静力触探在莱州湾冰后期三角洲层序地层学研究中的应用  

The Application of CPT to the Study of Post Glacial Delta Sequence Stratigraphy in Laizhou Bay

作　　者：徐建国[1,2] 刘中业 陶有兵[1,2] 徐华 纪汶龙[1,2] 张春池 XU Jian-guo;LIU Zhong-ye;TAO You-bing;XU Hua;JI Wen-long;ZHANG Chun-chi(Shandong Institute of Geological Survey,Jinan,Shandong 250013;Shandong Technology Research Center of Land Quality Geochemistry and Pollution Prevention Engineering,Jinan,Shandong 250013)

机构地区：[1]山东省地质调查院,山东济南250013 [2]山东省土地质量地球化学与污染防治工程技术研究中心,山东济南250013

出　　处：《地球学报》2022年第1期11-24,共14页Acta Geoscientica Sinica

基　　金：中国地质调查局地质调查项目(编号:1212011220001;12120114033801)资助。

摘　　要：静力触探试验是广泛应用于海岸带地区岩土工程勘察的原位测试手段,静探数据的连续性、高分辨率在其应用于晚第四纪地层结构研究中具有独特的优势。本文对莱州湾沿岸249个工程地质孔-静力触探孔组的岩性编录资料与静探参数资料进行对比研究,建立了冰后期沉积不同沉积相的静探参数曲线识别模式,以此为基础配合^(14)C测年、微体古生物鉴定等资料,开展莱州湾沿岸冰后期三角洲的层序地层学研究,划分体系域、识别层序边界。研究结果表明:(1)莱州湾沿岸晚更新世以来历次海侵均发育河流三角洲,其中的冰后期三角洲保存最完整,区域上分为主体区和侧翼区两个沉积分区,二者在沉积岩性上有明显差异。(2)莱州湾沿岸冰后期沉积体系域类型包括由末次冰盛期至冰后期早期的河流相、滨海湖沼相沉积组成的低水位体系域,由冰后期中期三角洲前缘、潮坪沉积组成的海侵体系域,由冰后期晚期三角洲前缘、潮坪和三角洲平原沉积组成的高水位体系域。(3)莱州湾沿岸冰后期海侵区沉积环境为潮坪环境,整个海侵过程中最大古水深小于10 m。Cone penetration test(CPT)is an in-situ test method that is widely used in geotechnical investigation of the coastal zone.The continuity and high resolution of static sounding data have unique advantages in its application to the study of the Late Quaternary stratigraphic structure.In this study,the lithologic logging data and static sounding parameter data of 249 engineering geological holes and cone penetration test hole groups along the coast of Laizhou Bay were comparatively analyzed,and the identification model of static sounding parameter curve for different sedimentary facies of post glacial sedimentation was established.On such a basis and in combination with^(14)C dating,micropaleontological identification and other data,the sequence stratigraphy of post glacial delta along Laizhou Bay was studied,and system tracts as well as sequence boundaries were identified.This research shows the following phenomena:(1)River deltas were developed in all the transgressions along the Laizhou Bay in the late Pleistocene,and the post glacial deltas were the most well-preserved ones with important research value.The coastal post glacial delta area of Laizhou Bay could be divided into two sedimentary zones:the main area and the flanking area,which are obvious different in lithologic characteristics.(2)In sequence stratigraphy,the post glacia depositional system tracts along the coast of Laizhou Bay might be divided into the following components:low water level system tracts composed of fluvial facies and littoral lacustrine facies deposits from the last glacial maximum to the early post glacial stage,the positive grain sequence transgressive system tract composed of delta front and tidal flat deposits in the middle of post glacial period,and the high water level system composed of delta front,tidal flat and delta plain deposits in the late post glacial period.(3)The sedimentary environment of the post glacial transgressive area along the coast of Laizhou Bay was tidal flat,and the maximum paleo water depth was less than 1

关 键 词：静力触探 冰后期三角洲 粒序结构 层序地层学 古水深 

分 类 号：P539.2[天文地球—古生物学与地层学]