科研之友
微信
新浪微博
Facebook
分享链接
摘要
The Tanshan complex pluton is located in the northern margin of Jiangnan transition belt, which is the large complex pluton in the district. In this study, the authors systematically investigate the geology, geochronology and geochemistry of Tanshan complex pluton. The geological characteristics show that Tanshan complex pluton intruded along the axis of Yangmeiqiao anticline, which can sub-divided into alkalifeldspar granite, syenogranite and monzogranite from lithologically. The LA-ICP-MS U-Pb dating results of the alkalifeldspar granite and syenogranite intrusions are 128.9±1.6 Ma~128.8±2.5 Ma and 129.8±2.6 Ma~ 129.2±1.8 Ma respectively. Combined with the published age of the monzogranite intrusion (128.5±1.7 Ma~126.7±1.7 Ma), the Tanshan complex pluton was intruded in between 128.9± 1.6 Ma~126.7±1.7 Ma, which was corresponding to the last-stage magmatism of the 3 stage Yanshannian granitoid activities (Early: 153~146 Ma, Middle: 143~136 Ma, and Late: 135~121 Ma) in South Anhui district (135~121 Ma). All the alkali feldspar granite, syenogranite and monzogranite samples from Tanshan complex pluton exhibit the similar geochemical characteristic with A-type granite, which including high Alkaline, Ga/Al enriched ratios, in Rb, Th, Nd, Ce, depleted in Ba, Sr, P and Ti, and distinctly negative Eu abnormality. The multistage magma formed the Tanshan complex pluton was consistently derived from the lower crust, in the intracontinental tension background.
- 单位
