Abstract:

Deep buried sandstones of Lower Cretaceous in North Songliao Basin are compositionally immature lithic arkose and feldspathic litharenite. The main diagenesis of the sandstones includes:authigenetic clay rim, quartz and feldspar overgrowth, albitization,authigenetic laumontite and the dissolution of feldspar and laumontite. The albitization of anorthosite is the primary mechanism for generating laumontite, whereas the transformation of clay minerals provides sodium and silicon for the precipitation of laumontite.