楚雄盆地构造变动与后期改造综合研究

【作者】 房建军；

【导师】 刘池阳；

【作者基本信息】 西北大学 ， 岩石学、矿物学、矿床学， 2004， 硕士

【摘要】 楚雄盆地是我国南方具有良好石油地质条件的一个较大型中-新生代改造盆地。无论是从生产勘探开发还是科学研究的角度，都有必要对盆地中新生代的构造变动与后期改造进行综合研究。 本文主要在广泛查阅、学习和重新审视前人研究成果和第一手勘探资料的基础上，应用“整体，动态，综合”的盆地研究思路，对楚雄盆地中新生代的构造变动与后期改造进行研究。 楚雄盆地油气勘探和地质研究已有半个多世纪的历史，直到2000年该盆地才成功的钻探了两口区域深探井(乌龙1井和云参1井)，为揭示盆地腹部地质特征和油气赋存状况提供了难得的第一手资料和各种重要信息。本文从这两口探井所获得的实际资料入手，对有关地质构造和油气保存条件进行剖析。 通过对盆地乌龙1井热力改造的分析研究认为，乌龙口背斜属于热力构造，乌龙1井热力改造与区域性的高地温背景为其直接证据，其形成原因是构造变动作用下的岩浆-热液活动。明晰了构造变动的重要性，发现楚雄盆地的构造变动主要有岩浆、断裂和天然地震等活动形式。中新生代的岩浆主要分布在红河断裂带东侧，有火山岩和浅层侵入岩两种类型，其活动较复杂，具多期多阶段性。盆地内的断裂活动特征非常复杂，发育时期不同、规模大小不等、性质形态各异。盆地的现今天然地震活动强烈，主要分布在断裂带附近，盆地不同部位地震活动强度差异较大。 通过对盆地云参1井钻井液严重漏失的研究认为，云参1井钻井液漏失严重与在较广阔范围内发生非封闭性流体运动及交换直接有关，根本原因是构造变动作用下的断裂切割、差异隆升和强烈剥蚀导致的水动力改造。 在重点解剖乌龙1井热力改造和云参1井钻井液严重漏失和探讨其形成原因为基点，由点到面，继而对盆地及邻区中新生代岩浆活动进行研究，分析其对油气保存条件的影响。 构造变动(运动)为制约和影响各种改造作用的主导因素。本文以不整合面为主要研究对象，结合查阅、收集和整理其他相关研究成果和第一性资料，系统、全面地搜集整理了楚雄盆地及邻区的地层不整合剖面(点)154个，并结合构造、沉积和地球物理等相关资料，探讨盆地中新生代的构造变动，划分了楚雄盆地中新生代构造变动的期次和特征，确定不同期次不整合面的性质、展布范围、形成原因和基本特征；提出楚雄盆地在中新生代发育了9个不整合面，代表有9次较明显的构造变动。在中生代，盆地及邻区发生了5次较明显的构造变动，所表现的地层接触关系基本上都是平行不整合，构造变动表现为盆地整体的抬升和沉降，即在盆地发育阶段并无明显的构造变动。在新生代，盆地及邻区发生了4次较明显的构造变动，所表现的地层接触关系基本上都是角度不整合，构造变动表现为盆地强烈的构造变形和岩浆活动。 根据对构造变动期次和特征的研究，认为楚雄盆地是自晚三叠世开始形成演化、并经历了强烈构造变动的较大型中新生代改造型盆地，在中新生代经历了形成发育和后期改造两大构造演化阶段，盆地各演化阶段的性质和特征差异明显。更多还原

【Abstract】 Formed during Mesozoic-Cenozoic period, the larger reformed Chuxiong Basin in south of China has good petroleum geological condition. Whether in exploitation or in scientific study, it is necessary for us to study on tectonic evolvement and late reformation of the Basin in Mesozoic and Cenozoic period.On the basis of widely looking up, learning and rescanning preceding research and first-hand exploitation data, applying the thinking of "whole , dynamic and integration", this paper makes a study on the tectonic evolvement and late reformation of Chuxiong Basin in Mesozoic and Cenozoic period.It’s over half century in exploitation and geologic study, it was until 2000 that two deep test well were successfully drill in Chuxiong Basin (Wulong 1 and Yancan 1), which provide first-hand exploitation data and important information to show geologic character and oil-gas conservation in basin. The paper analyses geologic tectonic and condition of oil-gas conservation on the basis of data of the two well,.By the analysis of thermal reformation in Wulong 1, we think that anticline in Wulongkou belong to the thermal tectonic, the thermal reformation in Wulong 1 and the regional high thermal background are its immediate evidence. The action of magma and thermal liquids under tectonic change is its essential cause.By the analysis of the grievous loss of liquid in Yuncan 1, we think that it has immediate relation with the act and change of unclose liquid on the great scale because of fracture incision, different carina and strong erosion by tectonic change.After finding the cause of thermal reformation in Wulong 1 and the loss of well liquid in Yuncan 1 and on the basis of discussing their cause from point to surface, we discuss the effect on oil-gas preservation condition combining the study on magma act in Mesozoic and Cenozoic in basin and it’s around.Tectonic change (movement) is the main factor restricting and affecting each reformed action. In the paper, studying on unconformity surfaces, referring, collecting and cleaning up relative research and data, gathering 154 unconformity surfaces(points) by the numbers and combining with the data of tectonic, sediment and physical geography, we disscuse tectonic change in Mesozoic and Cenozoic, divide stage and character of tectonic and confirm property, distribution, formingcausing and basic character, then we find nine unconformity surfaces which show that there are nine obvious tectonic action in Mesozoic and Cenozoic in Chuxiong basin. The parallel unconformity surfaces by five obvious tectonic actions show the whole rise and sedimentation in basin. The four obvious angle unconformity surfaces in basin and it’s around tectonic action show the strong tectonic distortion and magma action.On the basis of the stage of tectonic change and character, we think Chuxiong Basin is a larger reformed basin formed from late Triassic and underwent strong tectonic change in Mesozoic and Cenozoic. Tectonic evolvement underwent two stages of basin growth and late-reformation, and the property and character of each stage are different.更多还原