Results 171 to 180 of about 297,722 (205)

Chapter 8 Svecofennian supracrustal rocks

2005
Publisher Summary A substantial part of the Paleoproterozoic crust of southern and central Finland is characterized by 1.92 Ga turbiditic sedimentary and - 1.90-1.88 Ga arc-type volcanic rocks. Fluvial to shallow-water sedimentary rocks, felsic schists, sedimentary carbonates, black shales, and MORB- and WPL-like basalts are locally also common.
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The precambrian supracrustal rocks of Finland and their tectono-exogenic evolution

Precambrian Research, 1986
Abstract The Precambrian supracrustal rocks of Finland were produced during four main evolutionary stages: (1) late Archaean (Pre-Svecokarelidic) greenstone-schist evolution on an unknown basement; (2) at least four cycles of early Proterozoic (Karelian) continental-epi/pericontinental sedimentation and volcanism on or next to the cratonized late ...
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Chapter 7 Karelian supracrustal rocks

2005
Publisher Summary The most hampering thing is the lack of continuous vertical stratigraphic sections and the small size of the outcrops. The result is that unconformities and their correlative surfaces, which are essential in sequence stratigraphy, can be observed in a few places only.
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The metamorphism of the supracrustal rocks at Garpenberg, south central Sweden

Geologiska Föreningen i Stockholm Förhandlingar, 1984
Abstract The supracrustal sequence at Garpenberg, south central Sweden, consists mainly of felsic gneisses with subordinate intercalations of amphibolites and stratabound sulfide and iron deposits. During the Svecokarelian orogeny this sequence was isoclinally folded, metamorphosed and intruded by synorogenic granitoids.
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Possible link between the oldest supracrustal unit and the oldest rock unit of China

Precambrian Research, 2020
Abstract Caozhuang Group (or Caozhuang supracrustal sequence) in Eastern Hebei, North China Craton (NCC) may represent the oldest supracrustal unit of China. Abundant Eoarchean and Paleoarchean detrital zircons (up to 3.88 Ga) in paragneisses of Caozhuang Group provide valuable memories of the earliest crustal evolution of China.
Peng Liou, Xiahong Cui, Jinghui Guo, Mingguo Zhai   +3 more
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Correlation of the Precambrian Supracrustal Rocks of Coastal Labrador and South-western Greenland

Nature Physical Science, 1972
RECENT geological mapping and the compilation and publication of the first geological map of Labrador1 indicate that three broad groups of Precambrian supracrustal rocks, each separated in time by a principal orogenic cycle, can be recognized in coastal Labrador (Table 1).
J. S. SUTTON, B. E. MARTEN, A. M. S. CLARK, I. KNIGHT   +3 more
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Metamorphism of the supracrustal rocks in the Thompson Belt, Manitoba

1984
Regional deformation and amphibolite facies metamorphism affected supracrustal rocks of the Thompson Belt in north-central Manitoba. The metamorphic conditions of two metasedimentary rock sequences were studied and correlate with those observed by Peredery (1982).
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Geology, Age and Origin of Supracrustal Rocks at Akilia, West Greenland

American Journal of Science, 2006
New mapping, geochronology, and geochemistry of the supracrustal enclave and associated orthogneisses at Akilia, West Greenland, support a ≥3825 ± 6 Ma age for the sequence and a chemical sedimentary origin for the controversial Fe-rich quartz-pyroxene gneisses.
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Upper proterozoic supracrustal rocks of North America: A brief review

Precambrian Research, 1981
Abstract Well-preserved successions of supracrustal rocks of Upper Proterozoic age are present around the margins of North America but are rare in the continental interior. The thickest and most complete assemblage is present in the Cordilleran region, particularly in the central and northern parts.
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Homogenous deformation in precambrian supracrustal rocks of Kumlinge area, southwest Finland

Precambrian Research, 1976
Abstract Supracrustal rocks form a trough-like prolonged syncline surrounded by granitic rocks. They consist of quartz-feldspar schists (leptites) overlain by amphibolites. The stratigraphic succession in the syncline is as follows: undermost lie leptites followed by amphibolitic pillow lavas, which are gradually superseded by pillow breccias and ...
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