现代珠江三角洲前缘生物遗迹组成与分布特征  

Composition and Distribution Characteristics of Biological Traces in the Pearl River Delta Front

作　　者：王媛媛[1] 勾松林 张国成[1] WANG YuanYuan;GOU SongLin;ZHANG GuoCheng(Institute of Resource and Environment,Henan Polytechnic University,Jiaozuo,Henan 454003,China)

机构地区：[1]河南理工大学资源环境学院,河南焦作454003

出　　处：《沉积学报》2024年第5期1512-1529,共18页Acta Sedimentologica Sinica

基　　金：国家自然科学基金项目(42172130);河南省本科高校青年骨干教师培养计划(2023GGJS055)。

摘　　要：【目的】珠江三角洲前缘受河流、波浪和潮汐等因素共同影响,沉积环境复杂,沉积特征丰富,前人大多关注珠江三角洲前缘物理化学沉积特征的研究,然而生物对环境的响应极其灵敏,造迹生物及其产生的生物遗迹在一定程度上反映了研究区内的沉积环境特征。【方法】选取珠江三角洲前缘为研究区,运用现代沉积学及遗迹学方法,通过盐度、粒度、浑浊度分析及X射线计算机断层扫描和计算机重构方法对采取的岩心进行处理,对研究区内不同微环境中的生物遗迹特征进行了精细的研究。【结果】(1)主要造迹生物有双壳类动物沙蚬、节肢动物门寄居蟹、甲壳类动物螃蟹、环节动物门双齿围沙蚕、脊索动物门弹涂鱼等;(2)各微环境生物在层面上营造的生物遗迹主要包括爬行迹、足辙迹、鸟足迹以及排泄迹等,层内的主要遗迹为居住迹,表现为各种类型的潜穴形态如Y型、L型、U型,少量I型;(3)珠江三角洲前缘生物遗迹的分布特征:研究区内现代生物遗迹在水下汊道和岛屿的分异度、丰度及扰动率较分流间海湾高,潮下带位于平均低潮线以下,不便观察。【结论】该研究将补充珠江三角洲前缘的现代沉积学资料,并为三角洲前缘古遗迹学和三角洲前缘古沉积环境重构提供现代实证基础和依据。[Objective]The Pearl River Delta front is a complicated sedimentary system controlled by rivers,waves,and tides.Most previous studies focused on the physical and chemical sedimentary characteristics.However,biogenic sedimentary structures are extremely sensitive to the environment;therefore,comprehensive and high resolution research should be conducted.[Methods]Based on sedimentary and ichnological methods,salinity,turbidity,total organic carbon(TOC),grain size analysis,X-ray scans,and three-dimensional(3D)reconstruction were applied to the modern biogenic sedimentary structures in different microenvironments of the Pearl River Delta front.[Results]The main results are as follows:(1)The main trace makers are Bivalve clams,Arthropoda hermit crabs,Crustacean crabs,Annelid bitoothed berbera,and chordate mudskippers.(2)The main biogenic traces include climbing tracks,foot tracks,bird tracks and excretion tracks,and burrows,and the main morphology of burrows include Y,L,U,and I-shape.(3)The diversity,abundance,and bioturbation in the tidal channel and island are higher than the interdistributary bay[.Conclusions]This study perfected the ichnology of the delta front and modern delta sedimentary environment.Moreover,it resolved the high resolution identification of a paleo-delta front sedimentary system.

关 键 词：现代生物遗迹 遗迹学 三角洲前缘 珠江三角洲 

分 类 号：Q911[天文地球—古生物学与地层学]