Results 61 to 70 of about 8,930 (209)

Photochemical effects of Mars‐like UV irradiation on carboxylic acids in carbonaceous chondrites and expectations for abiotic background organics on Mars

Meteoritics &Planetary Science, Volume 61, Issue 10, Page 2445-2465, October 2026.
Abstract In the search for life on Mars, understanding the origin of preserved organics is critical. Expected sources include exogenous delivery, endogenous synthesis, and potentially life. Environmental processing by ultraviolet (UV) irradiation can alter these organics, obscuring hallmarks of their origin. To deconvolve these effects, we conducted an
D. K. Buckner, J. C. Aponte, A. C. Schuerger, D. I. Foustoukos, F. Seguin, M. B. Wilhelm, G. Cooper, A. J. Williams   +7 more
wiley   +1 more source

Porosity Preservation in Deeply Buried (8500 m) Jurassic Calcareous Mudstones of the Vienna Basin (Austria)

Terra Nova, Volume 38, Issue 5, Page 306-313, October 2026.
ABSTRACT Significant porosity of more than 5% was found at depths of more than 8500 m in poorly sorted, calcareous mudstones of the Malmian Mikulov Formation. These overpressured rocks are the main hydrocarbon source rock in the Vienna Basin. Core samples from present‐day depths of 8150 m to 8550 m were analysed using X‐ray diffraction and scanning ...
Susanne Gier, Jürgen Schieber, Andrea Forstner‐Schicker, Peter Krois   +3 more
wiley   +1 more source

Relationship between Hydrocarbon Gas Generation and Kerogen Structural Evolution Revealed by Closed System Pyrolysis and Quantitative Py-GC Analysis of a Type II Kerogen

, 2021
Kerogen can release both liquid and gaseous hydrocarbons during thermal maturation. In this study, the maturation and hydrocarbon generation of a low-maturity type II kerogen were simulated via temperature-programmed gold tube closed system (GTCS ...
Chunqing Jiang, Zheng, Yijun, Yuhong Liao, Yijun Zheng, Liao, Yuhong, Jiang, Chunqing   +5 more
core   +1 more source

Biosignature Preservation in Stromatolites From the Carri Laufquen Lakes System, Patagonia: Implications for Martian Palaeolacustrine Environments

Geobiology, Volume 24, Issue 5, September/October 2026.
ABSTRACT The Carri Laufquen Lakes System is a highly alkaline, basalt‐hosted lacustrine environment in northern Patagonia, Argentina. Diverse morphologies of Late Pleistocene sub‐fossil stromatolites occur along the lakeshores. Using detailed optical and electron microscopy, spectroscopy and organic geochemical analyses, this study shows that ...
Victor Amir Cardoso Dorneles, Maëva Millan, Fernando J. Gómez, Primož Šket, Jens Najorka, Cindy Broderick, Wren Montgomery, Barbara Cavalazzi, Keyron Hickman‐Lewis   +8 more
wiley   +1 more source

Kerogen-rich shales and coals: Key drivers of microbial life and carbon cycling in the deep biosphere

DNA sequence data of DNA from kerogens after microbial enrichment. These data are for sequences of bacteria inhabiting laboratory microcosms of kerogens inoculated with a lab culture. They are sequences associated with incoulation of four primary kerogen
Cockell, Charles, Waajen, Annemiek
core   +1 more source

Surface Chemistry and Atomic-Scale Reconstruction of Kerogen-Silica Composites

, 2014
The interest in gas shale, a novel source rock of natural gas, has tremendously increased in recent years. Better understanding of the kerogen/rock interaction is of crucial importance for efficient gas extraction and hence for asset management.
Ulm, F.J., Cordeiro, M.N.D.S., Hantal, G., Pellenq, R.J.M., Brochard, Laurent   +4 more
core   +3 more sources

Mechanism of adsorption-desorption hysteresis of shale gas in kerogen and influencing factors analysis

Youqi dizhi yu caishoulu
The adsorption behavior of methane in kerogen is of great significance for shale gas reserve evaluation and production prediction. However， there is still a lack of clear understanding of the hysteresis phenomenon and its micro-causes in the process of ...
TANG Haijun, QIU Xingdong, LIU Yisheng, DAI Xia, TANG Cong, HUANG Liang, WANG Lei   +6 more
doaj   +1 more source

Raman Line Scan Analyses and a New Hypothesis for the Formation of Anatase‐Hosting Microbialites: Study of the Stromatolites From Saint‐Jean‐de‐la‐Rivière, Cotentin, France

Journal of Raman Spectroscopy, Volume 57, Issue 8, Page 1463-1480, August 2026.
Micrometer analysis of millimeter lines of Raman spectra concludes in the association of anatase and graphitized organic matter (graphogen). The photosynthetic microorganisms at the origin of the microbialites produce O2, which is transformed by TiO2 into reactive species that, in turn, decompose the organic matter of the microorganisms. ABSTRACT Raman
Marie‐Paule Bassez
wiley   +1 more source

The Constructions and Pyrolysis of 3D Kerogen Macromolecular Models: Experiments and Simulations

Global Challenges, 2019
Kerogens are extracted from deep shales to study pyrolysis of deep shale samples. The 2D molecular models of kerogens are obtained by a series of physical and chemical experiments by which the macromolecular models of kerogens are constructed.
XiaoHe Wang, XianFu Huang, Kui Lin, Ya‐Pu Zhao   +3 more
doaj   +1 more source

The Ames impact structure, Oklahoma: New radioisotopic constraints and implications for North American impact chronology

Meteoritics &Planetary Science, Volume 61, Issue 8, Page 2103-2139, August 2026.
Abstract The Ames impact structure (Oklahoma) is thought to have formed during the Ordovician Meteor Event, based on conodont biostratigraphy of its crater fill. Here, U–Pb zircon dates from its impact‐melt portion, conducted using secondary ion mass spectrometry and laser ablation–inductively coupled plasma–mass spectrometry (n = 37 spots), yield a ...
Elizabeth J. Catlos, Andrew F. Parisi, Michael E. Brookfield, Timmons Erickson, Sean P.S. Gulick, Axel K. Schmitt, Daniel F. Stockli, Daniel P. Miggins, Ben Ruchte, Mark Cloos   +9 more
wiley   +1 more source