The core of Yanchang Formation Chang-7 high quality source rock (oil shale) is black,hard,light,and it looks slip-shape after demorphism.

• 鄂尔多斯盆地延长组长7优质烃源岩(油页岩)井下岩芯外观呈黑色、质硬、手感较轻,露头风化后呈纸片状。