The basin tectonic model: it is intermont basin during late Jurassic to early Cretaceous, developed into faulted-lacustrine basin in Eogene, and evolved into depression in Neogene and Quaternary.
“”构造发育模式为:从晚侏罗世到白垩纪末期发育
山间“
”开始、发展到早第三纪断陷湖
发育、再演化为晚第三纪及第四纪
陷发育阶段。