东营凹陷早第三纪古气候变化对层序发育的控制

依据东营凹陷下第三系地层中的孢子、花粉资料，用ＲＱ型因子分析方法对其古气候特征进行了恢复。结果表明，干旱气候背景下东营凹陷下第三系的气候周期性变化与湖盆中的层序发育有良好的对应关系。气候的周期性变化导致湖盆中湖平面的变化，从而控制并发育了具有低水位、湖泊扩张、湖泊收缩和高水位体系域的气候层序。这种气候层序与海相层序具有相似的层序发育控制因素、体系域组成和水平面变化规律，但它的分布范围和层序厚度都比海相层序小。

/ EFFECT OF PALEOCLIMATE ON SEQUENCE DEVELOPMENT AT DONGYING SAG IN EARLY TERTIARY

Paleoclimate was restored by using the method of R Q mode according to pore pollen combination data from the formations at Dongying sag in early Tertiary. It shows that periodic change of climate under the background of draught is correlated with the development of sequence in lacustrine. Periodic change of climate leads to lake level change in lacustrine, and then controls the formation of climatic sequence which is composed of Lacustrine lowstand system tracts, Lacustrine extension system tracts, Lacustrine highstand system tracts and Lacustrine contraction system tracts. Comparing to marine sequence, climatic sequence has the similar controlling factors for sequence development, compositions of system tracts and laws of water level change to marine sequence. The distribution range and thickness of climatic sequence are smaller than those of marine sequence.