Results 51 to 60 of about 9,511 (218)

Sedimentary facies and stacking patterns of fluvio‐deltaic and ‐estuarine deposits from the Palaeoarchean Moodies Group in the Stolzburg Syncline (Barberton Greenstone Belt, South Africa)

The Depositional Record, Volume 12, Issue 4, September 2026.
Drillcore BASE‐5B from the Stolzburg Syncline, Barberton Greenstone Belt, reveals a coarsening‐upward, river‐dominated fluvio‐deltaic succession transitioning upward to a fining‐upward, tide‐dominated‐estuarine succession. Abstract Investigating fluvio‐marine depositional environments from early geological times is of great importance, as they provide ...
Sanway Mukhopadhyay, Dennis Schreiber, Nina Wichern, David De Vleeschouwer, Christoph Heubeck, Marcello Gugliotta   +5 more
wiley   +1 more source

Pelagic barite precipitation at micromolar ambient sulfate

Nature Communications, 2017
The question of how significant barite deposits were able to form from early Earth’s low-sulfate seas remains controversial. Here, the authors show pelagic barite precipitation within a strongly barite-undersaturated ecosystem, highlighting the ...
Tristan J. Horner, Helena V. Pryer, Sune G. Nielsen, Peter W. Crockford, Julia M. Gauglitz, Boswell A. Wing, Richard D. Ricketts   +6 more
doaj   +1 more source

Evaluation of Barium Sulfate (Barite) Solubility Using Different Chelating Agents at a High Temperature [PDF]

Journal of Petroleum Science and Technology, 2017
Barium sulfate (barite) is one of the widely used weighting materials in the preparation of drilling fluid for deep oil and gas wells. Barite is not soluble in the regular solvents; such as, hydrochloric acid (HCl) and other acids.
BADR BA GERI, Mohamed Mahmoud, Reyad Shawabkeh, Abdulazeez Abdulraheem   +3 more
doaj   +1 more source

Uranium Isotope Evidence for Persistent Global Ocean Anoxia Across the Ediacaran–Cambrian Transition in Siberia

Geobiology, Volume 24, Issue 5, September/October 2026.
ABSTRACT The enigmatic Ediacara biota represents Earth's earliest example of macroscopic, complex life, yet the driving forces promoting their mid‐Ediacaran evolution and subsequent extinction across the Ediacaran–Cambrian boundary remain speculative. If these were true animals requiring oxygen for aerobic respiration, their rise has often been linked ...
Andrew D. Doerrler, Tian Gan, Geoffrey J. Gilleaudeau, Matthew G. Pedersen, Natalia Bykova, Vasiliy Marusin, Natalia A. Ivanova, Boris Kochnev, Dimitriy V. Grazhdankin, Karel Kletetschka, Alan J. Kaufman   +10 more
wiley   +1 more source

Monte carlo assessment of advanced shielding materials for space‐efficient radiotherapy vault design

Journal of Applied Clinical Medical Physics, Volume 27, Issue 8, August 2026.
Abstract Background Conventional radiotherapy vault shielding typically employs 2 to 3 meters of ordinary concrete, consistent with NCRP Report 151 reference data. While NCRP 151 specifies dose‐based design goals rather than mandating particular materials, the practical default of concrete results in vault footprints of 150 to 200 m2 per linac, which ...
Beechui Koo, Richard Xu, Morgan Glennie, Jungwook Shin, Karl Farrey, Siyong Kim, James J. Sohn   +6 more
wiley   +1 more source

ENRICHMENT OF MASSIVE SULFIDES FROM THE SEMENOV HYDROTHERMAL CLUSTER (MID-ATLANTIC RIDGE) IN BARITE: A RESULT OF E-MORB INVOLVEMENT AND MAGMATIC CONTRIBUTION [PDF]

Минералогия
The paper reviews and compares the barite findings in hydrothermal fields of the midoceanic ridges. The genetic significance of barite is considered for the Semenov hydrothermal sulfide cluster associated with an oceanic core complex (OCC) at 13°30′ N of
I.Yu. Melekestseva, G.A. Tret’yakov, V.E. Beltenev   +2 more
doaj   +1 more source

Carbonate‐Associated Sulfate Does Not Record Superheavy δ34S in Deep Scandinavian Bedrock Fractures: Implications for Pyrite Formation in the Deep Biosphere

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract In deep bedrock fractures of the Fennoscandian shield, pyrite with “superheavy” δ34S values of up to 147‰ exists together with calcite. The extreme variability and 34S‐enrichment in pyrite indicate that microbial sulfate reduction (MSR) evolved to almost complete sulfate exhaustion in closed‐system microenvironments.
V. Fichtner, F. Genske, E. Kooijman, H. Drake   +3 more
wiley   +1 more source

Barite in northern Llano County [PDF]

, 1941
This report gives the results of a study of barite deposits on the adjoining Freeman and Hillsmeier properties in northern Llano County, where a small tonnage of residual barite has been mined or "gophered" during recent years.
Zapp, Alfred D.
core   +1 more source

Glacial‐Interglacial Shifts in Export Productivity and Iron Flux in the Indian Sector of the Southern Ocean

Paleoceanography and Paleoclimatology, Volume 41, Issue 8, August 2026.
Abstract Greater ocean export productivity fueled by enhanced delivery of iron to the Sub‐Antarctic Zone (SAZ) of the Southern Ocean is hypothesized to play an important role in reducing atmospheric CO2 during Pleistocene glaciations. However, spatial variability in iron input and nutrient availability complicates quantifying the integrated impact of ...
Joseph C. Cresswell, Zanna Chase, Taryn Noble, Thomas Williams, Dawn Herweynen, Francesco Muschitiello, George Rowland, Ashley T. Townsend, Natalie Umling, Mirko Uy, Lena Thöle, Helen E. Amsler, Samuel L. Jaccard, Melissa A. Berke, Elisabeth L. Sikes   +14 more
wiley   +1 more source

The Formation of Barite and Celestite through the Replacement of Gypsum [PDF]

, 2020
Barite (BaSO4) and celestite (SrSO4) are the end-members of a nearly ideal solid solution. Most of the exploitable deposits of celestite occur associated with evaporitic sediments which consist of gypsum (CaSO4·2H2O) or anhydrite (CaSO4). Barite, despite
Pablo Forjanes, Forjanes Pérez, Pablo Cayetano, Lurdes Fernández-Díaz, Fernández Díaz, María Lourdes, Astilleros García-Monge, José Manuel, José Astilleros   +5 more
core   +1 more source