Results 51 to 60 of about 1,440 (281)

Decoding Metamorphic Nanodiamonds Formation Through Their Internal Structures

Journal of Metamorphic Geology, EarlyView.
ABSTRACT Metamorphic diamonds offer insights into Earth's evolution, modulating the global carbon cycle through subduction into the mantle and exhumation. However, the formation and internal structure of minute diamonds remain poorly understood. Here, we study the internal structures of diamond‐bearing inclusions from the Eastern Alps using state‐of ...
Tim Sotelšek, Marian Janák, Sašo Šturm, Sorour Semsari Parapari, Nik Gračanin, Kristian Radan, Mehmet Ali Gülgün, Stanislava Milovská, Mirijam Vrabec   +8 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

Vertical profiling of shock attenuation at the Rochechouart impact structure, France

Meteoritics &Planetary Science, EarlyView.
Abstract Rochechouart, south‐west France, is a complex impact structure. Here, we present the first report of shock barometry of quartz from what are likely parautochthonous basement units at depth, based on samples from the 2017 C.I.R.I.R drilling campaign. The crystallographic orientations of 725 sets of PDFs in 512 quartz grains in samples from four
P. Struzynska, S. Alwmark, C. Alwmark, M. H. Poelchau, P. Lambert   +4 more
wiley   +1 more source

Metamorphic Inheritance, Lower‐Crustal Earthquakes, and Continental Rifting

Geochemistry, Geophysics, Geosystems
The Malawi Rift is localized within Precambrian amphibolite‐granulite facies metamorphic belts, bounded by up to 150 km long border faults, and generates earthquakes throughout ∼40 km thick crust.
Å. Fagereng, J. F. A. Diener, C. J. Tulley, B. Manda   +3 more
doaj   +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

The effect of early diagenetic processes on the quantification of fossil micrometeorite abundance and flux in the geological record

Meteoritics &Planetary Science, EarlyView.
Abstract Fossil micrometeorites (MMs) recovered from lithified sedimentary rocks, particularly iron‐rich (I‐type) cosmic spherules (CSs) provide valuable insights into past dust‐forming events. Their abundances, when combined with estimates of local sedimentation rates can be used to reconstruct the flux of extraterrestrial dust.
Isabelle S. Mattia, Matthew J. Genge, Martin D. Suttle   +2 more
wiley   +1 more source

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

Exploring the Gravimetric and Geochronological Links in Ancient Terranes of the São Francisco Craton and Borborema Province, NE‐Brazil

Terra Nova, EarlyView.
ABSTRACT Deep crustal fragments and structural lineaments identified through satellite gravity data provide evidence for the extension of the reworked ancient basement of the Central African Block into the northern São Francisco Craton and southern Borborema Province.
Douglas Teixeira Martins, Wagner da Silva Amaral, Felipe Holanda dos Santos, Evilarde Uchôa Filho   +3 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