Deep Gas Reservoir Play, Central
and Eastern Gulf
Summary
 Introduction
 Petroleum
System Analysis
 Resource Assessment
 Exploration Strategy
Introduction
Gulf Coast Interior Salt Basins
Gulf Coast Interior Salt
Basins
Stratigraphy
Petroleum System Analysis
Petroleum Source Rocks
 Upper
Jurassic Smackover lime mudstone
beds served as an effective regional
petroleum source rock
 Upper Cretaceous Tuscaloosa Marine
shale beds served as a local source rock
 Upper most Jurassic and Lower
Cretaceous beds were possible source
rocks
Burial History
North Louisiana
Salt Basin
K’
Cross Sections
Location
N
North Louisiana Salt Basin
Cross Section
S
VE: 32X
Burial History Profile
North Louisiana Salt Basin
API: 1706920079
- Sediment accumulation
rates were greatest in the
Jurassic (196-264 ft/my)
- 50-60% of the tectonic
subsidence occurred in the
Late Jurassic (135-157 ft/my)
North Louisiana Salt Basin,
Sabine Uplift Cross Section
N
S
VE: 22X
Burial History Profile NLSB, Sabine Uplift
North Louisiana Salt Basin,
Monroe Uplift Cross Section
N
S
VE: 30X
North Louisiana Salt Basin Cross Section
W
E
VE: 22X
Burial History Profile NLSB, Monroe Uplift
Mississippi Interior Salt Basin
Cross Section Location
Mississippi Interior Salt Basin
Cross Section
N
S
VE: 16X
Burial History Profile
Mississippi Interior Salt Basin
Thermal Maturation and Expulsion
History
North Louisiana Salt Basin
Cross Section Location
K’
Model Calibration
Thermal Maturation History Profile
North Louisiana Salt Basin
Thermal Maturation Profile Cross Section
North Louisiana Salt Basin
Average Maturation Depth
6,500ft
12,000ft
Hydrocarbon Expulsion Profile
North Louisiana Salt Basin
Peak Oil
Peak Gas
Thermal Maturation History Profile NLSB,
Sabine Uplift
Hydrocarbon Expulsion Plot NLSB,
Sabine Uplift
Thermal Maturation History Profile NLSB,
Monroe Uplift
Hydrocarbon Expulsion Plot NLSB,
Monroe Uplift
Mississippi Interior Salt Basin
Cross Section Location
Thermal Maturation History Profile
Mississippi Interior Salt Basin
Thermal Maturation Profile Cross Section
Mississippi Interior Salt Basin
Average Maturation Depth
8,000ft
16,000ft
Hydrocarbon Expulsion Plot
Mississippi Interior Salt Basin
Peak Oil
Peak Gas
Comparison of NLSB and MISB
Modified from Mancini et al. (2006a)
Event Chart for Smackover Petroleum
System in the North Louisiana and
Mississippi Interior Salt Basins
Geologic Model
SSW-NNE Section (B-B’)
Oil Migration
SW-NE Section (B-B’)
Gas Migration
SW-NE Section (B-B’)
Gas Migration at 99 Ma
SW-NE Section (B-B’)
Geologic Model
NW-SE Section
Gas Migration Profile
NW-SE Section
Gas Migration at 99 Ma
NW-SE Section
Geologic Model
N-S Section
Oil Migration
N-S Section
Gas Migration at 99 Ma
N-S Section
Geologic Model
N-S Section (Monroe Uplift)
Oil Migration
N-S Section (Monroe Uplift)
Gas Migration at 52 Ma
N-S Section (Monroe Uplift)
Resource Assessment
Production Data
Production Data
Methodology for Resource
Assessment
Schmoker (1994)

The mass of hydrocarbons generated from a petroleum source
rock can be calculated by using the following equations:
1. (TOC wt%100)(FD)(VU) = MOG
2. HI Original – HI Present = HG
3. (MOG) (HG) (10-6kg/mg) = HCG
Where: TOC = total organic carbon
FD = formation density
VU = volume of unit
MOG = mass of organic carbon
HI = hydrogen index
HG = hydrocarbons generated per gram of organic carbon
HCG = hydrocarbon generated by source rock unit
Key Parameters
Basin Parameters
NLSB Platte River Software —
Gas Generated
TOC = 1.0%
Type II kerogen
Transient heat flow
6,400 TCF
By P. Li
NLSB Platte River Software —
Gas Expelled
TOC = 1.0%
Type II kerogen
1,280 TCF
By P. Li
MISB Platte River Software —
Gas Generated
TOC = 1.5%
Type II kerogen
Transient heat flow
3,130 TCF
By P. Li
MISB Platte River Software —
Gas Expelled
TOC = 1.5%
Type II kerogen
Transient heat flow
843 TCF
Saturation threshold = 0.1
By P. Li
Comparison of Hydrocarbon
Generation & Expulsion Volumes
Method
North Louisiana Salt Basin
Mississippi Interior Salt Basin
Generation
Schmoker (1994)
Generation
hydrocarbon (bbls)
2,870×10
Oil (bbls)
832×109
Gas (TCF)
9
14,177
Generation
hydrocarbon (bbls)
Platte River Software
Gas (TCF)
9
1,715×109
6,400
Expulsion
Saturation Threshold
Gas (TCF)
Oil (bbls)
580×109
Gas (TCF)
4,050
hydrocarbon (bbls)
1,540×109
Oil (bbls)
1,090×109
Gas (TCF)
3,130
Expulsion
0.1
Oil (bbls)
910×109
Generation
2,640×10
Oil (bbls)
hydrocarbon (bbls)
Saturation Threshold
9
970×10
1,280
Oil (bbls)
Gas (TCF)
0.1
442×109
843
Modified from Mancini et al. (2006b)
Gas Resource
Potential Secondary Gas Resource
Basin
Gas Generated (TCF)*
Gas Potentially Available (TCF)**
Gas Produced (TCF)
NLSB
4,800
48 to 240
29
MISB
2,350
23.5 to 115.5
13
*Assuming that 75% of total gas calculated with the Platte River Software Approach is from late cracking of oil
in the source rock.
**Assuming a 1 to 5% efficiency in expulsion, migration and trapping processes.
Exploration Strategy
NLSB Thermal Maturation
% Ro
0 .0
0
5 ,0 0 0
7,000
1 0 ,0 0 0
D E P T H (feet)
12,000
1 5 ,0 0 0
2 0 ,0 0 0
2 5 ,0 0 0
3 0 ,0 0 0
3 5 ,0 0 0
0.55
1 .0
1.3
2 .0
3 .0
4 .0
MISB Thermal Maturation
% Ro
0.0
0
5,000
10,000
11,000
DEPTH (feet)
15,000
16,500
20,000
25,000
30,000
35,000
40,000
1.0
0.55
1.3
2.0
3.0
4.0
Manila-Conecuh Thermal Maturation
Reservoir Characteristics
Deep Gas Reservoir Areal Distribution
Conclusions
 In
the North Louisiana Salt Basin, Upper
Jurassic and Lower Cretaceous
Smackover, Cotton Valley, Hosston, and
Sligo have high potential to be deeply
buried gas reservoirs (>12,000 ft).
 In the Mississippi Interior Salt Basin,
Upper Jurassic and Lower Cretaceous
Norphlet, Smackover, Haynesville, Cotton
Valley, Hosston, and Sligo have high
potential to be deeply buried gas
reservoirs (>16,500 ft).