Variscan Transform Zone in the Junggar Region
【摘要】:正 Transform faults or transforms have been discovered more than 30 years ago (Wilson,1965). Nevertheless, the descriptions of paleoanalogs of these important plate-tectonic structuresare still lasking in the geological literature. There are only two papers argumenting the existenceof an ancient oceanic transform conjugated with the oceanic ridge fragment that occur in the westNewfoundland ophiolites obducted during the Takonian epoch (Casey, 1985; Elthon, 1986).However, these papers are based on geochemical and petrostructural dare and touch upon thedeep-seated transform zone manifestations. Due to scarcity of geological evidence, thesynsedimentary transform structures are not discussed there. This paper is the first attempt to castsome light upon the structurai and evolutional peculiarities of paleotransform zone in the “are-transform-are” system forming the oceanic plate edge. The zone was detached by space and time-analysis of different complexes among Variscan structures of Junggar region which was untilrecentiy one of the least studied areas of the Central Asian mobile fold belt. The Junggar regionproved to be the key region for understanding geodynamics and tectonic evolution of the high-angle junction zones, widespread in the Asian Paleozoids, whose origin is the point of numerouscontroversies.