78 FR 21839 - Drawbridge Operation Regulation; Green River, Small-house, KY and Black River, Jonesboro, LA

Science.gov (United States)

2013-04-12

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 117 [Docket No. USCG-2013-0041] RIN 1625-AA09 Drawbridge Operation Regulation; Green River, Small-house, KY and Black River, Jonesboro, LA... drawbridge operation regulation for the drawbridges across Green River, mile 79.6, Small- house, KY and Black...

Intercontinental dispersal of giant thermophilic ants across the Arctic during early Eocene hyperthermals

Science.gov (United States)

Archibald, S. Bruce; Johnson, Kirk R.; Mathewes, Rolf W.; Greenwood, David R.

2011-01-01

Early Eocene land bridges allowed numerous plant and animal species to cross between Europe and North America via the Arctic. While many species suited to prevailing cool Arctic climates would have been able to cross throughout much of this period, others would have found dispersal opportunities only during limited intervals when their requirements for higher temperatures were met. Here, we present Titanomyrma lubei gen. et sp. nov. from Wyoming, USA, a new giant (greater than 5 cm long) formiciine ant from the early Eocene (approx. 49.5 Ma) Green River Formation. We show that the extinct ant subfamily Formiciinae is only known from localities with an estimated mean annual temperature of about 20°C or greater, consistent with the tropical ranges of almost all of the largest living ant species. This is, to our knowledge, the first known formiciine of gigantic size in the Western Hemisphere and the first reported cross-Arctic dispersal by a thermophilic insect group. This implies intercontinental migration during one or more brief high-temperature episodes (hyperthermals) sometime between the latest Palaeocene establishment of intercontinental land connections and the presence of giant formiciines in Europe and North America by the early middle Eocene. PMID:21543354

New Eocene damselflies and first Cenozoic damsel-dragonfly of the isophlebiopteran lineage (Insecta: Odonata).

Science.gov (United States)

Garrouste, Romain; Nel, André

2015-10-09

The study of a new specimen of Petrolestes hendersoni from the Eocene Green Formation allows a more precise description of the enigmatic damselfly and the diagnosis of the Petrolestini. Petrolestes messelensis sp. nov. is described from the Eocene Messel Formation in Germany, extending the distribution of the Petrolestini to the European Eocene. The new damsel-dragonfly family Pseudostenolestidae is described for the new genus and species Pseudostenolestes bechlyi, from the Eocene Messel Formation. It is the first Cenozoic representative of the Mesozoic clade Isophlebioptera.

Summary of the engineering assessment of inactive uranium mill tailings, Green River site, Green River, Utah

International Nuclear Information System (INIS)

1981-08-01

Radon gas released from the 123,000 tons of tailings at the Green River site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The five alternative actions range from millsite decontamination with the addition of 3 m of stabilization cover material, to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the five options range from about $4,300,000 for stabilization in-place, to about $9,600,000 for disposal at a distance of about 30 miles. Three principal alternatives for the reprocessing of the Green River tailings were examined: heap leaching, treatment at an existing mill, and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $1,800/lb by heap leach and $1,600/lb by conventional plant processes

Eocene and Miocene extension, meteoric fluid infiltration, and core complex formation in the Great Basin (Raft River Mountains, Utah)

Science.gov (United States)

Methner, Katharina; Mulch, Andreas; Teyssier, Christian; Wells, Michael L.; Cosca, Michael A.; Gottardi, Raphael; Gebelin, Aude; Chamberlain, C. Page

2015-01-01

Metamorphic core complexes (MCCs) in the North American Cordillera reflect the effects of lithospheric extension and contribute to crustal adjustments both during and after a protracted subduction history along the Pacific plate margin. While the Miocene-to-recent history of most MCCs in the Great Basin, including the Raft River-Albion-Grouse Creek MCC, is well documented, early Cenozoic tectonic fabrics are commonly severely overprinted. We present stable isotope, geochronological (40Ar/39Ar), and microstructural data from the Raft River detachment shear zone. Hydrogen isotope ratios of syntectonic white mica (δ2Hms) from mylonitic quartzite within the shear zone are very low (−90‰ to −154‰, Vienna SMOW) and result from multiphase synkinematic interaction with surface-derived fluids. 40Ar/39Ar geochronology reveals Eocene (re)crystallization of white mica with δ2Hms ≥ −154‰ in quartzite mylonite of the western segment of the detachment system. These δ2Hms values are distinctively lower than in localities farther east (δ2Hms ≥ −125‰), where 40Ar/39Ar geochronological data indicate Miocene (18–15 Ma) extensional shearing and mylonitic fabric formation. These data indicate that very low δ2H surface-derived fluids penetrated the brittle-ductile transition as early as the mid-Eocene during a first phase of exhumation along a detachment rooted to the east. In the eastern part of the core complex, prominent top-to-the-east ductile shearing, mid-Miocene 40Ar/39Ar ages, and higher δ2H values of recrystallized white mica, indicate Miocene structural and isotopic overprinting of Eocene fabrics.

Long-term surveillance plan for the Green River, Utah, disposal site

International Nuclear Information System (INIS)

1997-06-01

The long-term surveillance plan (LTSP) for the Green River, Utah, Uranium Mill Tailings Remedial Action (UMTRA) Project disposal site describes the surveillance activities for the Green River disposal cell. The U.S. Department of Energy (DOE) will carry out these activities to ensure that the disposal cell continues to function as designed. This final LTSP was prepared as a requirement for acceptance under the U.S. Nuclear Regulatory Commission (NRC) general license for custody and long-term care of residual radioactive materials (RRM). This LTSP documents whether the land and interests are owned by the United States or an Indian tribe and details how the long-term care of the disposal site will be carried out. The Green River, Utah, LTSP is based on the DOE's Guidance for Implementing the UMTRA Project Long-term Surveillance Program (DOE, 1992a)

Remedial action at the Green River uranium mill tailings site, Green River, Utah: Environmental assessment

International Nuclear Information System (INIS)

1988-07-01

The inactive Green River uranium mill tailings site is one mile southeast of Green River, Utah. The existing tailings pile is within the floodplain boundaries of the 100-year and 500-year flood events. The 48-acre designated site contains eight acres of tailings, the mill yard and ore storage area, four main buildings, a water tower, and several small buildings. Dispersion of the tailings has contaminated an additional 24 acres surrounding the designated site. Elevated concentrations of molybdenum, nitrate, selenium, uranium, and gross alpha activity exceed background levels and the proposed US Environmental Protection Agency (EPA) maximum concentration limits in the groundwater in the unconsolidated alluvium and in the shallow shales and limestones beneath the alluvium at the mill tailings site. The contamination is localized beneath, and slightly downgradient of, the tailings pile. The proposed action is to relocate the tailings and associated contaminated materials to an area 600 feet south of the existing tailings pile where they would be consolidated into one, below-grade disposal cell. A radon/infiltration barrier would be constructed to cover the stabilized pile and various erosion control measures would be taken to ensure the long-term stability of the stabilized pile. 88 refs., 12 figs., 20 tabs

78 FR 31454 - Drawbridge Operation Regulation; Hudson River, Troy and Green Island, NY

Science.gov (United States)

2013-05-24

...-AA09 Drawbridge Operation Regulation; Hudson River, Troy and Green Island, NY AGENCY: Coast Guard, DHS... that governs the highway bridge (Troy Green Island) across the Hudson River, mile 152.7, between Troy... the regulations for the 112th Street Bridge, mile 155.4, between Troy and Cohoes which has been...

78 FR 56607 - Drawbridge Operation Regulation; Hudson River, Troy and Green Island, NY

Science.gov (United States)

2013-09-13

...-AA09 Drawbridge Operation Regulation; Hudson River, Troy and Green Island, NY AGENCY: Coast Guard, DHS... operation of the highway bridge across the Hudson River, mile 152.7, between Troy and Green Island, New York... Street Bridge, mile 155.4, between Troy and Cohoes which has been converted to a fixed bridge. It is...

Simulation of blue and green water resources in the Wei River basin, China

Directory of Open Access Journals (Sweden)

Z. Xu

2014-09-01

Full Text Available The Wei River is the largest tributary of the Yellow River in China and it is suffering from water scarcity and water pollution. In order to quantify the amount of water resources in the study area, a hydrological modelling approach was applied by using SWAT (Soil and Water Assessment Tool, calibrated and validated with SUFI-2 (Sequential Uncertainty Fitting program based on river discharge in the Wei River basin (WRB. Sensitivity and uncertainty analyses were also performed to improve the model performance. Water resources components of blue water flow, green water flow and green water storage were estimated at the HRU (Hydrological Response Unit scales. Water resources in HRUs were also aggregated to sub-basins, river catchments, and then city/region scales for further analysis. The results showed that most parts of the WRB experienced a decrease in blue water resources between the 1960s and 2000s, with a minimum value in the 1990s. The decrease is particularly significant in the most southern part of the WRB (Guanzhong Plain, one of the most important grain production basements in China. Variations of green water flow and green water storage were relatively small on the spatial and temporal dimensions. This study provides strategic information for optimal utilization of water resources and planning of cultivating seasons in the Wei River basin.

Phase II, Title I engineering assessment of inactive uranium mill tailings, Green River Site, Green River, Utah

International Nuclear Information System (INIS)

1977-12-01

An engineering assessment was performed of the problems resulting from the existence of radioactive uranium mill tailings at the Green River site, Utah. Services included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting radiation exposures of individuals and nearby populations , the investigation of site hydrology and meteorology and the evaluation and costing of alternative corrective actions. Radon gas release from the 123 thousand tons of tailings at the Green River site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The three alternative actions presented are dike stabilization, fencing, on- and off-site decontamination and maintenance (Option I); improvements in the stabilization cover and diking plus cleanup of the site and Browns Wash, and realignment of Browns Wash (Option II); and addition of stabilization cover to a total of 2 ft, realignment of Browns Wash and placement of additional riprap, on-site cleanup and drainage improvements (Option III). All options include remedial action at off-site structures. Cost estimates for the three options range from $700,000 to $926,000

Heavy mineral delineation of the Cretaceous, Paleocene, and Eocene stratigraphic sections at the Savannah River Site, Upper Coastal Plain of South Carolina

International Nuclear Information System (INIS)

Cathcart, E.M.; Sargent, K.A.

1994-01-01

The Upper Atlantic Coastal Plain of South Carolina consists of a fluvial-deltaic and shallow marine complex of unconsolidated sediments overlying the crystalline basement rocks of the North American continent. Because of the lateral and vertical variability of these sediments, stratigraphic boundaries have been difficult to distinguish. Portions of the Cretaceous, Paleocene, and eocene stratigraphic sections from cores recovered during the construction of two monitoring wells at the Savannah River Site were studied to determine if heavy mineral suites could be utilized to distinguish boundaries. The stratigraphic sections include: the Late Cretaceous Middendorf, Black Creek, and Steel Creek Formations, the Paleocene Snapp Formation, the late Paleocene-Early Eocene Fourmile Branch Formation, and the Early Eocene Congaree formation. In previous studies composite samples were taken over 2.5 ft. intervals along the cores and processed using a heavy liquid for heavy mineral recovery. During this study, heavy mineral distributions were determined by binocular microscope and the mineral identifications confirmed by x-ray diffraction analysis of hand-picked samples. The heavy mineral concentration data and grain size data were then compared to the stratigraphic boundary positions determined by other workers using more classical methods. These comparisons were used to establish the utility of this method for delineating the stratigraphic boundaries in the area of study

Diachronous ranges of benthonic Foraminifera in the Eocene of Alabama and South Carolina

International Nuclear Information System (INIS)

Willard, G.D.; Fallaw, W.C.; Snipes, D.S.

1994-01-01

Seventeen species of benthonic Foraminifera reported by Bandy (1949) from the Eocene of Little Stave Creek in Clarke County, Alabama were identified from the middle eocene Santee Limestone and the upper Eocene Dry Branch Formation in Aiken and Barnwell counties, South Carolina. Of the 17 species, seven occurred in South Carolina stratigraphically above or below the ranges listed by Bandy. Bandy made a detailed study of Foraminifera from the Claibornian and Jacksonian Tallahatta, Lisbon, Gosport, Moodys Branch, and Yazoo formations exposed on Little Stave Creek and plotted the stratigraphic ranges within the section of numerous species. The authors' samples came from well cores at the Savannah River Site in South Carolina. Of 13 species from the middle Eocene Santee and also reported by Bandy, four are stratigraphically below the lowest occurrence listed by Bandy, and one is stratigraphically above the highest occurrence. Of four species from the upper Eocene Dry Branch Formation and also listed by Bandy, two are stratigraphically above his highest occurrence. Dockery and Nystrom (1992) and Campbell (1993) have described diachroneity among mollusks in the Eocene of South Carolina. Caution should be used in relying on a small number of species in correlating Eocene deposits in the Atlantic and Gulf coastal plains

Study of a conceptual nuclear energy center at Green River, Utah: water allocation issues

International Nuclear Information System (INIS)

Harper, N.J.

1982-04-01

According to preliminary studies, operation of a nine-reactor Nuclear Energy Center near Green River, Utah would require the acquisition of 126,630 acre-feet per year. Groundwater aquifers are a potential source of supply but do not present a viable option at this time due to insufficient data on aquifer characteristics. Surface supplies are available from the nearby Green and San Rafael Rivers, tributaries of the Colorado River, but are subject to important constraints. Because of these constraints, the demand for a dependable water supply for a Nuclear Energy Center could best be met by the acquisition of vested water rights from senior appropriators in either the Green or San Rafael Rivers. The Utah Water Code provides a set of procedures to accomplish such a transfer of water rights

Polar constituents isolated from Green River oil shale

Energy Technology Data Exchange (ETDEWEB)

Anders, D.E.; Doolittle, F.G.; Robinson, W.E.

1975-01-01

The mass spectrometric, ir absorption, and NMR data were interpreted for 22 compounds obtained from a polar fraction of Green River shale. The major constituents analyzed are believed to be of the following compositional types: C/sub n/H/sub 2n/O (cyclohexanols and chain isoprenoid ketones), C/sub n/H/sub 2n-10/O (tetralones and indanones), C/sub n/H/sub 2n-7/N (tetrahydroquinolines), C/sub n/H/sub 2n-11/N(quinolines), C/sub n/H/sub 2n-1/NO (alkoxypyrrolines), C/sub n/H/sub 2n-5/NO/sub 2/ (maleimides), C/sub n/H/sub 2n-8/ (tetralins), C/sub n/H/sub 2n-12/ (naphthalenes) and C/sub n/H/sub 2n-14/ (benzylbenzenes). This work expands the present information about nitrogen, oxygen and aromatic constituents indigenous to Green River shale.

Processesof Tamarix invasion and floodplain development along the lower Green River, Utah.

Science.gov (United States)

Birken, Adam S; Cooper, David J

2006-06-01

Significant ecological, hydrologic, and geomorphic changes have occurred during the 20th century along many large floodplain rivers in the American Southwest. Native Populus forests have declined, while the exotic Eurasian shrub, Tamarix, has proliferated and now dominates most floodplain ecosystems. Photographs from late 19th and early 20th centuries illustrate wide river channels with largely bare in-channel landforms and shrubby higher channel margin floodplains. However, by the mid-20th century, floodplains supporting dense Tamarix stands had expanded, and river channels had narrowed. Along the lower Green River in eastern Utah, the causal mechanism of channel and floodplain changes remains ambiguous due to the confounding effects of climatically driven reductions in flood magnitude, river regulation by Flaming Gorge Dam, and Tamarix invasion. This study addressed whether Tamarix establishment and spread followed climate- or dam-induced reductions in annual peak flows or whether Tamarix was potentially a driver of floodplain changes. We aged 235 Tamarix and 57 Populus individuals, determined the hydrologic and geomorphic processes that controlled recruitment, identified the spatial relationships of germination sites within floodplain stratigraphic transects, and mapped woody riparian vegetation cohorts along three segments of the lower Green River. The oldest Tamarix established along several sampling reaches in 1938, and 1.50-2.25 m of alluvium has accreted above their germination surfaces. Nearly 90% of the Tamarix and Populus samples established during flood years that exceeded the 2.5-year recurrence interval. Recruitment was most common when large floods were followed by years with smaller peak flows. The majority of Tamarix establishment and Green River channel narrowing occurred long before river regulation by Flaming Gorge Dam. Tamarix initially colonized bare instream sand deposits (e.g., islands and bars), and most channel and floodplain changes

78 FR 39608 - Safety Zone; Summer in the City Water Ski Show; Fox River, Green Bay, WI

Science.gov (United States)

2013-07-02

...-AA00 Safety Zone; Summer in the City Water Ski Show; Fox River, Green Bay, WI AGENCY: Coast Guard, DHS... River in Green Bay, WI. This safety zone is intended to restrict vessels from a portion of the Fox River... Waterboard Warrior Ski Team will perform two 30-minute shows on the Fox River between the Hwy 141 Bridge and...

CORE-BASED INTEGRATED SEDIMENTOLOGIC, STRATIGRAPHIC, AND GEOCHEMICAL ANALYSIS OF THE OIL SHALE BEARING GREEN RIVER FORMATION, UINTA BASIN, UTAH

Energy Technology Data Exchange (ETDEWEB)

Lauren P. Birgenheier; Michael D. Vanden Berg,

2011-04-11

An integrated detailed sedimentologic, stratigraphic, and geochemical study of Utah's Green River Formation has found that Lake Uinta evolved in three phases (1) a freshwater rising lake phase below the Mahogany zone, (2) an anoxic deep lake phase above the base of the Mahogany zone and (3) a hypersaline lake phase within the middle and upper R-8. This long term lake evolution was driven by tectonic basin development and the balance of sediment and water fill with the neighboring basins, as postulated by models developed from the Greater Green River Basin by Carroll and Bohacs (1999). Early Eocene abrupt global-warming events may have had significant control on deposition through the amount of sediment production and deposition rates, such that lean zones below the Mahogany zone record hyperthermal events and rich zones record periods between hyperthermals. This type of climatic control on short-term and long-term lake evolution and deposition has been previously overlooked. This geologic history contains key points relevant to oil shale development and engineering design including: (1) Stratigraphic changes in oil shale quality and composition are systematic and can be related to spatial and temporal changes in the depositional environment and basin dynamics. (2) The inorganic mineral matrix of oil shale units changes significantly from clay mineral/dolomite dominated to calcite above the base of the Mahogany zone. This variation may result in significant differences in pyrolysis products and geomechanical properties relevant to development and should be incorporated into engineering experiments. (3) This study includes a region in the Uinta Basin that would be highly prospective for application of in-situ production techniques. Stratigraphic targets for in-situ recovery techniques should extend above and below the Mahogany zone and include the upper R-6 and lower R-8.

Long-term surveillance plan for the Green River, Utah disposal site. Revision 1

International Nuclear Information System (INIS)

1994-08-01

The long-term surveillance plan (LTSP) for the Green River, Utah, Uranium Mill Tailings Remedial Action (UMTRA) Project disposal site describes the surveillance activities for the Green River disposal cell. The US Department of Energy (DOE) will carry out these activities to ensure that the disposal cell continues to function as designed. This final LTSP was prepared as a requirement for acceptance under the US Nuclear Regulatory Commission (NRC) general license for custody and long-term care of residual radioactive materials (RRM). This LTSP documents whether the land and interests are owned by the United States or an Indian tribe and details how the long-term care of the disposal site will be carried out. The Green River, Utah, LTSP is based on the DOE's Guidance for Implementing the UMTRA Project Long-term Surveillance Program (DOE, 1992a)

High resolution cyclostratigraphy of the early Eocene – new insights into the origin of the Cenozoic cooling trend

Directory of Open Access Journals (Sweden)

T. Westerhold

2009-07-01

Full Text Available Here we present a high-resolution cyclostratigraphy based on X-ray fluorescence (XRF core scanning data from a new record retrieved from the tropical western Atlantic (Demerara Rise, ODP Leg 207, Site 1258. The Eocene sediments from ODP Site 1258 cover magnetochrons C20 to C24 and show well developed cycles. This record includes the missing interval for reevaluating the early Eocene part of the Geomagnetic Polarity Time Scale (GPTS, also providing key aspects for reconstructing high-resolution climate variability during the Early Eocene Climatic Optimum (EECO. Detailed spectral analysis demonstrates that early Eocene sedimentary cycles are characterized by precession frequencies modulated by short (100 kyr and long (405 kyr eccentricity with a generally minor obliquity component. Counting of both the precession and eccentricity cycles results in revised estimates for the duration of magnetochrons C21r through C24n. Our cyclostratigraphic framework also corroborates that the geochronology of the Eocene Green River Formation (Wyoming, USA is still questionable mainly due to the uncertain correlation of the "Sixth tuff" to the GPTS.

Right at the onset of the long-term Cenozoic cooling trend the dominant eccentricity-modulated precession cycles of ODP Site 1258 are interrupted by strong obliquity cycles for a period of ~800 kyr in the middle of magnetochron C22r. These distinct obliquity cycles at this low latitude site point to (1 a high-latitude driving mechanism on global climate variability from 50.1 to 49.4 Ma, and (2 seem to coincide with a significant drop in atmospheric CO₂ concentration below a critical threshold between 2- and 3-times the pre-industrial level (PAL. The here newly identified orbital configuration of low eccentricity in combination with high obliquity amplitudes during this ~800-kyr period and the crossing of a critical pCO₂ threshold may have led to the formation of the first ephemeral

75 FR 30299 - Drawbridge Operation Regulations; Fox River, Green Bay, WI

Science.gov (United States)

2010-06-01

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 117 [Docket No. USCG-2010-0374] Drawbridge Operation Regulations; Fox River, Green Bay, WI AGENCY: Coast Guard, DHS. ACTION: Notice of temporary... from the regulation governing the operation of the Main Street Bridge at Mile 1.21 over the Fox River...

Summary of sediment data from the Yampa river and upper Green river basins, Colorado and Utah, 1993-2002

Science.gov (United States)

Elliott, John G.; Anders, Steven P.

2004-01-01

The water resources of the Upper Colorado River Basin have been extensively developed for water supply, irrigation, and power generation through water storage in upstream reservoirs during spring runoff and subsequent releases during the remainder of the year. The net effect of water-resource development has been to substantially modify the predevelopment annual hydrograph as well as the timing and amount of sediment delivery from the upper Green River and the Yampa River Basins tributaries to the main-stem reaches where endangered native fish populations have been observed. The U.S. Geological Survey, in cooperation with the Colorado Division of Wildlife and the U.S. Fish and Wildlife Service, began a study to identify sediment source reaches in the Green River main stem and the lower Yampa and Little Snake Rivers and to identify sediment-transport relations that would be useful in assessing the potential effects of hydrograph modification by reservoir operation on sedimentation at identified razorback spawning bars in the Green River. The need for additional data collection is evaluated at each sampling site. Sediment loads were calculated at five key areas within the watershed by using instantaneous measurements of streamflow, suspended-sediment concentration, and bedload. Sediment loads were computed at each site for two modes of transport (suspended load and bedload), as well as for the total-sediment load (suspended load plus bedload) where both modes were sampled. Sediment loads also were calculated for sediment particle-size range (silt-and-clay, and sand-and-gravel sizes) if laboratory size analysis had been performed on the sample, and by hydrograph season. Sediment-transport curves were developed for each type of sediment load by a least-squares regression of logarithmic-transformed data. Transport equations for suspended load and total load had coefficients of determination of at least 0.72 at all of the sampling sites except Little Snake River near

Summary of the Phase II, Title I engineering assessment of inactive uranium mill tailings, Green River Site, Green River, Utah

International Nuclear Information System (INIS)

1977-12-01

An engineering assessment was performed of the problems resulting from the existence of radioactive uranium mill tailings at the Green River site, Utah. The services include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting radiation exposures of individuals and nearby populations, the investigation of site hydrology and meteorology and the evaluation and costing of alternative corrective actions. Radon gas release from the 123 thousand tons of tailings at the Green River site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The three alternative actions presented are dike stabilization, fencing, on- and off-site decontamination and maintenance; improvements in the stabilization cover and diking plus cleanup of the site and Browns Wash, and realignment of Browns Wash; and addition of stabilization cover to a total of 2 ft, realignment of Browns Wash and placement of additional riprap, on-site cleanup and drainage improvements. All options include remedial action at off-site structures. Cost estimates for the three options range from $700,000 to $926,000

Specific Conductance and Dissolved-Solids Characteristics for the Green River and Muddy Creek, Wyoming, Water Years 1999-2008

Science.gov (United States)

Clark, Melanie L.; Davidson, Seth L.

2009-01-01

Southwestern Wyoming is an area of diverse scenery, wildlife, and natural resources that is actively undergoing energy development. The U.S. Department of the Interior's Wyoming Landscape Conservation Initiative is a long-term science-based effort to assess and enhance aquatic and terrestrial habitats at a landscape scale, while facilitating responsible energy development through local collaboration and partnerships. Water-quality monitoring has been conducted by the U.S. Geological Survey on the Green River near Green River, Wyoming, and Muddy Creek near Baggs, Wyoming. This monitoring, which is being conducted in cooperation with State and other Federal agencies and as part of the Wyoming Landscape Conservation Initiative, is in response to concerns about potentially increased dissolved solids in the Colorado River Basin as a result of energy development. Because of the need to provide real-time dissolved-solids concentrations for the Green River and Muddy Creek on the World Wide Web, the U.S. Geological Survey developed regression equations to estimate dissolved-solids concentrations on the basis of continuous specific conductance using relations between measured specific conductance and dissolved-solids concentrations. Specific conductance and dissolved-solids concentrations were less varied and generally lower for the Green River than for Muddy Creek. The median dissolved-solids concentration for the site on the Green River was 318 milligrams per liter, and the median concentration for the site on Muddy Creek was 943 milligrams per liter. Dissolved-solids concentrations ranged from 187 to 594 milligrams per liter in samples collected from the Green River during water years 1999-2008. Dissolved-solids concentrations ranged from 293 to 2,485 milligrams per liter in samples collected from Muddy Creek during water years 2006-08. The differences in dissolved-solids concentrations in samples collected from the Green River compared to samples collected from Muddy

Geomorphic Drainage Capture Recorded by Oxygen Isotopes of Green River Formation Lacustrine Mudstone, Eocene, Wyoming

Science.gov (United States)

Doebbert, A. C.; Booth, A. L.; Carroll, A.; Chamberlain, C.; Rhodes, M.

2005-12-01

The isotopic composition of cement and other meteoric precipitates are increasingly being used to interpret orogenic uplift histories, based on the relationship between altitude and rainwater δ18O. However, other variables such as changing regional drainage patterns may also affect the downstream composition of surface waters, especially when multiple drainages commingle in a lake. The Green River Formation contains some of the best documented lacustrine deposits in the world, making it ideal for examining such issues. Carbonate mudstone in balanced-fill facies of the lower LaClede Bed averages 3.41‰ (PDB), and records a deep, saline to brackish lake that fluctuated near its sill. In contrast, overfilled facies of the upper LaClede Bed record a freshwater lake, and δ18O reaches values as low as -9.72‰. This transition occurred shortly after deposition of the Analcite Tuff at 48.94 ± 0.12 Ma (Smith et al., 2003), and was geologically abrupt. Based on 40Ar/39Ar-calibrated sediment accumulation rates it required no more than 200-300 ky. An almost identical transition occurs in two cores separated by about 30 km, making local diagenesis an unlikely cause. The magnitude of δ18O change is similar to that in some uplift studies, but its rapidity virtually excludes uplift as a controlling mechanism. Instead, we propose that both the change in sedimentation and the sharp decrease in δ18O are the result of a drainage capture event. The addition of a new drainage to the basin may have adjusted isotopic values in two ways: by introducing runoff with relatively low δ18O, and by decreasing residence time (and therefore evaporation) of lake water. Decreasing 87Sr/86Sr across the same transition suggests that the newly added waters may have been sourced from rising volcanic topography to the north in the Absaroka province. Although this rising topography allows for the possibility of some uplift component, the rate of change in lacustrine δ18O is consistent with

78 FR 33049 - Intent to Prepare an Environmental Impact Statement for the Green River/Tusher Diversion Dam...

Science.gov (United States)

2013-06-03

..., Salt Lake City, Utah 84138-1100, or via email at bronson.smart@ut.usda.gov . Information may also be... publicly available at any time during the EIS process. FOR FURTHER INFORMATION CONTACT: Mr. Bronson Smart... held on November 15, 2012 at Green River City Hall in Green River, Utah. Through additional...

UMTRA water sampling and analysis plan, Green River, Utah

International Nuclear Information System (INIS)

Papusch, R.

1993-12-01

The purpose of this water sampling and analysis plan (WSAP) is to provide a basis for groundwater and surface water sampling at the Green River Uranium Mill Tailing Remedial Action (UMTRA) Project site. This WSAP identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequency for the monitoring locations

2012 Reassessment of Floodplain Wetland Connections in the Middle Green River, Utah

Energy Technology Data Exchange (ETDEWEB)

LaGory, Kirk E. [Argonne National Lab. (ANL), Argonne, IL (United States); Walston, Leroy J. [Argonne National Lab. (ANL), Argonne, IL (United States); Weber, Cory C. [Argonne National Lab. (ANL), Argonne, IL (United States)

2016-12-01

This report presents the results of floodplain wetland connection surveys conducted in 2012 at eight priority floodplain wetlands along the middle Green River between Jensen and Ouray, Utah. Surveys were conducted at levee breaches and within channels leading from the breaches to the wetlands (referred to here as connection channels) to characterize the flows needed to connect the river's main channel with the floodplain wetlands.

Long-term surveillance plan for the Green River, Utah disposal site. Revision 2

International Nuclear Information System (INIS)

1998-07-01

The long-term surveillance plan (LTSP) for the Green River, Utah, Uranium Mill Tailings Remedial Action (UMTRA) Project disposal site describes the surveillance activities for the Green River disposal cell. The US Department of Energy (DOE) will carry out these activities to ensure that the disposal cell continues to function as designed. This final LTSP was prepared as a requirement for acceptance under the US Nuclear Regulatory Commission (NRC) general license for custody and long-term care of residual radioactive materials (RRM). This LTSP documents whether the land and interests are owned by the United States or an Indian tribe and details how the long-term care of the disposal site will be carried out

Snowmelt runoff in the Green River basin derived from MODIS snow extent

Science.gov (United States)

Barton, J. S.; Hall, D. K.

2011-12-01

The Green River represents a vital water supply for southwestern Wyoming, northern Colorado, eastern Utah, and the Lower Colorado River Compact states (Arizona, Nevada, and California). Rapid development in the southwestern United States combined with the recent drought has greatly stressed the water supply of the Colorado River system, and concurrently increased the interest in long-term variations in stream flow. Modeling of snowmelt runoff represents a means to predict flows and reservoir storage, which is useful for water resource planning. An investigation is made into the accuracy of the Snowmelt Runoff Model of Martinec and Rango, driven by Moderate Resolution Imaging Spectroradiometer (MODIS) snow maps for predicting stream flow within the Green River basin. While the moderate resolution of the MODIS snow maps limits the spatial detail that can be captured, the daily coverage is an important advantage of the MODIS imagery. The daily MODIS snow extent is measured using the most recent clear observation for each 500-meter pixel. Auxiliary data used include temperature and precipitation time series from the Snow Telemetry (SNOTEL) and Remote Automated Weather Station (RAWS) networks as well as from National Weather Service records. Also from the SNOTEL network, snow-water equivalence data are obtained to calibrate the conversion between snow extent and runoff potential.

Assessment of spatial and temporal patterns of green and blue water flows under natural conditions in inland river basins in Northwest China

Directory of Open Access Journals (Sweden)

C. F. Zang

2012-08-01

Full Text Available In arid and semi-arid regions freshwater resources have become scarcer with increasing demands from socio-economic development and population growth. Until recently, water research and management has mainly focused on blue water but ignored green water. Furthermore, in data poor regions hydrological flows under natural conditions are poorly characterised but are a prerequisite to inform future water resources management. Here we report on spatial and temporal patterns of both blue and green water flows that can be expected under natural conditions as simulated by the Soil and Water Assessment Tool (SWAT for the Heihe river basin, the second largest inland river basin in Northwest China. Calibration and validation at two hydrological stations show good performance of the SWAT model in modelling hydrological processes. The total green and blue water flows were 22.05–25.51 billion m³ in the 2000s for the Heihe river basin. Blue water flows are larger in upstream sub-basins than in downstream sub-basins mainly due to high precipitation and a large amount of snow and melting water in upstream. Green water flows are distributed more homogeneously among different sub-basins. The green water coefficient was 87%–89% in the 2000s for the entire river basin, varying from around 80%–90% in up- and mid-stream sub-basins to above 90% in downstream sub-basins. This is much higher than reported green water coefficients in many other river basins. The spatial patterns of green water coefficients were closely linked to dominant land covers (e.g. snow cover upstream and desert downstream and climate conditions (e.g. high precipitation upstream and low precipitation downstream. There are no clear consistent historical trends of change in green and blue water flows and the green water coefficient at both the river basin and sub-basin levels. This study provides insights into green and blue water endowments under natural conditions for the entire

First known feeding trace of the eocene bottom-dwelling fish Notogoneus osculus and its paleontological significance.

Directory of Open Access Journals (Sweden)

Anthony J Martin

Full Text Available BACKGROUND: The Green River Formation (early Eocene, about 42-53 Ma at and near Fossil Butte National Monument in Wyoming, USA, is world famous for its exquisitely preserved freshwater teleost fish in the former Fossil Lake. Nonetheless, trace fossils attributed to fish interacting with the lake bottom are apparently rare, and have not been associated directly with any fish species. Here we interpret the first known feeding and swimming trace fossil of the teleost Notogoneus osculus Cope (Teleostei: Gonorynchidae, which is also represented as a body fossil in the same stratum. METHODOLOGY/PRINCIPAL FINDINGS: A standard description of the trace fossil, identified as Undichna cf. U. simplicatas, was augmented by high-resolution digital images and spatial and mathematical analyses, which allowed for detailed interpretations of the anatomy, swimming mode, feeding behavior, and body size of the tracemaker. Our analysis indicates that the tracemaker was about 45 cm long; used its caudal, anal, and pelvic fins (the posterior half of its body to make the swimming traces; and used a ventrally oriented mouth to make overlapping feeding marks. We hypothesize that the tracemaker was an adult Notogoneus osculus. CONCLUSIONS/SIGNIFICANCE: Our results are the first to link a specific teleost tracemaker with a trace fossil from the Green River Formation, while also interpreting the size and relative age of the tracemaker. The normal feeding and swimming behaviors indicated by the trace fossil indicate temporarily oxygenated benthic conditions in the deepest part of Fossil Lake, counter to most paleoecological interpretations of this deposit. Lastly, our spatial and mathematical analyses significantly update and advance previous approaches to the study of teleost trace fossils.

Oil Recovery Increases by Low-Salinity Flooding: Minnelusa and Green River Formations

Energy Technology Data Exchange (ETDEWEB)

Eric P. Robertson

2010-09-01

Waterflooding is by far the most widely used method in the world to increase oil recovery. Historically, little consideration has been given in reservoir engineering practice to the effect of injection brine composition on waterflood displacement efficiency or to the possibility of increased oil recovery through manipulation of the composition of the injected water. However, recent work has shown that oil recovery can be significantly increased by modifying the injection brine chemistry or by injecting diluted or low salinity brine. This paper reports on laboratory work done to increase the understanding of improved oil recovery by waterflooding with low salinity injection water. Porous media used in the studies included outcrop Berea sandstone (Ohio, U.S.A.) and reservoir cores from the Green River formation of the Uinta basin (Utah, U.S.A.). Crude oils used in the experimental protocols were taken from the Minnelusa formation of the Powder River basin (Wyoming, U.S.A.) and from the Green River formation, Monument Butte field in the Uinta basin. Laboratory corefloods using Berea sandstone, Minnelusa crude oil, and simulated Minnelusa formation water found a significant relationship between the temperature at which the oil- and water-saturated cores were aged and the oil recovery resulting from low salinity waterflooding. Lower aging temperatures resulted in very little to no additional oil recovery, while cores aged at higher temperatures resulted in significantly higher recoveries from dilute-water floods. Waterflood studies using reservoir cores and fluids from the Green River formation of the Monument Butte field also showed significantly higher oil recoveries from low salinity waterfloods with cores flooded with fresher water recovering 12.4% more oil on average than those flooded with undiluted formation brine.

Passifloraceae seeds from the late Eocene of Colombia.

Science.gov (United States)

Martínez, Camila

2017-12-01

The plant fossil record for the neotropics is still sparse and temporally discontinuous. The location and description of new fossil material are fundamental for understanding evolutionary and biogeographic patterns of lineages. A new fossil record of Passifloraceae from the late Eocene of Colombia is described in this study. Plant fossils were collected from a new locality from the Eocene Esmeraldas Formation. Eighteen fossil seeds were selected, described, and compared with fossil and extant angiosperm seeds based on the literature and herbarium collections. Taxonomic affinities of the fossil seeds within Passifloraceae s.l. were evaluated by comparing morphological characters of the seeds in a phylogenetic context. Stratigraphic information associated with the fossil locality was used to interpret the environment and taphonomic processes associated with fossil deposition. A new seed fossil genus and species, Passifloroidesperma sogamosense gen. and sp. nov., is described and associated with the subfamily Passifloroideae based on the presence of a foveolate seed surface, ruminate endosperm, and a seed coat with prismatic palisade cells. The depositional environment of the locality is described as a floodplain associated with river channels. A detailed review of the Passifloraceae fossil record indicates that P. sogamosense is the oldest confirmed record of Passifloraceae. Its late Eocene age provides a minimum age that can be used as a calibration point for the crown Passifloroideae node in future dating analyses that together with its neotropical geographic location can shed light on the origin and diversification of the subfamily. © 2017 Botanical Society of America.

Irrigation drainwater effects on the endangered larval razorback sucker and bonytail in the middle Green River

International Nuclear Information System (INIS)

Hamilton, S.J.; Buhl, K.J.

1994-01-01

The Department of the Interior (DOI) irrigation drainwater investigation of the middle Green River of Utah reported that concentrations of boron, selenium, and zinc in water, bottom sediment, and biological tissues were sufficiently elevated to be potentially harmful to fish and wildlife. The major focus of the DOI study was in the Ashley Creek-Stewart Lake area near Jensen, utah. The middle Green River provides sensitive habitat for the endangered Colorado squawfish, razorback sucker, and bonytail. The authors conducted two 90-day chronic toxicity studies, one with razorback sucker, and the other with bonytail. Swimup larvae were exposed in a reconstituted water simulating the middle Green River. The toxicant mixture simulated the environmental ratio and concentrations of inorganics reported in the DOI study for the mouth of Ashley Creek-Stewart Lake outflow on the Green River, and was composed of arsenic, boron, copper, molybdenum, uranium, vanadium, selenate, selenite, and zinc. The mixture was tested at 1X, 2X, 4X, 8X, and 16X where X was the average expected environmental concentration. Razorback suckers had reduced survival after 40 days exposure to the inorganic mixture at 16X and after 60 days at 8X; whereas growth was reduced after 30 days at 8X and after 60 days at 4X. Bonytail had reduced survival after 20 days exposure at 16X, whereas growth was reduced after 60 days at 8X. These studies show that at environmentally realistic concentrations, the inorganic mixture simulating Ashley Creek-Stewart Lake outfall adversely affects larval endangered fish

Hydrogeology, groundwater levels, and generalized potentiometric-surface map of the Green River Basin lower Tertiary aquifer system, 2010–14, in the northern Green River structural basin

Science.gov (United States)

Bartos, Timothy T.; Hallberg, Laura L.; Eddy-Miller, Cheryl

2015-07-14

In cooperation with the Bureau of Land Management, groundwater levels in wells located in the northern Green River Basin in Wyoming, an area of ongoing energy development, were measured by the U.S. Geological Survey from 2010 to 2014. The wells were completed in the uppermost aquifers of the Green River Basin lower Tertiary aquifer system, which is a complex regional aquifer system that provides water to most wells in the area. Except for near perennial streams, groundwater-level altitudes in most aquifers generally decreased with increasing depth, indicating a general downward potential for groundwater movement in the study area. Drilled depth of the wells was observed as a useful indicator of depth to groundwater such that deeper wells typically had a greater depth to groundwater. Comparison of a subset of wells included in this study that had historical groundwater levels that were measured during the 1960s and 1970s and again between 2012 and 2014 indicated that, overall, most of the wells showed a net decline in groundwater levels.

Radioactive contamination of filamentous green algae in the Hungarian reach of the river Danube

International Nuclear Information System (INIS)

Holland, E.; Sztanyik, L.B.; Vanicsek, L.

1982-01-01

In accordance with the Hungarian nuclear power program, river water monitoring techniques should be developed. From among algae of various species of river Danube the localized and well-propagating filamentous green algae (Cladophora sp.; Vaucheria sp.) were investigated. The activity concentration of gamma-radiating nuclides absorbed by algae was determined with a Canberra 8100 type Ge(Li)-spectrometer. This apparatus facilitated radioactivity measurements on wet samples or samples subjected to simple physical preparation. The metabolic character and accumulative abilities of filamentous green algae showed that they are suitable indicators of radionuclide contamination of the water ecosystem. 131 I nuclide at min. 72.5 mBq/g to max. 5440.0 mBq/g, and other fission products from 55 mBq/g to 929 mBq/g were observed. (author)

Radioactive contamination of filamentous green algae in the Hungarian reach of the river Danube

Energy Technology Data Exchange (ETDEWEB)

Holland, E.; Sztanyik, L.B.; Vanicsek, L. (Orszagos Frederic Joliot-Curie Sugarbiologiai es Sugaregeszseguegyi Kutato Intezet, Budapest (Hungary))

1982-01-01

In accordance with the Hungarian nuclear power program, river water monitoring techniques should be developed. From among algae of various species of river Danube the localized and well-propagating filamentous green algae (Cladophora sp.; Vaucheria sp.) were investigated. The activity concentration of gamma-radiating nuclides absorbed by algae was determined with a Canberra 8100 type Ge(Li)-spectrometer. This apparatus facilitated radioactivity measurements on wet samples or samples subjected to simple physical preparation. The metabolic character and accumulative abilities of filamentous green algae showed that they are suitable indicators of radionuclide contamination of the water ecosystem. /sup 131/I nuclide at min. 72.5 mBq/g to max. 5440.0 mBq/g, and other fission products from 55 mBq/g to 929 mBq/g were observed.

Capturing the Green River -- Multispectral airborne videography to evaluate the environmental impacts of hydropower operations

International Nuclear Information System (INIS)

Snider, M.A.; Hayse, J.W.; Hlohowskyj, I.; LaGory, K.E.

1996-01-01

The 500-mile long Green River is the largest tributary of the Colorado River. From its origin in the Wind River Range mountains of western Wyoming to its confluence with the Colorado River in southeastern Utah, the Green River is vital to the arid region through which it flows. Large portions of the area remain near-wilderness with the river providing a source of recreation in the form of fishing and rafting, irrigation for farming and ranching, and hydroelectric power. In the late 1950's and early 1960's hydroelectric facilities were built on the river. One of these, Flaming Gorge Dam, is located just south of the Utah-Wyoming border near the town of Dutch John, Utah. Hydropower operations result in hourly and daily fluctuations in the releases of water from the dam that alter the natural stream flow below the dam and affect natural resources in and along the river corridor. In the present study, the authors were interested in evaluating the potential impacts of hydropower operations at Flaming Gorge Dam on the downstream natural resources. Considering the size of the area affected by the daily pattern of water release at the dam as well as the difficult terrain and limited accessibility of many reaches of the river, evaluating these impacts using standard field study methods was virtually impossible. Instead an approach was developed that used multispectral aerial videography to determine changes in the affected parameters at different flows, hydrologic modeling to predict flow conditions for various hydropower operating scenarios, and ecological information on the biological resources of concern to assign impacts

Socioeconomic impacts: study of a conceptual nuclear energy center at Green River, Utah

International Nuclear Information System (INIS)

Weaver, R.; Taylor, J.; Burnett, K.; Greenberg, B.

1982-02-01

This document constitutes a segment of a feasibility study investigating the ramifications of constructing a nuclear energy center (NEC) in an arid western region. In this phase of the study, the impacts on socioeconomic conditions in the surrounding communities and possible ways of financing and mitigating these impacts were examined. The general conclusion reached is that the socioeconomic impacts of a nuclear energy center in the Green River area of Southeastern Utah would not impose an absolute bar to NEC development. The economy of the NEC impact area would be substantially transformed by the NEC. In particular, Green River city itself would change from its current status as a relatively stable rural economy with an agricultural, mining, and recreation base to a major city with over 20,000 permanent relatively high income residents. The NEC, by itself, would provide a tax base more than adequate to finance required expansion of public facilities and public human service provisions

Socioeconomic impacts: study of a conceptual nuclear energy center at Green River, Utah

Energy Technology Data Exchange (ETDEWEB)

Weaver, R.; Taylor, J.; Burnett, K.; Greenberg, B.

1982-02-01

This document constitutes a segment of a feasibility study investigating the ramifications of constructing a nuclear energy center (NEC) in an arid western region. In this phase of the study, the impacts on socioeconomic conditions in the surrounding communities and possible ways of financing and mitigating these impacts were examined. The general conclusion reached is that the socioeconomic impacts of a nuclear energy center in the Green River area of Southeastern Utah would not impose an absolute bar to NEC development. The economy of the NEC impact area would be substantially transformed by the NEC. In particular, Green River city itself would change from its current status as a relatively stable rural economy with an agricultural, mining, and recreation base to a major city with over 20,000 permanent relatively high income residents. The NEC, by itself, would provide a tax base more than adequate to finance required expansion of public facilities and public human service provisions.

Bioavailability of iron and zinc in green leafy vegetables growing in river side and local areas of Allahabad district

Directory of Open Access Journals (Sweden)

Bhawna Srivastava

2014-01-01

Full Text Available Introduction: Green Leafy Vegetables (GLVs are the treasure trove of many micronutrients.Objective: The aim of the study is to find out the commonly growing vegetables in river side and local areas of Allahabad district and to access the bioavailability of iron and zinc in selected green leafy vegetables of river side and local areas of Allahabad district.Methods: Five to four commonly grown green leafy vegetables were selected from the Arailghat, Baluaghat, Gaughat, Mahewa, Muirabad, Rajapur, Rasullabad for the study. Total iron and zinc in sample were estimated by AOAC (2005 and bioavailability of zinc and iron from various food samples was determined in vitro method described by Luten (1996. Appropriate statistical technique was adopted for analysis of study.Result: Soya leaves, Radish leaves, Amaranth, Spinach were grown in both the areas except Kulpha and Karamwa, which are commonly grown in river side area. There was a significant difference between the bioavailability of iron and zinc in GLV grown in local and river side area.Conclusion: Hence it can be concluded that there is a contamination of heavy metals which binds with the iron and zinc and make them less bioavailable in the selected GLV.

Early Eocene birds from La Borie, southern France

DEFF Research Database (Denmark)

Bourdon, Estelle; Mourer-Chauviré, Cécile; Laurent, Yves

2016-01-01

The Early Eocene locality of La Borie is located in the village of Saint-Papoul, in southern France. These Eocene fluvio-lacustrine clay deposits have yielded numerous vertebrate remains. Mammalian taxa found in the fossiliferous levels indicate an age near the reference level MP 8–9, which...... corresponds to the middle Ypresian, Lower Eocene. Here we provide a detailed description of the avian remains that were preliminarily reported in a recent study of the vertebrate fauna from La Borie. A maxilla, a quadrate, cervical vertebrae, a femur and two tibiotarsi are assigned to the giant ground bird...... Gastornis parisiensis Hébert, 1855 (Gastornithidae). These new avian remains add to the fossil record of Gastornis, which is known from the Upper Paleocene to Middle Eocene of Europe, Early Eocene of Asia, and Early Eocene of North America. Gastornis parisiensis differs from the North American Gastornis...

Stratigraphy of Eocene Sediments in the Soutwest Thrace

Directory of Open Access Journals (Sweden)

Muhsin SÜMENGEN

1991-06-01

Full Text Available The area concerned is situated in the Gelibolu peninsula, north of the Saros Bay and northwest of the Marmara sea sediments of Upper Cretaceous to Miocene age, having a variety of fades crop out SW of Thrace. During the present survey, the goal was to examine the stratigraphic features of the Eocene sediments in the region. The Tertiary basin is underlain by an ophiolitic complex emplaced prior to Maastrichtian and limestone of Maastrichtian to Palaeocene age. The base of the limestone is not exposed within the region. The Tertiary transgression began in the Early Eocene in the Gelibolu peninsula. Massive mudstones, sandstone sequences that become thicker and coarser upward, and channel fill sediments are the first products of this transgression (Karaağaç limanı formation. This sequence is overlain by deltaic sediments beginning with massive mudstones and becoming thicker and coarser upward (Koyun limanı formation. These sediments are conformably and transitionally overlain by interbedded mudstone and sandstone, cut by channel fill deposits (Rcitepe formation. This formation was formed by meandering rivers. The sea that progressed inward to the Gelibolu peninsula during the Early Eocene began to become shallower again at the beginning of Lutetian and as a result, the region as a whole became a positive area during the Middle Lutetian. During the Late Lutetian, a new transgression occurred in the entire region. The first product of this transgression was a limestone (Soğucak formation. This limestone which was deposited in a shallow sea environment is locally intercalated with sandstone and conglomerate. The sea became deeper from the beginning of Upper Eocene. Firstly, turbiditic sandstone, and mudstone interbedded hemipelagic mudstone (Gaziköy formation with tuff, and carbonate mudstone and massive mudstone (Burgaz formation were deposited. These units are products of flat basins. These are, in turn, overlain by sequences consisting of

Green-blue water in the city: quantification of impact of source control versus end-of-pipe solutions on sewer and river floods.

Science.gov (United States)

De Vleeschauwer, K; Weustenraad, J; Nolf, C; Wolfs, V; De Meulder, B; Shannon, K; Willems, P

2014-01-01

Urbanization and climate change trends put strong pressures on urban water systems. Temporal variations in rainfall, runoff and water availability increase, and need to be compensated for by innovative adaptation strategies. One of these is stormwater retention and infiltration in open and/or green spaces in the city (blue-green water integration). This study evaluated the efficiency of three adaptation strategies for the city of Turnhout in Belgium, namely source control as a result of blue-green water integration, retention basins located downstream of the stormwater sewers, and end-of-pipe solutions based on river flood control reservoirs. The efficiency of these options is quantified by the reduction in sewer and river flood frequencies and volumes, and sewer overflow volumes. This is done by means of long-term simulations (100-year rainfall simulations) using an integrated conceptual sewer-river model calibrated to full hydrodynamic sewer and river models. Results show that combining open, green zones in the city with stormwater retention and infiltration for only 1% of the total city runoff area would lead to a 30 to 50% reduction in sewer flood volumes for return periods in the range 10-100 years. This is due to the additional surface storage and infiltration and consequent reduction in urban runoff. However, the impact of this source control option on downstream river floods is limited. Stormwater retention downstream of the sewer system gives a strong reduction in peak discharges to the receiving river. However due to the difference in response time between the sewer and river systems, this does not lead to a strong reduction in river flood frequency. The paper shows the importance of improving the interface between urban design and water management, and between sewer and river flood management.

Profundal sideritic mudstone from an Eocene lake in Alaska

International Nuclear Information System (INIS)

Dickinson, K.A.

1987-01-01

Sideritic lacustrine mudstone was found in drill core from a uranium deposit in the Death Valley area in the eastern part of the Seward Peninsula, Alaska. The precursor sediments for this rock were deposited in an unusual iron-meromictic Eocene lake, herein named Lake Tubutulik, which occupied part of the Boulder Creek basin, a graben that is probably a southern extension of the larger Death Valley basin. The Boulder Creek basin is bounded on the west by granite of the Upper Cretaceous Darby pluton and on the east by Precambrian to Paleozoic metasedimentary rocks. The lake basin was formed by basaltic flows that dammed the valley of the ancestral Tubutulik River in early Eocene time. The lake sediments included a nearshore facies of fine-grained organic mud and an offshore facies of laminated sideritic mud. The offshore (profundal) laminated mudstone consists of alternating layers of authigenic siderite and detrital grains, mostly quartz and clay minerals. Both lacustrine facies contain turbidites. The lacustrine rocks graded laterally into an onshore facies of colluvial and fluvial sandstone, paludal mudstone, and coal. The ancient lake occupied a small, deep basin in a tectonically active area of high relief. Meromixis was apparently stabilized by reduced iron and bicarbonate dissolved in the monimolimnion. The intensity of meromixis decreased as the lake became shallower from sediment filling. The source of the dissolved iron in the monoimolimnion was probably the Eocene basalt. Carbon isotope analysis of the siderite suggests that the dissolved bicarbonate in the profundal facies was largely inorganic. Sideritic carbon in one sample from the onshore paludal facies has an isotopic signature (δ 13 C = +16.9) consistent with residual carbonate formed during methanogenic fermentation

Acoustic tag detections of green sturgeon in the Columbia River and Coos Bay estuaries, Washington and Oregon, 2010–11

Science.gov (United States)

Hansel, Hal C.; Romine, Jason G.; Perry, Russell W.

2017-11-08

The Columbia River, in Washington and Oregon, and Coos Bay, in Oregon, are economically important shipping channels that are inhabited by several fishes protected under the Endangered Species Act (ESA). Maintenance of shipping channels involves dredge operations to maintain sufficient in-channel depths to allow large ships to navigate the waterways safely. Fishes entrained by dredge equipment often die or experience delayed mortality. Other potential negative effects of dredging include increased turbidity, reductions in prey resources, and the release of harmful contaminants from the dredged sediments. One species of concern is the ESA-listed green sturgeon (Acipenser medirostris; Southern Distinct Population Segment). In this study, we used acoustic telemetry to identify habitat use, arrival and departure timing, and the extent of upstream migration of green sturgeon in the Columbia River and Coos Bay to help inform dredge operations to minimize potential take of green sturgeon. Autonomous acoustic receivers were deployed in Coos Bay from the mouth to river kilometer (rkm) 21.6 from October 2009 through October 2010. In the Columbia River Estuary, receivers were deployed between the mouth and rkm 37.8 from April to November in 2010 and 2011. A total of 29 subadult and adult green sturgeon were tagged with temperature and pressure sensor tags and released during the study, primarily in Willapa Bay and Grays Harbor, Washington, and the Klamath River, Oregon. Green sturgeon detected during the study but released by other researchers also were included in the study.The number of tagged green sturgeon detected in the two estuaries differed markedly. In Coos Bay, only one green sturgeon was detected for about 2 hours near the estuary mouth. In the Columbia River Estuary, 9 green sturgeon were detected in 2010 and 10 fish were detected in 2011. Green sturgeon entered the Columbia River from May through October during both years, with the greatest numbers of fish being

Early Eocene deep-sea benthic foraminiferal faunas: Recovery from the Paleocene Eocene Thermal Maximum extinction in a greenhouse world

Science.gov (United States)

Thomas, Ellen; D’haenens, Simon; Speijer, Robert P.; Alegret, Laia

2018-01-01

The early Eocene greenhouse world was marked by multiple transient hyperthermal events. The most extreme was the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma), linked to the extinction of the globally recognised deep-sea benthic foraminiferal Velasco fauna, which led to the development of early Eocene assemblages. This turnover has been studied at high resolution, but faunal development into the later early Eocene is poorly documented. There is no widely accepted early Eocene equivalent of the Late Cretaceous-Paleocene Velasco fauna, mainly due to the use of different taxonomic concepts. We compiled Ypresian benthic foraminiferal data from 17 middle bathyal-lower abyssal ocean drilling sites in the Pacific, Atlantic and Indian Oceans, in order to characterise early Eocene deep-sea faunas by comparing assemblages across space, paleodepth and time. Nuttallides truempyi, Oridorsalis umbonatus, Bulimina trinitatensis, the Bulimina simplex group, the Anomalinoides spissiformis group, pleurostomellids, uniserial lagenids, stilostomellids and lenticulinids were ubiquitous during the early Eocene (lower-middle Ypresian). Aragonia aragonensis, the Globocassidulina subglobosa group, the Cibicidoides eocaenus group and polymorphinids became ubiquitous during the middle Ypresian. The most abundant early Ypresian taxa were tolerant to stressed or disturbed environments, either by opportunistic behavior (Quadrimorphina profunda, Tappanina selmensis, Siphogenerinoides brevispinosa) and/or the ability to calcify in carbonate-corrosive waters (N. truempyi). Nuttallides truempyi, T. selmensis and other buliminids (Bolivinoides cf. decoratus group, Bulimina virginiana) were markedly abundant during the middle Ypresian. Contrary to the long-lived, highly diverse and equitable Velasco fauna, common and abundant taxa reflect highly perturbed assemblages through the earliest Ypresian, with lower diversity and equitability following the PETM extinction. In contrast, the middle Ypresian

Early Eocene deep-sea benthic foraminiferal faunas: Recovery from the Paleocene Eocene Thermal Maximum extinction in a greenhouse world.

Directory of Open Access Journals (Sweden)

Gabriela J Arreguín-Rodríguez

Full Text Available The early Eocene greenhouse world was marked by multiple transient hyperthermal events. The most extreme was the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma, linked to the extinction of the globally recognised deep-sea benthic foraminiferal Velasco fauna, which led to the development of early Eocene assemblages. This turnover has been studied at high resolution, but faunal development into the later early Eocene is poorly documented. There is no widely accepted early Eocene equivalent of the Late Cretaceous-Paleocene Velasco fauna, mainly due to the use of different taxonomic concepts. We compiled Ypresian benthic foraminiferal data from 17 middle bathyal-lower abyssal ocean drilling sites in the Pacific, Atlantic and Indian Oceans, in order to characterise early Eocene deep-sea faunas by comparing assemblages across space, paleodepth and time. Nuttallides truempyi, Oridorsalis umbonatus, Bulimina trinitatensis, the Bulimina simplex group, the Anomalinoides spissiformis group, pleurostomellids, uniserial lagenids, stilostomellids and lenticulinids were ubiquitous during the early Eocene (lower-middle Ypresian. Aragonia aragonensis, the Globocassidulina subglobosa group, the Cibicidoides eocaenus group and polymorphinids became ubiquitous during the middle Ypresian. The most abundant early Ypresian taxa were tolerant to stressed or disturbed environments, either by opportunistic behavior (Quadrimorphina profunda, Tappanina selmensis, Siphogenerinoides brevispinosa and/or the ability to calcify in carbonate-corrosive waters (N. truempyi. Nuttallides truempyi, T. selmensis and other buliminids (Bolivinoides cf. decoratus group, Bulimina virginiana were markedly abundant during the middle Ypresian. Contrary to the long-lived, highly diverse and equitable Velasco fauna, common and abundant taxa reflect highly perturbed assemblages through the earliest Ypresian, with lower diversity and equitability following the PETM extinction. In contrast, the

Early Eocene deep-sea benthic foraminiferal faunas: Recovery from the Paleocene Eocene Thermal Maximum extinction in a greenhouse world.

Science.gov (United States)

Arreguín-Rodríguez, Gabriela J; Thomas, Ellen; D'haenens, Simon; Speijer, Robert P; Alegret, Laia

2018-01-01

The early Eocene greenhouse world was marked by multiple transient hyperthermal events. The most extreme was the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma), linked to the extinction of the globally recognised deep-sea benthic foraminiferal Velasco fauna, which led to the development of early Eocene assemblages. This turnover has been studied at high resolution, but faunal development into the later early Eocene is poorly documented. There is no widely accepted early Eocene equivalent of the Late Cretaceous-Paleocene Velasco fauna, mainly due to the use of different taxonomic concepts. We compiled Ypresian benthic foraminiferal data from 17 middle bathyal-lower abyssal ocean drilling sites in the Pacific, Atlantic and Indian Oceans, in order to characterise early Eocene deep-sea faunas by comparing assemblages across space, paleodepth and time. Nuttallides truempyi, Oridorsalis umbonatus, Bulimina trinitatensis, the Bulimina simplex group, the Anomalinoides spissiformis group, pleurostomellids, uniserial lagenids, stilostomellids and lenticulinids were ubiquitous during the early Eocene (lower-middle Ypresian). Aragonia aragonensis, the Globocassidulina subglobosa group, the Cibicidoides eocaenus group and polymorphinids became ubiquitous during the middle Ypresian. The most abundant early Ypresian taxa were tolerant to stressed or disturbed environments, either by opportunistic behavior (Quadrimorphina profunda, Tappanina selmensis, Siphogenerinoides brevispinosa) and/or the ability to calcify in carbonate-corrosive waters (N. truempyi). Nuttallides truempyi, T. selmensis and other buliminids (Bolivinoides cf. decoratus group, Bulimina virginiana) were markedly abundant during the middle Ypresian. Contrary to the long-lived, highly diverse and equitable Velasco fauna, common and abundant taxa reflect highly perturbed assemblages through the earliest Ypresian, with lower diversity and equitability following the PETM extinction. In contrast, the middle Ypresian

Early Eocene birds from La Borie, southern France

Directory of Open Access Journals (Sweden)

Estelle Bourdon

2016-02-01

Full Text Available The early Eocene locality of La Borie is located in the village of Saint-Papoul, in southern France. These Eocene flu-vio-lacustrine clay deposits have yielded numerous vertebrate remains. Mammalian taxa found in the fossiliferous levels indicate an age near the reference level MP 8–9, which corresponds to the middle Ypresian, early Eocene. Here we provide a detailed description of the avian remains that were preliminarily reported in a recent study of the vertebrate fauna from La Borie. A maxilla, a quadrate, cervical vertebrae, a femur and two tibiotarsi are assigned to the giant ground bird Gastornis parisiensis (Gastornithidae. These new avian remains add to the fossil record of Gastornis, which is known from the late Paleocene to middle Eocene of Europe, early Eocene of Asia and early Eocene of North America. Gastornis parisiensis differs from the North American Gastornis giganteus in several features, including the more ventral position of the narial openings and the slender orbital process of quadrate. Two tibiotarsi and one tarsometatarsus are assigned to a new genus and species of Geranoididae, Galligeranoides boriensis gen. et sp. nov. So far, this family was known only from the early and middle Eocene of North America. The fossils from La Borie constitute the first record of the Geranoididae in Europe. We show that Gastornis coexisted with the Geranoididae in the early Eocene of both Europe (La Borie and North America (Willwood Formation. The presence of Geranoididae and the large flightless bird Gastornis on either side of the present-day North Atlantic provides further evidence that a high-latitude land connection existed between Europe and North America in the early Eocene.

Study of a conceptual nuclear energy center at Green River, Utah: licensing considerations

International Nuclear Information System (INIS)

Dowdle, M.; Russell, R.; Zillman, D.

1982-04-01

This report examines the laws governing the location of a 9-unit nuclear energy center (NEC) near Green River, Utah. The time frame being considered for development of the conceptual NEC is from 1995 to 2013. Accordingly, the report is forced to speculate about some aspects of the plant, its site and its construction. Most of the report examines existing legal requirements for constructing an NEC. Where pertinent, changes in the law are discussed that would affect an NEC that is to be licensed in one or two decades. In general, no insurmountable legal problems exist that would prevent an NEC from being licensed at the Green River location. Several legal requirements pose significant concerns and would have to be faced before an NEC could be built. Among the major legal constraints are radiation protection, regulatory approval of financing, access to water, and local zoning restrictions. Two other constraints that involve legal matters are the wisdom of standardization of the units and the responsibility of the NEC builder to correct socio-economic impacts on the local area

2014 Reassessment of Floodplain Wetland Connections in the Middle Green River, Utah

Energy Technology Data Exchange (ETDEWEB)

LaGory, K. E. [Argonne National Lab. (ANL), Argonne, IL (United States); Walston, L. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Weber, C. C. [Argonne National Lab. (ANL), Argonne, IL (United States)

2016-12-01

This report presents the results of floodplain wetland connection surveys conducted in 2014 at six priority floodplain wetland sites along the middle Green River between Jensen and Ouray, Utah. Surveys were conducted at levee breaches and within channels leading from the breaches to the wetlands (referred to here as connection channels) to characterize the flows needed to connect the river’s main channel with the floodplain wetlands.

A middle Eocene carbon cycle conundrum

NARCIS (Netherlands)

Sluijs, A.; Zeebe, R.; Bijl, P.K.; Bohaty, S.M.

2013-01-01

The Middle Eocene Climatic Optimum (MECO) was an approximately 500,000-year-long episode of widespread ocean-atmosphere warming about 40 million years ago, superimposed on a long-term middle Eocene cooling trend. It was marked by a rise in atmospheric CO2 concentrations, biotic changes and prolonged

Origin and microfossils of the oil shale of the Green River formation of Colorado and Utah

Energy Technology Data Exchange (ETDEWEB)

Bradley, W.H.

1931-01-01

The Green River formation of Colorado and Utah is a series of lakebeds of middle Eocene age that occupy two broad, shallow, simple, structural basins--the Piceance Creek basin in northwestern Colorado and the Uinta basin in northeastern Utah. The ancient lakes served as a basin for the accumulation of tremendous quantities of aquatic organisms. The predominance of microscopic fresh-water algae and protozoa over the remains of land plants, pollens and spores suggests that the greater part of the organic matter was derived from microorganisms that grew in the lakes. The pollens and spores were carried into the lakes by wind. Fish, mollusks, crustaceans, and aquatic insect larvae were also plentiful; and turtles, crocodiles, birds, small camels, and insects may have contributed to the organic matter. The ancient lakes apparently were shallow and had a large area, compared with depth. The abundance of organisms and the decaying organic matter produced a strongly reducing environment. Mechanical and chemical action, such as the mastication and digestion of the organic material by bottom-living organisms, caused disintegration of the original organic matter. When the residue was reduced to a gelatinous condition, it apparently resisted further bacterial decay, and other organisms accidently entombed in the gel were protected from disintegration. An accumulation of inorganic material occurred simultaneously with the disintegration of the organic ooze, and the entire mass became lithified. After most of the oil shale was deposited, the lake reverted nearly to the conditions that prevailed during its early stage, when the marlstone and low-grade oil shale of the basal member were formed. The streams in the vicinity of the lake were rejuvenated and carried great quantities of medium- to coarse-grained sand into the basin and formed a thick layer over the lakebeds.

The onset of the Early Eocene Climatic Optimum at Branch Stream, Clarence River valley, New Zealand

International Nuclear Information System (INIS)

Slotnick, B.S.; Dickens, G.R.; Hollis, C.J.; Crampton, J.S.; Strong, C.P.; Phillips, A.

2015-01-01

We present new lithologic, biostratigraphic and carbon isotope records for a calcareous-rich ∼84m thick, early Eocene, upper continental slope section now exposed along Branch Stream, Marlborough. Decimetre-scale limestone-marl couplets comprise the section. Several marl-rich intervals correspond to carbon isotope excursions (CIEs) representing increased 13 C -depleted carbon fluxes to the ocean. These records are similar to those at nearby Mead Stream, except marl-rich intervals at Branch Stream are thicker with a wider δ 13 C range. Comparison to other sites indicates the section spans ∼53.4-51.6 Ma, the onset of the Early Eocene Climatic Optimum (EECO). The most prominent CIE is correlated with the K/X event (52.9 Ma). Prominent marl-rich intervals resulted from increased fluxes of terrigenous material and associated carbonate dilution. We find multiple warming events marked lowermost EECO, each probably signaling enhanced seasonal precipitation. Branch Stream bulk isotopic records suggest 'differential diagenesis' impacted the sequence during sediment burial. (author).

Integrated stratigraphy of a shallow marine Paleocene-Eocene boundary section, MCBR cores, Maryland (USA)

Science.gov (United States)

Self-Trail, J. M.; Robinson, M. M.; Edwards, L. E.; Powars, D. S.; Wandless, G. A.; Willard, D. A.

2013-12-01

An exceptional Paleocene-Eocene boundary section occurs in a cluster of six short (color from gray to alternating gray and pink also occurs within the CIE transition. These alternating changes in color coincide with cyclic peaks in the carbon isotope and percent calcium carbonate curves, where gray color corresponds to a positive shift in carbon isotope values and to a corresponding increase in percent benthic and planktic foraminifera. The upper third of the Marlboro Clay is barren of all calcareous microfossil material, although the presence of foraminiferal molds and linings proves that deposition occurred in a marine environment. Co-occurrence of the dinoflagellates Apectodinium augustum and Phthanoperidinium crenulatum at the top of the Marlboro Clay suggests that the Marlboro Clay at Mattawoman Creek is truncated. This is corroborated by the absence in the Marlboro of specimens of the calcareous nannofossil Rhomboaster-Discoaster assemblage, which is restricted to early Eocene Zone NP9b. Based on planktic/benthic foraminifera ratios, deposition of sediments at Mattawoman Creek occurred predominantly in an inner neritic environment, at water depths between 25-50 m. Occasional deepening to approximately 75m (middle neritic environment) occurred in the early Eocene, as represented by the basal Marlboro Clay. The planktic/benthic ratio, however, could also be affected by surface productivity and/or river runoff. The gradual shift up-section in core color from gray to alternating gray and red, to dark red, coupled with dissolution of calcareous microfossil assemblages, is possibly secondary and may represent lysocline shoaling in a nearshore environment. This would suggest that lysocline shoaling continued after the CIE and well into the early Eocene.

Fine-scale habitat preference of green sturgeon (Acipenser medirostris) within three spawning locations in the Sacramento River, California

Science.gov (United States)

Wyman, Megan T.; Thomas, Michael J.; McDonald, Richard R.; Hearn, Alexander R.; Battleson, Ryan D.; Chapman, Eric D.; Kinzel, Paul J.; Minear, J. Tobey; Mora, Ethan A.; Nelson, Jonathan M.; Pagel, Matthew D.; Klimley, A. Peter

2018-01-01

Vast sections of the Sacramento River have been listed as critical habitat by the National Marine Fisheries Service for green sturgeon spawning (Acipenser medirostris), yet spawning is known to occur at only a few specific locations. This study reveals the range of physical habitat variables selected by adult green sturgeon during their spawning period. We integrated fine-scale fish positions, physical habitat characteristics, discharge, bathymetry, and simulated velocity and depth using a 2-dimensional hydraulic model (FaSTMECH). The objective was to create habitat suitability curves for depth, velocity, and substrate type within three known spawning locations over two years. An overall cumulative habitat suitability score was calculated that averaged the depth, velocity, and substrate scores over all fish, sites, and years. A weighted usable area (WUA) index was calculated throughout the sampling periods for each of the three sites. Cumulative results indicate that the microhabitat characteristics most preferred by green sturgeon in these three spawning locations were velocities between 1.0-1.1 m/s, depths of 8-9 m, and gravel and sand substrate. This study provides guidance for those who may in the future want to increase spawning habitat for green sturgeon within the Sacramento River.

Eocene squalomorph sharks (Chondrichthyes, Elasmobranchii) from Antarctica

Science.gov (United States)

Engelbrecht, Andrea; Mörs, Thomas; Reguero, Marcelo A.; Kriwet, Jürgen

2017-10-01

Rare remains of predominantly deep-water sharks of the families Hexanchidae, Squalidae, Dalatiidae, Centrophoridae, and Squatinidae are described from the Eocene La Meseta Formation, Seymour Island, Antarctic Peninsula, which has yielded the most abundant chondrichthyan assemblage from the Southern Hemisphere to date. Previously described representatives of Hexanchus sp., Squalus weltoni, Squalus woodburnei, Centrophorus sp., and Squatina sp. are confirmed and dental variations are documented. Although the teeth of Squatina sp. differ from other Palaeogene squatinid species, we refrain from introducing a new species. A new dalatiid taxon, Eodalatias austrinalis gen. et sp. nov. is described. This new material not only increases the diversity of Eocene Antarctic elasmobranchs but also allows assuming that favourable deep-water habitats were available in the Eocene Antarctic Ocean off Antarctica in the Eocene. The occurrences of deep-water inhabitants in shallow, near-coastal waters of the Antarctic Peninsula agrees well with extant distribution patterns.

Eocene squalomorph sharks (Chondrichthyes, Elasmobranchii) from Antarctica.

Science.gov (United States)

Engelbrecht, Andrea; Mörs, Thomas; Reguero, Marcelo A; Kriwet, Jürgen

2017-10-01

Rare remains of predominantly deep-water sharks of the families Hexanchidae, Squalidae, Dalatiidae, Centrophoridae, and Squatinidae are described from the Eocene La Meseta Formation, Seymour Island, Antarctic Peninsula, which has yielded the most abundant chondrichthyan assemblage from the Southern Hemisphere to date. Previously described representatives of Hexanchus sp., Squalus weltoni , Squalus woodburnei , Centrophorus sp., and Squatina sp. are confirmed and dental variations are documented. Although the teeth of Squatina sp. differ from other Palaeogene squatinid species, we refrain from introducing a new species. A new dalatiid taxon, Eodalatias austrinalis gen. et sp. nov. is described. This new material not only increases the diversity of Eocene Antarctic elasmobranchs but also allows assuming that favourable deep-water habitats were available in the Eocene Antarctic Ocean off Antarctica in the Eocene. The occurrences of deep-water inhabitants in shallow, near-coastal waters of the Antarctic Peninsula agrees well with extant distribution patterns.

Testing the ``Wildfire Hypothesis:'' Terrestrial Organic Carbon Burning as the Cause of the Paleocene-Eocene Boundary Carbon Isotope Excursion

Science.gov (United States)

Moore, E. A.; Kurtz, A. C.

2005-12-01

The 3‰ negative carbon isotope excursion (CIE) at the Paleocene-Eocene boundary has generally been attributed to dissociation of seafloor methane hydrates. We are testing the alternative hypothesis that the carbon cycle perturbation resulted from wildfires affecting the extensive peatlands and coal swamps formed in the Paleocene. Accounting for the CIE with terrestrial organic carbon rather than methane requires a significantly larger net release of fossil carbon to the ocean-atmosphere, which may be more consistent with the extreme global warming and ocean acidification characteristic of the Paleocene-Eocene Thermal Maximum (PETM). While other researchers have noted evidence of fires at the Paleocene-Eocene boundary in individual locations, the research presented here is designed to test the "wildfire hypothesis" for the Paleocene-Eocene boundary by examining marine sediments for evidence of a global increase in wildfire activity. Such fires would produce massive amounts of soot, widely distributed by wind and well preserved in marine sediments as refractory black carbon. We expect that global wildfires occurring at the Paleocene-Eocene boundary would produce a peak in black carbon abundance at the PETM horizon. We are using the method of Gelinas et al. (2001) to produce high-resolution concentration profiles of black carbon across the Paleocene-Eocene boundary using seafloor sediments from ODP cores, beginning with the Bass River core from ODP leg 174AX and site 1209 from ODP leg 198. This method involves the chemical and thermal extraction of non-refractory carbon followed by combustion of the residual black carbon and measurement as CO2. Measurement of the δ 13C of the black carbon will put additional constraints on the source of the organic material combusted, and will allow us to determine if this organic material was formed prior to or during the CIE.

Possible role of oceanic heat transport in early Eocene climate

Science.gov (United States)

Sloan, L. C.; Walker, J. C.; Moore, T. C. Jr

1995-01-01

Increased oceanic heat transport has often been cited as a means of maintaining warm high-latitude surface temperatures in many intervals of the geologic past, including the early Eocene. Although the excess amount of oceanic heat transport required by warm high latitude sea surface temperatures can be calculated empirically, determining how additional oceanic heat transport would take place has yet to be accomplished. That the mechanisms of enhanced poleward oceanic heat transport remain undefined in paleoclimate reconstructions is an important point that is often overlooked. Using early Eocene climate as an example, we consider various ways to produce enhanced poleward heat transport and latitudinal energy redistribution of the sign and magnitude required by interpreted early Eocene conditions. Our interpolation of early Eocene paleotemperature data indicate that an approximately 30% increase in poleward heat transport would be required to maintain Eocene high-latitude temperatures. This increased heat transport appears difficult to accomplish by any means of ocean circulation if we use present ocean circulation characteristics to evaluate early Eocene rates. Either oceanic processes were very different from those of the present to produce the early Eocene climate conditions or oceanic heat transport was not the primary cause of that climate. We believe that atmospheric processes, with contributions from other factors, such as clouds, were the most likely primary cause of early Eocene climate.

Regional Hydrology of the Green River-Moab Area, Northwestern Paradox Basin, Utah

OpenAIRE

United States Geological Survey

1982-01-01

The Green River-Moab area encompasses about 7,800 square kilometers or about 25 percent of the Paradox basin. The entire Paradox basin is a part of the Colorado Plateaus that is underlain by a thick sequence of evaporite (salt) beds of Pennsylvanian age. The rock units that underlie the area have been grouped into hydrogeologic units based on their water-transmitting ability. Confining beds consist of evaporite beds of mostly salt, and overlying and underlying thick sequences of rocks with...

Hazard assessment of inorganics to three endangered fish in the Green River, Utah

Science.gov (United States)

Hamilton, S.J.

1995-01-01

Acute toxicity tests were conducted with three life stages of Colorado squawfish (Ptychocheilus lucius), razorback sucker (Xyrauchen texanus), and bonytail (Gila elegans) in a reconstituted water quality simulating the middle part of the Green River of Utah. Tests were conducted with boron, lithium, selenate, selenite, uranium, vanadium, and zinc. The overall rank order of toxicity to all species and life stages combined from most to least toxic was vanadium = zinc > selenite > lithium = uranium > selenate > boron. There was no difference between the three species in their sensitivity to the seven inorganics based on a rank-order evaluation at the species level. Colorado squawfish were 2-5 times more sensitive to selenate and selenite at the swimup life stage than older stages, whereas razorback suckers displayed equal sensitivity among life stages. Bonytail exhibited equal sensitivity to selenite, but were five times more sensitive to selenate at the swimup life stage than the older stages. Comparison of 96-hr LC50 values with a limited number of environmental water concentrations in Ashley Creek, Utah, which receives irrigation drainwater, revealed moderate hazard ratios for boron, selenate, selenite, and zinc, low hazard ratios for uranium and vanadium, but unknown ratios for lithium. These inorganic contaminants in drainwaters may adversely affect endangered fish in the Green River.

An occurrence of the protocetid whale "Eocetus" wardii in the middle Eocene Piney Point Formation of Virginia

Science.gov (United States)

Weems, R.E.; Edwards, L.E.; Osborne, J.E.; Alford, A.A.

2011-01-01

Two protocetid whale vertebrae, here referred to “Eocetus” wardii, have been recovered from the riverbed of the Pamunkey River in east-central Virginia. Neither bone was found in situ, but both were found with lumps of lithified matrix cemented to their surfaces. Most of this matrix was removed and processed for microfossils. Specimens of dinoflagellates were successfully recovered and this flora clearly demonstrates that both vertebrae came from the middle Eocene Piney Point Formation, which crops out above and below river level in the area where the bones were discovered. These vertebrae are the oldest whale remains reported from Virginia and are as old as any cetacean remains known from the western hemisphere.

Regional hydrology of the Green River-Moab area, northwestern Paradox Basin, Utah

International Nuclear Information System (INIS)

Rush, F.E.; Whitfield, M.S.; Hart, I.M.

1982-12-01

The Green River-Moab area encompasses about 7800 square kilometers or about 25% of the Paradox basin. The entire Paradox basin is a part of the Colorado Plateaus that is underlain by a thick sequence of evaporite (salt) beds of Pennsylvanian age. The rock units that underlie the area have been grouped into hydrogeologic units based on their water-transmitting ability. Confining beds consist of evaporite beds of mostly salt, and overlying and underlying thick sequences of rocks with minimal permeability; above and below these confining beds are aquifers. The upper Mesozoic sandstone aquifer, probably is the most permeable hydrogeologic unit of the area and is the subject of this investigation. The principal component of groundwater outflow from this aquifer probably is subsurface flow to regional streams (the Green and Colorado Rivers) and is about 100 million cubic meters per year. All other components of outflow are relatively small. The average annual recharge to the aquifer is about 130 million cubic meters, of which about 20 million cubic meters is from local precipitation. For the lower aquifer, all recharge and discharge probably is by subsurface flow and was not estimated. The aquifers are generally isolated from the evaporite beds by the bounding confining beds; as a result, most ground water has little if any contact with the evaporites. Brines are present in the confining beds, but solution of beds of salt probably is very slow in most parts of the area. No brine discharges have been identified

Discovery of Eocene adakites in Primor'e

Science.gov (United States)

Chashchin, A. A.; Nechaev, V. P.; Nechaeva, E. V.; Blokhin, M. G.

2011-06-01

This paper presents the first results of petrochemical and geochemical studies (by the ICP-MS technique) of adakites comprising a small extrusive body in the Ilistaya River basin (West Primor'e). Based on the data of radioisotopic dating (K-Ar method), the age of adakites corresponds to the Middle Eocene (45.52 ± 1.1 Ma). In terms of the content of most microelements and the value of the Sr/Y ratio, the discussed rocks are close to Paleogene adakites from northwest China, the Kitakami massif in Japan, and the northwestern margin of North America; these rocks are attributed to gaps in the subducted plate (slab windows). Additionally, the adakites found in Primor'e significantly differ from adakite-like rocks found in Tibet formed during melting of bottoms of the superthickened continental crust. Thus, this discovery proves the hypothesis about formation of slab windows at the Paleogene stage of the region's evolution.

Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Green River, Utah. Revision 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (phase 1) and the Ground Water Project (phase 2). For the UMTRA Project site located near Green River, Utah, the Surface Project cleanup occurred from 1988 to 1989. The tailings and radioactively contaminated soils and materials were removed from their original locations and placed into a disposal cell on the site. The disposal cell is designed to minimize radiation emissions and minimize further contamination of ground water beneath the site. The UMTRA Project`s second phase, the Ground Water Project, evaluates the nature and extent of ground water contamination resulting from uranium processing and determines a strategy for ground water compliance with the Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. For the Green River site, the risk assessment helps determine whether human health risks result from exposure to ground water contaminated by uranium processing. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Green River site. What follows is an evaluation of current and possible future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will be used to determine what is necessary, if anything, to protect human health and the environment while complying with EPA standards.

Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Green River, Utah. Revision 1

International Nuclear Information System (INIS)

1995-09-01

The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (phase 1) and the Ground Water Project (phase 2). For the UMTRA Project site located near Green River, Utah, the Surface Project cleanup occurred from 1988 to 1989. The tailings and radioactively contaminated soils and materials were removed from their original locations and placed into a disposal cell on the site. The disposal cell is designed to minimize radiation emissions and minimize further contamination of ground water beneath the site. The UMTRA Project's second phase, the Ground Water Project, evaluates the nature and extent of ground water contamination resulting from uranium processing and determines a strategy for ground water compliance with the Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. For the Green River site, the risk assessment helps determine whether human health risks result from exposure to ground water contaminated by uranium processing. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Green River site. What follows is an evaluation of current and possible future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will be used to determine what is necessary, if anything, to protect human health and the environment while complying with EPA standards

Detailed north-south cross section showing environments of deposition, organic richness, and thermal maturities of lower Tertiary rocks in the Uinta Basin, Utah

Science.gov (United States)

Johnson, Ronald C.

2014-01-01

The Uinta Basin of northeast Utah has produced large amounts of hydrocarbons from lower Tertiary strata since the 1960s. Recent advances in drilling technologies, in particular the development of efficient methods to drill and hydraulically fracture horizontal wells, has spurred renewed interest in producing hydrocarbons from unconventional low-permeability dolomite and shale reservoirs in the lacustrine, Eocene Green River Formation. The Eocene Green River Formation was deposited in Lake Uinta, a long-lived saline lake that occupied the Uinta Basin, the Piceance Basin to the east, and the intervening Douglas Creek arch. The focus of recent drilling activity has been the informal Uteland Butte member of the Green River Formation and to a much lesser extent the overlying R-0 oil shale zone of the Green River Formation. Initial production rates ranging from 500 to 1,500 barrels of oil equivalent per day have been reported from the Uteland Butte member from horizontal well logs that are as long as 4,000 feet (ft);. The cross section presented here extends northward from outcrop on the southern margin of the basin into the basin’s deep trough, located just south of the Uinta Mountains, and transects the area where this unconventional oil play is developing. The Monument Butte field, which is one of the fields located along this line of section, has produced hydrocarbons from conventional sandstone reservoirs in the lower part of the Green River Formation and underlying Wasatch Formation since 1981. A major fluvial-deltaic system entered Lake Uinta from the south, and this new line of section is ideal for studying the effect of the sediments delivered by this drainage on hydrocarbon reservoirs in the Green River Formation. The cross section also transects the Greater Altamont-Bluebell field in the deepest part of the basin, where hydrocarbons have been produced from fractured, highly overpressured marginal lacustrine and fluvial reservoirs in the Green River, Wasatch

Oxygen isotopes of marine mollusc shells record Eocene elevation change in the Pyrenees

Science.gov (United States)

Huyghe, Damien; Mouthereau, Frédéric; Emmanuel, Laurent

2012-09-01

Constraining paleoaltimetry of collisional orogens is critical to understand the dynamics of topographic evolution and climate/tectonics retroactions. Here, we use oxygen stable-isotope record on oyster shells, preserved in marine foreland deposits, to examine the past elevation of the Pyrenees during the Eocene. Our approach is based on the comparison with the Paris basin, an intracratonic basin not influenced by orogenic growth. The finding of a shift of 1.5‰ between 49 and 41 Ma, indicating more negative δ18Oc in the south Pyrenean foreland, is interpreted to reflect the inflow of river water sourced from higher elevation in the Pyrenees. To test this and provide paleoelevation estimate, we adopt a morphologic-hydrological model accounting for the hypsometry of drainage basin. Our best fitting model shows that the Pyrenees rose up to 2000 m. This indicates that the Pyrenees reached high elevation in the Eocene, thus providing new critical constraints on their long-term orogenic development. δ18O of marine mollusc shells are proved potentially attractive for paleoelevation studies, especially for mountain belts where elevated continental surfaces have not been preserved.

Humidity estimate for the middle Eocene Arctic rain forest

Science.gov (United States)

Jahren, A. Hope; Silveira Lobo Sternberg, Leonel

2003-05-01

The exquisite preservation of fossilized Metasequoia trees that grew near 80°N latitude during the middle Eocene (ca. 45 Ma) in Nunavut, Canada, allowed for δD and δ18O analyses of cellulose, techniques previously restricted to wood <30,000 yr old. From the isotopic results, we determined that the middle Eocene Arctic atmosphere contained ˜2× the water found in the region's atmosphere today. This water vapor contributed to a middle Eocene greenhouse effect that insulated the polar region during dark polar winters.

http://dx.doi.org/10.4314/jae.v18i1.4 Adoption of Green River Project ...

African Journals Online (AJOL)

PROF. MADUKWE

Adoption of Green River Project Fish Farming Technologies by Farmers in Niger. Delta Region of ... Majority of the respondents adopted fish farm management ... is a decision of full use of an innovation as the best course of action available. ... It is also important to develop sustainable financing option, use well trained and.

LEAK AND GAS PERMEABILITY TESTING DURING SOIL-GAS SAMPLING AT HAL'S CHEVRON LUST SITE IN GREEN RIVER, UTAH

Science.gov (United States)

The results of gas permeability and leak testing during active soil-gas sampling at Hal’s Chevron LUST Site in Green River, Utah are presented. This study was conducted to support development of a passive soil-gas sampling method. Gas mixtures containing helium and methane were...

[Proceedings of the 5th Symposium on Mesozoic and Cenozoic Decapod Crustaceans, Krakow, Poland, 2013: A tribute to Pál Mihály Müller / R.H.B. Fraaije, M. Hyžný, J.W.M. Jagt, M. Krobicki & B.W.M. van Bakel (eds.)]: Neozanthopsis americana (Decapoda, Brachyura, Carpilioidea) from the Middle Eocene Cane River Formation of Louisiana, USA, and associated teleost otoliths

NARCIS (Netherlands)

Schweitzer, C.E.; Feldmann, R.M.; Stringer, G.L.

2014-01-01

A large collection of Neozanthopsis americana (Rathbun, 1928) from the Middle Eocene (Lutetian) Cane River Formation in Louisiana, USA, represents the first opportunity to describe the species in detail. Detailed analysis of associated teleost otoliths and other vertebrate remains documents a

Study of a conceptual nuclear energy center at Green River, Utah: regional considerations

International Nuclear Information System (INIS)

1982-01-01

This document constitutes one segment of a feasibility study investigating the ramifications of constructing a nuclear energy center in an arid and remote Western region. This phase of the study discusses regional considerations involved in nuclear energy center development at Green River, Utah. Regional support for NEC development is assessed. In addition, possible regulatory constraints to NEC development are identified and analyzed. Possible resource allocation shortages resulting from NEC development are also considered. A comparison with a similar study on NEC development in the Southeastern United States is also included

The Paleocene and lower Eocene pollen flora of Guyana

NARCIS (Netherlands)

Leidelmeyer, P.

1966-01-01

A description is given of a Paleocene and Lower Eocene pollen flora of two bore-holes in Guana. Some new species are described and some remarks are made on their stratigraphical significance. Pollen diagrams are presented, one probably representing the entire Paleocene and a part of the Eocene.

Potential effects of elevated base flow and midsummer spike flow experiments on riparian vegetation along the Green River

Science.gov (United States)

Friedman, Jonathan M.

2018-01-01

The Upper Colorado River Endangered Fish Recovery Program has requested experimental flow releases from Flaming Gorge Dam for (1) elevated summer base flows to promote larval endangered Colorado pikeminnow, and (2) midsummer spike flows to disadvantage spawning invasive smallmouth bass. This white paper explores the effects of these proposed flow modifications on riparian vegetation and sediment deposition downstream along the Green River. Although modest in magnitude, the elevated base flows and possible associated reductions in magnitude or duration of peak flows would exacerbate a long-term trend of flow stabilization on the Green River that is already leading to proliferation of vegetation including invasive tamarisk along the channel and associated sediment deposition, channel narrowing and channel simplification. Midsummer spike flows could promote establishment of late-flowering plants like tamarisk. Because channel narrowing and simplification threaten persistence and quality of backwater and side channel features needed by endangered fish, the proposed flow modifications could lead to degradation of fish habitat. Channel narrowing and vegetation encroachment could be countered by increases in peak flows or reductions in base flows in some years and by prescription of rapid flow declines following midsummer spike flows. These strategies for reducing vegetation encroachment would need to be balanced with flow

Podargiform affinities of the enigmatic Fluvioviridavis platyrhamphus and the early diversification of Strisores ("Caprimulgiformes" + Apodiformes).

Science.gov (United States)

Nesbitt, Sterling J; Ksepka, Daniel T; Clarke, Julia A

2011-01-01

The early Eocene Green River Formation avifauna preserves exceptional exemplars of the earliest unambiguous stem representatives of many extant avian clades. We identify the basal-most member of Podargiformes (extant and fossil stem lineage frogmouths) based on a new specimen of Fluvioviridavis platyrhamphus, a unique neoavian bird from the Fossil Butte Member of the Green River Formation of Wyoming. Extant frogmouths (Podargidae) comprise approximately 13 nocturnal species with an exclusively Australasian distribution. The new specimen was included in a combined phylogenetic analysis of morphological (osteology and soft tissue) and molecular sequence (cytochrome b, c-myc exon 3, and RAG) data sampling species-level taxa from both extant and extinct members of Steatornithidae, Podargidae, Caprimulgidae, Nyctibiidae, Aegothelidae, and Apodiformes ( = Strisores). New data from F. platyrhamphus help resolve phylogenetic relationships within Strisores, supporting placement of F. platyrhamphus and the European fossil form Masillapodargus longipes as basal parts of Podargiformes and also supporting a sister taxon relationship between Podargiformes and Steatornithiformes (oilbirds) within Strisores. This relationship is recovered only when fossil taxa are included, reaffirming the potential impact of stem fossil taxa on inferences of phylogenetic relationships. The well-preserved mandible and palate of the new specimen demonstrate that many of the unique characteristics of the skull that characterize the crown frogmouth clade Podargidae arose early in the evolutionary history of the clade, over 50 million years ago. Comparisons with the new specimen also indicate that Eurofluvioviridavis and Fluvioviridavis are not closely related. Together with the European fossil frogmouth Masillapodargus, Fluvioviridavis shows that Podargiformes had a much wider geographic distribution in the past, whereas extant species are restricted to Australasia. The Eocene record of Strisores

Podargiform affinities of the enigmatic Fluvioviridavis platyrhamphus and the early diversification of Strisores ("Caprimulgiformes" + Apodiformes.

Directory of Open Access Journals (Sweden)

Sterling J Nesbitt

Full Text Available The early Eocene Green River Formation avifauna preserves exceptional exemplars of the earliest unambiguous stem representatives of many extant avian clades. We identify the basal-most member of Podargiformes (extant and fossil stem lineage frogmouths based on a new specimen of Fluvioviridavis platyrhamphus, a unique neoavian bird from the Fossil Butte Member of the Green River Formation of Wyoming. Extant frogmouths (Podargidae comprise approximately 13 nocturnal species with an exclusively Australasian distribution.The new specimen was included in a combined phylogenetic analysis of morphological (osteology and soft tissue and molecular sequence (cytochrome b, c-myc exon 3, and RAG data sampling species-level taxa from both extant and extinct members of Steatornithidae, Podargidae, Caprimulgidae, Nyctibiidae, Aegothelidae, and Apodiformes ( = Strisores. New data from F. platyrhamphus help resolve phylogenetic relationships within Strisores, supporting placement of F. platyrhamphus and the European fossil form Masillapodargus longipes as basal parts of Podargiformes and also supporting a sister taxon relationship between Podargiformes and Steatornithiformes (oilbirds within Strisores. This relationship is recovered only when fossil taxa are included, reaffirming the potential impact of stem fossil taxa on inferences of phylogenetic relationships. The well-preserved mandible and palate of the new specimen demonstrate that many of the unique characteristics of the skull that characterize the crown frogmouth clade Podargidae arose early in the evolutionary history of the clade, over 50 million years ago. Comparisons with the new specimen also indicate that Eurofluvioviridavis and Fluvioviridavis are not closely related.Together with the European fossil frogmouth Masillapodargus, Fluvioviridavis shows that Podargiformes had a much wider geographic distribution in the past, whereas extant species are restricted to Australasia. The Eocene record

Podargiform Affinities of the Enigmatic Fluvioviridavis platyrhamphus and the Early Diversification of Strisores (“Caprimulgiformes” + Apodiformes)

Science.gov (United States)

Nesbitt, Sterling J.; Ksepka, Daniel T.; Clarke, Julia A.

2011-01-01

Background The early Eocene Green River Formation avifauna preserves exceptional exemplars of the earliest unambiguous stem representatives of many extant avian clades. We identify the basal-most member of Podargiformes (extant and fossil stem lineage frogmouths) based on a new specimen of Fluvioviridavis platyrhamphus, a unique neoavian bird from the Fossil Butte Member of the Green River Formation of Wyoming. Extant frogmouths (Podargidae) comprise approximately 13 nocturnal species with an exclusively Australasian distribution. Methodology/Principal Findings The new specimen was included in a combined phylogenetic analysis of morphological (osteology and soft tissue) and molecular sequence (cytochrome b, c-myc exon 3, and RAG) data sampling species-level taxa from both extant and extinct members of Steatornithidae, Podargidae, Caprimulgidae, Nyctibiidae, Aegothelidae, and Apodiformes ( = Strisores). New data from F. platyrhamphus help resolve phylogenetic relationships within Strisores, supporting placement of F. platyrhamphus and the European fossil form Masillapodargus longipes as basal parts of Podargiformes and also supporting a sister taxon relationship between Podargiformes and Steatornithiformes (oilbirds) within Strisores. This relationship is recovered only when fossil taxa are included, reaffirming the potential impact of stem fossil taxa on inferences of phylogenetic relationships. The well-preserved mandible and palate of the new specimen demonstrate that many of the unique characteristics of the skull that characterize the crown frogmouth clade Podargidae arose early in the evolutionary history of the clade, over 50 million years ago. Comparisons with the new specimen also indicate that Eurofluvioviridavis and Fluvioviridavis are not closely related. Conclusions/Significance Together with the European fossil frogmouth Masillapodargus, Fluvioviridavis shows that Podargiformes had a much wider geographic distribution in the past, whereas extant

Analysis of some aromatic hydrocarbons in a benzene-soluble bitumen from Green River shale

Energy Technology Data Exchange (ETDEWEB)

Anders, D.E.; Doolittle, F.G.; Robinson, W.E.

1973-01-01

The hydrocarbon content of an aromatic fraction, isolated from the bitumen of Green River shale, was studied by mass spectrometry, infra-red spectrometry, gas chromatography and a dehydrogenation technique. The hydrocarbon types and their distribution in this aromatic fraction, as determined by mass spectrometry, are presented. The carbon-number range, empirical formulas and quantity of each compound in the major types are reported. Mass spectra of several compounds and homologous mixtures of compounds isolated from the aromatic fraction are also given.

First record of eocene bony fishes and crocodyliforms from Canada's Western Arctic.

Science.gov (United States)

Eberle, Jaelyn J; Gottfried, Michael D; Hutchison, J Howard; Brochu, Christopher A

2014-01-01

Discovery of Eocene non-marine vertebrates, including crocodylians, turtles, bony fishes, and mammals in Canada's High Arctic was a critical paleontological contribution of the last century because it indicated that this region of the Arctic had been mild, temperate, and ice-free during the early - middle Eocene (∼53-50 Ma), despite being well above the Arctic Circle. To date, these discoveries have been restricted to Canada's easternmost Arctic - Ellesmere and Axel Heiberg Islands (Nunavut). Although temporally correlative strata crop out over 1,000 km west, on Canada's westernmost Arctic Island - Banks Island, Northwest Territories - they have been interpreted as predominantly marine. We document the first Eocene bony fish and crocodyliform fossils from Banks Island. We describe fossils of bony fishes, including lepisosteid (Atractosteus), esocid (pike), and amiid, and a crocodyliform, from lower - middle Eocene strata of the Cyclic Member, Eureka Sound Formation within Aulavik National Park (∼76°N. paleolat.). Palynology suggests the sediments are late early to middle Eocene in age, and likely spanned the Early Eocene Climatic Optimum (EECO). These fossils extend the geographic range of Eocene Arctic lepisosteids, esocids, amiids, and crocodyliforms west by approximately 40° of longitude or ∼1100 km. The low diversity bony fish fauna, at least at the family level, is essentially identical on Ellesmere and Banks Islands, suggesting a pan-High Arctic bony fish fauna of relatively basal groups around the margin of the Eocene Arctic Ocean. From a paleoclimatic perspective, presence of a crocodyliform, gar and amiid fishes on northern Banks provides further evidence that mild, year-round temperatures extended across the Canadian Arctic during early - middle Eocene time. Additionally, the Banks Island crocodyliform is consistent with the phylogenetic hypothesis of a Paleogene divergence time between the two extant alligatorid lineages Alligator

Hinterland drainage closure and lake formation in response to middle Eocene Farallon slab removal, Nevada, U.S.A.

Science.gov (United States)

Smith, M. Elliot; Cassel, Elizabeth J.; Jicha, Brian R.; Singer, Brad S.; Canada, Andrew S.

2017-12-01

Hinterland basins can accumulate high resolution archives of orogenic processes and continental climate, but are challenging to reconstruct due to tectonic overprinting and the inherent complexity of their lithofacies assemblages. The Cordilleran hinterland of northeast Nevada has been interpreted to have overlain a flattened Farallon slab from the Late Cretaceous to Eocene. Slab removal and advection of asthenospheric mantle beneath Nevada have been invoked to explain a southwestward migrating wave of Eocene to Oligocene volcanism and proposed as a driver for topographic uplift. However, the timing of slab removal and possible subsequent delamination of North American lithospheric mantle can only ambiguously be related to the surface record. Subsequent Neogene extension and basin filling has complicated the correlation and interpretation of strata that record these events. Here we apply single crystal sanidine 40Ar/39Ar geochronology to 26 ash beds in northeast Nevada to reconstruct Paleogene geographic and hydrologic evolution. We use these ages and legacy geochronology to compare lithofacies and isotope proxy records of meteoric waters to regional tectonics and global climate, and assess competing tectonic interpretations for lake basin formation. Lakes formed locally prior to ca. 48.7 Ma in northeast Nevada, coeval with foreland lakes of the Green River Formation. The most expansive phase of lacustrine deposition resulted in onlap onto locally derived fluvial deposits and folded Paleozoic bedrock, and occurred between ca. 43.4 and ca. 40.8 Ma. Elko Formation strata exhibit a basin-wide transition from fluvial-lacustrine to fluctuating profundal lithofacies at ca. 42.7 Ma, suggesting a shift towards regional hydrologic closure. The stromatolitic upper Elko Formation is intercalated with ash fall tuffs and several partially welded to unwelded ignimbrites from increasingly proximal volcanism. Elko Formation deposition ended by ca. 40.4 Ma. 40Ar/39Ar ages for seven

Late Eocene rings around the earth

Science.gov (United States)

King, E. A.

1980-01-01

The suggestion of O'Keefe (1980) that the terminal Eocene event was caused by rings of tektite material encircling the earth is discussed. It is argued that the assumption that the tektites are of lunar volcanic origin is unwarranted and contrary to existing data, including the lack of lunar rocks of suitable composition, the lack of lunar rocks of the correct age, the lack of evidence that the North American tektites fell throughout a sedimentary rock column of a few million years, and the nondetection of a tektite with a measurable cosmic ray exposure age. Alternatively, it is suggested that the terminal Eocene event may be associated with volcanic ash, air-fall tuff and bentonite in the late Eocene. O'Keefe replies that the hypothesis of the terrestrial origin of the tektites conflicts with the laws of physics, for example in the glass structure and shaping of the tektites. Furthermore, evidence is cited for lunar rocks of the proper major-element composition and ages, and it is noted that the proposed solar Poynting-Robertson effect would account for the particle fall distributions and cosmic ray ages.

Dispersal of thermophilic beetles across the intercontinental Arctic forest belt during the early Eocene.

Science.gov (United States)

Brunke, Adam J; Chatzimanolis, Stylianos; Metscher, Brian D; Wolf-Schwenninger, Karin; Solodovnikov, Alexey

2017-10-11

Massive biotic change occurred during the Eocene as the climate shifted from warm and equable to seasonal and latitudinally stratified. Mild winter temperatures across Arctic intercontinental land bridges permitted dispersal of frost-intolerant groups until the Eocene-Oligocene boundary, while trans-Arctic dispersal in thermophilic groups may have been limited to the early Eocene, especially during short-lived hyperthermals. Some of these lineages are now disjunct between continents of the northern hemisphere. Although Eocene climate change may have been one of the most important drivers of these ancient patterns in modern animal and plant distributions, its particular events are rarely implicated or correlated with group-specific climatic requirements. Here we explored the climatic and geological drivers of a particularly striking Neotropical-Oriental disjunct distribution in the rove beetle Bolitogyrus, a suspected Eocene relict. We integrated evidence from Eocene fossils, distributional and climate data, paleoclimate, paleogeography, and phylogenetic divergence dating to show that intercontinental dispersal of Bolitogyrus ceased in the early Eocene, consistent with the termination of conditions required by thermophilic lineages. These results provide new insight into the poorly known and short-lived Arctic forest community of the Early Eocene and its surviving lineages.

Scaled biotic disruption during early Eocene global warming events

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S. J. Gibbs

2012-11-01

Full Text Available Late Paleocene and early Eocene hyperthermals are transient warming events associated with massive perturbations of the global carbon cycle, and are considered partial analogues for current anthropogenic climate change. Because the magnitude of carbon release varied between the events, they are natural experiments ideal for exploring the relationship between carbon cycle perturbations, climate change and biotic response. Here we quantify marine biotic variability through three million years of the early Eocene that include five hyperthermals, utilizing a method that allows us to integrate the records of different plankton groups through scenarios ranging from background to major extinction events. Our long time-series calcareous nannoplankton record indicates a scaling of biotic disruption to climate change associated with the amount of carbon released during the various hyperthermals. Critically, only the three largest hyperthermals, the Paleocene–Eocene Thermal Maximum (PETM, Eocene Thermal Maximum 2 (ETM2 and the I1 event, show above-background variance, suggesting that the magnitude of carbon input and associated climate change needs to surpass a threshold value to cause significant biotic disruption.

Lygistorrhinidae (Diptera: Bibionomorpha: Sciaroidea in early Eocene Cambay amber

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Frauke Stebner

2017-05-01

Full Text Available One new genus and three new species of Lygistorrhinidae in early Eocene Cambay amber from India are described, which significantly increases our knowledge about this group in the Eocene. Lygistorrhina indica n. sp. is the oldest fossil known from this extant genus. Indorrhina sahnii n. gen. et sp. shows morphological similarities to each of the two extant genera Lygistorrhina and Asiorrhina. Palaeognoriste orientale is the third species known from a group that has only been recorded from Eocene Baltic amber before. The latter finding reveals faunal links between Cambay amber and the probably slightly younger Baltic amber, adding further evidence that faunal exchange between Europe/Asia and India took place before the formation of Cambay amber.

Lygistorrhinidae (Diptera: Bibionomorpha: Sciaroidea) in early Eocene Cambay amber.

Science.gov (United States)

Stebner, Frauke; Singh, Hukam; Rust, Jes; Grimaldi, David A

2017-01-01

One new genus and three new species of Lygistorrhinidae in early Eocene Cambay amber from India are described, which significantly increases our knowledge about this group in the Eocene. Lygistorrhina indica n. sp. is the oldest fossil known from this extant genus. Indorrhina sahnii n. gen. et sp. shows morphological similarities to each of the two extant genera Lygistorrhina and Asiorrhina . Palaeognoriste orientale is the third species known from a group that has only been recorded from Eocene Baltic amber before. The latter finding reveals faunal links between Cambay amber and the probably slightly younger Baltic amber, adding further evidence that faunal exchange between Europe/Asia and India took place before the formation of Cambay amber.

Mesozoic to Eocene ductile deformation of western Central Iran: From Cimmerian collisional orogeny to Eocene exhumation

Science.gov (United States)

Kargaranbafghi, Fariba; Neubauer, Franz; Genser, Johann; Faghih, Ali; Kusky, Timothy

2012-09-01

To advance our understanding of the Mesozoic to Eocene tectonics and kinematics of basement units exposed in the south-western Central Iran plateau, this paper presents new structural and thermochronological data from the Chapedony metamorphic core complex and hangingwall units, particularly from the Posht-e-Badam complex. The overall Paleogene structural characteristics of the area are related to an oblique convergent zone. The Saghand area represents part of a deformation zone between the Arabian and Eurasian plates, and can be interpreted to result from the Central Iran intracontinental deformation acting as a weak zone during Mesozoic to Paleogene times. Field and microstructural evidence reveal that the metamorphic and igneous rocks suffered a ductile shear deformation including mylonitization at the hangingwall boundary of the Eocene Chapedony metamorphic core complex. Comparison of deformation features in the mylonites and other structural features within the footwall unit leads to the conclusion that the mylonites were formed in a subhorizontal shear zone by NE-SW stretching during Middle to Late Eocene extensional tectonics. The Chapedony metamorphic core complex is characterized by amphibolite-facies metamorphism and development of S and S-L tectonic fabrics. The Posht-e-Badam complex was deformed by two stages during Cimmerian tectonic processes forming the Paleo-Tethyan suture.

Ultimate Eocene (Priabonian) Chondrichthyans (Holocephali, Elasmobranchii) of Antarctica.

Science.gov (United States)

Kriwet, Jürgen; Engelbrecht, Andrea; Mörs, Thomas; Reguero, Marcelo; Pfaff, Cathrin

2016-01-01

The Eocene La Meseta Formation on Seymour Island, Antarctic Peninsula, is known for its remarkable wealth of fossil remains of chondrichthyans and teleosts. Chondrichthyans seemingly were dominant elements in the Antarctic Paleogene fish fauna, but decreased in abundance from middle to late Eocene, during which time remains of bony fishes increase. This decline of chondrichthyans at the end of the Eocene generally is related to sudden cooling of seawater, reduction in shelf area, and increasing shelf depth due to the onset of the Antarctic thermal isolation. The last chondrichthyan records known so far include a chimeroid tooth plate from TELM 6 (Lutetian) and a single pristiophorid rostral spine from TELM 7 (Priabonian). Here, we present new chondrichthyan records of Squalus , Squatina , Pristiophorus , Striatolamia , Palaeohypotodus , Carcharocles , and Ischyodus from the upper parts of TELM 7 (Priabonian), including the first record of Carcharocles sokolovi from Antarctica. This assemblage suggests that chondrichthyans persisted much longer in Antarctic waters despite rather cool sea surface temperatures of approximately 5°C. The final disappearance of chondrichthyans at the Eocene-Oligocene boundary concurs with abrupt ice sheet formation in Antarctica. Diversity patterns of chondrichthyans throughout the La Meseta Formation appear to be related to climatic conditions rather than plate tectonics.

Lower Eocene on Majevica north of Tuzla (NE Bosnia

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Jernej Pavšič

2005-06-01

Full Text Available In Lower Eocene marlstones on Mt. Majevica in northeastern Bosnia species Nummulites atacicus and N. robustus were determined, the latter first found on the Balkan Peninsula.In the beds occur next to Paleogene many redeposited Cretaceous nannoplankton species, an indication of the exposure of Cretaceous beds in Lower Eocene in the investigated area.

Proposed ground water protection strategy for the Uranium Mill Tailings Site at Green River, Utah. Final report

International Nuclear Information System (INIS)

1994-11-01

This document presents the US DOE water resources protection strategy for the Green River, Utah mill tailings disposal site. The modifications in the original plan are based on new information, including ground water quality data collected after remedial action was completed, and on a revised assessment of disposal cell design features, surface conditions, and site hydrogeology. All aspects are discussed in this report

Apatite fission-track evidence for regional exhumation in the subtropical Eocene, block faulting, and localized fluid flow in east-central Alaska

Science.gov (United States)

Dusel-Bacon, Cynthia; Bacon, Charles R.; O'Sullivan, Paul B.; Day, Warren C.

2016-01-01

The origin and antiquity of the subdued topography of the Yukon–Tanana Upland (YTU), the physiographic province between the Denali and Tintina faults, are unresolved questions in the geologic history of interior Alaska and adjacent Yukon. We present apatite fission-track (AFT) results for 33 samples from the 2300 km2 western Fortymile district in the YTU in Alaska and propose an exhumation model that is consistent with preservation of volcanic rocks in valleys that requires base level stability of several drainages since latest Cretaceous–Paleocene time. AFT thermochronology indicates widespread cooling below ∼110 °C at ∼56–47 Ma (early Eocene) and ∼44–36 Ma (middle Eocene). Samples with ∼33–27, ∼19, and ∼10 Ma AFT ages, obtained near a major northeast-trending fault zone, apparently reflect hydrothermal fluid flow. Uplift and erosion following ∼107 Ma magmatism exposed plutonic rocks to different extents in various crustal blocks by latest Cretaceous time. We interpret the Eocene AFT ages to suggest that higher elevations were eroded during the Paleogene subtropical climate of the subarctic, while base level remained essentially stable. Tertiary basins outboard of the YTU contain sediment that may account for the required >2 km of removed overburden that was not carried to the sea by the ancestral Yukon River system. We consider a climate driven explanation for the Eocene AFT ages to be most consistent with geologic constraints in concert with block faulting related to translation on the Denali and Tintina faults resulting from oblique subduction along the southern margin of Alaska.

Revision of Eocene Antarctic carpet sharks (Elasmobranchii, Orectolobiformes) from Seymour Island, Antarctic Peninsula.

Science.gov (United States)

Engelbrecht, Andrea; Mörs, Thomas; Reguero, Marcelo A; Kriwet, Jürgen

2017-01-01

Seymour Island, Antarctic Peninsula, was once called the 'Rosetta Stone' of Southern Hemisphere palaeobiology, because this small island provides the most complete and richly fossiliferous Palaeogene sequence in Antarctica. Among fossil marine vertebrate remains, chondrichthyans seemingly were dominant elements in the Eocene Antarctic fish fauna. The fossiliferous sediments on Seymour Island are from the La Meseta Formation, which was originally divided into seven stratigraphical levels, TELMs 1-7 (acronym for Tertiary Eocene La Meseta) ranging from the upper Ypresian (early Eocene) to the late Priabonian (late Eocene). Bulk sampling of unconsolidated sediments from TELMs 5 and 6, which are Ypresian (early Eocene) and Lutetian (middle Eocene) in age, respectively, yielded very rich and diverse chondrichthyan assemblages including over 40 teeth of carpet sharks representing two new taxa, Notoramphoscyllium woodwardi gen. et sp. nov. and Ceolometlaouia pannucae gen. et sp. nov. Two additional teeth from TELM 5 represent two different taxa that cannot be assigned to any specific taxon and thus are left in open nomenclature. The new material not only increases the diversity of Eocene Antarctic selachian faunas but also allows two previous orectolobiform records to be re-evaluated. Accordingly, Stegostoma cf. faciatum is synonymized with Notoramphoscyllium woodwardi gen. et sp. nov., whereas Pseudoginglymostoma cf. brevicaudatum represents a nomen dubium . The two new taxa, and probably the additional two unidentified taxa, are interpreted as permanent residents, which most likely were endemic to Antarctic waters during the Eocene and adapted to shallow and estuarine environments.

Eocene sea temperatures for the mid-latitude southwest Pacific from Mg/Ca ratios in planktonic and benthic foraminifera

Science.gov (United States)

Creech, John B.; Baker, Joel A.; Hollis, Christopher J.; Morgans, Hugh E. G.; Smith, Euan G. C.

2010-11-01

We have used laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to measure elemental (Mg/Ca, Al/Ca, Mn/Ca, Zn/Ca, Sr/Ca, and Ba/Ca) ratios of 13 species of variably preserved early to middle Eocene planktonic and benthic foraminifera from New Zealand. The foraminifera were obtained from Ashley Mudstone, mid-Waipara River, South Island, which was deposited at bathyal depth ( ca. 1000 m) on the northern margin of the east-facing Canterbury Basin at a paleo-latitude of ca. 55°S. LA-ICP-MS data yield trace element depth profiles through foraminifera test walls that can be used to identify and exclude zones of surficial contamination and infilling material resulting from diagenetic coatings, mineralisation and detrital sediment. Screened Mg/Ca ratios from 5 species of foraminifera are used to calculate sea temperatures from late Early to early Middle Eocene ( ca. 51 to 46.5 Ma), a time interval that spans the termination of the Early Eocene Climatic Optimum (EECO). During this time, sea surface temperatures (SST) varied from 30 to 24 °C, and bottom water temperatures (BWT) from 21 to 14 °C. Comparison of Mg/Ca sea temperatures with published δ 18O and TEX 86 temperature data from the same samples (Hollis et al., 2009) shows close correspondence, indicating that LA-ICP-MS can provide reliable Mg/Ca sea temperatures even where foraminiferal test preservation is variable. Agreement between the three proxies also implies that Mg/Ca-temperature calibrations for modern planktonic and benthic foraminifera can generally be applied to Eocene species, although some species (e.g., V. marshalli) show significant calibration differences. The Mg/Ca ratio of the Eocene ocean is constrained by our data to be 35-50% lower than the modern ocean depending on which TEX 86 - temperature calibration (Kim et al., 2008; Liu et al., 2009) - is used to compare with the Mg/Ca sea temperatures. Sea temperatures derived from δ 18O analysis of foraminifera from Waipara show

Data Validation Package - June 2016 Groundwater and Surface Water Sampling at the Green River, Utah, Disposal Site

Energy Technology Data Exchange (ETDEWEB)

Linard, Joshua [USDOE Office of Legacy Management, Washington, DC (United States); Price, Jeffrey [Navarro Research and Engineering, Inc., Las Vegas, NV (United States)

2016-10-10

This event included annual sampling of groundwater and surface water locations at the Green River, Utah, Disposal Site. Sampling and analyses were conducted as specified in Sampling and Analysis Plan for US. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated, http://energy.gov/lrnldownloads/sampling-and- analysis-plan-us-department-energy-office-legacy-management-sites). Samples were collected from 15 monitoring wells and two surface locations at the disposal site as specified in the draft 2011 Ground Water Compliance Action Plan for the Green River, Utah, Disposal Site. Planned monitoring locations are shown in Attachment 1, Sampling and Analysis Work Order. A duplicate sample was collected from location 0179. One equipment blank was collected during this sampling event. Water levels were measured at all monitoring wells that were sampled. See Attachment 2, Trip Reports for additional details. The analytical data and associated qualifiers can be viewed in environmental database reports and are also available for viewing with dynamic mapping via the GEMS (Geospatial Environmental Mapping System) website at http://gems.lm.doe.gov/#. No issues were identified during the data validation process that requires additional action or follow-up.

The Assessment of Green Water Based on the SWAT Model: A Case Study in the Hai River Basin, China

Directory of Open Access Journals (Sweden)

Kui Zhu

2018-06-01

Full Text Available Green water accounts for two-thirds of precipitation, and the proportion could be even higher in dry years. Conflicts between water supply and demand have gradually become severe in the Hai River Basin (HRB due to the socio-economic development. Thus, the exploitation and the utilization of green water have attracted increasing attention. By gathering the related hydrological, meteorological, and geographic data, the spatiotemporal distribution of green water in HRB and the impacts of land use types on green water are analyzed based on the SWAT (Soil and Water Assessment Tool model in this study. Furthermore, three new indices are proposed for evaluation, including the maximum possible storage of green water (MSGW, the consumed green water (CGW, and the utilizable green water (UGW. The results show that (1 the MSGW is relatively low in plain areas and its spatial distribution is significantly associated with the soil type; (2 according to the evaluation results of CGW and UGW in HRB, a further improvement of utilization efficiency of green water could be achieved; (3 in general, the utilization efficiency of precipitation in farmlands is higher than other land use types, which means that the planting of appropriate plants could be helpful to enhance the utilization efficiency of green water. Our results summarize the spatiotemporal distribution of green water resource and provide a reference for water resources management in other water-short agricultural areas.

A small galliform bird from the Lower Eocene Fur Formation, northwestern Denmark

DEFF Research Database (Denmark)

Lindow, Bent Erik Kramer; Dyke, Gareth John

2007-01-01

A pair of fossilized imprints of feet represent the first published galliform (landfowl) specimen from the Lower Eocene Fur Formation of northwest Denmark. The specimen is referable to Galliformes due to the presence of a distinctly asymmetric trochlea metatarsi III. The specimen appears distinct...... from previously described Eocene Galliformes (e.g. Gallinuloididae, Quercymegapodiidae and Paraortygidae) and may represent a new taxon of Galliformes, increasing the diversity of this group in the Lower Eocene....

Hydrologic alteration affects aquatic plant assemblages in an arid-land river

Science.gov (United States)

Vinson, Mark; Hestmark, Bennett; Barkworth, Mary E.

2014-01-01

We evaluated the effects of long-term flow alteration on primary-producer assemblages. In 1962, Flaming Gorge Dam was constructed on the Green River. The Yampa River has remained an unregulated hydrologically variable river that joins the Green River 100 km downstream from Flaming Gorge Dam. In the 1960s before dam construction only sparse occurrences of two macroalgae, Cladophora and Chara, and no submerged vascular plants were recorded in the Green and Yampa rivers. In 2009–2010, aquatic plants were abundant and widespread in the Green River from the dam downstream to the confluence with the Yampa River. The assemblage consisted of six vascular species, Elodea canadensis, Myriophyllum sibiricum, Nasturtium officinale,Potamogeton crispus, Potamogeton pectinatus, and Ranunculus aquatilis, the macroalgae Chara and Cladophora, and the bryophyte, Amblystegium riparium. In the Green River downstream from the Yampa River, and in the Yampa River, only sparse patches of Chara and Cladophora growing in the splash zone on boulders were collected. We attribute the observed changes in the Green River to an increase in water transparency and a reduction in suspended and bed-load sediment and high flow disturbances. The lack of hydrophyte colonization downstream from the confluence with the Yampa River has implications for understanding tributary amelioration of dam effects and for designing more natural flow-regime schedules downstream from large dams.

Towards a robust and consistent middle Eocene astronomical timescale

Science.gov (United States)

Boulila, Slah; Vahlenkamp, Maximilian; De Vleeschouwer, David; Laskar, Jacques; Yamamoto, Yuhji; Pälike, Heiko; Kirtland Turner, Sandra; Sexton, Philip F.; Westerhold, Thomas; Röhl, Ursula

2018-03-01

Until now, the middle Eocene has remained a poorly constrained interval of efforts to produce an astrochronological timescale for the entire Cenozoic. This has given rise to a so-called "Eocene astronomical timescale gap" (Vandenberghe et al., 2012). A high-resolution astrochronological calibration for this interval has proven to be difficult to realize, mainly because carbonate-rich deep-marine sequences of this age are scarce. In this paper, we present records from middle Eocene carbonate-rich sequences from the North Atlantic Southeast Newfoundland Ridge (IODP Exp. 342, Sites U1408 and U1410), of which the cyclical sedimentary patterns allow for an orbital calibration of the geologic timescale between ∼38 and ∼48 Ma. These carbonate-rich cyclic sediments at Sites U1408 and U1410 were deposited as drift deposits and exhibit prominent lithological alternations (couplets) between greenish nannofossil-rich clay and white nannofossil ooze. The principal lithological couplet is driven by the obliquity of Earth's axial tilt, and the intensity of their expression is modulated by a cyclicity of about 173 kyr. This cyclicity corresponds to the interference of secular frequencies s3 and s6 (related to the precession of nodes of the Earth and Saturn, respectively). This 173-kyr obliquity amplitude modulation cycle is exceptionally well recorded in the XRF (X-ray fluorescence)-derived Ca/Fe ratio. In this work, we first demonstrate the stability of the (s3-s6) cycles using the latest astronomical solutions. Results show that this orbital component is stable back to at least 50 Ma, and can thus serve as a powerful geochronometer in the mid-Eocene portion of the Cenozoic timescale. We then exploit this potential by calibrating the geochronology of the recovered middle Eocene timescale between magnetic polarity Chrons C18n.1n and C21n. Comparison with previous timescales shows similarities, but also notable differences in durations of certain magnetic polarity chrons. We

Asian monsoons in a late Eocene greenhouse world.

Science.gov (United States)

Licht, A; van Cappelle, M; Abels, H A; Ladant, J-B; Trabucho-Alexandre, J; France-Lanord, C; Donnadieu, Y; Vandenberghe, J; Rigaudier, T; Lécuyer, C; Terry, D; Adriaens, R; Boura, A; Guo, Z; Soe, Aung Naing; Quade, J; Dupont-Nivet, G; Jaeger, J-J

2014-09-25

The strong present-day Asian monsoons are thought to have originated between 25 and 22 million years (Myr) ago, driven by Tibetan-Himalayan uplift. However, the existence of older Asian monsoons and their response to enhanced greenhouse conditions such as those in the Eocene period (55-34 Myr ago) are unknown because of the paucity of well-dated records. Here we show late Eocene climate records revealing marked monsoon-like patterns in rainfall and wind south and north of the Tibetan-Himalayan orogen. This is indicated by low oxygen isotope values with strong seasonality in gastropod shells and mammal teeth from Myanmar, and by aeolian dust deposition in northwest China. Our climate simulations support modern-like Eocene monsoonal rainfall and show that a reinforced hydrological cycle responding to enhanced greenhouse conditions counterbalanced the negative effect of lower Tibetan relief on precipitation. These strong monsoons later weakened with the global shift to icehouse conditions 34 Myr ago.

Electronic tagging of green sturgeon reveals population structure and movement among estuaries

Science.gov (United States)

Lindley, S.T.; Erickson, D.L.; Moser, M.L.; Williams, G.; Langness, O.P.; McCovey, B.W.; Belchik, M.; Vogel, D.; Pinnix, W.; Kelly, J.T.; Heublein, J.C.; Klimley, A.P.

2011-01-01

Green sturgeon Acipenser medirostris spend much of their lives outside of their natal rivers, but the details of their migrations and habitat use are poorly known, which limits our understanding of how this species might be affected by human activities and habitat degradation.We tagged 355 green sturgeon with acoustic transmitters on their spawning grounds and in known nonspawning aggregation sites and examined their movement among these sites and other potentially important locations using automated data-logging hydrophones. We found that green sturgeon inhabit a number of estuarine and coastal sites over the summer, including the Columbia River estuary, Willapa Bay, Grays Harbor, and the estuaries of certain smaller rivers in Oregon, especially the Umpqua River estuary. Green sturgeon from different natal rivers exhibited different patterns of habitat use; most notably, San Francisco Bay was used only by Sacramento River fish, while the Umpqua River estuary was used mostly by fish from the Klamath and Rogue rivers. Earlier work, based on analysis of microsatellite markers, suggested that the Columbia River mixed stock was mainly composed of fish from the Sacramento River, but our results indicate that fish from the Rogue and Klamath River populations frequently use the Columbia River as well. We also found evidence for the existence of migratory contingentswithin spawning populations.Our findings have significant implications for the management of the threatened Sacramento River population of green sturgeon, which migrates to inland waters outside of California where anthropogenic impacts, including fisheries bycatch and water pollution, may be a concern. Our results also illustrate the utility of acoustic tracking to elucidate the migratory behavior of animals that are otherwise difficult to observe. ?? American Fisheries Society 2011.

Pronounced zonal heterogeneity in Eocene southern high-latitude sea surface temperatures

NARCIS (Netherlands)

Douglas, P.M.J.; Affek, H.P.; Ivany, L.C.; Houben, A.J.P.; Sijp, W.P.; Sluijs, A.; Schouten, S.; Pagani, M.

2014-01-01

Paleoclimate studies suggest that increased global warmth during the Eocene epoch was greatly amplified at high latitudes, a state that climate models cannot fully reproduce. However, proxy estimates of Eocene near-Antarctic sea surface temperatures (SSTs) have produced widely divergent results at

Sea surface salinity of the Eocene Arctic Azolla event using innovative isotope modeling

Science.gov (United States)

Speelman, E. N.; Sewall, J. O.; Noone, D.; Huber, M.; Sinninghe Damste, J. S.; Reichart, G. J.

2009-04-01

With the realization that the Eocene Arctic Ocean was covered with enormous quantities of the free floating freshwater fern Azolla, new questions regarding Eocene conditions facilitating these blooms arose. Our present research focuses on constraining the actual salinity of, and water sources for, the Eocene Arctic basin through the application of stable water isotope tracers. Precipitation pathways potentially strongly affect the final isotopic composition of water entering the Arctic Basin. Therefore we use the Community Atmosphere Model (CAM3), developed by NCAR, combined with a recently developed integrated isotope tracer code to reconstruct the isotopic composition of global Eocene precipitation and run-off patterns. We further addressed the sensitivity of the modeled hydrological cycle to changes in boundary conditions, such as pCO2, sea surface temperatures (SSTs) and sea ice formation. In this way it is possible to assess the effect of uncertainties in proxy estimates of these parameters. Overall, results of all runs with Eocene boundary conditions, including Eocene topography, bathymetry, vegetation patterns, TEX86 derived SSTs and pCO2 estimates, show the presence of an intensified hydrological cycle with precipitation exceeding evaporation in the Arctic region. Enriched, precipitation weighted, isotopic values of around -120‰ are reported for the Arctic region. Combining new results obtained from compound specific isotope analyses (δD) on terrestrially derived n-alkanes extracted from Eocene sediments, and model outcomes make it possible to verify climate reconstructions for the middle Eocene Arctic. Furthermore, recently, characteristic long-chain mid-chain ω20 hydroxy wax constituents of Azolla were found in ACEX sediments. δD values of these C32 - C36 diols provide insight into the isotopic composition of the Eocene Arctic surface water. As the isotopic signature of the runoff entering the Arctic is modelled, and the final isotopic composition of

Pronounced zonal heterogeneity in Eocene southern high-latitude sea surface temperatures.

Science.gov (United States)

Douglas, Peter M J; Affek, Hagit P; Ivany, Linda C; Houben, Alexander J P; Sijp, Willem P; Sluijs, Appy; Schouten, Stefan; Pagani, Mark

2014-05-06

Paleoclimate studies suggest that increased global warmth during the Eocene epoch was greatly amplified at high latitudes, a state that climate models cannot fully reproduce. However, proxy estimates of Eocene near-Antarctic sea surface temperatures (SSTs) have produced widely divergent results at similar latitudes, with SSTs above 20 °C in the southwest Pacific contrasting with SSTs between 5 and 15 °C in the South Atlantic. Validation of this zonal temperature difference has been impeded by uncertainties inherent to the individual paleotemperature proxies applied at these sites. Here, we present multiproxy data from Seymour Island, near the Antarctic Peninsula, that provides well-constrained evidence for annual SSTs of 10-17 °C (1σ SD) during the middle and late Eocene. Comparison of the same paleotemperature proxy at Seymour Island and at the East Tasman Plateau indicate the presence of a large and consistent middle-to-late Eocene SST gradient of ∼7 °C between these two sites located at similar paleolatitudes. Intermediate-complexity climate model simulations suggest that enhanced oceanic heat transport in the South Pacific, driven by deep-water formation in the Ross Sea, was largely responsible for the observed SST gradient. These results indicate that very warm SSTs, in excess of 18 °C, did not extend uniformly across the Eocene southern high latitudes, and suggest that thermohaline circulation may partially control the distribution of high-latitude ocean temperatures in greenhouse climates. The pronounced zonal SST heterogeneity evident in the Eocene cautions against inferring past meridional temperature gradients using spatially limited data within given latitudinal bands.

First Record of Eocene Bony Fishes and Crocodyliforms from Canada’s Western Arctic

Science.gov (United States)

Eberle, Jaelyn J.; Gottfried, Michael D.; Hutchison, J. Howard; Brochu, Christopher A.

2014-01-01

Background Discovery of Eocene non-marine vertebrates, including crocodylians, turtles, bony fishes, and mammals in Canada’s High Arctic was a critical paleontological contribution of the last century because it indicated that this region of the Arctic had been mild, temperate, and ice-free during the early – middle Eocene (∼53–50 Ma), despite being well above the Arctic Circle. To date, these discoveries have been restricted to Canada’s easternmost Arctic – Ellesmere and Axel Heiberg Islands (Nunavut). Although temporally correlative strata crop out over 1,000 km west, on Canada’s westernmost Arctic Island – Banks Island, Northwest Territories – they have been interpreted as predominantly marine. We document the first Eocene bony fish and crocodyliform fossils from Banks Island. Principal Findings We describe fossils of bony fishes, including lepisosteid (Atractosteus), esocid (pike), and amiid, and a crocodyliform, from lower – middle Eocene strata of the Cyclic Member, Eureka Sound Formation within Aulavik National Park (∼76°N. paleolat.). Palynology suggests the sediments are late early to middle Eocene in age, and likely spanned the Early Eocene Climatic Optimum (EECO). Conclusions/Significance These fossils extend the geographic range of Eocene Arctic lepisosteids, esocids, amiids, and crocodyliforms west by approximately 40° of longitude or ∼1100 km. The low diversity bony fish fauna, at least at the family level, is essentially identical on Ellesmere and Banks Islands, suggesting a pan-High Arctic bony fish fauna of relatively basal groups around the margin of the Eocene Arctic Ocean. From a paleoclimatic perspective, presence of a crocodyliform, gar and amiid fishes on northern Banks provides further evidence that mild, year-round temperatures extended across the Canadian Arctic during early – middle Eocene time. Additionally, the Banks Island crocodyliform is consistent with the phylogenetic hypothesis of a Paleogene divergence

Seasonal variability in Arctic temperatures during the early Eocene

Science.gov (United States)

Eberle, J. J.; Fricke, H. C.; Humphrey, J.; Hackett, L.; Newbrey, M.; Hutchison, H.

2009-12-01

As a deep time analog for today’s rapidly warming Arctic region, early Eocene (~53 Ma) rocks on Ellesmere Island, Arctic Canada (~79° N.) preserve evidence of lush swamp forests inhabited by turtles, alligators, primates, tapirs, and hippo-like Coryphodon. Although the rich flora and fauna of the early Eocene Arctic imply warmer, wetter conditions that at present, quantitative estimates of Eocene Arctic climate are rare. By analyzing oxygen isotope ratios of biogenic phosphate from mammal, fish, and turtle fossils from a single locality on central Ellesmere Island, we provide estimates of early Eocene Arctic temperature, including mean annual temperature (MAT) of ~ 8° C, mean annual range in temperature (MART) of ~ 16.5° C, warm month mean temperature (WMMT) of 16 - 19° C, and cold month mean temperature (CMMT) of 0 - 1° C. Our seasonal range in temperature is similar to the range in estimated MAT obtained using different proxies. In particular, unusually high estimates of early Eocene Arctic MAT and sea surface temperature (SST) by others that are based upon the distribution of branched glycerol dialkyl glycerol tetraether (GDGT) membrane lipids in terrestrial soil bacteria and marine Crenarchaeota fall within our range of WMMT, suggesting a bias towards summer values. Consequently, caution should be taken when using these methods to infer MAT and SST that, in turn, are used to constrain climate models. From a paleontologic perspective, our temperature estimates verify that alligators and tortoises, by way of nearest living relative-based climatic inference, are viable paleoclimate proxies for mild, above-freezing year-round temperatures. Although in both of these reptiles, past temperature tolerances were greater than in their living descendants.

Agricultural implications of reduced water supplies in the Green and Upper Yellowstone River Basins

Energy Technology Data Exchange (ETDEWEB)

Lansford, R. R.; Roach, F.; Gollehon, N. R.; Creel, B. J.

1982-02-01

The growth of the energy sector in the energy-rich but water-restricted Western US has presented a potential conflict with the irrigated agricultural sector. This study measures the direct impacts on farm income and employment resulting from the transfer of water from agriculture to energy in two specific geographical areas - the Green and Upper Yellowstone River Basins. We used a linear programming model to evaluate the impacts of reduced water supplies. Through the use of regional multipliers, we expanded our analysis to include regional impacts. Volume I provides the major analysis of these impacts. Volume II provides further technical data.

Neutron moisture monitoring (NMM) and moisture contents in the Green River, Utah, UMTRA disposal cell

International Nuclear Information System (INIS)

1992-06-01

This report provides the basis for the US Department of Energy's (DOE) request to discontinue neutron moisture monitoring (NMM) at the Green River, Utah, Uranium Mill Tailings Remedial Action (UMTRA) disposal cell and decommission the neutron access holes. After 3 years of monitoring the disposal cell, the DOE has determined that the NMM method is not suitable for determining changes in moisture content in the disposal cell. Existing tailings moisture contents in the disposal cell result in a low seepage flux. The combination of a low seepage flux and geochemical retardation by foundation materials underneath the disposal cell ensures that the proposed US Environmental Protection Agency (EPA) groundwater protection standards will not be exceeded within the design life of the disposal cell. To assess the effectiveness of the NMM method for monitoring moisture contents In the disposal cell at Green River, the DOE subsequently conducted a field study and a review of historical and new literature. The literature review allowed the DOE to identify performance criteria for the NMM method. Findings of these studies suggest that: The NMM method is not sensitive to the low moisture contents found in the disposal cell.; there is an insufficient range of moisture contents in the disposal cell to develop a field calibration curve relating moisture content to neutron counts; it is not possible to collect NMM data from the disposal cell that meet data quality objectives for precision and accuracy developed from performance criteria described in the literature

Eocene Acritarchs of Taiwan

Directory of Open Access Journals (Sweden)

Cheng-Long Shaw

2001-03-01

Full Text Available Four new taxa (Multiplicisphaeridium taiwanianum C. L. Shaw sp. nov., Trichosphaeridium taiwanianum C. L. Shaw sp. nov., Tylosphaeridium taiwanianum C. L. Shaw sp. nov., and Cymatiosphaera taiwaniana C. L. Shaw sp. nov. of the fossil acritarchs obtained from Eocene sediments from offshore of the Keelung area in northern Taiwan are reported. They belong to two subgroups, four genera.

Lytostratigraphy of the eocene sediments in the Serbian-Macedonian Massif, Republic of Macedonia

OpenAIRE

Stojanova, Violeta; Petrov, Gose; Sijakova-Ivanova, Tena

2017-01-01

This paper presents the lithostratography of the eocene sedimentary series in the Serbian Macedonian massif on the territory of the Republic of Macedonia. Sediments of Eocene age in the Serbian Macedonian massif are represented in the Delchevo, Deve Bair and Strumi ca basin, with the orientation of NW-SE to S-J. With lithostratigraphic studies of eocene sediments in the basins in SMM, 3 superposition lithostratigraphic units (lithozones) were isolated:...

Detrital zircon U-Pb geochronological and sedimentological study of the Simao Basin, Yunnan: Implications for the Early Cenozoic evolution of the Red River

Science.gov (United States)

Chen, Yi; Yan, Maodu; Fang, Xiaomin; Song, Chunhui; Zhang, Weilin; Zan, Jinbo; Zhang, Zhiguo; Li, Bingshuai; Yang, Yongpeng; Zhang, Dawen

2017-10-01

The paleo-Red River is suggested to have been a continental-scale drainage system connecting the Tibetan Plateau to the South China Sea. However, the evolution of the paleo-Red River is still under debate. This study presents new results from sedimentological analyses and detrital zircon U-Pb geochronologic data from fluvial sedimentary rocks of Paleocene to Oligocene age of the Simao Basin to constrain the nature of the paleo-drainage system of the Red River. The detrital zircon U-Pb results reveal multiple age groups at 190-240 Ma, 260-280 Ma, 450-540 Ma, 1700-1900 Ma and 2400-2600 Ma for the Paleocene to late Eocene Denghei Formation (Fm.), but only one conspicuous peak at 220-240 Ma for the late Eocene-Oligocene Mengla Fm. Provenance analyses illustrate that the former likely had source areas that included the Hoh-Xil, Songpan-Ganzi, northern Qiangtang, Yidun and western Yangtze Terranes, which are consistent with the catchments of the Upper and Lower Jinshajiang Segments, whereas the latter mainly transported material from a limited number of sources, such as the Lincang granitic intrusions west of the Simao Basin. Integrated with available detrital zircon U-Pb geochronologic and paleogeographic data, our study suggests the existence of a paleo-Red River during the Paleocene to late Eocene that was truncated and lost its northern sources after approximately 35 Ma, due to left-lateral strike-slip faulting of the Ailao Shan-Red River and clockwise rotation of the Lanping-Simao Terrane.

Stratigraphic and climatic implications of clay mineral changes around the Paleocene/Eocene boundary of the northeastern US margin

Science.gov (United States)

Gibson, T.G.; Bybell, L.M.; Mason, D.B.

2000-01-01

Kaolinite usually is present in relatively small amounts in most upper Paleocene and lower Eocene neritic deposits of the northern US Atlantic Coastal Plain. However, there is a short period (less than 200,000 k.y.) in the latest Paleocene (upper part of calcareous nannoplankton Zone NP 9) when kaolinite-dominated clay mineral suites replaced the usual illite/smectite-dominated suites. During this time of global biotic and lithologic changes, kaolinite increased from less than 5% of the clay mineral suite to peak proportions of 50-60% of the suite and then returned to less than 5% in uppermost Paleocene/lowermost Eocene strata. This kaolinite pulse is present at numerous localities from southern Virginia to New Jersey. These sites represent both inner and middle neritic depositional environments and reflect input from several river drainage systems. Thus, it is inferred that kaolinite-rich source areas were widespread in the northeastern US during the latest Paleocene. Erosion of these source areas contributed the kaolinite that was transported and widely dispersed into shelf environments of the Salisbury embayment. The kaolinite increase, which occurred during a time of relatively high sea level, probably is the result of intensified weathering due to increased temperature and precipitation. The southern extent of the kaolinite pulse is uncertain in that uppermost Paleocene beds have not been identified in the southern Atlantic Coastal Plain. The late Paleocene kaolinite pulse that consists of an increase to peak kaolinite levels followed by a decrease can be used for detailed correlation between more upbasin and more downbasin sections in the Salisbury embayment. Correlations show that more upbasin Paleocene/Eocene boundary sections are erosionally truncated. They have varying portions of the kaolinite increase and, if present at all, discontinuous portions of the subsequent kaolinite decrease. As these truncated sections are disconformably overlain by lower

Eocene relatives of cod icefishes (Perciformes: Notothenioidei) from Seymour Island, Antarctica

DEFF Research Database (Denmark)

Bieńkowska-Wasiluk, Małgorzata; Bonde, Niels Christensøn; Møller, Peter Rask

2013-01-01

Fragmentary skull bones and vertebra from the Upper Eocene La Meseta Formation on Seymour (Marambio) Island, Antarctic Peninsula have been described as gadiform fishes, informally named “Mesetaichthys”. Here we describe jaws as Mesetaichthys jerzmanskae n. g. and n. sp., and refer this taxon...... to the perciform suborder Notothenioidei. This group is almost unknown as fossils. Similarities to the living, ‘primitive’ nototheniid Dissostichus eleginoides are indicated in the dentition. Gadiform evolution in the Paleocene-Eocene, and the possibility of a correlation between the origin and evolution...... of notothenioids in connection with the deterioration of the climate in Antarctica during the Late Eocene-Oligocene is discussed....

Multiple states in the late Eocene ocean circulation

Science.gov (United States)

Baatsen, M. L. J.; von der Heydt, A. S.; Kliphuis, M.; Viebahn, J.; Dijkstra, H. A.

2018-04-01

The Eocene-Oligocene Transition (EOT) marks a major step within the Cenozoic climate in going from a greenhouse into an icehouse state, with the formation of a continental-scale Antarctic ice sheet. The roles of steadily decreasing CO2 concentrations versus changes in ocean circulation at the EOT are still debated and the threshold for Antarctic glaciation is obscured by uncertainties in global geometry. Here, a detailed study of the late Eocene ocean circulation is carried out using an ocean general circulation model under two slightly different geography reconstructions of the middle-to-late Eocene (38 Ma). Using the same atmospheric forcing, both geographies give a profoundly different equilibrium ocean circulation state. The underlying reason for this sensitivity is the presence of multiple equilibria characterised by either North or South Pacific deep water formation. A possible shift from a southern towards a northern overturning circulation would result in significant changes in the global heat distribution and consequently make the Southern Hemisphere climate more susceptible for significant cooling and ice sheet formation on Antarctica.

High bat (Chiroptera) diversity in the Early Eocene of India

Science.gov (United States)

Smith, Thierry; Rana, Rajendra S.; Missiaen, Pieter; Rose, Kenneth D.; Sahni, Ashok; Singh, Hukam; Singh, Lachham

2007-12-01

The geographic origin of bats is still unknown, and fossils of earliest bats are rare and poorly diversified, with, maybe, the exception of Europe. The earliest bats are recorded from the Early Eocene of North America, Europe, North Africa and Australia where they seem to appear suddenly and simultaneously. Until now, the oldest record in Asia was from the Middle Eocene. In this paper, we report the discovery of the oldest bat fauna of Asia dating from the Early Eocene of the Cambay Formation at Vastan Lignite Mine in Western India. The fossil taxa are described on the basis of well-preserved fragments of dentaries and lower teeth. The fauna is highly diversified and is represented by seven species belonging to seven genera and at least four families. Two genera and five species are new. Three species exhibit very primitive dental characters, whereas four others indicate more advanced states. Unexpectedly, this fauna presents strong affinities with the European faunas from the French Paris Basin and the German Messel locality. This could result from the limited fossil record of bats in Asia, but could also suggest new palaeobiogeographic scenarios involving the relative position of India during the Early Eocene.

Impact ejecta at the Paleocene-Eocene boundary.

Science.gov (United States)

Schaller, Morgan F; Fung, Megan K; Wright, James D; Katz, Miriam E; Kent, Dennis V

2016-10-14

Extraterrestrial impacts have left a substantial imprint on the climate and evolutionary history of Earth. A rapid carbon cycle perturbation and global warming event about 56 million years ago at the Paleocene-Eocene (P-E) boundary (the Paleocene-Eocene Thermal Maximum) was accompanied by rapid expansions of mammals and terrestrial plants and extinctions of deep-sea benthic organisms. Here, we report the discovery of silicate glass spherules in a discrete stratigraphic layer from three marine P-E boundary sections on the Atlantic margin. Distinct characteristics identify the spherules as microtektites and microkrystites, indicating that an extraterrestrial impact occurred during the carbon isotope excursion at the P-E boundary. Copyright © 2016, American Association for the Advancement of Science.

Eocene cooling linked to early flow across the Tasmanian Gateway.

Science.gov (United States)

Bijl, Peter K; Bendle, James A P; Bohaty, Steven M; Pross, Jörg; Schouten, Stefan; Tauxe, Lisa; Stickley, Catherine E; McKay, Robert M; Röhl, Ursula; Olney, Matthew; Sluijs, Appy; Escutia, Carlota; Brinkhuis, Henk

2013-06-11

The warmest global temperatures of the past 85 million years occurred during a prolonged greenhouse episode known as the Early Eocene Climatic Optimum (52-50 Ma). The Early Eocene Climatic Optimum terminated with a long-term cooling trend that culminated in continental-scale glaciation of Antarctica from 34 Ma onward. Whereas early studies attributed the Eocene transition from greenhouse to icehouse climates to the tectonic opening of Southern Ocean gateways, more recent investigations invoked a dominant role of declining atmospheric greenhouse gas concentrations (e.g., CO2). However, the scarcity of field data has prevented empirical evaluation of these hypotheses. We present marine microfossil and organic geochemical records spanning the early-to-middle Eocene transition from the Wilkes Land Margin, East Antarctica. Dinoflagellate biogeography and sea surface temperature paleothermometry reveal that the earliest throughflow of a westbound Antarctic Counter Current began ~49-50 Ma through a southern opening of the Tasmanian Gateway. This early opening occurs in conjunction with the simultaneous onset of regional surface water and continental cooling (2-4 °C), evidenced by biomarker- and pollen-based paleothermometry. We interpret that the westbound flowing current flow across the Tasmanian Gateway resulted in cooling of Antarctic surface waters and coasts, which was conveyed to global intermediate waters through invigorated deep convection in southern high latitudes. Although atmospheric CO2 forcing alone would provide a more uniform middle Eocene cooling, the opening of the Tasmanian Gateway better explains Southern Ocean surface water and global deep ocean cooling in the apparent absence of (sub-) equatorial cooling.

Icacinaceae from the eocene of Western North America.

Science.gov (United States)

Allen, Sarah E; Stull, Gregory W; Manchester, Steven R

2015-05-01

The Icacinaceae are a pantropical family of trees, shrubs, and climbers with an extensive Paleogene fossil record. Our improved understanding of phylogenetic relationships within the family provides an excellent context for investigating new fossil fruit and leaf material from the Eocene of western North America. We examined fossils from early and middle Eocene sediments of western Wyoming, northeastern Utah, northwestern Colorado, and Oregon and compared them with extant species of Iodes and other icacinaceous genera as well as previously described fossils of the family. Three new fossil species are described, including two based on endocarps (Iodes occidentalis sp. nov. and Icacinicaryites lottii sp. nov.) and one based on leaves (Goweria bluerimensis sp. nov.). The co-occurrence of I. occidentalis and G. bluerimensis suggests these might represent detached organs of a single species. A new genus, Biceratocarpum, is also established for morphologically distinct fossil fruits of Icacinaceae previously placed in Carpolithus. Biceratocarpum brownii gen. et comb. nov. resembles the London Clay species "Iodes" corniculata in possessing a pair of subapical protrusions. These fossils increase our knowledge of Icacinaceae in the Paleogene of North America and highlight the importance of the Northern Hemisphere in the early diversification of the family. They also document interchange with the Eocene flora of Europe and biogeographic connections with modern floras of Africa and Asia, where Icacinaceae are diverse today. The present-day restriction of this family to tropical regions offers ecological implications for the Eocene floras in which they occur. © 2015 Botanical Society of America, Inc.

Warm ocean processes and carbon cycling in the Eocene.

Science.gov (United States)

John, Eleanor H; Pearson, Paul N; Coxall, Helen K; Birch, Heather; Wade, Bridget S; Foster, Gavin L

2013-10-28

Sea surface and subsurface temperatures over large parts of the ocean during the Eocene epoch (55.5-33.7 Ma) exceeded modern values by several degrees, which must have affected a number of oceanic processes. Here, we focus on the effect of elevated water column temperatures on the efficiency of the biological pump, particularly in relation to carbon and nutrient cycling. We use stable isotope values from exceptionally well-preserved planktonic foraminiferal calcite from Tanzania and Mexico to reconstruct vertical carbon isotope gradients in the upper water column, exploiting the fact that individual species lived and calcified at different depths. The oxygen isotope ratios of different species' tests are used to estimate the temperature of calcification, which we converted to absolute depths using Eocene temperature profiles generated by general circulation models. This approach, along with potential pitfalls, is illustrated using data from modern core-top assemblages from the same area. Our results indicate that, during the Early and Middle Eocene, carbon isotope gradients were steeper (and larger) through the upper thermocline than in the modern ocean. This is consistent with a shallower average depth of organic matter remineralization and supports previously proposed hypotheses that invoke high metabolic rates in a warm Eocene ocean, leading to more efficient recycling of organic matter and reduced burial rates of organic carbon.

Chemical concentrations in water and suspended sediment, Green River to Lower Duwamish Waterway near Seattle, Washington, 2016–17

Science.gov (United States)

Conn, Kathleen E.; Black, Robert W.; Peterson, Norman T.; Senter, Craig A.; Chapman, Elena A.

2018-01-05

From August 2016 to March 2017, the U.S. Geological Survey (USGS) collected representative samples of filtered and unfiltered water and suspended sediment (including the colloidal fraction) at USGS streamgage 12113390 (Duwamish River at Golf Course, at Tukwila, Washington) during 13 periods of differing flow conditions. Samples were analyzed by Washington-State-accredited laboratories for a large suite of compounds, including metals, dioxins/furans, semivolatile compounds including polycyclic aromatic hydrocarbons, butyltins, the 209 polychlorinated biphenyl (PCB) congeners, and total and dissolved organic carbon. Concurrent with the chemistry sampling, water-quality field parameters were measured, and representative water samples were collected and analyzed for river suspended-sediment concentration and particle-size distribution. The results provide new data that can be used to estimate sediment and chemical loads transported by the Green River to the Lower Duwamish Waterway.

Fossil palm beetles refine upland winter temperatures in the Early Eocene Climatic Optimum.

Science.gov (United States)

Archibald, S Bruce; Morse, Geoffrey E; Greenwood, David R; Mathewes, Rolf W

2014-06-03

Eocene climate and associated biotic patterns provide an analog system to understand their modern interactions. The relationship between mean annual temperatures and winter temperatures-temperature seasonality-may be an important factor in this dynamic. Fossils of frost-intolerant palms imply low Eocene temperature seasonality into high latitudes, constraining average winter temperatures there to >8 °C. However, their presence in a paleocommunity may be obscured by taphonomic and identification factors for macrofossils and pollen. We circumvented these problems by establishing the presence of obligate palm-feeding beetles (Chrysomelidae: Pachymerina) at three localities (a fourth, tentatively) in microthermal to lower mesothermal Early Eocene upland communities in Washington and British Columbia. This provides support for warmer winter Eocene climates extending northward into cooler Canadian uplands.

Early to Middle Eocene vegetation dynamics at the Wilkes Land Margin (Antarctica)

NARCIS (Netherlands)

Contreras, L.; Pross, J.; Bijl, P.K.; Koutsodendris, A.; Raine, J.I.; van de Schootbrugge, B.; Brinkhuis, H.

2013-01-01

The early Eocene epoch was characterized by extreme global warmth, which in terrestrial settings was characterized by an expansion of near-tropical vegetation belts into the high latitudes. During the middle to late Eocene, global cooling caused the retreat of tropical vegetation to lower latitudes.

The effect of maturation on the configuration of pristane in sediments and petroleum

Science.gov (United States)

Patience, R. L.; Rowland, S. J.; Maxwell, J. R.

1978-01-01

The absolute stereochemistry of pristane in a sample of contemporary marine zooplankton, Messel shale (Germany) and Djatibarang (Java) crude has been determined by gas chromatographic methods. The relative stereochemistry in Irati shale (Brazil), Green River (U.S.) crude, Halibut (Australia) crude has also been determined, and confirmed for a sample of the Green River shale. The stereoisomer distributions indicate a loss of stereospecificity of the phytol-derived 6(R), 10(S) pristane with increasing geological maturation. For example, the least mature geological sample, the Eocene Messel shale, contains solely the 6(R), 10(S) isomer, whereas a mature sample, Djatibarange crude, contains 50% of the 6(R), 10(S) isomer and 25% of each of the 6(R), 10(R) and 6(S), 10(S) isomers.

Nutrient Reduction in Agricultural Green Infrastructure: An Analysis of the Raccoon River Watershed

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James F. Canning

2018-06-01

Full Text Available Agricultural intensification has had the undesirable effect of degrading water quality throughout the United States. Nitrate pollution presents a difficult problem for rural and urban communities, and it contributes to the immense Gulf of Mexico Hypoxia Zone. Current U.S. policy prohibits regulation of agricultural runoff because it is a nonpoint source. The Raccoon River Watershed upstream of Des Moines, Iowa, USA has some of the highest nitrate levels in the nation, and the drinking water utility in Des Moines unsuccessfully pursued litigation against drainage districts in the watershed. We propose a cooperative solution between urban residents and upstream rural residents—namely, the installation of agricultural green infrastructure in the form of riparian buffers throughout the watershed enabled by the principles of water quality trading. We compare this distributed, green approach with a centralized, gray approach (i.e., building a new nitrate removal facility at the drinking water utility. Using terrain analysis, we determined that first-order streams are the most fitting location for riparian buffers. We estimate the buffer installation to cost between $155–$185 million; maintenance of the current nitrate removal facility will cost $72 million, while a new facility could cost up to $184 million. Riparian buffer installation offers more indirect, non-quantified benefits than maintaining or building new centralized, gray treatment (e.g., living-wage jobs and in-stream water quality improvement. Our analysis could act as a model for water quality trading and distributed agricultural green infrastructure in other communities facing similar water quality challenges.

Biostratigraphy of a Paleocene–Eocene Foreland Basin boundary in southern Tibet

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Xiaoqiao Wan

2010-10-01

Full Text Available This study of the Paleocene–Eocene boundary within a foreland basin of southern Tibet, which was dominated by a carbonate ramp depositional environment, documents more complex environmental conditions than can be derived from studies of the deep oceanic environment. Extinction rates for larger foraminiferal species in the Zongpu-1 Section apply to up to 46% of the larger foraminiferal taxa. The extinction rate in southern Tibet is similar to rates elsewhere in the world, but it shows that the Paleocene fauna disappeared stepwise through the Late Paleocene, with Eocene taxa appearing abruptly above the boundary. A foraminifera turnover was identified between Members 3 and 4 of the Zongpu Formation—from the Miscellanea–Daviesina assemblage to an Orbitolites–Alveolina assemblage. The Paleocene and Eocene boundary is between the SBZ 4 and SBZ 5, where it is marked by the extinction of Miscellanea miscella and the first appearance of Alveolina ellipsodalis and a large number of Orbitolites. Chemostratigraphically, the δ13C values from both the Zongpu-1 and Zongpu-2 Sections show three negative excursions in the transitional strata, one in Late Paleocene, one at the boundary, and one in the early Eocene. The second negative excursion of δ13C, which is located at the P–E boundary, coincides with larger foraminifera overturn. These faunal changes and the observed δ13C negative excursions provide new evidence on environmental changes across the Paleocene–Eocene boundary in Tibet.

Development of the Philippine Mobile Belt in northern Luzon from Eocene to Pliocene

Science.gov (United States)

Suzuki, Shigeyuki; Peña, Rolando E.; Tam, Tomas A.; Yumul, Graciano P.; Dimalanta, Carla B.; Usui, Mayumi; Ishida, Keisuke

2017-07-01

The origin of the Philippine Archipelago is characterized by the combination of the oceanic Philippine Mobile Belt (PMB) and the Palawan Continental Block (PCB). This paper is focused on the geologic evolution of the PMB in northern Luzon from Eocene to Pliocene. The study areas (northern Luzon) are situated in the central part of the PMB which is occupied by its typical components made up of a pre-Paleocene ophiolitic complex, Eocene successions, Eocene to Oligocene igneous complex and late Oligocene to Pliocene successions. Facies analysis of the middle Eocene and late Oligocene to early Pliocene successions was carried out to understand the depositional environment of their basins. Modal sandstone compositions, which reflect the basement geology of the source area, were analyzed. Major element geochemistry of sediments was considered to reconstruct the tectonic settings. The following brief history of the PMB is deduced. During the middle Eocene, the PMB was covered by mafic volcanic rocks and was a primitive island arc. In late Eocene to late Oligocene time, the intermediate igneous complex was added to the mafic PMB crust. By late Oligocene to early Miocene time, the PMB had evolved into a volcanic island arc setting. Contributions from alkalic rocks are detected from the rock fragments in the sandstones and chemical composition of the Zigzag Formation. During the middle Miocene to Pliocene, the tectonic setting of the PMB remained as a mafic volcanic island arc.

Paleocene-Eocene warming and biotic response in the epicontinental West Siberian Sea

NARCIS (Netherlands)

Frieling, Joost|info:eu-repo/dai/nl/338017909; Iakovleva, Alina I.; Reichart, Gert Jan|info:eu-repo/dai/nl/165599081; Aleksandrova, Galina N.; Gnibidenko, Zinaida N.; Schouten, Stefan|info:eu-repo/dai/nl/137124929; Sluijs, Appy|info:eu-repo/dai/nl/311474748

2014-01-01

We present a Paleocene-Eocene (ca. 60-52 Ma) sea-surface temperature record from sediments deposited in the epicontinental West Siberian Sea. TEX86 paleothermometry indicates long-term late Paleocene (~17 °C ca. 59 Ma) to early Eocene (26 °C at 52 Ma) sea-surface warming, consistent with trends

Chemistry which created Green River Formation oil shale

Energy Technology Data Exchange (ETDEWEB)

Smith, J.W.

1983-01-01

The genesis pattern presented for Green River Formation oil shale explains the major observation. Deposition of relatively large quantities of hydrogen-rich organic matter in the oil shales is a natural consequence of the chemical conditions (basic water and reducing atmosphere) and the physical limitation of clastic materials developed in the stratified ancient Lake Uinta. Stability of the stratification produced the continuous deposition of the organic matter and its uniformity over the deposit. Authigenic formation of the oil-shale minerals proceeds naturally from the lake stratification, and the varve production stems from the seasonable development of organic matter. The lake's stratification produced uniform deposition over the entire area it covered, making the correlatable lateral persistence of the thin laminations a natural consequence. As the lake developed, the attack on aluminosilicates by sodium carbonate in the lower layer produced a silicate skeleton protected by aluminum trihydroxide. On deposition, this aluminum-rich skeleton formed illite in quantity. As the lake became more basic, the protecting aluminum hydroxide coating dissolved amphoterically and illite production dropped at a specific point. Continual build-up of sodium carbonate and aluminate ion in the water of the lake's lower layer reached conditions which precipitated dawsonite and crystallized nahcolite in the sediment as a result of CO/sub 2/ production from organic matter. (JMT)

Paleocene–Eocene warming and biotic response in the epicontinental West Siberian Sea

NARCIS (Netherlands)

Frieling, J.; Iakovleva, A.I.; Reichart, G.-J.; Aleksandrova, G.N.; Gnibidenko, Z.N.; Schouten, S.; Sluijs, A.

2014-01-01

We present a Paleocene–Eocene (ca. 60–52 Ma) sea-surface temperature record from sediments deposited in the epicontinental West Siberian Sea. TEX86 paleothermometry indicates long-term late Paleocene (~17 °C ca. 59 Ma) to early Eocene (26 °C at 52 Ma) sea-surface warming, consistent with trends

Paleoceanographic, and paleoclimatic constraints on the global Eocene diatom and silicoflagellate record

Science.gov (United States)

Barron, John A.; Stickley, Catherine E.; Bukry, David

2015-01-01

Eocene diatom and silicoflagellate biostratigraphy are summarized and correlated with the most recent geologic time scale as well as with the global oxygen isotope and eustatic sea level curves. The global distribution of Eocene diatom/silicoflagellate-bearing sediments varies considerably, reflecting changing oceanic gateways and paleoceanography with changing patterns that are punctuated by four major depositional events.

A structural intermediate between triisodontids and mesonychians (Mammalia, Acreodi) from the earliest Eocene of Portugal.

Science.gov (United States)

Tabuce, Rodolphe; Clavel, Julien; Antunes, Miguel Telles

2011-02-01

A new mammal, Mondegodon eutrigonus gen. et sp. nov., is described from the earliest Eocene locality of Silveirinha, Portugal. This species shows dental adaptations indicative of a carnivorous diet. M. eutrigonus is referred to the order Acreodi and considered, along with the early Paleocene North American species Oxyclaenus cuspidatus, as a morphological intermediate between two groups of ungulate-like mammals, namely, the triisodontids and mesonychians. Considering that triisodontids are early to early-late Paleocene North American taxa, Mondegodon probably belongs to a group that migrated from North America towards Europe during the first part of the Paleocene. Mondegodon could represent thus a relict genus, belonging to the ante-Eocene European mammalian fauna. The occurrence of such a taxon in Southern Europe may reflect a period of isolation of this continental area during the Paleocene/Eocene transition. In this context, the non-occurrence of closely allied forms of Mondegodon in the Eocene North European mammalian faunas is significant. This strengthens the hypothesis that the mammalian fauna from Southern Europe is characterized by a certain degree of endemism during the earliest Eocene. Mondegodon also presents some striking similarities with an unnamed genus from the early Eocene of India which could represent the first Asian known transitional form between the triisodontids and mesonychians.

The chemistry which created Green River Formation oil shale

Energy Technology Data Exchange (ETDEWEB)

Smith, J.W.

1983-02-01

The genesis pattern presented for Green River Formation oil shale explains the major observation. Deposition of relatively large quantities of hydrogen-rich organic matter in the oil shales is a natural consequence of the chemical conditions (basic water and reducing atmosphere) and the physical limitation of clastic materials developed in the stratified ancient Lake Uinta. Stability of the stratification produced the continuous deposition of the organic matter and its uniformity over the deposit. Authigenic formation of the oil-shale minerals proceeds naturally from the lake stratification, and the varve production stems from the seasonable development of organic matter. The lake's stratification produced uniform deposition over the entire area it covered, making the correlatable lateral persistence of the thin laminations a natural consequence. As the lake developed, the attack on aluminosilicates by sodium carbonate in the lake's lower layer produced a silicate skeleton protected by aluminum trihydroxide. On deposition, this aluminum-rich skeleton formed illite in quantity. As the lake became more basic, the protecting aluminum hydroxide coating dissolved amphoterically and illite production dropped at a specific point. Continual build-up of sodium carbonate and aluminate ion in the water of the lake's lower layer reached conditions which

The oldest African bat from the early Eocene of El Kohol (Algeria).

Science.gov (United States)

Ravel, Anthony; Marivaux, Laurent; Tabuce, Rodolphe; Adaci, Mohammed; Mahboubi, Mohammed; Mebrouk, Fateh; Bensalah, Mustapha

2011-05-01

The Afro-Arabian Paleogene fossil record of Chiroptera is very poor. In North Africa and Arabia, this record is limited, thus far, to a few localities mainly in Tunisia (Chambi, late early Eocene), Egypt (Fayum, late Eocene to early Oligocene), and Sultanate of Oman (Taqah, early Oligocene). It consists primarily of isolated teeth or mandible fragments. Interestingly, these African fossil bats document two modern groups (Vespertilionoidea and Rhinolophoidea) from the early Eocene, while the bat fossil record of the same epoch of North America, Eurasia, and Australia principally includes members of the "Eochiroptera." This paraphyletic group contains all primitive microbats excluding modern families. In Algeria, the region of Brezina, southeast of the Atlas Mountains, is famous for the early Eocene El Kohol Formation, which has yielded one of the earliest mammalian faunas of the African landmass. Recent fieldwork in the same area has led to the discovery of a new vertebrate locality, including isolated teeth of Chiroptera. These fossils represent the oldest occurrence of Chiroptera in Africa, thus extending back the record of the group to the middle early Eocene (Ypresian) on that continent. The material consists of an upper molar and two fragments of lower molars. The dental character association matches that of "Eochiroptera." As such, although very fragmentary, the material testifies to the first occurrence of "Eochiroptera" in Algeria, and by extension in Africa. This discovery demonstrates that this basal group of Chiroptera had a worldwide distribution during the early Paleogene.

Suspended-sediment transport from the Green-Duwamish River to the Lower Duwamish Waterway, Seattle, Washington, 2013–17

Science.gov (United States)

Senter, Craig A.; Conn, Kathleen E.; Black, Robert W.; Peterson, Norman; Vanderpool-Kimura, Ann M.; Foreman, James R.

2018-02-28

The Green-Duwamish River transports watershed-derived sediment to the Lower Duwamish Waterway Superfund site near Seattle, Washington. Understanding the amount of sediment transported by the river is essential to the bed sediment cleanup process. Turbidity, discharge, suspended-sediment concentration (SSC), and particle-size data were collected by the U.S. Geological Survey (USGS) from February 2013 to January 2017 at the Duwamish River, Washington, within the tidal influence at river kilometer 16.7 (USGS streamgage 12113390; Duwamish River at Golf Course at Tukwila, WA). This report quantifies the timing and magnitude of suspended-sediment transported in the Duwamish River. Regression models were developed between SSC and turbidity and SSC and discharge to estimate 15- minute SSC. Suspended-sediment loads were calculated from the computed SSC and time-series discharge data for every 15-minute interval during the study period. The 2014–16 average annual suspended-sediment load computed was 117,246 tons (106,364 metric tons), of which 73.5 percent or (86,191 tons; 78,191 metric tons) was fine particle (less than 0.0625 millimeter in diameter) suspended sediment. The seasonality of this site is apparent when you divide the year into "wet" (October 16– April 15) and "dry" (April 16–October 15) seasons. Most (97 percent) of the annual suspended sediment was transported during the wet season, when brief periods of intense precipitation from storms, large releases from the Howard Hanson Dam, or a combination of both were much more frequent.

Effects of Flaming Gorge Dam hydropower operations on sediment transport in the Browns Park reach of the Green River, Utah and Colorado

International Nuclear Information System (INIS)

Williams, G.P.; Tomasko, D.; Cho, H.E.; Yin, S.C.L.

1995-05-01

Three methods for comparing sediment transport were applied to four proposed hydropower operational scenarios under study for Flaming Gorge Dam on the Green River in Utah. These methods were effective discharge, equilibrium potential, and cumulative sediment load with flow exceedance plots. Sediment loads transported by the Green River in the Browns Park reach were calculated with the Engelund-Hansen equation for three historical water years and four hydropower operational scenarios. A model based on the Engelund-Hansen equation was developed using site-specific information and validated by comparing predictions for a moderate water year with measured historical values. The three methods were used to assess the impacts of hydropower operational scenarios on sediment resources. The cumulative sediment load method provided the most useful information for impact evaluation. Effective discharge was not a useful tool because of the limited number of discrete flows associated with synthetic hydrographs for the hydropower operational scenarios. The equilibrium potential method was relatively insensitive to the variations in operating conditions, rendering it comparatively ineffective for impact evaluation

Terrestrial cooling in Northern Europe during the eocene-oligocene transition.

Science.gov (United States)

Hren, Michael T; Sheldon, Nathan D; Grimes, Stephen T; Collinson, Margaret E; Hooker, Jerry J; Bugler, Melanie; Lohmann, Kyger C

2013-05-07

Geochemical and modeling studies suggest that the transition from the "greenhouse" state of the Late Eocene to the "icehouse" conditions of the Oligocene 34-33.5 Ma was triggered by a reduction of atmospheric pCO2 that enabled the rapid buildup of a permanent ice sheet on the Antarctic continent. Marine records show that the drop in pCO2 during this interval was accompanied by a significant decline in high-latitude sea surface and deep ocean temperature and enhanced seasonality in middle and high latitudes. However, terrestrial records of this climate transition show heterogeneous responses to changing pCO2 and ocean temperatures, with some records showing a significant time lag in the temperature response to declining pCO2. We measured the Δ47 of aragonite shells of the freshwater gastropod Viviparus lentus from the Solent Group, Hampshire Basin, United Kingdom, to reconstruct terrestrial temperature and hydrologic change in the North Atlantic region during the Eocene-Oligocene transition. Our data show a decrease in growing-season surface water temperatures (~10 °C) during the Eocene-Oligocene transition, corresponding to an average decrease in mean annual air temperature of ~4-6 °C from the Late Eocene to Early Oligocene. The magnitude of cooling is similar to observed decreases in North Atlantic sea surface temperature over this interval and occurs during major glacial expansion. This suggests a close linkage between atmospheric carbon dioxide concentrations, Northern Hemisphere temperature, and expansion of the Antarctic ice sheets.

To Green or Not to Green? Evaluation of Green Stormwater Infrastructure in Kansas City Middle Blue River Project

Science.gov (United States)

The City of Kansas City, Mo., Water Services Department is implementing a pilot project to measure and evaluate the performance of green infrastructure. Information obtained through this pilot project will be used to guide the design of green solutions throughout Kansas City und...

Eocene diversification of crown group rails (Aves: Gruiformes: Rallidae).

Science.gov (United States)

García-R, Juan C; Gibb, Gillian C; Trewick, Steve A

2014-01-01

Central to our understanding of the timing of bird evolution is debate about an apparent conflict between fossil and molecular data. A deep age for higher level taxa within Neoaves is evident from molecular analyses but much remains to be learned about the age of diversification in modern bird families and their evolutionary ecology. In order to better understand the timing and pattern of diversification within the family Rallidae we used a relaxed molecular clock, fossil calibrations, and complete mitochondrial genomes from a range of rallid species analysed in a Bayesian framework. The estimated time of origin of Rallidae is Eocene, about 40.5 Mya, with evidence of intrafamiliar diversification from the Late Eocene to the Miocene. This timing is older than previously suggested for crown group Rallidae, but fossil calibrations, extent of taxon sampling and substantial sequence data give it credence. We note that fossils of Eocene age tentatively assigned to Rallidae are consistent with our findings. Compared to available studies of other bird lineages, the rail clade is old and supports an inference of deep ancestry of ground-dwelling habits among Neoaves.

Paleocene-Eocene Sediments Interbedded With Volcanics Within the Lycian Nappes: Faralya Formation

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Mustafa Şenel

1991-06-01

Full Text Available The presumably allochthonous structural units in the Southwestern Turkey between the Menderes massif and Beydağları autochthon are known as the Lycian nappes. Some of these units particularly beneath the ophiolite nappe end up with the Faralya formation of Paleocene-Lutetian age. The striking feature of this formation which includes micrite, clayey micrite, claystone, sandstone and conglomerate, is the presence of basic volcanite interbeds of Eocene age, This volcanite bearing formation exhibits a strong similarity to those of the other formations in Southwestern Turkey most of which include similar basic volcanites. Eocene basic volcanites are also known in the Akseki autochthon to the south of Seydişehir (Geyikdağ unit in broad sense. Similar extensive lateral movements (Eocene mountain building processes developed over the Faralya formation are seen over the volcanite bearing formations to the south of Menderes massif as well as to the north of Isparta angle and the Akseki autochthon. These features indicate that the area between the Menderes massif and Akseki autochthon (Geyikdağ unit reflects common basinal characters in terms of depositional conditions, volcanism and the traces of Eocene mountain building process.

Nonexplosive and explosive magma/wet-sediment interaction during emplacement of Eocene intrusions into Cretaceous to Eocene strata, Trans-Pecos igneous province, West Texas

Science.gov (United States)

Befus, K.S.; Hanson, R.E.; Miggins, D.P.; Breyer, J.A.; Busbey, A.B.

2009-01-01

Eocene intrusion of alkaline basaltic to trachyandesitic magmas into unlithified, Upper Cretaceous (Maastrichtian) to Eocene fluvial strata in part of the Trans-Pecos igneous province in West Texas produced an array of features recording both nonexplosive and explosive magma/wet-sediment interaction. Intrusive complexes with 40Ar/39Ar dates of ~ 47-46??Ma consist of coherent basalt, peperite, and disrupted sediment. Two of the complexes cutting Cretaceous strata contain masses of conglomerate derived from Eocene fluvial deposits that, at the onset of intrusive activity, would have been > 400-500??m above the present level of exposure. These intrusive complexes are inferred to be remnants of diatremes that fed maar volcanoes during an early stage of magmatism in this part of the Trans-Pecos province. Disrupted Cretaceous strata along diatreme margins record collapse of conduit walls during and after subsurface phreatomagmatic explosions. Eocene conglomerate slumped downward from higher levels during vent excavation. Coherent to pillowed basaltic intrusions emplaced at the close of explosive activity formed peperite within the conglomerate, within disrupted Cretaceous strata in the conduit walls, and within inferred remnants of the phreatomagmatic slurry that filled the vents during explosive volcanism. A younger series of intrusions with 40Ar/39Ar dates of ~ 42??Ma underwent nonexplosive interaction with Upper Cretaceous to Paleocene mud and sand. Dikes and sills show fluidal, billowed, quenched margins against the host strata, recording development of surface instabilities between magma and groundwater-rich sediment. Accentuation of billowed margins resulted in propagation of intrusive pillows into the adjacent sediment. More intense disruption and mingling of quenched magma with sediment locally produced fluidal and blocky peperite, but sufficient volumes of pore fluid were not heated rapidly enough to generate phreatomagmatic explosions. This work suggests that

Warm and wet conditions in the Arctic region during Eocene Thermal Maximum 2

NARCIS (Netherlands)

Sluijs, A.; Schouten, S.; Donders, T.H.; Schoon, P.L.; Röhl, U.; Reichart, G.-J.; Sangiorgi, F.; Kim, J.-H.; Sinninghe Damsté, J.S.; Brinkhuis, H.

2009-01-01

Several episodes of abrupt and transient warming, each lasting between 50,000 and 200,000 years, punctuated the long-term warming during the Late Palaeocene and Early Eocene (58 to 51 Myr ago) epochs1,2. These hyperthermal events, such as the Eocene Thermal Maximum 2 (EMT2) that took place about

Eocene Antarctic seasonality inferred from high-resolution stable isotope profiles of fossil bivalves and driftwood

Science.gov (United States)

Judd, E. J.; Ivany, L. C.; Miklus, N. M.; Uveges, B. T.; Junium, C. K.

2017-12-01

The Eocene Epoch was a time of large-scale global climate change, experiencing both the warmest temperatures of the Cenozoic and the onset of southern hemisphere glaciation. The record of average global temperatures throughout this transition is reasonably well constrained, however considerably less is known about the accompanying changes in seasonality. Seasonally resolved temperature data provide a wealth of information not readily available from mean annual temperature data alone. These data are particularly important in the climatically sensitive high latitudes, as they can elucidate the means by which climate changes and the conditions necessary for the growth of ice sheets. Several recent studies, however, have suggested the potential for monsoonal precipitation regimes in the early-middle Eocene high latitudes, which complicates interpretation of seasonally resolved oxygen isotope records in shallow nearshore marine settings. Seasonal precipitation and runoff could create a brackish, isotopically depleted lens in these environments, depleting summertime δ18Ocarb and thereby inflating the inferred mean and range of isotope-derived temperatures. Here, we assess intra-annual variations in temperature in shallow nearshore Antarctic waters during the middle and late Eocene, inferred from high-resolution oxygen isotope profiles from accretionary bivalves of the La Meseta Formation, Seymour Island, Antarctica. To address concerns related to precipitation and runoff, we also subsample exceptionally preserved fossil driftwood from within the formation and use seasonal differences in δ13Corg values to estimate the ratio of summertime to wintertime precipitation. Late Eocene oxygen isotope profiles exhibit strongly attenuated seasonal amplitudes and more enriched mean annual values in comparison with data from the middle Eocene. Preliminary fossil wood data are not indicative of a strongly seasonal precipitation regime, implying that intra-annual variation in oxygen

Mid-latitude continental temperatures through the early Eocene in western Europe

Science.gov (United States)

Inglis, Gordon N.; Collinson, Margaret E.; Riegel, Walter; Wilde, Volker; Farnsworth, Alexander; Lunt, Daniel J.; Valdes, Paul; Robson, Brittany E.; Scott, Andrew C.; Lenz, Olaf K.; Naafs, B. David A.; Pancost, Richard D.

2017-02-01

Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are increasingly used to reconstruct mean annual air temperature (MAAT) during the early Paleogene. However, the application of this proxy in coal deposits is limited and brGDGTs have only been detected in immature coals (i.e. lignites). Using samples recovered from Schöningen, Germany (∼48°N palaeolatitude), we provide the first detailed study into the occurrence and distribution of brGDGTs through a sequence of early Eocene lignites and associated interbeds. BrGDGTs are abundant and present in every sample. In comparison to modern studies, changes in vegetation type do not appear to significantly impact brGDGT distributions; however, there are subtle differences between lignites - representing peat-forming environments - and siliciclastic nearshore marine interbed depositional environments. Using the most recent brGDGT temperature calibration (MATmr) developed for soils, we generate the first continental temperature record from central-western continental Europe through the early Eocene. Lignite-derived MAAT estimates range from 23 to 26 °C while those derived from the nearshore marine interbeds exceed 20 °C. These estimates are consistent with other mid-latitude environments and model simulations, indicating enhanced mid-latitude, early Eocene warmth. In the basal part of the section studied, warming is recorded in both the lignites (∼2 °C) and nearshore marine interbeds (∼2-3 °C). This culminates in a long-term temperature maximum, likely including the Early Eocene Climatic Optimum (EECO). Although this long-term warming trend is relatively well established in the marine realm, it has rarely been shown in terrestrial settings. Using a suite of model simulations we show that the magnitude of warming at Schöningen is broadly consistent with a doubling of CO2, in agreement with late Paleocene and early Eocene pCO2 estimates.

Analysis of Benthic Foraminiferal Size Change During the Eocene-Oligocene Transition

Science.gov (United States)

Zachary, W.; Keating-Bitonti, C.

2017-12-01

The Eocene-Oligocene transition is a significant global cooling event with the first growth of continental ice on Antarctica. In the geologic record, the size of fossils can be used to indirectly observe how organisms respond to climate change. For example, organisms tend to be larger in cooler environments as a physiological response to temperature. This major global cooling event should influence organism physiology, resulting in significant size trends observed in the fossil record. Benthic foraminifera are protists and those that grow a carbonate shell are both well-preserved and abundant in marine sediments. Here, we used the foraminiferal fossil record to study the relationship between their size and global cooling. We hypothesize that cooler temperatures across the Eocene-Oligocene boundary promoted shell size increase. To test this hypothesis, we studied benthic foraminifera from 10 deep-sea cores drilled at Ocean Drilling Program Site 744, located in the southern Indian Ocean. We washed sediment samples over a 63-micron sieve and picked foraminifera from a 125-micron sieve. We studied the benthic foraminiferal genus Cibicidoides and its size change across this cooling event. Picked specimens were imaged and we measured the diameter of their shells using "imageJ". Overall, we find that Cibicidoides shows a general trend of increasing size during this transition. In particular, both the median and maximum sizes of Cibicidoides increase from the Eocene into the Oligocene. We also analyzed C. pachyderma and C. mundulus for size trends. Although both species increase in median size across the boundary, only C. pachyderma shows a consistent trend of increasing maximum, median, and minimum shell diameter. After the Eocene-Oligocene boundary, we observe that shell diameter decreases following peak cooling and that foraminiferal sizes remain stable into the early Oligocene. Therefore, the Eocene-Oligocene cooling event appears to have strong influence on shell size.

Urban green areas as the starting point for planning hydroelectric and urban developments: The case of the Sava River in the City of Ljubljana

Directory of Open Access Journals (Sweden)

Aleš Mlakar

2008-01-01

Full Text Available The article deals with the landscape and urbanistic layout of the Sava River space and North part of the Bežigrad stretch of Ljubljana. Focus is on methodological and content starting points for the layout preparation and development of urban green areas of the wider Sava River space, which as a connecting link and simultaneously independent spatial and functional entity represents the starting point for planning hydro-energetic and urban arrangements. The necessity of recognising and resolving real spatial planning issues, formulation of clear goals and concepts, confrontation of different spatial systems and interests, as well as the sensibility of devising alternative development scenarios are emphasised. One of the most important starting points of the proposed layout is comprehensive design of public open spaces and green areas. The urbanistic solution relies on a programmatically strong, distinct and structured Dunajska Street, which should transform into the public space of a modern urban artery, with a clear ending that simultaneously gradually adapts to the morphology akin to the surroundings and Sava River space. Because of its natural characteristics, preserved cultural landscape and good accessibility, this area has great potential for development of leisure activities. The proposed solution stems from the fact that the chain of hydro-electric plants shouldn't be seen as buildings with negative environmental effects, but also as development opportunities – the actual execution of a recreation area along the Sava River and a method for rehabilitating the degraded spaces. Comprehensive solutions along the river have been proposed as parts of the hydro-electric developments, with special attention focusing on active design of various riverbank types.

The palaeobiology of high latitude birds from the early Eocene greenhouse of Ellesmere Island, Arctic Canada.

Science.gov (United States)

Stidham, Thomas A; Eberle, Jaelyn J

2016-02-12

Fossils attributable to the extinct waterfowl clade Presbyornithidae and the large flightless Gastornithidae from the early Eocene (~52-53 Ma) of Ellesmere Island, in northernmost Canada are the oldest Cenozoic avian fossils from the Arctic. Except for its slightly larger size, the Arctic presbyornithid humerus is not distinguishable from fossils of Presbyornis pervetus from the western United States, and the Gastornis phalanx is within the known size range of mid-latitude individuals. The occurrence of Presbyornis above the Arctic Circle in the Eocene could be the result of annual migration like that of its living duck and geese relatives, or it may have been a year-round resident similar to some Eocene mammals on Ellesmere and some extant species of sea ducks. Gastornis, along with some of the mammalian and reptilian members of the Eocene Arctic fauna, likely over-wintered in the Arctic. Despite the milder (above freezing) Eocene climate on Ellesmere Island, prolonged periods of darkness occurred during the winter. Presence of these extinct birds at both mid and high latitudes on the northern continents provides evidence that future increases in climatic warming (closer to Eocene levels) could lead to the establishment of new migratory or resident populations within the Arctic Circle.

Radiological survey of the inactive uranium-mill tailings at Green River, Utah

International Nuclear Information System (INIS)

Haywood, F.F.; Christian, D.J.; Ellis, B.S.; Hubbard, H.M. Jr.; Lorenzo, D.; Shinpaugh, W.H.

1980-03-01

The uranium-mill tailings at Green River, Utah, are relatively low in 226 Ra content and concentration (20 Ci and 140 pCi/g, respectively) because the mill was used to upgrade the uranium ore by separating the sand and slime fractions; most of the radium was transported along with the slimes to another mill site. Spread of tailings was observed in all directions, but near-background gamma exposure rates were reached at distances of 40 to 90 m from the edge of the pile. Water erosion of the tailings is evident and, since a significant fraction of the tailings pile lies in Brown's Wash, the potential exists for repetition of the loss of a large quantity of tailings such as occurred during a flood in 1959. In general, the level of surface contamination was low at this site, but some areas in the mill site, which were being used for nonuranium work, have gamma-ray exposure rates up to 143 μR/hr

Tectonic Reorganization and the Cause of Paleocene and Eocene pCO2 Anomalies

Science.gov (United States)

Austermann, Jacqueline; Carter, Laura B.; Middleton, Jennifer; Stellmann, Jessica; Pyle, Lacey

2017-04-01

Oxygen isotope records reveal that deep-sea temperatures were relatively stable in the early and mid Paleocene before they rose by approx. 4°C to peak in the early Eocene. This Early Eocene Climate Optimum was followed by a 17 Myr cooling trend that led to the onset of Antarctic glaciation at the end of the Eocene. Several studies have examined the potential influence of perturbations to the sinks and sources of atmospheric carbon as mechanisms for the temperature drawdown over the Eocene. Examination of the changing magnitude of carbon sinks has focused on the importance of increased weathering associated with the uplift of the Tibetan plateau (Raymo and Ruddiman, 1992), the continental drift of basaltic provinces through the equatorial humid belt (Kent and Muttoni, 2013), or the emplacement of ophiolites during arc-continent collision in the face of a closing Tethys ocean (Jagoutz et al., 2016). With respect to carbon sources, the shutdown of Tethys subduction and related arc volcanism has been argued to significantly decrease carbon emissions and consequently global temperatures (Hoareau et al., 2015). In this study, we re-assess and quantify proposed atmospheric carbon sinks and sources to obtain an integrated picture of carbon flux changes over the Paleocene and Eocene and to estimate the relative importance of different mechanisms. To constrain carbon sources, we attempt to calculate the outgassing associated with large igneous provinces, mid-ocean ridges and volcanic arcs. We use plate reconstructions to track changes in length and divergence / convergence rates at plate boundaries as well as account for the onset and extinction of volcanic arcs. To constrain carbon sinks, we account for the sequestering of carbon due to silicate weathering and organic carbon burial. We again make use of plate reconstructions to trace highly weatherable arc systems and basaltic extrusions through the tropical humid belt and to assess the interplay between warmer Eocene

Earliest record of the fossil snake Palaeophis from the Paleocene/Eocene boundary in Denmark

DEFF Research Database (Denmark)

Kristensen, Hans Viborg; Cuny, Gilles; Redsted Rasmussen, Arne

2012-01-01

Abstract. – The earliest record of Palaeophis ever found in Denmark is here based on vertebrae described from the Paleocene/Eocene Stolleklint Clay of the Isle of Mors (northern Denmark). Although much smaller, they appear quite similar to the Eocene vertebra described from the Fur Formation...

Asian Eocene monsoons as revealed by leaf architectural signatures

Science.gov (United States)

Spicer, Robert A.; Yang, Jian; Herman, Alexei B.; Kodrul, Tatiana; Maslova, Natalia; Spicer, Teresa E. V.; Aleksandrova, Galina; Jin, Jianhua

2016-09-01

The onset and development of the Asian monsoon systems is a topic that has attracted considerable research effort but proxy data limitations, coupled with a diversity of definitions and metrics characterizing monsoon phenomena, have generated much debate. Failure of geological proxies to yield metrics capable of distinguishing between rainfall seasonality induced by migrations of the Inter-tropical Convergence Zone (ITCZ) from that attributable to topographically modified seasonal pressure reversals has frustrated attempts to understand mechanisms underpinning monsoon development and dynamics. Here we circumvent the use of such single climate parameter metrics in favor of detecting directly the distinctive attributes of different monsoon regimes encoded in leaf fossils. Leaf form adapts to the prevailing climate, particularly under the extreme seasonal stresses imposed by monsoons, so it is likely that fossil leaves carry a unique signature of past monsoon regimes. Leaf form trait spectra obtained from fossils from Eocene basins in southern China were compared with those seen in modern leaves growing under known climate regimes. The fossil leaf trait spectra, including those derived from previously published fossil floras from northwestern India, were most similar to those found in vegetation exposed to the modern Indonesia-Australia Monsoon (I-AM), which is largely a product of seasonal migrations of the ITCZ. The presence of this distinctive leaf physiognomic signature suggests that although a monsoon climate existed in Eocene time across southern Asia the characteristics of the modern topographically-enhanced South Asia Monsoon had yet to develop. By the Eocene leaves in South Asia had become well adapted to an I-AM type regime across many taxa and points to the existence of a pervasive monsoon climate prior to the Eocene. No fossil trait spectra typical of exposure to the modern East Asia monsoon were seen, suggesting the effects of this system in southern

Data Validation Package - June 2015 Groundwater and Surface Water Sampling at the Green River, Utah, Disposal Site

Energy Technology Data Exchange (ETDEWEB)

Linard, Joshua [USDOE Office of Legacy Management, Washington, DC (United States); Price, Jeffrey [Navarro Research and Engineering, Inc., Las Vegas, NV (United States)

2015-08-01

Groundwater samples were collected during the 2015 sampling event from point-of-compliance (POC) wells 0171, 0173, 0176, 0179, 0181, and 0813 to monitor the disposition of contaminants in the middle sandstone unit of the Cedar Mountain Formation. Groundwater samples also were collected from alluvium monitoring wells 0188, 0189, 0192, 0194, and 0707, and basal sandstone monitoring wells 0182, 0184, 0185, and 0588 as a best management practice. Surface locations 0846 and 0847 were sampled to monitor for degradation of water quality in the backwater area of Brown’s Wash and in the Green River immediately downstream of Brown’s Wash. The Green River location 0801 is upstream from the site and is sampled to determine background-threshold values (BTVs). Sampling and analyses were conducted as specified in Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated, http://energy.gov/lm/downloads/sampling-and- analysis-plan-us-department-energy-office-legacy-management-sites). Water levels were measured at each sampled well. The analytical data and associated qualifiers can be viewed in environmental database reports and are also available for viewing with dynamic mapping via the GEMS (Geospatial Environmental Mapping System) website at http://gems.lm.doe.gov/#. All six POC wells are completed in the middle sandstone unit of the Cedar Mountain Formation and are monitored to measure contaminant concentrations for comparison to proposed alternate concentration limits (ACLs), as provided in Table 1. Contaminant concentrations in the POC wells remain below their respective ACLs.

A redescription of Lithornis vulturinus (Aves, Palaeognathae) from the Early Eocene Fur Formation of Denmark.

Science.gov (United States)

Bourdon, Estelle; Lindow, Bent

2015-10-20

The extinct Lithornithidae include several genera and species of flying palaeognathous birds of controversial affinities known from the Early Paleogene of North America and Europe. An almost complete, articulated skeleton from the Early Eocene marine deposits of the Fur Formation (Denmark) was recently assigned to Lithornis vulturinus Owen, 1840. This study provides a detailed redescription and comparison of this three-dimensionally preserved specimen (MGUH 26770), which is one of the best preserved representatives of the Lithornithidae yet known. We suggest that some new features might be diagnostic of Lithornis vulturinus, including a pterygoid fossa shallower than in other species of Lithornis and the presence of a small caudal process on the os palatinum. We propose that Lithornis nasi (Harrison, 1984) is a junior synonym of Lithornis vulturinus and we interpret minor differences in size and shape among the specimens as intraspecific variation. To date, Lithornis vulturinus is known with certainty from the latest Paleocene-earliest Eocene to Early Eocene of the North Sea Basin (Ølst, Fur and London Clay Formations). Among the four species of the genus Lithornis, the possibility that Lithornis plebius Houde, 1988 (Early Eocene of Wyoming) is conspecific with either Lithornis vulturinus or Lithornis promiscuus Houde, 1988 (Early Eocene of Wyoming) is discussed. The presence of closely related species of Lithornis on either side of the North Atlantic in the Early Eocene reflects the existence of a high-latitude land connection between Europe and North America at that time.

Astronomical calibration of the middle Eocene Contessa Highway section (Gubbio, Italy)

Science.gov (United States)

Jovane, Luigi; Sprovieri, Mario; Coccioni, Rodolfo; Florindo, Fabio; Marsili, Andrea; Laskar, Jacques

2010-09-01

The Eocene climatic system experienced an important transition from warm Paleocene greenhouse to icehouse Oligocene conditions. This transition could first appear as a long-term cooling trend but, at an up-close look, this period is a complex combination of climatic events and, for most of them, causes and consequences are still not fully characterized. In this context, a study has been carried out on the middle Eocene sedimentary succession of the Contessa Highway section, central Italy, which is proposed as the Global Stratotype Section and Point (GSSP) for the Lutetian/Bartonian boundary at the top of the Chron 19n, with an astronomically calibrated age of 41.23 Ma. Through a cyclostratigraphic analysis of the rhythmic sedimentary alternations and combination with the results of time series analysis of the proxy record, we provide an orbital tuning of the middle Eocene and astronomical calibration of the bio-magnetostratigraphic events (particularly for the C19n/C18r Chron boundary) recognized at the Contessa Highway section.

High-resolution magneto stratigraphic of the Eocene-Oligocene boundary in the Umbria-Marche sequence; Stratigrafia magnetica ad alta risoluzione del limite Eocene-Oligocene nella successione Umbro-Marchigiana

Energy Technology Data Exchange (ETDEWEB)

Lanci, L.; Lowrie, W.; Montanari, A.

1998-12-31

High-resolution magneto stratigraphy across the Eocene-Olicene boundary has been employed in a detailed investigation of the nature of low-amplitude, short-wavelength oceanic magnetic anomalies. [Italiano] La stratigrafia magnetica ad alta risoluzione del limite Eocene-Oligocene ed il magnetismo delle rocce sono stati studiati in dettaglio per verificare la presenza di eventuali inversioni di polarita` brevi (short chrons) e variazioni delle intensita` del campo geomagnetico che possano essere messe in relazione con le anomalie oceaniche a bassa ampiezza e corto periodo.

Synergizing green and gray infrastructures to increase water supply resilience in the Brazos River basin in Texas

Science.gov (United States)

Gao, H.; Yamazaki, D.; Finley, T.; Bohn, T. J.; Low, G.; Sabo, J. L.

2017-12-01

Water infrastructure lies at the heart of the challenges and opportunities of Integrated Water Resource Management (IWRM). Green infrastructure (e.g., wetlands restoration) presents an alternative to its hard-path counterpart - gray infrastructure, which often has external, economic and unmeasured ecological costs. But the science framework to prioritize green infrastructure buildout is nascent. In this study, we addressed this gap in Brazos River basin in Texas, in the context of corporate decisions to secure water supplies for various water stewardship objectives. We developed a physically-based tool to quantify the potential for wetland restoration to restore desired flows (hydrology), and a financial framework for comparing its cost-benefit with heightening an existing dam (conservation finance). Our framework has three components. First, we harnessed a topographic index (HAND) to identify the potential wetlands sites. Second, we coupled a land surface model (VIC) with a hydrodynamic model (CaMa-Flood) to investigate the effects of wetland size, location, and vegetation on hydrology. Finally, we estimated the net present value, indirect rate of return and payback period for green (wetlands) vs. gray (reservoir expansion) infrastructure. We found wetlands have more substantial impact on peak flow than baseflow. Interestingly, wetlands can improve baseflow reliability but not directly except with the largest (>400 km2) projects. Peak flow reduction volumes of wetlands if used as credits towards reservoir flood-control storage provide adequate conservation storage to deliver guaranteed reliability of baseflow. Hence, the synergy of existing dams with newly created wetlands offers a promising natural solution to increase water supply resilience, while green projects also generate revenue compared to their gray counterparts. This study demonstrates the possibility of using innovative engineering design to synergize green and gray infrastructures to convert water

Late Eocene impact events recorded in deep-sea sediments

Science.gov (United States)

Glass, B. P.

1988-01-01

Raup and Sepkoski proposed that mass extinctions have occurred every 26 Myr during the last 250 Myr. In order to explain this 26 Myr periodicity, it was proposed that the mass extinctions were caused by periodic increases in cometary impacts. One method to test this hypothesis is to determine if there were periodic increases in impact events (based on crater ages) that correlate with mass extinctions. A way to test the hypothesis that mass extinctions were caused by periodic increases in impact cratering is to look for evidence of impact events in deep-sea deposits. This method allows direct observation of the temporal relationship between impact events and extinctions as recorded in the sedimentary record. There is evidence in the deep-sea record for two (possibly three) impact events in the late Eocene. The younger event, represented by the North American microtektite layer, is not associated with an Ir anomaly. The older event, defined by the cpx spherule layer, is associated with an Ir anomaly. However, neither of the two impact events recorded in late Eocene deposits appears to be associated with an unusual number of extinctions. Thus there is little evidence in the deep-sea record for an impact-related mass extinction in the late Eocene.

Preliminary analysis of the study of a Nuclear Energy Center at Green River, Utah

Energy Technology Data Exchange (ETDEWEB)

1979-03-01

The planning phase for the study of a conceptualized Regional Nuclear Energy Center (NEC) at Green River, Utah to serve a four state area is discussed and an outline of the proposed study is presented. It is assumed that the more technical issues of a NEC have already been studied in detail for generic sites and that this study will address the site specific impacts of a NEC at a representative site. The emphasis will be on the institutional, legal, political, sociological, economic and environmental impacts of a NEC. An assessment is made of the willingness and ability of related public and private entities to participate in the study. These include local, state and regional government agencies, colleges and universities, research organizations, private firms and consultants, and relevant federal agencies in Utah and the region.

Early-middle Eocene birds from the Lillebaelt Clay Formation of Denmark

DEFF Research Database (Denmark)

Lindow, Bent Erik Kramer

2009-01-01

The marine Lillebaelt Clay Formation of central Denmark is of early-middle Eocene age (late Ypresian - middle Lutetian; microfossil zones NP 13-NP 15). Over 20 bird fossils collected by amateur palaeontologists have been acquired through the Danish national ‘Danekrae' fossil treasure trove...... Clay Formation deposits derive from just after the Early Eocene Climate Optimum, a period of global elevated temperatures resulting from rapid greenhouse warming. Comparison between this bird assemblage and the recently revised assemblage from the older (earliest Ypresian) Fur Formation of Denmark...

Potential effects of four Flaming Gorge Dam hydropower operational scenarios on riparian vegetation of the Green River, Utah and Colorado

International Nuclear Information System (INIS)

LaGory, K.E.; Van Lonkhuyzen, R.A.

1995-06-01

Four hydropower operational scenarios at Flaming Gorge Dam were evaluated to determine their potential effects on riparian vegetation along the Green River in Utah and Colorado. Data collected in June 1992 indicated that elevation above the river had the largest influence on plant distribution. A lower riparian zone occupied the area between the approximate elevations of 800 and 4,200-cfs flows--the area within the range of hydropower operational releases. The lower zone was dominated by wetland plants such as cattail, common spikerush, coyote willow, juncus, and carex. An upper riparian zone was above the elevation of historical maximum power plant releases from the dam (4,200 cfs), and it generally supported plants adapted to mesic, nonwetland conditions. Common species in the upper zone included box elder, rabbitbrush, grasses, golden aster, and scouring rush. Multispectral aerial videography of the Green River was collected in May and June 1992 to determine the relationship between flow and the areas of water and the riparian zone. From these relationships, it was estimated that the upper zone would decrease in extent by about 5% with year-round high fluctuation, seasonally adjusted high fluctuation, and seasonally adjusted moderate fluctuation, but it would increase by about 8% under seasonally adjusted steady flow. The lower zone would increase by about 13% for both year-round and seasonally adjusted high fluctuation scenarios but would decrease by about 40% and 74% for seasonally adjusted moderate fluctuation and steady flows, respectively. These changes are considered to be relatively minor and would leave pre-dam riparian vegetation unaffected. Occasional high releases above power plant capacity would be needed for long-term maintenance of this relict vegetation

Post-Eocene tectonics of the Central Taurus Mountains

Directory of Open Access Journals (Sweden)

Ergün AKAY

1988-06-01

Full Text Available In post-Eocene time, the Central Taurus mountains have been subjected to four episodes of compression in probably Upper Eocene — Lower Oligocene, Langhian, Upper Tortonian, and Upper Pliocene to recent times. In the Upper Eocene — Lower Oligocene compressional period, Ecemiş, and Beyşehir conjugate faults which have both vertical and lateral components have been formed after an N - S compression. In the Langhian compression period, the Lycian nappes were emplaced from the NW to SE and this tectonic movement has also effected the Antalya and the Adana Miocene basins. In the Upper Tortonian compression period, firstly a WSW-ENE compression has resulted in the formation of Aksu thrust, Kırkkavak oblique reverse fault, Köprüçay syncline, Beşkonak anticline, Radyoring anticline, Taşağıl syncline and Kargı reverse faults. In this period a later phase of N — S compression has formed Çakallar folds, Gökçeler normal fault, the smooth anticline in Mut Karaman and the syncline in Ulukışla. In the latest compressional period from Upper Pliocene to recent, first on E — W compression which can be recognized by some mesoscopic faults has been developed and later a N — S compression resulted in the formation of the active faults on Ecemiş and Gökçeler faults, and the Antalya bay graben.

First South American Agathis (Araucariaceae), Eocene of Patagonia.

Science.gov (United States)

Wilf, Peter; Escapa, Ignacio H; Cúneo, N Rubén; Kooyman, Robert M; Johnson, Kirk R; Iglesias, Ari

2014-01-01

Agathis is an iconic genus of large, ecologically important, and economically valuable conifers that range over lowland to upper montane rainforests from New Zealand to Sumatra. Exploitation of its timber and copal has greatly reduced the genus's numbers. The early fossil record of Agathis comes entirely from Australia, often presumed to be its area of origin. Agathis has no previous record from South America. We describe abundant macrofossils of Agathis vegetative and reproductive organs, from early and middle Eocene rainforest paleofloras of Patagonia, Argentina. The leaves were formerly assigned to the New World cycad genus Zamia. Agathis zamunerae sp. nov. is the first South American occurrence and the most complete representation of Agathis in the fossil record. Its morphological features are fully consistent with the living genus. The most similar living species is A. lenticula, endemic to lower montane rainforests of northern Borneo. Agathis zamunerae sp. nov. demonstrates the presence of modern-aspect Agathis by 52.2 mya and vastly increases the early range and possible areas of origin of the genus. The revision from Zamia breaks another link between the Eocene and living floras of South America. Agathis was a dominant, keystone element of the Patagonian Eocene floras, alongside numerous other plant taxa that still associate with it in Australasia and Southeast Asia. Agathis extinction in South America was an integral part of the transformation of Patagonian biomes over millions of years, but the living species are disappearing from their ranges at a far greater rate.

Comparing particle-size distributions in modern and ancient sand-bed rivers

Science.gov (United States)

Hajek, E. A.; Lynds, R. M.; Huzurbazar, S. V.

2011-12-01

Particle-size distributions yield valuable insight into processes controlling sediment supply, transport, and deposition in sedimentary systems. This is especially true in ancient deposits, where effects of changing boundary conditions and autogenic processes may be detected from deposited sediment. In order to improve interpretations in ancient deposits and constrain uncertainty associated with new methods for paleomorphodynamic reconstructions in ancient fluvial systems, we compare particle-size distributions in three active sand-bed rivers in central Nebraska (USA) to grain-size distributions from ancient sandy fluvial deposits. Within the modern rivers studied, particle-size distributions of active-layer, suspended-load, and slackwater deposits show consistent relationships despite some morphological and sediment-supply differences between the rivers. In particular, there is substantial and consistent overlap between bed-material and suspended-load distributions, and the coarsest material found in slackwater deposits is comparable to the coarse fraction of suspended-sediment samples. Proxy bed-load and slackwater-deposit samples from the Kayenta Formation (Lower Jurassic, Utah/Colorado, USA) show overlap similar to that seen in the modern rivers, suggesting that these deposits may be sampled for paleomorphodynamic reconstructions, including paleoslope estimation. We also compare grain-size distributions of channel, floodplain, and proximal-overbank deposits in the Willwood (Paleocene/Eocene, Bighorn Basin, Wyoming, USA), Wasatch (Paleocene/Eocene, Piceance Creek Basin, Colorado, USA), and Ferris (Cretaceous/Paleocene, Hanna Basin, Wyoming, USA) formations. Grain-size characteristics in these deposits reflect how suspended- and bed-load sediment is distributed across the floodplain during channel avulsion events. In order to constrain uncertainty inherent in such estimates, we evaluate uncertainty associated with sample collection, preparation, analytical

Eocene crabs (Crustacea, Brachyura) from Bonaire, Netherlands Antilles

NARCIS (Netherlands)

Collins, J.H.S.; Donovan, S.K.

2005-01-01

Recently discovered crabs from the Middle to Upper Eocene of northern Bonaire, Netherlands Antilles, include well-preserved carapaces of Montezumella rutteni Van Straelen, originally described from an incomplete holotype. The more comprehensive description of this species provided herein includes

Persistent near-tropical warmth on the Antarctic continent during the early Eocene epoch.

Science.gov (United States)

Pross, Jörg; Contreras, Lineth; Bijl, Peter K; Greenwood, David R; Bohaty, Steven M; Schouten, Stefan; Bendle, James A; Röhl, Ursula; Tauxe, Lisa; Raine, J Ian; Huck, Claire E; van de Flierdt, Tina; Jamieson, Stewart S R; Stickley, Catherine E; van de Schootbrugge, Bas; Escutia, Carlota; Brinkhuis, Henk

2012-08-02

The warmest global climates of the past 65 million years occurred during the early Eocene epoch (about 55 to 48 million years ago), when the Equator-to-pole temperature gradients were much smaller than today and atmospheric carbon dioxide levels were in excess of one thousand parts per million by volume. Recently the early Eocene has received considerable interest because it may provide insight into the response of Earth's climate and biosphere to the high atmospheric carbon dioxide levels that are expected in the near future as a consequence of unabated anthropogenic carbon emissions. Climatic conditions of the early Eocene 'greenhouse world', however, are poorly constrained in critical regions, particularly Antarctica. Here we present a well-dated record of early Eocene climate on Antarctica from an ocean sediment core recovered off the Wilkes Land coast of East Antarctica. The information from biotic climate proxies (pollen and spores) and independent organic geochemical climate proxies (indices based on branched tetraether lipids) yields quantitative, seasonal temperature reconstructions for the early Eocene greenhouse world on Antarctica. We show that the climate in lowland settings along the Wilkes Land coast (at a palaeolatitude of about 70° south) supported the growth of highly diverse, near-tropical forests characterized by mesothermal to megathermal floral elements including palms and Bombacoideae. Notably, winters were extremely mild (warmer than 10 °C) and essentially frost-free despite polar darkness, which provides a critical new constraint for the validation of climate models and for understanding the response of high-latitude terrestrial ecosystems to increased carbon dioxide forcing.

Late Eocene white pines (Pinus subgenus Strobus) from southern China.

Science.gov (United States)

Xu, Qingqing; Zhou, Wenjun; Kodrul, Tatiana M; Naugolnykh, Serge V; Jin, Jianhua

2015-11-09

Fossil records indicate that the genus Pinus L. split into two subgenera by the Late Cretaceous, although subgenus Strobus (D. Don) Lemmon is less well documented than subgenus Pinus L., especially in eastern Asia. In this paper, Pinus maomingensis sp. nov. is established based on a compressed seed cone from the upper Eocene of the Maoming Basin of southern China. This species is attributed to genus Pinus, subgenus Strobus, section Quinquefoliae Duhamel, subsection Strobus Loudon based on the combination of morphological characters obtained from the cone scales, specifically from the terminal umbo, rhombic apophysis, and cuticle structure. Associated fascicles of needle leaves with deciduous sheaths and bulbous bases are recognized as Pinus sp. and also represent Pinus subgenus Strobus. This new discovery from the Maoming Basin constitutes the first megafossil record of subgenus Strobus from southern China and implies that the members of this subgenus arrived in the southern region of China by the late Eocene. The extant species of subgenus Strobus are mainly distributed in northern temperate and tropical to subtropical mountainous regions. We propose that the Maoming Basin was adjacent to a mountainous region during the late Eocene.

CRUSTOSE CORALLINE ALGAL PAVEMENTS FROM LATE EOCENE COLLI BERICI OF NORTHERN ITALY

OpenAIRE

BASSI, DAVIDE

2017-01-01

The Eocene from the Prealpine region records the first phase of the crustose coralline algae flourishing in the Cenozoic. These algae are very frequent in the Marne di Priabona Formation (Late Eocene). This palaeoecological research involves ourcrop at Barbarano Vicentino(Vicenza) in the Colli Berici which is well known for its Paleogene stratigraphy. The coralline unit consists of a floatstone bank 6 m thick with rhodoliths and laminar crusts; it lies between macroforaminifer dominated limes...

Atmospheric pCO2 reconstructed across five early Eocene global warming events

Science.gov (United States)

Cui, Ying; Schubert, Brian A.

2017-11-01

Multiple short-lived global warming events, known as hyperthermals, occurred during the early Eocene (56-52 Ma). Five of these events - the Paleocene-Eocene Thermal Maximum (PETM or ETM1), H1 (or ETM2), H2, I1, and I2 - are marked by a carbon isotope excursion (CIE) within both marine and terrestrial sediments. The magnitude of CIE, which is a function of the amount and isotopic composition of carbon added to the ocean-atmosphere system, varies significantly between marine versus terrestrial substrates. Here we use the increase in carbon isotope fractionation by C3 land plants in response to increased pCO2 to reconcile this difference and reconstruct a range of background pCO2 and peak pCO2 for each CIE, provided two potential carbon sources: methane hydrate destabilization and permafrost-thawing/organic matter oxidation. Although the uncertainty on each pCO2 estimate using this approach is low (e.g., median uncertainty = + 23% / - 18%), this work highlights the potential for significant systematic bias in the pCO2 estimate resulting from sampling resolution, substrate type, diagenesis, and environmental change. Careful consideration of each of these factors is required especially when applying this approach to a single marine-terrestrial CIE pair. Given these limitations, we provide an upper estimate for background early Eocene pCO2 of 463 +248/-131 ppmv (methane hydrate scenario) to 806 +127/-104 ppmv (permafrost-thawing/organic matter oxidation scenario). These results, which represent the first pCO2 proxy estimates directly tied to the Eocene hyperthermals, demonstrate that early Eocene warmth was supported by background pCO2 less than ∼3.5× preindustrial levels and that pCO2 > 1000 ppmv may have occurred only briefly, during hyperthermal events.

Synchronous turnover of flora, fauna, and climate at the Eocene-Oligocene Boundary in Asia.

Science.gov (United States)

Sun, Jimin; Ni, Xijun; Bi, Shundong; Wu, Wenyu; Ye, Jie; Meng, Jin; Windley, Brian F

2014-12-12

The Eocene-Oligocene Boundary (~34 million years ago) marks one of the largest extinctions of marine invertebrates in the world oceans and of mammalian fauna in Europe and Asia in the Cenozoic era. A shift to a cooler climate across this boundary has been suggested as the cause of this extinction in the marine environment, but there is no manifold evidence for a synchronous turnover of flora, fauna and climate at the Eocene-Oligocene Boundary in a single terrestrial site in Asia to support this hypothesis. Here we report new data of magnetostratigraphy, pollen and climatic proxies in the Asian interior across the Eocene-Oligocene Boundary; our results show that climate change forced a turnover of flora and fauna, suggesting there was a change from large-size perissodactyl-dominant fauna in forests under a warm-temperate climate to small rodent/lagomorph-dominant fauna in forest-steppe in a dry-temperate climate across the Eocene-Oligocene Boundary. These data provide a new terrestrial record for this significant Cenozoic environmental event.

A green roof grant program for Washington DC

International Nuclear Information System (INIS)

Johnson, P.A.

2007-01-01

The Chesapeake Bay Foundation (CBF) began its green roof demonstration project with $300,000 in funding provided by the DC Water and Sewer Authority. This paper reviewed the history of the project, its goals and early findings. The main objective was to demonstrate the technical, policy and economic feasibility of installing green roofs on commercial buildings in Washington DC and to promote green roofs as a means to manage storm water and improve water quality through the reduction of excessive runoff. The CBF has issued grants for the installation of 7 green roofs varying in size, design, location, and use. The projects included both new and existing structures designed to improve storm-water management in an urban area with significant pollution stress on the adjacent rivers. This paper provided technical, cost, and performance evaluations of each roof. A public outreach segment provided information to decision-makers to encourage more widespread replication of green roof technology throughout the metropolitan area. Much of the District of Columbia is served by a combined sewer system that becomes overloaded and discharges raw sewage into adjacent rivers during even moderately heavy rains. An average of 75 overflow events each year result in 1.5 billion gallons discharged into the Anacostia River. The installation of green roofs on buildings in the combined sewer area would retain storm water during these heavy rains and reduce the amount of overflow discharges. Apartments, as well as commercial and government buildings with mostly flat roofs are the most likely candidates for green roofs. The demonstration roofs are intended to become models, which all building owners could use as a guide for future plans for construction or re-construction to expand green roof coverage in Washington DC. It was emphasized that although such large-scale replication will take time and financial investments, it is achievable given enough political will and commercial awareness of

Fossil evidence of wing shape in a stem relative of swifts and hummingbirds (Aves, Pan-Apodiformes).

Science.gov (United States)

Ksepka, Daniel T; Clarke, Julia A; Nesbitt, Sterling J; Kulp, Felicia B; Grande, Lance

2013-06-22

A feathered specimen of a new species of Eocypselus from the Early Eocene Green River Formation of Wyoming provides insight into the wing morphology and ecology in an early part of the lineage leading to extant swifts and hummingbirds. Combined phylogenetic analysis of morphological and molecular data supports placement of Eocypselus outside the crown radiation of Apodiformes. The new specimen is the first described fossil of Pan-Apodiformes from the pre-Pleistocene of North America and the only reported stem taxon with informative feather preservation. Wing morphology of Eocypselus rowei sp. nov. is intermediate between the short wings of hummingbirds and the hyper-elongated wings of extant swifts, and shows neither modifications for the continuous gliding used by swifts nor modifications for the hovering flight style used by hummingbirds. Elongate hindlimb elements, particularly the pedal phalanges, also support stronger perching capabilities than are present in Apodiformes. The new species is the smallest bird yet described from the Green River Formation, and supports the hypothesis that a decrease in body size preceded flight specializations in Pan-Apodiformes. The specimen also provides the first instance of melanosome morphology preserved in association with skeletal remains from the Green River Formation.

Astronomical calibration of the geological timescale: closing the middle Eocene gap

Science.gov (United States)

Westerhold, T.; Röhl, U.; Frederichs, T.; Bohaty, S. M.; Zachos, J. C.

2015-09-01

To explore cause and consequences of past climate change, very accurate age models such as those provided by the astronomical timescale (ATS) are needed. Beyond 40 million years the accuracy of the ATS critically depends on the correctness of orbital models and radioisotopic dating techniques. Discrepancies in the age dating of sedimentary successions and the lack of suitable records spanning the middle Eocene have prevented development of a continuous astronomically calibrated geological timescale for the entire Cenozoic Era. We now solve this problem by constructing an independent astrochronological stratigraphy based on Earth's stable 405 kyr eccentricity cycle between 41 and 48 million years ago (Ma) with new data from deep-sea sedimentary sequences in the South Atlantic Ocean. This new link completes the Paleogene astronomical timescale and confirms the intercalibration of radioisotopic and astronomical dating methods back through the Paleocene-Eocene Thermal Maximum (PETM, 55.930 Ma) and the Cretaceous-Paleogene boundary (66.022 Ma). Coupling of the Paleogene 405 kyr cyclostratigraphic frameworks across the middle Eocene further paves the way for extending the ATS into the Mesozoic.

Astronomically-Forced Lake Expansion and Contraction Cycles: Sr Isotopic Evidence from the Eocene Green River Formation, Western USA

Science.gov (United States)

Baddouh, M.; Meyers, S. R.; Carroll, A.; Beard, B. L.; Johnson, C.

2014-12-01

87Sr/86Sr ratio from ancient lake deposits offer a unique insight into the astronomical forcing of lake expansion and contraction, by recording changes in runoff/groundwater provenance. We present new high-resolution 87Sr/86Sr data from the upper Wilkins Peak Member, to investigate linkages between astronomical forcing, water sources, and lake level in a classic rhythmic succession. Fifty-one 87Sr/86Sr ratios from White Mountain core #1 were acquired with a sampling interval of ~30 cm starting from the top of alluvial "I" bed to the lower Laney Member. The 87Sr/86Sr data show a strong and significant negative correlation with oil-yield, a traditional proxy for paleolake level and organic productivity. Application of a radioisotopic time scale, using previously dated ash beds, reveals that both 87Sr/86Sr and oil yield have a strong 20 kyr rhythm. The 87Sr/86Sr data more clearly express a longer period 100 kyr signal, similar to the Laskar 10D eccentricity solution. Using our nominal radioisotopic time scale, the Laskar 10D solution and 87Sr/86Sr data suggest that highest lake levels and greatest organic enrichment are attained during greatest precession and eccentricity. Regional geologic studies and modern river water analyses have shown that less radiogenic waters mostly originate west of the basin, where drainage is strongly influenced by thick Paleozoic and Mesozoic marine carbonate units. Decreased in 87Sr/86Sr therefore imply greater relative water contributions from the Sevier orogenic highlands, relative to lower relief, more radiogenic ranges lying to the east. We therefore propose that highstands of Lake Gosiute record increased penetration of Pacific moisture, related either to increased El Niño frequency or southward displacement of major storm tracks. We hypothesize that the occurrence of wetter winters caused expansion of Lake Gosiute, deposition of organic carbon rich facies, and decreased lake water 87Sr/86Sr.

Atmospheric pCO2 Reconstructed across the Early Eocene Hyperthermals

Science.gov (United States)

Cui, Y.; Schubert, B.

2015-12-01

Negative carbon isotope excursions (CIEs) are commonly associated with extreme global warming. The Early Eocene is punctuated by five such CIEs, the Paleocene-Eocene thermal maximum (PETM, ca. 55.8 Ma), H1 (ca. 53.6 Ma), H2 (ca. 53.5 Ma), I1 (ca. 53.3 Ma), and I2 (ca. 53.2 Ma), each characterized by global warming. The negative CIEs are recognized in both marine and terrestrial substrates, but the terrestrial substrates exhibit a larger absolute magnitude CIE than the marine substrates. Here we reconcile the difference in CIE magnitude between the terrestrial and marine substrates for each of these events by accounting for the additional carbon isotope fractionation by C3 land plants in response to increased atmospheric pCO2. Our analysis yields background and peak pCO2 values for each of the events. Assuming a common mechanism for each event, we calculate that background pCO2 was not static across the Early Eocene, with the highest background pCO2 immediately prior to I2, the last of the five CIEs. Background pCO2 is dependent on the source used in our analysis with values ranging from 300 to 720 ppmv provided an injection of 13C-depleted carbon with δ13C value of -60‰ (e.g. biogenic methane). The peak pCO2 during each event scales according to the magnitude of CIE, and is therefore greatest during the PETM and smallest during H2. Both background and peak pCO2 are higher if we assume a mechanism of permafrost thawing (δ13C = -25‰). Our reconstruction of pCO2 across these events is consistent with trends in the δ18O value of deep-sea benthic foraminifera, suggesting a strong link between pCO2 and temperature during the Early Eocene.

Diatom and silicoflagellate biostratigraphy for the late Eocene: ODP 1090 (sub-Antarctic Atlantic)

Science.gov (United States)

Barron, John A.; Bukry, David B.; Gersonde, Rainer

2014-01-01

Abundant and well-preserved diatoms and silicofl agellate assemblages are documented through a complete late Eocene sequence, ODP Hole 1090B, recovered from the southern Agulhas Ridge in the sub-Antarctic South Atlantic. A sequence of Cestodiscus (diatom) species occurrence events involving C. pulchellus var. novazealandica, C. fennerae, C. antarcticus, C. convexus, C. trochus, and C. robustus is tied with paleomagnetic stratigraphy and provides the basis of proposing a new diatom zonation for the latest middle Eocene to early Oligocene (~37.6–33.4 Ma) of the sub-Antarctic South Atlantic. Comparison with previously published diatom occurrence charts suggested this zonation should be applicable throughout the low latitude regions of the world’s oceans. Silicofl agellates belong to the Dictyocha hexacantha and the overlying Corbisema apiculata Zones. The late Eocene succession of silicofl agellate species is dominated by Naviculopsis (20–60%). Naviculopsis constricta and N. foliacea dominate the D. hexacantha Zone, followed by the N. constricta, then N. biapiculata in the C. apiculata Zone. Cold-water Distephanus is most abundant in the latest Eocene along with N. biapiculata. The tops of zonal guide fossils Dictyocha hexacantha and Hannaites quadria (both 36.6 Ma) and Dictyocha spinosa (37.1 Ma) are tied with paleomagnetic stratigraphy.

Exploration potential of the Eocene deposits in central Romanian block sea off shore

International Nuclear Information System (INIS)

Tambrea, D; Raileanu, A; Barbuliceanu, N; Borosi, V.

2002-01-01

Full text:The study area comprises the Eocene Istria Depression bounded by Peceneaga- Camena and Heracleea faults, in front of North Dobrogea Orogene and Central Dobrogea, in the Romanian Black Sea offshore. The analysis of 100 two- dimensional (2D) seismic lines and two- three dimensional (3D) seismic surveys and well data has permitted to outline that the geo dynamic evolution of Eocene basins has led to the deposition of carbonate- sliciclastic turbidity, porous carbonate shelf margin reservoir deposits, and muddy carbonate turbiditic source rocks that present new Eocene petroleum targets. The main Eocene sub basin located in Iris-Venus area is deep, rhombic shaped, del imitated by normal faults, and may be connected with the strike-slip deformation component of Peceneaga- Camena fault. The next sub basin, located on West Lebeda area may be considered a cross- fault extensional zone. In the following sub basin East Lebada- Minerva area, normal faults generated a tectonic corridor characterized by high subsidence rate and local submarine/sub aerial intra slope topographic high. The last sub basin localized in Histria is a ponded one and captured highly organic matter rich muddly carbonate turgidities. In all sub basins, there is a progression from structure control to sediment control deposition

Precipitation Reconstructions and Periods of Drought in the Upper Green River Basin, Wyoming, USA

Science.gov (United States)

Follum, M.; Barnett, A.; Bellamy, J.; Gray, S.; Tootle, G.

2008-12-01

Due to recent drought and stress on water supplies in the Colorado River Compact States, more emphasis has been placed on the study of water resources in the Upper Green River Basin (UGRB) of Wyoming, Utah, and Colorado. The research described here focuses on the creation of long-duration precipitation records for the UGRB using tree-ring chronologies. When combined with existing proxy streamflow reconstructions and drought frequency analysis, these records offer a detailed look at hydrologic variability in the UGRB. Approximately thirty-three existing tree ring chronologies were analyzed for the UGRB area. Several new tree ring chronologies were also developed to enhance the accuracy and the geographical diversity of the resulting tree-ring reconstructions. In total, three new Douglas-fir (Pseudotsuga menziesii) and four new limber pine (Pinus flexilis) sites were added to the available tree-ring chronologies in this area. Tree-ring based reconstructions of annual (previous July through current June) precipitation were then created for each of the seventeen sub-watersheds in the UGRB. Reconstructed precipitation records extend back to at least 1654 AD, with reconstructions for some sub-basins beginning pre-1500. Variance explained (i.e. adjusted R2) ranged from 0.41 to 0.74, and the reconstructions performed well in a variety of verification tests. Additional analyses focused on stochastic estimation of drought frequency and return period, and detailed comparisons between reconstructed records and instrumental observations. Overall, this work points to the prevalence of severe, widespread drought in the UGRB. These analyses also highlight the relative wetness and lack of sustained dry periods during the instrumental period (1895-Present). Such long- term assessments are, in turn, vital tools as the Compact States contemplate the "Law of the River" in the face of climate change and ever-growing water demands.

Isolation and Characterization of Blue Green Algae from Egyptian ...

African Journals Online (AJOL)

meldemellawy

2014-02-20

Feb 20, 2014 ... aminotransferase (AMT) domains of the mycE and ndaF genes (Jungblut et al., 2006) allowing detection of microcystin and nodularin-producing cyanobacteria. MATERIALS AND METHODS. Isolation and cultivation of blue green algae. Blue green algae had been isolated from soil of Rice field in river.

Fission track dating of tuffaceous eocene formations of the North Bakony Mountains (Transdanubia, Hungary)

International Nuclear Information System (INIS)

Dunkl, I.

1990-01-01

Fission track dating was performed in accessory minerals of strongly altered, clay mineralized tuffite strata lying in the upper part of the Eocene sequence of the North Bakony Mountains. The homogeneity of the fission track (FT) ages measured on apatite and zircon refers only to insignificant redeposition, no remarkable mingling of the detrital matter vould be stated. The average of the FT-ages falls to the Bartonian, into the time interval determined by nannoplankton guide horizons for the volcanic activity (41.9 ± 4.1 Ma). As to their biostratigraphic age the Middle Eocene samples show an FT-average of 44.2 ± 3.4 Ma, the average of the Upper Eocene group is 39.9 ± 4.1 Ma. The difference between the two groups refers to the two phases of the volcanic activity. The first maximum of volcanism generated the Upper Lutetian to Bartonian glauconitic sequence while the second maximum at the Bartonian-Priabonian boundary produced the tuff strata. The strata in the neighbouring areas relate to continuous volcanism in the Upper Eocene, in the studied area, however, the upper part of the Priabonian was eroded. (author) 51 refs.; 4 figs.; 1 tab

Anatomy of a mountain: The Thebes Limestone Formation (Lower Eocene) at Gebel Gurnah, Luxor, Nile Valley, Upper Egypt

Science.gov (United States)

King, Christopher; Dupuis, Christian; Aubry, Marie-Pierre; Berggren, William A.; Knox, Robert O.'B.; Galal, Wael Fathi; Baele, Jean-Marc

2017-12-01

We present a detailed geologic study of the Thebes Formation at Gebel Gurnah in its locus typicus on the West Bank (opposite Luxor) of the Nile River in the Upper Nile Valley, Egypt. This is the first detailed measurement and lithologic description of the ∼340 m thick (predominantly) carbonate section. The Thebes Formation is divided into thirteen major lithic units (A to M). We interpret data on the lithologic succession and variations, whole rock/clay mineralogy, and macro/micropaleontology in terms of deposition on a shallow carbonate platform episodically influenced by continental runoff, and describe six depositional sequences that we place in the global framework of Lower Eocene (Ypresian) sequence stratigraphy. We note however significant incompatibilities between the Thebes depositional sequences and the global sequences. We emend the definition of the Thebes Formation by defining its top as corresponding to level 326 m at the top of Nodular Limestone 'L' (NLL), and assigning the overlying beds to the Minia Limestone Formation. New biostratigraphic data and revision of previous studies establish the direct assignment of the Thebes Formation to planktonic foraminiferal Zones E4/P6b (upper part), E5/P7 and (indirectly) Zone E6/P8, and (probably, indirectly) Zone E7a/;P9;, and to calcareous nannofossil Zone NP12 and lower Zone NP13 of the Lower Eocene (Ypresian) and provide a temporal framework spanning ∼ 2.8 Myr from towards the end of the Early Eocene. Dominantly carbonate deposition, with a strongly reduced detrital influx, occurred on a very wide shelf (probably) at least ∼ 100 km from the coastline. The thick sedimentary succession and the marked vertical lithologic variations are interpreted as resulting from sea level fluctuations imprinted on a long-term decrease in sea-level associated with rapid subsidence reflecting tectonic relaxation after the major Late Paleocene tectonic reorganization of the Syrian Arc.

Evidence of Late Palaeocene-Early Eocene equatorial rain forest ...

Indian Academy of Sciences (India)

Prakash

2009-11-02

Nov 2, 2009 ... influx of CO2 during early Cenozoic times (Kent and Muttoni. 2008), besides ... Palaeocene – Eocene lignite and coal deposits of India. .... journey of the Indian subcontinent and massive outpouring ..... ice age (Plana 2004).

A Model-Model and Data-Model Comparison for the Early Eocene Hydrological Cycle

Science.gov (United States)

Carmichael, Matthew J.; Lunt, Daniel J.; Huber, Matthew; Heinemann, Malte; Kiehl, Jeffrey; LeGrande, Allegra; Loptson, Claire A.; Roberts, Chris D.; Sagoo, Navjit; Shields, Christine

2016-01-01

A range of proxy observations have recently provided constraints on how Earth's hydrological cycle responded to early Eocene climatic changes. However, comparisons of proxy data to general circulation model (GCM) simulated hydrology are limited and inter-model variability remains poorly characterised. In this work, we undertake an intercomparison of GCM-derived precipitation and P - E distributions within the extended EoMIP ensemble (Eocene Modelling Intercomparison Project; Lunt et al., 2012), which includes previously published early Eocene simulations performed using five GCMs differing in boundary conditions, model structure, and precipitation-relevant parameterisation schemes. We show that an intensified hydrological cycle, manifested in enhanced global precipitation and evaporation rates, is simulated for all Eocene simulations relative to the preindustrial conditions. This is primarily due to elevated atmospheric paleo-CO2, resulting in elevated temperatures, although the effects of differences in paleogeography and ice sheets are also important in some models. For a given CO2 level, globally averaged precipitation rates vary widely between models, largely arising from different simulated surface air temperatures. Models with a similar global sensitivity of precipitation rate to temperature (dP=dT ) display different regional precipitation responses for a given temperature change. Regions that are particularly sensitive to model choice include the South Pacific, tropical Africa, and the Peri-Tethys, which may represent targets for future proxy acquisition. A comparison of early and middle Eocene leaf-fossil-derived precipitation estimates with the GCM output illustrates that GCMs generally underestimate precipitation rates at high latitudes, although a possible seasonal bias of the proxies cannot be excluded. Models which warm these regions, either via elevated CO2 or by varying poorly constrained model parameter values, are most successful in simulating a

Modifications to the remedial action plan and site design for stabilization of the inactive Uranium Mill Tailings Site at Green River, Utah

International Nuclear Information System (INIS)

1994-09-01

Modifications to the water resources protection strategy detailed in the remedial action plan for the Green River, Utah, disposal site are presented. The modifications are based on new information, including ground water quality data collected after remedial action was completed and on a revised assessment of disposal cell design features, surface conditions, and site hydrogeology. The modifications will result in compliance with the U.S. EPA proposed ground water standards (52 FR 36000 (1987))

Fossil cyclanthus (cyclanthaceae, pandanales) from the eocene of Germany and England.

Science.gov (United States)

Smith, Selena Y; Collinson, Margaret E; Rudall, Paula J

2008-06-01

The first known fossil fruits and seeds of Cyclanthaceae are described here. Cyclanthus messelensis sp. nov., from the Middle Eocene of Messel, Germany, has discoidal fruiting cycles up to 6 cm in diameter, with a central hole, radiating fiber strands, a thickened outer rim, and paratetracytic stomata. In situ seeds are up to 2 mm long, with an elongate micropylar end, a chalazal neck, and adpressed bands. The Messel fruits and seeds are nearly identical to those of Cyclanthus, differing in minor details of cuticular structure and seeds. The exceptional preservation at Messel (including in situ and isolated seeds) has also allowed us to establish the taxonomic affinity of isolated seeds ('Scirpus' lakensis) that are spatially and temporally widespread in the late Early and early Middle Eocene of southern England. Cyclanthus lakensis comb. nov. is described here as a morphotaxon for isolated fossil Cyclanthus seeds, preserved only as cuticular envelopes. Cyclanthus is another example of links between Eocene Europe and Recent South American floras because it is found today only from Mexico to South America. This material represents the first fossil fruits and seeds of Cyclanthus, which clearly was once growing in the Paleogene of the Old World.

Body size and premolar evolution in the early-middle eocene euprimates of Wyoming.

Science.gov (United States)

Jones, Katrina E; Rose, Kenneth D; Perry, Jonathan M G

2014-01-01

The earliest euprimates to arrive in North America were larger-bodied notharctids and smaller-bodied omomyids. Through the Eocene, notharctids generally continued to increase in body size, whereas omomyids generally radiated within small- and increasingly mid-sized niches in the middle Eocene. This study examines the influence of changing body size and diet on the evolution of the lower fourth premolar in Eocene euprimates. The P4 displays considerable morphological variability in these taxa. Despite the fact that most studies of primate dental morphology have focused on the molars, P4 can also provide important paleoecological insights. We analyzed the P4 from 177 euprimate specimens, representing 35 species (11 notharctids and 24 omomyids), in three time bins of approximately equal duration: early Wasatchian, late Wasatchian, and Bridgerian. Two-dimensional surface landmarks were collected from lingual photographs, capturing important variation in cusp position and tooth shape. Disparity metrics were calculated and compared for the three time bins. In the early Eocene, notharctids have a more molarized P4 than omomyids. During the Bridgerian, expanding body size range of omomyids was accompanied by a significant increase in P4 disparity and convergent evolution of the semimolariform condition in the largest omomyines. P4 morphology relates to diet in early euprimates, although patterns vary between families. Copyright © 2013 Wiley Periodicals, Inc.

Scaled biotic disruption during early Eocene global warming events

NARCIS (Netherlands)

Gibbs, S.J.; Bown, P.R.; Murphy, B.H.; Sluijs, A.; Edgar, K.M.; Pälike, H.; Bolton, C.T.; Zachos, J.C.

2012-01-01

Late Paleocene and early Eocene hyperthermals are transient warming events associated with massive perturbations of the global carbon cycle, and are considered partial analogues for current anthropogenic climate change. Because the magnitude of carbon release varied between the events, they are

Assessment of dissolved-solids loading to the Colorado River in the Paradox Basin between the Dolores River and Gypsum Canyon, Utah

Science.gov (United States)

Shope, Christopher L.; Gerner, Steven J.

2014-01-01

Salinity loads throughout the Colorado River Basin have been a concern over recent decades due to adverse impacts on population, natural resources, and regional economics. With substantial financial resources and various reclamation projects, the salt loading to Lake Powell and associated total dissolved-solids concentrations in the Lower Colorado River Basin have been substantially reduced. The Colorado River between its confluence with the Dolores River and Lake Powell traverses a physiographic area where saline sedimentary formations and evaporite deposits are prevalent. However, the dissolved-solids loading in this area is poorly understood due to the paucity of water-quality data. From 2003 to 2011, the U.S. Geological Survey in cooperation with the U.S. Bureau of Reclamation conducted four synoptic sampling events to quantify the salinity loading throughout the study reach and evaluate the occurrence and impacts of both natural and anthropogenic sources. The results from this study indicate that under late-summer base-flow conditions, dissolved-solids loading in the reach is negligible with the exception of the Green River, and that variations in calculated loads between synoptic sampling events are within measurement and analytical uncertainties. The Green River contributed approximately 22 percent of the Colorado River dissolved-solids load, based on samples collected at the lower end of the study reach. These conclusions are supported by water-quality analyses for chloride and bromide, and the results of analyses for the stable isotopes of oxygen and deuterium. Overall, no significant sources of dissolved-solids loading from tributaries or directly by groundwater discharge, with the exception of the Green River, were identified in the study area.

Arctic Ocean circulation during the anoxic Eocene Azolla event

Science.gov (United States)

Speelman, Eveline; Sinninghe Damsté, Jaap; März, Christian; Brumsack, Hans; Reichart, Gert-Jan

2010-05-01

through seawater inflow). Excess vanadium accumulation during the Azolla event (80 ppm), basin volume and surface area, average vanadium sea (1.8 ppb) and river water (1.0 ppb) concentrations, together indicate that an inflow of Nordic Sea water of 0.2 Sv is needed to sustain vanadium levels. The same calculation using molybdenum gives an inflow of only 0.02 Sv. These low inflow rates imply Arctic Ocean (deep) water residence times of 2000 - 20000 years, respectively. Based on climate modeling we calculated a summed net amount of precipitation for the Eocene Arctic Basin (Precipitation - Evaporation + Runoff) of 0.46 Sv. Together these notions indicate that a compensating inflow of saline North Atlantic water occurred, accompanied by an outflow of more fresh waters, resulting in a bi-directional, two-layer flow through the (proto-) Fram Strait. Consequently, the limited exchange of water through the Fram Strait implies that a relatively low export productivity would have been sufficient to render Arctic bottom waters anoxic. Jakobsson, M., Backman, J., Rudels, B., Nycander, J., Frank, M., Mayer, L., Jokat, W., Sangiorgi, F., O'Regan, M., Brinkhuis, H., King, J., Moran, K. (2007). The early Miocene onset of a ventilated circulation regimen in the Arctic Ocean. Nature 447, 986-990.

Southern ocean warming, sea level and hydrological change during the Paleocene-Eocene thermal maximum

Directory of Open Access Journals (Sweden)

A. Sluijs

2011-01-01

Full Text Available A brief (~150 kyr period of widespread global average surface warming marks the transition between the Paleocene and Eocene epochs, ~56 million years ago. This so-called "Paleocene-Eocene thermal maximum" (PETM is associated with the massive injection of ¹³C-depleted carbon, reflected in a negative carbon isotope excursion (CIE. Biotic responses include a global abundance peak (acme of the subtropical dinoflagellate Apectodinium. Here we identify the PETM in a marine sedimentary sequence deposited on the East Tasman Plateau at Ocean Drilling Program (ODP Site 1172 and show, based on the organic paleothermometer TEX₈₆, that southwest Pacific sea surface temperatures increased from ~26 °C to ~33°C during the PETM. Such temperatures before, during and after the PETM are >10 °C warmer than predicted by paleoclimate model simulations for this latitude. In part, this discrepancy may be explained by potential seasonal biases in the TEX₈₆ proxy in polar oceans. Additionally, the data suggest that not only Arctic, but also Antarctic temperatures may be underestimated in simulations of ancient greenhouse climates by current generation fully coupled climate models. An early influx of abundant Apectodinium confirms that environmental change preceded the CIE on a global scale. Organic dinoflagellate cyst assemblages suggest a local decrease in the amount of river run off reaching the core site during the PETM, possibly in concert with eustatic rise. Moreover, the assemblages suggest changes in seasonality of the regional hydrological system and storm activity. Finally, significant variation in dinoflagellate cyst assemblages during the PETM indicates that southwest Pacific climates varied significantly over time scales of 10³ – 10⁴ years during this event, a finding comparable to similar studies of PETM successions from the New Jersey Shelf.

Remedial Action Plan and final design for stabilization of the inactive uranium mill tailings at Green River, Utah

International Nuclear Information System (INIS)

Matthews, M.L.; Alkema, K.

1991-03-01

This Remedial Action Plan (RAP) has been developed to serve a threefold purpose. It presents the series of activities that are proposed by the US Department of Energy (DOE) to accomplish long-term stabilization and control of radioactive materials at the inactive uranium processing site located near Green River, Utah. It provides a characterization of the present conditions of the site. It also serves to document the concurrence of the state of Utah and the US Nuclear Regulatory Commission (NRC) in the remedial action. This agreement, upon execution by the DOE and the state of Utah, and concurrence by the NRC, becomes Appendix 8 of the Cooperative Agreement

Emplacement and geochemical evolution of eocene plutonic rocks in the Colville batholith

International Nuclear Information System (INIS)

Holder, R.W.

1986-01-01

Eocene plutonic rocks in the Colville batholith are divided on the basis of field evidence and chemical composition into, in order of decreasing age, (1) several calc-alkalic biotite-hornblende monzodiorite to granodiorite intrusions referred to as the Devils Elbow suite, and (2) compositionally variable calc-alkalic to alkali-calcic intrusions referred to as the Herron Creek suite. These Eocene suites are distinct from older, more voluminous, leucocratic granite and granodiorite intrusions, designated the Keller Butte suite, which are calcic and characteristically lack hornblende. Results of qualitative and computer modeling of major element variation and quantitative models of trace element variation in the chemically coherent Bridge Creek intrusions, a member of the Herron Creek suite, are compatible with fractionation of plagioclase feldspar + hornblende + biotite + magnetite + apatite from a parent magma of andesitic composition to account for the observed variation. Strongly curved variation trends preclude mixing as the primary mechanism for the observed variation. It is suggested that parallel variation trends in the other Eocene intrusions are also the result of crystal fractionation. Lateral chemical variations including a decrease in silica saturation suggest the chemical characteristics of these rocks reflect those of parental magmas derived from the mantle, with an unknown amount of crustal contribution. Rotated and angular xenoliths, discordant contacts, and temporal and spatial proximity to graben structures indicate that the Eocene plutons were passively implaced into the upper crust along graben-bounding faults during graben formation, the earlier stages of which appear to have been contemporaneous with regional mylonitic deformation

Provenance evolution in the northern South China Sea and its implication of paleo-drainage systems from Eocene to Miocene

Science.gov (United States)

Cui, Y.; Shao, L.; Qiao, P.

2017-12-01

Geochemistry analysis and detrital zircon U-Pb geochronology aim to fully investigate the "source to sink" patterns of northern South China Sea (SCS) from Eocene to Miocene. Evolutional history of the surrounding drainage system has been highly focused on, in comparison to sedimentary characteristics of the SCS basins. Rapid local provenances were prevailed while large-scale fluvial transport remained to evolve during Eocene. Since early Oligocene, sediments from the South China were more abundantly delivered to the northeastern Pearl River Mouth Basin in addition to Dongsha volcanism supplement. Aside from intrabasinal provenances, long-distance transport started to play significant role in Zhu1 Depression, possibly reaching western and southern Baiyun Sag, partially. Western Qiongdongnan Basin might accept sediments from central Vietnam with its eastern area more affected from Hainan Island and Southern Uplift. In the late Oligocene, due to drastic sea-level changes and rapid exhumation, mafic to altramafic sediments were transported in abundance to Central Depression from Kontum Massif, while multiple provenances casted integrated influence on eastern sedimentary sequences. Southern Baiyun Sag was also affected by an increased supplement from the west Shenhu Uplift or even central Vietnam. Overall pattern did not change greatly since early Miocene, but long-distance transport has become dominant in the northern SCS. Under controlled by regional tectonic cycles, Pearl River gradually evolved into the present scale and exerted its influence on basinal provenances by several stages. Zhu1 Depression was partially delivered sediments from its tributaries in early Oligocene while northern Zhu2 Depression has not been provided abundant materials until late Oligocene. Meanwhile, although detailed transportation routine remains uncertain and controversial, an impressive paleo-channel spanning the whole Qiongdongnan Basin was presumed to supply huge amount of mafic to

Monophyly and extensive extinction of advanced eusocial bees: Insights from an unexpected Eocene diversity

OpenAIRE

Engel, Michael S.

2001-01-01

Advanced eusociality sometimes is given credit for the ecological success of termites, ants, some wasps, and some bees. Comprehensive study of bees fossilized in Baltic amber has revealed an unsuspected middle Eocene (ca. 45 million years ago) diversity of eusocial bee lineages. Advanced eusociality arose once in the bees with significant post-Eocene losses in diversity, leaving today only two advanced eusocial tribes comprising less than 2% of the total bee divers...

Aerial gamma ray and magnetic survey: Powder River R and D Project, Arminto Detail, Wyoming. Final report

International Nuclear Information System (INIS)

1979-05-01

The small detail area, 18 miles by 18 miles, lying near the center of the Powder River Basin, is covered entirely by sediments of the Eocene Wasatch Formation. Historically economic uranium deposits have been worked in the southeast corner of the area which includes the northern extremity of the Pumpkin Buttes district. 127 statistical uranium anomalies were generated for the study area, based on area wide statistics

Eocene and miocene rocks off the northeastern coast of the United States

Science.gov (United States)

Gibson, T.G.

1965-01-01

A grab sample from a depth of 1675 m at a point south of Cape Cod contains early Eocene planktonic Foraminifera and is correlated with the Globorotalia rex zone of Trinidad. The assemblage indicates a depth comparable to that existing today. Regional relations suggest that the Cretaceous and Eocene deposits deepen to the west toward New Jersey. Two mollusk-bearing blocks dredged from the northern side of Georges Bank are correlative with the Miocene Yorktown Formation. Rocks from two other stations are probably Miocene. Benthonic Foraminifera in one sample indicate deposition in cool temperate waters of less than 60 m depth. ?? 1965.

MECO Warming Changes Continental Rainfall Patterns in Eocene Western North America

Science.gov (United States)

Methner, K.; Mulch, A.; Fiebig, J.; Wacker, U.; Gerdes, A.; Graham, S. A.; Chamberlain, C. P.

2016-12-01

Eocene hyperthermals represent temperature extremes superimposed on an existing warm climate. They dramatically affected the marine and terrestrial biosphere, but still remain among the most enigmatic phenomena of Cenozoic climate dynamics. To evaluate the impacts of global warm periods on terrestrial temperature and rainfall records in continental interiors, we sampled a suite of middle Eocene ( 40 Ma) paleosols from a high-elevation mammal fossil locality in the hinterland of the North American Cordillera (Sage Creek Basin, Montana, USA) and integrated laser ablation U-Pb dating of pedogenic carbonate, stable isotope (δ18O) and clumped isotope temperature (Δ47) records. Δ47 temperature data of soil carbonates progressively increase from 23 °C ±3 °C to peak temperatures of 32 °C ±3 °C and subsequently drop to 21 °C ±2 °C and delineate a rapid +9/-11 °C temperature excursion in the paleosol record. This hyperthermal event is accompanied by large and rapid shifts towards low δ18O values and reduced pedogenic CaCO3 contents. U-Pb geochronology of the paleosol carbonate confirms a middle Eocene age for soil carbonate formation (39.5 ±1.4 Ma and 40.1 ±0.8 Ma). Based on U-Pb geochronology, magneto- and biostratigraphy we suggest that the recorded Δ47 temperature excursion reflects peak warming during the Middle Eocene Climatic Optimum (MECO). The MECO in continental western North America appears to be characterized by warmer and wetter (sub-humid) conditions in this high-elevation site. Shifts in δ18O values of precipitation and pedogenic CaCO3 contents parallel temperature changes and require modification of mid-latitude rainfall patterns, indicating a profound impact of the MECO on the hydrological cycle and consequently on atmospheric circulation patterns in the hinterland of the North American Cordillera.

Continental temperatures through the early Eocene in western central Europe

Science.gov (United States)

Inglis, G. N.; Collinson, M. E.; Riegel, W.; Wilde, V.; Farnsworth, A.; Lunt, D. J.; Robson, B.; Scott, A. C.; Lenz, O.; Pancost, R.

2016-12-01

In contrast to the marine realm, our understanding of terrestrial temperature change during greenhouse climates is poorly constrained. Recently, branched glycerol dialkyl glycerol tetraethers (brGDGTs) have been used to successfully reconstruct mean annual air temperature (MAAT) during the early Paleogene. However, despite the potential to provide new insights into terrestrial climate, the application of this proxy in lignite and coal deposits is still limited. Using samples recovered from Schöningen, Germany ( 48°N), we provide the first detailed study into the occurrence and distribution of brGDGTs through a sequence of Early Eocene lignites and associated marine interbeds. Branched GDGTs are abundant and present in every sample. In comparison to modern studies, changes in vegetation type do not appear to significantly impact brGDGT distributions; however, there are subtle differences in these distributions between lignites and siliciclastic nearshore marine interbed sediments. Using the most recent brGDGT temperature calibration, we generate the first continental temperature record from central-western continental Europe through the Early Eocene. Lignite-derived MAAT estimates range from 23 to 26°C and those derived from the nearshore marine interbeds always exceed 20°C. These estimates are consistent with other mid-latitude palaeoclimate proxy records which indicate enhanced early Eocene warmth. In the basal part of the section, warming is recorded in both the lignites ( 2°C) and nearshore marine interbeds ( 2-3°C). This culminates in a long-term temperature maximum, likely including the Early Eocene Climatic Optimum (EECO). Although this trend is relatively well established in marginal marine sediments within the SW Pacific, it has rarely been shown in other regions or terrestrial settings. Using a suite of new climate model simulations, our warming trend is consistent with a doubling of CO2 (from 560ppmv to 1120ppmv) which broadly agrees with proxy

Framing Violence and Serial Murder in My Friend Dahmer and Green River Killer

Directory of Open Access Journals (Sweden)

Harriet Earle

2017-03-01

Full Text Available The comics form has not remained untouched by true crime’s massive surge in status across popular culture, especially in America. Comics as a form is uniquely positioned to represent violent and graphic narratives in such a way as to maximise reader affect and create a chronicle of crime that is both entertaining and captivating, guiding and being guided by the reader. Two comics have received massive critical acclaim for their portrayals of ‘famous’ American serial killers: Jeffrey Dahmer in Derf’s 'My Friend Dahmer' (2012 and Arthur Shawcross in Jeff Jensen & Jonathan Case’s 'Green River Killer' (2011. This article considers the framing techniques deployed in both comics. I consider how these two comics, distinct in their artistic presentation and their focus, frame their respective subjects and represent the complexities of serial murder. To conclude, I perform a close analysis of one framing aspect of 'My Friend Dahmer' and expand on what the execution of this technique can tell us about comics as a true crime form.

Sensitivity of the Palaeocene-Eocene Thermal Maximum climate to cloud properties.

Science.gov (United States)

Kiehl, Jeffrey T; Shields, Christine A

2013-10-28

The Palaeocene-Eocene Thermal Maximum (PETM) was a significant global warming event in the Earth's history (approx. 55 Ma). The cause for this warming event has been linked to increases in greenhouse gases, specifically carbon dioxide and methane. This rapid warming took place in the presence of the existing Early Eocene warm climate. Given that projected business-as-usual levels of atmospheric carbon dioxide reach concentrations of 800-1100 ppmv by 2100, it is of interest to study past climates where atmospheric carbon dioxide was higher than present. This is especially the case given the difficulty of climate models in simulating past warm climates. This study explores the sensitivity of the simulated pre-PETM and PETM periods to change in cloud condensation nuclei (CCN) and microphysical properties of liquid water clouds. Assuming lower levels of CCN for both of these periods leads to significant warming, especially at high latitudes. The study indicates that past differences in cloud properties may be an important factor in accurately simulating past warm climates. Importantly, additional shortwave warming from such a mechanism would imply lower required atmospheric CO2 concentrations for simulated surface temperatures to be in reasonable agreement with proxy data for the Eocene.

Evaluating effectiveness and constraints of private sector agricultural extension services of the Green River Project in Imo and Rivers States, Nigeria

Directory of Open Access Journals (Sweden)

Onyinyechi I. Ogbonna

2016-08-01

Full Text Available Background: Oil exploration operations decreased the cultivable lands of rural people in the study area, leading to the establishment of the Green River Project (GRP. This study assessed the effectiveness and constraints of private sector extension services of GRP in Imo and Rivers States, Nigeria. Objectives: To analyse the roles and effectiveness of, as well as constraints to, the GRP in the area. Method: A multistage sampling technique was used to select 120 respondents. Descriptive statistics, factor analysis, chi square and t-test were used to analyse the data. Results: Roles of GRP in farming technologies dissemination included training of farmers on fish pond construction technique and maintenance of good pH levels. There was significant improvement in standard of living (X2 = 15.7; p ≤ 0.05 and size of production (t = 6.398; p ≤ 0.05 of the respondents after participation. In terms of the effectiveness of private sector deliveries on public policies, the programme had effect on beneficiaries’ access to credit, education of wards and poverty reduction. But it is worthy to note that the observed changes may not have been solely caused by the GRP, given that there could be many other factors affecting fish farming, either positively or negatively. Serious implementation constraints to effective performance of GRP included organisational, input and sustainability constraints. Conclusion: It was recommended that there should be timely provision of sufficient inputs to farmers and measures to improve organisation of private sector extension services in the area in order to enhance development.

Foraminiferal and carbon isotope stratigraphy through the Paleocene-Eocene transition at Dee Stream, Marlborough, New Zealand

International Nuclear Information System (INIS)

Hancock, H.J.L.; Dickens, G.R.; Strong, C.P.; Hollis, C.J.; Field, B.D.

2003-01-01

Dee Stream in the Clarence River valley of New Zealand bisects a well-exposed section of marine sedimentary rocks deposited in the Early Paleogene at high southern latitudes. One hundred metres of strata lying within this section and comprising cm-dm well-bedded, siliceous limestone with marly partings was mapped, logged, and sampled to establish a detailed foraminiferal and carbon isotope stratigraphy and to examine environmental changes across the Paleocene-Eocene thermal maximum (PETM). Although low abundance and poor preservation of planktic and benthic foraminifera characterises much of the Paleocene, foraminifera and carbon isotopes clearly show that the section spans the Upper Paleocene to Lower Eocene planktic foraminiferal zones from Zone P4 to Subzone P6b, and the Subbotina triloculinoides to Pseudohastigerina wilcoxensis Zones. The δ 13 C record correlates closely to other δ 13 C curves generated from other key Early Paleogene carbonate sequences. The Dee Stream logged section contains a 1 m thick PETM interval at 26.5 m at the base of Zone P5, or the Morozovella velascoensis Subzone. Here, benthic foraminifera undergo significant extinction, Morozovella aequa makes its first appearance, and the δ 13 C of carbonate decreases by 2 permille. The benthic foraminifer Bulimina tuxpamensis dominates benthic assemblages immediately following the onset of the PETM interval, suggesting dysoxic bottom waters during this event. In conjunction with other recently examined sections from the Marlborough region, the thick and apparently continuous Paleogene record at Dee Stream provides an important site for understanding environmental change on high-latitude continental margins during the Paleogene, including the PETM. (author). 54 refs., 10 figs., 2 tabs

Middle Eocene seagrass facies from Apennine carbonate platforms (Italy)

Science.gov (United States)

Tomassetti, Laura; Benedetti, Andrea; Brandano, Marco

2016-04-01

Two stratigraphic sections located in the Latium-Abruzzi (Monte Porchio, Central Apennines, Central Italy) and in the Apulian carbonate platform (S. Cesarea-Torre Tiggiano, Salento, Southern Italy) were measured and sampled to document the sedimentological characteristic and the faunistic assemblages of Middle Eocene seagrass deposits. The faunistic assemblages are dominated by porcellaneous foraminifera Orbitolites, Alveolina, Idalina, Spiroloculina, Quinqueloculina, Triloculina and abundant hooked-shaped gypsinids, associated with hooked red algae and green algae Halimeda. Fabiania, rotaliids and textulariids as well as nummulitids are subordinated. The samples were assigned to Lutetian (SBZ13-16) according to the occurrence of Nummulites cf. lehneri, Alveolina ex. gr. elliptica, Idalina berthelini, Orbitolites complanatus, Slovenites decastroi and Medocia blayensis. At Santa Cesarea reticulate nummulites occur in association with Alveolina spp. and Halkyardia minima marking the lower Bartonian (SBZ17). Three main facies associations have been recognised: I) larger porcellaneous foraminiferal grainstones with orbitolitids and alveolinids deposited into high-energy shallow-water settings influenced by wave processes that reworked the sediments associated with a seagrass; II) grainstone to packstone with small porcellaneous foraminifera and abundant permanently-attached gypsinids deposited in a more protected (e.g., small embayment) in situ vegetated environment; III) bioclastic packstone with parautochthonous material reworked from the seagrass by rip currents and accumulated into rip channels in a slightly deeper environment. The biotic assemblages suggest that the depositional environment is consistent with tropical to subtropical vegetated environments within oligotrophic conditions.

Eocene Loranthaceae pollen pushes back divergence ages for major splits in the family.

Science.gov (United States)

Grímsson, Friðgeir; Kapli, Paschalia; Hofmann, Christa-Charlotte; Zetter, Reinhard; Grimm, Guido W

2017-01-01

We revisit the palaeopalynological record of Loranthaceae, using pollen ornamentation to discriminate lineages and to test molecular dating estimates for the diversification of major lineages. Fossil Loranthaceae pollen from the Eocene and Oligocene are analysed and documented using scanning-electron microscopy. These fossils were associated with molecular-defined clades and used as minimum age constraints for Bayesian node dating using different topological scenarios. The fossil Loranthaceae pollen document the presence of at least one extant root-parasitic lineage (Nuytsieae) and two currently aerial parasitic lineages (Psittacanthinae and Loranthinae) by the end of the Eocene in the Northern Hemisphere. Phases of increased lineage diversification (late Eocene, middle Miocene) coincide with global warm phases. With the generation of molecular data becoming easier and less expensive every day, neontological research should re-focus on conserved morphologies that can be traced through the fossil record. The pollen, representing the male gametophytic generation of plants and often a taxonomic indicator, can be such a tracer. Analogously, palaeontological research should put more effort into diagnosing Cenozoic fossils with the aim of including them into modern systematic frameworks.

Tarsal morphology of the pleuraspidotheriid mammal Hilalia from the middle Eocene of Turkey

Directory of Open Access Journals (Sweden)

Gregoire Metais

2017-03-01

Full Text Available Pleuraspidotheriids are a group of primitive ungulate mammals that, until recently, were thought to be restricted to the late Paleocene of Western Europe. It has been hypothesized that this family actually survived in Central Anatolia until at least the middle Eocene. However, these anachronistically young Anatolian “survivors”, including the genus Hilalia, were previously documented mainly by dental remains. Here, we describe the previously unknown astragalus of Hilalia saribeya, which confirms the pleuraspidotheriid affinities of the genus, and supports phylogenetic reconstructions that place Hilalia as the sister group of Pleuraspidotherium. The morphology of the astragalus suggests sub-cursorial plantigrade locomotion for H. saribeya, although its tarsal morphology remains generalized enough that scansorial capabilities cannot be ruled out. The evolution of Hilalia is addressed in the context of the apparent geographic isolation of Central Anatolia during the Eocene. The endemic character of the mammalian fauna of Central Anatolia during the middle Eocene emphasizes how the complex paleogeography of the northern margin of Neotethys impacted local biotas in a region situated at the crossroads of very distinctive biogeographic zones.

A new sawshark, Pristiophorus laevis, from the Eocene of Antarctica with comments on Pristiophorus lanceolatus.

Science.gov (United States)

Engelbrecht, Andrea; Mörs, Thomas; Reguero, Marcelo A; Kriwet, Jürgen

2017-01-01

The highly fossiliferous Eocene deposits of the Antarctic Peninsula are among the most productive sites for fossil remains in the Southern Hemisphere and offer rare insights into high-latitude faunas during the Palaeogene. Chondrichthyans, which are represented by abundant isolated remains, seemingly dominate the marine assemblages. Eocene Antarctic sawsharks have only been known from few isolated rostral spines up to now, that were assigned to Pristiophorus lanceolatus . Here, we present the first oral teeth of a sawshark from the Eocene of Seymour Island and a re-evaluation of previously described Pristiophorus remains from Gondwana consisting exclusively of rostral spines. The holotype of Pristiophorus lanceolatus represents a single, abraded and insufficiently illustrated spine from the Oligocene of New Zealand. All other Cenozoic rostral spines assigned to this species are morphologically very indistinct and closely resemble those of living taxa. Consequently, we regard this species as dubious and introduce a new species, Pristiophorus laevis , based on oral teeth. The combination of dental characteristics of the new species makes it unique compared to all other described species based on oral teeth. Rostral spines from the Eocene of Seymour Island are assigned to this new species whereas those from other Cenozoic Gondwana localities remain ambiguous.

Porosity and sonic velocity depth trends of Eocene chalk in Atlantic Ocean: Influence of effective stress and temperature

DEFF Research Database (Denmark)

Awedalkarim, Ahmed; Fabricius, Ida Lykke

2014-01-01

We aimed to relate changes in porosity and sonic velocity data, measured on water-saturated Eocene chalks from 36 Ocean Drilling Program drill sites in the Atlantic Ocean, to vertical effective stress and thermal maturity. We considered only chalk of Eocene age to avoid possible influence...... not show or at least it is difficult to define a clear pore-stiffening contact cementation trend as the Ontong Java Plateau chalk. Mechanical compaction is the principal cause of porosity reduction (at shallow depths) in the studied Eocene chalk, at least down to about 5MPa Terzaghi׳s effective stress...

Eocene greenhouse climate revealed by coupled clumped isotope-Mg/Ca thermometry.

Science.gov (United States)

Evans, David; Sagoo, Navjit; Renema, Willem; Cotton, Laura J; Müller, Wolfgang; Todd, Jonathan A; Saraswati, Pratul Kumar; Stassen, Peter; Ziegler, Martin; Pearson, Paul N; Valdes, Paul J; Affek, Hagit P

2018-02-06

Past greenhouse periods with elevated atmospheric CO 2 were characterized by globally warmer sea-surface temperatures (SST). However, the extent to which the high latitudes warmed to a greater degree than the tropics (polar amplification) remains poorly constrained, in particular because there are only a few temperature reconstructions from the tropics. Consequently, the relationship between increased CO 2 , the degree of tropical warming, and the resulting latitudinal SST gradient is not well known. Here, we present coupled clumped isotope (Δ 47 )-Mg/Ca measurements of foraminifera from a set of globally distributed sites in the tropics and midlatitudes. Δ 47 is insensitive to seawater chemistry and therefore provides a robust constraint on tropical SST. Crucially, coupling these data with Mg/Ca measurements allows the precise reconstruction of Mg/Ca sw throughout the Eocene, enabling the reinterpretation of all planktonic foraminifera Mg/Ca data. The combined dataset constrains the range in Eocene tropical SST to 30-36 °C (from sites in all basins). We compare these accurate tropical SST to deep-ocean temperatures, serving as a minimum constraint on high-latitude SST. This results in a robust conservative reconstruction of the early Eocene latitudinal gradient, which was reduced by at least 32 ± 10% compared with present day, demonstrating greater polar amplification than captured by most climate models.

Vegetation greenness modelling in response to interannual precipitation and temperature changes between 2001 and 2012 in Liao River Basin in Jilin Province, China.

Science.gov (United States)

Lin, Xiao-Sheng; Tang, Jie; Li, Zhao-Yang; Li, Hai-Yi

2016-01-01

Liao River basin in Jilin Province is the place of origin of the Dongliao River. This study gives a comprehensive analysis of the vegetation coverage in the region and provides a potential theoretical basis for ecological restoration. The seasonal variation of vegetation greenness and dynamics based on the Normalized Difference Vegetation Index (NDVI) in major land cover types in the region was studied. Analyzing the relationship NDVI, temperature and rainfall, we derived a set of predictor variables from 2001 to 2012 using the MODIS Terra level 1 Product (MOD02QKM). The results showed a general increasing trend in NDVI value in the region, while 34.63 % of the region showed degradation. NDVI values begin to rise from April when plants are regreening and they drop in September when temperature are decreasing and the leaves are falling in the study area and temperature was found decreasing during the period of 2001-2012 while rainfall showed an increasing trend. This model could be used to observe the change in vegetation greenness and the dynamic effects of temperature and rainfall. This study provided important data for the environmental protection of the basin area. And we hope to provide scientific analysis for controlling water and soil erosion, maintaining the sustainable productivity of land resources, enhancing the treatment of water pollution and stimulating the virtuous cycle of the ecological system.

Identification of the Paleocene-Eocene boundary in coastal strata in the Otway Basin, Victoria, Australia

Science.gov (United States)

Frieling, Joost; Huurdeman, Emiel P.; Rem, Charlotte C. M.; Donders, Timme H.; Pross, Jörg; Bohaty, Steven M.; Holdgate, Guy R.; Gallagher, Stephen J.; McGowran, Brian; Bijl, Peter K.

2018-02-01

Detailed, stratigraphically well-constrained environmental reconstructions are available for Paleocene and Eocene strata at a range of sites in the southwest Pacific Ocean (New Zealand and East Tasman Plateau; ETP) and Integrated Ocean Discovery Program (IODP) Site U1356 in the south of the Australo-Antarctic Gulf (AAG). These reconstructions have revealed a large discrepancy between temperature proxy data and climate models in this region, suggesting a crucial error in model, proxy data or both. To resolve the origin of this discrepancy, detailed reconstructions are needed from both sides of the Tasmanian Gateway. Paleocene-Eocene sedimentary archives from the west of the Tasmanian Gateway have unfortunately remained scarce (only IODP Site U1356), and no well-dated successions are available for the northern sector of the AAG. Here we present new stratigraphic data for upper Paleocene and lower Eocene strata from the Otway Basin, southeast Australia, on the (north)west side of the Tasmanian Gateway. We analyzed sediments recovered from exploration drilling (Latrobe-1 drill core) and outcrop sampling (Point Margaret) and performed high-resolution carbon isotope geochemistry of bulk organic matter and dinoflagellate cyst (dinocyst) and pollen biostratigraphy on sediments from the regional lithostratigraphic units, including the Pebble Point Formation, Pember Mudstone and Dilwyn Formation. Pollen and dinocyst assemblages are assigned to previously established Australian pollen and dinocyst zonations and tied to available zonations for the SW Pacific. Based on our dinocyst stratigraphy and previously published planktic foraminifer biostratigraphy, the Pebble Point Formation at Point Margaret is dated to the latest Paleocene. The globally synchronous negative carbon isotope excursion that marks the Paleocene-Eocene boundary is identified within the top part of the Pember Mudstone in the Latrobe-1 borehole and at Point Margaret. However, the high abundances of the

Tracing the Eocene-Oligocene transition: A case study from North Bohemia

Czech Academy of Sciences Publication Activity Database

Kvaček, Z.; Teodoridis, V.; Mach, K.; Přikryl, Tomáš; Dvořák, Z.

2014-01-01

Roč. 89, č. 1 (2014), s. 21-66 ISSN 1214-1119 Keywords : boundary * climate * Early Oligocene * fauna * flora * Late Eocene * vegetation Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.515, year: 2014

Paleogene Vertebrate Paleontology, Geology and Remote Sensing in the Wind River Basin

Science.gov (United States)

Stucky, R. K.; Krishtalka, L.

1985-01-01

Biostratigraphic and lithostratigraphic studies were used to correlate different events in the geologic evolution of the northeastern part of the Wind River Basin and have suggested several conclusions. Laterally equivalent exposures of the Lysite member from Cedar Ridge to Bridger Creek show a gradation in lithology from interbedded boulder conglomerates and sandstones to interbedded lenticular sandstones and mudstones to interbedded carbonaceous shales, coals and tabular sandstones. This gradation suggests a shift from alluvial fan to braided stream to paludal or lacustrine sedimentary environments during the late early Eocene. The Lysite and Lost Cabin members of the Wind River Formation are in fault contact in the Bridger Creek area and may intertongue to the east along Cedar Ridge. Ways in which remote sensing could be used in these studies are discussed.

Integrated stratigraphy and astronomical tuning of Smirra cores, lower Eocene, Umbria-Marche basin, Italy.

Science.gov (United States)

Lauretano, Vittoria; Turtù, Antonio; Hilgen, Frits; Galeotti, Simone; Catanzariti, Rita; Reichart, Gert Jan; Lourens, Lucas J.

2016-04-01

The early Eocene represents an ideal case study to analyse the impact of increase global warming on the ocean-atmosphere system. During this time interval, the Earth's surface experienced a long-term warming trend that culminated in a period of sustained high temperatures called the Early Eocene Climatic Optimum (EECO). These perturbations of the ocean-atmosphere system involved the global carbon cycle and global temperatures and have been linked to orbital forcing. Unravelling this complex climatic system strictly depends on the availability of high-quality suitable geological records and accurate age models. However, discrepancies between the astrochronological and radioisotopic dating techniques complicate the development of a robust time scale for the early Eocene (49-54 Ma). Here we present the first magneto-, bio-, chemo- and cyclostratigraphic results of the drilling of the land-based Smirra section, in the Umbria Marche Basin. The sediments recovered at Smirra provide a remarkably well-preserved and undisturbed succession of the early Palaeogene pelagic stratigraphy. Bulk stable carbon isotope and X-Ray Fluorescence (XRF) scanning records are employed in the construction of an astronomically tuned age model for the time interval between ~49 and ~54 Ma based on the tuning to long-eccentricity. These results are then compared to the astronomical tuning of the benthic carbon isotope record of ODP Site 1263 to evaluate the different age model options and improve the time scale of the early Eocene by assessing the precise number of eccentricity-related cycles comprised in this critical interval.

A diverse snake fauna from the early Eocene of Vastan Lignite Mine, Gujarat, India

Energy Technology Data Exchange (ETDEWEB)

Rage, J.C.; Folie, A.; Rana, R.S.; Singh, H.; Rose, K.D.; Smith, T. [Museum National Historical Nature, Paris (France)

2008-09-15

The early Eocene (Ypresian) Cambay Formation of Vastan Lignite Mine in Gujarat, western India, has produced a diverse assemblage of snakes including at least ten species that belong to the Madtsoiidae, Palaeophiidae (Palaeophis and Pterosphenus), Boidae, and several Caenophidia. Within the latter taxon, the Colubroidea are represented by Russellophis crassus sp. nov. (Russellophiidae) and by Procerophis sahnii gen. et sp. nov. Thaumastophis missiaeni gen. et sp. nov. is a caenophidian of uncertain family assignment. At least two other forms probably represent new genera and species, but they are not named; both appear to be related to the Caenophidia. The number of taxa that represent the Colubroidea or at least the Caenophidia, i.e., advanced snakes, is astonishing for the Eocene. This is consistent with the view that Asia played an important part in the early history of these taxa. The fossils come from marine and continental levels; however, no significant difference is evident between faunas from these levels. The fauna from Vastan Mine includes highly aquatic, amphibious, and terrestrial snakes. All are found in the continental levels, including the aquatic palaeophiids, whereas the marine beds yielded only two taxa. Vastan Mine is only the second locality in which the palaeophiids Palaeophis and Pterosphenus co-occur. The composition of the fauna from Vastan is on the whole similar to that of the early Eocene of Europe; however, comparisons with early Eocene faunas of other continents are not possible because they are poorly known or unknown.

Customer value in green power purchases

International Nuclear Information System (INIS)

Welsh, L.

1998-01-01

A discussion about generating electricity from renewable energy sources was presented. The Environment Canada/ENMAX green power contract stipulates that in order for electricity to quality as green power it must be generated by renewable energy sources such as wind, solar, combustion of sustainably produced biomass, or run-of-the-river hydroelectricity. The contract also includes emissions reduction credit (ERC) ownership for greenhouse gases, sulphur dioxide, nitrogen oxides, particulates, and toxics. By using green power in some of its own facilities the government demonstrates its support for renewable energy sources, and provides the initial market for the industry to build up its capacity to service larger markets. The emission reduction credits 'earned' could be added to the government inventories as environmental assets

Before the freeze: otoliths from the Eocene of Seymour Island, Antarctica, reveal dominance of gadiform fishes (Teleostei).

Science.gov (United States)

Schwarzhans, Werner; Mörs, Thomas; Engelbrecht, Andrea; Reguero, Marcelo; Kriwet, Jürgen

2017-01-01

The first record of fossil teleostean otoliths from Antarctica is reported. The fossils were obtained from late Early Eocene shell beds of the La Meseta Formation, Seymour Island that represent the last temperate marine climate phase in Antarctica prior to the onset of cooling and subsequent glaciation during the late Eocene. A total of 17 otolith-based teleost taxa are recognized, with 10 being identifiable to species level containing nine new species and one new genus: Argentina antarctica sp. nov., Diaphus? marambionis sp. nov., Macruronus eastmani sp. nov., Coelorinchus balushkini sp. nov., Coelorinchus nordenskjoeldi sp. nov., Palimphemus seymourensis sp. nov., Hoplobrotula? antipoda sp. nov., Notoberyx cionei gen. et sp. nov. and Cepola anderssoni sp. nov. Macruronus eastmani sp. nov. is also known from the late Eocene of Southern Australia, and Tripterophycis immutatus Schwarzhans, widespread in the southern oceans during the Eocene, has been recorded from New Zealand, southern Australia, and now Antarctica. The otolith assemblage shows a typical composition of temperate fishes dominated by gadiforms, very similar at genus and family levels to associations known from middle Eocene strata of New Zealand and the late Eocene of southern Australia, but also to the temperate Northern Hemisphere associations from the Paleocene of Denmark. The Seymour Island fauna bridges a gap in the record of global temperate marine teleost faunas during the early Eocene climate maximum. The dominant gadiforms are interpreted as the main temperate faunal component, as in the Paleocene of Denmark. Here they are represented by the families Moridae, Merlucciidae (Macruroninae), Macrouridae and Gadidae. Nowadays Gadidae are a chiefly Northern Hemisphere temperate family. Moridae, Macruroninae and Macrouridae live today on the lower shelf to deep-water or mesopelagically with Macruroninae being restricted to the Southern Ocean. The extant endemic Antarctic gadiform family

Early Eocene rodents (Mammalia) from the Subathu Formation of ...

Indian Academy of Sciences (India)

1997a, b). Most of the rodents from this stratigraphic level have been referred to a rather diverse family Cha- pattimyidae ... Herein we describe a new early Eocene rodent assemblage .... thick zone of brownish red shales that occur as a ..... 1997b;. Plate 3, figure 31). ...... northwestern Pakistan and remarks on the collision.

Characterization of middle Eocene tide-influenced delta: a study ...

Indian Academy of Sciences (India)

42

Running Title: Eocene tide-influenced delta in South Cambay Basin. Manuscript. Click here to view linked References. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10 .... systematic documentation of the facies types to establish the depositional environment of the .... Hazad Member consists of a number of sandstone units separated by intervening ...

Reserves in western basins: Part 1, Greater Green River basin

Energy Technology Data Exchange (ETDEWEB)

1993-10-01

This study characterizes an extremely large gas resource located in low permeability, overpressured sandstone reservoirs located below 8,000 feet drill depth in the Greater Green River basin, Wyoming. Total in place resource is estimated at 1,968 Tcf. Via application of geologic, engineering and economic criteria, the portion of this resource potentially recoverable as reserves is estimated. Those volumes estimated include probable, possible and potential categories and total 33 Tcf as a mean estimate of recoverable gas for all plays considered in the basin. Five plays (formations) were included in this study and each was separately analyzed in terms of its overpressured, tight gas resource, established productive characteristics and future reserves potential based on a constant $2/Mcf wellhead gas price scenario. A scheme has been developed to break the overall resource estimate down into components that can be considered as differing technical and economic challenges that must be overcome in order to exploit such resources: in other words, to convert those resources to economically recoverable reserves. Total recoverable reserves estimates of 33 Tcf do not include the existing production from overpressured tight reservoirs in the basin. These have estimated ultimate recovery of approximately 1.6 Tcf, or a per well average recovery of 2.3 Bcf. Due to the fact that considerable pay thicknesses can be present, wells can be economic despite limited drainage areas. It is typical for significant bypassed gas to be present at inter-well locations because drainage areas are commonly less than regulatory well spacing requirements.

Crown Group Lejeuneaceae and Pleurocarpous Mosses in Early Eocene (Ypresian Indian Amber.

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Jochen Heinrichs

Full Text Available Cambay amber originates from the warmest period of the Eocene, which is also well known for the appearance of early angiosperm-dominated megathermal forests. The humid climate of these forests may have triggered the evolution of epiphytic lineages of bryophytes; however, early Eocene fossils of bryophytes are rare. Here, we present evidence for lejeuneoid liverworts and pleurocarpous mosses in Cambay amber. The preserved morphology of the moss fossil is inconclusive for a detailed taxonomic treatment. The liverwort fossil is, however, distinctive; its zig-zagged stems, suberect complicate-bilobed leaves, large leaf lobules, and small, deeply bifid underleaves suggest a member of Lejeuneaceae subtribe Lejeuneinae (Harpalejeunea, Lejeunea, Microlejeunea. We tested alternative classification possibilities by conducting divergence time estimates based on DNA sequence variation of Lejeuneinae using the age of the fossil for corresponding age constraints. Consideration of the fossil as a stem group member of Microlejeunea or Lejeunea resulted in an Eocene to Late Cretaceous age of the Lejeuneinae crown group. This reconstruction is in good accordance with published divergence time estimates generated without the newly presented fossil evidence. Balancing available evidence, we describe the liverwort fossil as the extinct species Microlejeunea nyiahae, representing the oldest crown group fossil of Lejeuneaceae.

Crown Group Lejeuneaceae and Pleurocarpous Mosses in Early Eocene (Ypresian) Indian Amber.

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Heinrichs, Jochen; Scheben, Armin; Bechteler, Julia; Lee, Gaik Ee; Schäfer-Verwimp, Alfons; Hedenäs, Lars; Singh, Hukam; Pócs, Tamás; Nascimbene, Paul C; Peralta, Denilson F; Renner, Matt; Schmidt, Alexander R

2016-01-01

Cambay amber originates from the warmest period of the Eocene, which is also well known for the appearance of early angiosperm-dominated megathermal forests. The humid climate of these forests may have triggered the evolution of epiphytic lineages of bryophytes; however, early Eocene fossils of bryophytes are rare. Here, we present evidence for lejeuneoid liverworts and pleurocarpous mosses in Cambay amber. The preserved morphology of the moss fossil is inconclusive for a detailed taxonomic treatment. The liverwort fossil is, however, distinctive; its zig-zagged stems, suberect complicate-bilobed leaves, large leaf lobules, and small, deeply bifid underleaves suggest a member of Lejeuneaceae subtribe Lejeuneinae (Harpalejeunea, Lejeunea, Microlejeunea). We tested alternative classification possibilities by conducting divergence time estimates based on DNA sequence variation of Lejeuneinae using the age of the fossil for corresponding age constraints. Consideration of the fossil as a stem group member of Microlejeunea or Lejeunea resulted in an Eocene to Late Cretaceous age of the Lejeuneinae crown group. This reconstruction is in good accordance with published divergence time estimates generated without the newly presented fossil evidence. Balancing available evidence, we describe the liverwort fossil as the extinct species Microlejeunea nyiahae, representing the oldest crown group fossil of Lejeuneaceae.

The terrestrial hydro-climate of the Early Eocene: insights from the oxygen and clumped isotope composition of pedogenic siderite

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van Dijk, J.; Fernandez, A.; Müller, I.; White, T. S.; Bernasconi, S. M.

2016-12-01

The Early Eocene (56 Ma) is the youngest period of Earth's history when CO2 concentrations in the atmosphere (600-1500 ppm) reached levels close to those predicted for future emission scenarios. Proxy-based climate reconstructions from this interval can therefore be used to gain insights on effects that anthropogenic emissions might have on the climate system. So far, Early Eocene climatic data is limited to the oceans, where proxies for temperature are abundant and relatively well understood. However, in order to get a complete picture of the Early Eocene climate, temperature and rainfall reconstructions on the continental paleo-surface are needed. Here, we present clumped and stable oxygen isotope measurements of siderite samples collected along a North-South transect in the North American Continent. These siderites formed in kaolinitic soils that developed globally under the extremely wet and warm conditions of the Early Eocene. They provide a record of both soil temperature and the δ18O composition of meteoric water, which can be used to unravel the regional paleo-precipitation rate. Both parameters were estimated using an elaborate in-house calibration constructed with synthetic siderite precipitated in the presence or absence of iron reducing bacteria. Measurements of δD on plant-derived N-alkanes present within the same soils align well with our δ18Owater data, confirming an Early Eocene meteoric water line similar to the present day. We provide an estimate of the meridional temperature gradient during the Early Eocene and offer constraints on the boundary conditions of the Earth's hydrologic cycle under high pCO2.

Eocene volcanism and the origin of horizon A

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Gibson, T.G.; Towe, K.M.

1971-01-01

A series of closely time-equivalent deposits that correlate with seismic reflector horizon A exists along the coast of eastern North America. These sediments of Late-Early to Early-Middle Eocene age contain an authigenic mineral suite indicative of the alteration of volcanic glass. A volcanic origin for these siliceous deposits onshore is consistent with a volcanic origin for the cherts of horizon A offshore.

Sea Surface Warming and Increased Aridity at Mid-latitudes during Eocene Thermal Maximum 2

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Harper, D. T.; Zeebe, R. E.; Hoenisch, B.; Schrader, C.; Lourens, L. J.; Zachos, J. C.

2017-12-01

Early Eocene hyperthermals, i.e. abrupt global warming events characterized by the release of isotopically light carbon to the atmosphere, can provide insight into the sensitivity of the Earth's climate system and hydrologic cycle to carbon emissions. Indeed, the largest Eocene hyperthermal, the Paleocene-Eocene Thermal Maximum (PETM), has provided one case study of extreme and abrupt global warming, with a mass of carbon release roughly equivalent to total modern fossil fuel reserves and a release rate 1/10 that of modern. Global sea surface temperatures (SST) increased by 5-8°C during the PETM and extensive evidence from marine and terrestrial records indicates significant shifts in the hydrologic cycle consistent with an increase in poleward moisture transport in response to surface warming. The second largest Eocene hyperthermal, Eocene Thermal Maximum 2 (ETM-2) provides an additional calibration point for determining the sensitivity of climate and the hydrologic cycle to massive carbon release. Marine carbon isotope excursions (CIE) and warming at the ETM-2 were roughly half as large as at the PETM, but reliable evidence for shifts in temperature and the hydrologic cycle are sparse for the ETM-2. Here, we utilize coupled planktic foraminiferal δ18O and Mg/Ca to determine ΔSST and ΔSSS (changes in sea surface temperature and salinity) for ETM-2 at ODP Sites 1209 (28°N paleolatitude in the Pacific) and 1265 (42°S paleolatitude in the S. Atlantic), accounting for potential pH influence on the two proxies by using LOSCAR climate-carbon cycle simulated ΔpH. Our results indicate a warming of 2-4°C at both mid-latitude sites and an increase in SSS of 1-3ppt, consistent with simulations of early Paleogene hydroclimate that suggest an increase in low- to mid-latitude aridity due to an intensification of moisture transport to high-latitudes. Furthermore, the magnitude of the CIE and warming for ETM-2 scales with the CIE and warming for the PETM, suggesting that

New euprimate postcrania from the early Eocene of Gujarat, India, and the strepsirrhine-haplorhine divergence.

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Dunn, Rachel H; Rose, Kenneth D; Rana, Rajendra S; Kumar, Kishor; Sahni, Ashok; Smith, Thierry

2016-10-01

The oldest primates of modern aspect (euprimates) appear abruptly on the Holarctic continents during a brief episode of global warming known as the Paleocene-Eocene Thermal Maximum, at the beginning of the Eocene (∼56 Ma). When they first appear in the fossil record, they are already divided into two distinct clades, Adapoidea (basal members of Strepsirrhini, which includes extant lemurs, lorises, and bushbabies) and Omomyidae (basal Haplorhini, which comprises living tarsiers, monkeys, and apes). Both groups have recently been discovered in the early Eocene Cambay Shale Formation of Vastan lignite mine, Gujarat, India, where they are known mainly from teeth and jaws. The Vastan fossils are dated at ∼54.5 Myr based on associated dinoflagellates and isotope stratigraphy. Here, we describe new, exquisitely preserved limb bones of these Indian primates that reveal more primitive postcranial characteristics than have been previously documented for either clade, and differences between them are so minor that in many cases we cannot be certain to which group they belong. Nevertheless, the small distinctions observed in some elements foreshadow postcranial traits that distinguish the groups by the middle Eocene, suggesting that the Vastan primates-though slightly younger than the oldest known euprimates-may represent the most primitive known remnants of the divergence between the two great primate clades. Copyright © 2016 Elsevier Ltd. All rights reserved.

Origin of uraniferous phosphate beds in Wilkins Peak member of Green River Formation, Wyoming

International Nuclear Information System (INIS)

Mott, L.V.; Drever, J.I.

1983-01-01

The distribution of uranium and phosphorus was studied in four drill cores from the Wilkins Peak Member of the Green River Formation in Wyoming. Of the studied occurrences of anomalously high uranium concentrations, 13% were associated with localized organic matter, and the remainder were associated with stratiform phosphate-rich beds. The uranium probably substitutes for calcium in apatite in these beds. It is proposed that the apatite forms by replacement of calcite during times of flooding of the normally highly saline lake. The flood waters bring in phosphorus and cause a decrease in both pH and ratio of bicarbonate to phosphate, which favors the replacement. Uranium is incorporated in the apatite as the apatite forms or soon after. No special source, other than weathering of volcanic ash, is required for the phosphorus or the uranium. The uraniferous phosphatic beds do not appear to have any economic potential at the present time. Misleadingly high concentrations of both uranium and phosphorus are observed in outcrop samples as a result of selective leaching of other components

Modifications to the Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Green River, Utah

International Nuclear Information System (INIS)

1991-10-01

This modification to the Green River Final Remedial Action Plan (FRAP) represents the changes made to the document in accordance with a joint agreement between the US Department of Energy (DOE) and the US Nuclear Regulatory Commission (NRC) outlined in a letter dated August 7, 1991. As specified in this letter, methylene chloride will no longer be analyzed in groundwater samples collected from on-site monitor wells. All references to methylene chloride sampling have been deleted from the FRAP, as indicated by the pages in Section 2.0 of this document

Eocene Loranthaceae pollen pushes back divergence ages for major splits in the family

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Friðgeir Grímsson

2017-06-01

Full Text Available Background We revisit the palaeopalynological record of Loranthaceae, using pollen ornamentation to discriminate lineages and to test molecular dating estimates for the diversification of major lineages. Methods Fossil Loranthaceae pollen from the Eocene and Oligocene are analysed and documented using scanning-electron microscopy. These fossils were associated with molecular-defined clades and used as minimum age constraints for Bayesian node dating using different topological scenarios. Results The fossil Loranthaceae pollen document the presence of at least one extant root-parasitic lineage (Nuytsieae and two currently aerial parasitic lineages (Psittacanthinae and Loranthinae by the end of the Eocene in the Northern Hemisphere. Phases of increased lineage diversification (late Eocene, middle Miocene coincide with global warm phases. Discussion With the generation of molecular data becoming easier and less expensive every day, neontological research should re-focus on conserved morphologies that can be traced through the fossil record. The pollen, representing the male gametophytic generation of plants and often a taxonomic indicator, can be such a tracer. Analogously, palaeontological research should put more effort into diagnosing Cenozoic fossils with the aim of including them into modern systematic frameworks.

Skull osteology of the Eocene amphisbaenian Spathorhynchus fossorium (Reptilia, Squamata) suggests convergent evolution and reversals of fossorial adaptations in worm lizards.

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Müller, Johannes; Hipsley, Christy A; Maisano, Jessica A

2016-11-01

The fossorial amphisbaenians, or worm lizards, are characterized by a suite of specialized characters in the skull and postcranium, however fossil evidence suggests that at least some of these shared derived traits evolved convergently. Unfortunately the lack of detailed knowledge of many fossil taxa has rendered a more precise interpretation difficult. Here we describe the cranial anatomy of the oldest-known well-preserved amphisbaenian, Spathorhynchus fossorium, from the Eocene Green River Formation, Wyoming, USA, using high-resolution X-ray computed tomography (HRXCT). This taxon possesses one of the most strongly reinforced crania known among amphisbaenians, with many dermal bones overlapping each other internally. In contrast to modern taxa, S. fossorium has a paired orbitosphenoid, lacks a true compound bone in the mandible, and possesses a fully enclosed orbital rim. The last feature represents a highly derived structure in that the jugal establishes contact with the frontal internally, reinforcing the posterior orbital margin. S. fossorium also possesses a strongly modified Vidian canal with a previously unknown connection to the ventral surface of the parabasisphenoid. Comparison with the closely related fossil taxon Dyticonastis rensbergeri reveals that these derived traits are also shared by the latter species and potentially represent synapopmorphies of an extinct Paleogene clade of amphisbaenians. The presence of a reinforced orbital rim suggests selection against the loss of a functional eye and indicates an ecology potentially different from modern taxa. Given the currently accepted phylogenetic position of Spathorhynchus and Dyticonastis, we predict that supposedly 'unique' cranial traits traditionally linked to fossoriality such as a fused orbitosphenoid and the reduction of the eye show a more complex character history than previously assumed, including both parallel evolution and reversals to superficially primitive conditions. © 2016

SWOT Analysis of Urban Greening Maintenance and Management in the Central Pearl River Delta

Institute of Scientific and Technical Information of China (English)

Yanning; ZHENG; Fang; JIANG

2013-01-01

We take Shunde District,Foshan City in Guangdong Province for example,to carry out SWOT analysis of urban greening maintenance and management.The strengths of greening management and maintenance in Shunde District are as follows:(i)The greening area and quality are continuously improved in the downtown of Shunde District;(ii)The management and maintenance work is carried out well;(iii)The management and maintenance level tends to be increasingly perfected.The weaknesses of greening management and maintenance are as follows:(i)The fees for greening management and maintenance are very low;(ii)There is corner as yet untouched in the junction of some town streets;(iii)The greening management and maintenance technicians are unprofessional;(iv)The greening management is not in place;(v)There is management vacancy phenomenon in the management and maintenance of regional green space;(vi)The design and construction phase is flawed.Finally,based on the analysis of strengths and weaknesses of greening,we put forth the recommendations for the development of management and maintenance in urban green space.

Lepidological review on the fish fauna of the Kučlín locality (Upper Eocene, Czech Republic)

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš

2011-01-01

Roč. 67, 3/4 (2011), s. 149-156 ISSN 0036-5343 Institutional research plan: CEZ:AV0Z30130516 Keywords : fossil fish fauna * Osteichthyes * scales * morphology * Paleogene * Upper Eocene * Upper Eocene (Czech Republic) Subject RIV: DB - Geology ; Mineralogy http://www.nm.cz/publikace/archiv-en.php?id=4&rok=67&kcislu=3-4&f_=Show

Unravelling the stratigraphy and sedimentation history of the uppermost Cretaceous to Eocene sediments of the Kuching Zone in West Sarawak (Malaysia), Borneo

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Breitfeld, H. Tim; Hall, Robert; Galin, Thomson; BouDagher-Fadel, Marcelle K.

2018-07-01

The Kuching Zone in West Sarawak consists of two different sedimentary basins, the Kayan and Ketungau Basins. The sedimentary successions in the basins are part of the Kuching Supergroup that extends into Kalimantan. The uppermost Cretaceous (Maastrichtian) to Lower Eocene Kayan Group forms the sedimentary deposits directly above a major unconformity, the Pedawan Unconformity, which marks the cessation of subduction-related magmatism beneath SW Borneo and the Schwaner Mountains, due to termination of the Paleo-Pacific subduction. The successions consist of the Kayan and Penrissen Sandstones and are dominated by fluvial channels, alluvial fans and floodplain deposits with some deltaic to tidally-influenced sections in the Kayan Sandstone. In the late Early or early Middle Eocene, sedimentation in this basin ceased and a new basin, the Ketungau Basin, developed to the east. This change is marked by the Kayan Unconformity. Sedimentation resumed in the Middle Eocene (Lutetian) with the marginal marine, tidal to deltaic Ngili Sandstone and Silantek Formation. Upsequence, the Silantek Formation is dominated by floodplain and subsidiary fluvial deposits. The Bako-Mintu Sandstone, a potential lateral equivalent of the Silantek Formation, is formed of major fluvial channels. The top of the Ketungau Group in West Sarawak is formed by the fluvially-dominated Tutoop Sandstone. This shows a transition of the Ketungau Group in time towards terrestrial/fluvially-dominated deposits. Paleocurrent measurements show river systems were complex, but reveal a dominant southern source. This suggests uplift of southern Borneo initiated in the region of the present-day Schwaner Mountains from the latest Cretaceous onwards. Additional sources were local sources in the West Borneo province, Mesozoic melanges to the east and potentially the Malay Peninsula. The Ketungau Group also includes reworked deposits of the Kayan Group. The sediments of the Kuching Supergroup are predominantly

Monophyly and extensive extinction of advanced eusocial bees: insights from an unexpected Eocene diversity.

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Engel, M S

2001-02-13

Advanced eusociality sometimes is given credit for the ecological success of termites, ants, some wasps, and some bees. Comprehensive study of bees fossilized in Baltic amber has revealed an unsuspected middle Eocene (ca. 45 million years ago) diversity of eusocial bee lineages. Advanced eusociality arose once in the bees with significant post-Eocene losses in diversity, leaving today only two advanced eusocial tribes comprising less than 2% of the total bee diversity, a trend analogous to that of hominid evolution. This pattern of changing diversity contradicts notions concerning the role of eusociality for evolutionary success in insects.

The sponge genus Ephydatia from the high-latitude middle Eocene: environmental and evolutionary significance.

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Pisera, Andrzej; Manconi, Renata; Siver, Peter A; Wolfe, Alexander P

2016-01-01

The freshwater sponge species Ephydatia cf. facunda Weltner, 1895 (Spongillida, Spongillidae) is reported for the first time as a fossil from middle Eocene lake sediments of the Giraffe kimberlite maar in northern Canada. The sponge is represented by birotule gemmuloscleres as well as oxea megascleres. Today, E. facunda inhabits warm-water bodies, so its presence in the Giraffe locality provides evidence of a warm climate at high latitudes during the middle Eocene. The morphological similarity of the birotules to modern conspecific forms suggests protracted morphological stasis, comparable to that reported for other siliceous microfossils from the same locality.

Groundwater well inventory and assessment in the area of the proposed Normally Pressured Lance natural gas development project, Green River Basin, Wyoming, 2012

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Sweat, Michael J.

2013-01-01

During May through September 2012, the U.S. Geological Survey, in cooperation with the Bureau of Land Management, inventoried and assessed existing water wells in southwestern Wyoming for inclusion in a possible groundwater-monitor network. Records were located for 3,282 wells in the upper Green River Basin, which includes the U.S. Geological Survey study area and the proposed Normally Pressured Lance natural gas development project area. Records for 2,713 upper Green River Basin wells were determined to be unique (not duplicated) and to have a Wyoming State Engineers Office permit. Further, 376 of these wells were within the U.S. Geological Survey Normally Pressured Lance study area. Of the 376 wells in the U.S. Geological Survey Normally Pressured Lance study area, 141 well records had sufficient documentation, such as well depth, open interval, geologic log, and depth to water, to meet many, but not always all, established monitor well criteria. Efforts were made to locate each of the 141 wells and to document their current condition. Field crews were able to locate 121 of the wells, and the remaining 20 wells either were not located as described, or had been abandoned and the site reclaimed. Of the 121 wells located, 92 were found to meet established monitor well criteria. Results of the field efforts during May through September 2012, and specific physical characteristics of the 92 wells, are presented in this report.

Evidence for middle Eocene Arctic sea ice from diatoms and ice-rafted debris.

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Stickley, Catherine E; St John, Kristen; Koç, Nalân; Jordan, Richard W; Passchier, Sandra; Pearce, Richard B; Kearns, Lance E

2009-07-16

Oceanic sediments from long cores drilled on the Lomonosov ridge, in the central Arctic, contain ice-rafted debris (IRD) back to the middle Eocene epoch, prompting recent suggestions that ice appeared in the Arctic about 46 million years (Myr) ago. However, because IRD can be transported by icebergs (derived from land-based ice) and also by sea ice, IRD records are restricted to providing a history of general ice-rafting only. It is critical to differentiate sea ice from glacial (land-based) ice as climate feedback mechanisms vary and global impacts differ between these systems: sea ice directly affects ocean-atmosphere exchanges, whereas land-based ice affects sea level and consequently ocean acidity. An earlier report assumed that sea ice was prevalent in the middle Eocene Arctic on the basis of IRD, and although somewhat preliminary supportive evidence exists, these data are neither comprehensive nor quantified. Here we show the presence of middle Eocene Arctic sea ice from an extraordinary abundance of a group of sea-ice-dependent fossil diatoms (Synedropsis spp.). Analysis of quartz grain textural characteristics further supports sea ice as the dominant transporter of IRD at this time. Together with new information on cosmopolitan diatoms and existing IRD records, our data strongly suggest a two-phase establishment of sea ice: initial episodic formation in marginal shelf areas approximately 47.5 Myr ago, followed approximately 0.5 Myr later by the onset of seasonally paced sea-ice formation in offshore areas of the central Arctic. Our data establish a 2-Myr record of sea ice, documenting the transition from a warm, ice-free environment to one dominated by winter sea ice at the start of the middle Eocene climatic cooling phase.

Association analysis between spatiotemporal variation of vegetation greenness and precipitation/temperature in the Yangtze River Basin (China).

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Cui, Lifang; Wang, Lunche; Singh, Ramesh P; Lai, Zhongping; Jiang, Liangliang; Yao, Rui

2018-05-23

The variation in vegetation greenness provides good understanding of the sustainable management and monitoring of land surface ecosystems. The present paper discusses the spatial-temporal changes in vegetation and controlling factors in the Yangtze River Basin (YRB) using Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI) for the period 2001-2013. Theil-Sen Median trend analysis, Pearson correlation coefficients, and residual analysis have been used, which shows decreasing trend of the annual mean NDVI over the whole YRB. Spatially, the regions with significant decreasing trends were mainly located in parts of central YRB, and pronounced increasing trends were observed in parts of the eastern and western YRB. The mean NDVI during spring and summer seasons increased, while it decreased during autumn and winter seasons. The seasonal mean NDVI shows spatial heterogeneity due to the vegetation types. The correlation analysis shows a positive relation between NDVI and temperature over most of the YRB, whereas NDVI and precipitation show a negative correlation. The residual analysis shows an increase in NDVI in parts of eastern and western YRB and the decrease in NDVI in the small part of Yangtze River Delta (YRD) and the mid-western YRB due to human activities. In general, climate factors were the principal drivers of NDVI variation in YRB in recent years.

Climatic conditions governing extensive Azolla bloom during the Middle Eocene

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Dekker, Rolande; Speelman, Eveline N.; Barke, Judith; Konijnendijk, Tiuri; Sinninge Damste, Jaap S.; Reichart, Gert-Jan

2010-05-01

Enormous amounts of intact mega- and microspores from the free floating aquatic fern Azolla were found in sediments recovered during Integrated Ocean Drilling Program expedition 302, indicating that Azolla grew and reproduced in situ in the Eocene Arctic Ocean. In general, the Early/Middle Eocene is characterized by enhanced greenhouse conditions with elevated sea surface temperatures (SSTs) in the Arctic (~10°C), while tropical sea surface temperatures (SSTs) were only a little warmer than today (with a mean annual temperature (MAT) of 32-34 °C) (Pearson et al., 2007). The consequently reduced temperature gradient between the equator and the poles and the presence of freshwater at the North Pole as indicated by the presence of the freshwater fern Azolla (Brinkhuis et al., 2006) provide important boundary conditions for understanding the hydrological cycle and latent heat transport during this interval. Here we reconstruct variations in SST and mean annual air temperature using the TEX86 and MBT temperature proxies for the Azolla interval. Sediments from around the Arctic Basin have been analyzed, including samples from Alaska, the Mackenzie Basin, Greenland (IODP core 913b), and Denmark. Furthermore, a high resolution sea surface temperature record for the Azolla interval has been constructed from sediment samples from the Lomonosov Ridge, showing a cyclic signal. Model experiments have shown that the here confirmed low equator-to-pole temperature gradient modulated the hydrological cycle. Since the growth of Azolla is restricted to low salinity conditions, changes in the hydrological cycle are proposed to coincide with the cyclic occurrence of Azolla throughout the interval. To confirm the overlapping presence of high quantities of Azolla and increased precipitation, changes in the hydrogen cycle are reconstructed by creating a high resolution hydrogen isotope record throughout the interval. By performing compound specific analyses (δD) on terrestrial derived

The Early Eocene equable climate problem: can perturbations of climate model parameters identify possible solutions?

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Sagoo, Navjit; Valdes, Paul; Flecker, Rachel; Gregoire, Lauren J

2013-10-28

Geological data for the Early Eocene (56-47.8 Ma) indicate extensive global warming, with very warm temperatures at both poles. However, despite numerous attempts to simulate this warmth, there are remarkable data-model differences in the prediction of these polar surface temperatures, resulting in the so-called 'equable climate problem'. In this paper, for the first time an ensemble with a perturbed climate-sensitive model parameters approach has been applied to modelling the Early Eocene climate. We performed more than 100 simulations with perturbed physics parameters, and identified two simulations that have an optimal fit with the proxy data. We have simulated the warmth of the Early Eocene at 560 ppmv CO2, which is a much lower CO2 level than many other models. We investigate the changes in atmospheric circulation, cloud properties and ocean circulation that are common to these simulations and how they differ from the remaining simulations in order to understand what mechanisms contribute to the polar warming. The parameter set from one of the optimal Early Eocene simulations also produces a favourable fit for the last glacial maximum boundary climate and outperforms the control parameter set for the present day. Although this does not 'prove' that this model is correct, it is very encouraging that there is a parameter set that creates a climate model able to simulate well very different palaeoclimates and the present-day climate. Interestingly, to achieve the great warmth of the Early Eocene this version of the model does not have a strong future climate change Charney climate sensitivity. It produces a Charney climate sensitivity of 2.7(°)C, whereas the mean value of the 18 models in the IPCC Fourth Assessment Report (AR4) is 3.26(°)C±0.69(°)C. Thus, this value is within the range and below the mean of the models included in the AR4.

Palaeoecological and palaeoclimatological implications of the Eocene Northern Hemisphere Azolla phenomenon

NARCIS (Netherlands)

Barke, J.

2010-01-01

The high abundances and cyclic distribution of remains of the freshwater fern Azolla in early middle Eocene sediments from the Arctic Ocean have previously been related to episodic surface water freshening, which was speculated to be orbitally modulated. Our integrated palynological and

Anthracobunids from the Middle Eocene of India and Pakistan Are Stem Perissodactyls

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Cooper, Lisa Noelle; Seiffert, Erik R.; Clementz, Mark; Madar, Sandra I.; Bajpai, Sunil; Hussain, S. Taseer; Thewissen, J. G. M.

2014-01-01

Anthracobunidae is an Eocene family of large mammals from south Asia that is commonly considered to be part of the radiation that gave rise to elephants (proboscideans) and sea cows (sirenians). We describe a new collection of anthracobunid fossils from Middle Eocene rocks of Indo-Pakistan that more than doubles the number of known anthracobunid fossils and challenges their putative relationships, instead implying that they are stem perissodactyls. Cranial, dental, and postcranial elements allow a revision of species and the recognition of a new anthracobunid genus. Analyses of stable isotopes and long bone geometry together suggest that most anthracobunids fed on land, but spent a considerable amount of time near water. This new evidence expands our understanding of stem perissodactyl diversity and sheds new light on perissodactyl origins. PMID:25295875

A roller-like bird (Coracii) from the Early Eocene of Denmark.

Science.gov (United States)

Bourdon, Estelle; Kristoffersen, Anette V; Bonde, Niels

2016-09-27

The fossil record of crown group birds (Neornithes) prior to the Cretaceous-Paleogene boundary is scarce and fragmentary. Early Cenozoic bird fossils are more abundant, but are typically disarticulated and/or flattened. Here we report the oldest roller (Coracii), Septencoracias morsensis gen. et sp. nov. (Primobucconidae), based on a new specimen from the Early Eocene (about 54 million years ago) Fur Formation of Denmark. The new fossil is a nearly complete, three-dimensionally preserved and articulated skeleton. It lies at the lower end of the size range for extant rollers. Salient diagnostic features of Septencoracias relative to other Coracii include the proportionally larger skull and the small, ovoid and dorsally positioned narial openings. Our discovery adds to the evidence that the Coracii had a widespread northern hemisphere distribution in the Eocene. Septencoracias is the oldest substantial record of the Picocoraciae and provides a reliable calibration point for molecular phylogenetic studies.

Is South Korea’s Green Job Policy Sustainable?

Directory of Open Access Journals (Sweden)

Yeon-Mi Jung

2015-07-01

Full Text Available South Korea’s green job policy was implemented in February 2008 as a part of low-carbon green growth policy, but has been discontinued at the present. The country’s actual energy and environmental consumption has continuously increased, and South Korean society has grown increasingly distant from sustainable development. The study constructs a theoretical framework centering on sustainable development and analyzes the process and contents of South Korea’s green job policy. We suggest four findings: First, in terms of ideology, the nation’s green job policy was based on green growth. Implemented as a strategy typical of developing countries, South Korea’s green growth was pursued as weak ecological modernization, relatively stressing economic growth and excluding citizens’ participation. Second, in terms of governance, the nation’s green job policy was led by the central government, thus nearly completely destroying existing legal and institutional infrastructures related to sustainable development. Third, South Korea’s green job policy was defined on the basis of a growth orientation and concentrated on the Four Major Rivers Restoration Project and the NPP project, both of which betrayed considerable problems from the perspective of sustainable development. Fourth, green jobs were created in traditional environmental protection and pollution reduction and therefore limited.

Evidence for ephemeral middle Eocene to early Oligocene Greenland glacial ice and pan-Arctic sea ice.

Science.gov (United States)

Tripati, Aradhna; Darby, Dennis

2018-03-12

Earth's modern climate is defined by the presence of ice at both poles, but that ice is now disappearing. Therefore understanding the origin and causes of polar ice stability is more critical than ever. Here we provide novel geochemical data that constrain past dynamics of glacial ice on Greenland and Arctic sea ice. Based on accurate source determinations of individual ice-rafted Fe-oxide grains, we find evidence for episodic glaciation of distinct source regions on Greenland as far-ranging as ~68°N and ~80°N synchronous with ice-rafting from circum-Arctic sources, beginning in the middle Eocene. Glacial intervals broadly coincide with reduced CO 2 , with a potential threshold for glacial ice stability near ~500 p.p.m.v. The middle Eocene represents the Cenozoic onset of a dynamic cryosphere, with ice in both hemispheres during transient glacials and substantial regional climate heterogeneity. A more stable cryosphere developed at the Eocene-Oligocene transition, and is now threatened by anthropogenic emissions.

Isotopic evidence of a rapid cooling and continuous sedimentation across the Eocene-Oligocene boundary of Wagapadhar and Waior, Kutch

International Nuclear Information System (INIS)

Sarangi, S.; Sarkar, A.; Bhattacharya, S.K.; Ray, A.K.

1998-01-01

High resolution oxygen isotope analysis of samples from two different Eocene Oligocene Boundary (EOB) sections of Wagapadhar and Waior of Kutch area and their correlation with DSDP sites indicate continuity of sedimentation at these sites. A rapid cooling of ∼ 6 degC across the EOB, synchronous with extinction of Eocene larger benthic foraminifera is also observed. (author)

Triggers and consequences of glacial expansion across the Eocene - Oligocene Transition

NARCIS (Netherlands)

Houben, A.J.P.

2012-01-01

The results described in this thesis provide a rather complex picture of climatic, environmental and biotic changes preceding and arising from the onset of Antarctic glaciation. This period is commonly known as the greenhouse to icehouse transition across the Eocene-Oligocene Transition (EOT, 34-33

Geologic implications of large-scale trends in well-log response, northern Green River Basin, Wyoming

International Nuclear Information System (INIS)

Prensky, S.E.

1986-01-01

Well-log response in lower Tertiary and Upper Cretaceous rocks in the northern Green River basin, Wyoming, is examined. Digitally recorded well-log data for selected wells located throughout the basin were processed by computer and displayed as highly compressed depth-scale plots for examining large-scale geologic trends. Stratigraphic units, formed under similar depositional conditions, are distinguishable by differing patterns on these plots. In particular, a strong lithologic contrast between Tertiary and underlying Upper Cretaceous non-marine clastic rocks is revealed and correlated through the study area. Laboratory analysis combined with gamma-ray spectrometry log data show that potassium feldspars in the arkosic Tertiary sandstones cause the contrast. The nature and extent of overpressuring has been examined. Data shift on shale conductivity and shale acoustic transit-time plots, previously ascribed to changes in pore pressure, correspond to stratigraphic changes and not necessarily with changes in pore pressure as indicated by drilling-mud weights. Gulf Coast well-log techniques for detecting overpressuring are unreliable and ineffectual in this basin, which has experienced significantly different geologic depositional and tectonic conditions

Managing Basin Interdependencies in a Heterogeneous, Highly Utilized and Data Scarce River Basin in Semi-Arid Africa : The case of the Pangani River Basin, Eastern Africa

NARCIS (Netherlands)

Kiptala, J.K.

2016-01-01

For integrated water resources management both blue and green water resources in a river basin and their spatial and temporal distribution have to be considered. This is because green and blue water uses are interdependent. In sub-Saharan Africa, the upper landscapes are often dominated by rainfed

Managing Basin Interdependencies in a Heterogeneous, Highly Utilized and Data Scarce River Basin in Semi-Arid Africa: The Case of the Pangani River Basin, Eastern Africa

NARCIS (Netherlands)

Kiptala, J.K.

2016-01-01

For integrated water resources management both blue and green water resources in a river basin and their spatial and temporal distribution have to be considered. This is because green and blue water uses are interdependent. In sub-Saharan Africa, the upper landscapes are often dominated by rainfed

Tempo and scale of late Paleocene and early Eocene carbon isotope cycles: Implications for the origin of hyperthermals

Science.gov (United States)

Zachos, James C.; McCarren, Heather; Murphy, Brandon; Röhl, Ursula; Westerhold, Thomas

2010-10-01

The upper Paleocene and lower Eocene are marked by several prominent (> 1‰) carbon isotope (δ 13C) excursions (CIE) that coincide with transient global warmings, or thermal maxima, including the Paleocene-Eocene Thermal Maximum (PETM). The CIE, which are recorded mainly in marine sedimentary sequences, have also been identified in continental sequences, occurred episodically, and yet appear to be paced or triggered by orbital forcing. To constrain the timing and scale of the CIE relative to long-term baseline variability, we have constructed a 4.52 million year (myr) long, high-resolution (~ 3 kyr) bulk sediment carbon isotope record spanning the lower Eocene to upper Paleocene (C25r-C24n) from a pelagic sediment section recovered at ODP Site 1262 in the southeast Atlantic. This section, which was orbitally-tuned utilizing high-resolution core log physical property and geochemical records, is the most stratigraphically complete upper Paleocene to lower Eocene sequence recovered to date. Time-series analysis of the carbon isotope record along with a high-resolution Fe intensity record obtained by XRF core scanner reveal cyclicity with variance concentrated primarily in the precession (21 kyr) and eccentricity bands (100 and 400-kyr) throughout the upper Paleocene-lower Eocene. In general, minima in δ 13C correspond with peaks in Fe (i.e., carbonate dissolution), both of which appear to be in phase with maxima in eccentricity. This covariance is consistent with excess oceanic uptake of isotopically depleted carbon resulting in lower carbonate saturation during periods of high eccentricity. This relationship includes all late Paleocene and early Eocene CIE confirming pacing by orbital forcing. The lone exception is the PETM, which appears to be out of phase with the 400-kyr cycle, though possibly in phase with the 100-kyr cycle, reinforcing the notion that a mechanism other than orbital forcing and/or an additional source of carbon is required to account for the

New data on Amynodontidae (Mammalia, Perissodactyla) from Eastern Europe: Phylogenetic and palaeobiogeographic implications around the Eocene-Oligocene transition.

Science.gov (United States)

Tissier, Jérémy; Becker, Damien; Codrea, Vlad; Costeur, Loïc; Fărcaş, Cristina; Solomon, Alexandru; Venczel, Marton; Maridet, Olivier

2018-01-01

Amynodontidae is a family of Rhinocerotoidea (Mammalia, Perissodactyla) known from the late Early Eocene to the latest Oligocene, in North America and Eurasia. European Amynodontidae are very rare, and all remains belong almost exclusively to a single post-Grande Coupure genus from the Oligocene, Cadurcotherium. The "Grande Coupure" defines an extinctions and dispersal-generated originations event in Europe that is nearly contemporaneous with the Eocene-Oligocene transition. Perissodactyls are one of the major groups affected by this event: Palaeotheriidae went almost extinct during this crisis, whereas Rhinocerotidae appeared for the first time in Europe. Study of fossiliferous Eastern-European localities from this age is crucial for the understanding of this crisis. We report here three new localities of Amynodontidae in Eastern Europe. Two of them are dated from the Eocene (Morlaca, Romania; Dorog, Hungary), whereas the other is either Late Eocene or Early Oligocene (Dobârca, Romania). The skull from this latter locality belongs unexpectedly to the same individual as a previously described mandible attributed to "Cadurcodon" zimborensis. As a result, this specimen can be allocated to its proper locality, Dobârca, and is assigned to a new genus, Sellamynodon gen. nov. It is characterised by an extraordinary growth of the nuchal crest, a unique character among amynodontids. Along with this remarkable material from Dobârca, two specimens from another Romanian locality, Morlaca, have been recently discovered and are dated from the Late Eocene. They belong, as well as new material from Dorog (Middle Eocene, Hungary), to the genus Amynodontopsis, also found in North America. The new Hungarian material represents the earliest occurrence of Amynodontidae in Europe. New phylogenetic hypotheses of Rhinocerotoidea are proposed, including the new material presented here, and show that Amynodontidae may be closer to the polyphyletic family 'Hyracodontidae' than to

Metasequoia glyptostroboides and its Utility in Paleoecological Reconstruction of Eocene High Latitude Forests

Science.gov (United States)

Williams, C. J.; LePage, B. A.; Vann, D. R.; Johnson, A. H.

2001-05-01

Abundant fossil plant remains are preserved in the Eocene-aged deposits of the Buchanan Lake formation on Axel Heiberg Island, Nunavut, Canada. Intact leaf litter, logs, and stumps preserved in situ as mummified remains present an opportunity to determine forest composition, structure, and productivity of a Taxodiaceae-dominated forest that once grew north of the Arctic Circle (paleolatitude 75-80° N). We excavated 37 tree stems for dimensional analysis from mudstone and channel-sand deposits. Stem length ranged from 1.0 m to 14.8 m (average = 3.2 m). Stem diameter ranged from less than 10 cm to greater than 75 cm (average = 32.2 cm). All stem wood was tentatively identified to genus as Metasequoia sp. The diameters and parabolic shape of the preserved tree trunks indicate that the Metasequoia were about 39 m tall across a wide range of diameters. The allometric relationships we derived for modern Metasequoia (n=70) allowed independent predictions of Metasequoia height given the stand density and stump diameters of the fossil forest. The two height estimates of 40 and 40.5 m match the results obtained from measurements of the Eocene trees. We used stump diameter data (n =107, diameter > 20 cm) and an uniform canopy height of 39 m to calculate parabolic stem volume and stem biomass for a 0.22 ha area of fossil forest. Stem volume equaled 2065 m3 ha-1 and stem biomass equaled 560 Mg ha-1 . In the Eocene forest, as determined from length of stems that were free of protruding branches and from 7 exhumed tree tops, the uppermost 9 m of the trees carried live branches with foliage. In living conifers, branch weights and the amount of foliage carried by branches are well correlated with branch diameters measured where the branch joins the main stem. To determine the biomass in branches and foliage in the Eocene forest, we used relationships derived from large modern Metasequoia. Based on the regression of branch weight v. branch diameter (r2 = 0.97) and foliar biomass v

Revised East-West Antarctic plate motions since the Middle Eocene

Science.gov (United States)

Granot, R.; Cande, S. C.; Stock, J.; Damaske, D.

2010-12-01

The middle Cenozoic (43-26 Ma) rifting between East and West Antarctica is defined by an episode of ultraslow seafloor spreading in the Adare Basin, located off northwestern Ross Sea. The absence of fracture zones and the lack of sufficient well-located magnetic anomaly picks have resulted in a poorly constrained kinematic model (Cande et al., 2000). Here we utilize the results from a dense aeromagnetic survey (Damaske et al., 2007) collected as part of GANOVEX IX 2005/06 campaign to re-evaluate the kinematics of the West Antarctic rift system since the Middle Eocene. We identify marine magnetic anomalies (anomalies 12o, 13o, 16y, and 18o) along a total of 25,000 km of the GPS navigated magnetic profiles. The continuation of these anomalies into the Northern Basin has allowed us to use the entire N-S length of this dataset in our calculations. A distinct curvature in the orientation of the spreading axis provides a strong constraint on our calculated kinematic models. The results from two- (East-West Antarctica) and three- (Australia-East Antarctica-West Antarctica) plate solutions agree well and create a cluster of rotation axes located south of the rift system, near the South Pole. These solutions reveal that spreading rate and direction, and therefore motion between East and West Antarctica, were steady between the Middle Eocene and Early Oligocene. Our kinematic solutions confirm the results of Davey and De Santis (2005) that the Victoria Land Basin has accommodated ~95 km of extension since the Middle Eocene. This magnetic pattern also provides valuable constraints on the post-spreading deformation of the Adare Basin (Granot et al., 2010). The Adare Basin has accommodated very little extension since the Late Oligocene (<7 km), but motion has probably increased southward. The details of this younger phase of motion are still crudely constrained.

Towards green loyalty: the influences of green perceived risk, green image, green trust and green satisfaction

Science.gov (United States)

Chrisjatmiko, K.

2018-01-01

The paper aims to present a comprehensive framework for the influences of green perceived risk, green image, green trust and green satisfaction to green loyalty. The paper also seeks to account explicitly for the differences in green perceived risk, green image, green trust, green satisfaction and green loyalty found among green products customers. Data were obtained from 155 green products customers. Structural equation modeling was used in order to test the proposed hypotheses. The findings show that green image, green trust and green satisfaction has positive effects to green loyalty. But green perceived risk has negative effects to green image, green trust and green satisfaction. However, green perceived risk, green image, green trust and green satisfaction also seems to be a good device to gain green products customers from competitors. The contributions of the paper are, firstly, a more complete framework of the influences of green perceived risk, green image, green trust and green satisfaction to green loyalty analyses simultaneously. Secondly, the study allows a direct comparison of the difference in green perceived risk, green image, green trust, green satisfaction and green loyalty between green products customers.

Primate tarsal bones from Egerkingen, Switzerland, attributable to the middle Eocene adapiform Caenopithecus lemuroides.

Science.gov (United States)

Seiffert, Erik R; Costeur, Loïc; Boyer, Doug M

2015-01-01

The middle Eocene species Caenopithecus lemuroides, known solely from the Egerkingen fissure fillings in Switzerland, was the first Paleogene fossil primate to be correctly identified as such (by Ludwig Rütimeyer in 1862), but has long been represented only by fragmentary mandibular and maxillary remains. More recent discoveries of adapiform fossils in other parts of the world have revealed Caenopithecus to be a biogeographic enigma, as it is potentially more closely related to Eocene adapiforms from Africa, Asia, and North America than it is to any known European forms. More anatomical evidence is needed, however, to provide robust tests of such phylogenetic hypotheses. Here we describe and analyze the first postcranial remains that can be attributed to C. lemuroides-an astragalus and three calcanei held in the collections of the Naturhistorisches Museum Basel that were likely recovered from Egerkingen over a century ago. Qualitative and multivariate morphometric analyses of these elements suggest that C. lemuroides was even more loris-like than European adapines such as Adapis and Leptadapis, and was not simply an adapine with an aberrant dentition. The astragalus of Caenopithecus is similar to that of younger Afradapis from the late Eocene of Egypt, and parsimony and Bayesian phylogenetic analyses that include the new tarsal data strongly support the placement of Afradapis and Caenopithecus as sister taxa to the exclusion of all other known adapiforms, thus implying that dispersal between Europe and Africa occurred during the middle Eocene. The new tarsal evidence, combined with previously known craniodental fossils, allows us to reconstruct C. lemuroides as having been an arboreal and highly folivorous 1.5-2.5 kg primate that likely moved slowly and deliberately with little or no capacity for acrobatic leaping, presumably maintaining consistent powerful grasps on branches in both above-branch and inverted postures.

Molecular and Morphological Evidence Challenges the Records of the Extant Liverwort Ptilidium pulcherrimum in Eocene Baltic Amber.

Science.gov (United States)

Heinrichs, Jochen; Scheben, Armin; Lee, Gaik Ee; Váňa, Jiří; Schäfer-Verwimp, Alfons; Krings, Michael; Schmidt, Alexander R

2015-01-01

Preservation of liverworts in amber, a fossilized tree resin, is often exquisite. Twenty-three fossil species of liverworts have been described to date from Eocene (35-50 Ma) Baltic amber. In addition, two inclusions have been assigned to the extant species Ptilidium pulcherrimum (Ptilidiales or Porellales). However, the presence of the boreal P. pulcherrimum in the subtropical or warm-temperate Baltic amber forest challenges the phytogeographical interpretation of the Eocene flora. A re-investigation of one of the fossils believed to be P. pulcherrimum reveals that this specimen in fact represents the first fossil evidence of the genus Tetralophozia, and thus is re-described here as Tetralophozia groehnii sp. nov. A second fossil initially assigned to P. pulcherrimum is apparently lost, and can be reassessed only based on the original description and illustrations. This fossil is morphologically similar to the extant North Pacific endemic Ptilidium californicum, rather than P. pulcherrimum. Divergence time estimates based on chloroplast DNA sequences provide evidence of a Miocene origin of P. pulcherrimum, and thus also argue against the presence of this taxon in the Eocene. Ptilidium californicum originated 25-43 Ma ago. As a result, we cannot rule out that the Eocene fossil belongs to P. californicum. Alternatively, the fossil might represent a stem lineage element of Ptilidium or an early crown group species with morphological similarities to P. californicum.

A new Late Eocene primate from the Krabi Basin (Thailand) and the diversity of Palaeogene anthropoids in southeast Asia.

Science.gov (United States)

Chaimanee, Yaowalak; Chavasseau, Olivier; Lazzari, Vincent; Euriat, Adélaïde; Jaeger, Jean-Jacques

2013-11-22

According to the most recent discoveries from the Middle Eocene of Myanmar and China, anthropoid primates originated in Asia rather than in Africa, as was previously considered. But the Asian Palaeogene anthropoid community remains poorly known and inadequately sampled, being represented only from China, Myanmar, Pakistan and Thailand. Asian Eocene anthropoids can be divided into two distinct groups, the stem group eosimiiforms and the possible crown group amphipithecids, but the phylogenetic relationships between these two groups are not well understood. Therefore, it is critical to understand their evolutionary history and relationships by finding additional fossil taxa. Here, we describe a new small-sized fossil anthropoid primate from the Late Eocene Krabi locality in Thailand, Krabia minuta, which shares several derived characters with the amphipithecids. It displays several unique dental characters, such as extreme bunodonty and reduced trigon surface area, that have never been observed in other Eocene Asian anthropoids. These features indicate that morphological adaptations were more diversified among amphipithecids than was previously expected, and raises the problem of the phylogenetic relations between the crown anthropoids and their stem group eosimiiforms, on one side, and the modern anthropoids, on the other side.

Astronomically forced paleoclimate change from middle Eocene to early Oligocene: continental conditions in central China compared with the global marine isotope record

Science.gov (United States)

Huang, C.; Hinnov, L. A.

2010-12-01

The early Eocene climatic optimum ended with a long interval of global cooling that began in the early Middle Eocene and ended at the Eocene-Oligocene transition. During this long-term cooling, a series of short-term warming reversals occurred in the marine realm. Here, we investigate corresponding continental climate conditions as revealed in the Qianjiang Formation of the Jianghan Basin in central China, which consists of more than 4000 m of saline lake sediments. The Qianjiang Formation includes, in its deepest sections, a halite-rich rhythmic sediment succession with dark mudstone, brownish-white siltstone and sandstone, and greyish-white halite. Alternating fresh water (humid/cool)—saline water (dry/hot) deposits reflect climate cycles driven by orbital forcing. High-resolution gamma ray (GR) logging from the basin center captures these pronounced lithological rhythms throughout the formation. Several halite-rich intervals are interpreted as short-term warming events within the middle Eocene to early Oligocene, and could be expressions of coeval warming events in the global marine oxygen isotope record, for example, the middle Eocene climate optimum (MECO) event around 41 Ma. The Eocene-Oligocene boundary is distinguished by a radical change from halite-rich to clastic sediments, indicating a dramatic climate change from warm to cool conditions. Power spectral analysis of the GR series indicates strong short (~100 kyr) eccentricity cycling during the warm/hot episodes. Amplitude modulation of the short eccentricity in the GR series occurs with a strong 405 kyr periodicity. This cycling is calibrated to the La2004 orbital eccentricity model. A climate reversal occurs at 36.5 Ma within the long-term marine cooling trend following MECO, which is reflected also in the Qianjiang GR series, with the latter indicating several brief warm/dry reversals within the trend. A ~2.6 Myr halite-rich warm interval occurs in the latest Eocene in the continental record; both

Green Street in District of Columbia Curbs Harmful Runoff

Science.gov (United States)

The name of the block hasn’t been changed to “Oh!” Street, but a revamped section of O Street NW in the District of Columbia is turning heads with green features that are keeping stormwater pollution out of the Anacostia River.

Rainforest conifers of Eocene Patagonia: attached cones and foliage of the extant Southeast Asian and Australasian genus Dacrycarpus (Podocarpaceae).

Science.gov (United States)

Wilf, Peter

2012-03-01

Eocene caldera-lake beds at Laguna del Hunco (LH, ca. 52.2 Ma) and Río Pichileufú (RP, ca. 47.7 Ma) in Argentine Patagonia provide copious information about the biological history of Gondwana. Several plant genera from these sites are known as fossils from southern Australia and New Zealand and survive only in Australasian rainforests. The potential presence of Dacrycarpus (Podocarpaceae) holds considerable interest due to its extensive foliage-fossil record in Gondwana, its remarkably broad modern distribution in Southeast Asian and Australasian rainforests, its high physiological moisture requirements, and its bird-dispersed seeds. However, the unique seed cones that firmly diagnose Dacrycarpus were not previously known from the fossil record. I describe and interpret fertile (LH) and vegetative (LH and RP) material of Dacrycarpus and present a nomenclatural revision for fossil Dacrycarpus from South America. Dacrycarpus puertae sp. nov. is the first fossil occurrence of the unusual seed cones that typify living Dacrycarpus, attached to characteristic foliage, and of attached Dacrycarpus pollen cones and foliage. Dacrycarpus puertae is indistinguishable from living D. imbricatus (montane, Burma to Fiji). Dacrycarpus chilensis (Engelhardt) comb. nov. is proposed for Eocene vegetative material from Chile. Modern-aspect Dacrycarpus was present in Eocene Patagonia, demonstrating an astonishingly wide-ranging paleogeographic history and implying a long evolutionary association with bird dispersers. Dacrycarpus puertae provides the first significant Asian link for Eocene Patagonian floras, strengthens the biogeographic connections from Patagonia to Australasia across Antarctica during the warm Eocene, and indicates high-rainfall paleoenvironments.

Magnetostratigraphy in the Lodo Formation, CA: An Attempt to Locate Hyperthermals of the Early Eocene

Science.gov (United States)

Aldrich, N. C.; Pluhar, C. J.; Gibbs, S.; Rieth, J. A.

2015-12-01

The Lodo Formation in the California Coast Range, Fresno County records the Paleocene Eocene Thermal Maximum (PETM) and possibly other Early Eocene hyperthermal events. The Eocene Thermal Maximum 2 (ETM2, ELMO, or H1) represents a hyperthermal event that occurred approximately 2 million years after the PETM and just prior to the C24r - C24n magnetic reversal (≈ 53.9 Ma) in the Ypresian. While the ETM2 event has been located in offshore samples, it has been more difficult to locate in a terrestrial section. This project attempts to locate the ETM2 magnetostratigraphically by finding the paleomagnetic reversal at C24r-C24n.3n, provide geochronological framework, and assess sedimentation rate changes during this time. This area is known to have had a high rate of deposition (16.8 cm/kyr ) during the PETM, which is found lower in the section. We collected 36 new samples from a 13.44m section spanning stratigraphy thought to cover the ETM2 along with 31 previous samples spanning the PETM, and prepared them for paleomagnetic and paleontological analysis. We analyzed samples using standard paleomagnetic methods including low-temperature and thermal demagnetization. Preliminary results suggest that the magnetostratigraphy spans the C24r-C24n boundary, while the micropaleontology shows the NP10-NP11 boundary, which occurs near the ETM2 as well as the NP11-NP12 boundary. The data indicate an order-of-magnitude drop in sedimentation rate in the lower Eocene at this site, concomitant with a drop in grain size, compared with the PETM.

Paleocene-Eocene Thermal Maximum and the Opening of the Northeast Atlantic

DEFF Research Database (Denmark)

Storey, Michael; Duncan, Robert A.; Swisher, III, Carl C.

2007-01-01

The Paleocene-Eocene thermal maximum (PETM) has been attributed to a sudden release of carbon dioxide and/or methane. 40Ar/39Ar age determinations show that the Danish Ash-17 deposit, which overlies the PETM by about 450,000 years in the Atlantic, and the Skraenterne Formation Tuff, representing ...

Single-crystal 40Ar/39Ar dating of the Eocene-Oligocene transition in North America

International Nuclear Information System (INIS)

Swisher, C.C. III; Prothero, D.R.

1990-01-01

Explanations for the causes of climatic changes and associated faunal and floral extinctions at the close of the Eocene Epoch have long been controversial because of, in part, uncertainties in correlation and dating of global events. New single-crystal laser fusion (SCLF) 40 Ar/ 39 Ar dates on tephra from key magnetostratigraphic and fossil-bearing sections necessitate significant revision in North American late Paleogene chronology. The Chadronian-Orellan North American Land Mammal Age boundary, as a result, is shifted from 32.4 to 34.0 Ma (million years ago), the Orellan-Whitneyan boundary is shifted from 30.8 to 32.0 Ma, and the Whitneyan-Arikareean boundary is now approximately 29.0 Ma. The new dates shift the correlation of Chron C12R from the Chadronian to within the Orellan-Whitneyan interval, the Chadronian becomes late Eocene in age, and the North American Oligocene is restricted to the Orellan, Whitneyan, and early Arikareean. The Eocene-Oligocene boundary, and its associated climate change and extinction events, as a result, correlates with the Chadronian-Orellan boundary, not the Duchesnean-Chadronian boundary. 30 refs., 1 fig., 1 tab

Orbitally forced Azolla blooms and Middle Eocene Arctic hydrology: Clues from palynology

NARCIS (Netherlands)

Barke, J.; Abels, H.A.; Sangiorgi, F.; Greenwood, D.R.; Sweet, A.R.; Donders, T.; Reichart, G.-J.; Lotter, A.F.; Brinkhuis, H.

2011-01-01

The high abundances and cyclic distribution of remains of the freshwater fern Azolla in early-Middle Eocene sediments from the Arctic Ocean have previously been related to episodic surface-water freshening, which was speculated to be orbitally modulated. Our integrated palynological and

Orbitally forced Azolla blooms And Middle Eocene Arctic hydrology: Clues from palynology

NARCIS (Netherlands)

Barke, J.; Abels, H.A.; Sangiorgi, F.; Greenwood, D.R.; Sweet, A.R.; Donders, T.; Reichart, G.-J.; Lotter, A.F.; Brinkhuis, H.

2011-01-01

The high abundances and cyclic distribution of remains of the freshwater fern Azolla in early-Middle Eocene sediments from the Arctic Ocean have previously been related to episodic surface-water freshening, which was speculated to be orbitally modulated. Our integrated palynological and

Eocene rotation of Sardinia, and the paleogeography of the western Mediterranean region

NARCIS (Netherlands)

Advokaat, Eldert; van Hinsbergen, D.J.J.|info:eu-repo/dai/nl/269263624; Maffione, M.; Langereis, C.G.|info:eu-repo/dai/nl/073584223; Vissers, R.L.M.|info:eu-repo/dai/nl/068789203; Cherchi, A.; Schroeder, R.; Madani, H.; Columbu, S.

2014-01-01

Key to understanding the complex Mediterranean subduction history is the kinematic reconstruction of its paleogeography after Jurassic extension between Iberia, Eurasia, and Africa. While post-Eocene Liguro-Provençal back-arc extension, and associated Miocene ~50° counterclockwise (ccw) rotation of

Early Eocene climatic optimum: Environmental impact on the North Iberian continental margin

NARCIS (Netherlands)

Payros, A.; Ortiz, S.; Millán, I.; Arostegi, J.; Orue-Etxebarria, X.; Apellaniz, E.

2015-01-01

The early Eocene climatic optimum, which constituted the peak of the long-term early Cenozoic global warming, had a significant impact on the environmental evolution of terrestrial and oceanic areas. Surprisingly, however, its influence on continental margins is poorly known. New insights are

Geological characteristic of the main oil and gas producing formations of the upper Austrian molasse basin. Pt. 1. The Eocene sandstones

Energy Technology Data Exchange (ETDEWEB)

Wagner, L [Rohoel-Aufsuchungs-Gesellschaft m.b.H., Vienna (Austria)

1980-09-01

The sandstones of the Upper Eocene are the main oil carriers within RAG's Upper Austrian concession area. The attempt is being made to reconstruct the paleogeography of the Eocene-in which time the sea transgressed the Molasse basin towards N and E - from core and log evidence. From deep Lower Tertiary onwards the mesozoic and older sediments were exposed to intensive erosion, which resulted in a slightly undulating peneplane sloping in a S to SW direction. This erosion plane was - still in Lower Tertiary times - in some areas dissected into horst and graben structures which greatly influenced the deposition of the early Eocene sediments. During the Upper Eocene the Molasse basin began to subside and subsided more strongly in the SW than in the N and NE, so that neritic deposits could form in the first area, whereas lagoonal and brackish sedimentation still prevailed in the latter. The Eocene sandstones are being classified according to their environment of deposition, and their reservoir, characteristics are being studied. Sandstones are absent in the neritic environment of the Discocyclina-marls only. Sand deposits have been encountered as: 1) transgressive horizons directly overlying the pretertiary substrate, 2) infills of channels cut into limnic-brackish sediments, 3) littoral deposits, partly interfingering with Lithothamnium limestone, 4) fine grained sandy marls and nummulitic sandstones within sublittoral to neritic sediments.

Refining the Early and Middle Eocene Geomagnetic Polarity Time Scale: new results from ODP Leg 208 (Walvis Ridge)

Science.gov (United States)

Westerhold, T.; Roehl, U.; Frederichs, T.; Bohaty, S. M.; Florindo, F.; Zachos, J. C.; Raffi, I.; Agnini, C.

2015-12-01

Astronomical calibration of the Geomagnetic Polarity Time Scale (GPTS) for the Eocene (34-56 Ma) has advanced tremendously in recent years. Combining a cyclostratigraphic approach based on the recognition of the stable 405-kyr eccentricity cycle of Earth's orbit with high-resolution bio- and magnetostratigraphy from deep-sea sedimentary records (ODP Legs 171B, 189 and 207; IODP Exp. 320/321) resulted in a new calibration of the middle-to-late Eocene GPTS spanning Chrons C12r to C19n (30.9-41.3 Ma). A fully astronomically calibrated GPTS for the Eocene was established recently by integrating cyclo-bio-magnetostratigraphy from ODP Sites 702 and 1263 records spanning the middle Eocene with Site 1258 records covering the early Eocene. Comparison of this deep sea-derived GPTS with GTS2012 and GPTS calibration points from terrestrial successions show overall consistent results, but there are still major offsets for the duration of Chrons C20r, C22r and C23n.2n. Because of the relatively large uncertainty of the calibration point, a radioisotopic dated ash layer in DSDP 516F, at C21n.75 (46.24±0.5 Ma) the duration of C20r in GPTS2012 (2.292 myr) is uncertain. Offsets in durations of C22r and C23n.2n between GPTS2012 and the new astronomical GPTS (~400-kyr longer C22r; ~400-kyr shorter C23n.2n) could be due to uncertainties in the interpretation of Site 1258 magnetostratigraphic data. Here we present new results toward establishing a more accurate and complete bio-, magneto- and chemostratigraphy for South Atlantic Leg 208 sites encompassing magnetochrons C13 to C24 (33 to 56 Ma). Our study aims to integrate paleomagnetic records from multiple drilled sites with physical property data, stable isotope data and XRF core scanning data to construct an astronomically calibrated framework for refining GPTS age estimates. This effort will complete the Early-to-Middle Eocene GPTS and allow evaluation of the relative position of calcareous nannofossil events to magnetostratigraphy.

Middle Eocene Climatic Optimum linked to continental arc flare-up in Iran?

Science.gov (United States)

van der Boon, A.; Kuiper, K.; van der Ploeg, R.; Cramwinckel, M.; Honarmand, M.; Sluijs, A.; Krijgsman, W.; Langereis, C. G.

2017-12-01

A 500 kyr episode of 3-5 °C gradual global climate warming, some 40 Myr ago, has been termed the Middle Eocene climatic optimum (MECO). It has been associated with a rise in atmospheric CO2 concentrations, but the source of this carbon remains enigmatic. We show, based on new Ar-Ar ages of volcanic rocks in Iran and Azerbaijan, that the time interval spanning the MECO was associated with a massive increase in continental arc volcanism. We also collected almost 300 Ar-Ar and U-Pb ages from literature. Typically, U-Pb ages from the Eocene are slightly younger, by 3 Myr, than Ar-Ar ages. We observed that U-Pb ages are obtained mostly from intrusive rocks and therefore must reflect an intrusive stage that post-dated extrusive volcanism. Combining all ages for extrusive rocks, we show that they cluster around 40.2 Ma, exactly within the time span of the MECO (40.5-40.0 Ma). We estimate volumes of volcanism based on a shapefile of outcrops and average thickness of the sequences. We calculate CO2 estimates using a relation volcanism-CO2 that was earlier used for the Deccan traps (Tobin et al., 2017). Our calculations indicate that the volume of the Iranian middle Eocene volcanic rocks (estimated at 37000 km3) is sufficient to explain the CO2 rise during the MECO. We conclude that continental arc flare-up in the Neotethys subduction zone is a plausible candidate for causing the MECO.

Atmospheric and oceanic impacts of Antarctic glaciation across the Eocene-Oligocene transition.

Science.gov (United States)

Kennedy, A T; Farnsworth, A; Lunt, D J; Lear, C H; Markwick, P J

2015-11-13

The glaciation of Antarctica at the Eocene-Oligocene transition (approx. 34 million years ago) was a major shift in the Earth's climate system, but the mechanisms that caused the glaciation, and its effects, remain highly debated. A number of recent studies have used coupled atmosphere-ocean climate models to assess the climatic effects of Antarctic glacial inception, with often contrasting results. Here, using the HadCM3L model, we show that the global atmosphere and ocean response to growth of the Antarctic ice sheet is sensitive to subtle variations in palaeogeography, using two reconstructions representing Eocene and Oligocene geological stages. The earlier stage (Eocene; Priabonian), which has a relatively constricted Tasman Seaway, shows a major increase in sea surface temperature over the Pacific sector of the Southern Ocean in response to the ice sheet. This response does not occur for the later stage (Oligocene; Rupelian), which has a more open Tasman Seaway. This difference in temperature response is attributed to reorganization of ocean currents between the stages. Following ice sheet expansion in the earlier stage, the large Ross Sea gyre circulation decreases in size. Stronger zonal flow through the Tasman Seaway allows salinities to increase in the Ross Sea, deep-water formation initiates and multiple feedbacks then occur amplifying the temperature response. This is potentially a model-dependent result, but it highlights the sensitive nature of model simulations to subtle variations in palaeogeography, and highlights the need for coupled ice sheet-climate simulations to properly represent and investigate feedback processes acting on these time scales. © 2015 The Author(s).

The formation of green rust induced by tropical river biofilm components

International Nuclear Information System (INIS)

Jorand, F.; Zegeye, A.; Ghanbaja, J.; Abdelmoula, M.

2011-01-01

In the Sinnamary Estuary (French Guiana), a dense red biofilm grows on flooded surfaces. In order to characterize the iron oxides in this biofilm and to establish the nature of secondary minerals formed after anaerobic incubation, we conducted solid analysis and performed batch incubations. Elemental analysis indicated a major amount of iron as inorganic compartment along with organic matter. Solid analysis showed the presence of two ferric oxides ferrihydrite and lepidocrocite. Bacteria were abundant and represented more than 10 11 cells g -1 of dry weight among which iron reducers were revealed. Optical and electronic microscopy analysis revealed than the bacteria were in close vicinity of the iron oxides. After anaerobic incubations with exogenous electron donors, the biofilm's ferric material was reduced into green rust, a Fe II -Fe III layered double hydroxide. This green rust remained stable for several years. From this study and previous reports, we suggest that ferruginous biofilms should be considered as a favorable location for GR biomineralization when redox conditions and electron donors availability are gathered. - Research highlights: → Characterization of ferruginous biofilm components by solid analysis methods. → Lepidocrocite and ferrihydrite were the main iron oxides. → Anaerobic incubation of biofilm with electron donors produced green rust. → Biofilm components promote the formation of the green rust. → Ferruginous biofilm could contribute to the natural mercury attenuation.

The formation of green rust induced by tropical river biofilm components

Energy Technology Data Exchange (ETDEWEB)

Jorand, F., E-mail: jorand@pharma.uhp-nancy.fr [Laboratoire de Chimie Physique et Microbiologie pour l' Environnement (LCPME) UMR 7564, CNRS-Nancy-Universite, Institut Jean Barriol, 405 rue de Vandoeuvre, F-54600 Villers-les Nancy (France); Zegeye, A. [Laboratoire de Chimie Physique et Microbiologie pour l' Environnement (LCPME) UMR 7564, CNRS-Nancy-Universite, Institut Jean Barriol, 405 rue de Vandoeuvre, F-54600 Villers-les Nancy (France); Ghanbaja, J. [Service Commun de Microscopies Electroniques et Microanalyses X (SCMEM), Nancy-Universite, Bvd des Aiguillettes, BP 239, 54506, Vandoeuvre-les-Nancy (France); Abdelmoula, M. [Laboratoire de Chimie Physique et Microbiologie pour l' Environnement (LCPME) UMR 7564, CNRS-Nancy-Universite, Institut Jean Barriol, 405 rue de Vandoeuvre, F-54600 Villers-les Nancy (France)

2011-06-01

In the Sinnamary Estuary (French Guiana), a dense red biofilm grows on flooded surfaces. In order to characterize the iron oxides in this biofilm and to establish the nature of secondary minerals formed after anaerobic incubation, we conducted solid analysis and performed batch incubations. Elemental analysis indicated a major amount of iron as inorganic compartment along with organic matter. Solid analysis showed the presence of two ferric oxides ferrihydrite and lepidocrocite. Bacteria were abundant and represented more than 10{sup 11} cells g{sup -1} of dry weight among which iron reducers were revealed. Optical and electronic microscopy analysis revealed than the bacteria were in close vicinity of the iron oxides. After anaerobic incubations with exogenous electron donors, the biofilm's ferric material was reduced into green rust, a Fe{sup II}-Fe{sup III} layered double hydroxide. This green rust remained stable for several years. From this study and previous reports, we suggest that ferruginous biofilms should be considered as a favorable location for GR biomineralization when redox conditions and electron donors availability are gathered. - Research highlights: {yields} Characterization of ferruginous biofilm components by solid analysis methods. {yields} Lepidocrocite and ferrihydrite were the main iron oxides. {yields} Anaerobic incubation of biofilm with electron donors produced green rust. {yields} Biofilm components promote the formation of the green rust. {yields} Ferruginous biofilm could contribute to the natural mercury attenuation.

Classification of Tropical River Using Chemometrics Technique: Case Study in Pahang River, Malaysia

International Nuclear Information System (INIS)

Mohd Khairul Amri Kamarudin; Mohd Ekhwan Toriman; Nur Hishaam Sulaiman

2015-01-01

River classification is very important to know the river characteristic in study areas, where this database can help to understand the behaviour of the river. This article discusses about river classification using Chemometrics techniques in mainstream of Pahang River. Based on river survey, GIS and Remote Sensing database, the chemometric analysis techniques have been used to identify the cluster on the Pahang River using Hierarchical Agglomerative Cluster Analysis (HACA). Calibration and validation process using Discriminant Analysis (DA) has been used to confirm the HACA result. Principal Component Analysis (PCA) study to see the strong coefficient where the Pahang River has been classed. The results indicated the main of Pahang River has been classed to three main clusters as upstream, middle stream and downstream. Base on DA analysis, the calibration and validation model shows 100 % convinced. While the PCA indicates there are three variables that have a significant correlation, domination slope with R"2 0.796, L/D ratio with R"2 -0868 and sinuosity with R"2 0.557. Map of the river classification with moving class also was produced. Where the green colour considered in valley erosion zone, yellow in a low terrace of land near the channels and red colour class in flood plain and valley deposition zone. From this result, the basic information can be produced to understand the characteristics of the main Pahang River. This result is important to local authorities to make decisions according to the cluster or guidelines for future study in Pahang River, Malaysia specifically and for Tropical River generally. The research findings are important to local authorities by providing basic data as a guidelines to the integrated river management at Pahang River, and Tropical River in general. (author)

A new avian fauna from the early-middle Eocene Lillebælt Clay Formation of Denmark

DEFF Research Database (Denmark)

Lindow, Bent Erik Kramer

A number of hitherto undescribed fossil bird remains have been recovered from the Lillebælt Clay Formation of central Denmark, which is early-middle Eocene in age (~50 to 43 mya). The core of the material consists of fossils acquired through the Danish ‘Danekræ' fossil treasure trove legislation......, a member of the extinct 'pseudo-toothed birds' and the first representative of this group known from Denmark. Other taxa present include remains of Lithornithidae and a new taxon possessing a massive, psittacid-like beak. The Lillebælt Clay Formation birds are temporally placed just after the Early Eocene...

The Eocene-Oligocene sedimentary record in the Chesapeake Bay impact structure: Implications for climate and sea-level changes on the western Atlantic margin

Science.gov (United States)

Schulte, P.; Wade, B.S.; Kontny, A.; ,

2009-01-01

A multidisciplinary investigation of the Eocene-Oligocene transition in the International Continental Scientific Drilling Program (ICDP)-U.S. Geological Survey (USGS) Eyreville core from the Chesapeake Bay impact basin was conducted in order to document environmental changes and sequence stratigraphic setting. Planktonic foraminifera and calcareous nannofossil biostratigraphy indicate that the Eyreville core includes an expanded upper Eocene (Biozones E15 to E16 and NP19/20 to NP21, respectively) and a condensed Oligocene-Miocene (NP24-NN1) sedimentary sequence. The Eocene-Oligocene contact corresponds to a =3-Ma-long hiatus. Eocene- Oligocene sedimentation is dominated by great diversity and varying amounts of detrital and authigenic minerals. Four sedimentary intervals are identified by lithology and mineral content: (1) A 30-m-thick, smectite- and illite-rich interval directly overlies the Exmore Formation, suggesting long-term reworking of impact debris within the Chesapeake Bay impact structure. (2) Subsequently, an increase in kaolinite content suggests erosion from soils developed during late Eocene warm and humid climate in agreement with data derived from other Atlantic sites. However, the kaolinite increase may also be explained by change to a predominant sediment input from outside the Chesapeake Bay impact structure caused by progradation of more proximal facies belts during the highstand systems tract of the late Eocene sequence E10.Spectral analysis based on gamma-ray and magnetic susceptibility logs suggests infl uence of 1.2 Ma low-amplitude oscillation of the obliquity period during the late Eocene. (3) During the latest Eocene (Biozones NP21 and E16), several lithological contacts (clay to clayey silt) occur concomitant with a prominent change in the mineralogical composition with illite as a major component: This lithological change starts close to the Biozone NP19/20-NP21 boundary and may correspond to sequence boundary E10-E11 as observed in

Modeling the influence of a reduced equator-to-pole sea surface temperature gradient on the distribution of water isotopes in the Eocene

Science.gov (United States)

Speelman, E. N.; Sewall, J. O.; Noone, D. C.; Huber, M.; Sinninghe Damsté, J. S.; Reichart, G.

2009-12-01

Proxy-based climate reconstructions suggest the existence of a strongly reduced equator-to-pole temperature gradient during most of the Early Eocene. With the realization that the Eocene Arctic Ocean was covered with enormous quantities of the free floating freshwater fern Azolla, new questions related to Eocene (global) hydrological cycling facilitating these blooms arose. Changes in hydrological cycling, as a consequence of a reduced temperature gradient, are expected to be most clearly reflected in the isotopic composition (D, 18O) of precipitation. The interpretation of water isotopic records to quantitatively estimate past precipitation patterns is, however, hampered by the lack of detailed information on changes in their spatial and temporal distribution. Using the isotope-enabled global circulation model, Community Atmosphere Model v.3 (isoCAM3), relationships between water isotopes and past climates can be simulated. Here we examine the influence of a reduced meridional sea surface temperature gradient on the spatial distribution of precipitation and its isotopic composition in an Eocene setting. Overall, our combination of Eocene climate forcings, with superimposed TEX86-derived SST estimates and elevated pCO2 concentrations, produces a climate that agrees well with proxy data in locations around the globe. It shows the presence of an intensified hydrological cycle with precipitation exceeding evaporation in the Arctic region. The Eocene model runs with a significantly reduced equator-to-pole temperature gradient in a warmer more humid world predict occurrence of less depleted precipitation, with δD values ranging only between 0 and -140‰ (as opposed to the present-day range of 0 to -300‰). Combining new results obtained from compound specific isotope analyses on terrestrially derived n-alkanes extracted from Eocene sediments, and model calculations, shows that the model not only captures the main features, but reproduces isotopic values

Hydrology, phosphorus, and suspended solids in five agricultural streams in the Lower Fox River and Green Bay Watersheds, Wisconsin, Water Years 2004-06

Science.gov (United States)

Graczyk, David J.; Robertson, Dale M.; Baumgart, Paul D.; Fermanich, Kevin J.

2011-01-01

A 3-year study was conducted by the U.S. Geological Survey and the University of Wisconsin-Green Bay to characterize water quality in agricultural streams in the Fox/Wolf watershed in northeastern Wisconsin and provide information to assist in the calibration of a watershed model for the area. Streamflow, phosphorus, and suspended solids data were collected between October 1, 2003, and September 30, 2006, in five streams, including Apple Creek, Ashwaubenon Creek, Baird Creek, Duck Creek, and the East River. During this study, total annual precipitation was close to the 30-year normal of 29.12 inches. The 3-year mean streamflow was highest in the East River (113 ft3/s), followed by Duck Creek (58.2 ft3/s), Apple Creek (26.9 ft3/s), Baird Creek (12.8 ft3/s), and Ashwaubenon Creek (9.1 ft3/s). On a yield basis, during these three years, the East River had the highest flow (0.78 ft3/s/mi2), followed by Baird Creek (0.61 ft3/s/mi2), Apple Creek (0.59 ft3/s/mi2), Duck Creek (0.54 ft3/s/mi2), and Ashwaubenon Creek (0.46 ft3/s/mi2). The overall median total suspended solids (TSS) concentration was highest in Baird Creek (73.5 mg/L), followed by Apple and Ashwaubenon Creeks (65 mg/L), East River (40 mg/L), and Duck Creek (30 mg/L). The median total phosphorus (TP) concentration was highest in Ashwaubenon Creek (0.60 mg/L), followed by Baird Creek (0.47 mg/L), Apple Creek (0.37 mg/L), East River (0.26 mg/L), and Duck Creek (0.22 mg/L).

A Phororhacoid bird from the Eocene of Africa

Science.gov (United States)

Mourer-Chauviré, Cécile; Tabuce, Rodolphe; Mahboubi, M'hammed; Adaci, Mohammed; Bensalah, Mustapha

2011-10-01

The bird fossil record is globally scarce in Africa. The early Tertiary evolution of terrestrial birds is virtually unknown in that continent. Here, we report on a femur of a large terrestrial new genus discovered from the early or early middle Eocene (between ˜52 and 46 Ma) of south-western Algeria. This femur shows all the morphological features of the Phororhacoidea, the so-called Terror Birds. Most of the phororhacoids were indeed large, or even gigantic, flightless predators or scavengers with no close modern analogs. It is likely that this extinct group originated in South America, where they are known from the late Paleocene to the late Pleistocene (˜59 to 0.01 Ma). The presence of a phororhacoid bird in Africa cannot be explained by a vicariant mechanism because these birds first appeared in South America well after the onset of the mid-Cretaceous Gondwana break up (˜100 million years old). Here, we propose two hypotheses to account for this occurrence, either an early dispersal of small members of this group, which were still able of a limited flight, or a transoceanic migration of flightless birds from South America to Africa during the Paleocene or earliest Eocene. Paleogeographic reconstructions of the South Atlantic Ocean suggest the existence of several islands of considerable size between South America and Africa during the early Tertiary, which could have helped a transatlantic dispersal of phororhacoids.

The Eocene Arctic Azolla bloom: environmental conditions, productivity and carbon drawdown.

Science.gov (United States)

Speelman, E N; Van Kempen, M M L; Barke, J; Brinkhuis, H; Reichart, G J; Smolders, A J P; Roelofs, J G M; Sangiorgi, F; de Leeuw, J W; Lotter, A F; Sinninghe Damsté, J S

2009-03-01

Enormous quantities of the free-floating freshwater fern Azolla grew and reproduced in situ in the Arctic Ocean during the middle Eocene, as was demonstrated by microscopic analysis of microlaminated sediments recovered from the Lomonosov Ridge during Integrated Ocean Drilling Program (IODP) Expedition 302. The timing of the Azolla phase (approximately 48.5 Ma) coincides with the earliest signs of onset of the transition from a greenhouse towards the modern icehouse Earth. The sustained growth of Azolla, currently ranking among the fastest growing plants on Earth, in a major anoxic oceanic basin may have contributed to decreasing atmospheric pCO2 levels via burial of Azolla-derived organic matter. The consequences of these enormous Azolla blooms for regional and global nutrient and carbon cycles are still largely unknown. Cultivation experiments have been set up to investigate the influence of elevated pCO2 on Azolla growth, showing a marked increase in Azolla productivity under elevated (760 and 1910 ppm) pCO2 conditions. The combined results of organic carbon, sulphur, nitrogen content and 15N and 13C measurements of sediments from the Azolla interval illustrate the potential contribution of nitrogen fixation in a euxinic stratified Eocene Arctic. Flux calculations were used to quantitatively reconstruct the potential storage of carbon (0.9-3.5 10(18) gC) in the Arctic during the Azolla interval. It is estimated that storing 0.9 10(18) to 3.5 10(18) g carbon would result in a 55 to 470 ppm drawdown of pCO2 under Eocene conditions, indicating that the Arctic Azolla blooms may have had a significant effect on global atmospheric pCO2 levels through enhanced burial of organic matter.

A new primate assemblage from La Verrerie de Roches (Middle Eocene, Switzerland).

Science.gov (United States)

Minwer-Barakat, Raef; Marigó, Judit; Becker, Damien; Costeur, Loïc

2017-12-01

Primates reached a great abundance and diversity during the Eocene, favored by warm temperatures and by the development of dense forests throughout the Northern Hemisphere. Here we describe new primate material from La Verrerie de Roches, a Middle Eocene karstic infill situated in the Jura Region (Switzerland), consisting of more than 80 dental remains. The primate assemblage from La Verrerie de Roches includes five different taxa. The best represented primate is Necrolemur aff. anadoni, similar in size and overall morphology to Necrolemur anadoni but resembling in some features the younger species Necrolemur antiquus. Microchoerines are also represented by two species of Pseudoloris, P. pyrenaicus and Pseudoloris parvulus, constituting the unique joint record of these two species known up to now. Remains of Adapiformes are limited to one isolated tooth of a large anchomomyin and another tooth belonging to the small adapine Microadapis cf. sciureus. The studied primate association allows assigning La Verrerie de Roches to the Robiacian Land Mammal Age. More specifically, this site can be confidently situated between the MP15 and MP16 reference levels, although the primate assemblage probably indicates some degree of temporal mixing. This is the first record of P. pyrenaicus and a form closely related to N. anadoni out of the Iberian Peninsula. The identification of these microchoerines in Switzerland gives further support to the connection of NE Spain and Central Europe during the Middle Eocene. Copyright © 2017 Elsevier Ltd. All rights reserved.

Review of the enigmatic Eocene shark genus Xiphodolamia (Chondrichthyes, Lamniformes) and description of a new species recovered from Angola, Iran and Jordan

Science.gov (United States)

Adnet, S.; Hosseinzadeh, R.; Antunes, M. T.; Balbino, A. C.; Kozlov, V. A.; Cappetta, H.

2009-10-01

Little is known about the extinct Xiphodolamia, a peculiar lamnid shark which inhabited the Eocene seas. The reexamination of a large set of fossilized teeth specimens from the Ypresian of Kazakhstan has enabled the reconstitution of the tooth series of this enigmatic taxa of lamnid shark. Five distinct tooth morphologies seem to occur in X. ensis Leidy [Leidy, J., 1877. Description of vertebrate remains, chiefly from the phosphate beds of South Carolina. Journal of the Academy of Natural Sciences of Philadelphia 8, 209-261] species revealing a weak ontogenetic variation. Such specific variation in tooth shape means that the other described species may be their junior synonyms. Dental morphology perfectly conforms with a Lamniforme but does not prove the current attribution to the Lamnidae family due to some inconsistent dental features observed, such as the presence of symphysial teeth. This genus could be regarded as an old lineage branched from the stem group of Lamnidae, close to the Isuroids sharks. Several Xiphodolamia teeth, originating both from old collections and new acquisitions, are reported and illustrated in order to provide information about a new species described here: Xiphodolamia serrata nov. sp. This species, currently limited to deposits in Angola, Jordan and Iran and dated at the Late Eocene, is easily distinguishable from the Early-Middle Eocene material belonging to the genus by the presence of serrated cutting edges. Adding to the type species considered here as the only valid taxa during the Early-Middle Eocene period, the temporal range of this genus extends to the Late Eocene, thus setting its upper stratigraphic limit prior to its disappearance as enigmatic as its appearance in the Early Eocene was.

The Middle and Upper Eocene sections of the Omsk trough, West Siberian Platform: Palynological, stratigraphic, hydrologic, and climatic aspects

Science.gov (United States)

Zaporozhets, N. I.; Akhmetiev, M. A.

2013-01-01

The thorough analysis and correlation of Middle-Upper Eocene sections in the Omsk trough (southern West Siberian Platform) recovered by Borehole 9 in its axial part near the Chistoozernoe Settlement (Novosibirsk region) and Borehole 8 on the southern limb near the Russkaya Polyana Settlement (southern Omsk region) revealed hiatuses at the base and top of the Russkaya Polyana Beds, a lithostratigraphic unit defined in the Lyulinvor Formation based on its substantially fine-grained composition and poor siliceous microplankton fossil remains. The overlying Tavda Formation (Middle-Upper Eocene) is traditionally accepted to consist of two subformations. The last formation was deposited in the West Siberian inner sea isolated from the Arctic basin. Particular attention is paid to eustatic sea level fluctuation especially during the period marked by accumulation of Azolla Beds under considerable desalination of surface waters in the basin. The curve of variations in the open sea factor based on the quantitative ratio between organic-walled phytoplankton fossils and higher plant palynomorphs is correlated with the modified version of the wellknown Vail curve. It is established that the West Siberian sea level experienced a brief rise in the terminal late Eocene prior to its complete desiccation at the Eocene-Oligocene transition because of global regression in response to glaciation in Antarctica.

Webspinners in Early Eocene amber from western India (Insecta, Embiodea

Directory of Open Access Journals (Sweden)

Michael Engel

2011-11-01

Full Text Available The family Scelembiidae (Neoembiodea: Embiomorpha: Archembioidea is recorded from Asia for the first time, based on two individuals preserved in Early Eocene amber from the Cambay Basin, western India. Kumarembia hurleyi Engel & Grimaldi, gen. n. et sp. n., is described, figured, and distinguished from other archembioid genera. The genus shares male genitalic features with scelembiids, otherwise known from South America and Africa.

River flow response to changes in vegetation cover in a South ...

African Journals Online (AJOL)

It was hypothesised in this study that annual river yield (river flow as a fraction of rainfall) in the Molenaars catchment near Paarl, South Africa co-varies with an index of green vegetation cover derived from satellite data (the normalised difference vegetation index, NDVI). The catchment was partitioned into 'upland' and ...

Organic Geochemistry and Rock-Eval Pyrolysis of Eocene fine Sediments, East Ketungau Basin, West Kalimantan

Directory of Open Access Journals (Sweden)

M.H. Hermiyanto Zajuli

2014-06-01

Full Text Available DOI: 10.17014/ijog.v6i2.119Indonesia contains many Paleogene and Neogene basins which some of them have been proven to be a very prolific producer of oil and gas. A study on the result of Rock-Eval pyrolysis and biomarker undertaken on the Eocene Mandai Group was able to assess hydrocarbon potential of the Paleogene fine sediments in the frontier basin, especially West Kalimantan area. East Ketungau Basin is located in the western Kalimantan, bounded with Melawi Basin by the Semitau High in the south and West Ketungau Basin in the west. The Mandai Group was deposited in the East Ketungau Basin during Eocene, consisting of sandstone and mudstone facies. Mudstone facies comprises shale, claystone, and coal. Seven samples of Eocene fine sediments collected from East Ketungau Basin were analyzed by Rock-Eval pyrolisis and three samples for biomarker to evaluate their hydrocarbon potential. The Rock-Eval pyrolisis result of Mandai Group shows that TOC value of this facies ranges from 0.34 % to 5.16 %, Potential Yield (PY between 0.06 and 4.78 mg HC/g rock, and Hydrogen Index (HI from 12 to 89. Based on that result, the fine sediments of Mandai Group are included into a gas prone source rock potential with poor to fair categories. Moreover Tmax values vary from 426o C to 451o C. The Eocene fine sediments of Mandai Group fall under kerogen type III. Based on Tmax and biomarker analyses, the maturity of the sediments is situated within immature to mature level. The fine sediments of Mandai Group were deposited in a terrestrial to marine environment under anoxic to sub-oxic condition.

A new miniaturized lizard from the late Eocene of France and Spain.

Science.gov (United States)

Bolet, Arnau; Augé, Marc

2014-03-01

We report here a new lizard genus and species shared by two late Eocene localities situated at both versants of the present Pyrenees (South-Western Europe), one located in France (Escamps, MP19), and the other in Catalonia, Spain (Sossís, MP17a). The recovered specimens are remarkable because of their small size and peculiar morphology. Features of the dentary are interpreted as adaptations to a fossorial or semi-fossorial lifestyle, although such modifications obscure the exact phylogenetic relationships of the new taxon. We suggest that it might represent a further example of scincoid lizard that independently achieved adaptations for burrowing or surface-dwelling. This taxon reinforces the hypotheses that link the Southern Pyrenean assemblages to those from France rather than to those of the rest of the Iberian Peninsula, which are supposed to be somehow isolated and endemic to a certain degree during the middle and late Eocene, forming part of the so-called Western Iberian Bioprovince. Copyright © 2014 Wiley Periodicals, Inc.

Comprehensive flood mitigation and management in the Chi River Basin, Thailand

OpenAIRE

Kunitiyawichai, K.; Schultz, B.; Uhlenbrook, S.; Suryadi, F.X.; Corzo, G.A.

2011-01-01

Severe flooding of the flat downstream area of the Chi River Basin occurs frequently. This flooding is causing catastrophic loss of human lives, damage and economic loss. Effective flood management requires a broad and practical approach. Although flood disasters cannot completely be prevented, major part of potential loss of lives and damages can be reduced by comprehensive mitigation measures. In this paper, the effects of river normalisation, reservoir operation, green river (bypass), and ...

Winged fruits and associated leaves of Shorea (Dipterocarpaceae) from the Late Eocene of South China and their phytogeographic and paleoclimatic implications.

Science.gov (United States)

Feng, Xinxin; Tang, Biao; Kodrul, Tatiana M; Jin, Jianhua

2013-03-01

Dipterocarps are the representative component of tropical rain forests in Southeast Asia and hold important economic and ecological significance, but their origin and migration are controversial. Information on dipterocarpaceous fossils, particularly the more convincing reproductive structures, not only can improve the phylogenetic and phytogeographic studies of this family, but also provide important information for reconstructing paleoclimate. • Morphologically preserved winged fruits and associated leaves were collected from the Late Eocene Huangniuling Formation, Maoming Basin, South China. We determined their taxonomic positions based on comparative morphology with similar extant and fossil specimens and discuss their phytogeographic and paleoclimatic implications by consulting the distribution and habitat of fossil and modern populations. • The Late Eocene winged fruits are attributed to Shorea Roxburgh ex Gaertner (Dipterocarpaceae) as Shorea maomingensis sp. nov. The associated leaves are recognized as Shorea sp. based on leaf architecture, and they are likely to be conspecific with the winged fruits. • The discovery of dipterocarps indicates that they had arrived in tropical and humid South China by the Late Eocene. Dipterocarps including Shorea exhibit a wide range of physiological tolerance to climate; palynological analysis suggests an increase in aridity and seasonality in the Maoming Basin from the Late Eocene. Dipterocarps became adapted to this seasonal climate from the Late Eocene to Early Miocene, expanded northward in the climatic optimum of the Middle Miocene, and declined and gradually disappeared from the southeastern part of the continent from the Late Miocene.

Convective nature of the planimetric instability in meandering river dynamics.

Science.gov (United States)

Camporeale, Carlo; Ridolfi, Luca

2006-02-01

The convective nature of the linear instability of meandering river dynamics is analytically demonstrated and the corresponding Green's function is derived. The wave packet due to impulsive disturbance migrates along a river either downstream or upstream, depending on the subresonant or superresonant conditions. The influence of the parameters that govern the meandering process is shown and the role of the fluid dynamic detail used to describe the morphodynamic problem is discussed. A numerical simulation of the river planimetry is also developed.

Astrochronology of extreme global warming events during the early Eocene greenhouse climate

NARCIS (Netherlands)

Lauretano, V.

2016-01-01

The early Eocene represents an ideal case study to analyse the impact of enhanced global warming on the ocean-atmosphere system and the relationship between carbon cycling and climate. During this time interval, the Earth’s surface experienced a long-term warming trend that culminated in a period of

Palaeointensity determinations and magnetic properties on Eocene rocks from Izu-Bonin-Mariana forearc (IODP Exp. 352)

Science.gov (United States)

Carvallo, C.; Camps, P.; Sager, W. W.; Poidras, T.

2017-09-01

IODP Expedition 352 cored igneous rocks from the Izu-Bonin-Mariana forearc crust. Cores from Sites U1440 and U1441 recovered Eocene basalts and related rocks and cores from Sites U1439 and U1442 recovered Eocene boninites and related rocks. We selected samples from Holes U1439C, U1440B and U1442A for palaeointensity measurements. Hysteresis measurements and high and low-temperature magnetization curves show that samples from Hole U1440B undergo magneto-chemical changes when heated and are mostly composed of single-domain (SD) or pseudo-single-domain (PSD) titanomaghemite. In contrast, the same measurements show that most selected samples from Holes U1439C and U1442A are thermally stable and are composed of either SD or PSD titanomagnetite with very little titanium content, or SD ferromagnetic grains with a large paramagnetic contribution. Thellier-Thellier palaeointensity experiments carried out on U1439C and U1442A samples give a good success rate of 25/60 and Virtual Dipole Moment (VDM) values between 1.3 and 3.5 × 1022 Am2. Multispecimen palaeointensity experiments with the domain-state corrected method carried out on 55 samples from Hole U1440B (divided into four groups) and 20 from Hole U1439C gave poor quality results, but indicated a VDM around 4-6 × 1022 Am2 in Hole U1440B forearc basalts. These results are in agreement with the few, low VDM values previously measured on Eocene rocks. However, they do not support an inverse relationship between field intensity and reversal rate for this period of time, since the Eocene reversal rate was low.

Experience in well logging study of Eocene deposits at the territory of Central and West Azerbaijan

International Nuclear Information System (INIS)

Shilov, G.Ya.; Makhmudova, V.M.; Agabekova, L.A.

1989-01-01

Experience of investigation of Eocene deposits in Azerbaijan by well-logging methods (WLM), including gamma-logging (GL), neutron gamma-logging (NGL), gamma-gamma logging (GGL), is generalized. Clay rocks are characterized by the maximal NGL and GL values, tuff sandstones - by the average NGL values. NGL and GGL data are used to determine porosity of strata. Complex interpretation of WLM data enables to obtain reliable evaluations of lithology, porosity and oil saturation of Eocene rocks. Algorithm of quantitative interpretation of WLM materials is suggested. Efficiency of WLM interpretation was equal to 95 %. Since the suggested algorithm is formalized completely, it can be realized in systems of complex WLM interpretation by computer

Late Eocene Inversion and Exhumation of the Sivas Basin (Central Anatolia) Based On Low-Temperature Thermochronometry: Implications for Diachronous Initiation of Arabia-Eurasia Collision

Science.gov (United States)

Darin, M. H.; Umhoefer, P. J.; Thomson, S. N.; Schleiffarth, W. K.

2017-12-01

The timing of initial Arabia-Eurasia collision along the Bitlis-Zagros suture is controversial, with widely varying estimates from middle Eocene to late Miocene ( 45-10 Ma). The Cenozoic Sivas Basin (central Anatolia) preserves a detailed record of the initial stages of Arabia collision directly north of the suture in the Eurasian foreland. New apatite fission track and (U-Th)/He thermochronology data from Late Cretaceous to Paleogene units indicate rapid basin inversion and initiation of the north-vergent Southern Sivas Fold and Thrust Belt (SSFTB) during the late Eocene to early Oligocene ( 40-30 Ma), consistent with the age of a basin-wide unconformity and switch from marine to nonmarine sedimentation. We interpret late Eocene exhumation and the predominantly north-vergent kinematics of the SSFTB to reflect northward propagation of contraction into the Sivas retro-foreland basin due to initial collision of the Arabian passive margin with the Anatolide-Tauride block along the southern Eurasian margin during the late middle Eocene. We test this hypothesis by comparing our new results with regional-scale compilations of both published thermochronology and geochronology data from the entire Arabia-Eurasia collision zone. Low-temperature thermochronology data from eastern Anatolia, the Caucasus, Zagros, and Alborz demonstrate that rapid cooling and intraplate deformation occurred across much of the Eurasian foreland during the middle Eocene to early Oligocene ( 45-30 Ma). Our regional compilation of published geochronology data from central and eastern Anatolia reveals a distinct magmatic lull during the latest Eocene, Oligocene, and earliest Miocene (ca. 38-20 Ma), slightly earlier than a diachronous magmatic lull initiating at 25-5 Ma from northwest to southeast in Iran (Chiu et al., 2013). These results support a tectonic model for diachronous collision in which initial collision of the Arabia promontory occurred in central-eastern Anatolia during the middle

The Eocene-Oligocene transition in the North Alpine Foreland Basin and subsequent closure of a Paratethys gateway

Science.gov (United States)

van der Boon, A.; Beniest, A.; Ciurej, A.; Gaździcka, E.; Grothe, A.; Sachsenhofer, R. F.; Langereis, C. G.; Krijgsman, W.

2018-03-01

During the Eocene-Oligocene transition (EOT), a major palaeoenvironmental change took place in the Paratethys Sea of central Eurasia. Restricted connectivity and increased stratification resulted in wide-spread deposition of organic-rich sediments which nowadays make up important hydrocarbon source rocks. The North Alpine Foreland Basin (NAFB) was a major gateway of the Paratethys Sea to the open ocean during the Eocene, but the age of closure of this gateway is still uncertain. The Ammer section in southern Germany documents the shallowing of this connection and subsequent disappearance of marine environments in the NAFB, as reflected in its sedimentary succession of turbidites to marls (Deutenhausen to Tonmergel beds), via coastal sediments (Baustein beds) to continental conglomerates (Weißach beds). Here, we apply organic geochemistry and date the lithological transitions in the Ammer section using integrated stratigraphy, including magnetostratigraphy and biostratigraphy. Nannoplankton and dinocyst results can be reconciled when dinoflagellate species Wetzeliella symmetrica is of late Eocene age. Our magnetostratigraphy then records C13r-C13n-C12r and allows calculation of sediment accumulation rates and estimation of ages of lithological transitions. We show that the shallowing from turbiditic slope deposits (Deutenhausen beds) to shelf sediments (Tonmergel beds) coincides with the Eocene-Oligocene boundary at 33.9 Ma. The transition to continental sediments is dated at ca. 33.15 Ma, significantly older than suggested by previous studies. We conclude that the transition from marine to continental sediments drastically reduced the marine connection through the western part of the NAFB and influenced the oxygen conditions of the Paratethys Sea.

Some new Eocene elasmobranch reports from the outer Western Carpathians (Moravia, Czech Republic)

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš; Skupien, P.

2013-01-01

Roč. 268, č. 1 (2013), s. 113-123 ISSN 0077-7749 Institutional research plan: CEZ:AV0Z30130516 Institutional support: RVO:67985831 Keywords : Elasmobranchii * Leidybatis jugossus * Centrophorus * Eocene * Western Carpathian Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.541, year: 2013

Two new parrots (Psittaciformes) from the Lower Eocene Fur Formation of Denmark

DEFF Research Database (Denmark)

Waterhouse, David; Lindow, Bent Erik Kramer; Zelenkov, Nikita

2008-01-01

Two new fossil psittaciform birds from the Lower Eocene ‘Mo Clay' (Fur Formation) of Denmark (c. 54 Ma) are described. An unnamed specimen is assigned to the extinct avian family of stem-group parrots, Pseudasturidae (genus and species incertae sedis), while a second (Mopsitta tanta gen. et sp. nov...

Modeling the influence of a reduced equator-to-pole sea surface temperature gradient on the distribution of water isotopes in the Early/Middle Eocene

Science.gov (United States)

Speelman, Eveline N.; Sewall, Jacob O.; Noone, David; Huber, Matthew; von der Heydt, Anna; Damsté, Jaap Sinninghe; Reichart, Gert-Jan

2010-09-01

Proxy-based climate reconstructions suggest the existence of a strongly reduced equator-to-pole temperature gradient during the Azolla interval in the Early/Middle Eocene, compared to modern. Changes in the hydrological cycle, as a consequence of a reduced temperature gradient, are expected to be reflected in the isotopic composition of precipitation (δD, δ 18O). The interpretation of water isotopic records to quantitatively reconstruct past precipitation patterns is, however, hampered by a lack of detailed information on changes in their spatial and temporal distribution. Using the isotope-enabled version of the National Center for Atmospheric Research (NCAR) atmospheric general circulation model, Community Atmosphere Model v.3 (isoCAM3), relationships between water isotopes and past climates can be simulated. Here we examine the influence of an imposed reduced meridional sea surface temperature gradient on the spatial distribution of precipitation and its isotopic composition in an Early/Middle Eocene setting. As a result of the applied forcings, the Eocene simulation predicts the occurrence of less depleted high latitude precipitation, with δD values ranging only between 0 and -140‰ (compared to Present-day 0 to -300‰). Comparison with Early/Middle Eocene-age isotopic proxy data shows that the simulation accurately captures the main features of the spatial distribution of the isotopic composition of Early/Middle Eocene precipitation over land in conjunction with the aspects of the modeled Early/Middle Eocene climate. Hence, the included stable isotope module quantitatively supports the existence of a reduced meridional temperature gradient during this interval.

Evolution of tertiary intermontane fluvial system of Powder River Basin, Wyoming and Montana

International Nuclear Information System (INIS)

Flores, R.M.; Ethridge, F.G.

1985-01-01

Exploration and development of economic coal and uranium deposits of the Tertiary Fort Union and Wasatch Formations provided data related to the evolution of depositional systems in the Powder River Basin. In ascending order, the Paleocene Fort Union Formation consists of the Tullock, Lebo, and Tongue River Members. The overlying Eocene Wasatch Formation consists of the conglomeratic Kingsbury and Moncrief Members and laterally equivalent finer grained deposits. Evolution of fluvial deposition in the basin was determined from sandstone percent maps. A high proportion of sandstones in the Tullock Member and combined Tongue River Member and Wasatch Formation formed in interconnected east-west and north-south belts. The east-west belts represent alluvial fans, as well as braided and meandering tributary streams. The north-south belts reflect meandering and anastomosing trunk streams fed by basin margin tributaries. The sandstones of the Lebo Shale show east-west trends and represent deposits of fluvio-deltaic systems that filled a western, closed-lacustrine basin. The lake in this basin may have formed during localized subsidence along the Buffalo deep fault. These contrasting styles of fluvial deposition were largely controlled by extrabasinal and intrabasinal tectonics associated with Laramide orogeny

Subtropical Arctic Ocean temperatures during the Palaeocene/Eocene thermal maximum

Science.gov (United States)

Sluijs, A.; Schouten, S.; Pagani, M.; Woltering, M.; Brinkhuis, H.; Damste, J.S.S.; Dickens, G.R.; Huber, M.; Reichart, G.-J.; Stein, R.; Matthiessen, J.; Lourens, L.J.; Pedentchouk, N.; Backman, J.; Moran, K.; Clemens, S.; Cronin, T.; Eynaud, F.; Gattacceca, J.; Jakobsson, M.; Jordan, R.; Kaminski, M.; King, J.; Koc, N.; Martinez, N.C.; McInroy, D.; Moore, T.C.; O'Regan, M.; Onodera, J.; Palike, H.; Rea, B.; Rio, D.; Sakamoto, T.; Smith, D.C.; St John, K.E.K.; Suto, I.; Suzuki, N.; Takahashi, K.; Watanabe, M. E.; Yamamoto, M.

2006-01-01

The Palaeocene/Eocene thermal maximum, ???55 million years ago, was a brief period of widespread, extreme climatic warming, that was associated with massive atmospheric greenhouse gas input. Although aspects of the resulting environmental changes are well documented at low latitudes, no data were available to quantify simultaneous changes in the Arctic region. Here we identify the Palaeocene/Eocene thermal maximum in a marine sedimentary sequence obtained during the Arctic Coring Expedition. We show that sea surface temperatures near the North Pole increased from ???18??C to over 23??C during this event. Such warm values imply the absence of ice and thus exclude the influence of ice-albedo feedbacks on this Arctic warming. At the same time, sea level rose while anoxic and euxinic conditions developed in the ocean's bottom waters and photic zone, respectively. Increasing temperature and sea level match expectations based on palaeoclimate model simulations, but the absolute polar temperatures that we derive before, during and after the event are more than 10??C warmer than those model-predicted. This suggests that higher-than-modern greenhouse gas concentrations must have operated in conjunction with other feedback mechanisms-perhaps polar stratospheric clouds or hurricane-induced ocean mixing-to amplify early Palaeogene polar temperatures. ?? 2006 Nature Publishing Group.

The Eocene climate of China, the early elevation of the Tibetan Plateau and the onset of the Asian Monsoon.

Science.gov (United States)

Wang, Qing; Spicer, Robert A; Yang, Jian; Wang, Yu-Fei; Li, Cheng-Sen

2013-12-01

Eocene palynological samples from 37 widely distributed sites across China were analysed using co-existence approach to determine trends in space and time for seven palaeoclimate variables: Mean annual temperature, mean annual precipitation, mean temperature of the warmest month, mean temperature of the coldest month, mean annual range of temperature, mean maximum monthly precipitation and mean minimum monthly precipitation. Present day distributions and observed climates within China of the nearest living relatives of the fossil forms were used to find the range of a given variable in which a maximum number of taxa can coexist. Isotherm and isohyet maps for the early, middle and late Eocene were constructed. These illustrate regional changing patterns in thermal and precipitational gradients that may be interpreted as the beginnings of the modern Asian Monsoon system, and suggest that the uplift of parts of the Tibetan Plateau appear to have taken place by the middle to late Eocene. © 2013 John Wiley & Sons Ltd.

Study of a conceptual nuclear energy center at Green River, Utah. Final summary report

Energy Technology Data Exchange (ETDEWEB)

Williams, J.T. (ed.)

1982-09-01

This document summarizes a conceptual study on the feasibility and practicality of developing a nuclear energy center (NEC) at a representative Western site. The site selected for this conceptual study, an area of about 50 square miles, is located 15 miles south of Green River, Utah. The conceptual NEC would consist of nine nuclear electric generating units, arranged on the site in three clusters of three reactors each (triads), separated by about 2 1/2 miles. Of the total electric output of 11,250 MWe that the NEC could produce, about 82% is assumed to be transmitted out of Utah to Colorado, New Mexico, Arizona, Nevada, and California. The technical engineering issues studied included geology and seismology, plant design, low-level radioactive waste disposal, transmission, and construction schedules and costs. Socioeconomic issues included were demographics, land use, community service needs, and fiscal impacts. Environmental considerations included terrestrial and aquatic ecology, visual impact, and secondary population impacts. Radiological issues were concerned with the safety and risks of an NEC and an on-site low-level waste facility. Institutional issues included methods of ownership, taxation, implications of energy export, and water allocation. The basic finding was that an NEC would be technically feasible, but a number of socioeconomic and institutional issues would require resolution before a Western regional NEC could be considered a viable power plant siting option.

Study of a conceptual nuclear energy center at Green River, Utah. Final summary report

International Nuclear Information System (INIS)

Williams, J.T.

1982-09-01

This document summarizes a conceptual study on the feasibility and practicality of developing a nuclear energy center (NEC) at a representative Western site. The site selected for this conceptual study, an area of about 50 square miles, is located 15 miles south of Green River, Utah. The conceptual NEC would consist of nine nuclear electric generating units, arranged on the site in three clusters of three reactors each (triads), separated by about 2 1/2 miles. Of the total electric output of 11,250 MWe that the NEC could produce, about 82% is assumed to be transmitted out of Utah to Colorado, New Mexico, Arizona, Nevada, and California. The technical engineering issues studied included geology and seismology, plant design, low-level radioactive waste disposal, transmission, and construction schedules and costs. Socioeconomic issues included were demographics, land use, community service needs, and fiscal impacts. Environmental considerations included terrestrial and aquatic ecology, visual impact, and secondary population impacts. Radiological issues were concerned with the safety and risks of an NEC and an on-site low-level waste facility. Institutional issues included methods of ownership, taxation, implications of energy export, and water allocation. The basic finding was that an NEC would be technically feasible, but a number of socioeconomic and institutional issues would require resolution before a Western regional NEC could be considered a viable power plant siting option

Astronomically paced middle Eocene deepwater circulation in the western North Atlantic

Science.gov (United States)

Vahlenkamp, Maximilian; Niezgodzki, Igor; De Vleeschouwer, David; Bickert, Torsten; Harper, Dustin; Lohmann, Gerrit; Pälike, Heiko; Zachos, James C.

2017-04-01

The role of the Atlantic Meridional Overturning Circulation (AMOC) as a key player for abrupt climatic changes (e.g. Heinrich Stadials) during the Pleistocene is relatively well constrained. However, the timing of the onset of a „modern" North Atlantic Deepwater (NADW) formation are still debated: Recent estimates range from the middle Miocene to the Early Eocene [Davies et al., 2001, Stoker et al., 2005, Hohbein et al., 2012] and are mainly based on the seismic interpretation contourite drifts. Another understudied aspect of the AMOC is its behavior during climatic variations on orbital time scales and under different climatic boundary conditions (icehouse vs hothouse). IODP Expedition 342 drilled carbonate-rich sequences from sediment drifts offshore Newfoundland that cover the middle Eocene with high sedimentation rates ( 3 cm/ kyr). We present a 2 Myr long stable carbon and oxygen isotope record of benthic foraminifera nuttalides truempyi spanning magnetochron C20r in unprecedented resolution (Petroleum Geology, v. 22, no. 9, p. 977-1005. Hohbein, M. W., Sexton, P. F., and Cartwright, J. A., 2012, Onset of North Atlantic Deep Water production coincident with inception of the Cenozoic global cooling trend: Geology, v. 40, no. 3, p. 255-258.

Using Detrital Zircon Geochronology to Constrain Paleogene Provenance and Its Relationship to Rifting in the Zhu 1 Depression, Pearl River Mouth Basin, South China Sea

Science.gov (United States)

Wang, Wei; Ye, Jiaren; Bidgoli, Tandis; Yang, Xianghua; Shi, Hesheng; Shu, Yu

2017-11-01

Paleogene syn-rift successions in the South China Sea are poorly understood and systematic provenance analysis, which could provide clues to their history, is lacking. Here we report 409 new concordant U-Pb ages from detrital zircons separated from the Paleogene Wenchang, Enping, and Zhuhai formations in the Zhu 1 depression, Pearl River Mouth Basin. The new data, combined with the published age data from the region, document changes in the provenance of syn-rift successions. Detrital zircons from the Eocene Wenchang Formation are unimodal, with Jurassic-Cretaceous (180-80 Ma) ages making up >80% of grains. The ages are consistent with the geochronology of intrabasinal highs, dominated by igneous rocks emplaced during the Yanshanian orogeny, and suggest local provenance. By contrast, detrital zircons from the upper Eocene to lower Oligocene Enping Formation form three well-recognized age-clusters, with peaks at 150, 254, and 438 Ma that match documented tectonomagmatism in South China Block (SCB). Combined with increasing numbers of Precambrian zircons, the data suggest increasing influence of regional provenance of the SCB. Similar age peaks are also recognized from the limited number of zircons analyzed from the upper Oligocene Zhuhai Formation and comparability with modern shelf and river sediment indicates the unit was mainly sourced from the SCB and likely transported by a paleo-Pearl River. We infer that the change in provenance, from local uplifts within the Zhu 1 to the SCB, is related to distinct phases of PRMB rift development; however, later changes are best explained by SCB drainage evolution.

The evolution of the Antarctic ice sheet at the Eocene-Oligocene Transition.

Science.gov (United States)

Ladant, Jean-Baptiste; Donnadieu, Yannick; Dumas, Christophe

2017-04-01

An increasing number of studies suggest that the Middle to Late Eocene has witnessed the waxing and waning of relatively small ephemeral ice sheets. These alternating episodes culminated in the Eocene-Oligocene transition (34 - 33.5 Ma) during which a sudden and massive glaciation occurred over Antarctica. Data studies have demonstrated that this glacial event is constituted of two 50 kyr-long steps, the first of modest (10 - 30 m of equivalent sea level) and the second of major (50 - 90 m esl) glacial amplitude, and separated by 200 kyrs. Since a decade, modeling studies have put forward the primary role of CO2 in the initiation of this glaciation, in doing so marginalizing the original "gateway hypothesis". Here, we investigate the impacts of CO2 and orbital parameters on the evolution of the ice sheet during the 500 kyrs of the EO transition using a tri-dimensional interpolation method. The latter allows precise orbital variations, CO2 evolution and ice sheet feedbacks (including the albedo) to be accounted for. Our results show that orbital variations are instrumental in initiating the first step of the EO glaciation but that the primary driver of the major second step is the atmospheric pCO2 crossing a modelled glacial threshold of 900 ppm. Although model-dependant, this higher glacial threshold makes a stronger case for ephemeral Middle-Late Eocene ice sheets. In addition, sensitivity tests demonstrate that the small first step only exists if the absolute pCO2 value remains within 100 ppm higher than the glacial threshold during the first 250 kyrs of the transition. Thereby, the pCO2 sufficiently counterbalances the strong insolation minima occurring at 33.9 and 33.8 Ma but is low enough to allow the ice sheet to nucleate. Nevertheless, questions remain as to what may cause this pCO2 drop.

An antarctic stratigraphic record of stepwise ice growth through the eocene-oligocene transition

NARCIS (Netherlands)

Passchier, Sandra; Ciarletta, Daniel J.; Miriagos, Triantafilo E.; Bijl, Peter K.; Bohaty, Steven M.

2017-01-01

Earth's current icehouse phase began ~34 m.y. ago with the onset of major Antarctic glaciation at the Eocene-Oligocene transition. Changes in ocean circulation and a decline in atmospheric greenhouse gas levels were associated with stepwise cooling and ice growth at southern high latitudes. The

New stalked and sessile cirripedes from the Eocene Mo Clay, northwest Jutland (Denmark)

DEFF Research Database (Denmark)

Carriol, René-Pierre; Bonde, Niels Christensøn; Jakobsen, Sten Lennart

2016-01-01

New taxa of thoracican cirripedes are recorded from the Eocene Mo Clay of northwest Jutland, Denmark, namely Stipilepas molerensis Carriol n. gen., n. sp., a scalpelliform gooseneck barnacle, and Plesiobrachylepas jutlandica Carriol n. gen., n. sp., a brachylepadomorph sessile form. This material...

Astronomically paced changes in deep-water circulation in the western North Atlantic during the middle Eocene

Science.gov (United States)

Vahlenkamp, Maximilian; Niezgodzki, Igor; De Vleeschouwer, David; Bickert, Torsten; Harper, Dustin; Kirtland Turner, Sandra; Lohmann, Gerrit; Sexton, Philip; Zachos, James; Pälike, Heiko

2018-02-01

North Atlantic Deep Water (NADW) currently redistributes heat and salt between Earth's ocean basins, and plays a vital role in the ocean-atmosphere CO2 exchange. Despite its crucial role in today's climate system, vigorous debate remains as to when deep-water formation in the North Atlantic started. Here, we present datasets from carbonate-rich middle Eocene sediments from the Newfoundland Ridge, revealing a unique archive of paleoceanographic change from the progressively cooling climate of the middle Eocene. Well-defined lithologic alternations between calcareous ooze and clay-rich intervals occur at the ∼41-kyr beat of axial obliquity. Hence, we identify obliquity as the driver of middle Eocene (43.5-46 Ma) Northern Component Water (NCW, the predecessor of modern NADW) variability. High-resolution benthic foraminiferal δ18O and δ13C suggest that obliquity minima correspond to cold, nutrient-depleted, western North Atlantic deep waters. We thus link stronger NCW formation with obliquity minima. In contrast, during obliquity maxima, Deep Western Boundary Currents were weaker and warmer, while abyssal nutrients were more abundant. These aspects reflect a more sluggish NCW formation. This obliquity-paced paleoceanographic regime is in excellent agreement with results from an Earth system model, in which obliquity minima configurations enhance NCW formation.

Virtual endocranial cast of earliest Eocene Diacodexis (Artiodactyla, Mammalia) and morphological diversity of early artiodactyl brains

Science.gov (United States)

Orliac, M. J.; Gilissen, E.

2012-01-01

The study of brain evolution, particularly that of the neocortex, is of primary interest because it directly relates to how behavioural variations arose both between and within mammalian groups. Artiodactyla is one of the most diverse mammalian clades. However, the first 10 Myr of their brain evolution has remained undocumented so far. Here, we used high-resolution X-ray computed tomography to investigate the endocranial cast of Diacodexis ilicis of earliest Eocene age. Its virtual reconstruction provides unprecedented access to both metric parameters and fine anatomy of the most complete endocast of the earliest artiodactyl. This picture is assessed in a broad comparative context by reconstructing endocasts of 14 other Early and Middle Eocene representatives of basal artiodactyls, allowing the tracking of the neocortical structure of artiodactyls back to its simplest pattern. We show that the earliest artiodactyls share a simple neocortical pattern, so far never observed in other ungulates, with an almond-shaped gyrus instead of parallel sulci as previously hypothesized. Our results demonstrate that artiodactyls experienced a tardy pulse of encephalization during the Late Neogene, well after the onset of cortical complexity increase. Comparisons with Eocene perissodactyls show that the latter reached a high level of cortical complexity earlier than the artiodactyls. PMID:22764165

Revised magnetic polarity time scale for the Paleocene and early Eocene and implications for Pacific plate motion

International Nuclear Information System (INIS)

Butler, R.F.; Coney, P.J.

1981-01-01

Magnetostratiographic studies of a continental sedimentary sequence in the Clark's Fork Basin, Wyoming and a marine sedimentary sequence at Gubbio, Italy indicate that the Paleocene--Eocene boundary occurs just stratigraphically above normal polarity zones correlative with magnetic anomaly 25 chron. These data indicate that the older boundary of anomaly 24 chron is 52.5 Ma. This age is younger than the late Paleocene age assigned by LaBrecque et al. [1977] and also younger than the basal Eocene age assigned by Ness et al. [1980]. A revised magnetic polarity time scale for the Paleocene and early Eocene is presented in this paper. Several changes in the relative motion system between the Pacific plate and neighboring plates occurred in the interval between anomaly 24 and anomaly 21. A major change in absolute motion of the Pacific plate is indicated by the bend in the Hawaiian--Emperor Seamount chain at approx.43 Ma. The revised magnetic polarity time scale indicates that the absolute motion change lags the relative motion changes by only approx.3--5 m.y. rather than by >10 m.y. as indicated by previous polarity time scales

New Cricetid Rodents from Strata near the Eocene-Oligocene Boundary in Erden Obo Section (Nei Mongol, China).

Science.gov (United States)

Li, Qian; Meng, Jin; Wang, Yuanqing

2016-01-01

New cricetids (Eucricetodon wangae sp. nov., Eucricetodon sp. and Pappocricetodon siziwangqiensis sp. nov.) are reported from the lower and middle parts of the "Upper Red" beds of the Erden Obo section in Nei Mongol, China. Eucricetodon wangae is more primitive than other known species of the genus from lower Oligocene of Asia and Europe in having a single anterocone on M1, a single connection between the protocone and the paracone, the anterior metalophule connection in M1-2 and weaker anteroconid and ectomesolophid in lower molars. Pappocricetodon siziwangqiensis is more advanced than other species of the genus in permanently missing P4 and having posterior protolophule connection. These fossils suggest that the age of the "Upper Red" of the Erden Obo section is younger than the age of the Upper Eocene Houldjin and Caijiachong formations, but older than those containing the Shandgolian faunas; the "Upper Red" is most closely correlative to the Ergilian beds in age, and probably close to the Eocene/Oligocene boundary. Given the age estimate, Eucricetodon wangae provides the new evidence to support that cricetid dispersal from Asia to Europe occurred prior to the Eocene-Oligocene boundary.

Extinction vs. Rapid Radiation: The Juxtaposed Evolutionary Histories of Coelotine Spiders Support the Eocene-Oligocene Orogenesis of the Tibetan Plateau.

Science.gov (United States)

Zhao, Zhe; Li, Shuqiang

2017-11-01

Evolutionary biology has long been concerned with how changing environments affect and drive the spatiotemporal development of organisms. Coelotine spiders (Agelenidae: Coelotinae) are common species in the temperate and subtropical areas of the Northern Hemisphere. Their long evolutionary history and the extremely imbalanced distribution of species richness suggest that Eurasian environments, especially since the Cenozoic, are the drivers of their diversification. We use phylogenetics, molecular dating, ancestral area reconstructions, diversity, and ecological niche analyses to investigate the spatiotemporal evolution of 286 coelotine species from throughout the region. Based on eight genes (6.5 kb) and 2323 de novo DNA sequences, analyses suggest an Eocene South China origin for them. Most extant, widespread species belong to the southern (SCG) or northern (NCG) clades. The origin of coelotine spiders appears to associate with either the Paleocene-Eocene Thermal Maximum or the hot period in early Eocene. Tibetan uplifting events influenced the current diversity patterns of coelotines. The origin of SCG lies outside of the Tibetan Plateau. Uplifting in the southeastern area of the plateau blocked dispersal since the Late Eocene. Continuous orogenesis appears to have created localized vicariant events, which drove rapid radiation in SCG. North-central Tibet is the likely location of origin for NCG and many lineages likely experienced extinction owing to uplifting since early Oligocene. Their evolutionary histories correspond with recent geological evidence that high-elevation orographical features existed in the Tibetan region as early as 40-35 Ma. Our discoveries may be the first empirical evidence that links the evolution of organisms to the Eocene-Oligocene uplifting of the Tibetan Plateau. [Tibet; biogeography; ecology; molecular clock; diversification.]. © The Author(s) 2017. Published by Oxford University Press, on behalf of the Society of Systematic

Upper Eocene Spherules at ODP Site 1090B

Science.gov (United States)

Liu, S.; Kyte, F. T.; Glass, B. P.; Gersonde, R.

2000-01-01

Our two labs independently discovered upper Eocene microtektites and microkrystites at ODP Site 1090, a new South Atlantic locality near the Agulhus Ridge. This is a significant new data point for the strewn fields of these spherules, which were recently extended into the Atlantic sector of the Southern Ocean when they were reported at ODP Site 689 on the Maude Rise. The microtektites have been regarded as related to North American tektites and the microkrystites as belonging to the clinopyroxene-bearing (cpx) spherule strewn field. Initial reports indicate that Site 1090 contains a complete sequence of upper Eocene sediments composed of diatom and nannofossil oozes. The magneto- and bio-stratigraphy indicate that impact-age sediments should occur in core 30X of Hole 1090B. One of us (FTK) took 2 cc samples at 10 cm intervals over 600 cm of core for Ir analyses and the senior author (SL) took 3 cc samples at 20 cm intervals to search for spherules. Both studies proved successful and additional samples were obtained to confirm initial results and better define the Ir anomaly and spherule abundances. Peak Ir concentrations of 0.97 ng/g were found at 1090B-30X-5, 105-106cm and 0.78 ng/g at 115-116 cm. Anomalous Ir concentrations (greater than 0.1 ng/g) extend over about 100 cm of core. Preliminary results indicate that the excess Ir at this site is about 25 ng per sq cm. About 380 microtektites (>63 pm) and 2492 microkrystites (>63 pm) were recovered over a 1.8 m interval with a peak abundance of microtektites (106/gram) and microkrystites (562/gram) at 1090B-30X- 5, 114-115 cm. The largest microtektite is approximately 960 x 1140 micron in size. About 55 % are spherical, and the rest are disc, cylinder, dumbbell, teardrop, or fragments. Most of the microtektites are transparent colorless, but a few are transparent pale brown or green. Preliminary data indicate that the microtektites at Site 1090 have similar major oxide compositions to those at Site 689. About 50% of

Taphonomy and abundance of birds from the Lower Eocene Fur Formation of Denmark

DEFF Research Database (Denmark)

Dyke, Gareth; Lindow, Bent Erik Kramer

2009-01-01

to quantify the shape of this radiation, but have largely been lacking. Here we report on a large collection of fossil birds from the Lower Eocene of Denmark (ca. 54 Ma) that includes three-dimensionally preserved, articulated specimens from carbonate concretions as well as skeletal imprints and feathers...

Green Transformational Leadership and Green Performance: The Mediation Effects of Green Mindfulness and Green Self-Efficacy

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Yu-Shan Chen

2014-09-01

Full Text Available No prior literature explores the influence of green transformational leadership on green performance, thus, this study develops a novel research framework to fill the research gap. This study investigates the influence of green transformational leadership on green performance and discusses the mediation effects of green mindfulness and green self-efficacy by means of structural equation modeling (SEM. The results indicate that green transformational leadership positively influences green mindfulness, green self-efficacy, and green performance. Moreover, this study demonstrates that the positive relationship between green transformational leadership and green performance is partially mediated by the two mediators: green mindfulness and green self-efficacy. It means that green transformational leadership can not only directly affect green performance positively but also indirectly affect it positively through green mindfulness and green self-efficacy. Therefore, firms need to raise their green transformational leadership, green mindfulness, and green self-efficacy to increase their green performance.

Green sturgeon distribution in the Pacific Ocean estimated from modeled oceanographic features and migration behavior.

Science.gov (United States)

Huff, David D; Lindley, Steven T; Wells, Brian K; Chai, Fei

2012-01-01

The green sturgeon (Acipenser medirostris), which is found in the eastern Pacific Ocean from Baja California to the Bering Sea, tends to be highly migratory, moving long distances among estuaries, spawning rivers, and distant coastal regions. Factors that determine the oceanic distribution of green sturgeon are unclear, but broad-scale physical conditions interacting with migration behavior may play an important role. We estimated the distribution of green sturgeon by modeling species-environment relationships using oceanographic and migration behavior covariates with maximum entropy modeling (MaxEnt) of species geographic distributions. The primary concentration of green sturgeon was estimated from approximately 41-51.5° N latitude in the coastal waters of Washington, Oregon, and Vancouver Island and in the vicinity of San Francisco and Monterey Bays from 36-37° N latitude. Unsuitably cold water temperatures in the far north and energetic efficiencies associated with prevailing water currents may provide the best explanation for the range-wide marine distribution of green sturgeon. Independent trawl records, fisheries observer records, and tagging studies corroborated our findings. However, our model also delineated patchily distributed habitat south of Monterey Bay, though there are few records of green sturgeon from this region. Green sturgeon are likely influenced by countervailing pressures governing their dispersal. They are behaviorally directed to revisit natal freshwater spawning rivers and persistent overwintering grounds in coastal marine habitats, yet they are likely physiologically bounded by abiotic and biotic environmental features. Impacts of human activities on green sturgeon or their habitat in coastal waters, such as bottom-disturbing trawl fisheries, may be minimized through marine spatial planning that makes use of high-quality species distribution information.

A synoptic review of the Eocene (Ypresian) cartilaginous fishes (Chondrichthyes: Holocephali, Elasmobranchii) of the Bolca Konservat-Lagerstätte, Italy

Science.gov (United States)

Marramà, Giuseppe; Carnevale, Giorgio; Engelbrecht, Andrea; Claeson, Kerin M.; Zorzin, Roberto; Fornasiero, Mariagabriella; Kriwet, Jürgen

2018-01-01

Here, we review and discuss the records and taxonomy of the Ypresian (Eocene) chondrichthyans from the famous Bolca Konservat-Lagerstätte in northeastern Italy. Despite the outstanding diversity and the numerous studies focusing on the actinopterygian faunas from Pesciara and Monte Postale, the current knowledge about the systematics, taxonomy and phylogenetic relationships of the cartilaginous fishes from these Eocene sites remains elusive and largely inadequate. The celebrated Eocene Bolca Lagerstätte has yielded several exquisitely preserved articulated remains of chondrichthyan fishes in which delicate structures and soft tissues are preserved, as well as isolated teeth. The cartilaginous fish assemblage of Bolca comprises at least 17 species-level taxa belonging to 10 families in 6 orders, including selachians (Carcharhiniformes, Lamniformes), batoids (Torpediniformes, Myliobatiformes, Rajiformes) and holocephalans (Chimaeriformes). The occurrence of holocephalans represented by an isolated fin-spine of the chimeroid Ischyodus in the Bolca assemblage is reported here for the first time and represents the first record of chimeroids in the Eocene of Italy and also southern Europe. The Bolca chondrichthyan assemblage is remarkably different from those of other contemporaneous Boreal or Tethyan deposits, suggesting that its taxonomic composition is largely influenced by the palaeoenvironmental context. However, this synoptic review also highlights the importance of detailed revisions of all chondrichthyan remains from the Bolca Konservat-Lagerstätten.

A New Eocene Casquehead Lizard (Reptilia, Corytophanidae from North America.

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Jack L Conrad

Full Text Available A new fossil showing affinities with extant Laemanctus offers the first clear evidence for a casquehead lizard (Corytophanidae from the Eocene of North America. Along with Geiseltaliellus from roughly coeval rocks in central Europe, the new find further documents the tropical fauna present during greenhouse conditions in the northern mid-latitudes approximately 50 million years ago (Ma. Modern Corytophanidae is a neotropical clade of iguanian lizards ranging from southern Mexico to northern South America.

Natural product terpenoids in Eocene and Miocene conifer fossils.

Science.gov (United States)

Otto, Angelika; White, James D; Simoneit, Bernd R T

2002-08-30

Numerous saturated and aromatic hydrocarbons, but not polar compounds, originating from plants and microorganisms (biomarkers) have been reported in sediments, coals, and petroleum. Here we describe natural product terpenoids found in two fossil conifers, Taxodium balticum (Eocene) and Glyptostrobus oregonensis (Miocene). A similar terpenoid pattern is also observed in extant Taxodium distichum. The preservation of characteristic terpenoids (unaltered natural products) in the fossil conifers supports their systematic assignment to the Cypress family (Cupressaceae sensu lato). The results also show that fossil conifers can contain polar terpenoids, which are valuable markers for (paleo)chemosystematics and phylogeny.

Paleoecological evaluation of Late Eocene biostratigraphic zonations of the Pacific Coast of North America

Science.gov (United States)

McDougall, Kristin

1980-01-01

The late Eocene zonal criteria of the west coast of North America are to a large extent controlled by paleoecology and, therefore, the correlation of coeval but environmentally different benthic foraminiferal faunas cannot be achieved before paleoecological control of the biostratigraphy is understood. The faunal trends, morphology, characteristic occurrences and estimated upper depth limits of the benthic foraminifers and associated microfossils in the Oregon and Washington study sections lead to the recognition of paleoecologic facies. The interpretation of these late Eocene facies as bathymetric and low-oxygen facies is based on analogous late Eocene and Holocene assemblages. The paleoecologic facies criteria are often identical to the stage and zonal criteria. In the California zonal schemes, the Narizian zones are identified by lower and middle bathyal faunas whereas the Refugian zones are identified by outer neritic and upper bathyal faunas. The Washington late Eocene zones are identified by middle bathyal and transported neritic faunas. Modifications of the existing zonal schemes such that time and not paleoecology is the controlling factor results in a zonation that synthesizes the existing zonal schemes, recognizes regional stratigraphic ranges of diagnostic species, and removes paleoecologically controlled species occurrences. The late Narizian encompasses a bathyal and a neritic facies. The bathyal facies is correlative with a modified Bulimina corrugata Zone of California and the Uvigerina cf. U. yazooensis Zone of Washington. The neritic late Narizian facies corresponds to a modified Bulimina schencki-Plectofrondicularia cf. P. jenkinsi Zone of Washington and a modified Amphimorphina jenkinsi Zone of California. The Refugian can also be divided into a neritic and a bathyal facies. Although the early and late subdivisions of this stage are tentative, the early Refugian is equivalent to the modified versions of the Cibicides haydoni and the Uvigerina

Eoalosa janvieri gen. et sp. nov., a new clupeid fish (Teleostei, Clupeiformes) from the Eocene of Monte Bolca, Italy.

Science.gov (United States)

Marramà, Giuseppe; Carnevale, Giorgio

2018-01-01

Fishes of the family Clupeidae are extremely abundant in the Eocene fossiliferous limestone of Monte Bolca representing the most common group from this celebrated locality. A new clupeid from the Pesciara site, Eoalosa janvieri gen. et sp. nov., is described. The new taxon exhibits a unique combination of characters supporting its recognition as a new genus and species of clupeid fish that is tentatively placed in the subfamily Alosinae. The description of this new taxon improves our knowledge of the diversity of clupeoid fishes in the Eocene of Monte Bolca.

Palaeoceanographic and biotic response during early Eocene extreme global warming events. Geologica Ultraiectina (328)

NARCIS (Netherlands)

Stap, H.L.

2010-01-01

Studying past intervals of abrupt global warming and massive carbon release can improve our knowledge in ways relevant to understanding future climate change. Possible paleo-analogues for future climate change are the early Paleogene hyperthermal events, such as the Paleocene-Eocene Thermal Maximum

Eocene tectonic compression in Northern Zealandia: Magneto-biostratigraphic constraints from the sedimentary records of New Caledonia (Southwest Pacific Ocean)

Science.gov (United States)

Dallanave, E.; Agnini, C.; Pascher, K. M.; Maurizot, P.; Bachtadse, V.; Hollis, C. J.; Dickens, G. R.; Collot, J.; Sevin, B.; Strogen, D.; Monesi, E.

2017-12-01

Published seismic profiles acquired from the Tasman Sea and northern Zealandia area (southwest Pacific) point to a widespread Eocene convergent deformation of oceanic and continental crust, with reverse faults and uplift (Tectonic Event of the Cenozoic in the Tasman Area; TECTA). The TECTA is interpreted as the precursor of the Tonga-Kermadec subduction initiation. Grande Terre is the main island of the New Caledonia archipelago and the largest emergent portion of northern Norfolk Ridge (part of northern Zealandia). Eocene sedimentary records exposed in Grande Terre contain a transition from pelagic micrite to terrigenous-rich calciturbidites, marking a shift from passive margin to convergent tectonic regime. This could represent the local expression of the convergence inception observed on a regional scale. We conducted an integrated magneto-biostratigraphic study, based on calcareous nannofossil and radiolaria, of two early-middle Eocene records cropping out near Noumea (southwest Grande Terre) and Koumac (northwest Grande Terre). The natural remanent magnetization of the sediments is complicated by multiple vector components, likely related to the late Eocene obduction, but a characteristic remanent magnetization has been successfully isolated. Overall the record spans from magnetic polarity Chron C23n to C18n, i.e. from 51 to 39 Ma. In this robust magnetic polarity-based chronological frame, the pelagic micrite to terrigenous-rich calciturbidites occurred near the top of Chron C21n and is dated 46 Ma. Furthermore, the magnetic mineral assemblage within part of the calciturbidites consists of hematite associated with maghemite. This association indicates emergent land as source of the terrigenous, suggesting a considerable uplift. Because 94% of the Zealandia continent is submerged, ocean drilling is needed to gauge the full extent and timing of Eocene compressive deformation revealed by the seismic profiles acquired in the Tasman area. This is a primary aim of

A new raninid crab, Pseudorogueus Rangiferus (Decapoda, Crustacea, from the Eocene of Spain

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Fraaye, R. H.B.

1995-04-01

Full Text Available new genus and species of raninid crab, Pseudorogueus rangiferus, is described from the Lower Eocene of Catalunya, Spanish Pyrenees.Se describe un nuevo género y especie de cangrejo Raninidae, Pseudorogueus rangiferus, proveniente del Eoceno inferior de los Pirineos Catalanes (Cataluña, España.

Low palaeoelevation of the northern Lhasa terrane during late Eocene: Fossil foraminifera and stable isotope evidence from the Gerze Basin.

Science.gov (United States)

Wei, Yi; Zhang, Kexin; Garzione, Carmala N; Xu, Yadong; Song, Bowen; Ji, Junliang

2016-06-08

The Lhasa terrane is a key region for understanding the paleoelevation of the southern Tibetan Plateau after India-Asia collision. The Gerze Basin, located in the northern part of the Lhasa terrane, is a shortening-related basin. We discovered Lagena laevis (Bandy) fossils in upper Eocene strata of the Gerze Basin. This type of foraminifera is associated with lagoon and estuarine environments, indicating that the northern part of the Lhasa terrane was near sea level during the late Eocene. We speculate that these foraminifera were transported inland by storm surges to low elevation freshwater lakes during times of marine transgressions. This inference is consistent with the relatively positive δ(18)O values in carbonate from the same deposits that indicate low palaeoelevations close to sea level. Considering the palaeoelevation results from the nearby Oligocene basins at a similar latitude and the volcanic history of the Lhasa terrane, we infer that large-magnitude surface uplift of the northern Lhasa terrane occurred between late Eocene and late Oligocene time.

Wet tropical climate in SE Tibet during the Late Eocene.

Science.gov (United States)

Sorrel, Philippe; Eymard, Ines; Leloup, Philippe-Herve; Maheo, Gweltaz; Olivier, Nicolas; Sterb, Mary; Gourbet, Loraine; Wang, Guocan; Jing, Wu; Lu, Haijian; Li, Haibing; Yadong, Xu; Zhang, Kexin; Cao, Kai; Chevalier, Marie-Luce; Replumaz, Anne

2017-08-10

Cenozoic climate cooling at the advent of the Eocene-Oligocene transition (EOT), ~33.7 Ma ago, was stamped in the ocean by a series of climatic events albeit the impact of this global climatic transition on terrestrial environments is still fragmentary. Yet archival constraints on Late Eocene atmospheric circulation are scarce in (tropical) monsoonal Asia, and the paucity of terrestrial records hampers a meaningful comparison of the long-term climatic trends between oceanic and continental realms. Here we report new sedimentological data from the Jianchuan basin (SE Tibet) arguing for wetter climatic conditions in monsoonal Asia at ~35.5 Ma almost coevally to the aridification recognized northwards in the Xining basin. We show that the occurrence of flash-flood events in semi-arid to sub-humid palustrine-sublacustrine settings preceded the development of coal-bearing deposits in swampy-like environments, thus paving the way to a more humid climate in SE Tibet ahead from the EOT. We suggest that this moisture redistribution possibly reflects more northern and intensified ITCZ-induced tropical rainfall in monsoonal Asia around 35.5 Ma, in accordance with recent sea-surface temperature reconstructions from equatorial oceanic records. Our findings thus highlight an important period of climatic upheaval in terrestrial Asian environments ~2-4 millions years prior to the EOT.

Beijing Star River: An Elegant-Distinguished Pet Stone(International Marketing Masters Make Marketings for Beijing Star River)

Institute of Scientific and Technical Information of China (English)

Sun Yongjian

2005-01-01

@@ Star River(or Star Bay), an elite works of Hong Yu Group, is located in Sijixinghe Road, Chaoyang Beilu,Beijing. It is a distinguished residence area, occupying land of 300 thousand sq. Meters. The north side is a forest garden with 1600 or more mu, the eastern side is a green belt with 2000-more mu.

Sedimentology and stratigraphy of the middle Eocene Guara carbonate platform near Arguis, South-West Pyrenean foreland: Implications for basin physiography

Science.gov (United States)

Huyghe, D.; Castelltort, S.; Serra-Kiel, J.; Filleaudeau, P.-Y.; Emmanuel, L.; Mouthereau, F.; Renard, M.

2009-04-01

The Pyrenees results from the collision between Spain and Europe and developed between the upper Cretaceous (Santonian) and the Miocene. Its foreland basins are characterised by a thick fill of detrital and carbonate sediments. The diversity of Eocene deposits in the southern Pyrenean foreland basin is of particular use in facies sedimentology due to their exceptional outcropping quality and well established stratigraphic framework and has been taken as type examples of many different sedimentary environments. Most studies have concerned facies sedimentology of detrital series in turbiditic environments, meandering and braided rivers, alluvial fans, and deltas. In contrast, the Eocene carbonate series have attracted less attention. The marine Guara limestones are a formation of lower to middle Eocene age deposited on the southern border of the western Pyrenean foreland basin (Jaca basin). They were deposited as a retrogradational carbonate platform dominated by large benthic foraminifers near or at the flexural forebulge of the foreland basin as the Pyrenean orogen developed. This formation represents the last episode of carbonate platform in the Pyrenees and remains poorly studied. In the present work our aim is to provide a detailed facies analysis and physiographic reconstructions of the Guara carbonate platform. This is crucial to unravel the respective influences of tectonics, climate and rheology of the lithosphere on the foreland basin tectonic and stratigraphic development, and it brings new constraints on the paleoenvironments and paleogeography during the Lutetian, i.e. at the beginning of the major phase of activity of the Pyrenean orogenesis. Two outcrops were studied in the Sierras Marginales at the localities of Arguis and Lusera. The Lusera section once restored in its initial position is located to the North of the Arguis section in a basinward direction such that comparing time-equivalent facies between these two sections helps us reconstructing

Eocene to Oligocene benthic foraminiferal isotopic record in the Bay of Biscay

International Nuclear Information System (INIS)

Miller, K.G.; Curry, W.B.

1982-01-01

Oxygen and carbon isotopic records of Eocene to Oligocene benthic foraminifera from two Bay of Biscay Deep Sea Drilling Project sites are presented. The delta 18 O figures for benthic foraminifera are significantly higher than those previously reported from deeper North Atlantic sites, the differences arising it is believed from diagenetic alteration of the sediments in the deeper-buried sites. (U.K.)

A large mimotonid from the middle Eocene of China sheds light on the evolution of lagomorphs and their kin.

Science.gov (United States)

Fostowicz-Frelik, Łucja; Li, Chuankui; Mao, Fangyuan; Meng, Jin; Wang, Yuanqing

2015-03-30

Mimotonids share their closest affinity with lagomorphs and were a rare and endemic faunal element of Paleogene mammal assemblages of central Asia. Here we describe a new species, Mimolagus aurorae from the Middle Eocene of Nei Mongol (China). This species belongs to one of the most enigmatic genera of fossil Glires, previously known only from the type and only specimen from the early Oligocene of Gansu (China). Our finding extends the earliest occurrence of the genus by at least 10 million years in the Paleogene of Asia, which closes the gap between Mimolagus and other mimotonids that are known thus far from middle Eocene or older deposits. The new species is one of the largest known pre-Oligocene Glires. As regards duplicidentates, Mimolagus is comparable with the largest Neogene continental leporids, namely hares of the genus Lepus. Our results suggest that ecomorphology of this species was convergent on that of small perissodactyls that dominated faunas of the Mongolian Plateau in the Eocene, and probably a result of competitive pressure from other Glires, including a co-occurring mimotonid, Gomphos.

A Possible Late Paleocene-Early Eocene Ocean Acidification Event Recoded in the Adriatic Carbonate Platform

Science.gov (United States)

Weiss, A.; Martindale, R. C.; Kosir, A.; Oefinger, J.

2017-12-01

The Paleocene-Eocene Thermal Maximum (PETM) event ( 56.3 Ma) was a period of massive carbon release into the Earth system, resulting in significant shifts in ocean chemistry. It has been proposed that ocean acidification - a decrease in the pH and carbonate saturation state of the water as a result of dissolved carbon dioxide in sea water - occurred in both the shallow and deep marine realms. Ocean acidification would have had a devastating impact on the benthic ecosystem, and has been proposed as the cause of decreased carbonate deposition in marine sections and coral reef collapse during the late Paleocene. To date, however, the only physical evidence of Paleocene-Eocene ocean acidification has been shown for offshore sites (i.e., a shallow carbonate compensation depth), but isotope analysis (i.e. B, I/Ca) suggests that acidification occurred in the shallow shelves as well. Several sites in the Kras region of Slovenia, has been found to contain apparent erosion surfaces coeval with the Paleocene-Eocene Boundary. We have investigated these potentially acidified horizons using petrography, stable carbon isotopes, cathodoluminescence, and elemental mapping. These datasets will inform whether the horizons formed by seafloor dissolution in an acidified ocean, or are due to subaerial exposure, or burial diagenesis (i.e. stylotization). Physical erosion and diagenesis can easily be ruled out based on field relationships and petrography, but the other potential causes must be analyzed more critically.

A dynamic climate and ecosystem state during the Paleocene-Eocene Thermal Maximum: inferences from dinoflagellate cyst assemblages on the New Jersey Shelf

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A. Sluijs

2009-08-01

Full Text Available Late Paleocene and Early Eocene climates and ecosystems underwent significant change during several transient global warming phases, associated with rapidly increasing atmospheric carbon concentrations, of which the Paleocene-Eocene Thermal Maximum (PETM; ~55.5 Ma is best studied. While biotic response to the PETM as a whole (~170 kyrs has been relatively well documented, variations during the PETM have been neglected. Here we present organic dinoflagellate cyst (dinocyst distribution patterns across two stratigraphically expanded PETM sections from the New Jersey Shelf, Bass River and Wilson Lake. Many previously studied sites show a uniform abundance of the thermophilic and presumably heterotrophic taxon Apectodinium that spans the entire carbon isotope excursion (CIE of the PETM. In contrast, the New Jersey sections show large variations in abundances of many taxa during the PETM, including the new species Florentinia reichartii that we formally propose. We infer paleoecological preferences of taxa that show temporal abundance peaks, both qualitative and absolute quantitative, from empirical as well as statistical information, i.e., principle (PCA and canonical correspondence analyses (CCA. In the CCAs, we combine the dinocyst data with previously published environmental proxy data from these locations, such as TEX₈₆ paleothermometry, magnetic susceptibility and sedimentary size fraction. The combined information supports previous inferences that sea level rose during the PETM, but also indicates a (regional increase in fresh-water runoff that started ~10 kyr after the onset of the CIE, and perhaps precession-paced cycles in sea surface productivity. The highly variable dinocyst assemblages of the PETM contrast with rather stable Upper Paleocene assemblages, which suggests that carbon input caused a dynamic climate state, at least regionally.

A late Eocene palynological record of climate change and Tibetan Plateau uplift (Xining Basin, China)

NARCIS (Netherlands)

Hoorn, C.; Straathof, J.; Abels, H.A.; Xu, Y.; Utescher, T.; Dupont-Nivet, G.

2012-01-01

Climate models suggest that Asian paleoenvironments, monsoons and continental aridification were primarily governed by tectonic uplift and sea retreat since the Eocene with potential contribution of global climate changes. However, the cause and timing of these paleoenvironmental changes remain

Earth Pressure at rest of Søvind Marl – a highly overconsolidated Eocene clay

DEFF Research Database (Denmark)

Grønbech, Gitte Lyng; Ibsen, Lars Bo; Nielsen, Benjaminn Nordahl

2016-01-01

The present study evaluated earth pressure at rest, K0, in highly overconsolidated Eocene clay called Søvind Marl, which exhibits extremely high plasticity indices of up to 300%, a highly fissured structure, and preconsolidation stresses up to 6,800 kPa. Continuous Loading Oedometer (CLO) tests...

The use of hydroxyacids as geochemical indicators

Science.gov (United States)

Cardoso, J. N.; Eglinton, G.

1983-04-01

The distributions of hydroxyacids in a variety of recent and ancient sediments have been determined by gas chromatography-mass spectrometry. A lacustrine sediment (Rostherne Mere, U.K.) and two marine situations (Cariaco Trench, Black Sea) were analyzed as examples of recent depositional environments. Beta-hydroxyacids occurred in all of the recent sediments, consistent with their presumed microbial origin, whereas di- and trihydroxyacids were present in the sediments with a significant higher plant input (Black Sea and Rostherne Mere sediments). The two ancient (Eocene) sediments examined, viz, the Greene River (U.S.) and Messel (Germany) oil shales, contained only trace amounts of hydroxyacids. These results provide evidence that hydroxyacids are in general not well preserved over geological time.

Gigantism in unique biogenic magnetite at the Paleocene-Eocene Thermal Maximum

OpenAIRE

Schumann, Dirk; Raub, Timothy D.; Kopp, Robert E.; Guerquin-Kern, Jean-Luc; Wu, Ting-Di; Rouiller, Isabelle; Smirnov, Aleksey V.; Sears, S. Kelly; Lücken, Uwe; Tikoo, Sonia M.; Hesse, Reinhard; Kirschvink, Joseph L.; Vali, Hojatollah

2008-01-01

We report the discovery of exceptionally large biogenic magnetite crystals in clay-rich sediments spanning the Paleocene-Eocene Thermal Maximum (PETM) in a borehole at Ancora, New Jersey. Aside from previously-described abundant bacterial magnetofossils, electron microscopy reveals novel spearhead-like and spindle-like magnetite up to 4 μm long and hexaoctahedral prisms up to 1.4 μm long. Similar to magnetite produced by magnetotactic bacteria, these single-crystal particles exhibit chemical...

Description of a Well Preserved Fetus of the European Eocene Equoid Eurohippus messelensis.

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Jens Lorenz Franzen

Full Text Available The early Middle Eocene locality of Grube Messel, near Darmstadt (Germany, is famous for its complete vertebrate skeletons. The degree of preservation of soft tissues, such as body silhouettes, internal organs and gut contents, is frequently remarkable. The present specimen was analyzed for remnants of the reproductive system. Classic anatomy and osteology and high-resolution micro-x-ray were applied to describe the fetus of the European Eocene equoid Eurohippus messelensis. Scanning electronic microscopy (SEM was used for determination of soft tissue remnants. The fetus is the earliest and best-preserved fossil specimen of its kind. The postcranial fetal skeleton is almost complete and largely articulated, allowing the conclusion that the pregnant mare was in late gestation. The apparent intrauterine position of the fetus is normal for the phase of pregnancy. Death of mare and fetus were probably not related to problems associated with parturition. Soft tissue interpreted as the uteroplacenta and a broad uterine ligament are preserved due to bacterial activity and allow considerations on the evolutionary development of the structures.

Description of a Well Preserved Fetus of the European Eocene Equoid Eurohippus messelensis.

Science.gov (United States)

Franzen, Jens Lorenz; Aurich, Christine; Habersetzer, Jörg

2015-01-01

The early Middle Eocene locality of Grube Messel, near Darmstadt (Germany), is famous for its complete vertebrate skeletons. The degree of preservation of soft tissues, such as body silhouettes, internal organs and gut contents, is frequently remarkable. The present specimen was analyzed for remnants of the reproductive system. Classic anatomy and osteology and high-resolution micro-x-ray were applied to describe the fetus of the European Eocene equoid Eurohippus messelensis. Scanning electronic microscopy (SEM) was used for determination of soft tissue remnants. The fetus is the earliest and best-preserved fossil specimen of its kind. The postcranial fetal skeleton is almost complete and largely articulated, allowing the conclusion that the pregnant mare was in late gestation. The apparent intrauterine position of the fetus is normal for the phase of pregnancy. Death of mare and fetus were probably not related to problems associated with parturition. Soft tissue interpreted as the uteroplacenta and a broad uterine ligament are preserved due to bacterial activity and allow considerations on the evolutionary development of the structures.

Beijing Star River: An Elegant-Distinguished Pet Stone(International Marketing Masters Make Marketings for Beijing Star River)

Institute of Scientific and Technical Information of China (English)

Sun; Yongjian

2005-01-01

　　Star River(or Star Bay), an elite works of Hong Yu Group, is located in Sijixinghe Road, Chaoyang Beilu,Beijing. It is a distinguished residence area, occupying land of 300 thousand sq. Meters. The north side is a forest garden with 1600 or more mu, the eastern side is a green belt with 2000-more mu.……

A newly isolated Haloalkaliphilic bacterium from middle-late Eocene halite formed in salt lakes in China

Czech Academy of Sciences Publication Activity Database

Meng, F. W.; Wang, X.-Q.; Ni, P.; Kletetschka, Günther; Li, Y-P.; Yang, Ch.-H.

2015-01-01

Roč. 30, č. 3 (2015), s. 321-330 ISSN 0891-2556 Institutional support: RVO:67985831 Keywords : ancient microorganism * primary fluid inclusion * halite * Eocene Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.440, year: 2015

Fractionation of rare earth elements in the Mississippi River estuary and river sediments

Science.gov (United States)

Adebayo, S. B.; Johannesson, K. H.

2017-12-01

This study presents the first set of data on the fractionation of rare earth elements (REE) in the mixing zone between the Mississippi River and the Gulf of Mexico, as well as the fractionation of REE in the operationally defined fractions of Mississippi River sediments. This subject is particularly important because the Mississippi river is one of the world's major rivers, and contributes a substantial amount of water and sediment to the ocean. Hence, it is a major source of trace elements to the oceans. The geochemistry of the REE in natural systems is principally important because of their unique chemical properties, which prompt their application as tracers of mass transportation in modern and paleo-ocean environments. Another important consideration is the growth in the demand and utilization of REE in the green energy and technology industries, which has the potential to bring about a change in the background levels of these trace elements in the environment. The results of this study show a heavy REE enrichment of both the Mississippi River water and the more saline waters of the mixing zone. Our data demonstrate that coagulation and removal of REE in the low salinity region of the estuary is more pronounced among the Light REE ( 35% for Nd) compared to the Heavy REE. Remarkably, our data also indicate that REE removal in the Mississippi River estuary is significantly less than that observed in other estuaries, including the Amazon River system. We propose that the high pH/alkalinity of the Mississippi River is responsible for the greater stability of REE in the Mississippi River estuary. The results of sequential extraction of river sediments reveal different Sm/Nd ratios for the various fractions, which we submit implies different 143Nd/144Nd ratios of the labile fractions of the sediments. The possible impact of such hypothesized different Nd isotope signatures of labile fractions of the river sediments on Gulf of Mexico seawater is under investigation.

Normal polarity magnetosubchrons in 24r and the age of the Paleocene-Eocene boundary

Energy Technology Data Exchange (ETDEWEB)

Lerbekmo, J.F.; Heaman, L.M.; Baadsgaard, H.; Muehlenbachs, K.; Evans, M.E.; Sweet, A.R. [University of Alberta, Edmonton, AB (Canada)

2008-07-15

A late Paleocene to early Eocene sequence of flat-lying continental strata occurs in an area known as Obed Mountain, west-central Alberta. The upper 110 m consist of interbedded fluvial channel sandstones and overbank mudrocks containing five back swamp coal seams. Two coreholes, 3.5 km apart, that extend through the entire coal zone were sampled for magnetostratigraphy and {sup 13}C isotope analysis. Bentonites in the No. 1 (lowest) and No. 5 coal seams and a tuff in the No. 3 coal seam were sampled for U-Pb and (or) Rb-Sr dating of zircon and biotite, respectively. Magnetostratigraphic analysis of 520 samples identified the younger part of chron 25r, the whole of chron 25n and the older half of chron 24r. We find six normal polarity subzones in this part of chron 24r, which we correlate to tiny wiggles 6 to 11 in marine magnetic profiles. Carbon isotope analysis of 14 samples from two cores revealed a negative shift of about 2 parts per thousand peaking near the base of 24r.8r. We interpret this as the carbon isotope excursion (CIE), the base of which is now accepted as defining the Paleocene-Eocene boundary. The thickness of the CIE in the Obed Mountain section implies that it lasted between 210 000 and 254 000 years. Radiometric dates of 58.4 {+-} 0.2, 57.7 {+-} 0.3, and 56.9 {+-} 0.8 Ma are obtained for the No. 1, No. 3, and No. 5 coals, respectively. Combining these with magnetostratigraphy and cyclostratigraphy yields an age of 57.1 {+-} 0.1 Ma for the Paleocene-Eocene boundary.

Fuenferrada 3, the first Eocene mammal locality in the depression of Montalbán (Teruel, Spain), with some remarks on the fauna of Olalla 4A

NARCIS (Netherlands)

Freudenthal, M.

1997-01-01

The rodent fauna of Fuenferrada contains two species of Theridomyidae and three species of Gliridae. It is compared with the Early Oligocene fauna of Olalla 4A, and with the Late Eocene fauna of Aguatón 2D. The absence of Cricetidae serves to determine its age as latest Eocene.

Green Transformational Leadership and Green Performance: The Mediation Effects of Green Mindfulness and Green Self-Efficacy

OpenAIRE

Yu-Shan Chen; Ching-Hsun Chang; Yu-Hsien Lin

2014-01-01

No prior literature explores the influence of green transformational leadership on green performance, thus, this study develops a novel research framework to fill the research gap. This study investigates the influence of green transformational leadership on green performance and discusses the mediation effects of green mindfulness and green self-efficacy by means of structural equation modeling (SEM). The results indicate that green transformational leadership positively influences green min...

A review of the platanaceous woods from the Eocene paratropical rainforest of south-east England

NARCIS (Netherlands)

Poole, I.J.; Davies, Kevin L.; Wilkinson, Hazel P.

2002-01-01

Small diameter pyritized axes, commonly referred to as ‘twigs’, of fossil platanaceous wood are described from the Lower Eocene London Clay Formation of south-east England. These twigs are characterized by solitary vessels with scalariform perforation plates, opposite intervessel pits, and tall,

Earth system feedback statistically extracted from the Indian Ocean deep-sea sediments recording Eocene hyperthermals.

Science.gov (United States)

Yasukawa, Kazutaka; Nakamura, Kentaro; Fujinaga, Koichiro; Ikehara, Minoru; Kato, Yasuhiro

2017-09-12

Multiple transient global warming events occurred during the early Palaeogene. Although these events, called hyperthermals, have been reported from around the globe, geologic records for the Indian Ocean are limited. In addition, the recovery processes from relatively modest hyperthermals are less constrained than those from the severest and well-studied hothouse called the Palaeocene-Eocene Thermal Maximum. In this study, we constructed a new and high-resolution geochemical dataset of deep-sea sediments clearly recording multiple Eocene hyperthermals in the Indian Ocean. We then statistically analysed the high-dimensional data matrix and extracted independent components corresponding to the biogeochemical responses to the hyperthermals. The productivity feedback commonly controls and efficiently sequesters the excess carbon in the recovery phases of the hyperthermals via an enhanced biological pump, regardless of the magnitude of the events. Meanwhile, this negative feedback is independent of nannoplankton assemblage changes generally recognised in relatively large environmental perturbations.

Diversity of Scydmaeninae (Coleoptera: Staphylinidae) in Upper Eocene Rovno amber.

Science.gov (United States)

Jałoszyński, Paweł; Perkovsky, Evgeny

2016-08-25

Among nearly 1270 inclusions of Coleoptera found in Upper Eocene Rovno amber, 69 were identified as ant-like stone beetles (Scydmaeninae); 34 were possible to unambiguously determine to the tribal level and were studied in detail. Rovnoleptochromus ableptonoides gen. & sp. n. (Mastigitae: Clidicini), Vertheia quadrisetosa gen. & sp. n. (Cephenniitae: Eutheiini), Cephennomicrus giganteus sp. n. (Cephenniitae: Cephenniini), Glaesoconnus unicus gen. & sp. n. (Scydmaenitae: Glandulariini), Rovnoscydmus frontalis gen. & sp. n. (Scydmaenitae: Glandulariini; type species of Rovnoscydmus), Rovnoscydmus microscopicus sp. n., Euconnus (incertae sedis, near Cladoconnus) palaeogenus sp. n. (Scydmaenitae: Glandulariini), and Stenichnus (s. str.) proavus sp. n. (Scydmaenitae: Glandulariini) are described. Additionally, specimens representing one undescribed species of Vertheia, one of Cephennodes, five of Cephennomicrus, one of Euconnus, one of Microscydmus are recorded, and nine specimens representing an unknown number of species of Rovnoscydmus (and two putative Rovnoscydmus), one Euconnus (and one putative Euconnus), two putative Microscydmus and one putative Scydmoraphes were found in the studied material. The composition of Scydmaeninae fauna in Rovno amber is discussed in the context of ecological preferences and distribution of extant taxa. It is concluded that subtropical and tropical taxa were present in the region where Rovno amber has formed, most notably the second genus and species of the extant tribe Clidicini known from the Eocene of Europe, and six species of the extant genus Cephennomicrus, for the first time found in the fossil record. An annotated catalog of nominal species of Scydmaeninae known in the fossil record is given.

How many upper Eocene microspherule layers: More than we thought

Science.gov (United States)

Hazel, Joseph E.

1988-01-01

The scientific controversy over the origin of upper Eocene tektites, microtektites and other microspherules cannot be logically resolved until it is determined just how many events are involved. The microspherule-bearing beds in marine sediments have been dated using standard biozonal techniques. Although a powerful stratigraphic tool, zonal biostratigraph has its limitations. One is that if an event, such as a microspherule occurrence, is observed to occur in a zone at one locality and then a similar event observed in the same zone at another locality, it still may be unwarranted to conclude that these events exactly correlate. To be in a zone a sample only need be between the fossil events that define the zone boundaries. It is often very difficult to accurately determine where within a zone one might be. Further, the zone defining events do not everywhere occur at the same points in time. That is, the ranges of the defining taxa are not always filled. Thus, the length of time represented by a zone (but not, of course, its chronozone) can vary from place to place. These problems can be offset by use of chronostratigraphic modelling techniques such as Graphic Correlation. This technique was used to build a Cretaceous and Cenozoic model containing fossil, magnetopolarity, and other events. The scale of the model can be demonstrated to be linear with time. This model was used to determine the chronostratigraphic position of upper Eocene microspherule layers.

Eocene Podocarpium (Leguminosae) from South China and its biogeographic implications.

Science.gov (United States)

Xu, Qingqing; Qiu, Jue; Zhou, Zhekun; Jin, Jianhua

2015-01-01

Podocarpium A. Braun ex Stizenberger is one of the most common legumes in the Neogene of Eurasia, including fossil fruits, seeds, leaves, and possible flower and pollen grains. This genus is not completely consistent with any extant genera according to gross morphological characters and poorly preserved cuticular structures reported in previous studies. The fossil pods collected from the coal-bearing series of the Changchang Basin of Hainan Island and Maoming Basin of Guangdong, South China, are examined by morphologically comparative work, with special reference to venation patterns and placental position. These distinctive features, as well as the ovule development of pods from different developmental stages and the epidermal structure of the pods, as distinguished from previous records lead to the conclusion that these fossils can be recognized as a new species of Podocarpium, P. eocenicum sp. nov. This new discovery indicates that Podocarpium had arrived in South China by the Eocene. Investigation on the fossil records of this extinct genus shows that P. eocenicum is the earliest and lowest latitude fossil data. The possible occurrence pattern of this genus is revealed as follows: Podocarpium had distributed in the South China at least in the middle Eocene, and then migrated to Europe during the Oligocene; in the Miocene this genus reached its peak in Eurasia, spreading extensively across subtropical areas to warm temperate areas; finally, Podocarpium shrank rapidly and became extinct in Eurasia during the Pliocene.

Terrestrial and lacustrine gastropods from the Priabonian (upper Eocene) of the Sultanate of Oman.

Science.gov (United States)

Harzhauser, Mathias; Neubauer, Thomas A; Kadolsky, Dietrich; Pickford, Martin; Nordsieck, Hartmut

2016-01-01

Terrestrial and aquatic gastropods from the upper Eocene (Priabonian) Zalumah Formation in the Salalah region of the Sultanate of Oman are described. The assemblages reflect the composition of the continental mollusc fauna of the Palaeogene of Arabia, which, at that time, formed parts of the southeastern Tethys coast. Several similarities with European faunas are observed at the family level, but are rarer at the genus level. These similarities point to an Eocene (Priabonian) rather than to a Rupelian age, although the latter correlation cannot be entirely excluded. At the species level, the Omani assemblages lack any relations to coeval faunas. This suggests the possible presence of a distinct biogeographic province during the Palaeogene or may simply reflect the extremely sparse non-marine fossil record of the Eocene in the Tethys region. The occurrence of the genera Lanistes, Pila, and Gulella along with some pomatiids, probably related to extant genera, suggests that the modern African-Arabian continental faunas can be partly traced back to Eocene times and reflect very old autochthonous developments. In contrast, the diverse Vidaliellidae went extinct, and the morphologically comparable Neogene Achatinidae may have occupied the equivalent niches in extant environments. Carnevalea Harzhauser and Neubauer nov. gen., Arabiella Kadolsky, Harzhauser and Neubauer nov. gen., Pyrgulella Harzhauser, Kadolsky and Neubauer nov. gen., Salalahia Kadolsky, Harzhauser and Neubauer nov. gen., Omanitopsis Harzhauser and Neubauer nov. gen., Arabicolaria Harzhauser and Neubauer nov. gen., Pacaudiella Harzhauser and Neubauer nov. gen., Goniodomulus Harzhauser and Neubauer nov. gen., Eoquickia Harzhauser and Neubauer nov. gen., Omanillya H. Nordsieck nov. gen. and Omanifera H. Nordsieck nov. gen. are introduced as new genera. Pila neuberti Harzhauser and Neubauer nov. sp., Arabiella arabica Kadolsky, Harzhauser and Neubauer nov. sp., Pyrgulella parva Harzhauser, Kadolsky and

Short-term fluctuations in vegetation and phytoplankton during the Middle Eocene greenhouse climate: a 640-kyr record from the Messel oil shale (Germany)

Science.gov (United States)

Lenz, Olaf K.; Wilde, Volker; Riegel, Walter

2011-11-01

The Palaeogene was the most recent greenhouse period on Earth. Especially for the Late Palaeocene and Early Eocene, several superimposed short-term hyperthermal events have been described, including extremes such as the Palaeocene-Eocene Thermal Maximum. Major faunal and floral turnovers in the marine and terrestrial realms were recorded in association with these events. High-resolution palynological analysis of the early Middle Eocene maar lake sediments at Messel, near Darmstadt, Germany, provides an insight into the dynamics of a climax vegetation during the Middle Eocene greenhouse climate in a time span without significant climatic excursions. Numerical techniques like detrended correspondence analysis and wavelet analysis have been applied to recognize cyclic fluctuations and long-term trends in the vegetation through a time interval of approximately 640 kyr. Based on the numerical zoning of the pollen diagram, three phases in the development of the vegetation may be distinguished. Throughout these phases, the climax vegetation did not change substantially in qualitative composition, but a trend towards noticeably less humid conditions probably in combination with a drop of the water level in the lake may be recognized. A shift in algal population from the freshwater dinoflagellate cyst Messelodinium thielepfeifferae to a dominance of Botryococcus in the uppermost part of the core is interpreted as a response to changes in acidity and nutrient availability within the lake. Time series analyses of pollen assemblages show that variations in the Milankovitch range of eccentricity, obliquity and precession can be distinguished. In addition, fluctuations in the sub-Milankovitch range are indicated. This demonstrates that floral changes during steady depositional conditions in the Middle Eocene of Messel were controlled by orbital forcing.

GREEN PACKAGING, GREEN PRODUCT, GREEN ADVERTISING, PERSEPSI, DAN MINAT BELI KONSUMEN

Directory of Open Access Journals (Sweden)

Imam Santoso

2016-12-01

Full Text Available Environmental problems become one of the strategic issues in achieving global competitiveness. One of the issues is products that are made from environmental friendly materials or known as green product. Furthermore, in green products marketing, the company also uses green packaging and green advertising concept. This study aimed to analyze the effect of green packaging, green products, and green advertising on consumer perception and purchasing intention. The study was conducted in Ketawanggede Village, Lowokwaru Sub-district, Malang City. The sampling method used nonprobability accidential sampling techniques. The numbers of respondents were 113 consumers in study site. Data were collected by interview using questionnaires. The method of analysis used Generalized Structured Component Analysis (GSCA. The analysis showed that the green packaging, green products, and green advertising had positive significant influence on consumer perceptions. Meanwhile, green product and consumer perception had positive significant influence on purchasing interest, but the green packaging and green advertising has not found sufficient evidence in influencing purchasing intention.

Palaeocology of coal-bearing Eocene sediments in central Anatolia (Turkey) based on quantitative palynological data

Energy Technology Data Exchange (ETDEWEB)

Akkiraz, M.S.; Kayseri, M.S.; Akgun, F. [Dokuz Eylul University, Izmir (Turkey). Dept. of Geological Engineering

2008-04-15

In this study, the lignite-bearing Yoncali formation between Yozgat and Sorgun, in central Anatolia has been palynologically examined. Based on 37 outcrop samples, quantitative palynological studies recognized 64 genera and 136 palynoflora species in the palynological assemblage, which indicated a Middle-Late Eocene age. This paper also presents a quantitative palaeovegetation and palaeoclimate reconstruction for the Middle-Upper Eocene coal occurrences of Central Anatolia on the basis of palynomorph assemblages. The diversified floral and ecological characteristics of the pollen taxa indicates that the Middle-Upper Eocene formations in central Anatolia were characterized by the presence of a complex mangrove swamp with contributions by Nypa, Pelliciera, Avicennia, Diporites tszkaszentgydrgyi and dinoflagellate cysts which reflect warm climatic conditions. Lowland-riparian and montane elements are characterized by the dominance of Myricaceae, Symplocaceae, Icacinaceae, Quercus, Pinus and Castanea. Swamp-freshwater elements are represented by Sparganjaceae, Nymphaceae, Taxodjaceae, Cupressaceae and Nyssa as well as fern spores such as Osmundaceae and Gleicheniaceae. The calculations were performed with the help of the 'Coexistence Approach' method to climatically evaluate palynoflora from the Yozgat-Sorgun area. The obtained results have been compared to data derived from the application of the Coexistence Approach to other, already published Central Anatolian palynofloras of the same age. The results of the climatic inferences suggest that the palaeoclimatic conditions were in the megathermal zone, megatherm/mesotherm intermediate zone whereas mesothermic conditions prevailed in the montane region. Likewise, the results of mean annual range of temperatures indicate the influence of the Indian ocean, which enabled the development of the mangroves.

The use of green waste from tourist attractions for renewable energy production: The potential and policy implications

International Nuclear Information System (INIS)

Shi, Yan; Du, Yuanyuan; Yang, Guofu; Tang, Yuli; Fan, Likun; Zhang, Jun; Lu, Yijun; Ge, Ying; Chang, Jie

2013-01-01

Quantifying potential renewable energy sources from tourist attractions is a pivotal initial step in developing energy policies and strategies for low-carbon tourist industry development. Although solar energy and wind power have been in use for providing power for tourist attractions, the value of using waste biomass for energy production is still poorly understood. Here we advocate a promising approach that produces energy from green waste created by tourism attractions currently existing in large numbers and is still increasing dramatically. Using the Yangtze River Delta (YRD) of China as an example, we evaluated the potential of utilizing green waste to produce energy from 385 tourist attractions in 16 cities of this region. Our results showed that the total potential energy production using the green waste biomass was estimated at 6740 TJ/yr (1 TJ=10 12 J) with an average of 137 GJ/ha/yr (1 GJ=10 9 J), accounting for 6% (the average of the Yangtze River Delta, some scenic areas up to 93%) of YRD′s tourism industry′s energy consumption in 2008. The use of green waste for energy production is possible using current technology and could result in a win–win approach by reducing waste and increasing the renewable energy yields. -- Highlights: •Green waste from tourist attractions could help offset the tourist′s fossil fuel consumption. •Economic, technical, and social feasibility analysis of green waste for energy production. •Puts forward policy recommendations, from management regulations, public support etc

An exceptionally preserved Eocene shark and the rise of modern predator-prey interactions in the coral reef food web.

Science.gov (United States)

Fanti, Federico; Minelli, Daniela; Conte, Gabriele Larocca; Miyashita, Tetsuto

2016-01-01

Following extreme climatic warming events, Eocene Lagerstätten document aquatic and terrestrial vertebrate faunas surprisingly similar to modern counterparts. This transition in marine systems is best documented in the earliest teleost-dominated coral reef assemblage of Pesciara di Bolca, northern Italy, from near the end of the Eocene Climatic Optimum. Its rich fauna shows similarities with that of the modern Great Barrier Reef in niche exploitation by and morphological disparity among teleost primary consumers. However, such paleoecological understanding has not transcended trophic levels above primary consumers, particularly in carcharhiniform sharks. We report an exceptionally preserved fossil school shark (Galeorhinus cuvieri) from Pesciara di Bolca. In addition to the spectacular preservation of soft tissues, including brain, muscles, and claspers, this male juvenile shark has stomach contents clearly identifiable as a sphyraenid acanthomorph (barracuda). This association provides evidence that a predator-prey relationship between Galeorhinus and Sphyraena in the modern coral reefs has roots in the Eocene. A growth curve of the living species of Galeorhinus fitted to G. cuvieri suggests that all specimens of G. cuvieri from the lagoonal deposits of Bolca represent sexually and somatically immature juveniles. The modern trophic association between higher-degree consumers (Galeorhinus and Sphyraena) has a counterpart in the Eocene Bolca, just as Bolca and the Great Barrier Reef show parallels among teleost primary consumers. Given the age of Bolca, trophic networks among consumers observed in modern coral reefs arose by the exit from the Climatic Optimum. The biased representation of juveniles suggests that the Bolca Lagerstätte served as a nursery habitat for G. cuvieri. Ultraviolet photography may be useful in probing for exceptional soft tissue preservation before common acid preparation methods.

Identification of the Paleocene-Eocene boundary in coastal strata in the Otway Basin, Victoria, Australia

NARCIS (Netherlands)

Frieling, J.; Huurdeman, Emiel; Rem, Charlotte; Donders, T.H.; Pross, Jorg; Bohaty, Steven M.; Holdgate, Guy; Gallagher, Stephen; McGowran, Brian; Bijl, P.K.

2018-01-01

Detailed, stratigraphically well-constrained environmental reconstructions are available for Paleocene and Eocene strata at a range of sites in the southwest Pacific Ocean (New Zealand and East Tasman Plateau; ETP) and Integrated Ocean Discovery Program (IODP) Site U1356 in the south of the

A simple and portable colorimeter using a red-green-blue light-emitting diode and its application to the on-site determination of nitrite and iron in river-water.

Science.gov (United States)

Suzuki, Yasutada; Aruga, Terutomi; Kuwahara, Hiroyuki; Kitamura, Miki; Kuwabara, Tetsuo; Kawakubo, Susumu; Iwatsuki, Masaaki

2004-06-01

A portable colorimeter using a red-green-blue light-emitting diode as a light source has been developed. An embedded controller sequentially turns emitters on and off, and acquires the signals detected by two photo diodes synchronized with their blinking. The controller calculates the absorbance and displays it on a liquid-crystal display. The whole system, including a 006P dry cell, is contained in a 100 x 70 x 50 mm aluminum case and its mass is 280 g. This colorimeter was successfully applied to the on-site determination of nitrite and iron in river-water.

Characteristics of microfossils assemblages of core SB-01 from Sanshui basin and discussion of paleocene-eocene boundary

International Nuclear Information System (INIS)

Chen Liang; Xie Yecai; Wang Zhengqing; Ma Chuang

2011-01-01

Characteristics of microfossils assemblages of core SB-01 from Sanshui Basin have been analysised in this paper. Based on micropaleontological study and data from carbon and oxygen isotopes of bulk carbonates, which depth of Paleocene-Eocene boundary from the core was discussed. Ostracode assemblages include the Sinocypris nitela-Cyprois buxinensis-Limnocythere honggangensis assemblage(89.0-73.38 m) with few species and low abundance and the Sinocypris nitela-Cyprois buxinensis-Limnocythere honggangensis assemblage (73.38-0 m) with few species and low abundance during early and middle the core deposition and relatively many species and abundance increasing quickly of the late time of the core deposition; Charophyte assemblages contain the Peckichara subspherica-Rhabdochara jiangduensis assemblage (89.0-73.38 m) with rich species, high abundance and large sizes of fossils and the Gyrogona qianjiangica-Obtusochara brevicylindrica assemblage (73.38-53.75 m) with few species,low abundance and small sizes of fossils. At 73.38 m core depth, the great changes of microfossils assemblages and carbon isotopes values (decrease by more than 3.0 per thousand) and oxygen isotopes values of bulk carbonates take place, which consist with the geological records of the Paleocene-Eocene Thermal Maximum (PETM). Hence, Paleocene-Eocene boundary of SanShui Basin should be roughly placed at 73.38 m core depth. (authors)

Coeval Eocene blooms of the freshwater fern Azolla in and around Arctic and Nordic seas

NARCIS (Netherlands)

Barke, J.; Burgh, A.H.P. van der; Konijnenburg-van Cittert, J.H.A. van; Collinson, M.E.; Pearce, M.A.; Bujak, J.; Heilman-Clausen, C.; Lotter, A.F.; Speelman, E.N.; Kempen, M.M.L. van; Reichart, G.-J.; Brinkhuis, H.

2012-01-01

For a short time interval (c. 1.2 Myr) during the early middle Eocene (~ 49 Myr), the central Arctic Ocean was episodically densely covered by the freshwater fern Azolla, implying sustained freshening of surface waters. Coeval Azolla fossils in neighboring Nordic seas were thought to have been

GREEN PACKAGING, GREEN PRODUCT, GREEN ADVERTISING, PERSEPSI, DAN MINAT BELI KONSUMEN

OpenAIRE

Imam Santoso; Rengganis Fitriani

2016-01-01

Environmental problems become one of the strategic issues in achieving global competitiveness. One of the issues is products that are made from environmental friendly materials or known as green product. Furthermore, in green products marketing, the company also uses green packaging and green advertising concept. This study aimed to analyze the effect of green packaging, green products, and green advertising on consumer perception and purchasing intention. The study was conducted in Ketawangg...

Goulds Belt, Interstellar Clouds, and the Eocene-Oligocene Helium-3 Spike

Science.gov (United States)

Rubincam, David Parry

2015-01-01

Drag from hydrogen in the interstellar cloud which formed Gould's Belt may have sent small meteoroids with embedded helium to the Earth, perhaps explaining part or all of the (sup 3) He spike seen in the sedimentary record at the Eocene-Oligocene transition. Assuming the Solar System passed through part of the cloud, meteoroids in the asteroid belt up to centimeter size may have been dragged to the resonances, where their orbital eccentricities were pumped up into Earth-crossing orbits.

Biostratigraphic implications of the first Eocene land-mammal fauna from the North American coastal plain

Science.gov (United States)

Westgate, James W.

1988-11-01

A newly discovered vertebrate fossil assemblage, the Casa Blanca local fauna, comes from the Laredo Formation, Claiborne Group, of Webb County, Texas, and is the first reported Eocene land-mammal fauna from the coastal plain of North America. The mammalian fauna is correlated with the Serendipity and Candelaria local faunas of west Texas, the Uinta C faunas of the Rocky Mountains, the Santiago Formation local fauna of southern California, and the Swift Current Creek local fauna of Saskatchewan. The vertebrate-bearing deposit lies about 32 m above a horizon containing the marine gastropod Turritella cortezi, which ranges from east Texas to northeast Mexico in the lower half of the Cook Mountain and Laredo Formations and is a guide fossil to the Hurricane Lentil in the Cook Mountain Formation. Nannoplankton found in these middle Eocene formations belong to the upper half of Nannoplankton Zone I6 and allow correlation with European beds of late Lutetian to early Bartonian age.

Justitia Holthuis, 1946 (Crustacea, Decapoda, Palinuridea) from the Middle Eocene of Verona and Vicenza (northern Italy)

NARCIS (Netherlands)

Garassino, Alessandro; Angeli, De Antonio

2003-01-01

Recently, Beschin et al. (2001) have described two specimens of palinurids, discovered at Chiampo (“Albanello” quarry, Vicenza, northern Italy). Preserved three dimensionally, these were collected from limestones of Lutetian (middle Eocene) age. The peculiar ornament of the dorsal carapace surface,

Complete primate skeleton from the Middle Eocene of Messel in Germany: morphology and paleobiology.

Directory of Open Access Journals (Sweden)

Jens L Franzen

2009-05-01

Full Text Available The best European locality for complete Eocene mammal skeletons is Grube Messel, near Darmstadt, Germany. Although the site was surrounded by a para-tropical rain forest in the Eocene, primates are remarkably rare there, and only eight fragmentary specimens were known until now. Messel has now yielded a full primate skeleton. The specimen has an unusual history: it was privately collected and sold in two parts, with only the lesser part previously known. The second part, which has just come to light, shows the skeleton to be the most complete primate known in the fossil record.We describe the morphology and investigate the paleobiology of the skeleton. The specimen is described as Darwinius masillae n.gen. n.sp. belonging to the Cercamoniinae. Because the skeleton is lightly crushed and bones cannot be handled individually, imaging studies are of particular importance. Skull radiography shows a host of teeth developing within the juvenile face. Investigation of growth and proportion suggest that the individual was a weaned and independent-feeding female that died in her first year of life, and might have attained a body weight of 650-900 g had she lived to adulthood. She was an agile, nail-bearing, generalized arboreal quadruped living above the floor of the Messel rain forest.Darwinius masillae represents the most complete fossil primate ever found, including both skeleton, soft body outline and contents of the digestive tract. Study of all these features allows a fairly complete reconstruction of life history, locomotion, and diet. Any future study of Eocene-Oligocene primates should benefit from information preserved in the Darwinius holotype. Of particular importance to phylogenetic studies, the absence of a toilet claw and a toothcomb demonstrates that Darwinius masillae is not simply a fossil lemur, but part of a larger group of primates, Adapoidea, representative of the early haplorhine diversification.

Eocene climate and Arctic paleobathymetry: A tectonic sensitivity study using GISS ModelE-R

Science.gov (United States)

Roberts, C. D.; Legrande, A. N.; Tripati, A. K.

2009-12-01

The early Paleogene (65-45 million years ago, Ma) was a ‘greenhouse’ interval with global temperatures warmer than any other time in the last 65 Ma. This period was characterized by high levels of CO2, warm high-latitudes, warm surface-and-deep oceans, and an intensified hydrological cycle. Sediments from the Arctic suggest that the Eocene surface Arctic Ocean was warm, brackish, and episodically enabled the freshwater fern Azolla to bloom. The precise mechanisms responsible for the development of these conditions remain uncertain. We present equilibrium climate conditions derived from a fully-coupled, water-isotope enabled, general circulation model (GISS ModelE-R) configured for the early Eocene. We also present model-data comparison plots for key climatic variables (SST and δ18O) and analyses of the leading modes of variability in the tropical Pacific and North Atlantic regions. Our tectonic sensitivity study indicates that Northern Hemisphere climate would have been very sensitive to the degree of oceanic exchange through the seaways connecting the Arctic to the Atlantic and Tethys. By restricting these seaways, we simulate freshening of the surface Arctic Ocean to ~6 psu and warming of sea-surface temperatures by 2°C in the North Atlantic and 5-10°C in the Labrador Sea. Our results may help explain the occurrence of low-salinity tolerant taxa in the Arctic Ocean during the Eocene and provide a mechanism for enhanced warmth in the north western Atlantic. We also suggest that the formation of a volcanic land-bridge between Greenland and Europe could have caused increased ocean convection and warming of intermediate waters in the Atlantic. If true, this result is consistent with the theory that bathymetry changes may have caused thermal destabilisation of methane clathrates in the Atlantic.

Complete primate skeleton from the Middle Eocene of Messel in Germany: morphology and paleobiology.

Science.gov (United States)

Franzen, Jens L; Gingerich, Philip D; Habersetzer, Jörg; Hurum, Jørn H; von Koenigswald, Wighart; Smith, B Holly

2009-05-19

The best European locality for complete Eocene mammal skeletons is Grube Messel, near Darmstadt, Germany. Although the site was surrounded by a para-tropical rain forest in the Eocene, primates are remarkably rare there, and only eight fragmentary specimens were known until now. Messel has now yielded a full primate skeleton. The specimen has an unusual history: it was privately collected and sold in two parts, with only the lesser part previously known. The second part, which has just come to light, shows the skeleton to be the most complete primate known in the fossil record. We describe the morphology and investigate the paleobiology of the skeleton. The specimen is described as Darwinius masillae n.gen. n.sp. belonging to the Cercamoniinae. Because the skeleton is lightly crushed and bones cannot be handled individually, imaging studies are of particular importance. Skull radiography shows a host of teeth developing within the juvenile face. Investigation of growth and proportion suggest that the individual was a weaned and independent-feeding female that died in her first year of life, and might have attained a body weight of 650-900 g had she lived to adulthood. She was an agile, nail-bearing, generalized arboreal quadruped living above the floor of the Messel rain forest. Darwinius masillae represents the most complete fossil primate ever found, including both skeleton, soft body outline and contents of the digestive tract. Study of all these features allows a fairly complete reconstruction of life history, locomotion, and diet. Any future study of Eocene-Oligocene primates should benefit from information preserved in the Darwinius holotype. Of particular importance to phylogenetic studies, the absence of a toilet claw and a toothcomb demonstrates that Darwinius masillae is not simply a fossil lemur, but part of a larger group of primates, Adapoidea, representative of the early haplorhine diversification.

Combined sewer overflows impact on water quality and environmental ecosystem in the Harlem River

Science.gov (United States)

Wang, J.

2017-12-01

Combined sewer overflows (CSOs) discharge untreated sewage into the Harlem River during wet weather conditions, and it elevated nutrients and pathogen levels. It is not safe for swimming, fishing or boating especially in rainstorms. The Harlem River, a 9.3 mile long natural straight, connects the Hudson and East Rivers in New York City. It had been historically used for swimming, fishing, boating. Anthropogenic impacts have degraded water quality, limiting current aquatic activity in the river. CSOs water samples were collected during rainstorms, and analyzed in the laboratories of the Chemistry and Biology Department, Bronx Community College, City University of New York. Results showed elevated bacteria/pathogen and nutrient levels. Most recent data showed an ammonia concentration of 2.6 mg/L on July 30, 2015 during a heavy afternoon thunderstorm, and an ammonia level 2.7mg/L during tropical storm Arthur on July 2, 2014. Both significantly exceeded the EPA regulation level for NYC waters of 0.23mg/L. Phosphate levels peaked at 0.197 mg/L during a heavy thunderstorm on Apr 28, 2011, which was much higher than regulated level of 0.033 mg/L. Turbidity was 319 FAU during the July 30 2015 heavy thunderstorm, and was 882 FAU during tropical storm Arthur; which was significantly higher than regulation level of 5.25 FAU. CSOs collected during a recent heavy rainstorm on Oct 28, 2015, showed fecal coliform of 1 million MPN/100ml, E.Coli. of 60,000 MPN/100ml, and enterococcus of 65,000 MPN/100ml; which exceeded regulated levels of fecal coliform-200 MPN/100ml, E.Coli.-126 MPN/100ml, enterococcus-104 MPN/100ml. It is critical to reduce CSOs, restore ecosystem and improve water quality of the Harlem River. Green wall, green roof, and wetland had been used to reduce stormwater runoff & CSOs in the Bronx River; these green infrastructures are going to be used along the Harlem River waterfront as well. The goal of this research is to make the Harlem River swimmable and fishable

Update on Kansas City Middle Blue River Green Infrastructure Pilot Project

Science.gov (United States)

In 2010, Kansas City, MO (KCMO) signed a consent degree with EPA on combined sewer overflows. The City decided to use adaptive management in order to extensively utilize green infrastructure (GI) in lieu of, and in addition to, gray structural controls. KCMO installed 130 GI sto...

Favorability for uranium in tertiary sedimentary rocks, southwestern Montana

International Nuclear Information System (INIS)

Wopat, M.A.; Curry, W.E.; Robins, J.W.; Marjaniemi, D.K.

1977-10-01

Tertiary sedimentary rocks in the basins of southwestern Montana were studied to determine their favorability for potential uranium resources. Uranium in the Tertiary sedimentary rocks was probably derived from the Boulder batholith and from silicic volcanic material. The batholith contains numerous uranium occurrences and is the most favorable plutonic source for uranium in the study area. Subjective favorability categories of good, moderate, and poor, based on the number and type of favorable criteria present, were used to classify the rock sequences studied. Rocks judged to have good favorability for uranium deposits are (1) Eocene and Oligocene strata and undifferentiated Tertiary rocks in the western Three Forks basin and (2) Oligocene rocks in the Helena basin. Rocks having moderate favorability consist of (1) Eocene and Oligocene strata in the Jefferson River, Beaverhead River, and lower Ruby River basins, (2) Oligocene rocks in the Townsend and Clarkston basins, (3) Miocene and Pliocene rocks in the Upper Ruby River basin, and (4) all Tertiary sedimentary formations in the eastern Three Forks basin, and in the Grasshopper Creek, Horse Prairie, Medicine Lodge Creek, Big Sheep Creek, Deer Lodge, Big Hole River, and Bull Creek basins. The following have poor favorability: (1) the Beaverhead Conglomerate in the Red Rock and Centennial basins, (2) Eocene and Oligocene rocks in the Upper Ruby River basin, (3) Miocene and Pliocene rocks in the Townsend, Clarkston, Smith River, and Divide Creek basins, (4) Miocene through Pleistocene rocks in the Jefferson River, Beaverhead River, and Lower Ruby River basins, and (5) all Tertiary sedimentary rocks in the Boulder River, Sage Creek, Muddy Creek, Madison River, Flint Creek, Gold Creek, and Bitterroot basins

Strategic Planning for the Smart-Green City through Urban Governance

Directory of Open Access Journals (Sweden)

Kwang Hyun Yim

2015-09-01

Full Text Available Green city is a city seeking for transition from a traditional city paradigm to a sustainable city based on the principles of nature as circulation, coexistence and balance in a response to climate change. Cheongju City has been trying to find its identity as a green capital of Korea, and attempts to develop the policy packages to build the green capital in response to climate change. This study intends to analyze a transition master plan for the green city and to set policy priorities through governance. This study employs participatory approaches including focus group interviews, experts’ advisory meetings, and survey. This study also develops indicators to evaluate the importance of the values of green city through an expert Analytic Hierarchy Process (AHP survey method. Then, set policy priorities of green city based on the evaluation results. The vision and strategies were derived through consecutive group discussions between various stakeholders consisted of professors, NGOs, and local government officials for several months. The vision was composed of ten strategies, for example, building circular networks of local material and establishing community-based economic system etc. This study has set policy priorities based on the evaluation of green city’s values of each policy. It is found that the top five policies were building Moosim-chon, river of life and citizens forests, diagnosis and innovation of administration system, mapping biotope and climate, operating car-free streets and building 1000 pocket parks.

Reinterpretation of Azolla primaeva (Azollaceae, Eocene, Canada) using electron microscopy and X-ray tomographic microscopy

NARCIS (Netherlands)

Collinson, Margaret E.; van Konijnenburg-van Cittert, Johanna H.A.; Marone, Federica; Brain, Anthony P.R.

Azolla primaeva (Penhallow) Arnold fertile whole plants from the lower Eocene of Driftwood Creek, Canada have been examined using LM, SEM, TEM and SRXTM methods on hand specimens and sieved residues. The new data have resulted in an emended diagnosis. The megaspore is partly covered by filosum and

Geochemical and Petrologic Constraints on the Source of Eocene Volcanism at Mole Hill, Rockingham County, VA

Science.gov (United States)

Johnson, E. A.; Beard, J. S.

2010-12-01

Mole Hill is an Eocene (48 Ma) basaltic volcanic neck located west of Harrisonburg, VA, and provides a unique opportunity to probe the mantle beneath the Shenandoah Valley. It lies on the northeastern edge of a swarm of alkaline-series volcanic plugs, dikes, and diatremes extending through Rockingham and Highland Counties, VA, and Pendleton County, WV. The Eocene volcanics are thought to have exploited extensive basement fracture systems originally formed during the Alleghenian Orogeny and subsequent rifting. The Eocene volcanism may have been triggered by reactivation of faults due to global shifts in relative plate motions (Southworth 1993, USGS Bull, B1839-I) but the source material and magmatic processes for the Eocene volcanism are largely unknown. Compositional and texture analyses of xenocrystic and groundmass clinopyroxene, olivine, and spinel were completed either at Virginia Tech on the Cameca SX-50 electron microprobe in the Dept of Geological Sciences, or in the Dept of Mineral Sciences, Smithsonian Institution, Washington, D.C using the JEOL JXA-8900R WD/EDS microanalyzer or the FEI NOVA nanoSEM600 FEG Variable Pressure Scanning Electron Microscope. Xenocrysts up to 2cm in diameter are distributed throughout the volcanic neck, with clinopyroxene >>spinel>olivine. The clinopyroxene and olivine xenocrysts show undulatory extinction in cross-polarized light and are found as individual crystals or as aggregates. Clinopyroxene xenocryst cores are high-Al, low-Cr augite ( ˜Wo44En46Fs10) with Mg# 78.5-85.9. The clinopyroxene xenocrysts have compositionally zoned rims 100-250 μm-wide containing abundant plagioclase inclusions and sparse melt inclusions in a sieve texture. The outer edges of xenocrysts approach the compositions of groundmass and microphenocryst clinopyroxenes ( ˜Wo47En38Fs15; Mg# 67.9-74.5). Olivine xenocrysts contain sulfide inclusions and Cr-rich spinel and have Mg-rich ( ˜Fo86-90) cores with more Fe- and Ca-rich rims (Fo70

Preliminary study of uranium favorability of upper cretaceous, paleocene, and lower eocene rocks of the Bighorn Basin, Wyoming and Montana

International Nuclear Information System (INIS)

Hesse, S.L.; Dunagan, J.F. Jr.

1978-02-01

This report presents an evaluation of the uranium favorability of continental sediments of the Upper Cretaceous Lance, Paleocene Polecat Bench, and lower Eocene Willwood Formations in the Bighorn Basin of Wyoming and Montana, an intermontane structural basin of Laramide age. Previous work dealing with the Bighorn Basin was reviewed, and field investigations were carried out in the spring and summer of 1976. Subsurface data were collected and results of surface and subsurface investigations were evaluated with respect to uranium favorability. Precambrian plutonic and metamorphic rocks and Tertiary tuffaceous rocks in the Bighorn Basin and bordering uplifts are considered insignificant as source rocks, although the Wiggins Formation (White River equivalent) cannot be evaluated as a possible source because of a lack of data. Potential host rocks locally show only limited favorability. Lithology of strata exposed along the western and southern basin margins is more favorable than that of rocks in the central and eastern parts of the basin, but there is little organic material, pyrite, or other reducing agents in these rocks. Strata of the Lance, Polecat Bench, and Willwood Formations in the Bighorn Basin are considered generally unfavorable for sandstone uranium deposits

Greens of the European Green Capitals

Science.gov (United States)

Cömertler, Seval

2017-10-01

Well established and maintained green areas have a key role on reaching the high quality of life and sustainability in urban environments. Therefore, green areas must be carefully accounted and evaluated in the urban planning affairs. In this context, the European Green Capitals, which attach a great importance to the green areas, have a great potential to act as a role model for both small and big cities in all around the world. These leading cities (chronologically, Stockholm, Hamburg, Vitoria-Gasteiz, Nantes, Copenhagen, Bristol, Ljubljana, Essen and Nijmegen) are inspiring for the other cities which seek to achieve more sustainable and environmentally friendly places through green areas. From this point of view, the aim of this paper was to investigate the green areas of the European Green Capitals. The paper covered whole European Green Capitals, and the application form of each Green Capital was used as a primary data source. Consequently, the paper put forwarded that the European Green Capitals have considerably large amount and high proportion of green areas. Further, these cities provide an excellent access to the public green areas. As a result of abundant provision and proper distribution, the almost all citizens in most of the Green Capitals live within a distance of 300 meters to a green area. For further researches, the paper suggested that these green capitals should be investigated in terms of their efforts, measures, goals and plans, policies and implications to administer, to protect, to enhance and to expand the green areas.

The geological position, sedimentary record and composition of the Tylicz Conglomerate (Late Eocene-Oligocene): stratigraphical and paleogeographical implications (Magura Nappe, Polish Outer Carpathians)

Science.gov (United States)

Olszewska, Barbara; Oszczypko, Nestor

2010-02-01

During the Late Cretaceous to Paleogene the Magura Basin was supplied with clastic material from, non-existing today, source areas situated on the northern and southern margins of the basin. The northern source area is traditionally connected with Silesian Ridge, whereas the position of the southern one is still under discussion. The Upper Eocene-Oligocene pebbly mudstones of the Tylicz/Krynica facies zone contain exotic material derived from the south-Magura source area. The studied pebbles and clasts contain fragments of crystalline rocks, derived from a continental type of crust, and frequent clasts of Mesozoic to Paleogene deep and shallow-water limestones. Volcanites, rarely granitoides as well as schists, gneisses, quartzites and cataclasites were found in the group of crystalline exotic pebbles. The isotopic ages of "exotic" pebbles from the Tylicz section document a Variscan age of plutonic and metamorphic rocks. The composition of the Tylicz exotic conglomerates occupied the transitional position between the Jarmuta/Proč (Maastrichtian-Lower Eocene) and Strihovce (Eocene) exotic pebbles. The provenance of these rocks could be connected with Eocene exhumation of the SE sector of the Magura Basin basement. Another possibility can be explain by supply of siliciclastic material from a SE source area (Dacia and Tisza Mega-Units) and carbonate material from a S source area (ALCAPA Mega-Unit: Central Carpathian Block and Pieniny Klippen Belt).

Ironstone deposits hosted in Eocene carbonates from Bahariya (Egypt)-New perspective on cherty ironstone occurrences

Science.gov (United States)

Afify, A. M.; Sanz-Montero, M. E.; Calvo, J. P.

2015-11-01

This paper gives new insight into the genesis of cherty ironstone deposits. The research was centered on well-exposed, unique cherty ironstone mineralization associated with Eocene carbonates from the northern part of the Bahariya Depression (Egypt). The economically important ironstones occur in the Naqb Formation (Early Eocene), which is mainly formed of shallow marine carbonate deposits. Periods of lowstand sea-level caused extensive early dissolution (karstification) of the depositional carbonates and dolomitization associated with mixing zones of fresh and marine pore-water. In faulted areas, the Eocene carbonate deposits were transformed into cherty ironstone with preservation of the precursor carbonate sedimentary features, i.e. skeletal and non-skeletal grain types, thickness, bedding, lateral and vertical sequential arrangement, and karst profiles. The ore deposits are composed of iron oxyhydroxides, mainly hematite and goethite, chert in the form of micro- to macro-quartz and chalcedony, various manganese minerals, barite, and a number of subordinate sulfate and clay minerals. Detailed petrographic analysis shows that quartz and iron oxides were coetaneous and selectively replaced carbonates, the coarse dolomite crystals having been preferentially transformed into quartz whereas the micro-crystalline carbonates were replaced by the iron oxyhydroxides. A number of petrographic, sedimentological and structural features including the presence of hydrothermal-mediated minerals (e.g., jacobsite), the geochemistry of the ore minerals as well as the structure-controlled location of the mineralization suggest a hydrothermal source for the ore-bearing fluids circulating through major faults and reflect their proximity to centers of magmatism. The proposed formation model can contribute to better understanding of the genetic mechanisms of formation of banded iron formations (BIFs) that were abundant during the Precambrian.

Multi-proxy Paleoclimate and CO2 Reconstruction from the Latest Middle Eocene Sedimentary Fill of a Subarctic Kimberlitic Maar Crater

Science.gov (United States)

Reyes, A. V.; Wolfe, A. P.; Royer, D. L.; Greenwood, D. R.; Tierney, J. E.; Doria, G.; Gagen, M. H.; Siver, P.; Westgate, J.

2016-12-01

Eocene paleoclimate reconstructions are rarely accompanied by parallel estimates of CO2, complicating assessment of the equilibrium climate responses to CO2. We reconstruct temperature, precipitation, and CO2 from latest middle Eocene ( 38 Myrs ago) peats in subarctic Canada, preserved in sediments that record infilling of a kimberlite pipe maar crater. Mutual climatic range analyses of pollen, together with oxygen isotope analyses of a-cellulose from unpermineralized wood and inferenecs from branched glycerol diakyl glycerol tetraethers (GDGTs), reveal a high-latitude humid-temperate forest ecosystem with mean annual temperatures (MATs) >17 °C warmer than present, mean coldest month temperatures above 0 °C, and mean annual precipitation 4x present. Metasequoia stomatal indices and gas-exchange modeling produce median CO2 concentrations of 634 and 432 ppm, respectively, with a consensus median estimate of 494 ppm. Reconstructed MATs are >6 °C warmer than those produced by Eocene climate models forced at 560 ppm CO2, underscoring the capacity for exceptional polar amplification of warming and hydrological intensification under relatively modest CO2 concentrations, once both fast and slow feedbacks become expressed.

Star River, A Champion of High-end Residence

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

@@ Star River(or Star Bay), an elite works of Hong Yu Group, is located in Sijixinghe Road, Chaoyang District, Beijing. It is a distinguished residence area, occupying land of 300 thousand sq.meters. The north side is a forest garden with 1600 or more mu, the eastern side is a green belt with more than 2000 mu.

Algal diversity of Adada River, Nigeria. I. Chlorophyta (green algae ...

African Journals Online (AJOL)

Commercial water tankers collect water and sell to indigenes and towns around the river, hence the need to investigate the algal biodiversity in other to access its suitability for human consumption using known algal indicators of water quality and add to the pool of data useful for long term trends in floral composition in ...

Detection of Adult Green Sturgeon Using Environmental DNA Analysis.

Directory of Open Access Journals (Sweden)

Paul S Bergman

Full Text Available Environmental DNA (eDNA is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS of North American Green Sturgeon located in California's Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods.

From green architecture to architectural green

DEFF Research Database (Denmark)

Earon, Ofri

2011-01-01

that describes the architectural exclusivity of this particular architecture genre. The adjective green expresses architectural qualities differentiating green architecture from none-green architecture. Currently, adding trees and vegetation to the building’s facade is the main architectural characteristics...... they have overshadowed the architectural potential of green architecture. The paper questions how a green space should perform, look like and function. Two examples are chosen to demonstrate thorough integrations between green and space. The examples are public buildings categorized as pavilions. One......The paper investigates the topic of green architecture from an architectural point of view and not an energy point of view. The purpose of the paper is to establish a debate about the architectural language and spatial characteristics of green architecture. In this light, green becomes an adjective...

Earliest Mysticete from the Late Eocene of Peru Sheds New Light on the Origin of Baleen Whales.

Science.gov (United States)

Lambert, Olivier; Martínez-Cáceres, Manuel; Bianucci, Giovanni; Di Celma, Claudio; Salas-Gismondi, Rodolfo; Steurbaut, Etienne; Urbina, Mario; de Muizon, Christian

2017-05-22

Although combined molecular and morphological analyses point to a late middle Eocene (38-39 million years ago) origin for the clade Neoceti (Odontoceti, echolocating toothed whales plus Mysticeti, baleen whales, and relatives), the oldest known mysticete fossil dates from the latest Eocene (about 34 million years ago) of Antarctica [1, 2]. Considering that the latter is not the most stemward mysticete in recent phylogenies and that Oligocene toothed mysticetes display a broad morphological disparity most likely corresponding to contrasted ecological niches, the origin of mysticetes from a basilosaurid ancestor and its drivers are currently poorly understood [1, 3-8]. Based on an articulated cetacean skeleton from the early late Eocene (Priabonian, around 36.4 million years ago) of the Pisco Basin, Peru, we describe a new archaic tooth-bearing mysticete, Mystacodon selenensis gen. et sp. nov. Being the geologically oldest neocete (crown group cetacean) and the earliest mysticete to branch off described so far, the new taxon is interpreted as morphologically intermediate between basilosaurids and later toothed mysticetes, providing thus crucial information about the anatomy of the skull, forelimb, and innominate at these critical initial stages of mysticete evolution. Major changes in the morphology of the oral apparatus (including tooth wear) and flipper compared to basilosaurids suggest that suction and possibly benthic feeding represented key, early ecological traits accompanying the emergence of modern filter-feeding baleen whales' ancestors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Paleocene-Eocene and Plio-Pleistocene sea-level changes as "species pumps" in Southeast Asia: Evidence from Althepus spiders.

Science.gov (United States)

Li, Fengyuan; Li, Shuqiang

2018-05-17

Sea-level change has been viewed as a primary driver in the formation of biodiversity. Early studies confirmed that Plio-Pleistocene sea-level changes led to the isolation and subsequent genetic differentiation of Southeast (SE) Asian organisms over short geological timescales. However, long-time consequences of sea-level fluctuations remain unclear. Herein, we analyze the evolutionary history of Althepus (spiders) whose distribution encompasses Indo-Burma and the Sunda shelf islands to understand how sea-level changes over shallow and deep timescales effected their history. Our integrative analyses, including phylogeny, divergence times, ancestral area reconstruction and diversification dynamics, reveal an intricate pattern of diversification, probably triggered by sea-level fluctuations during the Paleocene-Eocene and Plio-Pleistocene. The timing of one early divergence between the Indo-Burmese and Sundaic species coincides with late Paleocene and early Eocene high global sea levels, which induced the formation of inland seaways in the Thai-Malay Peninsula. Subsequent lowered sea levels could have provided a land bridge for its dispersal colonization across the Isthmus of Kra. Analyses suggest that Plio-Pleistocene sea-level rises contributed to recent divergence of many species. Thus, our findings cannot reject the hypothesis that sea-level changes during the Paleocene-Eocene and Plio-Pleistocene played a major role in generating biodiversity in SE Asia; sea-level changes can act as "species pumps". Copyright © 2018 Elsevier Inc. All rights reserved.

The initiation and evolution of the River Nile

Science.gov (United States)

Fielding, Laura; Najman, Yani; Millar, Ian; Butterworth, Peter; Garzanti, Eduardo; Vezzoli, Giovanni; Barfod, Dan; Kneller, Ben

2018-05-01

The Nile is generally regarded as the longest river in the world. Knowledge of the timing of the Nile's initiation as a major river is important to a number of research questions. For example, the timing of the river's establishment as a catchment of continental proportions can be used to document surface uplift of its Ethiopian upland drainage, with implications for constraining rift tectonics. Furthermore, the time of major freshwater input to the Mediterranean is considered to be an important factor in the development of sapropels. Yet the river's initiation as a major drainage is currently constrained no more precisely than Eocene to Pleistocene. Within the modern Nile catchment, voluminous Cenozoic Continental Flood Basalts (CFBs) are unique to the Ethiopian Highlands; thus first detection of their presence in the Nile delta record indicates establishment of the river's drainage at continental proportions at that time. We present the first detailed multiproxy provenance study of Oligocene-Recent Nile delta cone sediments. We demonstrate the presence of Ethiopian CFB detritus in the Nile delta from the start of our studied record (c. 31 Ma) by (1) documenting the presence of zircons with U-Pb ages unique, within the Nile catchment, to the Ethiopian CFBs and (2) using Sr-Nd data to construct a mixing model which indicates a contribution from the CFBs. We thereby show that the Nile river was established as a river of continental proportions by Oligocene times. We use petrography and heavy mineral data to show that previous petrographic provenance studies which proposed a Pleistocene age for first arrival of Ethiopian CFBs in the Nile delta did not take into account the strong diagenetic influence on the samples. We use a range of techniques to show that sediments were derived from Phanerozoic sedimentary rocks that blanket North Africa, Arabian-Nubian Shield basement terranes, and Ethiopian CFB's. We see no significant input from Archaean cratons supplied

Antarctic glaciation caused ocean circulation changes at the Eocene-Oligocene transition.

Science.gov (United States)

Goldner, A; Herold, N; Huber, M

2014-07-31

Two main hypotheses compete to explain global cooling and the abrupt growth of the Antarctic ice sheet across the Eocene-Oligocene transition about 34 million years ago: thermal isolation of Antarctica due to southern ocean gateway opening, and declining atmospheric CO2 (refs 5, 6). Increases in ocean thermal stratification and circulation in proxies across the Eocene-Oligocene transition have been interpreted as a unique signature of gateway opening, but at present both mechanisms remain possible. Here, using a coupled ocean-atmosphere model, we show that the rise of Antarctic glaciation, rather than altered palaeogeography, is best able to explain the observed oceanographic changes. We find that growth of the Antarctic ice sheet caused enhanced northward transport of Antarctic intermediate water and invigorated the formation of Antarctic bottom water, fundamentally reorganizing ocean circulation. Conversely, gateway openings had much less impact on ocean thermal stratification and circulation. Our results support available evidence that CO2 drawdown--not gateway opening--caused Antarctic ice sheet growth, and further show that these feedbacks in turn altered ocean circulation. The precise timing and rate of glaciation, and thus its impacts on ocean circulation, reflect the balance between potentially positive feedbacks (increases in sea ice extent and enhanced primary productivity) and negative feedbacks (stronger southward heat transport and localized high-latitude warming). The Antarctic ice sheet had a complex, dynamic role in ocean circulation and heat fluxes during its initiation, and these processes are likely to operate in the future.

Remedial Action Plan and final design for stabilization of the inactive uranium mill tailings at Green River, Utah. Volume 1, Text, Appendices A, B, and C: Final report

Energy Technology Data Exchange (ETDEWEB)

Matthews, M.L. [USDOE Albuquerque Operations Office, NM (United States). Uranium Mill Tailings Remedial Action Project Office; Alkema, K. [Utah Dept. of Health, Salt Lake City, UT (United States). Environmental Health Div.

1991-03-01

This Remedial Action Plan (RAP) has been developed to serve a threefold purpose. It presents the series of activities that are proposed by the US Department of Energy (DOE) to accomplish long-term stabilization and control of radioactive materials at the inactive uranium processing site located near Green River, Utah. It provides a characterization of the present conditions of the site. It also serves to document the concurrence of the state of Utah and the US Nuclear Regulatory Commission (NRC) in the remedial action. This agreement, upon execution by the DOE and the state of Utah, and concurrence by the NRC, becomes Appendix 8 of the Cooperative Agreement.

The Influence of Proactive Green Innovation and Reactive Green Innovation on Green Product Development Performance: The Mediation Role of Green Creativity

Directory of Open Access Journals (Sweden)

Yu-Shan Chen

2016-09-01

Full Text Available This study fills the research gap in the exploration of the relationships between both proactive and reactive green innovations and green product development performance, and examines the mediating effect of green creativity. Structural equation modeling (SEM is utilized to test the hypotheses. From the sample of 146 valid respondents, the results show that proactive green innovation positively affects green creativity and green product development performance, and green creativity positively affects green product development performance. In addition, our findings also indicate that the relationship between proactive green innovation and green product development performance is partially mediated by green creativity. Accordingly, green creativity plays a critical role for companies to achieve a great green product development performance. However, reactive green innovation does not significantly influence green creativity and green product development performance. Companies should develop proactive green innovation rather than reactive green innovation in order to enhance their green creativity and increase their product development performance.

Diachronous seawater retreat from the southwestern margin of the Tarim Basin in the late Eocene

NARCIS (Netherlands)

Sun, Jimin; Windley, Brian F.; Zhang, Zhiliang; Fu, Bihong; Li, Shihu|info:eu-repo/dai/nl/411296248

In contrast to the present hyper-arid inland basin surrounded by the high mountains of Central Asia, the western Tarim Basin was once connected with the Tajik Basin at least in the late Eocene, when an epicontinental sea extended from the western Tarim Basin to Europe. Western Tarim is a key site

Pengaruh Green Marketing Hotel Terhadap Green Consumer Behavior

OpenAIRE

Yo Fernandez, Eunike Christe; Tjoanda, Evelyn

2017-01-01

Penelitian ini dilakukan untuk mengetahui pengaruh dari green marketing hotel terhadap green consumer behavior. Green marketing memiliki 3 dimensi, yaitu green product, green price, dan green promotion. Penelitian ini melibatkan 272 responden masyarakat Surabaya dan menggunakan metode regresi linear berganda. Hasil penelitian menunjukkan bahwa green product dan green price berpengaruh secara positif dan signifikan sedangkan green promotion berpengaruh namun tidak signifikan terhadap green con...

Use of aerial videography to evaluate the effects of Flaming Gorge Dam operations on natural resources of the Green River

International Nuclear Information System (INIS)

Snider, M.A.; Hayse, J.W.; Hlohowskyj, I.; LaGory, K.E.; Greaney, M.M.; Kuiper, J.A.; Van Lonkhuyzen, R.A.

1993-01-01

Peaking hydropower operations can profoundly alter natural stream flow and thereby affect the natural resources dependent on these flows. In this paper, we describe how aerial videography was used to collect environmental data and evaluate impacts of hydropower operations at Flaming Gorge Dam on natural resources of the Green River. An airborne multispectral video/radiometer remote sensing system was used to collect resource data under four different flow conditions from seven sites (each about one mile in length) located downstream from the dam. Releases from Flaming Gorge Dam during data collection ranged from approximately 800 to 4,000 cubic feet/sec (cfs), spanning most of the normal operating range for this facility. For each site a series of contiguous, non-overlapping images was prepared from the videotapes and used to quantify surface water area, backwater habitats, and areas of riparian vegetation under varying flow conditions. From this information, relationships between flow and habitat parameters were developed and used in conjunction with hydrologic modeling and ecological information to evaluate impacts of various modes of operation

The Eocene-Oligocene transition in the North Alpine Foreland Basin and subsequent closure of a Paratethys gateway

NARCIS (Netherlands)

van der Boon, A.; Beniest, A.; Ciurej, A.; Gaździcka, E.; Grothe, A.; Sachsenhofer, R. F.; Langereis, C. G.; Krijgsman, W.

During the Eocene-Oligocene transition (EOT), a major palaeoenvironmental change took place in the Paratethys Sea of central Eurasia. Restricted connectivity and increased stratification resulted in wide-spread deposition of organic-rich sediments which nowadays make up important hydrocarbon source

Flow regime effects on mature Populus fremontii (Fremont cottonwood) productivity on two contrasting dryland river floodplains

Science.gov (United States)

Andersen, Douglas C.

2016-01-01

I compared riparian cottonwood (Populus fremontii) productivity-discharge relationships in a relictual stand along the highly regulated Green River and in a naturally functioning stand along the unregulated Yampa River in semiarid northwest Colorado. I used multiple regression to model flow effects on annual basal area increment (BAI) from 1982 to 2011, after removing any autocorrelation present. Each BAI series was developed from 20 trees whose mean size (67 cm diameter at breast height [DBH]) was equivalent in the two stands. BAI was larger in the Yampa River stand except in 2 y when defoliating leaf beetles were present there. I found no evidence for a Yampa flood-magnitude threshold above which BAI declined. Flow variables explained ∼45% of residual BAI variability, with most explained by current-year maximum 90-d discharge (QM90) in the Yampa River stand and by a measure of the year-to-year change in QM90 in the Green River stand. The latter reflects a management-imposed ceiling on flood magnitude—Flaming Gorge Dam power plant capacity—infrequently exceeded during the study period. BAI in the relictual stand began to trend upward in 1992 when flows started to mimic a natural flow regime. Mature Fremont cottonwoods appear to be ecologically resilient. Their productivity along regulated rivers might be optimized using multiyear environmental flow designs.

Development of streamflow projections under changing climate conditions over Colorado River basin headwaters

Directory of Open Access Journals (Sweden)

W. P. Miller

2011-07-01

Full Text Available The current drought over the Colorado River Basin has raised concerns that the US Department of the Interior, Bureau of Reclamation (Reclamation may impose water shortages over the lower portion of the basin for the first time in history. The guidelines that determine levels of shortage are affected by relatively short-term (3 to 7 month forecasts determined by the Colorado Basin River Forecast Center (CBRFC using the National Weather Service (NWS River Forecasting System (RFS hydrologic model. While these forecasts by the CBRFC are useful, water managers within the basin are interested in long-term projections of streamflow, particularly under changing climate conditions. In this study, a bias-corrected, statistically downscaled dataset of projected climate is used to force the NWS RFS utilized by the CBRFC to derive projections of streamflow over the Green, Gunnison, and San Juan River headwater basins located within the Colorado River Basin. This study evaluates the impact of changing climate to evapotranspiration rates and contributes to a better understanding of how hydrologic processes change under varying climate conditions. The impact to evapotranspiration rates is taken into consideration and incorporated into the development of streamflow projections over Colorado River headwater basins in this study. Additionally, the NWS RFS is modified to account for impacts to evapotranspiration due to changing temperature over the basin. Adjusting evapotranspiration demands resulted in a 6 % to 13 % average decrease in runoff over the Gunnison River Basin when compared to static evapotranspiration rates. Streamflow projections derived using projections of future climate and the NWS RFS provided by the CBRFC resulted in decreased runoff in 2 of the 3 basins considered. Over the Gunnison and San Juan River basins, a 10 % to 15 % average decrease in basin runoff is projected through the year 2099. However, over the Green River basin, a 5 % to 8

Detrital U-Pb zircon analysis of an Eocene McMurdo Erratic sandstone, McMurdo Sound, Antarctica

International Nuclear Information System (INIS)

Paulsen, T.; Encarnacion, J.; Valencia, V.A.; Roti Roti, J.M.; Rasoazanamparany, C.

2011-01-01

Some of the most important Cenozoic sedimentary rocks in Antarctica are glacial erratics of fossiliferous Palaeogene to Neogene siliclastic rocks known as the McMurdo Erratics. Detrital zircon U-Pb isotopic data reported herein provide new information on the provenance of these siliciclastic rocks. The U-Pb age data from a sandstone glacial erratic that is likely of Eocene age show a dominant age cluster that ranges from 488 to 635 Ma, accompanied by subsidiary Neoproterozoic-Archaean peaks. The dominant Neoproterozoic-Ordovician age cluster, in conjunction with the arkosic lithologies of some erratics and the local presence of granitic and metasedimentary clasts, indicates that the Neoproterozoic-Ordovician basement complex of the Transantarctic Mountains likely served as a major source for the Eocene siliciclastic sediments. This is consistent with derivation of the McMurdo Erratics from locations proximal to the Transantarctic Mountains such as the Discovery Deep and/or major mountain outlet glacier areas. (author). 19 refs., 3 figs., 1 tab.

Bizarre tubercles on the vertebrae of Eocene fossil birds indicate an avian disease without modern counterpart

Science.gov (United States)

Mayr, Gerald

2007-08-01

Remains of fossil birds with numerous bony tubercles on the cervical vertebrae are reported from the Middle Eocene of Messel in Germany and the Late Eocene of the Quercy fissure fillings in France. These structures, which are unknown from extant birds and other vertebrates, were previously described for an avian skeleton from Messel but considered a singular feature of this specimen. The new fossils are from a different species of uncertain phylogenetic affinities and show that tuberculated vertebrae have a wider taxonomic, temporal, and geographic distribution. In contrast to previous assumptions, they are no ontogenetic feature and arise from the vertebral surface. It is concluded that they are most likely of pathologic origin and the first record of a Paleogene avian disease. Their regular and symmetrical arrangement over most of the external vertebral surface indicates a systemic disorder caused by factors that do not affect extant birds, such as especially high-dosed phytohormones or extinct pathogens.

Analysis of systematic fracturing in Eocene flsch of the Slovenian coastal region

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Marko Vrabec

2017-12-01

Full Text Available We analyse systematic fractures occurring in sandstone beds in Eocene flsch of the Slovenian coastal area. Two nearly perpendicular fracture sets were identifid: fractures F1 are generally NW-SE oriented, wellexpressed and predominately planar, whereas fractures F2 are NE-SW-striking, shorter, more irregular in shape, and terminate against the F1 set. The average orientation of both sets does not change signifiantly in a coastal transect crossing all principal structural domains of the area. We analysed fracture spacing with respect to layer thickness and determined fracture spacing index for both fracture sets. We interpret both fracture sets as tensional (Mode I joints originating in two distinct extensional episodes. Set F1 is older and formed in NE-SW directed tension which we correlate with the well-documented regional post-Dinaric orogen-perpendicular extension of presumably mid-Miocene age. Set F2 formed in NW-SE oriented tension, which is compatible with previously documented NE-SW-striking normal faults occurring in the area, but was so far not documented elsewhere. We interpret that F1 fractures predate folding and thrusting in the coastal belt. Earlier, Eocene-Oligocene Dinaric thrusting therefore did not signifiantly affect the coastal area, whereas post-F1 shortening, associated with northward indentation and underthrusting of the Adria microplate, did not commence before late Miocene.

Oceanographic data collected from Marsh Island (USCG day mark green 21) by Center for Coastal Margin Observation and Prediction (CMOP) and assembled by Northwest Association of Networked Ocean Observation Systems (NANOOS) in the Columbia River Estuary and North East Pacific Ocean from 2001-09-17 to 2006-10-12 (NCEI Accession 0162177)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0162177 contains navigational and physical data collected at Marsh Island (USCG day mark green 21), a fixed station in the Columbia River estuary -...

Linking Late Cretaceous to Eocene Tectonostratigraphy of the San Jacinto Fold Belt of NW Colombia With Caribbean Plateau Collision and Flat Subduction

Science.gov (United States)

Mora, J. Alejandro; Oncken, Onno; Le Breton, Eline; Ibánez-Mejia, Mauricio; Faccenna, Claudio; Veloza, Gabriel; Vélez, Vickye; de Freitas, Mario; Mesa, Andrés.

2017-11-01

Collision with and subduction of an oceanic plateau is a rare and transient process that usually leaves an indirect imprint only. Through a tectonostratigraphic analysis of pre-Oligocene sequences in the San Jacinto fold belt of northern Colombia, we show the Late Cretaceous to Eocene tectonic evolution of northwestern South America upon collision and ongoing subduction with the Caribbean Plate. We linked the deposition of four fore-arc basin sequences to specific collision/subduction stages and related their bounding unconformities to major tectonic episodes. The Upper Cretaceous Cansona sequence was deposited in a marine fore-arc setting in which the Caribbean Plate was being subducted beneath northwestern South America, producing contemporaneous magmatism in the present-day Lower Magdalena Valley basin. Coeval strike-slip faulting by the Romeral wrench fault system accommodated right-lateral displacement due to oblique convergence. In latest Cretaceous times, the Caribbean Plateau collided with South America marking a change to more terrestrially influenced marine environments characteristic of the upper Paleocene to lower Eocene San Cayetano sequence, also deposited in a fore-arc setting with an active volcanic arc. A lower to middle Eocene angular unconformity at the top of the San Cayetano sequence, the termination of the activity of the Romeral Fault System, and the cessation of arc magmatism are interpreted to indicate the onset of low-angle subduction of the thick and buoyant Caribbean Plateau beneath South America, which occurred between 56 and 43 Ma. Flat subduction of the plateau has continued to the present and would be the main cause of amagmatic post-Eocene deposition.

On a grain of sand - a microhabitat for the opportunistic agglutinated foraminifera Hemisphaerammina apta n. sp., from the early Eocene Arctic Ocean

Science.gov (United States)

McNeil, David H.; Neville, Lisa A.

2018-02-01

Hemisphaerammina apta n. sp. is an attached monothalamous agglutinated foraminifera discovered in shelf sediments of the early Eocene Arctic Ocean. It is a simple yet distinctive component of the endemic agglutinated foraminiferal assemblage that colonized the Arctic Ocean after the microfaunal turnover caused by the Paleocene-Eocene Thermal Maximum. Associated foraminifera are characterized by a high percentage of monothalamous species (up to 60 %) and are entirely agglutinated indicating a brackish (mesohaline) early Eocene Arctic Ocean. Hemisphaerammina apta occurs exclusively as individuals attached to fine detrital grains (0.2 to 1.8 mm) of sediment. It is a small species (0.06 to 0.2 mm in diameter), fine-grained, with a low hemispherical profile, no floor across the attachment area, no substantive marginal flange, no internal structures, and no aperture. Lacking an aperture, it apparently propagated and fed through minute (micrometre-sized) interstitial pores in the test wall. Attachment surfaces vary from concave to convex and rough to smooth. Grains for attachment are diverse in shape and type but are predominantly of quartz and chert. The presence of H. apta in the early Eocene was an opportunistic response to an environment with an active hydrological system (storm events). Attachment to grains of sand would provide a more stable base on a sea floor winnowed by storm-generated currents. Active transport is indicated by the relative abundance of reworked foraminifera mixed with in situ species. Contemporaneous reworking and colonization by H. apta is suggested by its attachment to a reworked specimen of Cretaceous foraminifera.

Characterization of the Kootenai River Algae Community and Primary Productivity Before and After Experimental Nutrient Addition, 2004–2007 [Chapter 2, Kootenai River Algal Community Characterization, 2009 KTOI REPORT].

Energy Technology Data Exchange (ETDEWEB)

Holderman, Charlie [Kootenai Tribe of Idaho; Bonners Ferry, ID; Anders, Paul [Cramer Fish Sciences; Moscow, ID; Shafii, Bahman [Statistical Consulting Services; Clarkston, WA

2009-07-01

biological and ecological metrics were used with PCA for diatoms and algae. Algal metrics included a suite of abundance, diversity, richness, dominance, and other measures, whereas additional trophic status and chemical limnology metrics, Van Dam indices and morphological groupings were employed in diatom PCAs. Analysis of Variance (ANOVA) was carried out using chlorophyll metrics and taxa and metric arrays for the diatom and green algae community data for comparing site differences from 2004 through 2007. Clear, statistically significant, biological responses from chlorophyll metrics, and taxa and metrics of the diatom and algal communities were revealed following experimental nutrient addition in the Kootenai River. Chlorophyll metric responses were more often significant and generally greater in magnitude than diatom and green algae taxa and metric responses.

Micro-halocline enabled nutrient recycling may explain extreme Azolla event in the Eocene Arctic Ocean.

Science.gov (United States)

van Kempen, Monique M L; Smolders, Alfons J P; Lamers, Leon P M; Roelofs, Jan G M

2012-01-01

In order to understand the physicochemical mechanisms that could explain the massive growth of Azolla arctica in the Eocene Arctic Ocean, we carried out a laboratory experiment in which we studied the interacting effects of rain and wind on the development of salinity stratification, both in the presence and in the absence of a dense Azolla cover. Additionally, we carried out a mesocosm experiment to get a better understanding of the nutrient cycling within and beneath a dense Azolla cover in both freshwater and brackish water environments. Here we show that Azolla is able to create a windproof, small-scale salinity gradient in brackish waters, which allows for efficient recycling of nutrients. We suggest that this mechanism ensures the maintenance of a large standing biomass in which additional input of nutrients ultimately result in a further expansion of an Azolla cover. As such, it may not only explain the extent of the Azolla event during the Eocene, but also the absence of intact vegetative Azolla remains and the relatively low burial efficiency of organic carbon during this interval.

Micro-halocline enabled nutrient recycling may explain extreme Azolla event in the Eocene Arctic Ocean.

Directory of Open Access Journals (Sweden)

Monique M L van Kempen

Full Text Available In order to understand the physicochemical mechanisms that could explain the massive growth of Azolla arctica in the Eocene Arctic Ocean, we carried out a laboratory experiment in which we studied the interacting effects of rain and wind on the development of salinity stratification, both in the presence and in the absence of a dense Azolla cover. Additionally, we carried out a mesocosm experiment to get a better understanding of the nutrient cycling within and beneath a dense Azolla cover in both freshwater and brackish water environments. Here we show that Azolla is able to create a windproof, small-scale salinity gradient in brackish waters, which allows for efficient recycling of nutrients. We suggest that this mechanism ensures the maintenance of a large standing biomass in which additional input of nutrients ultimately result in a further expansion of an Azolla cover. As such, it may not only explain the extent of the Azolla event during the Eocene, but also the absence of intact vegetative Azolla remains and the relatively low burial efficiency of organic carbon during this interval.

Eocene primates of South America and the African origins of New World monkeys

Science.gov (United States)

Bond, Mariano; Tejedor, Marcelo F.; Campbell, Kenneth E.; Chornogubsky, Laura; Novo, Nelson; Goin, Francisco

2015-04-01

The platyrrhine primates, or New World monkeys, are immigrant mammals whose fossil record comes from Tertiary and Quaternary sediments of South America and the Caribbean Greater Antilles. The time and place of platyrrhine origins are some of the most controversial issues in primate palaeontology, although an African Palaeogene ancestry has been presumed by most primatologists. Until now, the oldest fossil records of New World monkeys have come from Salla, Bolivia, and date to approximately 26 million years ago, or the Late Oligocene epoch. Here we report the discovery of new primates from the ?Late Eocene epoch of Amazonian Peru, which extends the fossil record of primates in South America back approximately 10 million years. The new specimens are important for understanding the origin and early evolution of modern platyrrhine primates because they bear little resemblance to any extinct or living South American primate, but they do bear striking resemblances to Eocene African anthropoids, and our phylogenetic analysis suggests a relationship with African taxa. The discovery of these new primates brings the first appearance datum of caviomorph rodents and primates in South America back into close correspondence, but raises new questions about the timing and means of arrival of these two mammalian groups.

Trace fossils from the eocene Lillebælt clay formation, Røsnæs Peninsula, Denmark

DEFF Research Database (Denmark)

Nielsen, Jan Kresten; Milàn, Jesper; Mesfun, Daniel

2015-01-01

A cliff exposure of the Eocene Lillebælt Clay Formation, on the Røsnæs peninsula of Zealand, Denmark, has yielded a diverse trace-fossil assemblage. The trace fossils are described formally for the first time and assigned to Phymatoderma melvillensis, unnamed clusters of small burrows, Ophiomorpha...

FUNCTIONAL IMPLICATIONS OF A SINGULAR PENGUIN SCAPULA (AVES, SPHENISCIFORMES FROM THE EOCENE OF ANTARCTICA

Directory of Open Access Journals (Sweden)

CAROLINA ACOSTA HOSPITALECHE

2012-11-01

Full Text Available Penguins have peculiar modifications in their skeletal anatomy as a consequence of their extremely specialized diving habit. Morphological specialization is particularly evident in the forelimb. However, the kinematics of the pectoral girdle appears to be key to the locomotion of penguins. Penguin scapulae have an unusual morphology among birds. Modern penguins have a very large (especially broad scapula, whereas this bone is long but narrower in basal fossil species. The recent finding of an incomplete scapula with a singular acromion in the Upper Eocene Submeseta Allomember of the La Meseta Formation in the Antarctic Peninsula reveals a scapula proportionally narrower than those of modern penguins but similar to that of Waimanu and possibly other Eocene species. Osteological comparisons and muscular dissections of modern penguins show that the most striking feature is the curvature of the acromion, and the consequent enlargement of the facies articularis clavicularis. The configuration of the acromion and the corpus scapula reflects a lack of functional optimization in terms of the resistance to forces transverse to the body axis. The scapula´s general morphology suggests it belonged to a medium to large-sized penguin species with no so specialized diving skills. 

Green(ing) infrastructure

CSIR Research Space (South Africa)

Van Wyk, Llewellyn V

2014-03-01

Full Text Available the generation of electricity from renewable sources such as wind, water and solar. Grey infrastructure – In the context of storm water management, grey infrastructure can be thought of as the hard, engineered systems to capture and convey runoff..., pumps, and treatment plants.  Green infrastructure reduces energy demand by reducing the need to collect and transport storm water to a suitable discharge location. In addition, green infrastructure such as green roofs, street trees and increased...

A new burmagomphid dragonfly from the Eocene of Patagonia, Argentina

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Julián F. Petrulevičius

2017-11-01

Full Text Available A new burmagomphid anisopteran, Satelitala soberana gen. et sp. nov. is described from the lower Eocene of Laguna del Hunco, Patagonia, Argentina. The new genus is characterised by hindwing characters such as the subdiscoidal triangle not elongated; anal loop divided longitudinally; paranal cell divided longitudinally; five terminal cells between RP and MA; five terminal cells between MP and CuA; and obtuse angle between PsA and CuP+AA. Burmagomphid dragonflies were represented so far only by one specimen from the middle Cretaceous of Southeast Asia. This new record extends the distribution to Patagonia, to the Cenozoic, and also to paleolake deposits.

The Upper Eocene crustose coralline algal pavement in the Colli Berici, north-eastern Italy

OpenAIRE

Davide Bassi

2005-01-01

A crustose coralline algal pavement, identified in Upper Eocene (Priabonian) shallow water, middleramp carbonates in north-eastern Italy (Colli Berici, Southern Alps), represents a rare example of this facies.The crustose pavement consists of a coralline crust bindstone with a wackestone-packstone matrix, and is characterised by the dominance of crustose coralline thalli composed primarily of melobesioids (Lithothamnion and Mesophyllum) and mastophoroids (Spongites, Lithoporella, Neogoniolith...

Reducing Disparity in Radio-Isotopic and Astrochronology-Based Time Scales of the Late Eocene and Oligocene

NARCIS (Netherlands)

Sahy, Diana; Condon, Daniel J.; Hilgen, Frederik J.|info:eu-repo/dai/nl/102639876; Kuiper, Klaudia F.|info:eu-repo/dai/nl/258125772

2017-01-01

A significant discrepancy of up to 0.6 Myr exists between radio-isotopically calibrated and astronomically tuned time scales of the late Eocene-Oligocene. We explore the possible causes of this discrepancy through the acquisition of “high-precision” 206Pb/238U dating of zircons from 11 volcanic ash

Probabilistic Seismic Hazard Analysis of Victoria, British Columbia, Canada: Considering an Active Leech River Fault

Science.gov (United States)

Kukovica, J.; Molnar, S.; Ghofrani, H.

2017-12-01

The Leech River fault is situated on Vancouver Island near the city of Victoria, British Columbia, Canada. The 60km transpressional reverse fault zone runs east to west along the southern tip of Vancouver Island, dividing the lithologic units of Jurassic-Cretaceous Leech River Complex schists to the north and Eocene Metchosin Formation basalts to the south. This fault system poses a considerable hazard due to its proximity to Victoria and 3 major hydroelectric dams. The Canadian seismic hazard model for the 2015 National Building Code of Canada (NBCC) considered the fault system to be inactive. However, recent paleoseismic evidence suggests there to be at least 2 surface-rupturing events to have exceeded a moment magnitude (M) of 6.5 within the last 15,000 years (Morell et al. 2017). We perform a Probabilistic Seismic Hazard Analysis (PSHA) for the city of Victoria with consideration of the Leech River fault as an active source. A PSHA for Victoria which replicates the 2015 NBCC estimates is accomplished to calibrate our PSHA procedure. The same seismic source zones, magnitude recurrence parameters, and Ground Motion Prediction Equations (GMPEs) are used. We replicate the uniform hazard spectrum for a probability of exceedance of 2% in 50 years for a 500 km radial area around Victoria. An active Leech River fault zone is then added; known length and dip. We are determining magnitude recurrence parameters based on a Gutenberg-Richter relationship for the Leech River fault from various catalogues of the recorded seismicity (M 2-3) within the fault's vicinity and the proposed paleoseismic events. We seek to understand whether inclusion of an active Leech River fault source will significantly increase the probabilistic seismic hazard for Victoria. Morell et al. 2017. Quaternary rupture of a crustal fault beneath Victoria, British Columbia, Canada. GSA Today, 27, doi: 10.1130/GSATG291A.1

Mapping river bathymetry with a small footprint green LiDAR: Applications and challenges

Science.gov (United States)

Kinzel, Paul J.; Legleiter, Carl; Nelson, Jonathan M.

2013-01-01

Airborne bathymetric Light Detection And Ranging (LiDAR) systems designed for coastal and marine surveys are increasingly sought after for high-resolution mapping of fluvial systems. To evaluate the potential utility of bathymetric LiDAR for applications of this kind, we compared detailed surveys collected using wading and sonar techniques with measurements from the United States Geological Survey’s hybrid topographic⁄ bathymetric Experimental Advanced Airborne Research LiDAR (EAARL). These comparisons, based upon data collected from the Trinity and Klamath Rivers, California, and the Colorado River, Colorado, demonstrated

Restore Harlem River's Water Quality to Swimmable/Fishable

Science.gov (United States)

Wang, J.

2014-12-01

Combined sewer overflows (CSOs) discharged untreated sewage into the Harlem River during rainstorms, elevated nutrient and bacteria levels. The river is not safe for swimming, fishing or boating during wet weather conditions. We had collected water samples from CSOs discharge point, analyzed ammonia (NH3-N), phosphate (PO43-), fecal coliform, E.Coli., enteroccus, and polychlorinated biphenyl's (PCBs). On tropical storm Arthur, we had collected CSOs: DO reduced during heavy thunderstorm dropped down from 4 to 2.9 mg/L (49 to 35%); fecal coliform was 5 million MPN/100ml, E.Coli. was 1000-2000 MPN/100ml, enterococcus was 2000-2500 MPN/100ml, turbidity was 882 FAU, ammonia was 2.725 mg/L. Nutrient and bacteria exceeded EPA regulated levels significantly (ammonia: 0.23mg/L; fecal coliform: 200 MPN/100ml, E.Coli.: 126 MPN/100ml, enterococcus: 104 MPN/100ml; turbidity: 0.25-5.25 FAU, DO: 4mg/L). Water sampling of CSOs during heavy rainstorm on 4/30/14 showed turbidity reached 112 FAU, ammonia was 0.839 mg/L, fecal coliform: 5 million MPN/100ml, E.Coli.: 500 MPN/100ml and enterococcus: 10,000 MPN/100ml. CSO collection on June 5, 2014 during morning rainstorm showed ammonia was 2.273 mg/L, turbidity was 37 FAU. New York State Department of Health (NYS DOH) suggested women under 50 & children under 15 do not eat fish such as blue crab meat, carb or lobster tomalley, channel catfish, gizzard shad, white catfish, Atlantic needlefish, bluefish, carp, goldfish, rainbow smelt, striped bass, white perch because chemical concerns (PCBs, cadmium, dioxin). Fish caught in the Harlem River was banned from commercial. Swimming in the river was not safe due to high pathogen levels. CSOs reduction, such as green roof, green wall, and wetland could help reduce stormwater runoff and CSOs. Water quality improvement and ecology restoration will help achieve the goal of swimmable and fishable in the Harlem River.

Update on Kansas City Middle Blue River Green Infrastructure Pilot Project - seminar

Science.gov (United States)

In 2010, Kansas City, MO (KCMO) signed a consent degree with EPA on combined sewer overflows. The City decided to use adaptive management in order to extensively utilize green infrastructure (GI) in lieu of, and in addition to, structural controls. KCMO installed 130 GI storm con...

Spatial coincidence and similar geochemistry of Late Triassic and Eocene-Oligocene magmatism in the Andes of northern Chile: evidence from the MMH porphyry type Cu-Mo deposit, Chuquicamata District

Science.gov (United States)

Zentilli, Marcos; Maksaev, Victor; Boric, Ricardo; Wilson, Jessica

2018-04-01

The MMH porphyry type copper-molybdenum deposit in northern Chile is the newest mine in the Chuquicamata District, one of largest copper concentrations on Earth. Mineralized Eocene-Oligocene porphyry intrusions are hosted by essentially barren Triassic granodiorites. Despite a century of exploitation, geologists still have problems in the mine distinguishing the Triassic granodiorite from the most important ore-carrying Eocene porphyries in the district. To resolve the problem, internally consistent high-quality geochemical analyses of the Triassic and Tertiary intrusives were carried out: explaining the confusion, they show that the rock units in question are nearly identical in composition and thus respond equally to hydrothermal alteration. In detail, the only difference in terms of chemical composition is that the main Eocene-Oligocene porphyries carry relatively less Fe and Ni. Unexpectedly, the mineralized Eocene-Oligocene porphyries have consistently less U and Th than other Tertiary intrusions in the district, a characteristic that may be valuable in exploration. The supergiant copper-molybdenum deposits in the Central Andes were formed within a narrow interval between 45 and 31 Ma, close to 7% of the 200 My duration of "Andean" magmatism, which resulted from subduction of oceanic lithosphere under South America since the Jurassic. Although recent work has shown that subduction was active on the margin since Paleozoic times, pre-Andean (pre-Jurassic) "Gondwanan" magmatism is often described as being very different, having involved crustal melting and the generation of massive peraluminous rhyolites and granites. This study shows that the indistinguishable Late Triassic and Eocene-Oligocene intrusions occupy the same narrow NS geographic belt in northern Chile. If it is accepted that magma character may determine the potential to generate economic Cu-Mo deposits, then Late Triassic volcano-plutonic centres in the same location in the South American margin

Multiproxy record of abrupt sea-surface cooling across the Eocene-Oligocene transition in the Gulf of Mexico

NARCIS (Netherlands)

Wade, B.S.; Houben, A.J.P.; Quaijtaal, W.; Schouten, S.; Rosenthal, Y.; Miller, K.G.; Katz, M.E.; Wright, J.D.; Brinkhuis, H.

2012-01-01

The Eocene-Oligocene transition (EOT; ca. 33–34 Ma) was a time of pronounced climatic change, marked by the establishment of continental-scale Antarctic ice sheets. The timing and extent of temperature change associated with the EOT is controversial. Here we present multiproxy EOT climate records

Oceanographic data collected from Lower Sand Island light (USCG day mark green 5) by Center for Coastal Margin Observation and Prediction (CMOP) and assembled by Northwest Association of Networked Ocean Observation Systems (NANOOS) in the Columbia River Estuary and North East Pacific Ocean from 1997-07-12 to 2014-01-15 (NCEI Accession 0162181)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0162181 contains navigational and physical data collected at Lower Sand Island light (USCG day mark green 5), a fixed station in the Columbia River...

Paralic parasequences associated with Eocene sea-level oscillations in an active margin setting: Trihueco Formation of the Arauco Basin, Chile

Science.gov (United States)

Le Roux, J. P.; Elgueta, Sara

1997-06-01

The Eocene Trihueco Formation is one of the best exposed successions of the Arauco Basin in Chile. It represents a period of marine regression and transgression of second-order duration, during which barrier island complexes developed on a muddy shelf. The strata are arranged in classical shoaling-upward parasequences of shoreface and beach facies capped by coal-bearing, back-barrier lagoon deposits. These fourth-order cycles are superimposed upon third-order cycles which caused landward and seaward shifts of the coastal facies belts. The final, punctuated rise in sea level is represented by shelf mudrocks with transgressive incised shoreface sandstones. Relative sea-level oscillations as revealed in the stratigraphy of the Trihueco Formation show a reasonable correlation with published Eocene eustatic curves.

The Eocene Arctic Azolla phenomenon: species composition, temporal range and geographic extent.

Science.gov (United States)

Collinson, Margaret; Barke, Judith; van der Burgh, Johan; van Konijnenburg-van Cittert, Johanna; Pearce, Martin; Bujak, Jonathan; Brinkhuis, Henk

2010-05-01

Azolla is a free-floating freshwater fern that is renowned for its rapid vegetative spread and invasive biology, being one of the world's fastest growing aquatic macrophytes. Two species of this plant have been shown to have bloomed and reproduced in enormous numbers in the latest Early to earliest Middle Eocene of the Arctic Ocean and North Sea based on samples from IODP cores from the Lomonosov Ridge (Arctic) and from outcrops in Denmark (Collinson et al 2009 a,b Review of Palaeobotany and Palynology 155,1-14; and doi:10.1016/j.revpalbo.2009.12.001). To determine the geographic and temporal extent of this Azolla phenomenon, and the spatial distribution of the different species, we have examined samples from 15 additional sites using material from ODP cores and commercial exploration wells. The sites range from the Sub-Arctic (Northern Alaska and Canadian Beaufort Mackenzie Basin) to the Nordic Seas (Norwegian-Greenland Sea and North Sea Basin). Our data show that the Azolla phenomenon involved at least three species. These are distinguished by characters of the megaspore apparatus (e.g. megaspore wall, floats, filosum) and the microspore massulae (e.g. glochidia fluke tips). The Lomonosov Ridge (Arctic) and Danish occurrences are monotypic but in other sites more than one species co-existed. The attachment to one another and the co-occurrence of megaspore apparatus and microspore massulae, combined with evidence that these spores were shed at the fully mature stage of their life cycle, shows that the Azolla remains were not transported over long distances, a fact which could not be assumed from isolated massula fragments alone. Our evidence, therefore, shows that Azolla plants grew on the ocean surfaces for approximately 1.2 million years (from 49.3 to 48.1 Ma) and that the Azolla phenomenon covered the area from Denmark northwards across the North Sea Basin and the whole of the Arctic and Nordic seas. Apparently, early Middle Eocene Northern Hemisphere middle

Influence of Large Lakes on Methane Greenhouse Forcing in the Early Eocene

Science.gov (United States)

Whiteside, J. H.; Granberg, D. L.; Kasprak, A. H.; Taylor, K. W.; Pancost, R. D.

2011-12-01

Long-duration elevated global temperatures and increased atmospheric pCO2 levels (~1000-2000 ppm) characterized the earliest portion of the Eocene (Ypressian; ~55 to 49 Ma). This extended period of global warmth was also punctuated by a series of short (sub-precessional) hyperthermal events in which atmospheric CO2 (>2000 ppm) and global temperatures rose with unprecedented and (as of yet) unexplained rapidity. This interval is perhaps the best temporal analog for assessing contemporary response of the biosphere and global carbon cycle to increased CO2 emissions. Although these hyperthermals appear paced by 100 Ka and 1 Ma scale orbital (eccentricity) cycles in the marine realm, high frequency forcing processes have not yet been examined, and long continental records have yet to be explored for their expression. To identify sub-eccentricity (Messel Shale, (Darmstadt, Germany.) We demonstrate that in addition to the expected 100 Ka eccentricity cycle, the 40 Ka cycle of obliquity is also an important component of climate variability as reflected in the lacustrine carbon cycle and hence a potential driver of global carbon cycling. We further investigated carbon cycle dynamics by examining biomarker evidence for changes in the terrestrial methane cycle during this time interval. Due to their increased volumes (>60,000 km2), highly stratified and cyclically anoxic lakes of the Eocene could have provided enough methane to alter global radiative forcing. This is consistent with our data, which demonstrate that the GRF and Messel Shale both exhibit strongly reducing conditions as well as abundant methanogen and methanotroph biomarkers. Further, the GRF lacustrine environment was highly stratified with, at times, euxinic waters extending into the photic zone, as inferred from the presence of isorenieratene derivatives. Thus, the GRF was likely an area of elevated methanogenic activity during this time. Increasing input of terrestrial matter into the GRF correlates with

Benthic foraminiferal and isotopic patterns during the Early Eocene Climatic Optimum (Aktulagay section, Kazakhstan)

Science.gov (United States)

Deprez, Arne; Tesseur, Steven; Stassen, Peter; D'haenens, Simon; Steurbaut, Etienne; King, Christopher; Claeys, Philippe; Speijer, Robert P.

2015-04-01

The early Eocene is characterized by long-term global warming culminating in the Early Eocene Climatic Optimum (EECO). During this time interval, the Peri-Tethys was connected to the Arctic and Atlantic Oceans by north-south and east-west trending seaways. The Aktulagay section in Kazakhstan provides an expanded record of the middle Ypresian (NP11-13, ~54-50 Ma; King et al., 2013), including the EECO. The marl sequence features a series of sapropel beds, observed throughout the Peri-Tethys, indicative of basin-wide episodic hypoxic events. In order to unravel paleoenvironmental changes, we carried out quantitative faunal studies and stable isotopic (C, O) investigations on excellently preserved foraminiferal assemblages. The period from 54 to 52.5 Ma (NP11 to lower NP12; Alashen Formation) is characterized by a diverse assemblage of deep outer neritic (~200-250 m) benthic foraminifera, with common Pulsiphonina prima and Paralabamina lunata. The initially (54 Ma) well-ventilated oligo- to mesotrophic seafloor conditions gradually changed to more eutrophic and oxygen-limited. These conditions were more permanent in the sapropel-bearing unit at 52.5-52 Ma (middle NP12; Aktulagay B1 unit). This observation is based on the dominance of Anomalinoides acutus and Bulimina aksuatica and the lower diversity. Also the upward migration of endobenthic species, as suggested by rising δ13Cendobenthic, supports this interpretation. These low-oxygen conditions might have been caused by a transgression, flooding lowlands. Benthic foraminiferal assemblages dominated by Epistominella minuta at ~52-50 Ma (top NP12-NP13; Aktulagay B2 unit) suggest an oligotrophic environment, with transient pulses of phytodetritus. Dinoflagellate blooms and Acarinina isotope values at ~50.5 Ma indicate lower salinity (lower δ18O) and higher productivity (higher δ13C), possibly due to riverine input. Large river plumes, episodically reaching the area, in a monsoonal climate context, might explain this

Eocene Yegua Formation (Claiborne group) and Jackson group lignite deposits of Texas

Science.gov (United States)

Hook, Robert W.; Warwick, Peter D.; Swanson, Sharon M.; Hackley, Paul C.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.

2011-01-01

The lignite deposits within the upper Eocene Yegua Formation (Claiborne Group) and the overlying Jackson Group are among the coal resources that were not quantitatively assessed as part of the U.S. Geological Survey's (USGS) National Coal Resource Assessment (NCRA) program in the Gulf Coastal Plain coal province. In the past, these lignite-bearing stratigraphic units often have been evaluated together because of their geographic and stratigraphic proximity (Fisher, 1963; Kaiser, 1974; Kaiser et al., 1980; Jackson and Garner, 1982; Kaiser, 1996) (Figures 1, 2). The term “Yegua-Jackson trend“ is used informally herein for the lignite-bearing outcrops of these Late Eocene deposits in Texas. Lignite beds in the Yegua-Jackson trend generally are higher both in ash yield and sulfur content than those of the underlying Wilcox Group (Figure 2). Recent studies (Senkayi et al., 1987; Ruppert et al., 1994; Warwick et al., 1996, 1997) have shown that some lignite beds within the Yegua-Jackson trend contain partings of volcanic ash and host elevated levels of trace elements that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Amendments of 1990. Lignite beds within the Yegua Formation are thin (less than or equal to 6 ft) and laterally discontinuous in comparison with most Wilcox Group deposits (Ayers, 1989a); in contrast, the Jackson Group lignite beds range up to 12 ft in total thickness and are relatively continuous laterally, extending nearly 32 mi along strike.

Customers’ Intention to Use Green Products: the Impact of Green Brand Dimensions and Green Perceived Value

Directory of Open Access Journals (Sweden)

Doszhanov Aibek

2015-01-01

Full Text Available This study aimed to identify the relationships between green brand dimension (green brand awareness, green brand image, and green brand trust, green perceived value and customer’s intention to use green products. Data was collected through structured survey questionnaire from 384 customers of three hypermarkets in Kuala-Lumpur. Data was analyzed based on multiple regression analysis. The results indicate that there are significant relationships between green brand awareness, green brand trust, green perceived value, and customer’s intention to use green products. However, green brand image was not found to have significant relationship with customer’s intention to use green products. The discussion presented suggestions for marketers and researchers interested in green branding.

Cretaceous and Eocene Adakites in the Sikhote-Alin area (Russian Far East) and their correlation with adakitic rocks in the East Asia continental margin

Science.gov (United States)

Wu, T. J.; Jahn, B. M.

2017-12-01

Adakitic rocks of the Sikhote-Alin area were emplaced during two main periods: the Cretaceous (132-98 Ma) and Eocene (46-39 Ma). These rocks primarily occur in the Khanka Block and, less commonly, in the Sikhote-Alin Orogenic Belt. The adakitic rocks record the following chemical compositions: SiO2 = 57-74%, Al2O3 = 15-18%, Na2O = 3.5-6.1%, K2O = 0.7-3.2%, Na2O/K2O = 1.1-3.9, Sr/Y = 33-145, and (La/Yb)N = 11-53. The HREE and HFSE in these rocks are remarkably depleted. The Early Cretaceous adakites record ɛNd(T) = -1.0 to +3.2 and ISr = 0.7040-0.7090, and the Eocene adakitic rocks record Nd(T) = -2.0 to +2.2 and ISr = 0.7042-0.7058. Adakitic features suggest different modes of magma generation; a comparison of the Sr/Y and La/Yb ratios and geochemical data on Harker diagrams between the two periods of adakitic rocks reveals differences in their petrogenesis. The Cretaceous adakites may have been generated by the partial melting of meta-basic rocks in a subduction zone, accompanied by the emplacement of volcanic arc granitoids. Therefore, the subduction of the Paleo-Pacific Plate beneath the Sikhote-Alin was probably initiated during this time. The Eocene rocks, which record increasing adakitic features with increasing silica content, are most likely the product of andesite that underwent fractionation of mineral assemblage including clinopyoxene, orthopyroxene, garnet and amphibole. These rocks and associated basalts and rhyolite were formed after Cretaceous arc magmatism in the Sikhote-Alin area and were most likely generated by rollback of the subducting Pacific Plate after the Eocene. Abundant adakitic granitoids of Early Cretaceous and Eocene age occur in the Kitakami and Abukuma Mountains of NE Japan. Consequently, it is highly probable that a geological correlation existed between Sikhote-Alin and North Japan, particularly before the opening of the Japan Sea.

Agerinia marandati sp. nov., a new early Eocene primate from the Iberian Peninsula, sheds new light on the evolution of the genus Agerinia.

Science.gov (United States)

Femenias-Gual, Joan; Minwer-Barakat, Raef; Marigó, Judit; Poyatos-Moré, Miquel; Moyà-Solà, Salvador

2017-01-01

The Eocene was the warmest epoch of the Cenozoic and recorded the appearance of several orders of modern mammals, including the first occurrence of Euprimates. During the Eocene, Euprimates were mainly represented by two groups, adapiforms and omomyiforms, which reached great abundance and diversity in the Northern Hemisphere. Despite this relative abundance, the record of early Eocene primates from the European continent is still scarce and poorly known, preventing the observation of clear morphological trends in the evolution of the group and the establishment of phylogenetic relationships among different lineages. However, knowledge about the early Eocene primates from the Iberian Peninsula has been recently increased through the description of new material of the genus Agerinia from several fossil sites from Northeastern Spain. Here we present the first detailed study of the euprimate material from the locality of Masia de l'Hereuet (early Eocene, NE Spain). The described remains consist of one fragment of mandible and 15 isolated teeth. This work provides detailed descriptions, accurate measurements, high-resolution figures and thorough comparisons with other species of Agerinia as well with other Eurasian notharctids. Furthermore, the position of the different species of Agerinia has been tested with two phylogenetic analyses. The new material from Masia de l'Hereuet shows several traits that were previously unknown for the genus Agerinia, such as the morphology of the upper and lower fourth deciduous premolars and the P 2 , and the unfused mandible. Moreover, this material clearly differs from the other described species of Agerinia , A. roselli and A. smithorum , thus allowing the erection of the new species Agerinia marandati . The phylogenetic analyses place the three species of Agerinia in a single clade, in which A. smithorum is the most primitive species of this genus. The morphology of the upper molars reinforces the distinction of Agerinia from

Monitoring and Evaluation of Environmental Flow Prescriptions for Five Demonstration Sites of the Sustainable Rivers Project

Science.gov (United States)

Konrad, Christopher P.

2010-01-01

The Nature Conservancy has been working with U.S. Army Corps of Engineers (Corps) through the Sustainable Rivers Project (SRP) to modify operations of dams to achieve ecological objectives in addition to meeting the authorized purposes of the dams. Modifications to dam operations are specified in terms of environmental flow prescriptions that quantify the magnitude, duration, frequency, and seasonal timing of releases to achieve specific ecological outcomes. Outcomes of environmental flow prescriptions implemented from 2002 to 2008 have been monitored and evaluated at demonstration sites in five rivers: Green River, Kentucky; Savannah River, Georgia/South Carolina; Bill Williams River, Arizona; Big Cypress Creek, Texas; and Middle Fork Willamette River, Oregon. Monitoring and evaluation have been accomplished through collaborative partnerships of federal and state agencies, universities, and nongovernmental organizations.

The Influence of Proactive Green Innovation and Reactive Green Innovation on Green Product Development Performance: The Mediation Role of Green Creativity

OpenAIRE

Yu-Shan Chen; Tai-Wei Chang; Chun-Yu Lin; Pi-Yu Lai; Kuan-Hung Wang

2016-01-01

This study fills the research gap in the exploration of the relationships between both proactive and reactive green innovations and green product development performance, and examines the mediating effect of green creativity. Structural equation modeling (SEM) is utilized to test the hypotheses. From the sample of 146 valid respondents, the results show that proactive green innovation positively affects green creativity and green product development performance, and green creativity positivel...

Preliminary study of the oil shales of the Green River formation in the tri-state area of Colorado, Utah, and Wyoming to investigate their utility for disposal of radioactive waste

International Nuclear Information System (INIS)

1975-05-01

Results are presented of a preliminary study of the oil shales of the Green River formation in the tri-state area of Colorado, Utah, and Wyoming to investigate their utility for possible disposal of radioactive waste material. The objective of this study was to make a preliminary investigation and to obtain a broad overview of the physical and economic factors which would have an effect on the suitability of the oil shale formations for possible disposal of radioactive waste material. These physical and economic factors are discussed in sections on magnitude of the oil shales, waste disposal relations with oil mining, cavities requirements, hydrological aspects, and study requirements

Floods of July 23-26, 2010, in the Little Maquoketa River and Maquoketa River Basins, Northeast Iowa

Science.gov (United States)

Eash, David A.

2012-01-01

Minor flooding occurred July 23, 2010, in the Little Maquoketa River Basin and major flooding occurred July 23–26, 2010, in the Maquoketa River Basin in northeast Iowa following severe thunderstorm activity over the region during July 22–24. A breach of the Lake Delhi Dam on July 24 aggravated flooding on the Maquoketa River. Rain gages at Manchester and Strawberry Point, Iowa, recorded 72-hour-rainfall amounts of 7.33 and 12.23 inches, respectively, on July 24. The majority of the rainfall occurred during a 48-hour period. Within the Little Maquoketa River Basin, a peak-discharge estimate of 19,000 cubic feet per second (annual flood-probability estimate of 4 to 10 percent) at the discontinued 05414500 Little Maquoketa River near Durango, Iowa streamgage on July 23 is the sixth largest flood on record. Within the Maquoketa River Basin, peak discharges of 26,600 cubic feet per second (annual flood-probability estimate of 0.2 to 1 percent) at the 05416900 Maquoketa River at Manchester, Iowa streamgage on July 24, and of 25,000 cubic feet per second (annual flood-probability estimate of 1 to 2 percent) at the 05418400 North Fork Maquoketa River near Fulton, Iowa streamgage on July 24 are the largest floods on record for these sites. A peak discharge affected by the Lake Delhi Dam breach on July 24 at the 05418500 Maquoketa River near Maquoketa, Iowa streamgage, located downstream of Lake Delhi, of 46,000 cubic feet per second on July 26 is the third highest on record. High-water marks were measured at five locations along the Little Maquoketa and North Fork Little Maquoketa Rivers between U.S. Highway 52 near Dubuque and County Road Y21 near Rickardsville, a distance of 19 river miles. Highwater marks were measured at 28 locations along the Maquoketa River between U.S. Highway 52 near Green Island and State Highway 187 near Arlington, a distance of 142 river miles. High-water marks were measured at 13 locations along the North Fork Maquoketa River between

Paleomagnetism and the Alpine tectonics of Eurasia IV : Jurassic, Cretaceous and Eocene pole positions from northeastern Turkey

NARCIS (Netherlands)

Voo, R. van der

In April 1965 and May 1966 several groups of samples were collected by the author in northern and eastern Turkey in view of a study of their magnetic properties. The characteristic magnetizations of four groups of Eocene and Cretaceous volcanic rocks and sediments had the following directions of

Metaphysical green

DEFF Research Database (Denmark)

Earon, Ofri

2011-01-01

to adapt to urban environment. It explores the potential of Sensation of Green in the city. The paper questions whether the Sensation of Green could introduce a new spectrum of greens, beside the real green. It develops the term of metaphysical green – does green have to be green or can it be only...

Scale insect larvae preserved in vertebrate coprolites (Le Quesnoy, France, Lower Eocene): paleoecological insights.

Science.gov (United States)

Robin, Ninon; Foldi, Imre; Godinot, Marc; Petit, Gilles

2016-10-01

Coprolites of terrestrial vertebrates from the Sparnacian Le Quesnoy locality (Ypresian, Eocene, MP7, 53 Ma; Oise, France) were examined for possible parasitic helminth eggs. The extraction of the coprolite components was performed by a weak acetolyse and a slide mounting in glycerin. This long examination did not reveal paleoparasite remains, which may be explained through several arguments. However, some pollen grains, some enigmatic components, and two well-preserved first-instar cochineal nymphs (Hemiptera: Sternorrhyncha: Coccoidea) were evidenced in coprolites. Identified as Coccidae, these larvae are the earliest stage of the scale insect development ever reported as fossil, revealing the specific environment of preservation that fossilized scats may provide. These observations, combined to the coprolites morphotype, enable to ascribe the fossil scats producer to a small herbivorous mammal present in the deposit (early perissodactyls or Plesiadapidae). Regarding the ecology of extant representatives of Coccidae, this mammal was a likely foliage consumer, and the abundant Juglandaceae and/or Tiliaceae from Le Quesnoy might have lived parasitized by scale insects. These Early Eocene parasites had an already well-established dissemination strategy, with prevalent minute first-instar larvae. The herein performed extraction technique appears well-suited for the study of carbonate coprolites and could certainly be useful for evidencing other kind of microorganisms (including internal parasites).

Early evidence of xeromorphy in angiosperms: stomatal encryption in a new eocene species of Banksia (Proteaceae) from Western Australia.

Science.gov (United States)

Carpenter, Raymond J; McLoughlin, Stephen; Hill, Robert S; McNamara, Kenneth J; Jordan, Gregory John

2014-09-01

• Globally, the origins of xeromorphic traits in modern angiosperm lineages are obscure but are thought to be linked to the early Neogene onset of seasonally arid climates. Stomatal encryption is a xeromorphic trait that is prominent in Banksia, an archetypal genus centered in one of the world's most diverse ecosystems, the ancient infertile landscape of Mediterranean-climate southwestern Australia.• We describe Banksia paleocrypta, a sclerophyllous species with encrypted stomata from silcretes of the Walebing and Kojonup regions of southwestern Australia dated as Late Eocene.• Banksia paleocrypta shows evidence of foliar xeromorphy ∼20 Ma before the widely accepted timing for the onset of aridity in Australia. Species of Banksia subgenus Banksia with very similar leaves are extant in southwestern Australia. The conditions required for silcrete formation infer fluctuating water tables and climatic seasonality in southwestern Australia in the Eocene, and seasonality is supported by the paucity of angiosperm closed-forest elements among the fossil taxa preserved with B. paleocrypta. However, climates in the region during the Eocene are unlikely to have experienced seasons as hot and dry as present-day summers.• The presence of B. paleocrypta within the center of diversity of subgenus Banksia in edaphically ancient southwestern Australia is consistent with the continuous presence of this lineage in the region for ≥40 Ma, a testament to the success of increasingly xeromorphic traits in Banksia over an interval in which numerous other lineages became extinct. © 2014 Botanical Society of America, Inc.

The effect of maturation on the configurations of acyclic isoprenoid acids in sediments

Science.gov (United States)

Mackenzie, A. S.; Patience, R. L.; Yon, D. A.; Maxwell, J. R.

1982-05-01

Within a variety of sedimentary rocks of differing maturity, the configurations of a suite of acyclic isoprenoid acids have been examined by gas Chromatographic (in a few cases also by combined gas chromatography-mass spectrometry) analysis of their diastereoisomeric methyl and (-)-menthyl esters. The samples include the Eocene Messel (Germany) and Green River (U.S.) shales, the Permian Irati shale (Brazil) and a number of Lower Toarcian shales from the Paris Basin. The isomer distributions show that isomerisation occurs at the chiral centres with increasing maturation (to increase the number of isomers) and that the rate of isomerisation increases for centres (C-2,C-3) closest to the carboxyl group. These results suggest that adsorption of the carboxyl group to a catalyst surface may control the isomerisation rates by way of access to the catalyst.

A new mechanism for the two-step d18O signal at the Eocene-Oligocene boundary

NARCIS (Netherlands)

Tigchelaar, M.; von der Heydt, A.S.; Dijkstra, H.A.

2011-01-01

The most marked step in the global climate transition from “Greenhouse” to “Icehouse” Earth occurred at the Eocene-Oligocene (E-O) boundary, 33.7 Ma. Evidence for climatic changes comes from many sources, including the marine benthic 18O record, showing an increase by 1.2– 1.5‰ at this time. This

Xenoliths in Eocene lavas from Central Tibet record carbonated metasomatism of the lithosphere

Science.gov (United States)

Goussin, Fanny; Cordier, Carole; Boulvais, Philippe; Guillot, Stéphane; Roperch, Pierrick; Replumaz, Anne

2017-04-01

Cenozoic post-collisional volcanism of the Tibetan Plateau, emplaced on an accreted continental margin under compression, could bring important information regarding the edification of the Plateau. In this study, we combined petrography, whole rock geochemistry, stable isotopes and in situ mineral analysis to decipher the genesis of Eocene-Oligocene magmatic rocks from the Nangqian basin (35-38 Ma, [Spurlin et al., 2005; Xu et al., 2016]), located at the hinge between Central Tibet and the Eastern Indo-Asia Collision Zone. Our dataset includes potassic trachyandesites; amphibole-bearing potassic trachytes; and rare ultrapotassic (K2O/Na2O ≥ 4) mafic syenites. All samples have high REE abundances (La = 100 - 500 x primitive mantle). Fractionation of heavy REE (Gd/YbN > 3) indicates melting in the garnet stability field, and relative depletion in high-field strength elements (Nb, Ta) indicates a selective enrichment of the source by metasomatic fluids. This metasomatism event is also evidenced by the occurrence of re-equilibrated mantle xenocrysts of phlogopite (Mg# = 88 - 90 and Cr2O3 content = 0.9 - 1.82 wt%) in mafic syenites. Potassic trachyandesites have specific composition, with negative Zr-Hf anomaly and low Hf/Sm (0.2 - 0.4). Indeed, they include xenocrystic aggregates, composed of magmatic clinopyroxene, apatite and subordinate biotite and feldspar, with interstitial calcite and dolomite. δ18OV -SMOW (9.2 - 11.0 ) and δ13CV -PDB (-6.1 - -4.0 ) of these rocks indicate the presence of primary, mantle-derived carbonates. In situ analysis of the major and trace element compositions of the carbonates, clinopyroxenes and apatites further suggest that these aggregates represent cumulates of a carbonate-bearing magma. These xenoliths thus show that the lithospheric mantle was also metasomatized by CO2-rich fluids. Cenozoic carbonatites in China have been identified in Maoniuping in Western Sichuan (31.7 Ma), Lixian in the Western Qinlin (22-23 Ma), and

Goulds Belt, Interstellar Clouds, and the Eocene Oligocene Helium-3 Enhancement

Science.gov (United States)

Rubincam, David Parry

2015-01-01

Drag from hydrogen in the interstellar cloud which formed Gould's Belt may have sent interplanetary dust particle (IDPs) and small meteoroids with embedded helium to the Earth, perhaps explaining part the helium-3 flux increase seen in the sedimentary record near the Eocene-Oligocene transition. Assuming the Solar System passed through part of the cloud, IDPs in the inner Solar System may have been dragged to Earth, while dust and small meteoroids in the asteroid belt up to centimeter size may have been dragged to the resonances, where their orbital eccentricities were pumped up into Earth-crossing orbits; however, this hypotheses does not explain the Popigai and Chesapeake Bay impacts.

Neogene palaeochannel deposits in Sudan - Remnants of a trans-Saharan river system?

Science.gov (United States)

Bussert, Robert; Eisawi, Ali A. M.; Hamed, Basher; Babikir, Ibrahim A. A.

2018-05-01

The start of Nile-type trans-Saharan drainage systems in NE Africa during the Cenozoic is disputed. Stratigraphical and sedimentological data in Egypt are partly in conflict with the uplift history of potential source areas of water and sediment in East Africa. Here, we investigate outcrops of the Wadi Awatib Conglomerate in Sudan that provide the first evidence of northerly flowing Neogene rivers in the region. Dimension and relief of basal erosion surfaces, overall geometry of deposits and palaeocurrent indicators demonstrate that the deposits represent the fill of northward-oriented incised valleys. The conglomerates were deposited in deep gravel-bed rivers, by hyperconcentrated flows, tractions carpets and gravel bars, primarily during heavily sediment-laden floods of probably monsoonal origin. Stratigraphical and geomorphological relationships show that the deposits are between Eocene and Pliocene in age. Considering the structural history of the region and periods in the Cenozoic with palaeoclimatic conditions suitable for the production and transport of gravels, we hypothesize that the dramatic base-level fall during the Late Miocene Messinian salinity crisis in combination with a favorable palaeoclimate caused the incision of valleys and their subsequent filling with conglomerates. Sea-level change in the Mediterranean Sea and headward erosion of streams that were connected to the Egyptian Nile might have been the primary cause of valley incision and deposition of conglomerates, despite a location far inland from the coastline. We suggest that the deposits document a relatively young Neogene (Messinian to early Pliocene) trans-Saharan river system unrelated to uplift of the Ethiopian Plateau.

Metre-scale cyclicity in Middle Eocene platform carbonates in northern Egypt: Implications for facies development and sequence stratigraphy

Science.gov (United States)

Tawfik, Mohamed; El-Sorogy, Abdelbaset; Moussa, Mahmoud

2016-07-01

The shallow-water carbonates of the Middle Eocene in northern Egypt represent a Tethyan reef-rimmed carbonate platform with bedded inner-platform facies. Based on extensive micro- and biofacies documentation, five lithofacies associations were defined and their respective depositional environments were interpreted. Investigated sections were subdivided into three third-order sequences, named S1, S2 and S3. Sequence S1 is interpreted to correspond to the Lutetian, S2 corresponds to the Late Lutetian and Early Bartonian, and S3 represents the Late Bartonian. Each of the three sequences was further subdivided into fourth-order cycle sets and fifth-order cycles. The complete hierarchy of cycles can be correlated along 190 km across the study area, and highlighting a general "layer-cake" stratigraphic architecture. The documentation of the studied outcrops may contribute to the better regional understanding of the Middle Eocene formations in northern Egypt and to Tethyan pericratonic carbonate models in general.

The Influence of Environmental Friendliness on Green Trust: The Mediation Effects of Green Satisfaction and Green Perceived Quality

Directory of Open Access Journals (Sweden)

Yu-Shan Chen

2015-07-01

Full Text Available As global green trends became more prevalent, green marketing also developed into an important issue. Although prior literature explored the main factors affecting green trust, it was inconclusive as to how environmental friendliness could affect the green trust in green marketing. This study aims to focus on the positive influence of environmental friendliness on green trust, and explore the mediation effects of green satisfaction and green perceived quality. This study undertakes an empirical study by means of questionnaire survey. The respondents are consumers who have experience purchasing green products. This study applies structural equation modeling (SEM to test the hypotheses. The findings of this study indicate that (1 environmental friendliness has a significant positive impact on green satisfaction, green perceived quality, and green trust; (2 both green satisfaction and green perceived quality positively affect green trust; and (3 green satisfaction and green perceived quality partially mediate the positive relationship between environmental friendliness and green trust.

Green power certification: environmental and consumer protection benefits of the Green-e programme

Energy Technology Data Exchange (ETDEWEB)

Wingate, M.; Hamrin, J. [Center for Resource Solutions (United States); Rabago, K. [Rocky Mountain Inst. (United States); Wiser, R. [Lawrence Berkeley National Lab. (United States)

2000-06-01

This article gives details of the Green-e environmental certification programme which certifies electricity generated from renewable energy sources in the US. This first non-profit certification programme originally was set up for California, and has now spread to other regions. The objectives of the Green-e programme, the need for the electricity product to meet minimum criteria to qualify, marketer requirements, verification of product claims, administration of the programme, and the second year programme results are discussed. The way in which the Green-e programme fits in with other programmes such as those set up by the state and federal customer protection agencies to help consumers select environmentally superior power is described.

Apatite fission-track evidence of widespread Eocene heating and exhumation in the Yukon-Tanana Upland, interior Alaska

Science.gov (United States)

Dusel-Bacon, C.; Murphy, J.M.

2001-01-01

We present an apatite fission-track (AFT) study of five plutonic rocks and seven metamorphic rocks across 310 km of the Yukon-Tanana Upland in east-central Alaska. Samples yielding ???40 Ma AFT ages and mean confined track lengths > 14 ??m with low standard deviations cooled rapidly from >120??C to 40 Ma suggest partial annealing and, therefore, lower maximum temperatures (???90-105??C). A few samples with single-grain ages of ???20 Ma apparently remained above ???50??C after initial cooling. Although the present geothermal gradient in the western Yukon-Tanana Upland is ???32??C/km, it could have been as high as 45??C/km during a widespread Eocene intraplate magmatic episode. Prior to rapid exhumation, samples with ???40 Ma AFT ages were >3.8-2.7 km deep and samples with >50 Ma AFT ages were >3.3-2.0 km deep. We calculate a 440-320 m/Ma minimum rate for exhumation of all samples during rapid cooling. Our AFT data, and data from rocks north of Fairbanks and from the Eielson deep test hole, indicate up to 3 km of post-40 Ma vertical displacement along known and inferred northeast-trending high-angle faults. The predominance of 40-50 Ma AFT ages throughout the Yukon-Tanana Upland indicates that, prior to the post-40 Ma relative uplift along some northeast-trending faults, rapid regional cooling and exhumation closely followed the Eocene extensional magmatism. We propose that Eocene magmatism and exhumation were somehow related to plate movements that produced regional-scale oroclinal rotation, northward translation of outboard terranes, major dextral strike-slip faulting, and subduction of an oceanic spreading ridge along the southern margin of Alaska.

Whence the beardogs? Reappraisal of the Middle to Late Eocene 'Miacis' from Texas, USA, and the origin of Amphicyonidae (Mammalia, Carnivora).

Science.gov (United States)

Tomiya, Susumu; Tseng, Zhijie Jack

2016-10-01

The Middle to Late Eocene sediments of Texas have yielded a wealth of fossil material that offers a rare window on a diverse and highly endemic mammalian fauna from that time in the southern part of North America. These faunal data are particularly significant because the narrative of mammalian evolution in the Paleogene of North America has traditionally been dominated by taxa that are known from higher latitudes, primarily in the Rocky Mountain and northern Great Plains regions. Here we report on the affinities of two peculiar carnivoraforms from the Chambers Tuff of Trans-Pecos, Texas, that were first described 30 years ago as Miacis cognitus and M. australis . Re-examination of previously described specimens and their inclusion in a cladistic analysis revealed the two taxa to be diminutive basal amphicyonids; as such, they are assigned to new genera Gustafsonia and Angelarctocyon , respectively. These two taxa fill in some of the morphological gaps between the earliest-known amphicyonid genus, Daphoenus , and other Middle-Eocene carnivoraforms, and lend additional support for a basal caniform position of the beardogs outside the Canoidea. The amphicyonid lineage had evidently given rise to at least five rather distinct forms by the end of the Middle Eocene. Their precise geographical origin remains uncertain, but it is plausible that southern North America served as an important stage for a very early phase of amphicyonid radiation.

Radioecological monitoring of the Tom' river ecosystem within zone of nuclear fuel cycle plants influence

International Nuclear Information System (INIS)

Leonova, G.A.; Bobrov, V.A.; Malikov, Yu.I.; Mel'gunov, M.S.; Makarova, I.V.; Toropov, A.V.

2005-01-01

According to the results of 2000-2002 expeditions the estimation of radioactive contamination scales in water ecosystems within zone of Siberian Chemical Industrial Complex (SCC) influence was performed. The accumulation levels of short-lived artificial radionuclides in biota components of SCC technological channel (Romashka river), and spatial radionuclide distribution in biota of ecosystem of the Tom' and Ob' rivers at different distances from the local source have been determined using biochemical indication method. The most frequently occurring species of plants, filamentous green algae and fish were selected as indicator bioobjects for the monitoring. In spectrum of radioisotopes revealed in water plants, fish and water of the Romashka river there were determined twelve short-living isotopes that denoted continuing river burial. (author)

The freshwater fern Azolla (Azollaceae) from Eocene Arctic and Nordic Sea sediments: New species and their stratigraphic distribution

NARCIS (Netherlands)

van der Burgh, J.; Collinson, M.E.; van Konijnenburg-van Cittert, J.H.A.; Barke, J.; Brinkhuis, H.

2013-01-01

Three new species of the freshwater fern Azolla are described from Eocene marine deposits of the Arctic and Nordic seas, bringing the total number of species now documented from these areas to five. Azolla arctica Collinson et al., Azolla jutlandica Collinson et al., Azolla nova sp. nov. and Azolla

Upstream factors affecting Tualatin River algae—Tracking the 2008 Anabaena algae bloom to Wapato Lake, Oregon

Science.gov (United States)

Rounds, Stewart A.; Carpenter, Kurt D.; Fesler, Kristel J.; Dorsey, Jessica L.

2015-12-17

Significant Findings A large bloom that included floating mats of the blue-green algae Anabaena flos-aquae occurred in the lower 20 miles of the Tualatin River in northwestern Oregon between July 7 and July 17, 2008.

Eocene antiquity of the European nyctitheriid euarchontan mammal Darbonetus

Directory of Open Access Journals (Sweden)

Jerry J. Hooker

2018-06-01

Full Text Available Until now Darbonetus was represented by only one valid species, the type species D. aubrelongensis from the early Oligocene of the Quercy region, France. A late appearance of this genus and of its closest relative Amphidozotherium have been thought to result from dispersal from outside western Europe, rather than a local ancestry earlier in the late Eocene. Here, a new species, Darbonetus sigei sp. nov., is described from the middle Priabonian site of La Débruge, France. Although clearly closely related to D. aubrelongensis, D. sigei shows less reduction of its p2, p3, and m3 than in the more derived type species. The early age of D. sigei suggests that its origins were within the still isolated central European island and that it is unnecessary to invoke dispersal from another continent.

Algal-mediated ecosystem exchanges in the Eel River drainage network: towards photogrammetric mapping of color to function

Science.gov (United States)

Power, M. E.; Welter, J.; Furey, P.; Lowe, R.; Finlay, J. C.; Hondzo, M.; Limm, M.; Bode, C.; Dietrich, W. E.

2009-12-01

Seasonal algal proliferations in river networks are typically short-lived (weeks-months) but spatially extensive. They mediate important ecological and biogeochemical exchanges within and between ecosystems. We are investigating correspondence of assemblage color with ecosystem function in the nitrogen-limited Eel River of northern California. During summer base flow following winter floods, Eel algal assemblages are dominated by the green macroalga Cladophora glomerata. New growths are green, but blooms turn yellow as Cladophora filaments are colonized by epiphytic diatoms (Cocconeis spp.). Later, proliferations turn rust colored as epiphytic assemblages became dominated by Epithemia spp., diatoms that contain nitrogen-fixing cyanobacterial endosymbionts. Epithemia-encrusted Cladophora occurs at and downstream of reaches draining > 100 km2 (where summer inundated average channel widths > 25 m), coinciding with a threshold increase in concentration of total dissolved nitrogen. Areal nitrogen fixation rates are 14x higher in rusty algal proliferations than in green, and 3-4x higher than in yellow Cladophora mats. Corresponding increases in insect emergence suggest that nitrogen fixed by cyanobacterial endosymbionts is highly edible. Rates of biomass emergence from rusty Cladophora mats are 12-17 times greater than from green mats, and 8-10 times greater from rusty than from yellow Cladophora mats, because larger taxa emerge from rusty mats (Chironominae versus Ceratopogonidae in yellow mats). Photogrammetric detection of spatial coverage and color changes in algal proliferations may help us track nitrogen fluxes they mediate (riverine loading from the atmosphere via fixation, river to the watershed return via insect emergence) that link riverine to aerial, watershed, and potentially nearshore marine ecosystems at reach to basin scales.

The green building envelope : Vertical greening

NARCIS (Netherlands)

Ottelé, M.

2011-01-01

Planting on roofs and façades is one of the most innovative and fastest developing fields of green technologies with respect to the built environment and horticulture. This thesis is focused on vertical greening of structures and to the multi-scale benefits of vegetation. Vertical green can improve

Cenozoic tectono-thermal history of the Tordrillo Mountains, Alaska: Paleocene-Eocene ridge subduction, decreasing relief, and late Neogene faulting

Science.gov (United States)

Benowitz, Jeff A.; Haeussler, Peter J.; Layer, Paul W.; O'Sullivan, Paul B.; Wallace, Wes K.; Gillis, Robert J.

2012-01-01

Topographic development inboard of the continental margin is a predicted response to ridge subduction. New thermochronology results from the western Alaska Range document ridge subduction related orogenesis. K-feldspar thermochronology (KFAT) of bedrock samples from the Tordrillo Mountains in the western Alaska Range complement existing U-Pb, 40Ar/39Ar and AFT (apatite fission track) data to provide constraints on Paleocene pluton emplacement, and cooling as well as Late Eocene to Miocene vertical movements and exhumation along fault-bounded blocks. Based on the KFAT analysis we infer rapid exhumation-related cooling during the Eocene in the Tordrillo Mountains. Our KFAT cooling ages are coeval with deposition of clastic sediments in the Cook Inlet, Matanuska Valley and Tanana basins, which reflect high-energy depositional environments. The Tordrillo Mountains KFAT cooling ages are also the same as cooling ages in the Iliamna Lake region, the Kichatna Mountains of the western Alaska Range, and Mt. Logan in the Wrangell-St. Elias Mountains, thus rapid cooling at this time encompasses a broad region inboard of, and parallel to, the continental margin extending for several hundred kilometers. We infer these cooling events and deposition of clastic rocks are related to thermal effects that track the eastward passage of a slab window in Paleocene-Eocene time related to the subduction of the proposed Resurrection-Kula spreading ridge. In addition, we conclude that the reconstructed KFATmax negative age-elevation relationship is likely related to a long period of decreasing relief in the Tordrillo Mountains.

Geochemical and geological control on filling history of Eocene reservoirs, Maracaibo Basin, Venezuela

Energy Technology Data Exchange (ETDEWEB)

Alberdi, M.; Maguregui, J.; Toro, C.; Marquina, M. [Intevep S.A., Caracas (Venezuela)

1996-08-01

Crude oils of Eocene fluvio-deltaic reservoirs in {open_quotes}Bloque V{close_quotes} and {open_quotes}Centro Lago{close_quotes} fields in the center of the Maracaibo Lake show many differences in composition, which are due to stratigraphically and structurally controlled reservoir geometry and a low rate of in-reservoir mixing of at least two successive petroleum charges. Oils produced from the top of structural highs contain 18(H) oleanane, higher Pr/Ph and C{sub 23-3}/C{sub 24-4} ratios, a lower proportion of DBT/P compounds, and clearly different fingerprint patterns in the C{sub 6}-C{sub 15} range, than those observed in oils produced from the lower parts of the structures. These compositional differences suggest that two source rocks, or two distinctive organic facies within the same Cretaceous La Luna Formation, generated and filled vertically poorly connected Eocene reservoirs. On the other hand, saturate-biomarkers ratios, triaromatics (C{sub 21}/C{sub 21}+C{sub 28}), n-paraffins (n-C{sub 20}/n-C{sub 29}) and n-heptane index suggest that oils in upper reservoirs are slightly less mature than oils in lower reservoirs and, consequently filled the structure first. Additional evidence from formation water analysis and tectonic basin evolution allow us to interpret at least two petroleum pulses from Cretaceous source rocks during Upper Miocene to present day kitchens located in the Andes foredeep at the southeast of the study area.

Analysis of the urban green areas of Nicosia: the case study of Linear Park of Pedieos River

Science.gov (United States)

Zanos, Pavlos; Georgi, Julia

2017-09-01

At present, the need for creating outdoor green areas is unquestionable. Their value is shown through their use for recreation, sports, cultural and socioeconomic purposes, the ecology and especially biodiversity, which has always been considered as one of the most important factors in recent years, as well as in the future. With the creation of new parks and open green spaces, the legacy will be continued for the next generations, with designs that will be pleasantly utilized through the years. In the first part of this study, we examined the way the largest urban green spaces in Nicosia affect and contribute to the lifestyle of the inhabitants of the city, as well as the reasons why the citizens of Cyprus embraced urban parks in their everyday life, making them so popular. The present paper, therefore, analyses both the effect and the changes in the urban structure while urban green spaces in the city of Nicosia are being created, as well as which areas are affected, how they are affected and to what extent. We have conducted a field-based survey, providing the urban parks' visitors with questionnaires. This enabled us to draw a wealth of essential conclusions concerning the visitors' preferences. We have also listed both the positive and negative impacts of urban green spaces on both the economic and urban design sectors, as well as on Cypriots' recreation time. The green areas of Nicosia, along with their detailed analysis, are extensively presented in this study. Moreover, in the second part of this study, the G.I.S program was used to create a space presentation of the urban linear park of Pedieos, where the area was mapped and the positive and negative elements of the park were analysed. In this part, ways to address the emerging issues are also proposed.

GREEN MANAGEMENT: THE REALITY OF BEING GREEN IN BUSINESS

OpenAIRE

Tran, Ben

2009-01-01

Green management and going green are not as clear cut and easy as hyped by the general media. While going ecologically green is indeed beneficial and appropriate, the process and procedure of becoming green is anything but easy. Firstly, turning green is largely not a legal requirement, but a voluntary process. Thus, even though LEED (which is by far the more publicly known green certification standard) governs the certification of the green management effort, it is not a compulsory condition...

Urban River Restoration in Tehran: Challenges and Opportunities

Science.gov (United States)

Azizi, S.; Mousavi, H.; Farshad, F.; Hoseinzade Vahedi, N.; Zanjanian, M.; Khamesi, A.; Shojaee, M.; Safdarnejad, S. M.; Mirrahimi, H.; Ahmari, N.

2015-12-01

The typical treatment of urban river streams in Tehran has been limited channelization over the last 30 years. Changes in stream hydrology resulting from urbanization causes a widening gap between river and neighborhoods that results in the ecological and visual division between built and natural environments. To address these problems, a new management perspective in Tehran municipality seeks creating a sequence of thematic green spaces which serve as meeting points for adjacent neighborhoods. Implementation of pilot projects has proved that restoration of urban rivers requires a holistic approach with a range of technologies and tools that contribute to the goal of integrated planning. Currently, our team is working on Darband and Darabad catchments in north east Tehran,to provide opportunities for restoration of natural life in order to improve the amenity, ecology and sustainability of an urban river environment based on 4 key planning principles of: Demonstrating characteristics of the city's unique relationship to the river in the riverfront design; Knowing the river ecosystem and planning for a scale larger than the river front; minimizing new floodplain development; and Providing public access, connections, and recreational uses. This presentation will discuss the process of developing a new integrated GIS-based catchment planning system which helped the City shape its strategic plan for two catchments for the 2015-2030 period through multi-objective and multi-criteria optimization. The strategic plan is expected to enable the city to project the effects of introducing any future development in the catchment area on the river system, helping it to prevent such development activities which can have unintended long-term impacts.

Computational modeling of river flow using bathymetry collected with an experimental, water-penetrating, green LiDAR

Science.gov (United States)

Kinzel, P. J.; Legleiter, C. J.; Nelson, J. M.

2009-12-01

Airborne bathymetric Light Detection and Ranging (LiDAR) systems designed for coastal and marine surveys are increasingly being deployed in fluvial environments. While the adaptation of this technology to rivers and streams would appear to be straightforward, currently technical challenges remain with regard to achieving high levels of vertical accuracy and precision when mapping bathymetry in shallow fluvial settings. Collectively these mapping errors have a direct bearing on hydraulic model predictions made using these data. We compared channel surveys conducted along the Platte River, Nebraska, and the Trinity River, California, using conventional ground-based methods with those made with the hybrid topographic/bathymetric Experimental Advanced Airborne Research LiDAR (EAARL). In the turbid and braided Platte River, a bathymetric-waveform processing algorithm was shown to enhance the definition of thalweg channels over a more simplified, first-surface waveform processing algorithm. Consequently flow simulations using data processed with the shallow bathymetric algorithm resulted in improved prediction of wetted area relative to the first-surface algorithm, when compared to the wetted area in concurrent aerial imagery. However, when compared to using conventionally collected data for flow modeling, the inundation extent was over predicted with the EAARL topography due to higher bed elevations measured by the LiDAR. In the relatively clear, meandering Trinity River, bathymetric processing algorithms were capable of defining a 3 meter deep pool. However, a similar bias in depth measurement was observed, with the LiDAR measuring the elevation of the river bottom above its actual position, resulting in a predicted water surface higher than that measured by field data. This contribution addresses the challenge of making bathymetric measurements with the EAARL in different environmental conditions encountered in fluvial settings, explores technical issues related to

Comparison of benthos and plankton for selected areas of concern and non-areas of concern in western Lake Michigan Rivers and Harbors in 2012

Science.gov (United States)

Eikenberry, Barbara C. Scudder; Bell, Amanda H.; Olds, Hayley T.; Burns, Daniel J.

2016-07-25

Recent data are lacking to assess whether impairments still exist at four of Wisconsin’s largest Lake Michigan harbors that were designated as Areas of Concern (AOCs) in the late 1980s due to sediment contamination and multiple Beneficial Use Impairments (BUIs), such as those affecting benthos (macroinvertebrates) and plankton (zooplankton and phytoplankton) communities. During three seasonal sampling events (“seasons”) in May through August 2012, the U.S. Geological Survey collected sediment benthos and water plankton at the four AOCs as well as six less-degraded non-AOCs along the western Lake Michigan shoreline to assess whether AOC communities were degraded in comparison to non-AOC communities. The four AOCs are the Lower Menominee River, the Lower Green Bay and Fox River, the Sheboygan River, and the Milwaukee Estuary. Due to their size and complexity, multiple locations or “subsites” were sampled within the Lower Green Bay and Fox River AOC (Lower Green Bay, the Fox River near Allouez, and the Fox River near De Pere) and within the Milwaukee Estuary AOC (the Milwaukee River, the Menomonee River, and the Milwaukee Harbor) and single locations were sampled at the other AOCs and non-AOCs. The six non-AOCs are the Escanaba River in Michigan, and the Oconto River, Ahnapee River, Kewaunee River, Manitowoc River, and Root River in Wisconsin. Benthos samples were collected by using Hester-Dendy artificial substrates deployed for 30 days and by using a dredge sampler; zooplankton were collected by net and phytoplankton by whole-water sampler. Except for the Lower Green Bay and Milwaukee Harbor locations, communities at each AOC were compared to all non-AOCs as a group and to paired non-AOCs using taxa relative abundances and metrics, including richness, diversity, and an Index of Biotic Integrity (IBI, for Hester-Dendy samples only). Benthos samples collected during one or more seasons were rated as degraded for at least one metric at all AOCs. In the

Inducement of heterochronic variation in a species of planktic foraminifera by a Late Eocene impact event

Science.gov (United States)

Macleod, N.; Kitchell, J. A.

1988-01-01

While it is well known that the cosmic impact event at or near the Cretaceous-Tertiary boundary coincides with an interval of mass extinction, a similar impact (or series of impacts) near the Eocene-Oligocene boundary presents a more complex picture, in terms of associated fluctuations in marine biotic diversity. Tektites, microtektites, and mineral grains exhibiting features of shock metamorphism found in Eocene sediments of the western N. Atlantic, Caribbean, and Gulf of Mexico (comprising the North American microtektite strewn field) offer compelling evidence for a catastrophic impact event. Despite the magnitude of this event, however, few extinctions in the planktic marine fauna are known to have occurred coincident with this event. Instead, changes in relative abundance, morphology, and development occurred. Cosmic impacts generally have been interpreted as influencing the course of evolution through the wholesale elimination of significant portions of standing biotic diversity. Indeed, extinction traditionally has been viewed as the negative side of evolution. In some instances, it is suggested such impact events can serve instead to increase, rather than decrease, morphological and ecological diversity, by altering the developmental programs within species at the level of the local population.

Heterogeneity in global vegetation and terrestrial climate change during the late Eocene to early Oligocene transition.

Science.gov (United States)

Pound, Matthew J; Salzmann, Ulrich

2017-02-24

Rapid global cooling at the Eocene - Oligocene Transition (EOT), ~33.9-33.5 Ma, is widely considered to mark the onset of the modern icehouse world. A large and rapid drop in atmospheric pCO 2 has been proposed as the driving force behind extinctions in the marine realm and glaciation on Antarctica. However, the global terrestrial response to this cooling is uncertain. Here we present the first global vegetation and terrestrial temperature reconstructions for the EOT. Using an extensive palynological dataset, that has been statistically grouped into palaeo-biomes, we show a more transitional nature of terrestrial climate change by indicating a spatial and temporal heterogeneity of vegetation change at the EOT in both hemispheres. The reconstructed terrestrial temperatures show for many regions a cooling that started well before the EOT and continued into the Early Oligocene. We conclude that the heterogeneous pattern of global vegetation change has been controlled by a combination of multiple forcings, such as tectonics, sea-level fall and long-term decline in greenhouse gas concentrations during the late Eocene to early Oligocene, and does not represent a single response to a rapid decline in atmospheric pCO 2 at the EOT.

An unusual new species of Hallodapomimus Herczek, 2000 from the Eocene Baltic amber (Hemiptera, Heteroptera, Miridae, Phylinae

Directory of Open Access Journals (Sweden)

Aleksander Herczek

2015-03-01

Full Text Available Hallodapomimus antennatus sp. n. (Hemiptera: Heteroptera, Miridae, Phylinae, Hallodapini is described from a macropterous female found in Eocene Baltic amber. The new species can be recognized readily from the other species of the genus, mainly due to its unusual second antennal segment. A key for the identification of all known fossil Hallodapini is presented.

Global warming and ocean acidification through halted weathering feedback during the Middle Eocene Climatic Optimum