Lying in the east of Heilongjiang province, Yishu graben is a Cenozoic fault basin comprising two large second-class structural units, i.e., Tangyuan and Fangzheng fault basins.

• 摘要依舒地堑位于黑龙江省东部，为-新生代断陷盆地，汤原断陷和方正断陷为其两个面积较大的二级构造单元。