Diagenesis of Volcaniclastic Rocks in Hailaer Basin
The microscopic study and analysis of the Cretaceous volcaniclastic samples from 40 drilling wells in Hailaer Basin show that, the speciality of the diagenesis is presented in welding, devitrification and recrystallization, formation and transform of clay minerals and replacement etc. There are three types of welding textures identified as weldings of magma or lava, magma fragment and hot ash. Devitrification and recrystallization were combined. The forming and transforming of clay minerals started early at the initial stage of diagenesis would be products of special diagenesis rather than signs of beginning of metamorphism. The replacement-cementation and dissolution developed well in the volcaniclastic rocks during diagenesis, giving some great changes to the original types of rocks.