Regional-scale porosity and permeability variations in Upper Devonian Leduc buildups: Implications for reservoir development and prediction in carbonates

Journal Article · Sat Oct 01 04:00:00 EDT 1994 · AAPG Bulletin

OSTI ID:44965

Amthor, J E ^[1]; Mountjoy, E W ^[2]; Machel, H G ^[3]

---

1. KSEPL, Rijswijk (Netherlands)
2. McGill Univ., Quebec (Canada)
3. Univ. of Alberta, Edmonton (Canada)

Upper Devonian carbonate rocks of the Rimbey-Meadowbrook reef trend in the subsurface of central Alberta are characterized by a wide range of porosity and permeability values. Dolostones show the highest values of absolute and average horizontal and vertical permeability. For all rock types, horizontal permeability averages tens of times to several hundred times the vertical permeability. If considered irrespective of burial depth, limestones and dolomitic limestones are more porous than dolostones. There is an overall decrease of porosity and permeability in Leduc Formation carbonates with increasing burial depth and thermal maturity along the reef trend. At relatively shallow burial depths (<2000 m), limestone and dolomitized buildups have comparable porosity values and distributions. Dolomitization has resulted mainly in redistribution of primary limestone porosity to secondary dolomite porosity types with a concomitant minor increase in permeability. At greater burial depths (>2000 m), dolostones are significantly more porous and permeable than limestones. The better porosity and permeability of dolostones relative to limestones at greater depths is of economic significance for exploration in Upper Devonian carbonates of the deep Alberta basin (and probably other carbonate areas), where reservoirs are mostly found in dolostones and where limestones have a low reservoir potential and pose a considerable exploration risk. The best reservoir potential in the Leduc Formation of the deep Alberta basin occurs in dolomitized buildups that were connected to a regional conduit system.

• OSTI ID: 44965
• Journal Information: AAPG Bulletin, Journal Name: AAPG Bulletin Journal Issue: 10 Vol. 78; ISSN 0149-1423; ISSN AABUD2
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
ALBERTA
CARBONATE ROCKS
DEVONIAN PERIOD
DIAGENESIS
DRILL CORES
NATURAL GAS DEPOSITS
PERMEABILITY
PETROLEUM DEPOSITS
PHOTOMICROGRAPHY
POROSITY
RESERVOIR ROCK
RESOURCE POTENTIAL
SEDIMENTARY BASINS