The sequence boundaries consist of the first-, second- and third-order sequence boundaries, including transgressive ravinement surfaces and composite exposure-drowning bounding surfaces.

In order to made a study of law of development of side slope gully erosion of highway spoil ground,upgrowth characteristic and law of development of gully erosion and realation between intercolparis erosion and gully erosion had been studied in the spoil ground of constructing Hurongxi expressway of Hubei province.

Administing soil erosion and improving ecology environment are the main measures to solve farmer agriculture and countryside problem at mountainous area and make some good tries and studies,and accumutate some experience for administing erosion gully.

Brief discussion on the formation reason and prevention measure of erosion ditch in plain area;

The causes of forming erosion ditch and main harm to the economic and social development are analyzed in this paper,and the ways and measures of comprehensive prevention and treatment for erosion ditch are put forword in construction projects.