摘要
应用地震资料解释数据,通过层拉平技术、古地层厚度计算可以实现古构造恢复和构造演化的精细研究。该技术是在研究地层及地震波组反射特征基础上,通过对多口探井制作合成记录,从而准确标定出主要目的层的反射波组,再利用地震剖面层拉平技术研究不同层的构造剖面演化,利用目的层底、顶的三维地震解释数据恢复关键沉积构造期的古构造形态并进行立体显示,在平面上精细刻画出关键构造期的构造变化特征。利用该技术恢复的鄂尔多斯盆地镇泾地区的古构造特征合理解释了该区现今的油气分布规律。侏罗系沉积前,该区已经发育多个鼻状隆起,且其后的沉积地层具有一定的继承性。上三叠统延长组烃源岩在经历了中侏罗世晚期的热事件后进入生烃门限,并开始排烃,于早白垩世中晚期达到生油高峰时,油气有利聚集区已经形成,主力烃源岩在生烃增压作用下产生的石油就近运移进入延长组长81、长9段等油层组河道砂岩,形成自生自储自盖型油藏。对该区油气分布规律的认识,为下一步的有利圈闭优选提供了技术支撑。
Paleo-structures can be resumed and the fine studies of tectonic evolution can be achieved using bedding flattening technique and paleo-stratigraphic thickness calculation based on the interpretation of seismic data.The synthetic records of stratigraphic and seismic refection characteristics of multiple wells were made so as to accurately calibrate the reflection wave group of the main target layer.The tectonic profiles of different layers were studied using bedding flattening technique.The three-dimensional seismic interpretation data of the bottom and top of the target layer was used to restore the paleo-structural morphology of the key sedimentary period,and to perform a three-dimensional display.In this way,the characteristics of structural changes in the key sedimentary period were finely depicted on the plane.The paleo-structural characteristics of the Zhenjing area in the Ordos Basin recovered by this technique reasonably explain the present law of oil and gas distribution.Before the deposition of the Jurassic,several nose-like uplifts had developed in this area,and the subsequent stratigraphic deposits have a certain degree of inheritance.The source rocks of the Upper Triassic Yanchang Formation entered the hydrocarbon generation threshold after experiencing thermal events during the late Middle Jurassic and began to expel hydrocarbons.Oil generation peak occurred in the middle and late periods of the Early Cretaceous,and some favorable hydrocarbon accumulation areas were formed.The oil produced by the main source rocks under the pressurization of hydrocarbon generation migrated into the channel sandstones of the Chang 81 and Chang 9 oil groups nearby,forming self-generating,self-storing and self-capped oil reservoirs.The understanding of the oil and gas distribution law in this area provides a technical support for the further optimization of favorable traps.
作者
荆克尧
陈霞
金晓辉
JING Keyao;CHEN Xia;JIN Xiaohui(SINOPEC Petroleum Exploration&Production Research Institute,Beijing 100083,China)
出处
《石油实验地质》
CAS
CSCD
北大核心
2021年第2期354-359,共6页
Petroleum Geology & Experiment
基金
中国石化科技部项目(P18055-2)
中国石化油田事业部项目(G5800-19-ZS-YTB001)联合资助。
关键词
三维地震资料
层拉平技术
古构造恢复
鄂尔多斯盆地
3D seismic data
bedding flattening technique
paleo-structure restoration
Ordos Basin
