Results 71 to 80 of about 1,440 (281)

Progress in the Application of Oxygen Isotopes in the Study of Petrogenesis

Yankuang ceshi, 2013
Since different types of rocks on the earth have different oxygen isotope compositions, they can be used to discuss the origins of various rocks and it has become a powerful tool for studying petrology.
LI Tie-jun
doaj  

Subcritical Cracking Associated With Subgrain Rotation Recrystallisation in Quartz Inferred From Cathodoluminescence Study

Terra Nova, EarlyView.
ABSTRACT We employed cathodoluminescence (CL) to study deformed quartz phenocrysts from the Cretaceous granite porphyry in SW Japan and observed fracture‐like planar structures appearing as CL‐dark bands. These CL‐dark bands were aligned with low‐angle grain boundaries formed by subgrain rotation recrystallisation.
Takuro Yoshioka, Takamoto Okudaira, Hideo Takagi   +2 more
wiley   +1 more source

Comparison of geochemistry and porphyry copper mineralization efficiency in granitoids of the Sanandaj-Sirjan and Urumieh-Dokhtar zones; using rare earth elements geochemistry

Journal of Economic Geology, 2019
Introduction The formation of the Zagros orogenic belt is attributed to northeastward oblique subduction of the Neotethys beneath the western border of central Iran.
Alireza Zarasvandi, Mohsen Rezaei, Majid Tashi, Zahra Fereydouni, Madineh Saed   +4 more
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

Geochemical and Isotopic Characteristics of the Protolith of Eclogites from the North Shahrekord Metamorphic Complex: Evidence of Late Neoproterozoic Back-arc Basin development in Sanandaj-Sirjan Zone

Journal of Economic Geology, 2019
Introduction All of the major tectonic zones of Iran, except for the Kopet-Dagh, contain Pan-African crystalline basement. Subduction of the Proto-Tethys at about 630 Ma caused Cadomian arc– and backarc magmatism in the northern margin of Gondwana ...
Forough Malek Mahmoudi, Ali Reza Davoudian Dehkordy, Nahid Shabanian Boroujeni, Hossein Azizi   +3 more
doaj   +1 more source

Mineral chemistry and geothemobarometry of mantle harzburgites in the Eastern Metamorphic Complex of Khoy ophiolite -NW Iran

Journal of Economic Geology, 2017
Introduction Khoy ophiolite at the global scale is in the middle part of the Alp-Himalaya orogenic belt and it is extended over 3900 Km2 which indicates remnant Neotethys oceanic lithosphere in the Mesozoic era (Kananian et al., 2010). In this paper, in
Morovvat Faridazad
doaj   +1 more source

Genesis and petrology of Late Neoproterozoic pegmatites and aplites associated with the Taba metamorphic complex in southern Sinai, Egypt

Geologica Acta, 2016
We present new field, petrographical, mineralogical and geochemical data from late Neoproterozoic pegmatites and aplites in southern Sinai, Egypt, at the northernmost limit of the Arabian-Nubian Shield.
K.M. ABDELFADIL, P.D. ASIMOW, M.K. AZER, H.A. GAHLAN   +3 more
doaj  

Post-Hercynian ultrahigh-temperature tectono-metamorphic evolution of the Middle Atlas lower crust (central Morocco) revealed by metapelitic granulite xenoliths [PDF]

Solid Earth
The study of metapelitic sillimanite- and garnet-bearing granulite xenoliths brought to the surface by the basanite of the 650 ka Tafraoute maar shed new light on the lower crust of the Tabular Middle Atlas (Morocco).
A. El Maz, A. Vauchez, J.-M. Dautria
doaj   +1 more source

Petrography and mineral chemistry of wehrlites in contact zone of gabbro intrusions and mantle peridotites of the Naein ophiolite

Journal of Economic Geology, 2014
Introduction Geological background Ophiolites have played a major role in our understanding of Earth’s processes ranging from seafloor spreading, melt evolution and magma transport in oceanic spreading centers, and hydrothermal alteration and ...
Farhad Ghaseminejad, Ghodrat Torabi
doaj  

Petrology and Metamorphic P-T Paths of Metamorphic Zones in the Huangyuan Group, Central Qilian Block, NW China [PDF]

, 2018
Zhuoyang Li, Yilong Li, Limin Zhao, Jianping Zheng, Fraukje M. Brouwer   +4 more
openalex   +1 more source