Reservoirs Resulting from Facies-Independent Dolomitization: Case Histories from the Trenton and Black River Carbonate Rocks of the Great Lakes Area1
Brian D. Keith, 1988. "Reservoirs Resulting from Facies-Independent Dolomitization: Case Histories from the Trenton and Black River Carbonate Rocks of the Great Lakes Area", The Trenton Group (Upper Ordovician Series) of Eastern North America: Deposition, Diagenesis, and Petroleum, Brain D. Keith
Download citation file:
Reservoirs in the Upper Ordovician Trenton Limestone and the Black River Group in Indiana, Michigan, and Ohio form a major oil province, important since 1884. This province (America’s first giant oilfield) has yielded more than 600 MMBO. This includes the giant Albion-Scipio Trend (120 MMBO), discovered in 1956. Although production from the Trenton and Black River carbonates is high, little has been known about the nature and distribution of their reservoirs. Recent research indicates that they do not contain any depositional (primary) porosity. Reservoirs exist only where dolomitization or fracturing or a combination has occurred.
Trenton and Black River dolomitization does not conform to facies-related models, but must be related either to fluid movement along fractures associated with tectonic features or to burial dolomitization. A comparison of fields with dolomitization along linear fault (or fracture) zones and those showing regional burial dolomitization indicates the relative importance of faults and fractures. Oil recovery from fault/fracture-dolomite reservoirs is 2500 to 12, 000 bbl/acre, and that from burial-dolomite reservoirs is only 540 to 1000 bbl/acre.
Figures & Tables
The Trenton Group (Upper Ordovician Series) of Eastern North America: Deposition, Diagenesis, and Petroleum
Regional facies for the Upper Ordovician Series (global classification) of eastern North America consist of clean (pure) carbonates, mixed carbonates and terrigenous clastics, shale, terrigenous clastics coarser than shale, and terrigenous clastics prograding over carbonates. The last facies is characteristic of the Upper Ordovician. Maps and cross sections for stages of the Upper Ordovician demonstrate the influence of regional tectonic events on the sedimentation pattern of these facies.