Carbonate lithofacies

1. Carbonate sedimentology/1
Dunham (1962)
Carbonate classification

2. Carbonate sedimentology/2
Folk (1962)
Carbonate classification

3. Carbonate sedimentology/3
• Interpretation techniques applied to clastic
reservoirs can also be applied to carbonate
depositional systems.
• Carbonates however, differ from clastics due to
the importance of biogenic processes and their
susceptibility to diagenetic modifications.
Carbonates versus clastics

4. Carbonate sedimentology/5
• All primary sedimentary structures recognised in
siliciclastic rocks can occur in carbonates
(e.g. cross-bedding in ooid shoals, slumps etc.)
• In addition there may be:
– Biogenic structures (reefs etc.)
– Diagenetic structures unique to carbonates
Sedimentary structures

5. Carbonate sedimentology/6
The ultimate goal

6. Carbonate sedimentology/7
Carbonate lithofacies – core calibration
Vertical well
Boundary between FMI facies FMI7 and FMI4. The
burrowed surface is clearly visible (arrowed) as are the
packstone-filled burrows below.
Burrowed contact (dashed line)
between FMIF7 and FMIF4. Burrows
(squares) are filled with packstone.
Possible hardground.
FMIF7
FMIF4
Static image Dynamic image Slabbed core

7. Carbonate sedimentology/8
Carbonate lithofacies
FMI image facies associations vs Ka
0.01
0.10
1.00
10.00
100.00
1000.00
0 1 2 3 4 5 6
FMI image facies association
Ka
(mD)
FMIA1
FMIA2
FMIA3
FMIA4
FMIA5

8. Carbonate sedimentology/9
Conductive fracture
Resistive fracture
Fractures in carbonates
Vertical well