一种确定沉积旋回类型的迭代算法

An Iterative Algorithm for Determining the Type of Deposition Cycles

层序地层学中沉积旋回产生地层旋回,只有在充分了解沉积旋回的基础上才能准确解释地层旋回样式,而沉积旋回是沉降速率B、沉积速率D和侵蚀速率E组合的结果,且旋回的形态受到8个基本点的控制。利用一种迭代算法确定了这些基本点的位置,模拟出基准面、沉积面、沉积厚度、剩余可容纳空间、旋回比例等参数在一个基准面旋回期间的变化规律,并将这些变化对应不同沉积阶段,对已经确定的层序样式进行反演,反演的结果能够确定出在最大侵蚀速率E一定的情况下与构成这种层序的相应的B、D组合,从而实现对地层层序模式的定量化研究。

Stratigraphic cycle was produced in sediment cycle only on the base of knowing sedimentation cycle, the form of stratigraphic cycle was interpreted,sedimentation cycles were produced for all combinations of subsidence rate(B), limiting deposition rate(D) and limiting erosion rate(E),the form of the cycle corresponding to any given combination was defined by eight points. The position of these points were readily determined by using a straight forward iterative algorithm,each point was adjusted in turn until the stable cycle form was reached. The change rules of parameters were simulated in a base-level cycle period for base level,sedimentation surface,sediment thickness, accommodation space and cycle proportion; and correspond these changes to different stages of deposition. For a particular type of sequence in a periodicity of base-level cycle, style sequence can be inverted in this paper.The result of inversion can ascertain the combination of B(subsidence rate), D(limiting deposition), E(limiting erosion rate) which constitutes to the sequence, so it realizes the quantitative research for stratigraphic sequence.