The Distribution of Detrital Zircon U-Pb Ages and Its Significance to Precambrian Basement in Tarim Basin
塔里木盆地碎屑锆石年龄分布对前寒武纪基底的指示

In order to get the information concerning the relationship between the Tarim Precambrian basement and the supercontinent, the authors analyzed the U-Pb isotopic ages of zircons from 11 clastic rocks in different areas of Tarim Basin in situ by means of LA-ICP-MS. The results show that there existed Early Paleoproterozoic provenance in northern Tarim and Middle Mesoproterozoic provenance in southern Tarim. An analysis of detrital zircon ages and data of surrounding orogenic belts indicates that a uniform Tarim basement did not exist in Paleo-proterozoic and Mesoproterozoic, during which the North and South Tarim continents had different evolution events. The North Tarim continent probably had the same tectonic event as the breakup of Columbia superconti-nent. The collision between North and South Tarim continents took place in Early Neoproterozoic, resulting in the formation of a uniform Tarim basement. All of the clastic rocks have Nanhuan ages, which indicates that there was a large scale breakup of the Tarim continent in Nanhuan period. The thermo-tectonic event in Nanhuan period provided widespread provenance of the cap rocks. The Tarim continent might have had the same tectono-thermal events as the breakup of the Rodinia supercontinent. These results have yielded new intraplate evidence for con-straining the relation between the Tarim plate and the supercontinent.