【作者】 王升兰；

【导师】 姜在兴；

【作者基本信息】 中国地质大学（北京） ， 矿产普查与勘探， 2008， 硕士

【摘要】 以高分辨率层序地层学、沉积学、测井地质学、构造地质学等理论为基础,综合岩心、测井、录井、分析测试等多种资料,对博兴洼陷沙四上亚段滩砂和坝砂的成因、类型、沉积特征以及控制因素进行了综合的研究,取得了以下成果和认识:(1)根据博兴洼陷碎屑岩滩坝的岩性特征,将其分为砂质滩坝和砾质滩坝。(2)砂质滩坝沉积特征:坝砂单砂层较厚,层理类型以平行层理、浪成沙纹层理及波状层理为主;生物碎片发育,反应其较强水动力沉积条件;生物潜穴多为垂直型和倾斜型。滩砂单砂层较薄,泥岩夹层发育,层理类型以冲洗交错层理、波状层理、透镜状层理为主;碳屑较发育;潜穴以倾斜型、水平型为主。(3)砂质滩坝电性特征:自然电位、伽马及电阻率等测井曲线上,坝砂多对应宽幅正向指形或齿化的漏斗形;滩砂多对应异常幅度较高的“尖刀状”指形密集组合。成像测井上,由于坝砂体具有单砂层厚、泥岩夹层薄的特征,表现为亮色条带中夹有暗色条带;滩砂体单砂层较薄,成像测井图上表现为暗亮相间条带夹于滨浅湖暗色泥岩之中。(4)砾质滩坝特征:博兴洼陷砾质滩坝紧邻鲁西隆起发育,其砾石具有磨圆度高、倾角小的特点,测井曲线多为齿化的箱形及齿化漏斗形,大盐湖砾质滩坝发育明显的低角度层理。(5)滩坝砂体控制因素:古地貌、古水动力条件、古物源条件及基准面的变化是滩坝砂体发育的四个主要控制因素。(6)博兴洼陷低位体系域滩坝较为发育,是以下因素综合作用的结果:①古地貌条件:洼陷内发育一金家-樊家鼻状构造带,为滩坝砂岩的沉积提供了有利的地形条件;②水动力条件:低位体系域为湖盆断陷的初期,洼陷整体处于水体浅、水动力强的背景之下;③物源条件:低位体系域时期南部鲁西隆起为滩坝砂岩的形成提供了足够的物源;④基准面:低位体系域时期基准面相对稳定,有利于滩坝砂体的发育;⑤保存条件:博兴洼陷沙四上亚段后期基准面快速上升,已形成的滩坝砂体不易被破坏。更多还原

【Abstract】 Based on the research about the core data, the log data, the well log information, the analytical data, the testing data and so on, this paper studies the genesis, the types, the controlling factors and the sedimentatary features of beach and bar in the Sha4 upper Member in Boxing sag, according to the theory of high resolution sequence stratigraphy, sedimentology, well log geology, tectonic geology and so on. The main achievements are as follows:(1) According to the features of the clastic beach-bars in Boxing sag, they can be divided into sandy beach-bar and pebbly beach-bar.(2) Sedimentary features of sandy beach and bar: A single sand layer of bar is relative thick and it is much thinner of beach. The main bedding types of bar are parallel bedding, wave bedding and wave-built cross bedding. There are a lot of fossil fragments, which prove that the hydrodynamic force is strong. Its burrows are main angled and vertical. The main bedding types of beach are swash bedding, wave bedding and linsen bedding. Its burrows are main angled and horizontal.(3) Well log features of sandy beach and bar: The shape of bar is wide forward dactylic or jagged hopper. And the beach is the association of the highly abnormal amplitude dactylitic curve. In FMI, the features of bar is that between the bright belts there are several thin dark belts and the features of beach is that the bright and dark belts are interbedded.(4) The features of pebbly beach-bar: The roundness of the gravels in beach-bar is good. Its well log shapes are mainly jagged hopper or jagged box.(5) The controlling factors: There are four important controlling factors of the development of beach and bar, which are the palaeogeomorphology, the sources, the palaeohydrodynamic condition and the change of the base level.(6) There are five main conditions that the beach and bar are more development in lowstand systems tract. They are: the Jinjia-Fanjia nosing structure, the enough sources supplied by LuXi uplift, the strong palaeohydrodynamic condition, the sustained base level and the good preservation condition.更多还原