天津南部平原区3.6 Ma以来沉积环境演化——以沧县隆起ZKQ1孔为例  

Sedimentary environment evolution since 3.6 Ma in the southern Tianjin plain--a case study of well ZKQ1 in Cangxian uplift

作　　者：鲁庆伟[1] 詹健[1] 韩芳[1] LU Qingwei;ZHAN Jian;HAN Fang(Geological Institute of North China Geological Exploration Bureau of Tianjin, Tianjin 300170, China)

机构地区：[1]天津华北地质勘查局地质研究所,天津300170

出　　处：《地质找矿论丛》2021年第4期495-501,共7页Contributions to Geology and Mineral Resources Research

基　　金：中国地质调查局项目“天津1:5万静海幅(J50E007012)、唐官屯幅(J50E008012)区域地质调查”(编号:DD20160042-8)资助

摘　　要：沧县隆起是渤海湾盆地的重要构造单元之一,对该区地层长尺度的沉积环境演化分析可为盆地演化、水工环地质勘查以及区域古地理研究等提供基础资料。本文通过对沧县隆起上的ZKQ1孔岩芯详细的沉积特征研究和综合测井、测年(AMS14C、OSL、古地磁)等研究工作,结果表明:①B/M界线位于62.80 m;M/G界线位于130.60 m;钻孔底界年龄不早于3.6 Ma;上更新统、全新统底界分别位于50.30 m、13.10 m。②沧县隆起3.6 Ma以来的沉积环境演化为晚上新世(<3.6—2.58 Ma)由泛滥平原→湖相三角洲→曲流河演变;早更新世以泛滥平原为主,夹湖沼和分支河道;中更新世存在沉积间断;晚更新世—全新世表现为三期河海交互作用沉积演化时期。Cangxian uplift is one of the important structural units in Bohai bay basin.Sedimentary environment evolution of the southern Tianjin plain area for long time scale is analyzed and data obtained can serve hydrogeological exploration and regional paleo geographic research of the area.Combined with comprehensive logging and dating(AMS14C,OSL,Paleomagnetism)sedimentary characteristics of core from well ZKQ1 are detailly studied.The results show that B/M(Brunhes/matoyama)boundary lies at 62.80 m and the M/G(Matuyama/GAUSS)boundary at 130.60 m.Age of bottom sedimentary of the ZKQ1 is dated not older than 3.6 Ma.Upper Pleistocene and Holocene boundaries are at 50.30 m and 13.10 m.Sedimentary environment evolution since 3.6 Ma is flood plain-Lacudtrine delta-meandering river during Late Pliocene(<3.6 Ma-2.58 Ma)and flood plain dominated Early Pleistocene with development of lake and branch channel.During Middle Pleistocene Epoch occurs sedimentation discontinuity,during Late Pleistocene-Holocene,three times of interaction of river and sea.

关 键 词：古地磁 第四系 沉积环境演化 沧县隆起 天津 

分 类 号：P534.63[天文地球—第四纪地质学] P539.4[天文地球—古生物学与地层学]