【摘要】 楚雄盆地位于扬子板块的西南缘。红河断裂控制盆地的西南边界,断裂走向在该区域发生大角度转折,由华南地区的北西西向变为研究区的北西向,再到青藏高原变为北西西向。中生代以来,除了受到来自西南部的印度板块北移过程中北北东向持续挤压应力外,由于金沙江—红河断裂的存在,并从燕山期以来多次转换、传递来自中国东部滨太平洋构造域的板块向西挤压力。在特提斯构造域近南北方向和滨太平洋构造域近东西向的双重挤压作用力下,盆地内最大主应力方向曾发生近南北和近东西向的多次转变,红河断裂发生左行、右行走滑交替,并伴有盆地内块体旋转。同时,红河断裂的走滑运动和应力传递作用也对盆地挤压变形起到了减弱和缓冲作用。在全盆地地震剖面地质解释基础上,针对楚雄盆地复杂的沉积—构造特征,选择东西向和南北向两条区域大剖面进行平衡剖面构造演化分析,结合盆地区域大地构造背景对楚雄盆地基底形成,以及晚三叠世以来盆地动力机制及伴生的构造演化、沉积迁移、生储盖组合、断裂活动、火成岩分布和油气运聚条件进行分析。认为:①盆地内自中生代以来最大主应力方向发生多次改变,控制了构造迁移、盆地内生储盖组合分布及厚度、断裂特征和油气运聚的联动效应;②火成岩分布与基底深大断裂的分布密切有关,今后勘探中应注意基底大断裂的识别;③盆地内西部坳陷具有烃源岩分布面积广、厚度大、盖层厚、泥质含量高、密封性好的特点,有利于大量油气生成和保存,尤其是西部坳陷中部轴向呈南北—北西延伸的长期继承性坳中隆褶带,是下步优先勘探领域。更多还原

【Abstract】 Chuxiong Basin is located at the southwest margin of Yangtze tectonic plate.The Red River fracture controls the southwest boundary of the Basin with a high angle transition from NWW in the southeast to NW of study area,then NWW again in the Qinghai-Tibet Plateau.Maximum principal stress orientation in the Basin has changed several times since Mesozoic from nearly SN to EW,the Red River fault has undergone left-lateral or right-lateral strike-slip movement,accompanied by internal block rotating,due to the continuous NNE compression stress generated by the Indian Plate movement from southwest to northeast,the existence of Jinsha River-Red River fracture,and the westward compression stress transferred from the Marginal-pacific tectonic domain east of China.The strike-slip movement and stress transfer of Red River fracture also cushion the extrusion deformation of the Basin.Base on the seismic interpretation of the whole Basin,in view of the complex depositional-tectonic characteristics of the Basin,this paper selects two regional seismic profiles of SN and EW orientations for tectonic evolution analysis with balanced-section technique,then analyzes the basement formation of the Basin,the dynamic driving mechanism and its derivative tectonic evolution,depositional migration,source-reservoir-cap rock assemblages,fault activities,igneous rock distribution and the condition of hydrocarbon accumulation since Late Triassic,on the basis of the regional tectonic background.It is concluded that:①The maximum principal stress orientations have changed several times in the Basin since the Mesozoic Era,and controls the linkage effects among tectonic migration,distribution and thickness of source-reservoir-cap rock assemblages,fault features and hydrocarbon accumulation;②The distribution of igneous rocks relates closely to the distribution of basement fractures,so much attention should be paid to the recognition of large basement faults in future exploration;③Source rock in western depressions of the Basin features in wide distribution,high thickness,thick cap rock,high shale content,and good sealing property,which is favorable for hydrocarbon generation and preservation.In particular,the long-term successive evolution structural belts or traps with SN-NW trends would be the prospecting domains of priority for further exploration.更多还原