断陷湖盆陆相层序中高频层序的米氏旋回成因探讨  

Discussion on Milankovitch Orbit Cycle in High Frequency Sequence of Terrigenous Sequence in Fault-depressed Lacustrine Basin

作　　者：胡受权[1] 郭文平[2] 

机构地区：[1]中山大学地球科学系,广东广州510275 [2]中山大学城市与区域研究中心,广东广州510275

出　　处：《中山大学学报（自然科学版）》2002年第6期91-94,共4页Acta Scientiarum Naturalium Universitatis Sunyatseni

基　　金：广东省自然科学基金资助项目 (994 113) ;国家"油气藏地质及开发工程"重点实验室开放基金资助项目(PLN992 2 )

摘　　要：以泌阳断陷湖盆下第三系核三上段为例 ,通过单井高频层序分析 ,将其划分出 3个层序 9个体系域 ,发育 4类 13个小层序组 ,其中可识别的小层序达 5 0多个 ;采用滤波技术和傅里叶变换 ,对单井自然电位 (SP)测井曲线进行技术处理 ,获取其沉积旋回曲线和频谱曲线 ,以了解优势旋回的分布及旋回时限。研究结果显示 ,泌阳断陷湖盆的高频层序是由米氏旋回所驱动的古气候周期性波动所形成的。亦即 ,古气候是影响陆相层序发育的一个重要因素 ,其周期性变化是源于米氏旋回的驱动力 (即米兰柯维奇天文旋回 )。米兰柯维奇天文旋回包括偏心率旋回、倾斜率旋回和岁差旋回 ,这几个轨道参数所驱动的古气候变迁 ,分别形成了周期为 10万a (或4 0万a)、 4万a及 2万a的高频层序 ,即小层序组、小层序及小层单元。A case study of the upper member of Eh 3 in Biyang fault_depression is conducted. By singal well analysis of high frequency sequence, the upper member of Eh 3 of Biyang fault_depression can be classified into three terrigenous \{sequences\} and nine systems tracts,or into four basic types and thirteen parasequence sets, of which there are fifty recognizable parasequences. Using SP log curve treated with mathematical transformation, the sedimentary cyclicity curve and spectral curve can be obtained to find out characterictics of dominant cyclicity. The research results show that high \{frequency\} sequences in Biyang fault_depression were controlled by paleoclimatical cyclic transformation, which was caused by Milankovitch orbit cycle. Milankovitch orbit cycle consists of accentricity, inclination and procession of equinoxes which lead to palaeoclimatical cyclic transformation and form high frequency sequence, namely parasequence sets,\{ parasequence,\} and beds with cycles of 1×10 5,4×10 4,2×10 4 years,respectively.

关 键 词：米氏旋回 高频层序 频谱分析 沉积旋回 陆相层序 断陷湖盆 古气候 形成原因 

分 类 号：P539.2[天文地球—古生物学与地层学]