San Andres Formation: Outcrop to Subsurface Stratigraphic Framework

1
San Andres FormationOutcrop to Subsurface
Stratigraphic Framework
Charlie Kerans Department of Geological
Sciences John A. and Katherine G. Jackson School
of Geosciences The University of Texas at Austin
2
Acknowledgements

• Jerry Lucia, mentor
• Colleagues on San Andres Tinker, Ruppel,
  Gardner, Fitchen, Nance
• WTGS/PBS-SEPM/Midland Geological Community - Al
  Smith, Bob Ward, Bob Trentham, Emily Stoudt,
  University Lands Group

3
Outline

• Develop Outcrop Model
• Discuss Current San Andres Plays
• Propose more stratigraphically based play model
  for San Andres Fields using outcrop model
• Illustrate examples from Vacuum, Slaughter,
  Wasson, Seminole, Hobbs, and Midland Farms fields
• Propose representative heterogeneity styles for
  San Andres stratigraphically-based plays

4
Outcrop to Subsurface Google It!
Northwest Shelf
Delaware Basin
Capitan G28 Margin
San Andres G9 Margin
LCC
5
Outcrop Model
Rio Hondo
Rio Penasco
Algerita Escarpment
Brokeoff Mts, LCC
Western Escarp.
Anhydrite and anhydritic dolostone
Restricted marine peloidal wk-pk and peritidal
High-energy ramp-crest grainstones
Outer ramp fusulinid-dominated facies
Open marine limestones and dolostones, L7-8
Deeper-water mudstones (Cutoff)
6
Permian Basin Plays,Dutton et al (2005)
7
Stratigraphic Terminology
Modified after Kerans, 2000, Trentram and Smith,
2002
8
Hierarchy of Composite/High-Frequency Sequences
for Late Leonardian-Guadalupian
9
Classification of San Andres Reservoirs on basis
of StratigraphicSetting
1
1
2
3
2
4
1b
5
3

• L7-8-G1-2 interc. dolo-evap
• 1b. L7-L8, G1? Open shelf and buildups
• 2. Cyclic G1-4
• 3. Stacked G8-9 and Gbg G10
• 4. Karst-modified, anhydrite-free G8-9
• 5. Oolitic Grayburg lowstand G10

4
10
San Andres Reservoir Settings
Vacuum, Gbg-Jk Maljamaar
Wasson, Seminole, Goldsmith
Yates, Hobbs
3
2
4
Mabee, Mid. Fms
Brahaney
5
Slaughter
1
Levelland
1b
Howard-Glasscock, Holt, SA Deep
Anhydrite and anhydritic dolostone
Restricted marine peloidal wk-pk and peritidal
High-energy ramp-crest grainstones
Outer ramp fusulinid-dominated facies
Open marine limestones and dolostones, L7-8
Deeper-water mudstones (Cutoff)
11
San Andres Play Types
Field Type Strat Setting Structural Control Scale of Key Heterogeneities Examples
1 TSS, early HSS Platform Interior CS9 L7-L8, G1-G3 (TSS-eHSS) Pure strat trap HFS-scale interc of TST carbs and HST? Evaps. Slaughter, Levelland, Chavaroo
1b TSS, early HSS outer shelf and buildups L7, L8 Structural drape and buildup topography Dolo-ls and HFC stacking plus local buildup topography Howard-Glasscock, Iatan, Holt, SA Deep
2 Mid-platform CS9 G2-4, CS9 HSS Comb. differental compact., drape of deep struct. HFC-scale heterogeneities Wasson, Seminole, Goldsmith
3 Stacked CS10, CS11 G8-9, CS10 TSS-HSS and CS11 TSS Comb. Drape over CS8 (Glorieta) and CS9 margin (LSA) margins Amalgamated grain-rich HFC with sulfate-cemented karst overprint
12
San Andres Play Types byStratigraphic Setting
Field Type Strat. Setting Structural Control Scale of Key Heterogeneities Examples
4 Stacked CS10 HFS and Karst overprint CS10 TSS-HSS (G8-9) Drape over major deep structures, Proximity to Capitan aquifer and sulfate removal! Karst porosity plus open, high-flow matrix zones from sulfate leaching Yates, Hobbs
5 CS11 Lowstand (Grayburg) CS 11 (G11) Structural drape and strat. trap HFC layering plus unique oomoldic zones Maybee, Midland Fms.
13
Classification of San Andres Reservoirs on basis
of StratigraphicSetting
1
1
2
3
2
4
1b
5
3

• L7-8-G1-2 interc. dolo-evap
• 1b. L7-L8, G1? Open shelf and buildups
• 2. Cyclic G1-4
• 3. Stacked G8-9 and Gbg G10
• 4. Karst-modified, anhydrite-free G8-9
• 5. Oolitic Grayburg lowstand

4
14
Location of Profiles
Slaughter
Wasson
Vacuum
Seminole
Hobbs
Cowden-M.F.
outcrop
15
West to East Margin/ProgradationPatterns
Ancestral Rockies Pattern?
16
Permian Basin Setting withinAncestral Rocky Mt.
SW-NE Compression
Ye et al. (19960
17
Wolfcamp-Leonardian-GuadalupianOutcrop Model and
Position of ShelfMargins
G4
G9
L7,8
L3
L6
L1
18
Leonardian-Guadalupian Margins,Outcrop Profile
Western Escarpment
19
Leonardian-Guadalupian Margins,Outcrop Profile
Cutoff Ridge
Top G9
Top G8
20
Location of Profiles SlaughterType 1
Slaughter
Wasson
Vacuum
Seminole
Hobbs
Cowden-M.F.
outcrop
21
San Andres Reservoir Settings
Vacuum, Gbg-Jk Maljamaar
Wasson, Seminole, Goldsmith
Yates, Hobbs
3
2
4
Mabee, Mid. Fms
Brahaney
5
Slaughter
1
Levelland
1b
Howard-Glasscock, Holt, SA Deep
Anhydrite and anhydritic dolostone
Restricted marine peloidal wk-pk and peritidal
High-energy ramp-crest grainstones
Outer ramp fusulinid-dominated facies
Open marine limestones and dolostones, L7-8
Deeper-water mudstones (Cutoff)
22
Dip Log Line near Vacuum
Silver And Todd (1969)
23
Vacuum Dip Seismic Profile showingStacked CS8
and CS9 margins
Pranter et al. (2004)
24
Facies/Cycle StackingCS9 Upper San Andres
Composite Seq.
G9 HFS, CS10 HSS
G8 HFS, CS10 TSS
25
Location of Profiles SlaughterType 1
Slaughter
Wasson
Vacuum
Seminole
Hobbs
Cowden-M.F.
outcrop
26
Reservoir Style and StratigraphicSetting Note
Difference in Shelf Margins
1
2
3
2
4
3
1b
5
3
2
27
San Andres Reservoir Settings
Vacuum, Gbg-Jk Maljamaar
Wasson, Seminole, Goldsmith
Yates, Hobbs
3
2
4
Mabee, Mid. Fms
Brahaney
5
Slaughter
1
Levelland
1b
Howard-Glasscock, Holt, SA Deep
Anhydrite and anhydritic dolostone
Restricted marine peloidal wk-pk and peritidal
High-energy ramp-crest grainstones
Outer ramp fusulinid-dominated facies
Open marine limestones and dolostones, L7-8
Deeper-water mudstones (Cutoff)
28
Slaughter-Levelland TrendL7, L8, G1, G2?
29
Slaughter-Levelland TrendL7, L8, G1, G2?
G9
G4, G8
G3
G2
G1
L8
30
Location of Profiles Wasson/Seminole - Type 2
Slaughter
Wasson
Vacuum
Seminole
Hobbs
Cowden-M.F.
outcrop
31
Reservoir Style and StratigraphicSetting
1
2
3
2
3
32
San Andres Reservoir Settings
Vacuum, Gbg-Jk Maljamaar
Wasson, Seminole, Goldsmith
Yates, Hobbs
3
2
4
Mabee, Mid. Fms
Brahaney
5
Slaughter
1
Levelland
1b
Howard-Glasscock, Holt, SA Deep
Anhydrite and anhydritic dolostone
Restricted marine peloidal wk-pk and peritidal
High-energy ramp-crest grainstones
Outer ramp fusulinid-dominated facies
Open marine limestones and dolostones, L7-8
Deeper-water mudstones (Cutoff)
33
Wasson San Andres Setting
WNW
ESE
Wasson
34
Wasson Original Layering
35
Wasson Porosity Zones
36
Location of Profiles Wasson/Seminole - Type 2
Slaughter
Wasson
Vacuum
Seminole
Hobbs
Cowden-M.F.
outcrop
37
(No Transcript)
38
SSAU Core Example HFC Structure
39
San Andres Fields, Permian BasinPaleogeography
of Ward et al (1986)
Modified from Ward et al (1985) by Scholle 2005
40
Location of Profiles Wasson/Seminole - Type 2
Slaughter
Wasson
Vacuum
Seminole
Hobbs
Cowden-M.F.
outcrop
41
San Andres Reservoir Settings
Vacuum, Gbg-Jk Maljamaar
Wasson, Seminole, Goldsmith
Yates, Hobbs
3
2
4
Mabee, Mid. Fms
Brahaney
5
Slaughter
1
Levelland
1b
Howard-Glasscock, Holt, SA Deep
Anhydrite and anhydritic dolostone
Restricted marine peloidal wk-pk and peritidal
High-energy ramp-crest grainstones
Outer ramp fusulinid-dominated facies
Open marine limestones and dolostones, L7-8
Deeper-water mudstones (Cutoff)
42
3D Seismic Volume - Hobbs

• Hobbs paleostructure influences
• San Andres margin position
• Paleostructure assumed responsible for
• Enhanced top-SA karst

NW
SE
43
San Andres-Grayburg ContactCutoff Ridge,
Guadalupe Mountains
Upper Gbg
Lower Gbg
U. San Andres G9
Top G8
44
San Andres-Grayburg ContactCutoff Ridge,
Guadalupe Mountains
NHU 29-132
Upper Gbg
Lower Gbg
U. San Andres G9
Top G8
45
NW-SE Line Thru 24-424
46
NS Line showing LSA and USAArchitecture
47
Hobbs Field, CS9 TSS (G8HFS)
3Ea
3H?
3F
3G
48
Hobbs Field CS9 HSS (G9 HFS)
1A
1B
2C
2D
3E
49
Upper San Andres Karst Development Top G8 and G9
50
Confined vs. Diffuse Karst Model
Confined Karst Model
Diffuse Karst Model
Modified from Meyers (1988)
51
Cave-Fill Breccia and Siltstone33-232
52
Hydrology of Diffuse Flow KarstHobbs Upper San
Andres Guad 9_2 HFS
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Anhydrite DissolutionPossibly Late, Post-burial
54
San Andres Play Types byStratigraphic Setting
Field Type Strat. Setting Structural Control Scale of Key Heterogeneities Examples
4 Stacked CS10 HFS and Karst overprint CS10 TSS-HSS (G8-9) Drape over major deep structures, Proximity to Capitan aquifer and sulfate removal! Karst porosity plus open, high-flow matrix zones from sulfate leaching Yates, Hobbs
5 CS11 Lowstand (Grayburg) CS 11 (G11) Structural drape and strat. trap HFC layering plus unique oomoldic zones Maybee, Midland Fms.
55
San Andres Reservoir Settings
Vacuum, Gbg-Jk Maljamaar
Wasson, Seminole, Goldsmith
Yates, Hobbs
3
2
4
Mabee, Mid. Fms
Brahaney
5
Slaughter
1
Levelland
1b
Howard-Glasscock, Holt, SA Deep
Anhydrite and anhydritic dolostone
Restricted marine peloidal wk-pk and peritidal
High-energy ramp-crest grainstones
Outer ramp fusulinid-dominated facies
Open marine limestones and dolostones, L7-8
Deeper-water mudstones (Cutoff)
56
Location of Profiles Wasson/Seminole - Type 2
Slaughter
Wasson
Vacuum
Seminole
Hobbs
Cowden-M.F.
outcrop
57
Lowstand Setting of Midland Fms.,Mabee Fields,
CS11 LSS
CS10
CS9
CS11 LSS G10 HFS Mid. Fms
CS5-8 L1-6
Cherry Cnyn?
Brushy Cnyn?
58
Stratigraphic Terminology
Modified after Kerans, 2000, Trentram and Smith,
2002
59
Outcrop to Subsurface Google It!
Northwest Shelf
Delaware Basin
Capitan G28 Margin
San Andres G9 Margin
LCC
60
San Andres Reservoir Settings
Vacuum, Gbg-Jk Maljamaar
Wasson, Seminole, Goldsmith
Yates, Hobbs
3
2
4
Mabee, Mid. Fms
Brahaney
5
Slaughter
1
Levelland
1b
Howard-Glasscock, Holt, SA Deep
Anhydrite and anhydritic dolostone
Restricted marine peloidal wk-pk and peritidal
High-energy ramp-crest grainstones
Outer ramp fusulinid-dominated facies
Open marine limestones and dolostones, L7-8
Deeper-water mudstones (Cutoff)
61
San Andres Play Types
Field Type Strat Setting Structural Control Scale of Key Heterogeneities Examples
1 TSS, early HSS Platform Interior CS9 L7-L8, G1-G3 (TSS-eHSS) Pure strat trap HFS-scale interc of TST carbs and HST? Evaps. Slaughter, Levelland, Chavaroo
1b TSS, early HSS outer shelf and buildups L7, L8 Structural drape and buildup topography Dolo-ls and HFC stacking plus local buildup topography Howard-Glasscock, Iatan, Holt, SA Deep
2 Mid-platform CS9 G2-4, CS9 HSS Comb. differental compact., drape of deep struct. HFC-scale heterogeneities Wasson, Seminole, Goldsmith
3 Stacked CS10, CS11 G8-9, CS10 TSS-HSS and CS11 TSS Comb. Drape over CS8 (Glorieta) and CS9 margin (LSA) margins Amalgamated grain-rich HFC with sulfate-cemented karst overprint
62
San Andres Play Types byStratigraphic Setting
Field Type Strat. Setting Structural Control Scale of Key Heterogeneities Examples
4 Stacked CS10 HFS and Karst overprint CS10 TSS-HSS (G8-9) Drape over major deep structures, Proximity to Capitan aquifer and sulfate removal! Karst porosity plus open, high-flow matrix zones from sulfate leaching Yates, Hobbs
5 CS11 Lowstand (Grayburg) CS 11 (G11) Structural drape and strat. trap HFC layering plus unique oomoldic zones Maybee, Midland Fms.
63
Conclusions

• Outcrop model proposed emphasizing stratigraphic
  diachroneity
• 5 main stratigraphic settings of San Andres
  Fields
• Using insights from outcrop, field studies, and
  seismic, possible to classify most of existing
  San Andres fields into these 5 styles
• Need a better set of San Andres maps for plotting
  San Andres plays, not a Leonardian margin map