摘要
选择黔西地区盘1井、威宁1井、纳雍1井和织金1井,对长兴组自然伽马测井数据进行频谱分析,识别出其中的米兰科维奇周期,并采用滤波手段提取出其中的稳定周期,进行连井对比。结果表明频谱峰值与米兰科维奇周期存在良好的对应关系,研究区长兴组地层中保存着123. 0 ka的偏心率周期、45. 0 ka和35. 6 ka的斜率周期、21. 2 ka和17. 7 ka的岁差周期,各级周期的旋回厚度分别为4. 59~5. 73 m、1. 37~2. 15 m和0. 66~0. 98 m;各井的短偏心率旋回曲线显示研究区长兴组地层记录了约18个短偏心率旋回,据此估计出长兴组沉积时限约为2. 21 Ma;通过短偏心率旋回层和所计算沉积速率的连井对比,发现地层中海相标志岩层段等时性对比效果明显,反映了区域快速海侵的过程,而沉积速率的变化可能受到了海平面变化和物源供应的共同影响。
Spectral analysis was conducted on the natural gamma ray logging data from the Changxing Formation of the wells Pan 1,Weining 1,Nayong 1 and Zhijin 1 in western Guizhou. Major Milankovitch sedimentary cycles are identified,and the stable periods are extracted using the filtering method for the contrasts of well connection. The results show good correlations between spectral peaks and Milankovitch cycles,and it is suggested that the Changxing Formation in the study area has preserved the eccentricity cycle of 123 ka,the obliquity cycles of 45 ka and 35. 6 ka,and the precession cycles of 21. 2 ka and 17. 7 ka. The average stratigraphic thickness of all cycles is 4. 59 to 5. 73 m,1. 37 to 2. 15 m and 0. 66 to 0. 98 m,respectively. The short eccentricity cycle curve of each well shows that about 18 eccentricity cycles are recorded in the Changxing Formation,which indicate that the diagenesis of the Changxing Formation can be estimated as 2. 21 Ma. Based on the well connection contrasts of the short eccentricity cycle layers and the calculated sedimentation rate,it is found that the isochronic contrast effect of the marine facies marker sequence is distinct,which reflects rapid regional transgression,while the change of sedimentation rate may be affected by the sea-level change and the sedimentary supply.
作者
王燕
袁学旭
郭英海
沈玉林
WANG Yan;YUAN Xuexu;GUO Yinghai;SHEN Yulin(State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences,Beijing 100083,China;School of Safety Engineering,North China Institute of Science and Technology,Beijing 101601,China;School of Resource and Earth Science,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China)
出处
《现代地质》
CAS
CSCD
北大核心
2019年第3期598-603,共6页
Geoscience
基金
国家科技重大专项(2016ZX05044-002-001)
国家自然科学基金项目(41672146)
中央高校基本科研业务费项目(3142018005)
山东省沉积成矿作用与沉积矿产重点实验室开放基金(DMSM2017017)
关键词
黔西地区
长兴组
米兰科维奇旋回
自然伽马测井数据
western Guizhou
Changxing Formation
Milankovitch cycle
natural gamma ray logging data
