Certain geotectonic formations occurring before the Devonian in southeastern China

Abstract

1) In southeastern China the Archean group has not been found up to the present time. Here, the oldest rocks known are the Panhsi Proterozoic group and its equivalents, the age of which at the present time is regarded as proved. They are represented by rocks of geosynclinal type and consist of phyllites, “schiefer” slates, siliceous slates, metamorphosed sandstones and volcanic rocks. 2) South of the Chia-nan axis (north part of Kwangsi Province, south and central part of Hunan province, etc.) and north of it (central part of Kweichow province, San-hsia region) the “Sinian system” can be correlated; it consists mainly of formations of platformal type. From this it follows that at least the northern part of the South China Caledonian geosyncline is not a continuation of the Proterozoic geosyncline, but a newly emplaced tectonic element. Whether the entire South China Caledonian geosyncline or a large part of it was formed on the base of a “Sinian platform” is one of the important unsolved problems in the g...