RhoVeTM MethodA New Empirical Pore Pressure Transform

GCS Solutions, Inc. geopressure consulting services & solutions

This presentation and all intellectual property discussed in this presentation are the property of GCS Solutions, Inc. and/or Matt Czerniak. GCS Solutions, Inc. is also currently working towards a development agreement with DynaView.

RhoVe method –

Offers an interactive approach to pore pressure estimation that is both intuitive and robust…

”I think it is valuable as a team to see what different pore pressure estimation approaches yield, and then to be able to weigh the merits in which it may or may not be plausible for our exact usage” – (Anadarko Geoscientist).

0.0

0.1

0.2

DTCO Sonic

Rhob Density

0.3

DTCO Sonic

Rhob Density

0.4

0.5

0.6

0.7

0.8

Modified from Swarbrick et al TLE 2012

The active pore pressure estimation follows the standard pore pressure protocol workflow using Terzaghi’s (1996) relationship:

σv‘ = Sv – PPwhere PP is the pore pressure, Sv is the Total Vertical Stress (overburden) and, σv‘ is the Vertical Effective

Stress.

Joint Industry Project - DEA 119

An Improved Methodology to Predict Predrill Pore Pressure in Deepwater Gulf of Mexico - KSI

The goal of this project was to develop an improved methodology for pre-drill pore pressure prediction in deep water wells. The project began in early 1999 and the first phase was completed in April 2001. The project centered around the collection of data for more than 100 wells in the deep water Gulf of Mexico and the utilization of that data to develop and test new and improved models and methods.

Modified after Katahara, 2003 OTC

Mechanical vs. Chemical

Arrhenius Law

ki = Ai e-Ei RT

Describes the controls of temperature and time on the rate and extent of chemical reaction (Roaldset et al., 1998).

**note: subscript i denotes a parallel reaction

after Dutta, 2002 TLE

Dutta 2002 TLE

Shallow

Deep

AllSmectite

AllIllite

after Dutta, 2002 TLE

Dutta 2002 TLE

Shallow

Deep

AllSmectite

AllIllite

Smectite-Illite Conversion

Pollastro, C&CM 1993

Freed & Peacor, CM 1989

Bethke & Altaner, C&CM 1986

after Alberty, SPE DL Series, 2011

Alberty-McLean, OTC 2003

ILLITE

SMECTITE

Alberty

interlayer

Illite:K2 Al4 (Si6 Al2) O20 (OH)4Montmorillonite (Smectite): Al2 Si4 O10 (OH)2 n H2O

https://www.ihrdc.com/els/ipims-demo/t26/offline_IPIMS_s23560/resources/data/G4105.htm

Illite:K2 Al4 (Si6 Al2) O20 (OH)4Montmorillonite (Smectite): Al2 Si4 O10 (OH)2 n H2O

https://www.ihrdc.com/els/ipims-demo/t26/offline_IPIMS_s23560/resources/data/G4105.htm

Rho-V-e MethodMars Rover “Opportunity”

RhoVeTM Method(U.S. patent pending - copyright © 2016)

Summary Interactive (and fast) - Premised on a continuum of “virtual”, normally pressured

synthetic rock properties models Pore pressure is calculated by directly applying RhoVe-derived Velocity & Density-

Effective Stress trends Subsalt Applications – provides an alternative to Eaton Method, although Bowers

Method also still presents a viable solution Handles varying shale lithologies with multiple NCTs, such as DWGoM Paleogene

(WCX-equivalent) & Offshore Canada (Nova Scotia) Two-parameter approach: a-term & alpha (α); includes the effects of clay diagenesis

and other factors, which are captured and utilized empirically for pore pressure analysis and prediction

Rationale for subdivision of major flow units (based on physical rock properties), which can be utilized in layer-based basin modeling applications

Consistent with Bower’s Method solutions for DWGoM fine-grained clastics.

1.00.1.00.

mudstone

γ = 2.0

1.0

0.

1.00. 1.00.

1.0

0.

1.00. 1.00.

claystone

γ = 2.2

% S:M denotes weight % of mixed-layer clay

% S:B denotes weight % of bulk rock

Dutta 67% S:M (9200’)Dutta 85% S:M

(3200’)

Dutta 21% S:M (14,400’)

Dutta 60% S:M (10,200’)

Dutta 32% S:M (12,100’)

XRD data from Casey, et al., 2015

RBBC< 0.2% S:B

7% I:B16% Clay:B

5-10% S:M

11% I:B38% Clay:B

85% S:MRask (9511’)

33% S:B

57% Clay:B42% I:B

45% S:MRask (13541’)

8% S:B14% I:B37% Clay:B

70% S:MRask (11168’)

20% S:B

33% S:B11% I:B54% Clay:B

RGOM-EI70-80% S:M

Dutta 30% S:M (11,000’)

Dutta 75% S:M (7500’)

Bowers GOM “slow” trendRhoVE-S

RhoVE-Ɛ

Telodiagenesis

Eodiagenesis Bowers GOM “slow” trend

Bowers GOM “slow” trend

after Sargent et al., 2015

(eodiagenesis)

(telodiagenesis)

BOWERS GOM “Slow” Trend RhoVE-ε RhoVE-S

Vo: 4790 4800 4900A: 2953 2000 4500B: 3.57 4.2 3

ρo: 1.3 1.3 1.3

V-Rho equation (Bowers, OTC 2001) :

V = V0 + A (ρ - ρo) B

RhoVE interm: a * (RhoVE-ε – RhoVE-S) + RhoVE-S

a = γα – αγDWGoM γ = 2.0 Offshore Nova Scotia γ = 2.2

mudstone

γ = 2.0

RhoVE-Ɛ

RhoVE-S

RhoVE-I

BOWERS GOM “Slow” Trend RhoVE-ε RhoVE-S

Vo: 4790 4800 4900A: 2953 2000 4500B: 3.57 4.2 3

ρo: 1.3 1.3 1.3

V-Rho equation (Bowers, OTC 2001) :

V = V0 + A (ρ - ρo) B

RhoVE interm: a * (RhoVE-ε – RhoVE-S) + RhoVE-S

a = γα – αγDWGoM γ = 2.0 Offshore Nova Scotia γ = 2.2

claystone

RhoVE-Ɛ

RhoVE-S

RhoVE-I

γ = 2.2

0.19

0.36

0.51

0.64

0.60

0.0

0.60

0.1

0.60

0.2

0.60

0.3

0.60

0.37

0.60

Bowers GOM “slow” trend

Bowers DW GoM (Default)

0.37

0.4

0.60

0.5

0.60

0.6

0.60

0.7

0.60

0.8

0.60

0.9

0.60

1.0

0.60

GoM calibrationwells converge onupper limit of a =0.6 No unique

Solution for α

a calculated from αDWGoM a-α relationship

GoM calibrationwells converge onupper limit of a =0.6 No unique

Solution for α

a calculated from αDWGoM a-α relationship

GoM calibrationwells converge onupper limit of a =0.6 No unique

Solution for α

a calculated from αDWGoM a-α relationship

Examples

• Lithology Discrimination: KC292-1BP2 Kaskida

• GOM Shelf: SMI23-5• Offshore Nova Scotia: H-23• DW GOM: PI526-1 Jack Hays• DW GOM Subsalt: KC292-1BP2 Kaskida

Examples

Smectite Dominated

Illiite Dominated

Illitic

Smectitic

Illitic

Smectitic

SMI23-005(H) Gulf of Mexico,

U.S.A.

Examples from GoM

Smectite Dominated

Illitic

Smectitic

Examples from GoM

Smectite Dominated

Illitic

Smectitic

Examples from GoM

Smectite Dominated

unloading

0.0

a = 0.51

0.03

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

unloading

unloadingunloading

1.6

Bowers Method (1994,2001)

corrected

corrected

corrected

2.2

Vmaxcorrected

Uncorrected

γ= 2.0

Corrected

Vmax

Bowers - 1995 SPE; 2001 OTC

H-23 Newburn Offshore Nova Scotia,

CANADA

Examples

Illiite Dominated

Illitic

Smectitic

0.0

a = 0.75

0.1

0.2

0.3

0.4

0.5

0.5

0.6

0.7

0.7

γ= 2.2

0.99

PI526-1 Jack Hays DW Gulf of Mexico,

U.S.A.

Bowers DW GoM (Default)

0.0

a = 0.51

Bowers DW GoM (Default)

0.1

Bowers DW GoM (Default)

0.2

Bowers DW GoM (Default)

0.3

Bowers DW GoM (Default)

0.4

Bowers DW GoM (Default)

0.5

Bowers DW GoM (Default)

0.6

Bowers DW GoM (Default)

0.7

Bowers DW GoM (Default)

0.8

Bowers DW GoM (Default)

0.9

Bowers DW GoM (Default)

1.0

Bowers DW GoM (Default)

1.0

γ= 2.0

0.51

KC292-1BP2 Kaskida DW Gulf of Mexico

U.S.A.

0.0

a = 0.51

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.0

γ= 2.0

0.51

RhoVeTM

GCS Solutions, Inc.

geopressure consulting services & solutions

GCS

“leading though innovation”

Advantages “Lead through innovation” Efficiency through simplicity

RhoVe method provides interactive solutions for: Prospect Exploration Prospect Maturation Operations

Advanced pore pressure modeling through a user-friendly application

Conclusions RhoVe method provides interactive solutions Designed on a continuum of “virtual”, normally pressured synthetic rock

properties models Pore pressure is calculated by directly applying RhoVe-derived Velocity &

Density-Effective Stress trends Subsalt Applications and handles varying shale lithologies with multiple NCTs,

such as DWGoM Paleogene (WCX-equivalent) & Offshore Canada (Nova Scotia)

Fundamentally a two-parameter approach (a-term & α); effects of clay diagenesis is captured and utilized empirically for pore pressure analysis.

Consistent with Bower’s Method solutions for DWGoM fine-grained clastics.

140

BackupSlides

Ebrom &Heppard Smectite

Ebrom & Heppard R.O.W.Bowers DW GOM

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.0

DensityNCT

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.1

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.2

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.3

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.35

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.4

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.5

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.6

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.7

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.8

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

0.9

RhoVE-ε

RhoVE-ε

RhoVE-ε

Rhob

1.0

KC292-1BP2 Kaskida DW Gulf of Mexico

U.S.A.

0.0

0.1

0.2

0.3

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

KC292-1BP2 Kaskida DW Gulf of Mexico

U.S.A.

DELIMITED

0.3

0.3

0.4

0.3

0.5

0.3

0.6

0.3

0.7

0.3

0.8

0.3

0.9

0.3

1.0

0.3

Slide 189

RhoVE MethodUn-Tethered Mode

1.00. 1.00.

1.0

0.

1.00. 1.00.

1.00.ESnorm

ESnorm ESnorm

TwoParameter:

(a , α)