Changes

Figure 4 illustrates the sequence of events associated with diagenetic trap formation. In the example shows the mechanism original trapping with reduced porosity updip as a result of changes facies of grainstone oolitic into calcareous mudstone.

Figure 4 illustrates the sequence of events associated with diagenetic trap formation. In the example shows the mechanism original trapping with reduced porosity updip as a result of changes facies of grainstone oolitic into calcareous mudstone.

[[File:UGM_Subsurface_Fig_4.png|thumb|300px|{{figure number|4}}]]

[[File:UGM_Subsurface_Fig_4.png|thumb|300px|{{figure number|4}}Establishment of diagenetic trap associated with the initial migration of oil.

(A) The accumulation of hydrocarbons in the stratigraphic trap as a result of loss updip porosity. Calcite cementation happened to overburden contact oil / water. (B) With folding contact of oil / water layer is at end position a reservoir that has no relation with the structure (Aquitaine, 1982)]]

At the contact of oil / water in the reservoir is often precipitate calcite cement extensively. This phenomenon generally occurs in some carbonate reservoir which showed no evidence of cementation except in contact area of oil / water. The calcite cement occurrences associated with the reaction of sulfate reducing bacteria which can be explained in the following reaction (Friedman and Sander, 1978).

At the contact of oil / water in the reservoir is often precipitate calcite cement extensively. This phenomenon generally occurs in some carbonate reservoir which showed no evidence of cementation except in contact area of oil / water. The calcite cement occurrences associated with the reaction of sulfate reducing bacteria which can be explained in the following reaction (Friedman and Sander, 1978).