摘要
采用测井钍钾比指标的频谱分析方法识别出川东渝北下三叠统飞仙关组中的米兰克维奇周期 ,并认为其中的离心率周期表现较强 ,控制了飞仙关组的基准面旋回和沉积变化。尝试将飞仙关组划分为 5 6个短离心率旋回 ,每个周期约 1 0万年 ,厚度约 3～ 1 5m ,可为飞仙关组地层区域等时精细对比提供了一种基础依据。
Spectral analysis based on thorium to kalium ratio logging indicates that there are Milankovitch Cycles existing in the carbonate rock in Feixianguan formation of northeast Sichuan Basin. Among these cycles the orbital forcing eccentricity cycles, which controlled the deposition and base-level changes of Feixianguan formation in this area, are shown more prominently. 56 short eccentricity cycles have been identified in this formation, 0.1 million years in length and 3-15 meters in thickness for each. These eccentricity cycles can act as chronologically fine formation correlating basis, remarkably improving the accuracy of stratigraphic correlation of this formation.
出处
《天然气勘探与开发》
2004年第1期16-19,共4页
Natural Gas Exploration and Development
关键词
飞仙关组
米兰科维奇理论
钍钾比
离心率
频谱分析
基准面
地层划分
周期
Milankovitch theory, spectral analysis, eccentricity cycle, base level, Feixianguan Formation, thorium to kalium ratio
