Results 51 to 60 of about 12,911 (237)
Proterozoic basins of Canada: Early Proterozoic sequences in Labrador
, 1981 Early Proterozoic ( Aphebian) sedimentary and volcanic rocks in Labrador are described from two tectonic belts: the Churchill Province of western Labrador, and the Makkovik Subprovince of eastern Labrador. The Aphebian in the Churchill Province is represented mainly by the Labrador Trough ( Kaniapiskau Supergroup) but also in the Laporte Croup, Lake ...
R J Wardle, D G Bailey
openaire +1 more source
Revisiting the Hummeln structure, Sweden—A shallow marine Cambrian impact structure
Meteoritics &Planetary Science, EarlyView.Abstract Hummeln is a simple impact structure located in south‐eastern Sweden. It is approximately 1.2 km in diameter and almost completely covered by a lake. Here, we present the first detailed investigation of impactites and mapping of the 164.25 m deep drill core Hummeln‐1 with a focus on impact metamorphism and the impact process.
S. Alwmark +8 more
wiley +1 more source
Frontiers in Earth Science, 2020 Archean-Proterozoic boundary represents a significant transitional phase in the Earth's history. Bastar Craton is one of the major Archean cratons in the Indian subcontinent with voluminous granites, supracrustal rocks, and tectonic belts.
Ajay Dev Asokan +4 more
doaj +1 more source
Criteries and prospects of diamonds of the Vitebsk granulite massif
Журнал Белорусского государственного университета: География, геология, 2021 The article describes the history of studying the diamond content of tectonic structures of the territory of Belarus. Based on the results of magnetometric, mineralogical, tectonic studies carried out by industrial geologists and scientists over the past
Victor S. Konishchev +1 more
doaj +1 more source
A carbonate-banded iron formation transition in the Early Protorezoicum of South Africa [PDF]
, 1992 Seven new and two resurveyed stratigraphic sections through the important carbonate-BIF transition in Griqualand West are presented and compared with six published sections.
Lamprecht, W. +3 more
core +1 more source
Early Proterozoic Evolution of the Grenville Belt: Evidence from Neodymium Isotopic Mapping, North Bay Ontario [PDF]
, 1990 Detailed Nd isotopic mapping in the southwestern Grenville Province between North Bay, Ontario, and Temiscaming, Quebec has revealed the precise trend of the proposed Penokean-aged suture discovered during reconnaissance isotopic mapping by Dickin ...
Holmden, Christopher
core
The Precambrian marine carbonate isotope database: version 1.1.
, 2002 We present a compilation of strontium, carbon, and oxygen isotope compositions of roughly 10,000 marine carbonate rocks of Archean - Ordovician age (3800 Ma – 450 Ma).
Shields, GA +5 more
core +1 more source
The West Gondwana margin : Proterozoic to Mesozoic [PDF]
, 2008 The longevity and extent of the oceanic southern margin of Gondwana have made it the subject of intense study for more than 70 years. It was one of the cradles of terrane theory and remains a proving ground for theories of supercontinent amalgamation and
Casquet Martín, César +4 more
core +1 more source
The structure of the Western and Central parts of the Ukrainian schield. Controversial issues
Геофизический журнал, 2018 Some controversial issues of composing the Scheme of the fault megablock tectonics of the western half of the Ukrainian shield in connection with the decision of the Interdepartmental Tectonic Committee of Ukraine on drawing up the Tectonic map of the ...
О. B. Gintov +7 more
doaj +1 more source
Old subcontinental mantle zircon below Oahu
Communications Earth & Environment, 2021 Oceanic mantle-derived zircon grains recovered from pyroxenite xenoliths in Hawaii have 14-million-year-old rims, Cretaceous cores and Proterozoic lutetium-hafnium model-ages, according to mass spectrometry and electron microprobe analyses.
John D. Greenough +7 more
doaj +1 more source