层序地层学:问题与讨论

论文回顾地震地层学对层序地层学的贡献与影响、层序地层学理论积淀，指出沉积层序存在的诸如层序边界（不整合面及其可比的整合面）跨界系统阶等年代地层单位、沉积层序"T-R"水侵-水退建模理论基础与层序边界不断调整、基准面曲线滞后水侵-水退（R-T）曲线和纯几何学的相对应整合面（可比的整合面）禁锢等4个问题.针对4个问题论文建议:（1）静止正常水退（SNR）取代高位正常水退（HNR），解决层序地层学由高位正常水退不合理设定造成的非周期性问题；（2）鉴于残留最大水泛面（RMFS）潜在地接近或一致于年代地层单位界线或全球界线层型剖面和点（GSSP）阶的下界的特征，层序地层学有可能建立残留最大水泛面与其相对应不整合面组成的复合层序边界，其中的残留最大水泛面部分用于解决现行层序边界跨年代地层单位界线的问题；（3）复合层序边界由盆朝陆的"一对一"追踪方式解决层序边界由陆朝盆"一对多"不断调整的问题；（4）降级"相对应整合面"为体系域边界，解决双定义"相对应整合面"问题，其中，Hunt and Tucker（1992）的"相对应整合面"被复合层序边界相对应不整合面部分向盆内延伸（ESU）取代而作为低位体系域底界（ESU亦兼有水侵体系域在不整合处的底界作用），Posamentier and Allen（1999）的"相对应整合面"被复合层序边界之上的恢复的强迫水退底界取代而作为下降期体系域底界.此外，强迫水退底界同义术语现在采用的海相侵蚀海退面（RSME）术语不能全部代表海相与非海相背景. 

Sequence Stratigraphy: Problems and Discussion

This article reviews contributions and influences of seismic stratigraphy to sequence stratigraphy, and theoretical accumulations of sequence stratigraphy; and points four problems as followings:sequence boundaries (subaerial unconformities and their correlative conformies) spanning boundaries of Erathem, System, Series and Stage; "transgressive-regressive" cycles as base of original sequence stratigraphic models inducing to adjust sequence boundaries at least three times, base-level curve delaying transgressive-regressive (T-R) curve, and the purely geometric correlative conformity (c.c) obstructing theoretically sequence stratigraphy. Meanwhile this paper points four aspects as followings. (1) Stillstand normal regression (SNR) replacing highstand normal regression is used to avoid the non-periodicity hiding in sequence stratigraphy due to the unreasonable design of highstand normal regression. (2) Based on the character of remnant maximum flooding surfaces potentially closed to or in accord with the boundaries of chronostratigraphic units or even the lower boundaries of stage (GSSP), sequence stratigraphy is necessary to establish compound sequence boundary composed of remnant maximum flooding surfaces (RMFS) and their correlative unconformities (CSU), and to use the RMFS component to solve the problem that current sequence boundaries have been spanning the boundaries of chronostratigraphic units. (3) It may be applied the one-to-one tracing style (one RMFR to one CSU) from basin to land in compound sequence boundary to the problem that current sequence boundaries have been adjusted many times, i.e., they were placed to base of T-R, base of lowstand systems tract in three-divided model or base surface of forced regression, and top of forced regressive wedge systems tract, due to one-to-many tracing style (one subarial unconformity to many potential correlative conformities) from basin to land in existing sequence stratigraphic models. (4) The term "correlative unconformity" should be reduced to a lower rank as boundary of systems tract so as to solve the problem about "doubly defined correlative conformities" in existing sequence stratigraphic models. Respectively, Hunt and Tucker (1992)'s correlative conformity is replaced by extension of subarial unconformity (ESU) from correlative subaerial unconformity component of compound sequence boundary, and is as base of lowstand systems tract and partially as subarial unconformable base of transgressive systems tract; whereas, Posamentier and Allen (1999)'s correlative conformity is replaced by the resumed term basal surface of forced regression (BSFR) above compound sequence boundary, and is as base of falling stage systems tract. Moreover, regressive surface of marine erosion (RSME) as the synonymous term for basal surface of forced regression does not completely represent marine and nonmarine settings.