells indicate two ground water flow systems in the valley. A shallow system (up to 150 feet deep) shows a range in K from 10E-4 centimeters per second to 10E-6 centimeters per second. Shallow horizons show more open fractures than are observed at depth, and these fractures appear to control the enhanced K in the shallow system. A subhorizontal interface that is not defined by pre-existing structures or a stratigraphic horizon separates the two flow systems. The deeper system ranges in K values from 10E-9 centimeters per second to 10E-5 centimeters per second. The higher K values at depth correspond to increased fracture density at lithologic contacts, zones of tectonic stylolitization and partially veined extension fractures. 11 refs., 11 figs., 2 tabs

Mechanical and physical properties of hydrothermally altered rocks, Taupo Volcanic Zone, New Zealand

Science.gov (United States)

Wyering, L. D.; Villeneuve, M. C.; Wallis, I. C.; Siratovich, P. A.; Kennedy, B. M.; Gravley, D. M.; Cant, J. L.

2014-11-01

Mechanical characterization of hydrothermally altered rocks from geothermal reservoirs will lead to an improved understanding of rock mechanics in a geothermal environment. To characterize rock properties of the selected formations, we prepared samples from intact core for non-destructive (porosity, density and ultrasonic wave velocities) and destructive laboratory testing (uniaxial compressive strength). We characterised the hydrothermal alteration assemblage using optical mineralogy and existing petrography reports and showed that lithologies had a spread of secondary mineralisation that occurred across the smectite, argillic and propylitic alteration zones. The results from the three geothermal fields show a wide variety of physical rock properties. The testing results for the non-destructive testing shows that samples that originated from the shallow and low temperature section of the geothermal field had higher porosity (15 - 56%), lower density (1222 - 2114 kg/m3) and slower ultrasonic waves (1925 - 3512 m/s (vp) and 818 - 1980 m/s (vs)), than the samples from a deeper and higher temperature section of the field (1.5 - 20%, 2072 - 2837 kg/m3, 2639 - 4593 m/s (vp) and 1476 - 2752 m/s (vs), respectively). The shallow lithologies had uniaxial compressive strengths of 2 - 75 MPa, and the deep lithologies had strengths of 16 - 211 MPa. Typically samples of the same lithologies that originate from multiple wells across a field have variable rock properties because of the different alteration zones from which each sample originates. However, in addition to the alteration zones, the primary rock properties and burial depth of the samples also have an impact on the physical and mechanical properties of the rock. Where this data spread exists, we have been able to derive trends for this specific dataset and subsequently have gained an improved understanding of how hydrothermal alteration affects physical and mechanical properties.

Using stable isotopes to estimate and compare mean residence times in contrasting geologic catchments (Attert River, NW Luxembourg)

Science.gov (United States)

Martínez-Carreras, N.; Fenicia, F.; Frentress, J.; Wrede, S.; Pfister, L.

2012-04-01

In recent years, stable isotopes have been increasingly used to characterize important aspects of catchment hydrological functioning, such as water storage dynamics, flow pathways and water sources. These characteristics are often synthesized by the Mean Residence Time (MRT), which is a simple catchment descriptor that employ the relation of distinct stable isotopic signatures in the rainfall input and streamflow output of a catchment that are significantly dampened through sub-surface propagation. In this preliminary study, MRT was estimated in the Attert River catchment (NW Luxembourg), where previous studies have shown that lithology exerts a major control on runoff generation. The Attert catchment lies at the transition zone of contrasting bedrock lithology: the Northern part is characterized by Devonian schist of the Ardennes massif, while sedimentary deposits of sandstone and marls dominate in the south of the catchment. As a consequence of differing lithologic characteristics, hydrological processes change across scales. The schistose catchments exhibit a delayed shallow groundwater component, sandstone catchments have slow-responding year-round groundwater component, whereas flashy runoff regimes prevails in the marly catchments. Under these circumstances, the MRTs are expected to vary significantly according to lithology, and provide additional understanding in internal catchment processes and their scale dependencies. In order to test this, bi-weekly monitoring of rainfall and discharge stable water isotope composition (oxygen-18 and deuterium) has been carried out since 2007 in 10 nested sub-catchments ranging in size from 0.4 to 247 km2 in the Attert catchment. MRT was estimated using different lumped convolution integral models and sine wave functions with varying transit times distributions (TTDs). TTDs were evaluated through calibration. Further research efforts will deal with the application of conceptual models to simulate and compare TTD, using

Characteristics of volcanic reservoirs and distribution rules of effective reservoirs in the Changling fault depression, Songliao Basin

Directory of Open Access Journals (Sweden)

Pujun Wang

2015-11-01

Full Text Available In the Songliao Basin, volcanic oil and gas reservoirs are important exploration domains. Based on drilling, logging, and 3D seismic (1495 km2 data, 546 sets of measured physical properties and gas testing productivity of 66 wells in the Changling fault depression, Songliao Basin, eruptive cycles and sub-lithofacies were distinguished after lithologic correction of the 19,384 m volcanic well intervals, so that a quantitative analysis was conducted on the relation between the eruptive cycles, lithologies and lithofacies and the distribution of effective reservoirs. After the relationship was established between lithologies, lithofacies & cycles and reservoir physical properties & oil and gas bearing situations, an analysis was conducted on the characteristics of volcanic reservoirs and the distribution rules of effective reservoirs. It is indicated that 10 eruptive cycles of 3 sections are totally developed in this area, and the effective reservoirs are mainly distributed at the top cycles of eruptive sequences, with those of the 1st and 3rd Members of Yingcheng Formation presenting the best reservoir properties. In this area, there are mainly 11 types of volcanic rocks, among which rhyolite, rhyolitic tuff, rhyolitic tuffo lava and rhyolitic volcanic breccia are the dominant lithologies of effective reservoirs. In the target area are mainly developed 4 volcanic lithofacies (11 sub-lithofacies, among which upper sub-lithofacies of effusive facies and thermal clastic sub-lithofacies of explosion lithofacies are predominant in effective reservoirs. There is an obvious corresponding relationship between the physical properties of volcanic reservoirs and the development degree of effective reservoirs. The distribution of effective reservoirs is controlled by reservoir physical properties, and the formation of effective reservoirs is influenced more by porosity than by permeability. It is concluded that deep volcanic gas exploration presents a good

Drainage development and incision rates in an Upper Pleistocene Basalt-Limestone Boundary Channel: The Sa'ar Stream, Golan Heights, Israel

Science.gov (United States)

Shtober-Zisu, N.; Inbar, M.; Mor, D.; Jicha, B. R.; Singer, B. S.

2018-02-01

Long-term fluvial incision processes and corresponding geomorphic evolution are difficult to quantify, especially in complex systems affected by lithological and tectonic factors. Volcanic landscapes offer the most appropriate environment for the study of landscape evolution, as there is a clear starting time of formation and the lithology is homogenous. In the present study we aim to: (1) analyse the interplay of construction and incision processes throughout eruptive activity; (2) study fluvial erosion processes; (3) analyse sedimentary and volcanic lithological responses to channel erosion; and (4) calculate the incision rates in young basaltic bedrock. We have integrated existing and new 40Ar/39Ar ages of lava flows with estimates of channel geometry and tectonic activity, and considered process geomorphology concepts, to fully understand evolution of a bedrock channel incised at the boundary between basalts and sedimentary rocks with coeval active volcanic processes forcing drainage evolution. Our findings indicate that the Sa'ar basin evolution is controlled by: (1) rock strength of the mixed lithology; (2) alternating cycles of volcanic activity followed by erosion and incision; and (3) the Plio-Pleistocene uplift of Mt. Hermon. The carbonate slopes composing the southern flank of Mt. Hermon are moderate (18-26%) while the basalt slopes deriving from the Golan Heights are much steeper (26-51%). The highly erodible sedimentary rocks at Mt. Hermon's piedmont accelerated river incision, shaping a 650 m wide by 100 m deep canyon. Inside the canyon, the steep channel slope (8.6%) enables downstream movement of large boulders, including autochthonous mega-blocks (D90 size > 2.5 m); 24 knickpoints were identified using DS plots, developed within a knick zone over a distance of 6 km. The brittle and porous structure of the rubbly and blocky interflow layers (clinkers), interbedded between two massive basalt flows, enhances erosion and accelerates scouring of the

Fluid prediction using rock modelling and reconnaissance. AVO analysis - A case study from the North Sea

Energy Technology Data Exchange (ETDEWEB)

Osdal, Bard; Granli, John Reidar

1998-12-31

Seismic lithology and fluid phase prediction (LFP) is becoming an important part of seismic interpretation, and can contribute significantly to risk reduction prior to drilling. In this presentation there is focused on quantitative interpretation of the amplitudes in a 2-D dataset, with respect to presence of hydrocarbons. Different aspect of the working producer, like data quality (well data and seismic data), rock modelling and seismic modelling will be illustrated. In the present study only one well has been used for calibration and to investigate the seismic response for different fluid and lithology scenarios. The rock modelling included evaluation of seismic parameter effect for different fluid and porosities. 1 ref., 4 figs.

Research on sequence stratigraphy of Shuixigou group, jurassic in Yili basin

International Nuclear Information System (INIS)

Li Shengfu; Wang Guo; Wei Anxin; Qi Junrang; Zhang Zhongwang

2006-01-01

The Shuixigou Group, Jurassic in Yili basin is a set of coal-bearing clastic formation formed under basically consistent tectonic stress and sedimentary environment. In the middle of the Group (Sangonghe Formation) abrupt changes appear in the lithology and the colour of rocks, and an abrupt turning in logging curve appears correspondingly. Using the point view of sequence stratigraphy, the authors analyse the above phenomenon in aspects of the chrono-stratigraphy, the lithology, the sedimentary system tract, the sedimentary rhythum, as well as the interpretation of logging curves, and suggest that a unconformity surface (or a sequence boundary) exists in the middle of the Group, and try make a re-division of sequence stratigraphy for the Shuixigou Group. (authors)

A geological survey of the Lac du Bonnet batholith, Manitoba

International Nuclear Information System (INIS)

McCrank, G.F.D.

1985-02-01

This report presents the results of a geological survey of the Lac du Bonnet batholith in Manitoba. The survey consisted of field mapping of the lithologies and the joint systems throughout the batholith, and the examination of lineaments identified on aerial photographs and Landsat imagery. Petrographic descriptions and a map of the lithologies, an analysis of the fracture systems and a lineament map are presented. The results of various regional geophysical surveys were used as an aid to the interpretation of the batholith's contacts and in the interpretation of lineaments as possible faults. A comparison of the Lac du Bonnet Batholith with the Eye-Dashwa Lakes Pluton near Atikokan, Ontario is also presented

Factors affecting finite strain estimation in low-grade, low-strain clastic rocks

Science.gov (United States)

Pastor-Galán, Daniel; Gutiérrez-Alonso, Gabriel; Meere, Patrick A.; Mulchrone, Kieran F.

2009-12-01

The computer strain analysis methods SAPE, MRL and DTNNM have permitted the characterization of finite strain in two different regions with contrasting geodynamic scenarios; (1) the Talas Ala Tau (Tien Shan, Kyrgyzs Republic) and (2) the Somiedo Nappe and Narcea Antiform (Cantabrian to West Asturian-Leonese Zone boundary, Variscan Belt, NW of Iberia). The performed analyses have revealed low-strain values and the regional strain trend in both studied areas. This study also investigates the relationship between lithology (grain size and percentage of matrix) and strain estimates the two methodologies used. The results show that these methods are comparable and the absence of significant finite strain lithological control in rocks deformed under low metamorphic and low-strain conditions.

Three dimensional visualization in support of Yucca Mountain Site characterization activities

International Nuclear Information System (INIS)

Brickey, D.W.

1992-01-01

An understanding of the geologic and hydrologic environment for the proposed high-level nuclear waste repository at Yucca Mountain, NV is a critical component of site characterization activities. Conventional methods allow visualization of geologic data in only two or two and a half dimensions. Recent advances in computer workstation hardware and software now make it possible to create interactive three dimensional visualizations. Visualization software has been used to create preliminary two-, two-and-a-half-, and three-dimensional visualizations of Yucca Mountain structure and stratigraphy. The three dimensional models can also display lithologically dependent or independent parametric data. Yucca Mountain site characterization studies that will be supported by this capability include structural, lithologic, and hydrologic modeling, and repository design

Cordilleran metamorphic core complexes and their uranium favorability

International Nuclear Information System (INIS)

Coney, P.J.; Reynolds, S.J.

1980-11-01

The objective of this report is to provide a descriptive body of knowledge on Cordilleran metamorphic core complexes including their lithologic and structural characteristics, their distribution within the Cordillera, and their evolutionary history and tectonic setting. The occurrence of uranium in the context of possibility for uranium concentration is also examined. This volume contains appendices of the following: annotated bibliography of Cordilleran metamorphic core complexes; annotated bibliography of the uranium favorability of Cordilleran metamorphic core complexes; uranium occurrences in the Cordilleran metamorphic core complex belt; and geology, uranium favorability, uranium occurrences and tectonic maps of individual Cordilleran metamorphic core complexes; and locations, lithologic descriptions, petrographic information and analytical data for geochemical samples

A preliminary study on the regional fracture systems for deep geological disposal of high level radioactive waste in Korea

Energy Technology Data Exchange (ETDEWEB)

Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Koh, Young Kown; Park, Byoung Yoon [Korea Atomic Energy Research Institute, Taejeon (Korea)

2000-03-01

For the deep geological disposal of high-level radioactive waste, it is essential to characterize the fracture system in rock mass which has a potential pathways of nuclide. Currently, none of research results are in classification and detailed properties for the fracture system in Korea. This study aims to classify and describe the regional fracture system in lithological and geotectonical point of view using literature review, shaded relief map, and aeromagnetic survey data. This report contains the following: - Theoretical review of the fracture development mechanism. - Overall fault and fracture map. - Geological description on the distributional characteristics of faults and fractures(zone) in terms of lithological domain and tectonical province. 122 refs., 22 figs., 4 tabs. (Author)

Geohydrologic-engineering geology evaluation of the Selma Group in western Alabama and northeast Mississippi for possible radioactive waste disposal

International Nuclear Information System (INIS)

Gonzales, S.

1975-06-01

The following topics are discussed: regional stratigraphy, lithologic characteristic-chalk sequences, structural geology settting, earthquakes and historical seismicity, regional geomorphology, recovery of geological resources, and groundwater hydrology

Waste Isolation Pilot Plant Salado hydrology program data report number 3

International Nuclear Information System (INIS)

Chace, D.A.; Roberts, R.M.; Palmer, J.B.; Kloska, M.B.; Fort, M.D.; Martin, G.J.; Stensrud, W.A.

1998-01-01

WIPP Salado Hydrology Program Data Report number-sign 3 presents hydrologic data collected during permeability testing, coupled permeability and hydrofracture testing, and gas-threshold-pressure testing of the Salado Formation performed from November 1991 through October 1995. Fluid-pressure monitoring data representing August 1989 through May 1995 are also included. The report presents data from the drilling and testing of three boreholes associated with the permeability testing program, nine boreholes associated with the coupled permeability and hydrofracture testing program, and three boreholes associated with the gas-threshold-pressure testing program. The purpose of the permeability testing program was to provide data with which to interpret the disturbed and undisturbed permeability and pore pressure characteristics of the different Salado Formation lithologies. The purpose of the coupled permeability and hydrofracture testing program was to provide data with which to characterize the occurrence, propagation, and direction of pressure induced fractures in the Salado Formation lithologies, especially MB139. The purpose of the gas-threshold-pressure testing program was to provide data with which to characterize the conditions under which pressurized gas displaces fluid in the brine-saturated Salado Formation lithologies. All of the holes were drilled from the WIPP underground facility 655 m below ground surface in the Salado Formation

Alteration mineral mapping in inaccessible regions using target detection algorithms to ASTER data

International Nuclear Information System (INIS)

Pour, A B; Hashim, M; Park, Y

2017-01-01

In this study, the applications of target detection algorithms such as Constrained Energy Minimization (CEM), Orthogonal Subspace Projection (OSP) and Adaptive Coherence Estimator (ACE) to shortwave infrared bands of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data was investigated to extract geological information for alteration mineral mapping in poorly exposed lithologies in inaccessible domains. The Oscar II coast area north-eastern Graham Land, Antarctic Peninsula (AP) was selected in this study to conduct a satellite-based remote sensing mapping technique. It is an inaccessible region due to the remoteness of many rock exposures and the necessity to travel over sever mountainous and glacier-cover terrains for geological field mapping and sample collection. Fractional abundance of alteration minerals such as muscovite, kaolinite, illite, montmorillonite, epidote, chlorite and biotite were identified in alteration zones using CEM, OSP and ACE algorithms in poorly mapped and unmapped zones at district scale for the Oscar II coast area. The results of this investigation demonstrated the applicability of ASTER shortwave infrared spectral data for lithological and alteration mineral mapping in poorly exposed lithologies and inaccessible regions, particularly using the image processing algorithms that are capable to detect sub-pixel targets in the remotely sensed images, where no prior information is available. (paper)

Anciet marble quarries in Lesvos island Greece

Science.gov (United States)

Mataragkas, M.; Mataragkas, D.

2009-04-01

ANCIENT MARBLE QUARRIES IN LESBOS ISLAND, GREECE Varti- Matarangas M.1 & Matarangas D. 1 Institute of Geological and Mining Exploration (IGME), Olympic Village, Entrance C, ACHARNAE 13677, GREECE myrsini@igme.gr , myrsini@otenet.g r A B S T R A C T Ten ancient marble quarries of Lesbos Island, most of them previously unknown, have been studied, in the frame of the research study on the ancient marble quarries in the Aegean Sea. In the present paper the geological, petrological and morphological features of the aforementioned quarries are examined. Concerning the six ancient quarries located in the areas of Tarti, Agia Paraskevi (Tsaf), Mageiras, Loutra, Latomi (Plomari) and Thermi, the authochthonous neopaleozoic unit constitutes their geological formation, while their hosting lithological formations are the included crystalline limestone lens like beds. In two ancient quarries in the areas Moria and Alyfanta, the geological formation is the authochthonous upper Triassic series and the hosting lithological formation the upper Triassic carbonate sequence, while in the areas of Akrasi-Abeliko and Karyni, the geological formation is the thrust Triassic unit and the lithological hosting formations are the included strongly deformed or not crystalline limestone lenticular beds. Furthermore, the petrographic features were also determined permitting the identification of the building stones that have been used.

Waste Isolation Pilot Plant Salado hydrology program data report {number_sign}3

Energy Technology Data Exchange (ETDEWEB)

Chace, D.A.; Roberts, R.M.; Palmer, J.B.; Kloska, M.B.; Fort, M.D.; Martin, G.J.; Stensrud, W.A. [INTERA, Inc., Albuquerque, NM (United States)

1998-01-01

WIPP Salado Hydrology Program Data Report {number_sign}3 presents hydrologic data collected during permeability testing, coupled permeability and hydrofracture testing, and gas-threshold-pressure testing of the Salado Formation performed from November 1991 through October 1995. Fluid-pressure monitoring data representing August 1989 through May 1995 are also included. The report presents data from the drilling and testing of three boreholes associated with the permeability testing program, nine boreholes associated with the coupled permeability and hydrofracture testing program, and three boreholes associated with the gas-threshold-pressure testing program. The purpose of the permeability testing program was to provide data with which to interpret the disturbed and undisturbed permeability and pore pressure characteristics of the different Salado Formation lithologies. The purpose of the coupled permeability and hydrofracture testing program was to provide data with which to characterize the occurrence, propagation, and direction of pressure induced fractures in the Salado Formation lithologies, especially MB139. The purpose of the gas-threshold-pressure testing program was to provide data with which to characterize the conditions under which pressurized gas displaces fluid in the brine-saturated Salado Formation lithologies. All of the holes were drilled from the WIPP underground facility 655 m below ground surface in the Salado Formation.

Petrology of the Indian Eucrite Piplia Kalan

Science.gov (United States)

Buchanan, Paul C.; Mittlefehldt, D. W.; Hutchinson, R.; Koeberl, C.; Lindstrom, D. J.; Pandit, M. K.

1999-01-01

Piplia Kalan is an equilibrated eucrite consisting of 60-80 vol.% lithic clasts in a subordinate brecciated matrix. Ophitic/subophitic lithic clasts fall into two groups: finer-grained lithology A and coarser-grained lithology B. Very fine-grained clasts (lithology C) also occur and originally were hypocrystalline in texture. The variety of materials represented in Piplia Kalan suggests cooling histories ranging from quenching or fast crystallization to slower crystallization. Despite textural differences, clasts and matrix have similar mineral and bulk compositions. Thus. Piplia Kalan is probably best classified as a genomict breccia that could represent fragments of a single lava flow or shallow intrusive body, including fine-grained or glassy outer margin and more slowly cooled coarser-grained interior. Piplia Kalan displays evidence of an early shock event, including brecciated matrix and areas of lithic clasts that contain fine-grained, equigranular pyroxene between deformed feldspar laths. The meteorite also displays evidence of at least one episode of thermal metamorphism: hypocrystalline materials are recrystallized to hornfelsic textures and the matrix has a nonporous texture similar to those of eucrites that were affected by post-brecciation heating. Veins of brown glass transect both lithic clasts and brecciated matrix and indicate a second, post-metamorphism shock event.

Geologic report of the Maquoketa Shale, New Albany Shale, and Borden Group rocks in the Illinois Basin as potential solid waste repository sites

International Nuclear Information System (INIS)

Droste, J.B.; Vitaliano, C.J.

1976-06-01

We have evaluated the Illinois Basin in order to select a ''target site'' for a possible solid nuclear waste repository. In the process we have been mindful of geology (particularly stratigraphy and lithology and structure), terrane, population density, land use, land ownership and accessibility. After taking these restrictions into account, we have singled out a strip of land in south central Indiana in which we have selected four potential sites worthy of further exploration. In three of the sites the geology, lithology, and depth below the surface are more than adequate for crypt purposes in two separate formations--the Maquoketa Shale of the Ordovician System and the New Albany Shale-Borden Group of the Upper Devonian-Mississippian Systems. The interval between the two is several hundred feet. The geology and associated features in the fourth site are undoubtedly similar to those in the first three. In all four selections a sizeable proportion of the land is in public ownership and the population density in the nonpublicly owned land is low. The geology, lithology, and position of the target formations have been projected into the sites in question from data provided by drill core records of the Indiana Geological Survey. Precise details would, of course, require exploratory drilling on the selected site

Soil moisture in relation to geologic structure and lithology, northern California

Science.gov (United States)

Rich, E. I. (Principal Investigator)

1980-01-01

The author has identified the following significant results. Structural features in the Norther California Coast Ranges are clearly discernable on Nite-IR images and some of the structural linears may results in an extension of known faults within the region. The Late Mesozoic marine sedimentary rocks along the western margin of the Sacramento Valley are clearly defined on the Nite-IR images and in a gross way individual layers of sandstone can be differentiated from shale. Late Pleistocene alluvial fans are clearly differentiated from second generation Holocene fans on the basis of tonal characteristics. Although the tonal characteristics change with the seasons, the differentiation of the two sets of fans is still possible.

Mg-spinel lithology: A new rock type on the lunar farside

Science.gov (United States)

Pieters, C.M.; Besse, S.; Boardman, J.; Buratti, B.; Cheek, L.; Clark, R.N.; Combe, J.-P.; Dhingra, D.; Goswami, J.N.; Green, R.O.; Head, J.W.; Isaacson, P.; Klima, R.; Kramer, G.; Lundeen, S.; Malaret, E.; McCord, T.; Mustard, J.; Nettles, J.; Petro, N.; Runyon, C.; Staid, M.; Sunshine, J.; Taylor, L.A.; Thaisen, K.; Tompkins, S.; Whitten, J.

2011-01-01

High-resolution compositional data from Moon Mineralogy Mapper (M 3) for the Moscoviense region on the lunar farside reveal three unusual, but distinctive, rock types along the inner basin ring. These are designated "OOS" since they are dominated by high concentrations of orthopyroxene, olivine, and Mg-rich spinel, respectively. The OOS occur as small areas, each a few kilometers in size, that are widely separated within the highly feldspathic setting of the basin rim. Although the abundance of plagioclase is not well constrained within the OOS, the mafic mineral content is exceptionally high, and two of the rock types could approach pyroxenite and harzburgite in composition. The third is a new rock type identified on the Moon that is dominated by Mg-rich spinel with no other mafic minerals detectable (lunar crust; they may thus be near contemporaneous with crustal products from the cooling magma ocean. Copyright ?? 2011 by the American Geophysical Union.

Quantifying sediment sources in a lowland agricultural catchment pond using {sup 137}Cs activities and radiogenic {sup 87}Sr/{sup 86}Sr ratios

Energy Technology Data Exchange (ETDEWEB)

Le Gall, Marion; Evrard, Olivier [Laboratoire des Sciences et de l' Environnement, UMR 8212 (CEA/CNRS/UVSQ), Université Paris-Saclay, Domaine du CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex (France); Foucher, Anthony [E.A 6293, Laboratoire GéoHydrosystèmes Continentaux (GéHCO), Université F. Rabelais de Tours, Faculté des Sciences et Techniques, Parc de Grandmont, 37200 Tours (France); Laceby, J. Patrick [Laboratoire des Sciences et de l' Environnement, UMR 8212 (CEA/CNRS/UVSQ), Université Paris-Saclay, Domaine du CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex (France); Salvador-Blanes, Sébastien [E.A 6293, Laboratoire GéoHydrosystèmes Continentaux (GéHCO), Université F. Rabelais de Tours, Faculté des Sciences et Techniques, Parc de Grandmont, 37200 Tours (France); Thil, François; Dapoigny, Arnaud; Lefèvre, Irène [Laboratoire des Sciences et de l' Environnement, UMR 8212 (CEA/CNRS/UVSQ), Université Paris-Saclay, Domaine du CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex (France); Cerdan, Olivier [Département Risques et Prévention, Bureau de Recherches Géologiques et Minières, 3 avenue Claude Guillemin, 45060 Orléans (France); and others

2016-10-01

Soil erosion often supplies high sediment loads to rivers, degrading water quality and contributing to the siltation of reservoirs and lowland river channels. These impacts are exacerbated in agricultural catchments where modifications in land management and agricultural practices were shown to accelerate sediment supply. In this study, sediment sources were identified with a novel tracing approach combining cesium ({sup 137}Cs) and strontium isotopes ({sup 87}Sr/{sup 86}Sr) in the Louroux pond, at the outlet of a lowland cultivated catchment (24 km{sup 2}, Loire River basin, France) representative of drained agricultural areas of Northwestern Europe. Surface soil (n = 36) and subsurface channel bank (n = 17) samples were collected to characterize potential sources. Deposited sediment (n = 41) was sampled across the entire surface of the pond to examine spatial variation in sediment deposits. In addition, a 1.10 m sediment core was sampled in the middle of the pond to reconstruct source variations throughout time. {sup 137}Cs was used to discriminate between surface and subsurface sources, whereas {sup 87}Sr/{sup 86}Sr ratios discriminated between lithological sources. A distribution modeling approach quantified the relative contribution of these sources to the sampled sediment. Results indicate that surface sources contributed to the majority of pond (μ 82%, σ 1%) and core (μ 88%, σ 2%) sediment with elevated subsurface contributions modeled near specific sites close to the banks of the Louroux pond. Contributions of the lithological sources were well mixed in surface sediment across the pond (i.e., carbonate sediment contribution, μ 48%, σ 1% and non-carbonate sediment contribution, μ 52%, σ 3%) although there were significant variations of these source contributions modeled for the sediment core between 1955 and 2013. These fluctuations reflect both the progressive implementation of land consolidation schemes in the catchment and the eutrophication of

Aquifer Characterization and Groundwater Potential Assessment

African Journals Online (AJOL)

Timothy Ademakinwa

Keywords: Aquifer Characterization, Groundwater Potential, Electrical Resistivity, Lithologic Logs ... State Water Corporation currently cannot meet the daily water ... METHOD OF STUDY ... sections which were constrained with the available.

The bedrock electrical conductivity structure of Northern Ireland

Science.gov (United States)

Beamish, David

2013-08-01

An airborne geophysical survey of the whole of Northern Ireland has provided over 4.8 M estimates of the bedrock conductivity over the wide range of geological formations present. This study investigates how such data can be used to provide additional knowledge in relation to existing digital geological map information. A by-product of the analysis is a simplification of the spatially aggregated information obtained in such surveys. The methodology used is a GIS-based attribution of the conductivity estimates using a lithological classification of the bedrock formations. A 1:250k geological classification of the data is performed leading to a 56 unit lithological and geostatistical analysis of the conductivity information. The central moments (medians) of the classified data are used to provide a new digital bedrock conductivity map of Northern Ireland with values ranging from 0.32 to 41.36 mS m-1. This baseline map of conductivities displays a strong correspondence with an existing 4 quadrant, chrono-geological description of Northern Ireland. Once defined, the baseline conductivity map allows departures from the norm to be assessed across each specific lithological unit. Bulk electrical conductivity is controlled by a number of petrophysical parameters and it is their variation that is assessed by the procedures employed. The igneous rocks are found to display the largest variability in conductivity values and many of the statistical distributions are multi-modal. A sequence of low-value modes in these data are associated with intrusives within volcanic complexes. These and much older Neoproterzoic rocks appear to represent very low porosity formations that may be the product of rapid cooling during emplacement. By way of contrast, extensive flood basalts (the Antrim lavas) record a well-defined and much higher median value (12.24 mS m-1) although they display complex spatial behaviour in detail. Sedimentary rocks appear to follow the broad behaviours anticipated

Recommended procedures and techniques for the petrographic description of bituminous coals

Science.gov (United States)

Chao, E.C.T.; Minkin, J.A.; Thompson, C.L.

1982-01-01

Modern coal petrology requires rapid and precise description of great numbers of coal core or bench samples in order to acquire the information required to understand and predict vertical and lateral variation of coal quality for correlation with coal-bed thickness, depositional environment, suitability for technological uses, etc. Procedures for coal description vary in accordance with the objectives of the description. To achieve our aim of acquiring the maximum amount of quantitative information within the shortest period of time, we have adopted a combined megascopic-microscopic procedure. Megascopic analysis is used to identify the distinctive lithologies present, and microscopic analysis is required only to describe representative examples of the mixed lithologies observed. This procedure greatly decreases the number of microscopic analyses needed for adequate description of a sample. For quantitative megascopic description of coal microlithotypes, microlithotype assemblages, and lithotypes, we use (V) for vitrite or vitrain, (E) for liptite, (I) for inertite or fusain, (M) for mineral layers or lenses other than iron sulfide, (S) for iron sulfide, and (X1), (X2), etc. for mixed lithologies. Microscopic description is expressed in terms of V representing the vitrinite maceral group, E the exinite group, I the inertinite group, and M mineral components. volume percentages are expressed as subscripts. Thus (V)20(V80E10I5M5)80 indicates a lithotype or assemblage of microlithotypes consisting of 20 vol. % vitrite and 80% of a mixed lithology having a modal maceral composition V80E10I5M5. This bulk composition can alternatively be recalculated and described as V84E8I4M4. To generate these quantitative data rapidly and accurately, we utilize an automated image analysis system (AIAS). Plots of VEIM data on easily constructed ternary diagrams provide readily comprehended illustrations of the range of modal composition of the lithologic units making up a given coal

Quality of water from crystalline rock aquifers in New England, New Jersey, and New York, 1995-2007

Science.gov (United States)

Flanagan, Sarah M.; Ayotte, Joseph D.; Robinson, Gilpin R.

2012-06-25

Crystalline bedrock aquifers in New England and parts of New Jersey and New York (NECR aquifers) are a major source of drinking water. Because the quality of water in these aquifers is highly variable, the U.S. Geological Survey (USGS) statistically analyzed chemical data on samples of untreated groundwater collected from 117 domestic bedrock wells in New England, New York, and New Jersey, and from 4,775 public-supply bedrock wells in New England to characterize the quality of the groundwater. The domestic-well data were from samples collected by the USGS National Water-Quality Assessment (NAWQA) Program from 1995 through 2007. The public-supply-well data were from samples collected for the U.S. Environmental Protection Agency (USEPA) Safe Drinking Water Act (SDWA) Program from 1997 through 2007. Chemical data compiled from the domestic wells include pH, specific conductance, dissolved oxygen, alkalinity, and turbidity; 6 nitrogen and phosphorus compounds, 14 major ions, 23 trace elements, 222radon gas (radon), 48 pesticide compounds, and 82 volatile organic compounds (VOCs). Additional samples were collected from the domestic wells for the analysis of gross alpha- and gross beta-particle radioactivity, radium isotopes, chlorofluorocarbon isotopes, and the dissolved gases methane, carbon dioxide, nitrogen, and argon. Chemical data compiled from the public-supply wells include pH, specific conductance, nitrate, iron, manganese, sodium, chloride, fluoride, arsenic, uranium, radon, combined radium (226radium plus 228radium), gross alpha-particle radioactivity, and methyl tert-butyl ether (MtBE).Patterns in fluoride, arsenic, uranium, and radon distributions were discernable when the data were compared to lithology groupings of the bedrock, indicating that the type of bedrock has an effect on the quality of groundwater from NECR aquifers. Fluoride concentrations were significantly higher in groundwater samples from the alkali granite, peraluminous granite, and

Characterization of Rocks and Grouts to Support DNA's Verification Program

National Research Council Canada - National Science Library

Martin, J

2000-01-01

.... Specifically, test data was generated for use with DNA's HYDROPLUS program. The tests performed included unconfined compression tests, uniaxial strain tests, physical properties, ultrasonic velocities, XRD mineralogy, and lithologic descriptions...

19th Scientific Readings Devoted to P.N. Chirvinskiy

Directory of Open Access Journals (Sweden)

I. Ya. Ilaltdinov

2017-03-01

Full Text Available Scientific conference devoted to P.N. Chirvinskiy was held in the Perm State University (January 2017. The problems of mineralogy, petrology, lithology, metallogeny and geochemistry were discussed.

The relationship between depositional system and ore-formation of sandstone-type uranium deposits in Dongsheng area, Ordos basin

International Nuclear Information System (INIS)

Zhao Honggang; Ou Guangxi

2006-01-01

The analysis on depositional system plays a very important role in studying sandstone-type uranium deposits. Based on depositional system analysis and sequence stratigraphy, and through the study of depositional system characteristics and the spatial distribution of sedimentary facies, the evolution of sedimentary environments as well as the sequence stratigraphy of Zhiluo Formation in Dongsheng area, Ordos basin, authors have come to the following conclusions, (1) the spatial distribution of sand bodies is controlled by the planar distribution of sedimentary facies, which, in turn, affects the spatial distribution of ore-hosting sand bodies; (2) the evolution of sedimentary facies and sedimentary environments creates good lithofacies and lithological conditions favorable for interlayer oxidation; (3) the spatial lithologic combination of 'three layer structure' is controlled by sedimentary sequence. (authors)

Model structural uncertainty quantification and hydrologic parameter and prediction error analysis using airborne electromagnetic data

DEFF Research Database (Denmark)

Minsley, B. J.; Christensen, Nikolaj Kruse; Christensen, Steen

Model structure, or the spatial arrangement of subsurface lithological units, is fundamental to the hydrological behavior of Earth systems. Knowledge of geological model structure is critically important in order to make informed hydrological predictions and management decisions. Model structure...... is never perfectly known, however, and incorrect assumptions can be a significant source of error when making model predictions. We describe a systematic approach for quantifying model structural uncertainty that is based on the integration of sparse borehole observations and large-scale airborne...... electromagnetic (AEM) data. Our estimates of model structural uncertainty follow a Bayesian framework that accounts for both the uncertainties in geophysical parameter estimates given AEM data, and the uncertainties in the relationship between lithology and geophysical parameters. Using geostatistical sequential...

Cretaceous rocks of the Western Interior basin

International Nuclear Information System (INIS)

Molenaar, C.M.; Rice, D.D.

1988-01-01

The Cretaceous rocks of the conterminous United States are discussed in this chapter. Depositional facies and lithology are reviewed along with economic resources. The economic resources include coal, hydrocarbons, and uranium

GIS and SBF for estimating groundwater recharge of a mountainous ...

Indian Academy of Sciences (India)

was used to integrate five contributing factors: lithology, land cover/land use, lineaments, drainage, and slope. ... cultural regions, where groundwater consumption ..... network helps assess the characteristics of a ..... The development ...

A comparative study on the landslide susceptibility mapping using ...

Indian Academy of Sciences (India)

from faults, lithology, normalized difference vegetation index (NDVI), sediment transport index (STI), stream power ... economic losses and creating high maintenance costs, are ..... evidence method to landslide susceptibility map- ping using ...

Contribution to the knowledge of the Val le Chico Uruguay formation

International Nuclear Information System (INIS)

Pirelli, H.

1999-01-01

This research has been designed to contribute with Val le Chico Uruguay formation knowledge, taking into the alkaline type tectonic environment, geochronology, granitoid types, lithologies and mineralizations existing in the area

Well-Construction, Water-Level, and Water-Quality Data for Ground-Water Monitoring Wells for the J4 Hydrogeologic Study, Arnold Air Force Base, Tennessee

National Research Council Canada - National Science Library

Haugh, Connor J

1996-01-01

...) in Coffee County, Tennessee. The wells ranged from 28 to 289 feet deep and were installed to provide information on subsurface lithology, aquifer characteristics, ground-water levels, and ground-water quality...

Murgabskaya Oblast, a promising gas region of Central Asia

Energy Technology Data Exchange (ETDEWEB)

Amanniyazov, K.N.; Abdyyev, A.A.

1981-01-01

Gas fields of the Murgabskiy region are multiple-bed. The industrial gas content is associated with the sandy-terrigenous formations of the Shatlyk productive level of the lower Goterivskiy stage. The gas formation is anticlinal, occasionally floating. A map is compiled for the dispersal of the Shatlyk level which isolates the lithological composition, thickness, zones of dispersal of sandstone, etc. A description is provided for the map plan of the Shatlyk level. Alternation of sandy-argillaceous and carbonate rocks created favorable prerequisites for the development in the deposits of the Neocomian of lithological-physical pairs of ''collectors-mantles'', the basis for trap formation in structures and zones of lithological substitution. Within the Murgabskiy region, the greatest outlook for discovering new gas fields is confined to the Shatlyk level. It is associated with the central part of the Murgabskiy Basin where major deposits have already been discovered. A group of structures in the eastern submersion of the Kopetdag trough at the junction of the Murgabskiy Basin is important. The structures at the junction of East Kopetdag and the Murgabskiy Basin may be promising. The outlook for possible gas is associated with deposits of the lower cretaceous and Sharaplinksiy level. The main task must be comprehensive in investigation of the suprasaline apt-Neocomian and Kimmeridgian-Tithonian deposits as possible multiple-bed gas and oil containing masses.

Soil Structure Evaluation Across Geologic Transition Zones Using 2D Electrical Resistivity Imaging Technique

Directory of Open Access Journals (Sweden)

Geraldine C Anukwu

2017-06-01

Full Text Available This study utilizes the electrical resistivity values obtained using 2-D Electrical resistivity imaging (ERI technique to evaluate the subsurface lithology across different geological units. The primary objective was to determine the effect of subsurface lithology on the integrity of a road pavement, which had developed cracks and potholes at various locations. The dipole-dipole configuration was utilized and a total of nine traverses were established in the study area, whose geology cuts across both the basement and sedimentary complexes. The inverted resistivity section obtained showed significant variation in resistivity along established traverses and also across the different rock units, with the resistivity value ranging from about 4 ohm-m to greater than 7000 ohm- m. The lithology as interpreted from the resistivity section revealed the presence topsoil, clay, sandy clay, sand, sand stones/basement rocks, with varying vertical and horizontal arrangements to a depth of 40m. Results suggest that the geologic sequence and structure might have contributed to the observed pavement failure. The capability of the 2D ERI as an imaging tool is observed, especially across the transition zones as depicted in this study. The study further stressed the ability of this technique if properly designed and implemented, to be capable of providing a wealth of information that could complement other traditional geotechnical and geologic techniques.

Geophysical well logging operations and log analysis in Geothermal Well Desert Peak No. B-23-1

Energy Technology Data Exchange (ETDEWEB)

Sethi, D.K.; Fertl, W.H.

1980-03-01

Geothermal Well Desert Peak No. B-23-1 was logged by Dresser Atlas during April/May 1979 to a total depth of 2939 m (9642 ft). A temperature of 209/sup 0/C (408/sup 0/F) was observed on the maximum thermometer run with one of the logging tools. Borehole tools rated to a maximum temperature of 204.4/sup 0/C (400/sup 0/F) were utilized for logging except for the Densilog tool, which was from the other set of borehole instruments, rated to a still higher temperature, i.e., 260/sup 0/C (500/sup 0/F). The quality of the logs recorded and the environmental effects on the log response have been considered. The log response in the unusual lithologies of igneous and metamorphic formations encountered in this well could be correlated with the drill cutting data. An empirical, statistical log interpretation approach has made it possible to obtain meaningful information on the rocks penetrated. Various crossplots/histograms of the corrected log data have been generated on the computer. These are found to provide good resolution between the lithological units in the rock sequence. The crossplotting techniques and the statistical approach were combined with the drill cutting descriptions in order to arrive at the lithological characteristics. The results of log analysis and recommendations for logging of future wells have been included.

Advances in complex reservoir evaluation based on geophysical well logs

Energy Technology Data Exchange (ETDEWEB)

Fertl, W.H.; Sinha, A.K. (Western Atlas International, Inc., Houston, TX (USA)); McDougall, J.G. (Western Atlas Canada Ltd., Calgary, AB (Canada))

1988-09-01

The matrix of reservoirs having complex lithologies, cause different density, neutron, and acoustic responses. Therefore the lithologies and effective porosity of reservoirs can be determined by using various crossplot techniques on data collected from two of these logs. The Complex Reservoir Analysis program (CRA) computes lithology, porosity, water saturation and relative permeabilities in formations with interbedded limestone, dolomite, and anhydrite. Porosity options include crossplot and individual log response techniques. Corrections for light hydrocarbons were applied. In solving for porosity and mineral volumes, sand, limestone, dolomite, and anhydrite lines were defined on either density/neutron or neutron/acoustic crossplots. Four additional mineral lines were specified. Incorporation of Pe data from the Z-Densilog provided a significant advance in evaluating complex reservoirs via the Z-CRA analysis. The classic reservoir evaluation program CLASS, was used to perform both minerals and shaly evaluation based on density, neutron, resistivity, and natural gamma ray spectral measurements. Computations included total and effective porosities, fluid saturation distribution based on the Wasman-Smits model, productivity indices, and volume and distribution of clay minerals. Additional computed formation parameters included log-derived cation exchange capacity and hydrogen index of dry clay matrix to determine the type and amount of smectite, illite and chlorite/kaolinite present. Canadian field experiences was used to illustrate and support the techniques described. 11 refs., 11 figs., 6 tabs.

Estimation of hydraulic permeability considering the micro morphology of rocks of the borehole YAXCOPOIL-1 (Impact crater Chicxulub, Mexico)

Science.gov (United States)

Mayr, S. I.; Burkhardt, H.; Popov, Yu.; Wittmann, A.

2008-04-01

Internal surface, formation factor, Nuclear Magnetic Resonance (NMR)-T2 relaxation times and pore radius distributions were measured on representative core samples for the estimation of hydraulic permeability. Permeability is estimated using various versions of the classic Kozeny-Carman-equation (K-C) and a further development of K-C, the fractal PaRiS-model, taking into account the internal surface. In addition to grain and pore size distribution, directly connected to permeability, internal surface reflects the internal structure (“micro morphology”). Lithologies could be grouped with respect to differences in internal surface. Most melt rich impact breccia lithologies exhibit large internal surfaces, while Tertiary post-impact sediments and Cretaceous lithologies in displaced megablocks display smaller internal surfaces. Investigations with scanning electron microscopy confirm the correlation between internal surface and micro morphology. In addition to different versions of K-C, estimations by means of NMR, pore radius distributions and some gas permeability measurements serve for cross-checking and calibration. In general, the different estimations from the independent methods and the measurements are in satisfactory accordance. For Tertiary limestones and Suevites bulk with very high porosities (up to 35%) permeabilites between 10-14 and 10-16 m2 are found, whereas in lower Suevite, Cretaceous anhydrites and dolomites, bulk permeabilites are between 10-15 and 10-23 m2.

Vertical electrical sounding to delineate the potential aquifer zones ...

Indian Academy of Sciences (India)

Joy Choudhury

2017-09-06

fed irrigation, etc. The ... position is important for optimum groundwater ... regional scale to estimate natural groundwater ... lithology with depth by means of measured resis- .... stratification for all the VES survey carried out in.

The discovery and geophysical response of the Atlántida Cu-Au porphyry deposit, Chile

Science.gov (United States)

Hope, Matthew; Andersson, Steve

2016-03-01

The discovery of the Atlántida Cu-Au-Mo porphyry deposit, which is unconformably overlain by 25-80 m of gravels, is a recent example of exploration success under cover in a traditional mining jurisdiction. Early acquisition of geophysics was a key tool in the discovery, and in later guiding further exploration drilling throughout the life of the project. Detailed review of the geophysical response of the deposit, with respect to the distribution of lithologies and alteration, coupled with their petrophysical properties has allowed full characterisation, despite no exposure at the surface of host rock nor porphyry-style mineralisation. Data acquired over the project include induced polarisation, magnetotellurics, ground and airborne magnetics, ground-based gravimetry, and petrophysical sampling. The distribution of the key geological features of the deposit has been inferred via acquisition of petrophysical properties and interpretation of surface geophysical datasets. Magnetic susceptibility is influenced strongly by both alteration and primary lithology, whilst density variations are dominated by primary lithological control. Several studies have shown that electrical properties may map the footprint of the hydrothermal system and associated mineralisation, via a combination of chargeability and resistivity. These properties are observed in geophysical datasets acquired at surface and allow further targeting and sterilisation at the deposit and project scale. By understanding these geophysical characteristics in a geological context, these data can be used to infer distribution of lithological units, depth to exploration targets and the potential for high grade mineralisation. Future exploration will likely be increasingly reliant on the understanding of the surface manifestations of buried deposits in remotely acquired data. This review summarises the application and results of these principles at the Atlántida project of northern Chile. Geophysical data can be

Transformation of Serpentinite to Listvenite as Recorded in the Vein History of Rocks From Oman Drilling Project Hole BT1B

Science.gov (United States)

Manning, C. E.; Kelemen, P. B.; Michibayashi, K.; Harris, M.; Urai, J. L.; de Obeso, J. C.; Jesus, A. P. M.; Zeko, D.

2017-12-01

Oman Drilling Project Hole BT1B intersected 191 m of listvenite (magnesite + quartz rock) and serpentinite in the hanging wall of the basal thrust of the Oman ophiolite. Recovery was 100%. Listvenite is the dominant lithology in the upper plate rocks (166 m). Its shows wide color and textural variation, including pseudomorphic replacement of serpentinized peridotite. Serpentinite was encountered in two main contiguous intervals totaling 25 m. In light of the strongly metasomatic nature for the origin of listvenite, a substantial portion of the core description effort was dedicated to characterization of the complex veining history recorded in the hole. Dense veining is recorded in both lithologies. The density of 200/m. The density of veins >1 mm was 50-100/m, with somewhat higher densities recorded in serpentinite than in listvenite. In order of oldest to youngest, the main vein types in serpentinite are microscopic mesh-textured serpentine veins, macroscopic serpentine veins, carbonate-oxide veins, and carbonate veins. The vein paragenesis in listvenite is: early carbonate-oxide veins, followed by carbonate and carbonate-quartz veins, then late carbonate veins. The carbonate-oxide and carbonate veins are shared by the lithologies and hold clues to the transformation of ultramafic rocks to listvenite. Carbonate-oxide veins form a distinctive set that is interpreted to be the earliest record of carbonate formation in serpentinite. They contain Fe-oxide, usually hematite, on a medial line, with antitaxial magnesite crystals growing outward and showing terminations against wall rock minerals. Antitaxial textures may be evidence of positive reaction volumes. In serpentinite, secondary serpentine after earlier serpentine is common at vein margins. Carbonate-oxide veins are the earliest observed in listvenite, where they may form isolated veins to dense, aligned networks that impart a foliated texture. In some cases, they appear to predate replacement of serpentine by

Analysis of potential flooding in the education Jatinangor based approach morphology, land cover, and geology

Science.gov (United States)

Rifai, Achmad; Hadian, Sapari Dwi; Mufti, Iqbal Jabbari; Fathoni, Azmi Rizqi; Azy, Fikri Noor; Jihadi, Lutfan Harisan

2017-07-01

Jatinangor formerly an agricultural area dominated by rice field. Water in Jatinangor comes from a spring located in north Jatinangor or proximal region of Manglayang mountain to flow to the south and southwest Jatinangor up to Citarum River. Jatinangor plain that was once almost all the rice fields, but now become a land settlement that grew very rapidly since its founding colleges. Flow and puddle were originally be used for agricultural land, but now turned into a disaster risks for humans. The research method using qualitative methods with the weighing factor, scoring, and overlay maps. The cause of the flood is distinguished into two: the first is the natural factors such as the condition of landform, lithology, river flow patterns, and annual rainfall. The second is non-natural factors such as land cover of settlement, irrigation, and land use. The amount of flood risks using probability Gilbert White frequency, magnitude and duration of existing events then correlated with these factors. Based on the results of the study, were divided into 3 zones Jatinangor disaster-prone (high, medium, and safe). High flood zone is located in the South Jatinangor which covers an area Cikeruh Village, Sayang Village, Cipacing village, Mekargalih village, Cintamulya village, west of Jatimukti village, and South Hegarmanah village, has a dominant causative factor is the use of solid land, poor drainage, lithology lacustrine conditions with low permeability, and flat topography. Medium flood zone was located in the central and western regions covering Cibeusi village, Cileles village, south of Cilayung village, Hegarmanah village and Padjadjaran Region, has a dominant causative factor is rather dense land use, lithology breccias and Tuffaceous Sand with moderate permeability, topography is moderately steep. Safe flood zone is located in the east Jatinangor covering Jatiroke village, Cisepur village, east Hegarmanah village, has a dominant factor in the form of a rather steep

Physico-chemical assessment of borehole water used by schools in ...

African Journals Online (AJOL)

samie.amidou

2013-07-24

Jul 24, 2013 ... soil pore spaces and in fractures of lithologic formation. Groundwater quality ... of geological material through which groundwater moves and the quality of ... compounds such as magnesium, calcium and chlorides. However ...

Geochemistry and hydrogeochemical process of groundwater in the ...

African Journals Online (AJOL)

user

the aquifer system in the study area (lithology, structure, conditions and underground circulation ... rock types, quality of recharge water and inputs from sources other ...... hydrogeology of the carbonate peninsulas of Florida and Yucatan. J.

Quantifying the Forcing Factors Responsible for the Tectono-Geomorphological Evolution of Neogene Rift Basins, Baja California

Science.gov (United States)

El-Sobky, H. F.; Dorobek, S. L.

2005-12-01

The Gulf of California and its surrounding land areas provide a classic example of recently rifted continental lithosphere, where back-arc stretching of a continental volcanic arc has culminated in the ongoing seafloor spreading that characterizes the present-day axis of the gulf. The recent tectonic history of eastern Baja California, which includes most of the land area eastward of the main drainage divide that extends north-south along the length of the peninsula, has been dominated by oblique rifting that began at about 5 Ma. Thus, extensional tectonics, bedrock lithology, long-term climatic changes, and evolving surface processes have controlled the tectono-geomorphological evolution of the eastern part of the peninsula since 5 Ma. No previous studies, however, examined the effect of these combined factors on the current tectono-geomorphological characteristics of eastern Baja California. We assume that although long-term climate may have changed along the peninsula over the last several million years, precipitation amounts are likely to have changed in a similar way along the entire length of the peninsula, regardless of the long-term climatic trend. This suggests that climatic variation can be largely ruled out as an explanation for the geomorphologic variability between basins. In an attempt to quantify the factors that affected the geomorphologic development along the eastern side of Baja California, thirty-four drainage basins were extracted from a 15-m-resolution absolute digital elevation model (DEM). The stacked-vector method was applied to utilize the different terrain attributes (e.g., hillshaded relief, aspect, slope, etc.) for supervised classification of bedrock lithologies using object-oriented techniques. Stream-length gradient indices were then measured for the main stream in each of the basins. Bedrock lithologies and alluvium were plotted along the stream profiles to identify any relationship between lithology, structure, and stream gradient

The Cretaceous-Paleogene transition and Chicxulub impact ejecta in the northwestern Gulf of Mexico: Paleoenvironments, sequence stratigraphic setting and target lithologies

Science.gov (United States)

Schulte, Peter

2003-07-01

), and as microspar, suggesting that this area received ejecta mainly from shallow, carbonate-rich lithologies at the impact site on the Yucatán carbonate platform. Albeit the ejecta spherules are mostly altered to clay minerals and iron oxides, the microfacies and internal textures of the ejecta particles show a variety of distinct features, including welding and fusing of components and evidence for liquid immiscibility between silicic-silicic and carbonate-silicic melts. No evidence for binary mixing of ejecta phases was found. Therefore, it is assumed that ejecta in northeastern Mexico derived from less energetic parts of the ejecta curtain. The welding features of ejecta particles suggest an initial ground surge-like ejecta-dispersion mode. The specific morphological features and the compositional range of Chicxulub ejecta, as well as the results of petrological and rock magnetic characteristics reveal similarities to Chicxulub ejecta from K-P sections in the Gulf of Mexico area, the Caribbean, the Atlantic, the Pacific, and Northern America (Western Interior). In addition, Mg-rich smectite, K-feldspar, and iron oxide-rich microspherules are characteristic for the K-P boundary clay layer in sections from the Atlantic and Tethyan realm, suggestive of a relationship between the Chicxulub impact event and the basal K-P boundary clay layer. EJECTA DEPOSITS: The Chicxulub ejecta deposits are commonly associated with an event deposit that shows a complex succession of deposition from high-energetic (channelized) debris flows or turbidity currents derived from multiple source areas, followed by a period of decreasing current energy and intermittent periods of reworking. The uppermost parts of these deposits are often bioturbated, pointing to longer periods of deposition, as also sustained by the complex internal subdivision of the K-P event deposits. In northeastern Mexico, Chicxulub ejecta is also locally embedded within latest Maastrichtian marls, though common soft

Using Outcrop Exposures on the Road to Yellowknife Bay to Build a Stratigraphic Column, Gale Crater, Mars

Science.gov (United States)

Stack, K. M.; Grotzinger, J. P.; Sumner, D.; Ehlmann, B. L.; Milliken, R. E.; Eigenbrode, J. L.; Gupta, S.; Williams, R. M. E.; Kah, L. C.; Lewis, K. W.

2013-01-01

Since landing in Gale Crater on August 5, 2012, the Curiosity rover has driven 450 m east, descending approximately 15 m in elevation from the Bradbury landing site to Yellowknife Bay. Outcrop exposure along this drive has been discontinuous, but isolated outcrops may represent windows into underlying inplace stratigraphy. This study presents an inventory of outcrops targeted by Curiosity (Figs. 1-2), grouped by lithological properties observed in Mastcam and Navcam imagery. Outcrop locations are placed in a stratigraphic context using orbital imagery and first principles of stratigraphy. The stratigraphic models presented here represent an essential first step in understanding the relative age relationships of lithological units encountered at the Curiosity landing site. Such observations will provide crucial context for assessing habitability potential of ancient Gale crater environments and organic matter preservation.

OSL surface exposure dating of a lithic quarry in Tibet: Laboratory validation and application

DEFF Research Database (Denmark)

Gliganic, L.A.; Meyer, M.C.; Sohbati, R.

2018-01-01

developed OSL Surface exposure dating technique (OSL-Surf) to date flake scars at lithic quarry sites. We performed the first quantitative validation of the model describing the OSL-Surf dating technique using a controlled laboratory experiment. Our results show that longer laboratory bleaching durations......-depth profile that could be used to calibrate the model to estimate the exposure duration of a flake scar associated with human exploitation of the area. Finally, we observe that the μ parameter of the OSL-Surf model varies considerably between the laboratory-bleached and two naturally daylight-bleached...... datasets, despite having identical lithologies. We thus infer that, in addition to lithological controls, the μ parameter is primarily sensitive to the daylight irradiation geometry and only weakly dependent on spectrum of the incident light; this interpretation implies a narrow effective bleaching...

Diamond drilling for geologic information in the middle Precambrian basins in the western portion of northern Michigan. Final report

International Nuclear Information System (INIS)

Trow, J.

1979-10-01

Between September 26, 1977, and May 11, 1978, six initially vertical holes probed a total of 9896 feet (1109 feet or 11.2% in overburden, 155 feet or 1.6% in Precambrian Y mafic dikes, 8386 feet or 84.7% in Precambrian X Goodrich Quartzite and Michigamme Formation, and 246 feet or 2.5% in Precambrian W basement lithologies). In addition to normal examination of core, logging, and storing of core, the holes were extensively logged geophysically, acidized core was tested for phosphate content by ammonium molybdate, splits from five out of every thirty feet of core were subjected to chemical scrutiny, thin sections of all lithologies were examined, and radiometric determinations of geologic age were made for confirmation of Precambrian W basement which was encountered in each of the three basins in Marquette County

Systematic logging utilizing a log sheet designed for drill core descriptions. An example in uranium exploration activities

International Nuclear Information System (INIS)

Sasao, Eiji; Tsuruta, Tadahiko; Iida, Yoshimasa

2000-01-01

We describe the log sheets used during uranium exploration activities for unconformity-related uranium deposits by JNC. The purpose of using the logging sheets is to standardize the objects which all geologists must observe and for data quality assurance. The log sheets are a three-part set describing basement lithology, sandstone lithology and geotechnics. We devised our own log sheets to describe both the sandstone and the underlying basement rock when we started exploration in Athabasca Basin, Canada. We modified the sheets to gain a better understanding of the geological features related to uranium mineralization, and made final improvements to satisfy required quality based on the criteria of descriptive objects and accuracy. Use of the log sheets resulted in effective performance of core logging and improvement in the display of data. (author)

Deciphering the depositional environment of the laminated Crato fossil beds (Early Cretaceous, Araripe Basin, North-eastern Brazil)

DEFF Research Database (Denmark)

Heimhofer, Ulrich; Ariztegui, Daniel; Lenniger, Marc

2010-01-01

isotope geochemistry. Integration of lithological and petrographic evidence indicates that the bulk of the Nova Olinda limestone formed via authigenic precipitation of calcite from within the upper water column, most probably induced and/or mediated by phytoplankton and picoplankton activity...... equilibration with atmospheric CO2, probably in concert with stagnant conditions and low input of soil-derived carbon. Integration of lithological and isotopic evidence indicates a shift from closed to semi-closed conditions towards a more open lake system during the onset of laminite deposition in the Crato....... A significant contribution from a benthonic, carbonate-secreting microbial mat community is not supported by these results. Deposition took place under anoxic and, at least during certain episodes, hypersaline bottom water conditions, as evidenced by the virtually undisturbed lamination pattern, the absence...

Geomorphic and Geologic Controls of Geohazards induced by Nepal's 2015 Gorkha Earthquake

Science.gov (United States)

Kargel, J. S.; Leonard, G. J.; Shugar, D. H.; Haritashya, U.K.; Bevington, A.; Fielding, E. J.; Fujita, K.; Geertsema, M.; Miles, E. S.; Steiner, J.;

A new algorithm for coding geological terminology

Science.gov (United States)

Apon, W.

The Geological Survey of The Netherlands has developed an algorithm to convert the plain geological language of lithologic well logs into codes suitable for computer processing and link these to existing plotting programs. The algorithm is based on the "direct method" and operates in three steps: (1) searching for defined word combinations and assigning codes; (2) deleting duplicated codes; (3) correcting incorrect code combinations. Two simple auxiliary files are used. A simple PC demonstration program is included to enable readers to experiment with this algorithm. The Department of Quarternary Geology of the Geological Survey of The Netherlands possesses a large database of shallow lithologic well logs in plain language and has been using a program based on this algorithm for about 3 yr. Erroneous codes resulting from using this algorithm are less than 2%.

Alteration zone Mapping in the Meiduk and Sar Cheshmeh Porphyry Copper Mining Districts of Iran using Advanced Land Imager (ALI Satellite Data

Directory of Open Access Journals (Sweden)

A. Beiranvand Pour

2015-10-01

Full Text Available This study evaluates the capability of Earth Observing-1 (EO1 Advanced Land Imager (ALI data for hydrothermal alteration mapping in the Meiduk and Sar Cheshmeh porphyry copper mining districts, SE Iran. Feature-oriented principal components selection, 4/2, 8/9, 5/4 band ratioing were applied to ALI data for enhancing the hydrothermally altered rocks associated with porphyry copper mineralization, lithological units and vegetation. Mixture-tuned matched-filtering (MTMF was tested to discriminate the hydrothermal alteration areas of porphyry copper mineralization from surrounding environment using the shortwave infrared bands of ALI. Results indicate that the tested methods are able to yield spectral information for identifying vegetation, iron oxide/hydroxide and clay minerals, lithological units and the discrimination of hydrothermally altered rocks from unaltered rocks using ALI data.

Stratigraphy of the Harwell boreholes

International Nuclear Information System (INIS)

Gallois, R.W.; Worssam, B.C.

1983-12-01

Seven boreholes, five of them partially cored, were drilled at the Atomic Energy Research Establishment at Harwell as part of a general investigation to assess the feasibility of storing low- and intermediate-level radioactive waste in underground cavities. Two of the deeper boreholes were almost wholly cored to provide samples for hydrogeological, hydrochemical, mineralogical, geochemical, geotechnical, sedimentological and stratigraphical studies to enable variations in lithology and rock properties to be assessed, both vertically and laterally, and related to their regional geological setting. This report describes the lithologies, main faunal elements and stratigraphy of the Cretaceous, Jurassic, Triassic and Carboniferous sequences proved in the boreholes. More detailed stratigraphical accounts of the late Jurassic and Cretaceous sequences will be prepared when current studies of the faunal assemblages are complete. (author)

Geochemical Survey of Pernambuco

International Nuclear Information System (INIS)

Horowitz, A.; Duarte, P.J.; Almeida, M.G. de; Medeiros, M.O.

1988-01-01

The area studied i this work is located in a triangle formed by the Sibiro and Boca da Mata Sugar-Mills and Serinhaem country. In the Cabo Formation the search determinated conglomerates, arcos and clays. Although the highest geochemical activity have been done in the decomposed crystalin, and the values from Cabo Formation don't be encourager, this formation has lithology compatible with uranium mineralization. The Cabo Formation's sediments presents lithologic variations very expressives, with conglomerates, arcoses and clay silts, which determinate the choise of the area. This area presented favorable to uranium prospecting and to others elements interesting to ragional geochemistry. The atomic absorption analysis, fluorimetry and spectrometry were done for the following elements: Zn, V, Ti, Ni, Pb, Mn, Ga, Cu, Co, Bi, Ag, B, Mo, and U. (C.D.G.) [pt

Landslides triggered by the storm of November 3-5, 1985, Wills Mountain Anticline, West Virginia and Virginia: Chapter C in Geomorphic studies of the storm and flood of November 3-5, 1985, in the upper Potomac and Cheat River basins in West Virginia and Virginia

Science.gov (United States)

Jacobson, Robert B.; McGeehin, John P.; Cron, Elizabeth D.; Carr, Carolyn E.; Harper, John M.; Howard, Alan D.

1993-01-01

More than 3,000 landslides were triggered by heavy rainfall in the central Appalachian Mountains of West Virginia and Virginia, November 3-5, 1985. These landslides provided the opportunity to study spatial controls on landslides, magnitude and frequency of triggering events, and the effects of landslides on flood-induced geomorphic change. The study area consists of parts of the Wills Mountain anticline, a major NE-trending structure in the central Appalachians, and a portion of the adjacent Appalachian Plateau. Across the anticline and adjacent plateau, bedrock lithologies vary markedly and include pure marine limestone, marine shale, deltaic mudstone/sandstone sequences, and orthoquartzites. Because of the geologic structure, bedrock lithology varies little along strike. The spatial distribution of landslides triggered by the storm was controlled primarily by rainfall, bedrock lithology, surficial lithology, land cover, and slope morphology. The triggering rainfall was of moderate intensity and long duration. Two-day storm totals varied from 170 mm to more than 240 mm in the study area. Most landslides occurred at the northeast end of the study area, where 48-h rainfall totals were in excess of 200 mm. Different rainfall thresholds are apparent for triggering landslides on different bedrock lithologies. The highest density of landslides occurred in shallow colluvium and residuum of the Reedsville Shale (Ordovician), followed by regolith of the Greenbriar and Mauch Chunk Groups (Mississippian). Most of the landslides in these fine-grained regoliths were shallow slides and slumps, many of which transformed to mudflows and delivered sediment directly to streams; a smaller number of debris avalanches were triggered high on quartzite ridges.Instability of colluvium and residuum derived from the Reedsville Shale, compared with regolith from four other fine-grained bedrock lithologies, is attributable to its low strength combined with moderate infiltration rates that

Geological model of the ONKALO area version 0

International Nuclear Information System (INIS)

Paananen, M.; Paulamaeki, S.; Gehoer, S.; Kaerki, A.

2006-03-01

The geological model of the ONKALO area is composed of four submodels: ductile deformation model, lithological model, brittle deformation model and alteration model. The ductile deformation model describes and models the products of polyphase ductile deformation, which facilitates the definition of dimensions and geometrical properties of individual lithological units determined in the lithological model. The lithological model describes the properties of rock units that can be defined on the basis the migmatite structures, textures and modal compositions. The brittle deformation model describes the products of multiple phases of brittle deformation, and the alteration model describes the types, occurrence and the effects of the hydrothermal alteration. On the basis of refolding and crosscutting relationships, the metamorphic supracrustal rocks have been subject to five stages of ductile deformation. This resulted in a pervasive, composite foliation which shows a rather constant attitude in the ONKALO area. Based on observations in outcrops, investigation trenches and drill cores, 3D modelling of the lithological units is carried out assuming that the contacts are quasiconcordant. Using this assumption, the strike and dip of the foliation has been used as a tool to correlate the lithologies between the drillholes, and from surface and tunnel outcrops to drillholes. Consequently, the strike and dip of the foliation has been used as a tool, through which the lithologies have been correlated between the drillholes and from surface to drillholes. The rocks at Olkiluoto can be divided into two major groups: (1) supracrustal high-grade metamorphic rocks including various migmatitic gneisses, homogeneous tonaliticgranodioritic- granitic gneisses, mica gneisses and quartzitic gneisses, and mafic gneisses, (2) igneous rocks, including pegmatitic granites and diabase dykes. The migmatitic gneisses can further be divided into three subgroups in terms of the type of migmatite

Ogallala Bedrock Data Enhancement

Data.gov (United States)

Kansas Data Access and Support Center — This data set provides an enhanced estimate of the bedrock elevation of the Ogallala Aquifer in Kansas based on lithologic logs from a variety of sources. The data...

Journal of Applied Sciences and Environmental Management - Vol ...

African Journals Online (AJOL)

... Oil on Hematology, Renal and Liver Status of Auto- Mechanics of Benin-City, Nigeria .... Hygiene Assessment of the Performance of Food Safety Management ... Cross plotting of Rock Properties for Fluid and Lithology Discrimination using ...

The geological map of Canelones Department scale 1:1000.000

International Nuclear Information System (INIS)

Spoturno, J.; Oyhantcabal, P.; Goso, C.; Aubet, N.; Cazaux; S; Huelmo, S.; Morales, E.; Loureiro, J.

2004-01-01

The geological map of Canelones Department (Uruguay), scale 1:100.000 is presented. This map shows the distribution of the proterozoic, mesozoic and cenozoic lithological units. A stratigraphic division of this region is included [es

The geological map of Montevideo Department scale 1:50.000

International Nuclear Information System (INIS)

Spoturno, J.; Oyhantcabal, P.; Goso, C.; Aubet, N.; Cazaux; S; Huelmo, S.; Morales, E.; Loureiro, J.

2004-01-01

The geological map of Montevideo Department (Uruguay), scale 1:50.000 is presented. This map shows the distribution of the proterozoic, mesozoic and cenozoic lithological units. A stratigraphic division of this region is included [es

A numerical reference model for themomechanical subduction

DEFF Research Database (Denmark)

Quinquis, Matthieu; Chemia, Zurab; Tosi, Nicola

2010-01-01

Building an advanced numerical model of subduction requires choosing values for various geometrical parameters and material properties, among others, the initial lithosphere thicknesses, representative lithological types and their mechanical and thermal properties, rheologies, initial temperature...

A description of sediment cores from the Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Setty, M.G.A.P.

environment; core no. 4 has oolitic layers with intercalations of clayey material and contains few fossils; and core no. 5 is characterized by two distinct lithologies, a definite stratigraphic break and a moderate concentration of fossils...

ASTER spectral analysis and lithologic mapping of the Khanneshin carbonatite volcano, Afghanistan

Science.gov (United States)

Mars, John C.; Rowan, Lawrence C.

2011-01-01

Advanced Spaceborne Thermal and Reflection Radiometer (ASTER) data of the early Quaternary Khanneshin carbonatite volcano located in southern Afghanistan were used to identify carbonate rocks within the volcano and to distinguish them from Neogene ferruginous polymict sandstone and argillite. The carbonatitic rocks are characterized by diagnostic CO3 absorption near 11.2 μm and 2.31–2.33 μm, whereas the sandstone, argillite, and adjacent alluvial deposits exhibit intense Si-O absorption near 8.7 μm caused mainly by quartz and Al-OH absorption near 2.20 μm due to muscovite and illite.Calcitic carbonatite was distinguished from ankeritic carbonatite in the short wave infrared (SWIR) region of the ASTER data due to a slight shift of the CO3 absorption feature toward 2.26 μm (ASTER band 7) in the ankeritic carbonatite spectra. Spectral assessment using ASTER SWIR data suggests that the area is covered by extensive carbonatite flows that contain calcite, ankerite, and muscovite, though some areas mapped as ankeritic carbonatite on a preexisting geologic map were not identified in the ASTER data. A contact aureole shown on the geologic map was defined using an ASTER false color composite image (R = 6, G = 3, B = 1) and a logical operator byte image. The contact aureole rocks exhibit Fe2+, Al-OH, and Fe, Mg-OH spectral absorption features at 1.65, 2.2, and 2.33 μm, respectively, which suggest that the contact aureole rocks contain muscovite, epidote, and chlorite. The contact aureole rocks were mapped using an Interactive Data Language (IDL) logical operator.A visible through short wave infrared (VNIR-SWIR) mineral and rock-type map based on matched filter, band ratio, and logical operator analysis illustrates: (1) laterally extensive calcitic carbonatite that covers most of the crater and areas northeast of the crater; (2) ankeritic carbonatite located southeast and north of the crater and some small deposits located within the crater; (3) agglomerate that primarily covers the inside rim of the crater and a small area west of the crater; (4) a crater rim that consists mostly of epidote-chlorite-muscovite–rich metamorphosed argillite and sandstone; and (5) iron (Fe3+) and muscovite-illite–rich rocks and iron-rich eolian sands surrounding the western part of the volcano. The thermal infrared (TIR) rock-type map illustrates laterally extensive carbonatitic and mafic rocks surrounded by quartz-rich eolian and fluvial reworked sediments. In addition, the combination of VNIR, SWIR, and TIR data complement one another in that the TIR data illustrate more laterally extensive rock types and the VNIR-SWIR data distinguish more specific varieties of rocks and mineral mixtures.

Lithology, stratigraphy and geochemistry of sediments: Sedimentary geology of the deformation zone

Digital Repository Service at National Institute of Oceanography (India)

Muradmaa, I.O.; Levitan, M.A.; Reddy, N.P.C.; Emelyanov, E.M; Jafri, S.H.

stream_size 10 stream_content_type text/plain stream_name Memoir_Geol_Soc_India_1998_39_177.pdf.txt stream_source_info Memoir_Geol_Soc_India_1998_39_177.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

Method and apparatus for neutron induced gamma ray logging for lithology identificaion

International Nuclear Information System (INIS)

Oliver, D.W.; Culver, R.B.

1979-01-01

A pulsed neutron generator in a well logging instrument is pulsed at a clock frequency of 20 KHz. Inelastic scatter gamma rays are detected during a first time interval coinciding with the neutron source being on and capture gamma rays are measured during a second interval subsequent to the end of each neutron burst. Only a single detected pulse, assuming detection occurs, is transmitted during each of the two detection intervals. Sync pulses are generated in the well logging instrument scaled down to a frequency of 200 Hz for transmission to the earth's surface. At the earth's surface, the scaled-down sync pulses are applied to a phase-locked loop system for regenerating the sync pulses to the same frequency as that of the clock frequency used to pulse the neutron source and to open the detection gates in the borehole instrument. The regenerated sync pulses are used in the surface instrumentation to route the pulses occurring in the inelastic interval into one section of a multichannel analyzer memory and the pulses occurring in the capture interval into another section of the multichannel analyzer. The use of memory address decoders, subtractors and ratio circuits enables both a carbon/oxygen ratio and a silicon/calcium ratio to be struck, substantially independent of the chlorine content of the borehole and formation

Method and apparatus for neutron induced gamma ray logging for lithology identification

International Nuclear Information System (INIS)

Oliver, D.W.; Culver, R.B.

1981-01-01

The patent describes a neutron-gamma well logging technique which can distinguish between sandstone and limestone formations irrespective of water salinity in the formation. The formation surrounding a borehole is irradiated by fast neutrons and the resulting gamma rays are counted. The gamma rays are converted to electrical signals in three distinct steps; the first two signals result from gamma rays associated with calcium content of the formation and the third signal from gamma rays associated with silicon content. Gamma rays resulting from irradiation of calcium are counted at two non-contiguous energy bands. (O.T.)

Preliminary feasibility study on storage of radioactive wastes in Columbia River basalts. Volume II

Energy Technology Data Exchange (ETDEWEB)

,

1976-11-01

Volume II comprises four appendices: analytical data and sample locations for basalt flow type localities; Analytical data and sample locations for measured field sections in Yakima basalts; core hole lithology and analytical data; and geophysical logs. (LK)

Using lame's petrophysical parameters for fluid detection and ...

African Journals Online (AJOL)

AVO synthetic gather models were created using various gas/brine/oil ... a quantitative extraction of rock properties to clearly determine lithology and fluids. ... an improved separation of high porosity sands from shale was also achieved using ...

Water quality of the Chhoti Gandak River using principal component ...

Indian Academy of Sciences (India)

; therefore water samples were collected to analyse its quality along the entire length of Chhoti Gandak. River. The principal components of water quality are controlled by lithology, gentle slope gradient, poor drainage, long residence of water, ...

Lithology, hydro-dynamism and thermicity in the multi-layer sedimentary system intersected by the Andra deep borehole of Montiers-sur-Saulx (Meuse, France)

International Nuclear Information System (INIS)

Landrein, Philippe; Vigneron, Georges; Delay, Jacques; Lebon, Patrick; Pagel, Maurice

2013-01-01

their own sampling on cores dedicated to the Andra studies as well as on cores that were positioned to suit their own research themes. The Callovo-Oxfordian and the upper part of the Dogger were cored continuously from 526 m to 770 m in depth. The method used for the lower part, from 770 to 2001 m (MD),was percussion air drilling with punctual core extraction for certain horizons. Numerous logs were carried out during drilling, others were differed, and two thermal logs were performed 9 months after drilling: These logs and the cores helped to establish a stratigraphic log consistent with previous Andra drilling results in the Dogger and the Malm, as well as the Chevillon 1 drilling for the Liassic and Triassic units. Information obtained from the deep borehole confirmed the progressive northeasterly thickening of the Callovo-Oxfordian layer as well as its lithological vertical and horizontal consistency. The measurements of hydraulic transmissivity in Callovo-Oxfordian formation show the same range than in other places in the Transposition zone. In the Dogger, a clear link between the permeability of certain levels and the depositional environments was brought to light. For the deep formations (Lias and Trias), the series is consistent with the one deduced from previous drillings. Only the formation of the lower Keuper 'Marnes irisees' is thicker than expected. The reconstruction of the thickness of the formations, achieved thanks to the seismic campaign and nearest oil drillings, shows that the EST433 borehole is located in a hollow area where the Keuper formations are thicker. The borehole results show that the upper and middle Lias and Trias facies have a very low porosity and that only the lower Trias contains aquiferous levels. Thus, a series of a thousand meters with no significant porosity separates the Dogger aquifer from that of the lower Trias. Interpretation of the seismic profiles reveals the existence of faults, mainly in the western part of the zone, but

Definition of a critical confining zone using surface geophysical methods

International Nuclear Information System (INIS)

Eddy-Dilek, C.A.; Hoekstra, P.; Harthill, N.; Blohm, M.; Phillips, D.R.

1996-01-01

Definition of the hydrogeologic framework in layered sediments of fluvial and deltaic origin is a difficult challenge for environmental characterization and remediation programs due to the lithologic and stratigraphic heterogeneities inherent in these settings. These heterogeneties often control contaminant transport and the effectiveness of remediation alternatives, Surface geophysical surveys can be cost-effective methods for characterization, but individual methods have inherent limitations in resolution and sensitivity. A synergistic approach, utilizing two geophysical survey methods was applied, to define and examine the nature and extent of a deep confining zone of regulatory importance, the Crouch Branch Confining Unit, in Coastal Plain sediments at the Savannah River Site. TDEM accurately maps the overall conductance (product of thickness and electrical conductivity) of a confining zone clay facies; from variation in conductance, changes in lithology of the conforming zone can be inferred. Shear wave seismic reflection surveys map the depth to the clay layers, and the clay layer thickness, but provides little information on the lithologic nature of the confining zone. Integrated interpretation of the combined data set (including all available borehole logs) allows for delineation of the lateral and vertical extent of clay-dominated zones, sand-dominated zones, key stratigraphic horizons, and erosional features associated with unconformities. This approach has resulted in the collection of critical information that will be used to optimize remedial system design, representing a significant cost savings to environmental restoration programs at the Savannah River Site

Geology of the Early Arikareean sharps formation on the Pine Ridge Indian Reservation and surrounding areas of South Dakota and Nebraska.

Science.gov (United States)

McConnell, Thomas H; Dibenedetto, Joseph N

2012-01-01

Based on geologic mapping, measured sections, and lithologic correlations, the local features of the upper and lower type areas of the Early Arikareean (30.8-20.6 million years ago) Sharps Formation are revised and correlated. The Sharps Formation above the basal Rockyford Member is divided into two members of distinct lithotypes. The upper 233 feet of massive siltstones and sandy siltstones is named the Gooseneck Road Member. The middle member, 161 feet of eolian volcaniclastic siltstones with fluvially reworked volcaniclastic lenses and sandy siltstone sheets, is named the Wolff Camp Member. An ashey zone at the base of the Sharps Formation is described and defined as the Rockyford Ash Zone (RAZ) in the same stratigraphic position as the Nonpareil Ash Zone (NPAZ) in Nebraska. Widespread marker beds of fresh water limestones at 130 feet above the base of the Sharps Formation and a widespread reddish-brown clayey siltstone at 165 feet above the base of the Sharps Formation are described. The Brown Siltstone Beds of Nebraska are shown to be a southern correlative of the Wolff Camp Member and the Rockyford Member of the Sharps Formation. Early attempts to correlate strata in the Great Plains were slow in developing. Recognition of the implications of the paleomagnetic and lithologic correlations of this paper will provide an added datum assisting researchers in future biostratigraphic studies. Based on similar lithologies, the Sharps Formation, currently assigned to the Arikaree Group, should be reassigned to the White River Group.

Stochastic hydrogeologic units and hydrogeologic properties development for total-system performance assessments. Yucca Mountain Site Characterization Project

International Nuclear Information System (INIS)

Schenker, A.R.; Guerin, D.C.; Robey, T.H.; Rautman, C.A.; Barnard, R.W.

1995-09-01

A stochastic representation of the lithologic units and associated hydrogeologic parameters of the potential high-level nuclear waste repository are developed for use in performance-assessment calculations, including the Total-System Performance Assessment for Yucca Mountain-SNL Second Iteration (TSPA-1993). A simplified lithologic model has been developed based on the physical characteristics of the welded and nonwelded units at Yucca Mountain. Ten hydrogeologic units are developed from site-specific data (lithologic and geophysical logs and core photographs) obtained from the unsaturated and saturated zones. The three-dimensional geostatistical model of the ten hydrogeologic units is based on indicator-coding techniques and improves on the two-dimensional model developed for TSPA91. The hydrogeologic properties (statistics and probability distribution functions) are developed from the results of laboratory tests and in-situ aquifer tests or are derived through fundamental relationships. Hydrogeologic properties for matrix properties, bulk conductivities, and fractures are developed from existing site specific data. Extensive data are available for matrix porosity, bulk density, and matrix saturated conductivity. For other hydrogeologic properties, the data are minimal or nonexistent. Parameters for the properties are developed as beta probability distribution functions. For the model units without enough data for analysis, parameters are developed as analogs to existing units. A relational, analytic approach coupled with bulk conductivity parameters is used to develop fracture parameters based on the smooth-wall-parallel-plate theory. An analytic method is introduced for scaling small-core matrix properties to the hydrogeologic unit scales

Geohydrologic data collected from shallow neutron-access boreholes and resultant-preliminary geohydrologic evaluations, Yucca Mountain area, Nye County, Nevada

International Nuclear Information System (INIS)

Blout, D.O.; Hammermeister, D.P.; Loskot, C.L.; Chornack, M.P.

1994-01-01

In cooperation with the US Department of Energy, 74 neutron-access boreholes were drilled in and near the southwestern part of the Nevada Test Site, Nye County, Nevada. Drilling, coring, sample collection and handling, and lithologic and preliminary geohydrologic data are presented in this report. The boreholes were drilled in a combination of alluvium/colluvium, ash-flow tuff, ash-fall tuff, or bedded tuff to depths of 4.6 to 36.6 meters. Air was used as a drilling medium to minimize disturbance of the water content and water potential of drill cuttings, core, and formation rock. Drill cuttings were collected at approximately 0.6-meter intervals. Core was taken at selected intervals from the alluvium/colluvium using drive-coring methods and from tuff using rotary-coring methods. Nonwelded and bedded tuffs were continuously cored using rotary-coring methods. Gravimetric water-content and water-potential values of core generally were greater than those of corresponding drill cuttings. Gravimetric water-content, porosity, and water-potential values of samples generally decreased, and bulk density values increased, as the degree of welding increased. Grain-density values remained fairly constant with changes in the degree of welding. A high degree of spatial variability in water-content and water-potential profiles was noted in closely spaced boreholes that penetrate similar lithologic subunits and was also noted in adjacent boreholes located in different topographic positions. Variability within a thick lithologic unit usually was small. 18 refs., 21 figs., 17 tabs

Sedimentary environments in the south-western Barents Sea during the last deglaciation and the Holocene: a case study outside the Ingøydjupet trough

Directory of Open Access Journals (Sweden)

Mauro Pau

2016-05-01

Full Text Available A lithological and foraminiferal study of newly acquired sediment cores outside the Ingøydjupet (Ingøy Deep trough has been carried out to improve constraints on the last deglacial history in the south-western Barents Sea. Three lithofacies and three foraminiferal facies were identified. The lowermost lithological unit is a diamicton interpreted as glacial till. It contains a low-abundance, ecologically mixed foraminiferal assemblage, presumably resulting from glacial reworking. Above the diamicton, a layer of ice-rafted debris (IRD, likely associated with intensive iceberg production, marks the initial destabilization of the marine-based ice sheet. At this time, ca. 15.6–15.0 Ky B.P., opportunistic foraminiferal species Nonionellina labradorica and Stainforthia spp. reached peak abundance. During the south-western Barents Sea ice-margin retreat, presumably corresponding to the Bølling interstadial, a sequence of glaciomarine laminations was deposited conformably on the layer of IRD. Sedimentation rates were apparently high (estimated about 0.4 cm per year and the foraminiferal fauna was dominated by Elphidium spp. and Cassidulina reniforme, species common for glacier-proximal environments. A hiatus at the top of the deglacial unit is likely linked to the high bottom-current activity associated with a strengthened inflow of Atlantic water masses into the Barents Sea. The uppermost lithological unit is represented by the Holocene marine sandy mud. It contains a high-abundance, high-diversity foraminiferal fauna with common cassidulinids, Cibicides spp., Epistominella pusilla and planktic species.

Controls of Soil Spatial Variability in a Dry Tropical Forest.

Directory of Open Access Journals (Sweden)

Sandeep Pulla

Full Text Available We examined the roles of lithology, topography, vegetation and fire in generating local-scale (<1 km2 soil spatial variability in a seasonally dry tropical forest (SDTF in southern India. For this, we mapped soil (available nutrients, Al, total C, pH, moisture and texture in the top 10 cm, rock outcrops, topography, all native woody plants ≥1 cm diameter at breast height (DBH, and spatial variation in fire frequency (times burnt during the 17 years preceding soil sampling in a permanent 50-ha plot. Unlike classic catenas, lower elevation soils had lesser moisture, plant-available Ca, Cu, Mn, Mg, Zn, B, clay and total C. The distribution of plant-available Ca, Cu, Mn and Mg appeared to largely be determined by the whole-rock chemical composition differences between amphibolites and hornblende-biotite gneisses. Amphibolites were associated with summit positions, while gneisses dominated lower elevations, an observation that concurs with other studies in the region which suggest that hillslope-scale topography has been shaped by differential weathering of lithologies. Neither NO3(--N nor NH4(+-N was explained by the basal area of trees belonging to Fabaceae, a family associated with N-fixing species, and no long-term effects of fire on soil parameters were detected. Local-scale lithological variation is an important first-order control over soil variability at the hillslope scale in this SDTF, by both direct influence on nutrient stocks and indirect influence via control of local relief.

Hierarchical modeling of indoor radon concentration: how much do geology and building factors matter?

International Nuclear Information System (INIS)

Borgoni, Riccardo; De Francesco, Davide; De Bartolo, Daniela; Tzavidis, Nikos

2014-01-01

Radon is a natural gas known to be the main contributor to natural background radiation exposure and only second to smoking as major leading cause of lung cancer. The main concern is in indoor environments where the gas tends to accumulate and can reach high concentrations. The primary contributor of this gas into the building is from the soil although architectonic characteristics, such as building materials, can largely affect concentration values. Understanding the factors affecting the concentration in dwellings and workplaces is important both in prevention, when the construction of a new building is being planned, and in mitigation when the amount of Radon detected inside a building is too high. In this paper we investigate how several factors, such as geologic typologies of the soil and a range of building characteristics, impact on indoor concentration focusing, in particular, on how concentration changes as a function of the floor level. Adopting a mixed effects model to account for the hierarchical nature of the data, we also quantify the extent to which such measurable factors manage to explain the variability of indoor radon concentration. - Highlights: • It is assessed how the variability of indoor radon concentration depends on buildings and lithologies. • The lithological component has been found less relevant than the building one. • Radon-prone lithologies have been identified. • The effect of the floor where the room is located has been estimated. • Indoor radon concentration have been predicted for different dwelling typologies

Geological map of Uruguay Esc 1,100,000. Guayabos Sheet N-15

International Nuclear Information System (INIS)

Gancio, F.; Ford, I.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Guayabos) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils of Arapey, Guichon, Mercedes and Asencio formations in the Cretaceous period

Fadiya et al (8)

African Journals Online (AJOL)

big timmy

Ditch cutting samples from depth interval 1440 – 2720 metres in Well AM-2, onshore Niger Delta were studied for their lithology ... out in the onshore and shallow offshore areas of the Niger .... foraminiferal processing procedures. Thirty (30).

Morphogenetic controls on the distribution of the littoral placers along central west coast of India

Digital Repository Service at National Institute of Oceanography (India)

Gujar, A.R.

in more fluvial erosion, however, overall sediment input is low due to the lithological variations along their courses. Headlands and plunging cliffs favour the sediment deposition by impeding the long shore drift and the sediments passing headlands enter...

A shallow seismic reflection study of the Gulf of Kutch, northwest India - Observations on its structural evolution

Digital Repository Service at National Institute of Oceanography (India)

Rao, D.G.

the gulf. Correlation of onshore well-log lithology (near Kadach 75 km from the study area) with subbottom reflectors revealed a comparable sequence, this sequence consisting of sandstone, brown clays and limestones. The relict corals are submerged due...

Shear-Rate-Dependent Behavior of Clayey Bimaterial Interfaces at Landslide Stress Levels

Science.gov (United States)

Scaringi, Gianvito; Hu, Wei; Xu, Qiang; Huang, Runqiu

2018-01-01

The behavior of reactivated and first-failure landslides after large displacements is controlled by the available shear resistance in a shear zone and/or along slip surfaces, such as a soil-bedrock interface. Among the factors influencing the resistance parameter, the dependence on the shear rate can trigger catastrophic evolution (rate-weakening) or exert a slow-down feedback (rate-strengthening) upon stress perturbation. We present ring-shear test results, performed under various normal stresses and shear rates, on clayey soils from a landslide shear zone, on its parent lithology and other lithologies, and on clay-rock interface samples. We find that depending on the materials in contact, the normal stress, and the stress history, the shear-rate-dependent behaviors differ. We discuss possible models and underlying mechanisms for the time-dependent behavior of landslides in clay soils.

HCMM imagery for the discrimination of rock types, the detection of geothermal energy sources and the assessment of soil moisture content in western Queensland and adjacent parts of New South Wales and South Australia

Science.gov (United States)

Cole, M. M. (Principal Investigator)

1980-01-01

The author has identified the following significant results. Day-visible and day-IR imagery of northwest Queensland show that large scale geological features like the Mitakoodi anticlinorium, which involves rocks of contrasting lithological type, can be delineated. North of Cloncurry, the contrasting lithological units of the Knapdale quartzite and bedded argillaceous limestones within the Proterozoic Corella sequence are clearly delineated in the area of the Dugald River Lode. Major structural features in the Mount Isa area are revealed on the day-visible cover. Which provides similar but less detailed information than the LANDSAT imagery. The day-IR cover provides less additional information for areas of outcropping bedrock than had been expected. Initial studies of the day-IR and night-IR cover for parts of South Australia suggest that they contain additional information on geology compared with day-visible cover.

Utilizing HyspIRI Prototype Data for Geological Exploration Applications: A Southern California Case Study

Directory of Open Access Journals (Sweden)

Wendy M. Calvin

2016-02-01

Full Text Available The purpose of this study was to demonstrate the value of the proposed Hyperspectral Infrared Imager (HyspIRI instrument for geological mapping applications. HyspIRI-like data were collected as part of the HyspIRI airborne campaign that covered large regions of California, USA, over multiple seasons. This work focused on a Southern California area, which encompasses Imperial Valley, the Salton Sea, the Orocopia Mountains, the Chocolate Mountains, and a variety of interesting geological phenomena including fumarole fields and sand dunes. We have mapped hydrothermal alteration, lithology and thermal anomalies, demonstrating the value of this type of data for future geologic exploration activities. We believe HyspIRI will be an important instrument for exploration geologists as data may be quickly manipulated and used for remote mapping of hydrothermal alteration minerals, lithology and temperature anomalies.

Report of exploration in the mining reserve N XIV

International Nuclear Information System (INIS)

Spoturno, J.; Lara, P.

1991-01-01

This report is about the geological exploration in the mining reserve N X IV. There were recognized basically three units : 1) granitic basement neisico migma tic. 2) lithologic group a md 3) a unit of quartz feldspar granitoid rocks.

Tri-State Synfuels Project Review: Volume 9A. Subcontract information. [Proposed Henderson, Kentucky coal to gasoline plant; water supply and civil engineering subcontracts

Energy Technology Data Exchange (ETDEWEB)

1982-06-01

Volume 9A considers subcontract work done at the site involving hydrogeological studies with respect to water supply and geotechnical work with respect to the building foundations necessary based on boreholes drilled and the lithology of the area. (LTN)

Effects of Weathering on TIR Spectra and Rock Classification

Science.gov (United States)

McDowell, M. L.; Hamilton, V. E.; Riley, D.

2006-03-01

Changes in mineralogy due to weathering are detectable in the TIR and cause misclassification of rock types. We survey samples over a range of lithologies and attempt to provide a method of correction for rock identification from weathered spectra.

Report of exploration in the mining reserve N XIV; Informe de exploracion en la reserva minera XIV

Energy Technology Data Exchange (ETDEWEB)

Spoturno, J.; Lara, P.

1991-07-01

This report is about the geological exploration in the mining reserve N X IV. There were recognized basically three units : 1) granitic basement neisico migma tic. 2) lithologic group a md 3) a unit of quartz feldspar granitoid rocks.

Method and device for measuring formation characteristics of geological formations

International Nuclear Information System (INIS)

Antkiw, S.; Murphy, R.D.

1981-01-01

A well-logging system is described which uses a pulsed neutron source and which by combining measurements of gamma spectra and neutron characteristics enables such parameters as salinity, porosity, water saturation, lithology and schistosity to be registered directly. (JIW)

Geological map of Uruguay Esc 1,100,000. Cololo Sheet 0-19

International Nuclear Information System (INIS)

Morales, H.; Ford, I.; Montana, J.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Cololo) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils of Holocene, Oligocene and upper Cretaceous in Asencio and Fray Bentos formations

Forest composition in Mediterranean mountains is projected to shift along the entire elevational gradient under climate change

DEFF Research Database (Denmark)

Ruiz-Labourdette, Diego; Nogues, David Bravo; Ollero, Helios Sáinz

2012-01-01

species) as functions of climate, lithology and availability of soil water using generalized linear models (logistic regression) and machine learning models (gradient boosting). Using multivariate ordination of a matrix of presence/absence of tree species obtained under two Intergovernmental Panel...

Influence of production method on physical and chemical properties of Kumkol petroleum

International Nuclear Information System (INIS)

Ajdarbaev, A.S.; Nadirov, A.N.; Musaeva, Z. G.

1997-01-01

Industrial petroleum and gas content of Kumkol deposit is determined. It dated to Lower Neocomian and Upper Jurassic terrigenous stage sediments. It is determined, that its lithologic characteristics are very different. That is explained by various condition of sedimentation. (author)

Geological map of Uruguay scale 1.100.000 Canada Nieto Sheet P-23

International Nuclear Information System (INIS)

Ferrando, L; Eugui, W; Cabrera, Z; Elias, R

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Canada Nieto) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils of the pre devoniam period in the Mercedes , Asencio and Fray Bentos formations

A review of reflection seismic investigations in three major metallogenic regions: The Kevitsa Ni–Cu–PGE district (Finland), Witwatersrand goldfields (South Africa), and the Bathurst Mining Camp (Canada)

CSIR Research Space (South Africa)

Malehmir, A

2014-01-01

Full Text Available -resolution image of the subsurface and information about structural and lithological relationships that control mineral deposits. The method has also become an attractive geophysical tool for deep exploration and mine planning. In this paper, we review the use...

Barrier Systems

NARCIS (Netherlands)

Heteren, S. van

2015-01-01

Barrier-system dynamics are a function of antecedent topography and substrate lithology, Relative sea-level (RSL) changes, sediment availability and type, climate, vegetation type and cover, and various aero- and hydrodynamic processes during fair-weather conditions and extreme events. Global change

Permian Triassic palynofloral transition in Chintalapudi area ...

Indian Academy of Sciences (India)

The entire 606 m-thick sedimentary sequence in borecore MCP-7 from Chintalapudi area, Chintalapudi sub-basin has been lithologically designated as Kamthi Formation. However, the palynological investigation revealed five distinct palynoassemblages, which essentially fall under two groups, one group ...

Exploration and grade control neutron logging

International Nuclear Information System (INIS)

Eisler, P.L.

1982-01-01

Techniques used in neutron logging in boreholes are discussed. They include the application of neutron probes to porosity measurements, to lithological determinations based on macroscopic cross-section measurements and measurements of the concentration of chemical constituents in rocks and ores

Geological map of Uruguay scale 1,100,000. Agraciada Sheet R-23, Nueva Palmira Sheet R- 24

International Nuclear Information System (INIS)

Ferrando, L.; Eugui, W.; Cabrera, Z.; Elias, R.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Agraciada and Nueva Palmira) and the explanatory memoranda which describes the geological , lithological and sedimentological soil characteristics of: Fray Bentos, Camacho, Raygon, Libertad and Villa Soriano formations

Evidence of slumping/sliding in Krishna-Godavari offshore basin due to gas/fluid movements

Digital Repository Service at National Institute of Oceanography (India)

Ramprasad, T.; Dewangan, P.; Ramana, M.V.; Mazumdar, A.; Karisiddaiah, S.M.; Ramya, E.R.; Sriram, G.

lithology of mid-slope deposits is comprised of nannofossil-rich clay, nannofossil-bearing clay and foraminifera bearing clay. The HRS records and bathymetry reveal evidence of slumping and sliding of the upper and mid-slope sediments, which result in mass...

Agglutinated foraminifera from the shelf of east coast of India

Digital Repository Service at National Institute of Oceanography (India)

Almeida, F.; Setty, M.G.A.P.

belonging to six families, in a depth zone of 35-222 m of the east-coast of India (between Visakhapatnam and Masulipatnam along the continental shelf-slope region) in terms of lithology, faunal assemblage and their percentage distribution are discussed...

Mapping The Brightness Of The Ocean Bottoms

Energy Technology Data Exchange (ETDEWEB)

Milazzo, Damien Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-03-25

This is a presentation that describes some of the work LANL is doing in the way of; describing the lithology of the ocean floor; use of data to describe natural radioisotopes; and the determination of minerals that can be neutron activated.

Geological map of Uruguay Esc 1,100,000. Piriapolis Sheet G-29

International Nuclear Information System (INIS)

Preciozzi, F; Pena, S; Masquelin, E; Pias, J; Tabo, F

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Piriapolis) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils. Geomorphologically Piriapolis fotoplano is dominated by Las Animas and an important Cenozoic coverage

Overview of Hole GT3A: The sheeted dike/gabbro transition

Science.gov (United States)

Abe, N.; Harris, M.; Michibayashi, K.; de Obeso, J. C.; Kelemen, P. B.; Takazawa, E.; Teagle, D. A. H.; Coggon, J. A.; Matter, J. M.; Phase I Science Party, T. O. D. P.

2017-12-01

Hole GT3A (23.11409 N, 58.21172 E) was drilled by the Oman Drilling Project (OmDP) into Wadi Abdah of the Samail ophiolite, Oman. OmDP is an international collaboration supported by the International Continental Scientifi1c Drilling Program, the Deep Carbon Observatory, NSF, IODP, JAMSTEC, and the European, Japanese, German and Swiss Science Foundations, with in-kind support in Oman from the Ministry of Regional Municipalities and Water Resources, Public Authority of Mining, Sultan Qaboos University, and the German University of Technology. Hole GT3A was diamond cored in February to March 2017 to a total depth of 400 m. The outer surfaces of the cores were imaged and described on site before being curated, boxed and shipped to the IODP drill ship Chikyu, where they underwent comprehensive visual and instrumental analysis. Hole GT3A recovered predominantly sheeted dikes and gabbros and has been sub-divided into 4 igneous groups based on the abundance of gabbro downhole. Group 1 (Upper Sheeted Dike Sequence) occurs from 0 to 111.02 m, group II (Upper Gabbro Sequence) is from 111.02 to 127.89 m, group III (Lower Sheeted Dike Sequence) is between 127.89 to 233.84 m and group IV (Lower Gabbro Sequence) is from 233.84 to 400 m. Group II and IV are both associated with almost equal proportions of dikes to gabbroic lithologies, whereas group I & III have >95% dikes. The sheeted dikes were logged as either basalt (46.9 %) or diabase (26.2 %) depending on the predominant grain size of the dike. Gabbroic lithologies include (most to least abundant) gabbro, oxide gabbro and olivine gabbro. Other lithologies present include diorite (7.5%) and tonalite and trondhjemite (1%). Tonalite and trondhjemite are present as cm-sized dikelets and are found within group II and IV. Gabbroic lithologies generally display a varitextured appearance and are characterised by the co-existence of poikilitic and granular domains. Detailed observations of chilled margins and igneous contacts reveal

Hydrochemical and isotopic patterns in a calc-alkaline Cu- and Au-rich arid Andean basin: The Elqui River watershed, North Central Chile

International Nuclear Information System (INIS)

Oyarzún, Jorge; Carvajal, María José; Maturana, Hugo; Núñez, Jorge; Kretschmer, Nicole; Amezaga, Jaime M.; Rötting, Tobias S.; Strauch, Gerhard; Thyne, Geoffrey; Oyarzún, Ricardo

2013-01-01

Highlights: ► Major ions are provided by rock weathering and NaCl recycling. ► Aridity and cal-alkaline lithology effects abate acid drainage. ► Factors affecting hydrochemistry in mineral rich zone are addressed. ► Stable isotopes confirm the meteoric origin of groundwaters. ► High sulfate contents are explained by widespread sulfide minerals. - Abstract: The geochemistry of surface water and groundwater from the Elqui River basin, North-Central Chile, was studied in spring 2007 and fall 2008 to obtain a general understanding of the factors and mechanisms controlling the water chemistry of steep rivers located in mineral-rich, arid to semi arid zones. Besides its uniform intermediate igneous lithology, this basin is known for acid drainage and high As contents in the El Indio Au–Cu–As district, in its Andean head. Abundant tailings deposits are present in the middle part of the basin, where agricultural activities are important. According to the results, the chemical and isotopic composition of the Elqui basin surface water and groundwater is related to uniform calc-alkaline lithology and the major polluting system of the chemically reactive, but closed El Indio mining district. The resulting compositional imprints in surface and ground-water are, (a) high SO 4 levels, reaching about 1000 mg/L in the Toro River water, directly draining the mining area; (b) a major depletion of Fe and pollutant metals in surface water after the confluence of the Toro and La Laguna rivers; (c) similar chemical composition of surface and ground-waters that differ in H and O isotopic composition, reflecting the effect of differential evaporation processes downstream of the Puclaro dam; and (d) seasonal variations of Fe, Mn, Cu and Zn in surface water. In contrast, the groundwater chemistry exhibits moderate seasonal changes, mainly in HCO 3 - content. In spite of the acid drainage pollution, water quality is adequate for human consumption and irrigation. This is a

Slope stability probability classification, Waikato Coal Measures, New Zealand

Energy Technology Data Exchange (ETDEWEB)

Lindsay, P.; Gillard, G.R.; Moore, T.A. [CRL Energy, PO Box 29-415, Christchurch (New Zealand); Campbell, R.N.; Fergusson, D.A. [Solid Energy North, Private Bag 502, Huntly (New Zealand)

2001-01-01

Ferm classified lithological units have been identified and described in the Waikato Coal Measures in open pits in the Waikato coal region. These lithological units have been classified geotechnically by mechanical tests and discontinuity measurements. Using these measurements slope stability probability classifications (SSPC) have been quantified based on an adaptation of Hack's [Slope Stability Probability Classification, ITC Delft Publication, Enschede, Netherlands, vol. 43, 1998, 273 pp.] SSPC system, which places less influence on rock quality designation and unconfined compressive strength than previous slope/rock mass rating systems. The Hack weathering susceptibility rating has been modified by using chemical index of alteration values determined from XRF major element analyses. Slaking is an important parameter in slope stability in the Waikato Coal Measures lithologies and hence, a non-subjective method of assessing slaking in relation to the chemical index of alteration has been introduced. Another major component of this adapted SSPC system is the inclusion of rock moisture content effects on slope stability. The main modifications of Hack's SSPC system are the introduction of rock intact strength derived from the modified Mohr-Coulomb failure criterion, which has been adapted for varying moisture content, weathering state and confining pressure. It is suggested that the subjectivity in assessing intact rock strength within broad bands in the initial SSPC system is a major weakness of the initial system. Initial results indicate a close relationship between rock mass strength values, calculated from rock mass friction angles and rock mass cohesion values derived from two established rock mass classification methods (modified Hoek-Brown failure criteria and MRMR) and the adapted SSPC system. The advantage of the modified SSPC system is that slope stability probabilities based on discontinuity-independent and discontinuity-dependent data and a

Levels of potassium, uranium, thorium and rate of radiogenic heat production in the bedrock adjacent to Camamu and Almada sedimentary basins, Bahia, Brazil; Teores de potassio, uranio, torio e taxa de producao de calor radiogenico no embasamento adjacente as bacias sedimentares de Camamu e Almada, Bahia, Brasil

Energy Technology Data Exchange (ETDEWEB)

Sapucaia, Najara Santos; Barbosa, Johildo Salomao Figueiredo [Instituto de Geociencias, Universidade Federal da Bahia, Salvador, BA (Brazil); Argollo, Roberto Max de, E-mail: nss@cpgg.ufba.br, E-mail: johildo@cpgg.ufba.br, E-mail: robmax@ufba.br [Laboratorio de Fisica Nuclear Aplicada, Instituto de Fisica, Universidade Federal da Bahia, Salvador, BA (Brazil)

2005-10-15

The bedrock adjacent to Camamu and Almada sedimentary basins is characterized mainly by rocks of granulite and amphibolite facies, with archaean and paleoproterozoic ages, which belong to orogen Itabuna-Salvador-Curaca. The units in major proportion in this context are the metatonalites associated with basic and metamonzonites belonging to Itabuna belt. In smaller area occur the Teolandia granite and the Moenda granodiorite associated with the Ipiau band amphibolites, the charnockites and charnoenderbites of Jequie bloc, the neoproterozoic sienites and the mafic dikes. The K, U and Th contents of the rocks vary from 0,02 to 6,33% for K, from < 0,2 to 9,10 ppm for U and from < 0,4 to 64,38 ppm for Th. These contents are higher in the charnockites, Moenda granodiorite, Teolandia granite and sienites, intermediate in the metatonalites and metamonzonites and lower in the basic granulites. The heat production rates are higher in the lithologies where K, U and Th are also higher, varying from 0,58 to 5,57 {mu}W m{sup -3}. The coverage areas of such lithologies are, however, small compared with that of the metatonalitic granulites, metamonzonitic granulites and sienites where the rates vary from 0,10 to 1,44 {mu}W m{sup -3}, 0,23 to 5,55 {mu}W m{sup -3} and 0,60 to 2,24 {mu}W m{sup -3}, respectively. In this case, the heat production rates vary from 0,10 to 1,44 {mu}W m{sup -3}. The basic granulites have the smaller rates, from 0,06 to 0,36 {mu}W m-3. The observation of the lithologies in the margins of the two basins suggest that, in the bedrock under the younger sediments, may predominate the metatonalites, followed by the metamonzonites, with some significant participation of sienites in the Almada basin. In those lithologies, the volumetric heat production rates, with one standard deviation range, are 0,41 +- 0,30 {mu}W m{sup -3} for metatonalites, 0,71 +- 0,57 {mu}W m{sup -3} for metamonzonites and 1,20 +- 0,51 {mu}W m{sup -3} for sienites. (author)

Molybdenum, vanadium, and uranium weathering in small mountainous rivers and rivers draining high-standing islands

Science.gov (United States)

Gardner, Christopher B.; Carey, Anne E.; Lyons, W. Berry; Goldsmith, Steven T.; McAdams, Brandon C.; Trierweiler, Annette M.

2017-12-01

Rivers draining high standing islands (HSIs) and small mountainous rivers (SMRs) are known to have extremely high sediment fluxes, and can also have high chemical weathering yields, which makes them potentially important contributors to the global riverine elemental flux to the ocean. This work reports on the riverine concentrations, ocean flux, and weathering yields of Molybdenum (Mo), Vanadium (V), and Uranium (U) in a large number of small but geochemically important rivers using 338 river samples from ten lithologically-diverse regions. These redox-sensitive elements are used extensively to infer paleo-redox conditions in the ocean, and Mo and V are also important rock-derived micronutrients used by microorganisms in nitrogen fixation. Unlike in large river systems, in which dissolved Mo has been attributed predominately to pyrite dissolution, Mo concentrations in these rivers did not correlate with sulfate concentrations. V was found to correlate strongly with Si in terrains dominated by silicate rocks, but this trend was not observed in primarily sedimentary regions. Many rivers exhibited much higher V/Si ratios than larger rivers, and rivers draining young Quaternary volcanic rocks in Nicaragua had much higher dissolved V concentrations (mean = 1306 nM) than previously-studied rivers. U concentrations were generally well below the global average with the exception of rivers draining primarily sedimentary lithologies containing carbonates and shales. Fluxes of U and Mo from igneous terrains of intermediate composition are lower than the global average, while fluxes of V from these regions are higher, and up to two orders of magnitude higher in the Nicaragua rivers. Weathering yields of Mo and V in most regions are above the global mean, despite lower than average concentrations measured in some of those systems, indicating that the chemical weathering of these elements are higher in these SMR watersheds than larger drainages. In regions of active boundaries

Structural control on the emplacement of contemporaneous Sn-Ta-Nb mineralized LCT pegmatites and Sn bearing quartz veins: Insights from the Musha and Ntunga deposits of the Karagwe-Ankole Belt, Rwanda

Science.gov (United States)

Hulsbosch, Niels; Van Daele, Johanna; Reinders, Nathan; Dewaele, Stijn; Jacques, Dominique; Muchez, Philippe

2017-10-01

The Nb-Ta-Sn pegmatites and Sn quartz veins of the Rwamagana-Musha-Ntunga area in eastern Rwanda are part of the Mesoproterozoic Karagwe-Ankole Belt. These commodities are on a regional scale spatiotemporally associated to the early Neoproterozoic fertile G4-granite generation. Although a transition from the lithium-cesium-tantalum pegmatites to cassiterite-microcline-quartz veins has been observed in the Rwamagana-Musha-Ntunga area, the structural control and the paragenetic relationship between the mineralized pegmatites and the Sn bearing quartz veins is largely unknown. Consequently, this study investigates the occurrence of pegmatites and quartz veins and the structural and lithological controls on their emplacement. The metasediments in the area are affected by a regional compressional regime with a shortening direction oriented N70E, which resulted in a N20W-oriented fold sequence. The Lake Muhazi granite is present in center of the Karehe anticline. The structural orientations of pegmatites and quartz veins show that two important factors control their emplacement. The first control is the reactivation of pre-existing discontinuities such as the bedding, bedding-parallel joints or strike-slip fault planes. In view of the regional structural grain in the Rwamagana-Musha-Ntunga area, this corresponds with abundant N20W-oriented pegmatites and quartz veins. The reactivation is strongly related to the lithology of the host rocks. The Musha Formation, which mainly consists of decimeter- to meter-scale lithological alternations of metapelite, metasiltstone and metasandstone, represents the most suitable environment for bedding reactivation. This is reflected in the predominance of bedding-parallel pegmatites and quartz veins hosted by the Musha Formation. Strike-parallel joints were mainly observed in the competent lithologies. The second controlling factor is related to the regional post-compressional stress regime. New joints initiated upon emplacement of the

Mechanical-Stratigraphic Characterization of the Eagle Ford Formation in Outcrop and Core, McMullen and Terrell Counties, Texas

Science.gov (United States)

Xu, G.; Chester, J. S.; Chester, F. M.

2017-12-01

The objective of this project is to characterize the geomechanical properties of individual and composite lithologic units over length scales of decimeter to tens of meters. We have characterized the stratigraphy and lithology of the Eagle Ford Formation in outcrops at Lozier and Antonio Canyons of West TX, and in core taken at 3.2 km depth in McMullen County, TX. Dominant lithologies examined include reworked ash layers, argillaceous mudstone, organic-rich mudstone, foraminifera wackestone, packstone, pyritic packstone, and foraminifera/dolomitic packstone-grainstone. Samples of these units are deformed in triaxial compression at 1- 40 MPa confining pressure (Pc), and room temperature and humidity. The elastic properties, pre-fracture yielding (ductility), and fracture strength are primarily a function of particle size, texture (degree of mud versus grain support), and composition. Young's Modulus (YM) and Poison's Ratio (PR) increase similarly with an increase in grain-support and carbonate content, and a decrease in organic matter and clay. The greatest change occurs at the transition from mud-supported to grain-supported textures where YM and PR increase by a factor of 3 and 1.5, respectively. Both YM and PR can display anisotropy with directional variation of 30%, most notably in micro-laminated units, but also in the more massive pyritic packstones. Overall, pre-fracture ductility decreases with an increase in carbonate content; ductile strain in the argillaceous- and organic-rich-mudstones is 1.4%, 3-4 times greater than that in the packstone/grainstone. Fracture strength increases with an increase in carbonate content and a decrease in clay content. The organic rich mudstone fails at 130 MPa, is nearly 2 times stronger than argillaceous mudstones, and 50% weaker than packstone/grainstones at 1 MPa Pc. The angle of internal friction is 45 degrees for all lithologies, consistent with a transition in fracture from opening- to shear-mode between 1 to 15 MPa Pc

Some variations in petrography of South African Karoo dolerites and the effects thereof on aggregate properties

CSIR Research Space (South Africa)

Leyland, R

2014-01-01

Full Text Available Supergroup, which is generally lacking in quality aggregate lithologies. The Karoo Dolerite Suite can however, despite being a single geological unit, be of significantly variable petrography mainly due to the very large area (>500,000 km2) and wide variety...

Upper Campanian−Maastrichtian holostratigraphy of the eastern Danish Basin

DEFF Research Database (Denmark)

Surlyk, Finn; Rasmussen, Susanne Lil; Boussaha, Myriam

2013-01-01

of changes in chalk facies, water depths and sea-water temperatures. Combined lithological data, a suite of petrophysical logs including gamma ray (GR) logs, nannofossil and dinoflagellate palaeontology, stable carbon isotopes, seismic reflection and refraction sections form the basis for the definition...

AUTHOR INDEX

Indian Academy of Sciences (India)

Magnetic anomalies of offshore Krishna–Godavari basin, eastern continental margin of India. 405. Tewari Ram Chandra. Application of Markov chain and entropy analysis to lithologic succession – an example from the early. Permian Barakar Formation, Bellampalli coalfield,. Andhra Pradesh, India. 583. Thakur Alpana.

Do landslides follow landslides? Insights in path dependency from a multi-temporal landslide inventory

NARCIS (Netherlands)

Samia, Jalal; Temme, Arnaud; Bregt, Arnold; Wallinga, Jakob; Guzzetti, Fausto; Ardizzone, Francesca; Rossi, Mauro

2017-01-01

Landslides are a major category of natural disasters, causing loss of lives, livelihoods and property. The critical roles played by triggering (such as extreme rainfall and earthquakes), and intrinsic factors (such as slope steepness, soil properties and lithology) have previously successfully

Probability estimate of confirmability of the value of predicted oil and gas reserves of the Chechen-Ingushetiya. Veroyatnostnaya otsenka podtverzhdaemosti velichiny prognoznykh zapasov nefti is gaza Checheno-Ingushetii

Energy Technology Data Exchange (ETDEWEB)

Merkulov, N.E.; Lysenkov, P.P.

1981-01-01

Estimated are the reliable predicted reserves of oil and gas of the Chechen-Ingushetia by methods of probability calculations. Calculations were made separately for each oil-bearing lithologic-stratigraphic horizon. The computation results are summarized in a table, and graphs are constructed.

Rare Earth Element Geochemistry And Protoliths Of Schists In ...

African Journals Online (AJOL)

The Nigerian schist belts constitute the most important lithologic units necessary for the unravelling of the geochemical and geodynamic evolution of the basement complex. The schists have however undergone extensive alterations owing to weathering and metamorphism. REE abundance and distribution patterns of ...

New petrographic, geochemical and geochronological data for the Reguengos de Monsaraz pluton (Ossa Morena Zone, SW Iberian Massif, Portugal)

Energy Technology Data Exchange (ETDEWEB)

Antunes, A.; Santos, J. F.; Azevedo, M. R.; Mendez, M. H.; Ribeiro, S.

2010-07-01

The Reguengos de Monsaraz pluton is a late to post-tectonic Variscan intrusion occurring in the Ossa Morena Zone (Iberian Variscan Chain). The dominant lithological types are tonalites and granodiorites, but the internal area of the massif is composed of gabbro-dioritic rocks. Field evidence shows that the intrusion is heterogeneous at mesoscopic scale suggesting that the emplacement of mafic and felsic magmas was contemporaneous. Petrographic and geochemical studies reveal that the different lithologic types define a continuous sequence with compositions varying from metaluminous to slightly peraluminous and a typical calc-alkaline signature. In Harker variation diagrams, it is possible to observe systematic rectilinear correlations pointing to the involvement of magma mingling/mixing processes in the petrogenesis of this sequence. Rb-Sr isotopic data, using a mineral-mineral pair from a granodiorite sample, yielded an age of 298 Ma, interpreted as a cooling age after igneous crystallization. (Author) 13 refs.

Petrophysical Analysis of Siliceous Ooze Sediments, Ormen Lange Field, Norway

DEFF Research Database (Denmark)

Awedalkarim, Ahmed; Fabricius, Ida Lykke

, but apparent porosity indications in any other lithology, such as siliceous ooze, are wrong and they should be corrected. The apparent bulk density log should be influenced by the hydrogen in opal as also the neutron porosity tools because they are sensitive to the amount of hydrogen in a formation...... present in the solid. Some minerals of siliceous ooze, such as opal, have hydrogen in their structures which influences the measured hydrogen index (HI). The neutron tool obtains the combined signal of the HI of the solid phase and of the water that occupies the true porosity. The HI is equal to true...... to interpret lithology and the unusual physical properties of the studied intervals. The integration of all these data revealed that the studied siliceous ooze is a mixture of opal and non-opal (shale). Our results proved to be reasonably consistent. The studied intervals apparently do not contain hydrocarbons....

A Multi-Decadal Sample Return Campaign Will Advance Lunar and Solar System Science and Exploration by 2050

Science.gov (United States)

Neal, C. R.; Lawrence, S. J.

2017-01-01

There have been 11 missions to the Moon this century, 10 of which have been orbital, from 5 different space agencies. China became the third country to successfully soft-land on the Moon in 2013, and the second to successfully remotely operate a rover on the lunar surface. We now have significant global datasets that, coupled with the 1990s Clementine and Lunar Prospector missions, show that the sample collection is not representative of the lithologies present on the Moon. The M3 data from the Indian Chandrayaan-1 mission have identified lithologies that are not present/under-represented in the sample collection. LRO datasets show that volcanism could be as young as 100 Ma and that significant felsic complexes exist within the lunar crust. A multi-decadal sample return campaign is the next logical step in advancing our understanding of lunar origin and evolution and Solar System processes.

REGIONAL GEOLGICAL MAPPING IN TROPICAL ENVIRONMENTS USING LANDSAT TM AND SRTM REMOTE SENSING DATA

Directory of Open Access Journals (Sweden)

A. Beiranvand Pour

2015-10-01

Full Text Available Landsat Thematic Mapper (TM and Shuttle Radar Topography Mission (SRTM data were used to produce geological maps in tropical environments. Lineament, lithology and landform maps were produced for all states in peninsular Malaysia in this study. Kedah, Perak and Terengganu states have been selected as case studies to demonstrate the results of the data and techniques used. Directional filtering technique was applied to Landsat TM bands 4, 5 and 3 for lineament mapping. The lithology map was produced using Landsat TM bands combination consist of bands 4, 3 and 2. Digital elevation model and landform map were produced using SRTM data in 3 Dimension (3D and 2 Dimension (2D perspective views, respectively. The produced geological maps and the remote sensing data and methods applied in this study are mostly appropriate for hazard risk mapping applications and mineral exploration projects in the peninsular Malaysia and tropical environments.

Mapping the lithotypes using the in-situ measurement of time domain induced polarization: El-log

DEFF Research Database (Denmark)

Auken, Esben; Fiandaca, Gianluca; Christiansen, Anders Vest

This study presents a novel application of the El-log-drilling technique for measurement while drilling of the DC, time domain IP and gamma log. In addition pore water samples can be taken at arbitrary levels. The technique itself is developed in Denmark and has been widely used in the field...... of ground water and environmental studies. The El-log drilling method yields detailed information on small changes in lithology, sediment chemistry and water quality and with data comparable to what can be obtained in the laboratory. . We collected the data at a landfill site located near Grindsted...... in the southern part of Denmark. The purpose of the study was 1) to obtain a direct correlation between the undisturbed geophysical logs and surface measurements, 2) correlation of IP parameters to lithology and grain size distribution and 3) to investigate any correlation with effluent and IP parameters. We...

Geology and geochronology of the Sub-Antarctic Snares Islands/Tini Heke, New Zealand

DEFF Research Database (Denmark)

Scott, JM; Turnbull, IM; Sagar, MW

2015-01-01

are prismatic and yield an essentially unimodal age population of c. 116 Ma that is within error of the granodiorite. These properties suggest that the dated raft represents a meta-igneous rock despite its mica-rich nature. Some schistose rocks on the Western Chain contain coarse relict plagioclase phenocrysts...... and appear to have an igneous protolith. No conclusive metasedimentary rocks have been identified, although sillimanite-bearing mica-rich schist occurs on Rua. Deformation of the crystalline rocks occurred after Snares Granite intrusion and before cooling below muscovite K–Ar closure at 400 ± 50 °C at 95 Ma......The first comprehensive geological map, a summary of lithologies and new radiogenic isotope data (U–Pb, Rb–Sr) are presented for crystalline rocks of the Sub-Antarctic Snares Islands/Tini Heke, 150 km south of Stewart Island. The main lithology is Snares Granite (c. 109 Ma from U–Pb dating...

An integrtated approach to the use of Landsat TM data for gold exploration in west central Nevada

Science.gov (United States)

Mouat, D. A.; Myers, J. S.; Miller, N. L.

1987-01-01

This paper represents an integration of several Landsat TM image processing techniques with other data to discriminate the lithologies and associated areas of hydrothermal alteration in the vicinity of the Paradise Peak gold mine in west central Nevada. A microprocessor-based image processing system and an IDIMS system were used to analyze data from a 512 X 512 window of a Landsat-5 TM scene collected on June 30, 1984. Image processing techniques included simple band composites, band ratio composites, principal components composites, and baseline-based composites. These techniques were chosen based on their ability to discriminate the spectral characteristics of the products of hydrothermal alteration as well as of the associated regional lithologies. The simple band composite, ratio composite, two principal components composites, and the baseline-based composites separately can define the principal areas of alteration. Combined, they provide a very powerful exploration tool.

Remote sensing applied to copper and uranium exploration

International Nuclear Information System (INIS)

Abrams, M.; Conel, J.

1982-01-01

A summary of some of the results of the Joint NASA/Geosat Test Case copper and uranium projects is presented. Two uranium deposits in Wyoming and Utah were investigated. These sites represented a Colorado Plateau sedimentary uranium deposit, and a deposit in fractured and crushed Precambrian granite. Each of the remote sensing data sets analyzed provided some important geologic information applicable to porphyry copper and uranium exploration. Landsat and Seasat data were best suited for regional reconnaissance of structural patterns, and some lithologic/alteration mapping. The higher spatial and spectral resolution provided by the aircraft scanners allowed improved separation of geologic units and delineation of more detailed fault patterns. Overall, th TMS provided the most useful data for lithologic and alteration mapping. The presence of the wavelength band in the 2.2 μm region was found to be invaluable for identifying areas with hydrous mineral-bearing rocks

Parameters controlling fracturing distribution: example of an Upper Jurassic marly-calcareous formation (eastern Paris Basin)

International Nuclear Information System (INIS)

Andre, G.; Rebours, H.; Wileveau, Y.; Proudhon, B.

2006-01-01

Study of fractures along a 490-m vertical section of marl/limestone alternations in the Upper Jurassic (Meuse/Haute-Marne underground research laboratory-eastern Paris Basin) reveals their organization and the different states of palaeo-stress. Type and extension of tectonic structures seem to be controlled principally by lithology and secondary by depth. Also, it appears deviations of Alpine palaeo-stresses between Kimmeridgian and Oxfordian formations. These deviations are related to the presence of marl/limestone contacts. The vertical evolution of current horizontal maximum stress shows a similar behaviour, with deviations at the walls of Callovo-Oxfordian argilites. These results allow us to point out and to discuss the impact of lithology, rheology and depth on fracturing occurrence and distribution. Furthermore, this study suggests the role of Callovo-Oxfordian as a barrier for fracture development between the limestones of Dogger and Oxfordian formations. (authors)

Parameters controlling fracturing distribution: example of an Upper Jurassic marly-calcareous formation (eastern Paris Basin); Parametres controlant la distribution de la fracturation: exemple dans une serie marno-calcaire du Jurassique superieur (Est du bassin de Paris)

Energy Technology Data Exchange (ETDEWEB)

Andre, G.; Rebours, H.; Wileveau, Y. [Agence Nationale pour la Gestion des Dechets Radioactifs (ANDRA), Laboratoire de recherche souterrain de Meuse/Haute-Marne, 55 - Bure (France); Proudhon, B. [GEO.TER, 34 - Clapiers (France)

2006-10-15

Study of fractures along a 490-m vertical section of marl/limestone alternations in the Upper Jurassic (Meuse/Haute-Marne underground research laboratory-eastern Paris Basin) reveals their organization and the different states of palaeo-stress. Type and extension of tectonic structures seem to be controlled principally by lithology and secondary by depth. Also, it appears deviations of Alpine palaeo-stresses between Kimmeridgian and Oxfordian formations. These deviations are related to the presence of marl/limestone contacts. The vertical evolution of current horizontal maximum stress shows a similar behaviour, with deviations at the walls of Callovo-Oxfordian argilites. These results allow us to point out and to discuss the impact of lithology, rheology and depth on fracturing occurrence and distribution. Furthermore, this study suggests the role of Callovo-Oxfordian as a barrier for fracture development between the limestones of Dogger and Oxfordian formations. (authors)

Formation evaluation of fractured basement, Cambay Basin, India

International Nuclear Information System (INIS)

Gupta, Saurabh Datta; Farooqui, M Y; Chatterjee, Rima

2012-01-01

Unconventional reservoirs such as fractured basalts, shale gas and tight sand are currently playing an important role in producing a significant amount of hydrocarbon. The Deccan Trap basaltic rocks form the basement of the Cambay Basin, India, and hold commercially producible hydrocarbon. In this study two wells drilled through fractured basalts are chosen for evaluating the lithology, porosity and oil saturation of the reservoir sections. Well logs, such as gamma ray, high resolution resistivity, litho density, compensated neutron and elemental capture spectroscopy, have been used in cross-plotting techniques for lithology and mineral identification. Formation micro imagery log data have been analysed to quantify the fractures and porosity in the fractured reservoirs for a well in the south Ahmedabad block of the Cambay Basin. The results of the analysis of two wells are presented and discussed and they are found to be in good agreement with geological and production data. (paper)

The Main Features of the Geological Modeling Process of a Shallow Deposit of Super-Viscous Oil in Aspect of Development Strategy Planning with the Use of Steam‑Assisted Gravity Drainage Method

Directory of Open Access Journals (Sweden)

S.P. Novikova

2017-11-01

Full Text Available Deficiency of minerals, limited reserves of conventional hydrocarbon raw materials indicates the need to involve in the fuel and energy complex of other sources of hydrocarbons. Fields of super-viscous oil are one of the sources. This article is devoted to the study of sediments of the Permian sedimentary complex containing super-viscous oil deposits. The geological structure of the Lower Kazanian and Ufimian deposits is considered. A characteristic of the Sheshmian sandstone pack is given. The analysis of the set of geophysical studies is presented. Modeling of a shallow super-viscous oil deposit based on the lithologic-technological types of the productive formation was carried out, based on the results of drilling, core material and logging. The features of constructing the structural framework of a three-dimensional grid, and a lithological-technological model are highlighted. The distribution of porosity, permeability and oil saturation is described.

Groundwater flow and tritium migration from the SRS Old Burial Ground to Fourmile Branch

International Nuclear Information System (INIS)

Flach, G.P.; Hamm, L.L.; Harris, M.K.

1996-04-01

The objectives of this investigation are twofold. The initial goal is to devise and demonstrate a technique for directly incorporating fine-scale lithologic data into heterogeneous hydraulic conductivity fields, for improved groundwater flow and contaminant transport model accuracy. The ultimate goal is to rigorously simulate past and future tritium migration from the SRS Old Burial Ground towards Fourmile Branch, to better understand the effects of various remediation alternatives such as no action and capping. Large-scale variability in hydraulic conductivity is usually the main influence on field-scale groundwater flow patterns and dispersive transport, following the relative locations of recharge and discharge areas. Incorporating realistic hydraulic conductivity heterogeneity into flow and transport models is paramount to accurate simulations, particularly for contaminant migration. Sediment lithologic descriptions and geophysical logs typically offer finer spatial resolution, and therefore more potential information about heterogeneity, than other site characterization data

Use of induced polarization to characterize the hydrogeologic framework of the zone of surface‐water/groundwater exchange at the Hanford 300 Area, WA

Science.gov (United States)

Slater, Lee; Ntarlagiannis, Dimitrios; Day-Lewis, Frederick D.; Mwakanyamale, Kisa; Lane, John W.; Ward, Andy; Versteeg, Roelof J.

2010-01-01

An extensive continuous waterborne electrical imaging (CWEI) survey was conducted along the Columbia River corridor adjacent to the U.S. Department of Energy (DOE) Hanford 300 Area, WA, in order to improve the conceptual model for exchange between surface water and U‐contaminated groundwater. The primary objective was to determine spatial variability in the depth to the Hanford‐Ringold (H‐R) contact, an important lithologic boundary that limits vertical transport of groundwater along the river corridor. Resistivity and induced polarization (IP) measurements were performed along six survey lines parallel to the shore (each greater than 2.5 km in length), with a measurement recorded every 0.5–3.0 m depending on survey speed, resulting in approximately 65,000 measurements. The H‐R contact was clearly resolved in images of the normalized chargeability along the river corridor due to the large contrast in surface area (hence polarizability) of the granular material between the two lithologic units. Cross sections of the lithologic structure along the river corridor reveal a large variation in the thickness of the overlying Hanford unit (the aquifer through which contaminated groundwater discharges to the river) and clearly identify locations along the river corridor where the underlying Ringold unit is exposed to the riverbed. Knowing the distribution of the Hanford and Ringold units along the river corridor substantially improves the conceptual model for the hydrogeologic framework regulating U exchange between groundwater and Columbia River water relative to current models based on projections of data from boreholes on land into the river.

Investigating Potential Artesian Aquifers in Rod-Kohi Area of DI Khan, NWFP using GIS and Geo-Processing Techniques

Directory of Open Access Journals (Sweden)

Arshad Ashraf

2012-07-01

Full Text Available The artesian aquifers provide economical and sustainable source of groundwater for irrigation and domestic use. GIS (Geographic Information System was used for development and integration of spatial databases, analysis and visualization of spatial data in two- and three-dimensional views. The aquifer system of Daraban Rod-Kohi area of DI Khan was analyzed to identify potential artesian aquifers using geological sections of the observation wells representing detail of subsurface lithology and strata encountered. According to an estimate, about 1,700 million m3 of extractable volume of groundwater exists in this part of rod-kohi area. Different profile sections were drawn to analyze the subsurface condition of the study area using Rockworks GIS-based software. The geo-processing technique of horizontal litho-blending was utilized for lithological modeling. Based on stratigraphic information of the area, three distinct aquifers were identified down to a depth of about 200 meters among which two are semi-confined to confined having prospects of artesian water. The 2D and 3D analysis show that characteristics of the confined aquifers vary spatially with the subsurface lithology and structural setup of the area. The depth range of confined layer-1 is found between 118 and 133 meters while of confined layer-2 between 182 and 195 meters. The output data indicated a close agreement with the observed data of the artesian wells. The study results can provide base for detail investigation of artesian resource and selection of potential sites for installation of artesian wells in the target area.

Remote sensing detection of gold related alteration zones in Um Rus area, Central Eastern Desert of Egypt

Science.gov (United States)

Amer, Reda; Kusky, Timothy; El Mezayen, Ahmed

2012-01-01

Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Phased Array L-band Synthetic Aperture Radar (PALSAR) images covering the Um Rus area in the Central Eastern Desert of Egypt were evaluated for mapping geologic structure, lithology, and gold-related alteration zones. The study area is covered by Pan-African basement rocks including gabbro and granodiorite intruded into a variable mixture of metavolcanics and metasediments. The first three principal component analyses (PCA1, PCA2, PCA3) in a Red-Green-Blue (RGB) of the visible through shortwave-infrared (VNIR + SWIR) ASTER bands enabled the discrimination between lithological units. The results show that ASTER band ratios ((2 + 4)/3, (5 + 7)/6, (7 + 9)/8) in RGB identifies the lithological units and discriminates the granodiorite very well from the adjacent rock units.The granodiorites are dissected by gold-bearing quartz veins surrounded by alteration zones. The microscopic examination of samples collected from the alteration zones shows sericitic and argillic alteration zones. The Spectral Angle Mapper (SAM) and Spectral Information Divergence (SID) supervised classification methods were applied using the reference spectra of the USGS spectral library. The results show that these classification methods are capable of mapping the alteration zones as indicated by field verification work. The PALSAR image was enhanced for fracture mapping using the second moment co-occurrence filter. Overlying extracted faults and alteration zone classification images show that the N30E and N-S fractures represent potential zones for gold exploration. It is concluded that the proposed methods can be used as a powerful tool for ore deposit exploration.

Pen Branch fault: Confirmatory drilling results

International Nuclear Information System (INIS)

Stieve, A.; Coruh, C.; Costain, J.K.

1994-01-01

The Confirmatory Drilling Project is the final investigation under the Pen Branch Fault Program initiated to determine the capability of the Pen Branch fault (PBF) to release seismic energy. This investigation focused on a small zone over the fault where previously collected seismic reflection data had indicated the fault deforms the subsurface at 150 msec (with reference to an 80 m reference datum). Eighteen drill holes, 2 to basement and the others to 300 ft, were arranged in a scatter pattern over the fault. To adequately define configuration of the layers deformed by the fault boreholes were spaced over a zone of 800 ft, north to south. The closely spaced data were to confirm or refute the existence of flat lying reflectors observed in seismic reflection data and to enable the authors to identify and correlate lithologic layers with seismic reflection data. Results suggest that deformation by the fault in sediments 300 ft deep ad shallower is subtle. Corroboration of the geologic interpretation with the seismic reflection profile is ongoing but preliminary results indicate that specific reflectors can be assigned to lithologic layers. A large amplitude package of reflections below a flat lying continuous reflection at 40 msec can be correlated with a lithology that corresponds to carbonate sediments in geologic cross-section. Further, data also show that a geologic layer as shallow as 30 ft can be traced on these seismic data over the same subsurface distance where geologic cross-section shows corresponding continuity. The subsurface structure is thus corroborated by both methods at this study site

MRF-based Stochastic Joint Inversion of Hydrological and Geophysical Datasets to Evaluate Aquifer Heterogeneities.

Science.gov (United States)

Oware, E. K.

2016-12-01

Hydrogeophysical assessment of aquifer parameters typically involve sparse noisy measurements coupled with incomplete understanding of the underlying physical process. Thus, recovering a single deterministic solution in light of the largely uncertain inputs is unrealistic. Stochastic imaging (SI) allows the retrieval of multiple equiprobable outcomes that facilitate probabilistic assessment of aquifer properties in a realistic fashion. Representation of prior models is a key aspect of the formulation of SI frameworks. However, higher-order (HO) statistics for representing complex priors in SI are usually borrowed from training images (TIs), which may bias outcomes if the prior hypotheses are inaccurate. A data-driven HO simulation alternative based on Markov random field (MRF) modeling is presented. Here, the modeling of spatial features is guided by potential (Gibbs) energy (PE) minimization. The estimation of the PE encompasses local neighborhood configuration (LNC) and prior statistical constraints. The lower the estimated PE the higher the likelihood of that particular local structure and vice versa. Hence, the LNC component of the PE estimation is designed to promote the recovery of some desired structures while penalizing the retrieval of patterns that are inconsistent with prior expectation. The statistical structure is adaptively inferred from the joint conditional datasets. The reconstruction proceeds in two-steps with the estimation of the lithological structure of the aquifer followed by the simulation of attributes within the identified lithologies. This two-step approach permits the delineation of physically realistic crisp lithological boundaries. The algorithm is demonstrated with a joint inversion of time-lapse concentration and electrical resistivity measurements, in a hypothetical trinary hydrofacies aquifer characterization problem.

Three-dimensional geologic model of the southeastern Espanola Basin, Santa Fe County, New Mexico

Science.gov (United States)

Pantea, Michael P.; Hudson, Mark R.; Grauch, V.J.S.; Minor, Scott A.

2011-01-01

This multimedia model and report show and describe digital three-dimensional faulted surfaces and volumes of lithologic units that confine and constrain the basin-fill aquifers within the Espanola Basin of north-central New Mexico. These aquifers are the primary groundwater resource for the cities of Santa Fe and Espanola, six Pueblo nations, and the surrounding areas. The model presented in this report is a synthesis of geologic information that includes (1) aeromagnetic and gravity data and seismic cross sections; (2) lithologic descriptions, interpretations, and geophysical logs from selected drill holes; (3) geologic maps, geologic cross sections, and interpretations; and (4) mapped faults and interpreted faults from geophysical data. Modeled faults individually or collectively affect the continuity of the rocks that contain the basin aquifers; they also help define the form of this rift basin. Structure, trend, and dip data not previously published were added; these structures are derived from interpretations of geophysical information and recent field observations. Where possible, data were compared and validated and reflect the complex relations of structures in this part of the Rio Grande rift. This interactive geologic framework model can be used as a tool to visually explore and study geologic structures within the Espanola Basin, to show the connectivity of geologic units of high and low permeability between and across faults, and to show approximate dips of the lithologic units. The viewing software can be used to display other data and information, such as drill-hole data, within this geologic framework model in three-dimensional space.

New safety performance indicators for safety assessment of radioactive waste disposal facilities. Cuban experience

International Nuclear Information System (INIS)

Peralta Vital, J.L.; Castillo, R.G.; Olivera, J.

2002-01-01

The paper shows the Cuban experience on implementing geological disposal of radioactive waste and the necessity for identifying new safety performance indicators for the safety assessment (SA) of radioactive waste disposal facilities. The selected indicator was the concentration of natural radioactive elements (U, Ra, Th, K) in the Cuban geologic environment. We have carried out a group of investigations, which have allowed characterising the concentration for the whole Country, creating a wide database where this indicator is associated with the lithology. The main lithologies in Cuba are: the sedimentary rocks (70 percent of national occurrence), which are present in the three regions (limestone and lutite), and finally the igneous and metamorphic rocks. The results show the concentrations ranges of the natural radionuclides associated fundamentally to the variation in the lithology and geographical area of the Country. In Cuba, the higher concentration (ppm) of Uranium and Radium are referenced to the Central region associated to Skarn, while for Thorium (ppm) and Potassium (%), in the East region the concentration peaks in Tuffs have been found. The concentrations ranges obtained are preliminary, they characterise the behaviour of this parameter for the Cuban geology, but they do not represent limits for safety assessment purposes yet. Also other factors should be taken into account as the assessment context, time scales and others assumptions before establishing the final concentration limits for the natural radionuclides as a radiological and nuclear safety performance indicator complementary to dose and risk for safety assessment for radiological and nuclear facilities. (author)

Regional geology mapping using satellite-based remote sensing approach in Northern Victoria Land, Antarctica

Science.gov (United States)

Pour, Amin Beiranvand; Park, Yongcheol; Park, Tae-Yoon S.; Hong, Jong Kuk; Hashim, Mazlan; Woo, Jusun; Ayoobi, Iman

2018-06-01

Satellite remote sensing imagery is especially useful for geological investigations in Antarctica because of its remoteness and extreme environmental conditions that constrain direct geological survey. The highest percentage of exposed rocks and soils in Antarctica occurs in Northern Victoria Land (NVL). Exposed Rocks in NVL were part of the paleo-Pacific margin of East Gondwana during the Paleozoic time. This investigation provides a satellite-based remote sensing approach for regional geological mapping in the NVL, Antarctica. Landsat-8 and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) datasets were used to extract lithological-structural and mineralogical information. Several spectral-band ratio indices were developed using Landsat-8 and ASTER bands and proposed for Antarctic environments to map spectral signatures of snow/ice, iron oxide/hydroxide minerals, Al-OH-bearing and Fe, Mg-OH and CO3 mineral zones, and quartz-rich felsic and mafic-to-ultramafic lithological units. The spectral-band ratio indices were tested and implemented to Level 1 terrain-corrected (L1T) products of Landsat-8 and ASTER datasets covering the NVL. The surface distribution of the mineral assemblages was mapped using the spectral-band ratio indices and verified by geological expeditions and laboratory analysis. Resultant image maps derived from spectral-band ratio indices that developed in this study are fairly accurate and correspond well with existing geological maps of the NVL. The spectral-band ratio indices developed in this study are especially useful for geological investigations in inaccessible locations and poorly exposed lithological units in Antarctica environments.

Microfacies and Diagenetic Fabric of the Lockhart Limestone, Kotal Pass Section, Northeast of Kohat, Pakistan

Directory of Open Access Journals (Sweden)

Muhammad Waseem Khan

2016-06-01

Full Text Available The present study is intended to describe the carbonate microfacies of the Paleocene Lockhart Limestone in area northeast of the Kohat City. The analyzed limestone in the area is 65m thick and predominantly medium to thick bedded, nodular to brecciated and richly fossiliferous. Thin interbeds of marl are observed in the main lithological unit. The lower contact of the Lockhart Limestone is faulted with the Samana Suk Formation of the Jurassic age while conformably overlain by the Patala Formation of Paleocene to Eocene age. The major lithological unit is comprised of predominant assemblage of larger benthic and smaller planktonic foraminifers with accretion of ostracods, dasycladacean algae, echinoderms, gastropods and corals. On the basis of field and laboratory observations, two distinct types of microfacies have been identified as i Dasyclad-Miliolid Foram Wacke-Packstone microfacies of the inner shelf, sub tidal lagoon, ii Larger Foram Packstone microfacies of the middle shelf. The Limestone represents a carbonate cyclic sequence marked by three, transgressive, deepening up cycles representing a gradual sea level rise compensated by vertical accumulation of microfacies. The commencement of each cycle is clearly marked by the input of land-derived siliciclastic sediments and near shore restricted marine faunal/floral assemblage in the inner shelf microfacies gradually thinning up section where the microfacies become deeper offshore. The diagenetic modifications are observed in the shape of compactional framework, dolomitization, aragonite to calcite alteration and spar filled fractures in the main lithological unit of the Lockhart Limestone.

Geological characterization of contaminated sites near the city of Horsens, Denmark

DEFF Research Database (Denmark)

Andersen, Theis Raaschou; Poulsen, Søren Erbs; Thomsen, Peter

characterization of three contaminated sites situated in urban and semi-urban areas around the city of Horsens in corporation with authorities. The existing data from the three field sites include lithological profiles from boreholes. In order to increase the data density, Electrical Resistivity Tomography (ERT...

10 CFR 960.3-1-4-2 - Site nomination for characterization.

Science.gov (United States)

2010-01-01

... SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-2 Site nomination for... site, including lithologic logging and hydrologic and geophysical testing of such boreholes, laboratory testing of core samples for the evaluation of geochemical and engineering rock properties, and chemical...

Geological map of Uruguay Esc 1,100,000. Bequelo Sheet N0-20

International Nuclear Information System (INIS)

Montana, J.; Ford, I.; Morales, H.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Bequelo) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics of the precambrian period in the Bequelo stream as well as the Mercedes , Asencio and Fray Bentos formations

Geological map of Uruguay Esc 1,100,000. Talita Sheet J-24

International Nuclear Information System (INIS)

Campal, N; Chulepin, H

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Talita) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils.The area belongs to the Rio de la Plata socket basin is associated with the orogenic cycle

Benthic macrofauna variations and community structure in Cenomanian cyclic chalk-marl from Southerham Grey Pit, SE England

DEFF Research Database (Denmark)

Lauridsen, Bodil Wesenberg; Gale, A. S.; Surlyk, Finn

2009-01-01

Cenomanian chalk-marl couplets from England represent the 20 ka Milankovitch precession cycle. Fossil communities from both chalk and marl are identified to test if the orbital fluctuations and the associated changes in substrate lithology and climate exerted any control on the benthic macrofauna...

Geological map of Uruguay Esc 1,100,000. Molles Sheet K-19

International Nuclear Information System (INIS)

Ford, I

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Molles) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils belong to the Cretaceous, Tertiary and Quaternary period in Arapey, Mercedes, Asencio, Palmitas, Fray Bentos and Libertad formations

Palynostratigraphy of Permian succession from Binja Block, South ...

Indian Academy of Sciences (India)

Palynological investigations are carried out on approximately 538.00-m thick Gondwana strata from borehole SKB-1, Binja Block, South Karanpura Coalfield in Jharkhand. Based on the distribution pattern of age marker palynotaxa, two distinct palynoassemblages are identified. Palynoassemblage-I in the lithologically ...

Geological map of Uruguay Esc 1,100,000. Chafalote Sheet D-26

International Nuclear Information System (INIS)

Masquelin, H; Tabo, F

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Chafalote) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils. The area corresponding to Chafalote is located in central and eastern metamorphic formation constituted by Lavalleja-Rocha group

Geology of Sierra de San Miguel area Rocha department (Uruguay)

International Nuclear Information System (INIS)

Muzio, R.; Veroslavsky, G.; Morales, E. . E mail: rossana@fcien.edu.uy

2004-01-01

This paper is part of a regional study about Mesozoic magmatism, tectonics and sedimentation in Uruguay. As a result of the geological studies carried out in Sierra de San Miguel area (Rocha department), lithological descriptions, their stratigraphic relationships and their petrographic characterization are presented [es

Muddy lateral accretion and low stream power in a sub-recent confined channel belt, Rhine-Meuse delta, central Netherlands

NARCIS (Netherlands)

Makaske, B.; Weerts, H.J.T.

2005-01-01

The Hennisdijk fluvial system in the central Rhine-Meuse delta is an abandoned Rhine distributary that was active on a wide floodplain from 3800 to 3000 years BP. Cross-sectional geometry, lithological characteristics and planform patterns of the channel-belt deposits indicate lateral migration of

Controls on the molecular and carbon isotopic composition of organic matter deposited in a Kimmeridgian euxinic shelf sea: Evidence for preservation of carbohydrates through sulfurisation

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Kaam-Peters, H.M.E. van; Schouten, S.; Koster, J.

1998-01-01

Thirteen samples from the Kimmeridge Clay Formation (KCF) in Dorset, covering all different lithologies, were studied using bulk and molecular geochemical and microscopical techniques. Our data show that the positive correlation between TOC and 13CTOC reported for shales (Huc et al., 1992) also

Origin of brackish groundwater in a sandstone aquifer on Bornholm, Denmark

DEFF Research Database (Denmark)

Jørgensen, Niels Oluf; Heinemeier, Jan

2008-01-01

A multi-isotope approach in combination with hydrochemical data and borehole logging is applied to identify the source of brackish groundwater in a borehole in the well field of Neksø Municipal Waterworks in Bornholm, Denmark. The aquifer lithology consists of fractured Lower Cambrian sandstones...

Proterozoic intracontinental basin: The Vindhyan example

Indian Academy of Sciences (India)

basins display marked similarities in their lithology, depositional setting and stratigraphic architecture. (Naqvi and Rogers 1987). This note sum- marises the stratigraphy, stratal architecture, sed- imentology and geochronology of the Vindhyan. Supergroup occurring in the Son valley region. (figure 1). 2. The Vindhyan basin.

Rare earth elements in Japan Sea sediments and diagenetic behavior of Ce/Ce∗: results from ODP Leg 127

Science.gov (United States)

Murray, R.; Buchholtz ten Brink, Marilyn R.; Brumsack, Hans-Juergen; Gerlach, David C.; Russ III, G. Price

1991-01-01

The relative effects of paleoceanographic and paleogeographic variations, sediment lithology, and diagenetic processes on the recorded rare earth element (REE) chemistry of Japan Sea sediments are evaluated by investigating REE total abundances and relative fractionations in 59 samples from Ocean Drilling Program Leg 127.

Geological map of Uruguay Esc 1,100,000. Palmitas Sheet 0- 22

International Nuclear Information System (INIS)

Ford, I.; Gancio, F

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Molles) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils belong to the Proterozoic, Cretaceous, Tertiary and Quaternary period in Mercedes, Asencio, Palmitas and Fray Bentos formations

The role of a proto-Schelde River in the genesis of the southwestern Netherlands, inferred from the Quaternary successions and fossils in Moriaanshoofd borehole (Zeeland, the Netherlands)

NARCIS (Netherlands)

Slupik, A.A.; Wesselingh, F.P.; Mayhew, D.F.; Janse, A.C.; Dieleman, F.E.; Strydonck, M. van; Kiden, P.; Burger, A.W.; Reumer, J.W.F.

2013-01-01

We investigated the Quaternary lithological succession and faunas in a borehole near Moriaanshoofd (Province of Zeeland, SW Netherlands), in order to improve our understanding of the depositional context of classical Gelasian mammal faunas from the region. The fossils mostly derive from the base of

3-D numerical modelling of groundwater flow for scenario-based ...

African Journals Online (AJOL)

The data related to piezometric water levels, canal gauges, well logs, meteorological and lithological information were collected from Punjab Irrigation Department (PID), Water and Power Development Authority (WAPDA). Groundwater flow models for both steady and transient conditions were set-up using FEFLOW-3D.

Příspěvek k litologii křídových souvrství na profilu Bystrý potok u Trojanovic (slezská jednotka, vnější Západní Karpaty, Česká republika)

Czech Academy of Sciences Publication Activity Database

Boorová, D.; Jansa, L. F.; Matýsek, D.; Skupien, P.; Vašíček, Zdeněk

2008-01-01

Roč. 93, - (2008), s. 185-217 ISSN 1211-8796 Grant - others:GA ČR(CZ) GA205/05/0917 Program:GA Institutional research plan: CEZ:AV0Z30860518 Keywords : Silesian Unit * lithology * Lhoty - Mazák formations Subject RIV: DB - Geology ; Mineralogy

Mikropaleontologický výzkum svrchně pleistocenních sedimentů v pískovně u pístů

Czech Academy of Sciences Publication Activity Database

Hradecká, L.; Břízová, E.; Havlíček, P.; Svobodová, Marcela

2008-01-01

Roč. 2007, - (2008), s. 120-123 ISSN 0514-8057 Institutional research plan: CEZ:AV0Z30130516 Keywords : Quaternary sediments * lithology * palynology * Upper Cretaceous * foraminiferal and palynomorph redepositions Subject RIV: DB - Geology ; Mineralogy http://www.geology.cz/zpravy/obsah/2007/2007-33.pdf

Hydrostratigraphy and hydrogeology of the western part of Maira area, Khyber Pakhtunkhwa, Pakistan: A case study by using electrical resistivity

KAUST Repository

Farid, Asam M.; Jadoon, Khan; Akhter, Gulraiz; Iqbal, Muhammad Asim

2012-01-01

at the western part of the Maira area, Khyber Pakhtun Khwa, Pakistan. Aquifer lithology in the eastern part of the study area is dominated by coarse sand and gravel whereas the western part is characterized by fine sand. An attempt has been made to estimate

Lithologic log and interpretation of instrument logs NURE project, Carson Sink, Nevada, borehole

International Nuclear Information System (INIS)

Horton, R.C.

1978-04-01

No uranium mineralization was penetrated by the drilling. The uranium content of the rock units are within the usual range for unmineralized rocks of the types penetrated. Although the instrument logs indicated ample porosity in the sedimentary section, drill-stem tests in the intervals 699 to 722 ft, 3,692 to 3,734 ft, and 3,920 to 3,995 ft failed to recover any formation fluid. The instrument logs generally indicated low porosity and permeability in the volcanic rocks. The low permeability may have prohibited the circulation of ground water and possible supergene enrichment. The Carson Sink is a closed basin and all water is lost by evaporation, although there may be minor subsurface interbasin transfer. As the basin subsided dense connate water (brines) may have been trapped within the sediments making circulation of less dense water impossible. At present, nonsaline water is found only at shallow depths and is underlain by saline water. The hydrologic regime of the basin is complex and general assumptions should be made with care. Detailed analysis of hydrologic data may reveal zones of deep circulation. Reducing conditions, as evidenced by thin beds of organic rich material and pyrite, are present at depth. However, the unconsolidated sediments are young (Pleistocene to Recent) and perhaps too youthful for substantial mineralization to have occurred. No further deep drilling is recommended until the complex prehistoric hydrologic regime is studied. The study should include the geologic structural history of the basin and influence of Pleistocene and earlier pluvial cycles

Geological characterization and solute transport model investigations of contaminated sites in urban areas (Denmark)

DEFF Research Database (Denmark)

Andersen, Theis Raaschou; Poulsen, Søren Erbs; Thomsen, Peter

the two field sites includes only lithological profiles from boreholes. In order to increase the density of the field data, the two areas were mapped with Electrical Resistivity Tomography (ERT). Based on the borehole information and the high-density geophysical data, detailed 3D geological models...

Geological map of Uruguay Esc 1,100,000. El Ombu Sheet N-18

International Nuclear Information System (INIS)

Ford, I

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (El Ombu) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils belong to the Cretaceous, Tertiary and Quaternary period in Arapey, Mercedes, Asencio, Palmitas, Fray Bentos and Libertad formations

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Tectonic resettlement and lithological changes causes upwarpment of Mahakoshal rocks. In the present study, magnetic data interpretation is carried out for locating depth of causative body and delineating structural fault/dyke boundaries using Euler deconvolution technique. Most of the faults are oriented in the ENE–WSW ...

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

... with a particularly high statistical significance in spring and summer. Weak and inverse correlations between climatic and hydrological parameters can be explained by the role of other factors controlling the streamflow,both natural (soil and lithology) and anthropogenic (wetland drainage, water body conversion, dam and ...

Tectonic evolution of Tarim basin in Cambrian–Ordovician and its ...

Indian Academy of Sciences (India)

For different geodynamic settings of surrounding regions, there are different charac- teristics of depositional lithologies and lithofacies, sea-level change, distribution and migration of sed- imentary facies, etc., in the Tarim basin. Under the condition of regional extensional dynamic setting around Tarim Plate, there formed the ...

Time-transgressive tunnel valley formation indicated by infill sediment structure, North Sea - the role of glaciohydraulic supercooling

DEFF Research Database (Denmark)

Kristensen, Thomas Bojer; Piotrowski, Jan; Huuse, Mads

2008-01-01

Structure and lithology of the infill sediments from 16 subglacial buried tunnel valleys of Pleistocene age in the North Sea were analyzed using 3D seismic data and geophysical log data from five hydrocarbon exploration wells. The infill sediments are characterized by three seismic facies: Facies...

Smectite clay identification and quantification as an indicator of basic igneous rock durability

CSIR Research Space (South Africa)

Leyland, RC

2014-09-01

Full Text Available In terms of aerial extent, basic igneous rocks are one of the most used road building materials in South Africa. This is mainly due to the fact that approximately 57% of the surface lithology in South Africa is of poor road construction quality...

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Earth System Science. Anurag Tripathi. Articles written in Journal of Earth System Science. Volume 127 Issue 2 March 2018 pp 17. Lithologic boundaries from gravity and magnetic anomalies over Proterozoic Dalma volcanics · Pramod Kumar Yadav P K Adhikari Shalivahan Srivastava Ved P ...

Geological map of Uruguay Esc 1,100,000. Cerro Partido Sheet F-24

International Nuclear Information System (INIS)

Diaz, R; Albanell, H.; Bossi, J.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Cerro Partido) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils. The area corresponding to the Cerro Partido fotoplano is located in the orogenic belt or Don Feliciano belt

Estimation of the petrophysical parameters of sediments from Chad ...

African Journals Online (AJOL)

Porosity was estimated from three methods, and polynomial trends having fits ranging between 0.0604 and 0.478 describe depth - porosity variations. Interpretation of the trends revealed lithology trend that agree with the trends of shaliness. Estimates of average effective porosities of formations favorably compared with ...

Integrated geophysical investigation of the Igbara-Oke – Igbaraodo ...

African Journals Online (AJOL)

Along the failed segments, relatively thin (< 1.5 m) or non existing lateritic subgrade; low resistivity weathered layer(< 151 ohm-m);H type curve starting with decreasing resistivity typical of incompetent substratum and subsurface geological structures suspected to be faults, fractures, joints or lithologic boundaries ...

New insight into the microtexture of chalks from NMR analysis

DEFF Research Database (Denmark)

Faÿ-Gomord, Ophélie; Soete, Jeroen; Katika, Konstantina

2016-01-01

An integrated petrographical and petrophysical study was carried out on a set of 35 outcrop chalk samples, covering a wide range of lithologies and textures. In this study various chalk rock-types have been characterized, in terms of microtextures and porous network, by integrating both geologica...

Geological map of Uruguay Esc 1,100,000. Paso del Palmar Sheet N-19

International Nuclear Information System (INIS)

Ford, I.; Montana, J.; Morales, H.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Paso del Palmar) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils belong to Cretaceous, Tertiary and Quaternary period in San Gregorio, Arapey, Mercedes, Asencio and Fray Bentos formations

Geological map of Uruguay Esc 1,100,000. Cuchilla del Ombu. Sheet H-12

International Nuclear Information System (INIS)

Montana, J.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Cuchilla del Ombu) and the explanatory memoranda which describes the geological, lithological and sedimentological characteristics soils. In crystalline rocks have been recognized four basic units: porphyritic granite, Cunapiru granite, Cunapiru subvolcanic microgranite and metamorfites

A comparison of helicopter-borne electromagnetic systems for hydrogeologic studies

Science.gov (United States)

Bedrosian, Paul A.; Schamper, Cyril; Auken, Esben

2016-01-01

The increased application of airborne electromagnetic surveys to hydrogeological studies is driving a demand for data that can consistently be inverted for accurate subsurface resistivity structure from the near surface to depths of several hundred metres. We present an evaluation of three commercial airborne electromagnetic systems over two test blocks in western Nebraska, USA. The selected test blocks are representative of shallow and deep alluvial aquifer systems with low groundwater salinity and an electrically conductive base of aquifer. The aquifer units show significant lithologic heterogeneity and include both modern and ancient river systems. We compared the various data sets to one another and inverted resistivity models to borehole lithology and to ground geophysical models. We find distinct differences among the airborne electromagnetic systems as regards the spatial resolution of models, the depth of investigation, and the ability to recover near-surface resistivity variations. We further identify systematic biases in some data sets, which we attribute to incomplete or inexact calibration or compensation procedures.

Magnetic Susceptibility as a Tool for Investigating Igneous Rocks—Experience from IODP Expedition 304

Directory of Open Access Journals (Sweden)

Roger C. Searle

2008-07-01

Full Text Available Continuous measurements of magnetic susceptibility have been commonly used on Ocean Drilling Program (ODP and Integrated Ocean Drilling Program (IODPexpeditions to study minor lithological variations (forexample, those related to climatic cycles in sedimentary rocks, but they have been less frequently used on igneous rocks, although important post-cruise studies have utilized them (e.g., Ildefonse and Pezard, 2001. Here I report its use (and that of the closely related electrical conductivity on IODP Expedition 304 to examine igneous crustal rocks. Expedition 304/305 targeted the Atlantis Massif, an oceanic core complex on the Mid-Atlantic Ridge, and recovered a suite of igneous rocks comprising mainly gabbros, troctolites, and some diabases (Blackman et al., 2006; Ildefonse et al., 2006, 2007; IODP Expeditions 304 and 305 Scientists, 2005. Shipboard measurements (on D/V JOIDES Resolution of physical properties were made to characterize lithological units and alteration products, to correlate cored material with down-hole logging data, and to interpret broader-scale geophysical data.

Flammable gas production in Land 2 and Land 3/4 radioactive waste repositories

International Nuclear Information System (INIS)

1988-02-01

Geological, radiolytic and microbiological sources of gas are considered in relation to Land 2 and Land 3/4 type radioactive waste repositories. Geological sources are potentially the most troublesome and it is concluded that site investigation work should be designed to detect gas trap structures, reservoir lithologies or source rocks. Known source and reservoir lithologies should not be considered as suitable for the siting of waste repositories. Radiolytic and microbiological sources will depend on waste characteristics. A detailed review of the literature on radiolytic gas generation is presented and conclusions from this work indicate that water in waste and matrix should be kept to a minimum. Similarly, the level of radioactivity stored in each waste container should be kept to the minimum compatible with the storage design. Microbiological gas sources will be reduced by maintaining the cellulose content of the waste at a minimum. It is suggested that the removal of organics from the waste stream would be beneficial in terms of potential gas production. (author)

Prospectivity Modeling of Karstic Groundwater Using a Sequential Exploration Approach in Tepal Area, Iran

Science.gov (United States)

Sharifi, Fereydoun; Arab-Amiri, Ali Reza; Kamkar-Rouhani, Abolghasem; Yousefi, Mahyar; Davoodabadi-Farahani, Meysam

2017-09-01

The purpose of this study is water prospectivity modeling (WPM) for recognizing karstic water-bearing zones by using analyses of geo-exploration data in Kal-Qorno valley, located in Tepal area, north of Iran. For this, a sequential exploration method applied on geo-evidential data to delineate target areas for further exploration. In this regard, two major exploration phases including regional and local scales were performed. In the first phase, indicator geological features, structures and lithological units, were used to model groundwater prospectivity as a regional scale. In this phase, for karstic WPM, fuzzy lithological and structural evidence layers were generated and combined using fuzzy operators. After generating target areas using WPM, in the second phase geophysical surveys including gravimetry and geoelectrical resistivity were carried out on the recognized high potential zones as a local scale exploration. Finally the results of geophysical analyses in the second phase were used to select suitable drilling locations to access and extract karstic groundwater in the study area.

Review article "Remarks on factors influencing shear wave velocities and their role in evaluating susceptibilities to earthquake-triggered slope instability: case study for the Campania area (Italy"

Directory of Open Access Journals (Sweden)

V. Paoletti

2012-07-01

Full Text Available Shear wave velocities have a fundamental role in connection with the mitigation of seismic hazards, as their low values are the main causes of site amplification phenomena and can significantly influence the susceptibility of a territory to seismic-induced landslides. The shear wave velocity (Vs and modulus (G of each lithological unit are influenced by factors such as the degree of fracturing and faulting, the porosity, the clay amount and the precipitation, with the latter two influencing the unit water content. In this paper we discuss how these factors can affect the Vs values and report the results of different analyses that quantify the reduction in the rock Vs and shear modulus values connected to the presence of clay and water. We also show that significant results in assessing seismic-induced slope failure susceptibility for land planning targets could be achieved through a careful evaluation, based only on literature studies, of the geo-lithological and geo-seismic features of the study area.

Integrated techniques to evaluate the features of sedimentary rocks of archaeological areas of Sicily

Directory of Open Access Journals (Sweden)

Maria Brai

2004-02-01

Full Text Available Sicily includes a great variety of lithologies, giving a high complexity to the geologic landscape. Their prevalent lithology is sedimentary. It is well known that rocks of sedimentary origin, compared with metamorphic and volcanic deposits, can be relatively soft and hence fairly easy to model. Nevertheless, this workability advantage is a drawback for Cultural Heritage applications. In fact, these materials show a high porosity, with pore-size distributions that lead to deterioration through absorption of water. In this paper, several sedimentary rocks used in historical Cultural Heritage items of Sicily, from "Magna Graecia" to nowadays, are classified for mineralogical features, chemical composition, and for porosity. Particularly, some samples collected in quarries relevant to the archaeological sites of 41 Agrigento, Segesta and Selinunte will be considered and characterized using integrated techniques (XRD, XRF, NMR and CT. Data on samples obtained in laboratory will be compared with the relevant values measured in situ on monuments of historical-cultural interest of the quoted archaeological places.

Radiometric characterisation of more representative natural building materials in the province of Rome

International Nuclear Information System (INIS)

Trevisi, R.; Bruno, M.; Orlando, C.; Ocone, R.; Paolelli, C.; Amici, M.; Altieri, A.; Antonelli, B.

2005-01-01

Natural building materials, characterised by middle-low-activity concentrations of primordial radionuclides ( 40 K, 232 Th and 238 U series) are widely used in Italy. Since natural materials reflect the geological variability of their sites of origin, a systematic study was carried out in the province of Rome and the results are reported in this paper. In the present work, in order to evaluate average, minimum and maximum contents of primordial radionuclides, more representative lithologies outcropping on the territory of the province of Rome were identified and around 150 samples were collected. Also, these lithologies were characterised from a radioprotection point of view, by means of the evaluation of the index, I, when they are used as building materials. The results confirm the high-primordial radionuclide content within some materials used in Latium (central Italy). Although the study was carried out in a limited area, the results confirm considerable variation in the primordial radionuclide content depending on the sites of origin. (authors)

Analysis on depositional system and discussion on ore-formation conditions of channel sandstone type uranium deposit. Taking Dongsheng area, Ordos meso-cenozoic basin as an example

International Nuclear Information System (INIS)

Wu Rengui; Yu Dagan; Zhu Minqiang; Zhou Wanpeng; Chen Anping

2003-01-01

Applying the theory of depositional system, the depositional facies and depositional systems of the Zhiluo Formation in Dongsheng area are systematically analysed, and the authors proposed that sediments of the Zhiluo Formation are of fluvial facies, and streams of the Zhiluo time experienced three evolution stages, namely: the early braided stream, the middle low sinuosity meandering stream and the late high sinuosity meandering stream. Based on features of paleoclimatic evolution, the Zhiluo Formation is divided into two lithological members. The lower lithological member consists of sediments of braided and low sinuosity meandering streams under humid-ward paleoclimatic conditions forming grey sedimentary formation. The upper member is composed of sediments of meandering streams under arid-hot paleoclimatic conditions representing complex-colored (mainly red) sedimentary formation. It is suggested that uranium mineralization in the study area is of channel sandstone type and controlled by braided channel sediments. Besides, the ore-formation conditions for channel sandstone type uranium deposit are preliminarily discussed

Climate and cultural history of the Northeastern Yucatan Peninsula, Quintana Roo, Mexico

Energy Technology Data Exchange (ETDEWEB)

Hodell, D.A. [Department of Geological Sciences, University of Florida, 241 Williamson Hall, P.O. Box 112120, Gainesville, FL 32611 (United States); Brenner, M.; Curtis, J.H. [Land Use and Environmental Change Institute (LUECI), University of Florida, Gainesville, FL (United States)

2007-07-15

We inferred the Holocene paleoclimate history of the northeastern Yucatan Peninsula, Mexico, by studying stratigraphic variations in stable isotopes (d 18O and d 13C) and lithologic properties (organic matter and carbonate content) in sediment cores taken in 6.3 and 16.2 m of water from Lake Punta Laguna. We present a simple model to explain the lithologic and isotopic variations, and discuss the inferred paleoclimate history in terms of its relation to ancient Maya cultural development. We find evidence for lower lake level and drier climate at about the same time as each major discontinuity in Maya cultural history: Preclassic Abandonment (150-250 A.D.), Maya Hiatus (534 to 593 A.D.), Terminal Classic Collapse (750-1050 A.D.), and Postclassic Abandonment (mid-fifteenth century). Although these broad temporal correlations suggest climate played a role in Maya cultural evolution, chronological uncertainties preclude a detailed analysis of climate changes and archaeologically documented cultural transformations.

Regional magnetic and gravity features of the Gibson Dome area and surrounding region, Paradox Basin, Utah : a preliminary report

Science.gov (United States)

Hildenbrand, T.G.; Kucks, R.P.

1983-01-01

Analyses of regional gravity and magnetic anomaly maps have been carried out to assist in the evaluation of the Gibson Dome area as a possible repository site for high-level radioactive waste. Derivative, wavelength-filtered, and trend maps were compiled to aid in properly locating major geophysical trends corresponding to faults, folds, and lithologic boundaries. The anomaly maps indicate that Paradox Basin is characterized by a heterogeneous Precambrian basement, essentially a metamorphic complex of gneisses and schist intruded by granitic rocks and mafic to ultramafic bodies. Interpreted Precambrian structures trend predominantly northwest and northeast although east-west trending features are evident. Prominent gravity lows define the salt anticlines. Structural and lithologic trends in the Gibson Dome area are closely examined. Of greatest interest is a series of circular magnetic highs trending west-northwest into the Gibson Dome area. Further study of the exact definition and geologic significance of this series of anomalies is warranted.

A geological-radiometric uranium survey in the Tlaxiaco area of the State of Oaxaca

International Nuclear Information System (INIS)

Guillen R, O.E.

1981-01-01

Explorations were effected in the northwestern part of the State of Oaxaca neighbouring the city of Tlaxiaco and lying within the Oaxaca-Mixteca province. The survey comprised a regional area of 642.2.K, in which abnormalities auspicious to the presence of mineral uranium had previously been found. The area of interest, initially limited to a strip 10 kilometers long by 1/2 kilometers wide, showed evidence, however, of an even greater extension. Among the lithological units found of predominate interest were clastic, sedimentary rocks, mezozoic carbonate rocks, and extrusive and intrusive igneous rocks. From the high radiometric values obtained, the extrusive pyroclastic rocks showed more favourable signs of the presence of uranium ore and were considered of chief uranium significance in the area. Minerological, structural and lithological detectors (guides) have been set up in the area for an extensive location of abnormalities. The work based on regionally conducted geological and radiological surveys followed by detailed area of interest studies. (author)

Influence of production method on physical and chemical properties of Kumkol petroleum; Vliyanie sposoba dobychi na fiziko-khimicheskie svojstva Kumkol`skoj nefti

Energy Technology Data Exchange (ETDEWEB)

Ajdarbaev, A S; Nadirov, A N; Musaeva, Z G

1997-11-04

Industrial petroleum and gas content of Kumkol deposit is determined. It dated to Lower Neocomian and Upper Jurassic terrigenous stage sediments. It is determined, that its lithologic characteristics are very different. That is explained by various condition of sedimentation. (author) 11 refs., 5 tabs. Suppl. Neft` i gaz Kazakhstana

Morphometric and landuse analysis: implications on flood hazards ...

African Journals Online (AJOL)

This study assessed the morphometric, landuse and lithological attributes of five basins (Iwaraja, Ilesa, Olupona, Osogbo I and Osogbo II) with particular reference to flood hazards in Ilesa and Osogbo metropolis, Osun State Nigeria. Ilesa town is situated within Iwaraja and Ilesa basins while Osogbo metropolis spread ...

Vertical Electrical Sounding as a Viable Tool for Investigating ...

African Journals Online (AJOL)

... in the range 0.50m- 180.0m and thicknesses in the range 0.50m-75.0m. Area of probable subsurface lithological formations and their thicknesses have been identified for economical purposes, environmental purposes, engineering purposes, especially for future, mining of industries foundation operations and drilling.

Integrating Stable Isotope - Reactive Transport Model Approach for Assessment of Chlorinated Solvent Degradation

Science.gov (United States)

2016-06-01

aerobic cometabolism, reductive dechlorination evidence was reported from the toe of the plume, where TCE enters the Lower Lithologic Unit. The CSM of the...modeling in reactive transport: 50 years of artificial recharge in the Amsterdam Water Supply Dunes . J. Hydrology 454: 7-25. Khan, F. I., et al

A sequence of events across the Cretaceous-Tertiary boundary

NARCIS (Netherlands)

Smit, J.; Romein, A.J.T.

1985-01-01

The lithological and biological sequence of events across the Cretaceous-Tertiary (K/T), as developed in thick and complete landbased sections and termed the standard K/T event sequence, is also found in many DSDP cores from all over the globe. Microtektite-like spherules have been found in