The development of the Mianyang-Changning intracratonic sag significantly influenced the Late Proterozoic
to Early Cambrian oil/gas occurrences in the Sichuan basin, that is, chiefly through its influence on the distribution of high-quality reservoirs in the Late Proterozoic
Dengying and Early Cambrian Longwangmiao formations and of source-rocks in the Niutitang Formation.
and Gostin, V.A., 1989, An exceptionally thick upper Proterozoic
(Sturtian) glacial succession in the Mount Painter area, South Australia: Geological Society of America, Bulletin, v.
Des Marais and his colleagues investigated the oxygen story by trying to estimate the global amount of organic carbon buried in seafloor sediments throughout the Proterozoic
. To do this, they compared data on the carbon isotopes within two types of rocks: shales, which record the isotopic value of carbon in organic matter, and carbonate rocks, which record the isotopic value of inorganic carbon in seawater.
These include a gold-bearing alluvial zone near Nkan 150 km east of Libreville, and gold mineralization in Ba-Au-Cu gossans and quartz-sulphide veins in Archaean greenstones and Lower Proterozoic
Hoffman, P.F., 1988, United plates of America, the birth of a craton: early Proterozoic
assembly and growth of Laurentia: Annual Review of Earth and Planetary Sciences, v.
During the early Proterozoic
eon, a series of orogenies and basin development affected the central part of West Africa with the formation of the now famous Birrimian volcano-sedimentary belts and the Tarkwaian molassic and conglomeratic deposition.
Then sometime during the late Proterozoic
era, about 580 million years ago, life got big.
Lode gold is emplaced into competent quartzites in Proterozoic
turbidites during |thin skin' tectonics in the external zone of the pre-Cambrian kibaran belt.
The mine is associated with the Lower Proterozoic
system of the Birimian comprising meta-volcanic and metasedimentary rocks.
- Regional exploration tenure over one of the most under-explored belts of Proterozoic
rocks in Australia.
These old age steps nearly always reach into the Mesozoic and sometimes into the Proterozoic
. The preservation of these pre-Cenozoic age steps requires that the Cenozoic maximum temperature did not exceed the closure temperature for diffusive Ar loss from muscovite.
and Phanerozoic mafic magmatic record is reviewed first since its links with LIPs are better defined (Table 1, Fig.
In 1992 the search for metals in the Archaean and reworked Archaean basement of West and Southwest Greenland continues as well as in the early Proterozoic
Karrat group in Northwest Greenland.
These deposits, which are of Late Proterozoic
age, contain 5 Mt with up to 25% [P.sub.2][O.sub.5] and represent a continuation of more extensive beds discovered previously in the neighbouring parts of Burkina Faso and Niger.
Now, a project in the Bay of Bothnia -- between Finland and Sweden -- has provided some of the clearest information yet about an ancient crash relatively early in the Proterozoic
era, which lasted from 2.5 billion to 570 million years ago.