Changes

Subsurface diagenetic process which produces or increases the porosity is dissolution and secondary porosity occurence. Rock dissolution in water saturated condition produces mold, vein, hole, and channel with or without the breakdown of this appearance (associated with cave and karst generally) and the solution which increases the interparticle porosity. This porosity type divides the origin generally and distinguishes the level based on the type. Generally, the origin shows the similar geological setting, where the porosity builds up and helps geologist to eliminate the unsuitable setting with dissolution. Geological setting where dissolution normally occurs is in the phreatic-meteoric zone, mixing zone, and vadose zone. Dissolution also may occur in the subsurface zone with rocks and water at the outside of chemical equilibrium.

Subsurface diagenetic process which produces or increases the porosity is dissolution and secondary porosity occurence. Rock dissolution in water saturated condition produces mold, vein, hole, and channel with or without the breakdown of this appearance (associated with cave and karst generally) and the solution which increases the interparticle porosity. This porosity type divides the origin generally and distinguishes the level based on the type. Generally, the origin shows the similar geological setting, where the porosity builds up and helps geologist to eliminate the unsuitable setting with dissolution. Geological setting where dissolution normally occurs is in the phreatic-meteoric zone, mixing zone, and vadose zone. Dissolution also may occur in the subsurface zone with rocks and water at the outside of chemical equilibrium.

The interaction between water and rocks where saturated fluide occurs, is causing a stable reaction which changing metastable carbonate or the other stable reaction (recrystallization, includes neomorphism). Weathering and soil formation process in the unconformity involves a combination of diagenetic process that is dissolution, precipitation, biological activity, and neomorphism. Soil and low weathering zone are not always important as the reservoir rocks, because the porosity size of matrix in carbonate is relatively small and have high capillary pressure.

The interaction between water and rocks where saturated fluide occurs, is causing a stable reaction which changing metastable carbonate or the other stable reaction (recrystallization, includes neomorphism). Weathering and soil formation process in the unconformity involves a combination of diagenetic process that is dissolution, precipitation, biological activity, and neomorphism. Soil and low weathering zone are not always important as the reservoir rocks, because the porosity size of matrix in carbonate is relatively small and have high [[capillary pressure]].

General dissolution plays a role as corrosion and increasing porosity in lower burial setting. Lower burial dissolution is called mesogenesis dissolution, following Choquette and Pray<ref name=CP1970> Choquette, P. W. and L. C. Pray, 1970, [http://archives.datapages.com/data/bulletns/1968-70/data/pg/0054/0002/0200/0207.htm Geologic nomenclature and classification of porosity in sedimentary carbonates]: AAPG Bulletin, vol. 54, pp. 200-207</ref> terminology, carbonate porosity classification (Mazullo and Harris, 1992). Saturation depends on CaCO3 in the fluide of burial because the fluide can be rich of CO2, H2S or organically acid. Burial dissolution makes the lower burial-carbonate reservoir to have porosity and permeability which can produce hydrocarbon, though standard “dogma” said that burial carbonate has 5% or low porosity. Increasing of porosity by the diagenetic dissolution produces size of pore with shape with that’s interconnected level widely.

General dissolution plays a role as corrosion and increasing porosity in lower burial setting. Lower burial dissolution is called mesogenesis dissolution, following Choquette and Pray<ref name=CP1970> Choquette, P. W. and L. C. Pray, 1970, [http://archives.datapages.com/data/bulletns/1968-70/data/pg/0054/0002/0200/0207.htm Geologic nomenclature and classification of porosity in sedimentary carbonates]: AAPG Bulletin, vol. 54, pp. 200-207</ref> terminology, carbonate porosity classification (Mazullo and Harris, 1992). Saturation depends on CaCO3 in the fluide of burial because the fluide can be rich of CO2, H2S or organically acid. Burial dissolution makes the lower burial-carbonate reservoir to have porosity and permeability which can produce hydrocarbon, though standard “dogma” said that burial carbonate has 5% or low porosity. Increasing of porosity by the diagenetic dissolution produces size of pore with shape with that’s interconnected level widely.