Rediscussion on Sequence Stratigraphy Standardization: Some Modification Attempt on Base Level Cycle Definition

Song, Laiming

With the development of sequence stratigraphy, people get to know more about the difference between the diverse schools of sequence stratigraphy when solving the production problems. Therefore the multi-theory amalgamation of sequence stratigraphy is one of the most important study fields. There exists distinct difference between water level and base level. The water level is a measurable physical surface and able to be characterized, while the base level is an immeasurable, nonobjective surface and described only. These features of base level lead to the uncertainty of the time scale for the base level cycle and then result in the subjectivity of the sequence stratigraphy. And the rationality of the sequence boundary definition of the base level cycle is questioned. The base level cycle theory must be modified properly to syncretise the other sequence stratigraphy theories according to the production situation of oilfields and the subject development. We think that the only way to solve the inconsistency between the classic and high-resolution sequence stratigraphy is to redefine the base level cycle. In the end the suggestion is made that a base level cycle be a set of formation deposited from the descending to ascending stage of the base level instead of from its ascending to descending stage. With this idea we discuss the stratigraphic correlation of Gaoshangpu oil field and BZ oil field. The result shows that the idea can deal with the development problem to a great extent.

AAPG Search and Discovery Article #90163©2013AAPG 2013 Annual Convention and Exhibition, Pittsburgh, Pennsylvania, May 19-22, 2013