โดย ผู้ช่วยศาสตราจารย์ สมบัติ อยู่เมือง
ศูนย์วิจัยภูมิสารสนเทศเพื่อประเทศไทย จุฬาลงกรณ์มหาวิทยาลัย [ GISTHAI ]
e - mail : ysombat@chula.ac.th

Abstract
     It has been evident for years that several organizations have constructed various types of benchmarks as to indicate subsiding areas in Bangkok Metropolis. In 1992, there were about 1,200 benchmarks, which was constructed by the Royal Thai Survey Division (RTSD), Department of Mineral Resources (DMR), Bangkok Metropolitan Administration (BMA) and National Environmental Board (NEB), scattered throughout Bangkok Metropolis.
     This study aims at compiling and presenting three-dimensional models of land subsidence during 1990 to 1997 by applying the secondary data from Department of Mineral Resources (DMR), Royal Thai Survey Department (RTSD), Bangkok Metropolitan Administration (BMA) and National Environmental Board (NEB). Synthesized by Geographic Information Systems softwares, namely, Arc View GIS and Arc View 3D Analyst, the model will clearly demonstrate significant land subsiding areas year by year. Through this means, land subsidence in Bangkok Metropolis can be estimated and monitored interactively corresponding to environmental management in the future, such as groundwater or flood control and so on.