摘要
柴达木盆地保存了巨厚的完整连续的新生代沉积层序,为研究沉积旋回提供了良好的场所。位于盆地西部尕斯地区的上干柴沟组是典型的陆相碎屑岩地层之一,由多层砂岩和泥岩频繁相互叠置而成,高精度的沉积旋回研究鲜有讨论。综合运用频谱及滤波方法来深入分析地处柴西尕斯地区的YP2、YQ17井自然伽马测井数据。结果显示,天文轨道周期比值和中高频旋回厚度之间比值的对应性相对较好。在此基础上结合沉积速率及古气候两个方面的因素进行讨论,发现尕斯地区上干柴沟组的地层中保存了较为完整的米兰科维奇旋回。其中,短偏心率周期引起的地层旋回厚度变化为10.48~11.26 m;轴斜率长周期引起的地层旋回厚度变化为5.85~5.87 m;轴斜率短周期引起的地层旋回厚度变化为4.22~4.57 m;岁差长周期引起的地层旋回厚度变化为2.42~2.61 m;岁差短周期引起的地层旋回厚度变化为1.97~2.12 m。
The thick and complete Cenozoic sedimentary sequences are preserved in the Qaidam Basin,which provides a good place for studying the sedimentary cycle.The Shangganchaigou Formation distributed in the Gasi area in the west of the basin,and is one of the typical continental clastic strata,which is composed of multi-layered sandstone and mudstone in superposition of each other frequently.However,there is little discussion about its high precision sedimentary cycle.Therefore,the spectrum and filtering methods were comprehensively used to analyze the natural gamma logging data of Well YP2 and Well YQ17 in the Gasi area of the western Qai-dam Basin.The results show that there is a good correspondence between the ratio of the astronomical orbital period and the ratio of the thickness of medium and high-frequency cycles.On this basis,combining the factors of sedimentary rate and paleoclimate,the Milan-kovitch cycle is relatively complete in the Shangganchaigou Formation in Gasi area.Among them,the thickness variation of the formation cycle caused by the short eccentricity period was 10.48~11.26 m,that caused by the long period of the obliquity was 5.85~5.87 m,that caused by the short period of the obliquity was 4.22~4.57 m,that caused by the long precession period was 2.42~2.61 m,and that caused by the short precession period was 1.97~2.12 m.
作者
唐闻强
伊海生
陈云
张承志
泽仁拉姆
邢浩婷
TANG Wen-qiang;YI Hai-sheng;CHEN Yun;ZHANG Cheng-zhi;ZEREN Lamu;XING Hao-ting(Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China;No.1 Oil Producing Plant of Qinghai Oil Field,CNPC,Dunhuang 736202,China;State Key Laboratory of Oil/Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,China;College of Earth Sciences,Chengdu University of Technology,Chengdu 610059,China;Institute of Exploration and Development of Qinghai Oil Field,CNPC,Dunhuang 736202,China)
出处
《科学技术与工程》
北大核心
2021年第11期4360-4368,共9页
Science Technology and Engineering
基金
国家自然科学基金(41902107)
中国石油重大科技专项(2016E-0104GF)。
