Characteristics of the Geotectonics in South China and Their Constraints on Primary Diamond

Abstract

The Asian continent is one of the best places in the world to study continental dynamics. In this region the tectonic framework of the South China plate is related to the activity of the Pacific plate and Indian plate since the Mesozoic. In the South China plate, as the ophiolitic mélange of the middle Proterozoic in the Shaoxing‐Yingtan‐Tengxian‐Beihai faulted zone was confirmed to be a subducting ocean, the evolution of the Yangtze block and Cathaysian block, which are located on both sides of the fault zone, becomes clearer and clearer. A primary diamond deposit, which was first found by Bao Chaomin and his colleagues in Longyou County of Zhejiang Province in 1998, originated from kimberlitoid pipes. The pipes are located in the Cretaceous basin beside this deep fault and the diamond‐bearing pipe was formed deep within a favourable geological structure. Diamond there occurs as octahedral crystals without visual impurities. There are more than 100 similar pipes in the area, which have been poorly studied so far, so this area should have great prospects for diamond exploration.

Active Motion of Tectonic Blocks in East Asia: Evidence from GPS Measurement

“…The tectonics of East Asia is characterized by the subduction of the Pacific plate and the Philippine plate, and the eastward expulsion caused by the collision of India with Eurasia (Kogan et al, 2000;Kato et al, 1998;Tang and Bao, 2000) and has a peculiar feature. The inter-plate deformation and interaction between the blocks are very complicated.…”