鲁北平原第四纪古地理的演变

QUATERNARY PALAEOGEOGRAPHIC EVOLUTIONS OF NORTHERN SHANDONG PLAIN

本文根据大量钻孔资料的研究,论述了鲁北平原自晚第三纪末期以来第四纪各时段岩相古地理的发展与演变,如火山活动、海侵与海岸线的变迁、湖泊的消长、河流的分布与变迁、冲积相和冲、洪积相的分布范围与变化等.

This paper studies lithofacies-palaeogeographic evolutions of Quaternary(1.8 Ma. B. P. ), based on a number of drilling data from the northern Shandong plain. The northern Shandong area was lifted and then eroded by neotectonic movements in Pliocene and early Pleistocene. Only in the central depression area were deposited fluvial-lacustrine sediments. In late early Pleistocene, the plain began to subside wholely and accept sediments and was frequently intruded by sea water, after the Dashan basalt erupted. In late Pleistocene, the Yellow River entered the plain, thus the sedimen-tary rate became much greater and sedimentation province was expanded. In late late Pleistocene and Holocene, the neotectionic movement continu-ously lifted the mountains, the mountain marginal areas did not accept depo-sition except in vallays and basins, while the plain has been subsiding.