Neoproterozoic Diamictite of the Luoquan Formation from the North China Block and Their Implications  

作　　者：Peishan Sui Weidong Sun Nan Han Lei Wang Shiwen Xie Zihang Huang Xiaohong Wang Hongmei Gong Jin Liu Jinyan Lin Yuanyuan Xiao 

机构地区：[1]CAS Key Laboratory of Marine Geology and Environment,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China [2]Laboratory for Marine Geology,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266061,China [3]College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,China [4]Center for Ocean Mega-Science,Chinese Academy of Sciences,Qingdao 266071,China [5]Center of Deep-Sea Research,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China [6]Changqing Oilfield Exploration and Development Research Institute,Xi'an 710018,China [7]Yanchang Oilfield Exploration and Development Technology Research Center,Xi'an 716001,China [8]Beijing SHRIMP Center,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China [9]Public Technology Service Center,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China [10]Department of Geology,Northwest University,Xi'an 710069,China

出　　处：《Journal of Earth Science》2023年第4期1128-1139,共12页地球科学学刊（英文版）

基　　金：supported by the National Natural Science Foundation of China (Mos.41776069 and 41572047 to Yuanyuan Xiao);Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDB42020302);the Taishan Scholar Program of Shandong (No.ts201712075);Aoshan Scholar Program of the Pilot National Laboratory for Marine Science and Technology (Qingdao) to Weidong Sun。

摘　　要：Glacial diamictite may provide important information on paleoenvironment and average composition of the upper continental crust(UCC).In this study,we report sedimentary facies,petrological and geochemical characteristics of Neoproterozoic diamictite from a profile of the Luoquan Formation on the southern margin of the North China Block(NCB).Upwards the sampling profile,lithostratigraphic strata vary from massive diamictite with poorly sorted carbonate gravels to laminated diamictite with small gravels of terrestrial detrital materials.Along the profile,CaO-MgO-LOI-Sr values decrease with the increase of SiO_(2)-Al2O_(3)-K2O contents.All these petrological and geochemical variations indicate a change from lodgement till deposition in the proximal of ice sheet to ice-rafting deposition in glacial-marine environment with less dolomite to supply their source.Together with previous studies on diamictite from other outcrops on the NCB,the deposition of Luoquan diamictite reflects that the glaciation on the NCB vanished and the ice-rafting effect weakened with glacial transgression process.In addition,significant co-variations of various elements with La and Al2O_(3)confirm the significant conservation of most analyzed elements during the sedimentary processes to produce diamictite.

关 键 词：DIAMICTITE North China Craton PALEOENVIRONMENT the Luoquan Formation Neopro-terozoic sedimentation. 

分 类 号：P618.13[天文地球—矿床学]