Results 61 to 70 of about 46,126 (273)

Evidence From Microscopy and U–Pb Geochronology as a Clue to the Influence of the Cretaceous Magmatism in the Diagenesis of Pre‐Salt Carbonate Reservoirs in the Santos Basin (Brazil)

Geological Journal, EarlyView.
Carbonates from Santos Basin revealed U–Pb ages correlated with basalt ages (A), suggesting that they were formed during magmatic events. These events placed hot CO2 in the reservoir, which, when mixed with carbonate‐rich cold water (B), led to thermal convection, enabling the formation of the U contained in the carbonates.
Marco António Ruivo de Castro e Brito, Cristiano Leite Sombra, Davy Raeder Brandão, Cleverson Guizan Silva, Sidney Luiz de Matos Mello, Eugênio Vaz dos Santos Neto, Rui Jorge Fernandes Baptista, Ramsés Capilla, Luiz Antônio Pierantoni Gambôa   +8 more
wiley   +1 more source

Geophysical characterization of black shales

Proceedings, 2012
Black shales are dark, thinly bedded sedimentary rocks deposited under anaerobic conditions. They are rich in carbon, sulfides and organic matter, and potentially can serve as hydrocarbon source rocks. Black shales may also contain significant enrichments of gas or oil (gas shales, oil shales).
Bauer, K., Streich, R., Adao, F., Bauman-Wilke, M., Ritter, O., Schovsbo, N., Spangenberg, E., Stiller, M.   +7 more
openaire   +3 more sources

The relationship between cellular protein content and selenium accumulation in freshwater microalgae

Integrated Environmental Assessment and Management, EarlyView.
Abstract Variability in the bioconcentration of selenium (Se) by primary producers at the base of the food web results in uncertainty in predictions of bioaccumulation and ecological risk to higher trophic level organisms. Water chemistry, speciation of Se, and periphyton community composition have all been suggested as factors that contribute to ...
Courtney Bogstie, Melanie Gallant, James R. Elphick, Christopher Kennedy   +3 more
wiley   +1 more source

Forecasting Natural Gas Prices in Real Time

Journal of Applied Econometrics, EarlyView.
ABSTRACT This paper provides a comprehensive analysis of the forecastability of the real price of natural gas in the United States at the monthly frequency considering a universe of models that differ in complexity and economic content. We find that considerable reductions in mean‐squared prediction error relative to a no‐change benchmark can be ...
Christiane Baumeister, Florian Huber, Thomas K. Lee, Francesco Ravazzolo   +3 more
wiley   +1 more source

Selenium and molybdenum enrichment in uranium roll-front deposits of Wyoming and Colorado, USA [PDF]

, 2017
Acknowledgements The authors wish to thank Cal VanHolland, Jim Bonner and John Cooper of Ur-Energy (Casper, Wyoming) for their assistance with sampling, data provision and feedback.
Bullock, Liam A., Parnell, John
core   +1 more source

A low‐cost, automated, and adaptable system for field‐based measurement of pCO2, pCH4, and associated variables in groundwater

Limnology and Oceanography: Methods, EarlyView.
Abstract The Groundwater Automated Chemical Examiner (GrACE) is an automated analytical system of integrated sensors for the field‐based measurement of chemical and physical properties of groundwater. The GrACE system was designed to explore parameters influencing the dissolved concentrations of carbon dioxide (pCO2) and methane (pCH4) in groundwater ...
Madeline McChesney Every, Jesse T. Dugan, John D. Kessler   +2 more
wiley   +1 more source

Mid-Cretaceous paleoenvironmental changes in the western Tethys [PDF]

Climate of the Past, 2018
We present a continuous record of surface water temperature and fertility variations through the latest Barremian–Cenomanian interval (ca. 27 Myr) based on calcareous nannofossil abundances from the western Tethys.
C. Bottini, E. Erba
doaj   +1 more source

Anisotropy in Fracking: A Percolation Model for Observed Microseismicity

, 2014
Hydraulic fracturing (fracking) using high pressures and a low viscosity fluid allow the extraction of large quantiles of oil and gas from very low permeability shale formations.
Norris, J. Quinn, Rundle, John B., Turcotte, Donald L.   +2 more
core   +1 more source

An in situ shelly fauna from the lower Paleozoic Zapla diamictite of northwestern Argentina: implications for the age of glacial events across Gondwana [PDF]

, 2015
A shelly fauna from the upper part of the Zapla glacial diamictite includes thelingulate brachiopod Orbiculoidea radiata Troedsson, the rhynchonelliforms Dalmanella cf. testudinaria (Dalman) and Paromalomena sp., the bivalve Modiolopsis?
Benedetto, Juan Luis Arnaldo, de la Puente, Graciela Susana, Halpern, Karen, Monaldi, Cesar Ruben   +3 more
core   +2 more sources

Iowa Population Exposures to Metals and Metalloids in Well Water

Environmental Toxicology, EarlyView.
ABSTRACT Previous Iowa studies suggest low levels and chronic arsenic exposures are associated with prostate cancer. The rural Iowa population heavily relies on private wells for drinking water resources and thus is vulnerable to contaminants such as heavy metals found in well water.
Donald L. Simmons, Brian Wels, Alyssa Mattson, Elizabeth M. Miller, Zachary E. Hoggarth, Maya Sternberg, Susie Y. Dai, Dustin May, Michael Schueller, Michael Pentella   +9 more
wiley   +1 more source