Results 111 to 120 of about 31,687 (305)

Geochemistry and Geochronology of Magmatic Rocks in Southwestern and Northeastern Cambodia: Implications for the Tectonic Evolution and Metallogenesis of the Loei Fold Belt

Geological Journal, EarlyView.
The composition of intrusive rocks suggests that the magma was likely generated in a subduction‐related setting. The arc crustal thickness in the Phnom Sro Ngam and Halo Prospects was probably < 40 km during emplacement. Zircon U–Pb age range indicates a correlation with Loei Fold Belt magmatic activity.
Sirisokha Seang, Khin Zaw, Kakda Kret, Ivan Belousov, Kotaro Yonezu, Koichiro Watanabe, Charles Makoundi   +6 more
wiley   +1 more source

Mesozoic anomalies in the Bay of Bengal [PDF]

, 1994
The analysis of 8200 line km of total magnetic intensity data in the Bay of Bengal, northeastern Indian Ocean, revealed the presence of approximately N30°E-trending seafloor spreading type magnetic anomalies. These anomalies resemble the Mesozoic anomaly
Nair, R. R., Sarma, K. V. L. N. S., Paul, John, Krishna, K. S., D'Cruza, Maria, Ramana, M. V., Subrahmanyam, C., Subrahmanyam, A. S., Subrahmanyam, V., Ramprasad, T., Chandra Sekhar, D. V.   +10 more
core   +1 more source

Late Pleistocene Volcanic Rocks From Tengchong Volcanic Field at SE Tibetan Plateau: Constraints on Petrogenesis and Mantle and Crustal Processes

Geological Journal, EarlyView.
Early zircon saturation and crystallisation occur in mafic (52–54 wt.% SiO2) lavas at Tengchong volcanic field. These early formed zircons with high δ18O (6.6‰–7.9‰) indicates mantle enrichment by subducted supracrustal materials. ABSTRACT Late Pleistocene (< 0.2 Ma) mafic and evolved volcanic rocks occur in northern Tengchong Volcanic Field, SE ...
Lizhu Wang, Haibo Zou
wiley   +1 more source

Local Structures of Se and Br in Cretaceous–Paleogene Boundary Sediments and Concentration Effects of Ferrihydrite Originating From Impact Ejecta

Geological Journal, EarlyView.
Chemical states of Se and Br atoms in the KPg boundary sediments from Stevns Klint were studied using XAFS spectroscopy. The high concentrations of Se4+ could become an index of the degree to which the global environment was soiled with dust and ash derived from impact ejecta or volcanic eruptions.
Kei‐ichiro Murai, Akira Yoshiasa, Ginga Kitahara, Makoto Tokuda, Satoko Ishimaru, Toshihiro Moriga   +5 more
wiley   +1 more source

Review of the dental pattern in the squalomorph shark Protospinax annectans , and a description of two new Jurassic shark genera

Acta Palaeontologica Polonica
The extinct elasmobranch Protospinax is an intriguing shark known mostly from isolated teeth and rare complete skeletons. Most previous studies focused on differences in isolated teeth for taxonomic assignments, with little to no considerations of dental
Arnaud Begat, Eduardo Villalobos-Segura, Patrick L. Jambura, Manuel A. Staggl, Stefanie Klug, Jürgen Kriwet   +5 more
doaj   +1 more source

Apatite in Carbonatite Preserving Primary Magmatic, Post‐Magmatic Overgrowth, and Post India‐Asia Collision‐Related Hydrothermal Alteration: Evidenced From U–Pb Isotope and Trace Element Geochemistry

Geological Journal, EarlyView.
U–Pb isotope and trace element geochemistry of apatite from carbonatites of Peshawar Plain Alkaline Igneous Province, western Himalaya shows Permo‐Carboniferous magmatism, an additional magmatic pulse during Cretaceous, and post‐magmatic hydrothermal/metasomatism during Oligocene. ABSTRACT U–Pb isotope and trace element geochemistry of apatite combined
Mehboob ur Rashid, Hafiz U. Rehman, Hao‐Yang Lee, Sun‐Lin Chung, Kaushik Das, Kazumasa Aoki, Muhammad Jawad Zeb, Nasir Ahmad, Muhammad Hussain, Hiroshi Yamamoto   +9 more
wiley   +1 more source

Columnanidus calitzdorpensis ichnogen. ichnosp. nov: A new Middle Pleistocene subterranean termite trace fossil from South Africa

Journal of Quaternary Science, EarlyView.
ABSTRACT Termites are landscape geo‐engineers whose nesting activities substantially modify the physical and chemical properties of soils. Fossilised termite nests commonly constitute the only identifiable evidence of ancient termite activity and represent valuable trace fossil archives for reconstructing past environments.
Miengah Abrahams, Robert A. Muir, Jorge F. Genise, John E. Almond, Gcinamahlubi Hadebe, John C. Hellstrom, Rabia Jacobs, Chris Harris   +7 more
wiley   +1 more source

1. Palaeozoic and Mesozoic Foraminifera [PDF]

, 1931
Foraminifera are found in the Palaeozoic and Mesozoic deposits of the Netherlands East Indies. Palaeozoic forms have been described or recorded from Sumatra, Timor, Luang, and Letti, while Mesozoic ones are known not only from those islands, but also ...
Hanzawa, S., Yabe, H.
core  

Reciprocal relations shape cultural landscapes: Women's environmental stewardship in Ait Bouguemez (High Atlas, Morocco)

People and Nature, EarlyView.
Abstract Mountain social–ecological systems encompass steep ecological gradients and diverse cultural practices, yet the relative roles of these factors in shaping mountain landscapes remain underexplored. In particular, the knowledge and practices of women in coproducing biocultural landscapes are often invisible in the academic literature. In the Ait
Meryem Aakairi, Sara Elgadi, Hamza Zine, Christel Vidaller, Mohamed Cherkaoui, Emmanuel Corcket, Irene Teixidor‐Toneu   +6 more
wiley   +1 more source

Sedimentary provenance of the Hengyang and Mayang basins, SE China, and implications for the Mesozoic topographic change in South China Craton: Evidence from detrital zircon geochronology [PDF]

, 2011
Detrital zircon U-Pb data from sedimentary rocks in the Hengyang and Mayang basins, SE China reveal a change in basin provenance during or after Early Cretaceous. The results imply a provenance of the sediment from the North China Craton and Dabie Orogen
Yi Yan, Lung-Sang Chan, Chan, LS, Xiao-qiong Hu, Yan, Y, Hu, XQ, Lin, G, Ge Lin, Santosh, M, M. Santosh   +9 more
core   +1 more source