中文摘要：

以嘉定中心城镇为例，对四个时相的TM影像进行处理，结合统计资料，分析了1989年--2006年该区域城镇扩展过程中土地利用数量变化情况、城镇形态变化情况及其驱动力因素，为研究中小城镇扩展提供实证依据。

英文摘要：

It makes the center Jiading district as an example, through processing of the four-phase TM images information combined with statistical information on the 1989--2006 years, in order to find out the land use changes of the urban expansion in the quantity, morphological changes and the urban expansion＇s driven factors, and provides an empirical basis for the study of expansion of medium and small towns.