hard shale formation

thin interbedded sandstones-shale formation

shale-free formation

burgess shale shale

oil shale and oil shale residue

Member 4 of Quantou Formation -Yaojia Formation

Qingshankou Formation-Yaojia Formation

the 2nd Member of Shanxi Formation—the 8th Member of lower Shihezi Formation

Abnormally Pressured Shale

active soft shale

Agrillaceous shale

Albert shale

alkali leach liquor of carbonaceous shale containi

Alkali Leach Liquor of Carbonaceous Shale Containing Vanadium

alum shale

alumina shale

aluminous shale

angular shale

areaceous shale