陆丰、惠来地区第四纪沉积物粒度、微体古生物与沉积相分析及其对古环境的指示意义  

Grain Size,Microfossil,and Sedimentary Facies Analysis of Quaternary Sediments in Lufeng and Huilai Regions,as well as Their Indications for Paleo-Environment

作　　者：许冠军 吴梓源 龙桂 方梓彬 陈浩权 唐海燕 陈禹聪 刘岳昕 涂华 赖忠平 XU Guanjun;WU Ziyuan;LONG Gui;FANG Zibing;CHEN Haoquan;TANG Haiyan;CHEN Yucong;LIU Yuexin;TU Hua;LAI Zhongping(Guangdong Geological Survey Institute,Guangzhou 510080,Guangdong,China;Institute of Marine Science,Shantou University,Shantou 515063,Guangdong,China)

机构地区：[1]广东省地质调查院,广东广州510080 [2]汕头大学海洋科学研究院,广东汕头515063

出　　处：《汕头大学学报（自然科学版）》2024年第1期31-43,共13页Journal of Shantou University：Natural Science Edition

基　　金：广东省地质勘查与城市地质专项(2022-18,2023-15,2023-22)。

摘　　要：粤东地区是研究华南沿海地区古地貌变迁及海陆相互作用的重要窗口.本文提供了汕尾及揭阳惠来地区实测沉积物粒度组成数据和微体古生物组合数据,为进一步开展该区域第四纪研究提供了基础资料.微体古生物鉴定结果表明,样品中所含的有孔虫、介形虫和硅藻化石均属于第四纪常见种.综合结果表明,陆丰钻孔LFZK05和惠来钻孔HLZK02的岩芯中可能存在三个海相层,说明汕尾陆丰和揭阳惠来地区在第四纪以来至少经历过三次海侵.推测最年轻的海侵层沉积于全新世.该全新世海侵层见于陆丰螺河沿岸的钻孔LFZK04中,但在更为上游的钻孔LFZK03中却没有发现,这可能说明汕尾陆丰地区全新世海侵范围没有到达钻孔LFZK03(自海岸线沿螺河上游约10 km处)的位置;但也不能排除钻孔LFZK03之前存在的海侵层被河流活动侵蚀而未能保存的可能性.上述推论需要结合年代数据进一步厘定.本文提供了汕尾及揭阳惠来地区第一批发表的沉积物粒度分布数据和微体古生物数据,为进一步开展该区域第四纪研究提供了基础资料.Lufeng and Huilai regions are important windows for studying paleo-geomorphic changes and terrestrial-marine interaction in the coastal South China.In this research,coring and sampling work was carried out in six sites in the Lufeng and Huilai regions,and grain size distribution data of different cores and the microfossil data of two representative cores(HLZK02 and LFZK07)were obtained.By combining lithology,grain size analysis,and microfossil analysis,the sedimentary facies of each core were tentatively determined.The results of the microfossil analysis indicate that the foraminifera,ostracods,and diatom fossils found in the samples are common species from the Quaternary period.Comprehensive results suggest that there may be three marine strata in the cores LFZK05 and HLZK02,indicating that the Lufeng and Huilai regions experienced at least three marine transgressions since the Quaternary period.Among them,the latest marine transgression layer was likely deposited during the Holocene,which were observed in the Lufeng LFZK04 but not in LFZK03.This may indicate that the Holocene transgression in the Lufeng Luohe River basin did not reach the location of hole LFZK03(about 10 km from the coastline along the Luohe River).It is also possible that the Holocene transgression layer of core LFZK03 was removed by river activity.The above inferences need to be further determined by combining geochronology.This research flls the gap in sediment grain size distribution data and microfossil data for the Lufeng and Huilai regions,providing valuable information for further Quaternary research in this area.

关 键 词：陆丰 惠来 粒度分析 沉积相 海侵期次 

分 类 号：P67[天文地球—海洋地质]