AQUEOUS GELLABLE COMPOSITION, USEFUL FOR MODIFYING THE PERMEABILITY OF A PETROLEUM RESERVOIR

摘要

An aqueous gellable composition having a delayed gelling time is disclosed, which contains a water-soluble polymer crosslinkable with Cr3+ and a crosslinking and gel- retarding system containing a Cr3+ ion and a salicylic acid ligand, wherein said ligand can be in free form, or in the form of a complex with Cr3+, or partially in free form and partially in complexed from. Such a composition is useful for modifying the permeability in petroleum reservoirs, within a wide range of temperatures, of from about 60.degree.C to 120.degree.C, or higher temperatures.