Formation damage in sandstones caused by clay dispersion and migration by. Pdf the influence of clay mineralogy on formation damage in. In sandstone acidizing, chlorite clay mineral caused iron hydroxide precipitation inside the cores during treatment with mud acid. Authigenic illite in the sandstone reservoirs of taiyuan. Avoiding acidinduced formation damage in aux vases reservoir.
Pdf formation damage in oil and natural gas reservoirs. Illite can break down and migrates in the cores during the. The sandstone cores used in this study contain from 1 to 18 wt% illite swellable and migratable clay mineral. Formation damage is an undesirable operational and economic problem that can occur during the. Gkay and rex 1966 firstly studied the formation damage, and concluded that the migration of smectite, illite and kaolinite particles in formation. Bennion,1999 described formation damage as, the impairment of the invisible, by the inevitable and uncontrollable, resulting in an indeterminate reduction of the unquantifiable. The minerals discussed belong to the smectite, kaolinite, illite and chlorite groups respectively. Since the 1960s, experts had noticed that formation damage. Clay minerals damage quantification in sandstone rocks using core. It causes many problems starting from reduction of the well productivity till the whole failure of the well. Removing formation damage and stimulation of deep illiticsandstone. Formation damage assessment, control, and remediation. Controlling formation damage caused by kaolinite clay. Illite in shales is a mixture of detrital mica and its weathering products with diagenetic illite formed by reaction with pore fluids.
The san1les initially contained only kaolinite and illite clays, classically classified as nonwater sensitive. Removing formation damage and stimulation of deep illitic. Mobilization, migration, and deposition of fine particles internal or external 2. During petrophysical and petrographical analyses of the core plugs, generally, we pay close attention to the fines migration when we observe kaolinite minerals filling the pore space or lining the pores. The illite clay mineral and chlorite can cause the formation damage on hcl injection. Formation damage causing rockfluid interactions bennion and thomas, 1994 1. Formation damage overview professor dr abdel sattar dahab petroleum engineering department cairo university 1 the. Glda was found to be highly effective in creating wormholes over a wide range of ph 1. Illite can break down and migrates in the cores during the acid injection. Formation damage free download as powerpoint presentation. Formation damage is a serious problem in oil and gas industry. Effects of clay mineral and physicochemical variables. Pdf the influence of individual clay minerals on formation damage of reservoir. Increasing temperature enhanced the reaction rate, more calcite was.
Illite content of 1, 10, 14, and 18 wt% of the sandstone cores were used in the. The minerals discussed belong to the smectite, kaolinite, illite and chlorite. The influence of individual clay minerals on formation. The conditions leading to a drastic reduction of permeability formation damage, at low temperature, by kaolinite have been documented in the literature. Evaluation of formation damage and assessment of well. Pdf the influence of individual clay minerals on formation. Abstract illiticsandstone reservoirs are very sensitive to hclbased fluids. Alteration of porous media and particle surface absorption, adsorption, wettability change, and swelling. Illite also may precipitate in the pores of sandstone reservoirs, impeding fluid flow. Investigation of formation damage from mud cleanout acids. Clay minerals damage quantification in sandstone rocks. The influence of clay mineralogy on formation damage in north sea. Evidence against a separate early phase of illite formation in porelining mode includes kar dating showing that the age of north sea illites is always much.