Results 91 to 100 of about 29,167 (235)

In Situ Detection of Opal‐A in Jezero Crater, Mars

Journal of Geophysical Research: Planets, Volume 131, Issue 5, May 2026.
Abstract We report the in situ detection of amorphous hydrated silica in the Bills Bay abrasion patch, located in the eastern portion of the Margin Unit between the rim of Jezero crater and the western delta. Here, hydrated silica co‐occurs with olivine, Fe‐Mg carbonates, secondary Fe‐Mg silicates, and hydrated Mg‐sulfate as determined by UV Raman ...
Sergei V. Bykov, Kenneth H. Williford, Anushree Srivastava, Andrew Steele, Linda C. Kah, Travis A. Olds, Sunanda Sharma, Richard V. Morris, Kimberly Poppy Sinclair, Ryan S. Jakubek, Nikole C. Haney, Francis M. McCubbin, Mariek E. Schmidt, Ashley E. Murphy, Sandra Siljeström, Eva L. Scheller, William Abbey, Sanford A. Asher, Kevin P. Hand, Kyle Uckert, Jeffrey T. Osterhout, Carina Lee, Rohit Bhartia, Michelle E. Minitti, Joanna V. Clark, Patrick Casbeer, Shiv K. Sharma   +26 more
wiley   +1 more source

Towards OWL-based Knowledge Representation in Petrology

, 2011
This paper presents our work on development of OWL-driven systems for formal representation and reasoning about terminological knowledge and facts in petrology.
Kudryavtsev, Dmitry, Ryakhovsky, Vladimir, Shkotin, Alex   +2 more
core  

Mineralogical Characterization of the Lunar South Polar Region: 2. Exploring Mafic‐Bearing Targets With Optimized Traverse Paths at Mons Kocher

Journal of Geophysical Research: Planets, Volume 131, Issue 5, May 2026.
Abstract Several national space agencies and commercial entities are currently targeting the Moon's south polar region for human and robotic exploration. Of particular interest are materials excavated and ejected from the Moon's largest and oldest impact structure, the South Pole‐Aitken Basin (SPA), as these ancient materials are a window into the ...
D. P. Moriarty III, N. E. Petro, B. A. Cohen   +2 more
wiley   +1 more source

Peridotite weathering is the missing ingredient of Earth’s continental crust composition

Nature Communications, 2018
The concentration of Ni and Cr of the continental crust cannot be explained by formation models involving differentiated magmatic rocks. Here, the authors show that hydrothermal alteration and chemical weathering of ultramafic rock compensates for the ...
Andreas Beinlich, Håkon Austrheim, Vasileios Mavromatis, Ben Grguric, Christine V. Putnis, Andrew Putnis   +5 more
doaj   +1 more source

A mid-Archaean ophiolite complex, Barberton Mountain land [PDF]

New field observations and structurally restored geologic sections through the southern part of 3.5-3.6 Ga Barberton greenstone belt show that its mafic to ultramafic rocks form a pseudostratigraphy comparable to that of Phanerozoic ophiolites; this ...
Dewit, M. J., Hart, R., Hart, R.
core   +1 more source

Hydromagnesite Precipitation in an Ultramafic‐Hosted Alkaline Lake: Insights From Lake Salda for Jezero Crater, Mars

Journal of Geophysical Research: Planets, Volume 131, Issue 5, May 2026.
Abstract Lake Salda (SW Turkey) is one of the most compelling terrestrial analogs for Jezero Crater on Mars due to its highly alkaline, Mg‐rich waters and hydromagnesite‐forming microbialites. This study integrates hydrochemical measurements, saturation‐index modeling, SEM–TEM imaging, and X‐ray diffraction (XRD) analysis to disentangle the biotic and ...
Mirosław Słowakiewicz, Mario Borrelli, Gürçay Kıvanç Akyıldız, Marek Szczerba, Ezher Tagliasacchi, Edoardo Perri   +5 more
wiley   +1 more source

Percolation of Dioritic Melts Through Ultramafic Cumulate Mushes Forms High‐Mg Intermediate Igneous Rocks

Geophysical Research Letters
Percolation of dioritic melts through ultramafic cumulate mushes and their reaction and hybridization have been documented in some arcs, but the impact of the processes on the compositions of arc igneous rocks is not yet fully understood.
Wei Xu, Qing Wang, Roberto F. Weinberg, Di‐Cheng Zhu, Shi‐Hong Tian   +4 more
doaj   +1 more source

Mineralised ultramafic rocks in South Greenland

Rapport Grønlands Geologiske Undersøgelse, 1971
In 1960 several mineralised ultramafic boulders with a remarkable content of Pt were found by M. Loretan in the neighbourhood of Sarqa fjord in the Nanortalik district, South Greenland. This stimulated interest in a closer examination of the mafic and ultramafic rocks of South Greenland and in 1962 and 1963 J. P.
openaire   +2 more sources

Putative Analogs of Pyrite Suns Forming in Proglacial Alaska Mudflats

Journal of Geophysical Research: Biogeosciences, Volume 131, Issue 5, May 2026.
Abstract Disc‐shaped pyrite suns of the Pennsylvanian age Anna Shale are thought to have formed where pressure restricted pyrite crystal growth to a flattened disc shape during diagenesis at the Anna Shale and the underlying Herrin coal boundary.
Heather L. Fair, Trinity L. Hamilton, Jeff R. Havig   +2 more
wiley   +1 more source

Quantitative chemical analyses of rocks with X-ray fluorescence analyzer: (1) Major elements

Antarctic Record, 1995
Analytical procedures for major elements in rocks (Si, Ti, Al, Fe, Mn, Mg, Ca, Na, K, P), using a newly installed X-ray fluorescence analyzer (RIGAKURIX3000) at the National Institute of Polar Research, are summarized.
Yoichi Motoyoshi, Kazuyuki Shiraishi
doaj   +1 more source