Fluvio-hydrological characteristics and diverse bedrock geology control the dynamic growth,truncation,and amalgamation of bedrock streambed and marine potholes  

作　　者：Biswajit Bera Sumana Bhattacharjee Uttam Mukhopadhyay Debasis Sengupta Pravat Kumar Shit Nairita Sengupta Supriya Ghosh Arijit Ghosh Soumik Saha Sudipa Sarkar 

机构地区：[1]Department of Geography,Advanced Geomorphology and Hydrology Laboratory,Sidho-Kanho-Birsha University,Purulia,West Bengal,India [2]Department of Geography,Jogesh Chandra Chaudhuri College(University of Calcutta),Kolkata,India [3]Department of Geography,Vidyasagar College,University of Calcutta,Kolkata,West Bengal,India [4]Department of Geology and Geophysics,IIT,Kharagpur,India [5]PG Department of Geography,Raja Narendra Lal Khan Women's College(Autonomous),Vidyasagar University,Midnapore,India [6]Department of Geography,Diamond Harbour Women's University,Sarisha,India

出　　处：《River》2025年第1期84-105,共22页江河(英文)

摘　　要：A total of 393 potholes(368 fluvial and 25 marine potholes)were studied at seven different sites in both the fluvial and marine environments.Diverse bedrock properties and large-scale delivery of tools and grinders regulate the dynamic growth,truncation,and amalgamation of potholes.Therefore,the principal objectives of the study are(i)to examine the relationship between the growth of potholes and substrate lithological with structural characteristics(applying geospatial and Schmidt hammer for rock strength analysis)and(ii)to measure the morphology,and size of tools and grinders,processes of truncation and amalgamation in hydro-geomorphic environment using various indices and field techniques.The result showed that large potholes are stretched in the direction of lineament axes and roughly parallel to the river flow direction.Here,the steady growth of pothole depth-diameter is controlled by active bedrock structures,tools,or grinders,and monsoonal high-velocity bank full discharge.Consequently,the deepening and widening of potholes are relatively slow at Bindu,Deuli,and marine beach Neil Island due to fewer structures and little supply of tools or grinders.In small stretches,(Damodar,Subarnarekha,and Rarhu)canyons and gorge-like features(bedrock incision)are formed at Rajrappa,Bhakuyadi,and Guridih sites due to cyclic truncation and amalgamation.Truncation and amalgamation processes restrict the vertical depth threshold value of potholes within 3m,particularly at Rajrappa,Bhakuyadi,and Guridih sites.Scientific study of the pothole's dynamic growth is greatly necessary for the different environmental engineering and river hydraulic projects like excavation,dredging,and dam or barrage construction.Successively,it is essential to compute the cost of rock excavation or dredging,primarily for the mechanical strength of the bedrock river channel and its stability.

关 键 词：bedrock structures rock strength Schmidt hammer rebound values toolsand grinders truncation and amalgamation 

分 类 号：F76[经济管理—产业经济]