辽东半岛长兴岛八岔沟古泻湖型泥炭的形成及全新世最高海平面  

Paleoenvironments of Holocene Lagoon Peat and the Highest Sea-Level in Bachagou,Changxing Island,Liaodong Peninsula

作　　者：方晶[1,2] 胡克[1] 杨永强[1] 柴锐[2] 李东涛 倪金 康玲玲[2] 李瑞武 武亚芳[1] 马楠 

机构地区：[1]中国地质大学海洋学院,北京100083 [2]天津师范大学城市与环境科学学院,天津300387 [3]辽宁省地质矿产调查院,沈阳110032 [4]甘肃省张掖市山丹县霍城镇霍城中学,甘肃张掖734100 [5]天津市第十九中学,天津300020

出　　处：《吉林大学学报（地球科学版）》2009年第3期461-469,共9页Journal of Jilin University：Earth Science Edition

基　　金：国土资源部大调查项目(1212010540502)

摘　　要：通过对辽东半岛西部的长兴岛八岔沟古泻湖平原进行钻孔调查取样，对由海向陆4个不同地点的100余个钻孔样品，进行粘土混浊水导电率测定，区分了八岔沟古泻湖平原的海陆相沉积层，查明了该古泻湖平原的海相层上限的高度。结果表明：该平原各孔的海相层上限高度具有明显的一致性，大约为海拔4．0～4．2m，此高度代表了该古泻湖平原全新世最高海平面期间海水所达到的平均高潮线的高度。通过测定和讨论覆盖在海相层上的泥炭底部^14C年代，明确了该区略早于5800cal．aB．P．达到全新世最高海平面。全新世最高海面期的平均海平面高度约为海拔3．4～3．6m。将此高度与辽东半岛东部大孤山一带的全新世高海平面期（6000-5500 cal.aB．P．）的平均海平面的高度值约2m相对比，显示出在全新世期间辽东半岛西部八岔沟一带较东部的大洋河平原有相对上升的趋势。深达9m的B3孔的导电率有两个高峰值，反映该平原全新世曾发生过两次海侵，较晚一次海侵的最大范围达到距现代海岸线约1．2km处。Through samples drilling survey of the ancient lagoon in the western Changxing Island of Liaodong Peninsula, over 100 boreholes samples from 4 different locations from sea to land are being tested for clay turbid water electric conductivity to distinguish the sediments of the land and sea facies of the ancient lagoon plain and to identify the upper bound of the ancient marine layer. The result shows that the upper bounds at different drilling holes are consistent and are about 4.0 -4.2 m above sea level,and this level could represents the average high tide line of the highest sea level of the Holocene lagoon plain. By ^14C measurement of the basal peat covering the marine layer, it is suggested that the highest sea-level of Holocene was seen at about 5 800 cal. aB. P. The average sea level of at highest sea-level periods of the Holocene is about 3.4 -3. bout 2 m） of the high sea level in the 6 m. When this height is compared with the average sea-level （aeastern part of Dagushan of Liaodong Peninsula, it seems there was a rising at the Bachagou area of the western Liaodong Peninsula. In addition, there are two peaks in the conductivity measurement profile in 9 m deep B3 hole, reflecting two transgressions during Holocene. The largest range of later transgression is up to about 1.2 km away from the modern coastline.

关 键 词：粘土混浊水导电率 古泻湖平原 泥炭层 全新世 辽东半岛 

分 类 号：P534.632[天文地球—第四纪地质学]