This work examines the global distribution of Archaean and modern igneous rock's compositions, without relying on preconceptions about the link between rock compositions and tectonic sites (in contrast with "geotectonic" diagrams). Rather, Archaean and modern geochemical patterns are interpreted and ...
Archaean 美[ɑrˈkiən] 英[ɑ:ˈki(:)ən] adj.【地质学;地理学】太古代的;太古代岩石的 n.【地质学;地理学】太古代;太古代岩石 网络太古宙;太古宇;前太古代 英汉 英英 网络释义 n. 1. 【地质学;地理学】太古代;太古代岩石 adj. ...
This foundational step in Earth’s evolution went at the expense of ancient proto-continental crust, which developed during the Hadean to Paleoarchaean and has since been largely removed from the rock record3. Although Archaean TTGs are central to crustal evolution and cratonisation, there is ...
Define archaean. archaean synonyms, archaean pronunciation, archaean translation, English dictionary definition of archaean. adj. Variant of Archean. American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton
The accretion of volatile-rich material from the outer Solar System represents a crucial prerequisite for Earth to develop oceans and become a habitable planet1–4. However, the timing of this accretion remains controversial5–8. It has been proposed tha
Formation history and protolith characteristics of granulite facies metamorphic rock in Central Cathaysia deduced from U-Pb and Lu-Hf isotopic studies of s... The petrochemical as well as zircon U-Pb and Lu-Hf isotopic studies of granulite facies metamorphic rock from the Taoxi Group in eastern...
2016). In the western part of northern Sweden, a final rock-forming phase is characterized by Ediacaran and Cambrian cover rocks, which during the Caledonian orogeny (0.5–0.4 Ga) were overthrust by nappes from the west. Fig. 1 Bedrock map of northern Norrbotten County modified from Bergman ...
In contrast, Grain 8 is very depleted in Th, with consistently low Th/U values around 0.01, more typical of high-grade metamorphic rocks11,12; we note that among the Archaean zircons, Grain 8 contains the youngest 207Pb/206Pb spot age (2,552±11 Ma, excluding analyses that partly ...
The Archaean bedrock of the Karelia and Belomorian Provinces is mostly composed of granitoids and volcanic rocks of greenstone belts whose ages vary from c. 3.50 to 2.66 Ga. Neoarchaean rocks are dominant, since Paleoarchaean and Mesoarchaean granitoids.
A high pressure basic granulite ultramafic rock belt, which is about 200km long and trends toward NE, occurs in the late Archaean orthogneiss in Laixi Laiy... Y Li - 《Scientia Geologica Sinica》 被引量: 48发表: 1997年 Effects of Reworking on High-Grade Gneiss Complexes early stages of...