The distribution of time and space of Chinese ophiolites, and their tectonic settings.
中国蛇绿岩的分布、时代及其形成环境

Ophiolites are widely distributed in China, particularly in the western, southwestern and northern parts of the country, and rarely in the middle and south parts. The ophiolites fall into four principal age groups: PrQterozoic, early Paleozoic, late Paleozoic and Mesozoic-Cenozoic. The Proterozic ophiolites occur sporadically in China. The Phanerozoic ophiolites in China are grouped into five series, namely the Paleo-Asian Ocean series, the Qinling-Qilian-Kunlun Ocean series, the Paleo-Tethyan series, Neo-Tethyan series and the Circum-Pacific ophiolites. The Paleo-Asian Ocean ophiolites crop abundantly out in the northern part of China north of Tarim and the North China Block. The Qinling-Qilian-Kunlun Ocean lies among Tarim, the North China and Yangtze blocks. The Paleo- and Neo-Tethyan oceans are confined to the southwest China, and the Circum-Pacific series include the NE China and Taiwan ophiolites. Chinese ophiolites are geochemically complex and two or more lava types commonly occur within a given ophiolite sequence. Most ophiolites in the Palaeo-Asian, Neo-Tethyan and Circum-Pacific belts contain IAT and/or boninite indicating a suprasubduction zone origin. MORB lava in these bodies may have been originated in back-arc basins or may represent relict fragments of normal ocean lithosphere. Paleo-Tethyan ophiolites have mostly MORB lavas and lack typical suprasubduction zone components (such as IAT and boninite). Thus, they probably formed in intracontinental ocean basins.