【作者】 陈明；

【导师】 陈洪德； 王剑；

【作者基本信息】 成都理工大学 ， 古生物学与地层学， 2004， 博士

【摘要】 本文以野外实地调研为基础,从沉积充填特征入手,运用多学科方法,分析了盆地的区域构造背景、基本格架、基底概况和盆内火成岩特征;详细研究了盆地各期地层发育特征和纵横向变化、沉积体系与沉积相、沉积相序和沉积体系时空配置、层序界面特征和准层序叠置序列、古地理演化:探讨了盆地的结构、性质及形成演化过程;简要论述了盆地的油气资源远景。通过研究,取得了以下成果和认识。 1、通过盆地的构造特征、火成岩特征、深部地震结构特征,再结合印度板块北缘岗巴-定日盆地的沉积特征等分析,对班公湖-怒江缝合带的俯冲方向和雅鲁藏布江缝合带的俯冲时限等争议较大的问题表明了自己的观点,研究认为,班公湖-怒江洋应向南俯冲,雅鲁藏布江洋应在早白垩世初开始向北俯冲。 2、依据地层发育特征、沉积建造、岩浆活动等因素,重新厘定了盆地地层分区,把原划归为木嘎岗日分区的日松-甲岗一带地层现划归为日松-革吉-它日错分区。 3、在岩石地层、生物地层研究基础上,提出了对班公湖-怒江缝合带内、且坎-古昌-阿索构造带内和两带之间的上侏罗统沙木罗组地层应赋予不同地层名称加以区分的建议。 4、根据盆地下白垩统郎山组生物礁的平面分布特征及与裂谷带的空间配置关系,提出了郎山组生物礁主要沿且坎-古昌-啊索裂谷带两侧分布。 5、通过沉积体系与沉积相、沉积相序与沉积体系时空分布、古地理展布研究,提出了中生代措勤盆地具有以且坎-古昌-阿索裂谷带为沉积沉降中心向南北两侧展开的沉积格局,该裂谷带是盆地的控相构造,它控制着盆地的沉积充填特征、古地理格局、生物礁分布及生储盖层的分布。并重新编制了盆地海相沉积期的岩相古地理图。 6、在对盆地海相沉积体的沉积旋回、层序界面特征、准层序叠置序列和体系域构成研究基础上,把盆地中晚侏罗世到早白垩世的沉积体划分了2个二级层序、13个三级层序,其中第一个二级层序为中晚侏罗世沉积,内部可划分为6个三级层序;第二个三级层序为早白垩世沉积,内部可划分为7个三级层序。 7、通过盆地的区域构造背景、沉积充填特征、物源的构造背景、火成岩特征等综合分析,认为中生代措勤盆地由中晚侏罗世裂陷型盆地和早白垩世双弧后裂陷盆地叠置而成的叠合型盆地。 8、根据盆地生储盖分布特征及成藏条件分析,提出了裂谷带两侧附近地区是盆地油气资源远景区,且革吉-仓木错、它日错-阿苏凹陷是盆地最有利的远景区块。更多还原

【Abstract】 Based on the field study, by combining sedimentary basin analysis with methods of the other subjects, the regional tectonic background and basic framework and basement structure and igneous rock character in the Coqen basin are analyzed. The Stratigraphic character, depositional system and facies, facies sequences and temporal and spatial distribution of depositional system, the sequence boundary signatures and parasequencs stacking pattern, palaeogeographic evolution are fully studied; The basin framework and character and forming processes are discussed; the resource potentialities of oil and gas in this basin are generally discussed. The advancements are as follow:1. Through the analyses of the tectonic and igneous rock and seismic reflection structure in Coqen basin, combing with sedimentary characteristics of the Ganba-Tingri basin in the north Indian plate, Author demonstrated oneself viewpoints about the difference of the subducting direction of Bangong-Nujiang ocean and the subducting period of Yarlung Zangbo ocean and thought that Bangong -Nujiang ocean should subduct southern direction and Yarlung Zangbo ocean should subduct in Early Cretaceous.2. Based on stratigraphic characters and sedimentary suite and magmatic activity, the stratigraphic sub-regions is divided again and the Risong-Jiagang areas where was formerly part of Mugagangri stratigraphic is belong to Risong-Gerze-Taricuo region.3. By the study of lithostratigraphy and biostratigraphy, the suggestion using different names about the Samuluo formations in Bangong lake-Nujiang suture zone, Qiekan-Guchang-Asuo rift zone and between two zones is put forward.4. Based on spatial distribution of the Langshan formation reef in lower cretaceous and Qiekan-Guchang-Asuo rift zone, the viewpoints that Langshan formation reef was mainly distributed along both sides of rift zone is put forward.5.After the detailed study of depositional system and facies, facies sequences and spatio-temporal distribution of depositional system, paleogeographic evolution,更多还原