开鲁盆地陆东凹陷九佛堂组--沙海组地震相研究

摘要

Ludong Depression is the peripheral exploratory area of Liaohe Oilfield Company. Based on the seismic reflection termination relationship and the regional geological background, the Jiufotang Formation and Shahai Formation in Ludong Depression can be divided into two seismic sequences, i.e., the Jiufotang sequence and shahai sequence. According to the internal reflection texture and external geometric configuration and in combination with the parameters of amplitude and continuity, six seismic facies are identified in the target sequences of the study area, including parallel sheet, sub-parallel sheet, wedge shaped, foreset, unorganized and lenticular seismic facies. And their characteristics are described in detail. These seismic facies show variations in horizontal distribution and are successive and evolutionary vertically. Seismic facies are correlated to sedimentary facies through a comprehensive interpretation. The seismic-sedimentary facies model of each sequence is established according to the lacustrine sedimentary theory. The results show that the sedimentary facies of fan delta, nearshore submarine fan, turbidite fan and lake was developed in the target sequences.%开鲁盆地陆东凹陷是辽河油田的外围探区，依据地震反射终止关系，结合区域地质背景，将陆东凹陷下白垩统的九佛堂组-沙海组划分成2个地震层序，即九佛堂层序和沙海层序。利用地震反射内部结构和外部几何形态，结合地震反射同相轴的振幅和连续性等参数，在九佛堂层序和沙海层序内识别出平行席状、亚平行席状、楔状、前积、杂乱、透镜状共6种地震相，并对其特征进行了描述。各种地震相平面分布具有差异性、纵向上具有继承性和演化性。经过综合解释，建立地震相与单井沉积相之间的响应关系，把地震相转化为沉积相。以湖泊沉积理论为指导，建立目的层各层序地震相-沉积相模式，结果表明，目的层主要发育扇三角洲、近岸水下扇、浊积扇以及湖泊等沉积相。