Results 51 to 60 of about 729 (236)

Petrogenesis of Huichizi granite and hosted amphibolite lens: implications for early Paleozoic evolution of the North Qinling orogenic belt

Frontiers in Earth Science
The genesis of Early Paleozoic granite and its relationship with multi-stage metamorphism in the North Qinling Tectonic Belt (NQTB) are heavily debated and limit our understanding on the evolution of the Qinling Orogenic Belt. In this paper, we conducted
Zhenhua Cui, Danling Chen, Yunfei Ren, Bowen Bai, Yuan Tang, Long Ma, Minglei Liu   +6 more
doaj   +1 more source

Confirmation of the impact origin of the Late Ordovician Tvären impact structure (southeast Sweden) and emplacement of impactites in a marine setting

Meteoritics &Planetary Science, EarlyView.
Abstract The Tvären structure in southeastern Sweden has been listed as a confirmed marine‐target impact structure for decades. However, to date, no measurements and/or indexed data of planar deformation features in quartz grains from the structure have been published or any other unequivocal evidence of impact.
Katarzyna J. Gajewska, Sanna Alwmark, Mikael Calner, Sylvain Richoz, Jens Ormö, Erik Sturkell, Carl Alwmark   +6 more
wiley   +1 more source

The effect of terrestrial weathering on the mineralogy and petrologic (sub)types of CM chondrites explored by kinetic modeling and laboratory experiments

Meteoritics &Planetary Science, EarlyView.
Abstract Terrestrial weathering alters the chemical and isotopic composition, and mineralogy, of meteorites; its effects on ordinary chondrites are well‐studied, but relatively little is known about the susceptibility of carbonaceous chondrites. We combined laboratory experiments, whereby Chwichiya 002 (C3‐ung find), Murchison (CM2 fall) and Kolang ...
Robin L. Haller, Martin R. Lee, Mark E. Hodson   +2 more
wiley   +1 more source

Petrogenesis of the paleoproterozoic ultramafites in Wuchuan area, Inner Mongolia: implications for tectonic evolution

Frontiers in Earth Science
IntroductionThe east-west trending Khondalite Belt, located on the northern margin of the North China Craton, is linked to the Paleoproterozoic Columbia supercontinent’s evolution.
Hao Hu, Dongyan Zhong, Zhiguang Zhou, Guosheng Wang, Shen Gao, Jianfeng Chen, Chenfei Feng   +6 more
doaj   +1 more source

Sedimentology of silica granules and haematite in the 3.47 Ga Antarctic Creek Member, Mount Ada Basalt, Western Australia

Sedimentology, EarlyView.
ABSTRACT The Paleoarchean Antarctic Creek Member of the Mount Ada Basalt, Eastern Pilbara Terrane, Western Australia, includes beds of jasper and white chert composed of sand‐sized silica granules that often contain or are mixed with silt‐sized particles of haematite.
Donald R. Lowe, Gary R. Byerly
wiley   +1 more source

Electron Microprobe Reintegration Method for Clinopyroxene Breakdown with Lamellae Exsolution

Yankuang ceshi
Pyroxene is an important rock-forming mineral in magmatic to metamorphic rocks, which often possesses certain breakdown texture with lamellae exsolution under temperature and pressure changes.
Xiaoli LI, Lifei ZHANG
doaj   +1 more source

Volcanostratigraphic Sequences of Kebo-Butak Formation at Bayat Geological Field Complex, Central Java Province and Yogyakarta Special Province, Indonesia

Indonesian Journal on Geoscience, 2016
DOI:10.17014/ijog.3.2.77-94Bayat Complex is usually used as a work field for students of geology and other geosciences. The study area is located in the southern part of the Bayat Complex.
Sri Mulyaningsih
doaj   +1 more source

Linking Stress Drop and Slip Heterogeneity to Assess Source Rupture Directivity for Earthquakes in Central Italy

Terra Nova, EarlyView.
ABSTRACT In this study, we examine the relationship between Brune stress drop and fault slip where the stress drop is estimated using the Empirical Green's Function (EGF) method and slip distribution is derived from seismic and geodetic data inversion.
Calderoni Giovanna, Antonella Cirella, Aybige Akinci   +2 more
wiley   +1 more source

Mineral chemistry of garnet in pegmatite and metamorphic rocks in the Hamedan area

Journal of Economic Geology, 2015
Introduction The area of this study is located near Hamadan within the Sanandaj - Sirjan tectonic zone. In the Hamadan area, consisting mainly of Mesozoic plutonic and metamorphic rocks, aplites and pegmatites locally contain garnets.(Baharifar et
Ahmad Ahmadi Khalaji, Zahra Tahmasbi
doaj  

Petrography and mineral chemistry of metamorphosed mantle peridotites of Nain Ophiolite (Central Iran)

Journal of Economic Geology, 2017
Introduction Study of the petrology of the ophiolites as the relics of ancient oceanic lithosphere, is a powerful tool to reconstruct Earth’s history. Mantle peridotites have mostly undergone alteration and serpentinization to some extent.
Nargess Shirdashtzadeh, Ghodrat Torabi, Ramin Samadi   +2 more
doaj   +1 more source