东海盆地西湖凹陷花港组物源分析

Analysis on Provenance in Huagang Formation of Xihu Depression in the East China Sea Basin

通过锆石测年、重矿物ZTR指数、倾角测井等方法,对东海盆地西湖凹陷花港组(Eh)物源进行了系统分析。锆石测年表明,前寒武系物源来自于北部的虎皮礁隆起;中生界物源主要是来自西部的海礁隆起;古生界物源主要来自东部的钓鱼岛隆褶带。重矿物ZTR指数显示,西湖凹陷北部为主要物源区,但也存在东部点物源区和中部的多物源区。古水流数据显示,古水流方向呈北-南向。综合分析认为,Eh沉积时期受轴向主物源和侧向点物源共同影响,其中,以北部物源为主,东、西部点物源为辅。

Based on the systematic analysis of zircon age,heavy mineral ZTR index and dip angle logging,the provenance characteristics of Huagang Formation(Eh)in Xihu Depression of the East China Sea Basin were systematically studied.The analysis of zircon aging showed that the provenance of the Precambrian was mainly derived from northern Hupijiao Uplift,the provenance of the Mesozoic was mainly derived from the western Haijiao Uplift,while the provenance of Palaeozoic was mainly derived from eastern Diaoyu Islands Folded-Uplift Belt.The ZTR index of heavy mineral showed that the north Xihu Depression was the primary source area,but there was also east point-source and central multiple-source areas.The paleocurrent direction of Huagang Formation in Xihu Depression is mainly SN.Combined with the synthetic analysis,it is indicated that it is affected by the axial primary source area and lateral point-source,the provenance of Huagang Formation in the Xihu Depression is mainly derived from the northern primary source area and the western and eastern secondary point-source.