The Geology of the Grand Canyon 网址：

来源: 美语世界 于 2007-07-13 05:25:37 [] [博客] [旧帖] [给我悄悄话] 阅读数 : (194 bytes)
本帖于 2007-07-15 04:26:33 时间, 由版主 林贝卡 编辑

How was it formed?

Where did all the rock come from?

Why does it look like it does?

When did all this happen?

http://www.bobspixels.com/kaibab.org/geology/gc_geol.htm

请您先登陆，再发跟帖！