Denuded by the Indochina movement, the core of the palaeohigh has no cap rocks like the J4 gyprock.

古隆起曾遭受早印支运动强烈的剥蚀，已无嘉四段良好的膏岩作盖层。

Duiker, William J. U.S. Containment Policy and the Conflict in Indochina. Stanford: Stanford University Press, 1994.

著，《美国围堵政策和中南半岛的冲突》，：大学出版社，1994年。