THE S IGNIF ICANCE OF THE SOLUTION OF FELDSPAR IN POROSITY DEVELOPMENT 1

ABSTRACT: Post-depositional solution of feldspar is an important process in porosi W development in some formations. Solution is very selective and may result in considerable reduction in the amount of feldspar and signi:Hcant change in proportion of feldspar types. Solution of feldspar in sedimentary rocks is common in some formations and contributes significantly to the porosity. Shenhav (1971) described small voids in feldspars in some Cretaceous sandstones in Israel but generally the role that the solution of feldspar may play in increasing reservoir porosity has not been stressed. The present writers have observed partially dissolved feldspar in the Mississippian Berea Sandstone and the Cambrian Mt. Simon Sandstone of West Virginia and Ohio. Pre-liminary study of the Devonian Benson sand o