摘要： 在层序地层学的Exxon时代,在强调陆上不整合面形成层序界面的概念体系中,科学家们总结认为,陆相层序形成在基准面上升期间,以一个从聚合的河道相砂岩到孤立的河道相砂岩组成的向上变细的沉积序列为特征,这代表了一个重要的概念进步;但是,运用海相层序地层的“体系域”名称,如海侵体系域和高水位体系域等,来划分和解释陆相层序的时候,又产生了若干的概念体系不协调。基于此,产生了陆相层序体系域构成的“非常规”体系域概念,成为陆相层序研究的第2个概念进步。更为重要的是,与海相地层一样,主要的沉积作用发生在基准面上升期间,但是,在基准面下降期间也可能产生相应的沉积,从而进一步说明了陆相地层复杂的堆积作用和响应机制,也表明了陆相层序更多的变化性。陆相层序的上述特征成为近年来关注的焦点之一。追逐这些概念变化和进步,将有益于深入理解陆相层序复杂的形成过程而具有重要的科学意义,同时也代表了层序地层学研究的一个重要进展。

关键词: “, 常规”, 体系域, “, 非常规”, 体系域, 陆相层序, 层序地层学, 研究进展

Abstract: During the Exxon Time for sequence stratigraphy,as the first important conceptual progress,it was proposed that the continental sequence is usually formed in a rising period within a base-level changing cycle under the conceptual system of the subaerial unconformity that makes up the sequence boundary. The continental sequence is characterized by amalgamated and isolated fluvial channel sandstones, with grain size fining upward. However,there are many conceptual inconsistencies for the continental sequence stratigraphy especially for the division of system tracts,such as the transgressive system tract or the high-stand system tract,which were resulted from the interpretation of marine “conventional”system tracts. The “unconventional”system tracts for the continental sequence are established under this situation,i.e. the high accommodation and the low accommodation system tracts,which might represent the second conceptual advancement of the continental sequence stratigraphy. More importantly,although the major sedimentation occurred during the ascending period of base-level like marine strata,deposits may be formed within the descending period of base-level,which further reflects the complicated sediment accumulation and its response mechanism of a continental sequence,as well as its variability. The characteristics mentioned above have become one of the focal points in recent years.It is very meaningful for tracing both the changes and progresses of the conceptual systems for the continental sequence stratigraphy,and is very favorable for further understanding of the sophisticated forming process of the continental sequences,which represents a significant advancement on the study of sequence stratigraphy.

Key words: “conventional”, system tracts, “unconventional”, system tracts, continental sequence, sequence stratigraphy, research advancement

中图分类号: 

• P539.2