Results 61 to 70 of about 2,355 (221)

Talc‐Tempered Pottery From Bala Hissar, Kabul: An Analytical Study

Archaeometry, EarlyView.
ABSTRACT Potsherds of cooking ware excavated at Bala Hissar archaeological site in Kabul were studied using X‐ray fluorescence (XRF), scanning electron microscope‐energy dispersive X‐ray spectrometry (SEM‐EDS), Raman spectroscopy, X‐ray powder diffraction (XRPD), thermogravimetric analysis (TGA) and optical microscopy.
Parviz Holakooei, Babak Rafiei‐Alavi, Hafizullah Hazim, Hasti Pezeshkanjalili, Lara Maritan   +4 more
wiley   +1 more source

Mechanisms of Uranium and Thorium Accumulation in the Lower Ediacaran Marine Sediments from the Upper Yangtze Platform, China: Implications for Helium Exploration

Journal of Marine Science and Engineering
The ocean is a significant global reservoir of uranium (U) and thorium (Th). These elements can be incorporated into marine sediments through processes involving organic matter (OM), redox conditions, terrigenous inputs, and mineral interactions.
Yi Zou, Qingyong Luo, Huayao Zou, Jianfa Chen, Wenming Ji, Jin Wu, Tao Du, Xintong Liu, Zilong Fang, Wenxin Hu, Ye Zhang, Jinqi Qiao   +11 more
doaj   +1 more source

The Toarcian black shale event in northern Italy

Organic Geochemistry, 1988
Abstract During the Early Toarcian (Jurassic; c . 192 Ma), organic-rich sediments were deposited in many areas of Europe. This paper reports the major findings of the first part of an organic geochemical investigation of the Toarcian Oceanic Anoxic Event (OAE).
Farrimond, P, Eglinton, G, Brassell, S, Jenkyns, H   +3 more
openaire   +2 more sources

Lodge moraines: a common yet underreported end‐moraine type—a review

Boreas, EarlyView.
Lodge moraines are a distinct genetic type of end moraine formed by submarginal accretion of subglacial till; they are some of the largest end moraines in the world. Although underreported in the literature, they are of equal importance to push, dump and hummocky end moraines. End moraines are formed at glacier ice margins and show the extent of former
Mark D. Johnson, Jose Luis Antinao, Ívar Örn Benediktsson, David A. Grimley, Carrie E. Jennings, Henry M. Loope, Tom V. Lowell, David M. Mickelson, Peter L. Moore, Thomas A. Nash, J. Elmo Rawling III, Jamey Stutz   +11 more
wiley   +1 more source

Depositional processes of varved sediments from proglacial Lago Frías since 1800 CE (North Patagonian Andes, Argentina)

Boreas, EarlyView.
The glacierized Valle Frías in Northern Patagonia is one of the best‐studied valleys in South America and includes varved sediments from Lago Frías. We complement this lacustrine record with a high‐resolution documentation of varve counts and their composition.
Bernd Zolitschka, Philipp Böning, A. Catalina Gebhardt, M. Alicia Irurzun, Wojciech Tylmann, Christoph Vogt, Claudia S. G. Gogorza   +6 more
wiley   +1 more source

Organic matter characteristics in black shales of the southwestern paleogene N'kapa formation, Douala Sub-basin Cameroon: Evidence from stable isotopes and rock-eval pyrolysis

Evolving Earth
Shallow marine black shales from outcrops, river channels, drilled and dug wells in Dibombari-Kompina-Mian (Stage-1) and Pendanboko (Stage-2) of the Paleogene N'kapa Formation in Douala Sub-basin were studied.
Ngong Roger Ngia, Elie Fosso Menkem, Alexandrine N'nanga, Christopher Fuanya, Median Yongye   +4 more
doaj   +1 more source

(Ultra)high‐Pressure Metamorphism in Sedimentary Versus Basaltic Rocks: Insights From a Variscan Mélange in the South Carpathians

Journal of Metamorphic Geology, EarlyView.
ABSTRACT Reconstructing the pressure–temperature–time (P–T–t) evolution of (ultra)high‐pressure rocks is essential for constraining subduction and collisional dynamics. Subduction zones are often investigated using basic eclogites, whereas nonbasic high‐pressure rocks remain comparatively understudied, potentially hindering a comprehensive ...
Otavio S. G. Silva, Bruno V. Ribeiro, Gavril Săbău, Fabricio Caxito, Paulo A. de Paiva‐Silva, Pierre Lanari, George Luvizotto, Mahyra Tedeschi   +7 more
wiley   +1 more source

Origin and Enrichment of Vanadium in the Lower Cambrian Black Shales, South China. [PDF]

ACS Omega, 2021
Wu T, Yang R, Gao L, Li J, Gao J.
europepmc   +1 more source

Widespread complex enameloid microstructure in teeth and rostral denticles of Cretaceous sclerorhynchoid skates (Rajiformes: †Sclerorhynchoidei)

Journal of Anatomy, EarlyView.
This article demonstrates that the teeth and rostral denticles of an extinct clade of sawfish‐like skates display an extremely derived enameloid microstructure, similar to what is known among sharks. The presence of tooth‐like enameloid microstructure in dermal denticles opens new perspectives about the origins and development of chondrichthyan ...
Endy Chateauneuf‐Gautier, Guillaume Guinot   +1 more
wiley   +1 more source

From Siliciclastics to Carbonates and Black shales: Deciphering Sedimentary Continuity and Discontinuity in the Devonian Landscapes of the Volga-Ural Petroleum Province

Georesursy
Analyses of the three predominant types of sedimentation – siliciclastic, carbonate and black shale – revealed their discontinuity/continuity across various facies environments within the Middle and Late Devonian of the central part of the Volga-Urals ...
V. V. Silantiev, D. N. Miftakhutdinova, N. G. Nurgalieva   +2 more
doaj   +1 more source