东海陆架盆地西湖凹陷花港组原型盆地性质厘定
Prototype Basin Chracterization of Huagang Formation of Xihu Depression, East China Sea Shelf Basin

西湖凹陷是东海陆架盆地最主要的含油气构造单元，渐新世花港组是西湖凹陷重要的油气勘探目的层系，然而对于花港组沉积时期原型盆地的性质却一直存在争议且缺乏有说服力的证据.以最新的区域二维地震资料解释为基础，通过对关键不整合界面特征、盆地充填几何形态、盆地边界改造特征等方面的系统分析，提出西湖凹陷花港组原型盆地为一大型挤压挠曲坳陷型盆地，花港组底界面T30为盆地挤压背景下广泛发育的一个区域隆升侵蚀型不整合界面，是花港组原型盆地的成盆界面.花港组顶界面T20主要是受钓鱼岛隆褶带隆升活动控制的局部隆升侵蚀型不整合面，是花港组原型盆地的改造界面.在上述认识的基础上，进一步建立了花港组原型盆地的形成演化模式.
Xihu depression is the most important petroliferous structural units, and the Huagang Formation is the major target stratum for petroleum exploration in the East China Sea shelf basin. However, the prototype basin type of Huagang period is still controversial and lack of persuasive evidences up till now. According to the 2D seismic data interpretation, the system analysis of key surfaces features, basin infilling geometry, basin transforming and erosion, it is proposed that the Huagang prototype basin is a largescale compressional depression. The T30 seismic reflector, which acts as the initial surface of Huagang prototype basin, represents a regional uplift erosion unconformity under compressional background. The T20 seismic reflector, which acts as the transforming surface of Huagang prototype basin, mainly stands for a regional uplift-erosion unconformity controlled by the uplifting activities of Diaoyu Dao folded-uplift belt. Further, the formation and evolutionary model of Huagang prototype basin is established