Tag Query Results

Marine diagenesis embraces all processes that take place on the sea floor after sedimentation and before burial. It includes bioturbation, boring and micritisation, cementation, dolomitization and, less commonly, dissolution

Dolomitization is the diagenetic process by which limestone is converted to dolostone. A large proportion of the World's oil and gas reserves are in dolomitized or partially dolomitized reservoirs. Dolomitization can signifcantly improve reservoir properties, but this is not always the case and therefore it is important to determine the timing and processes governing dolomitization to assess reservoir quality

Dolomitization of limestone to form dolostone by geothermal convection of seawater can occur locally, usually on the platform margin or in the vicinity of faults.

Dolomitization of limestone by reflux can form dolostone over extensive areas of a platform (10’s to 100’s kilometres). The process usually results in a wholesale replacement of the limestone by a crystalline dolomite, which may be fabric-retentive or fabric destructive, with a complete reorganisation of porosity.

Since dolomite cementation and replacement is kinetically favoured by higher temperatures, then dolomitisation should be more favourable under burial conditions than in the near-surface environment. Typically, dolomitization in the burial realm forms non-stratabound bodies, usually around faults, with complex textures and pore networks.