莱州湾南岸平原浅埋古河道带研究

菜州湾海岸平原在埋深６０ｍ内的浅埋古河道带，可分弥河、潍河和白浪河３个系统，它们大都呈掌状、放射状分布，并与其所属诉冲洪积扇范围相吻合，该区古河道的形成和发育是新构造运动和古气候环境演变的结果。自晚更新世晚期以来，该区有６期古河道发育，其中玉木早冰期古河道和玉木主冰期古河道的砂体沉积粒度粗、连通性好、分布广，即是富水性强、水质好的淡水含水层，又是该区海（咸）水入侵的主要通道，控制在线积粒度粗、连通

A STUDY OF THE SHALLOWLY-BURIED PALEOCHANNEL ZONES IN THE SOUTH COAST PLAIN OF THE LAIZHOU BAY

According to data from more than 2 100 drill holes,lithofacies, 14 C dating of sediments,field investigation,distribution regularities,buried situation and sedimentary characteristics of the shallowly buried paleochannel zones in the south coast plain of the Laizhou Bay, its stage divisions and development laws have been studied.The shallowly buried paleochannel zones within a buried depth of 60 m in the plain can be put under Mihe River,Weihe River and Bailanghe River systems.The shallowly buried paleochannel zones look like a palm in form and are in radial distribution,and correspond with their alluvial diluvial fans.In the plain within a buried depth of 60m,there are 4 stages of paleochannels which have developed since the late period of late Pleistocene,and in which,the paleochannel sand masses of the early and prime Wurm glaciation and in coarse grain size,good continuity and wide distribution,are all aquifers rich in fresh groundwater and the main passageways of salt water intrusion.It is the important measure to prevent from salt water intrusion not to do excessive extraction of fresh groundwater in the shallowly buried paleochannel zones and to recharge groundwater by using the paleochannel zones in the rainy seasons.