PETROPHYSICAL SPREAD SHEET TUTORIAL
INTRODUCTION
An excel workflow using data from the reservoir flow units (FU) established by observing the log curves and core analysis data. A data set from Weyburn Field carbonate demonstrates the use of the spread sheet. The purpose of the spread sheet is to: a) Process selected data most representative of a layer (FU) of rock. This is an interval of rock with constant attributes
(porosity log curves, resistivity curves, Ka/Phi ratio, etc.).
b) Compute porosity, Sw, Rwa and hydrocarbon in place.
c) Prepare relevant plots to integrate log data, log to core data and determine pore geometry and
flow potential.
DATA ENTRY
Column Action
A Constants used in the Archie equation: -Rmf - From log header corrected to formation temperature. -Rw - From produced water, SP curve or Ro zone. -Fm. Temp. - Corrected from BHT to formation temperature. -n - Saturation Exponent -a - Constant = 1
B FU - Flow Unit Numbers (FU)
C Depth - Depth at top of FU
D h - Flow Unit Thickness
E Neutron Porosity (Ls) or appropriate matrix
F Bulk Density or porosity at appropriate matrix
G Rt - Deep Resistivity (corrected for bed thickness and invasion)
H Porosity, estimated from D/N plot, or other source.
I Pef - lithology from photo electric effect of Density Log.
J m - cementation exponent varies with clay content of vuggy Phi.
K Rwa - computed quick look for pay from porosity and resistivity.
L Sw - computed from Archie transform.
M Sxo - computed from Archie in the flush zone (using Ro).
N BVW - product of porosity and Sw.
O MHV - Hydrocarbon Mobility
P Area - drainage area in acres.
Q HPV - Hydrocarbon Pore Volume
R RE - Recovery Efficiency for drainage area.
S Rec. Hyd. - Recoverable Hydrocarbon = reserves
T Depth
U Height - feet above water table.
V r35 - pore throat size computed from porosity and air permeability.
INTRODUCTION
An excel workflow using data from the reservoir flow units (FU) established by observing the log curves and core analysis data. A data set from Weyburn Field carbonate demonstrates the use of the spread sheet. The purpose of the spread sheet is to: a) Process selected data most representative of a layer (FU) of rock. This is an interval of rock with constant attributes
(porosity log curves, resistivity curves, Ka/Phi ratio, etc.).
b) Compute porosity, Sw, Rwa and hydrocarbon in place.
c) Prepare relevant plots to integrate log data, log to core data and determine pore geometry and
flow potential.
DATA ENTRY
Column Action
A Constants used in the Archie equation: -Rmf - From log header corrected to formation temperature. -Rw - From produced water, SP curve or Ro zone. -Fm. Temp. - Corrected from BHT to formation temperature. -n - Saturation Exponent -a - Constant = 1
B FU - Flow Unit Numbers (FU)
C Depth - Depth at top of FU
D h - Flow Unit Thickness
E Neutron Porosity (Ls) or appropriate matrix
F Bulk Density or porosity at appropriate matrix
G Rt - Deep Resistivity (corrected for bed thickness and invasion)
H Porosity, estimated from D/N plot, or other source.
I Pef - lithology from photo electric effect of Density Log.
J m - cementation exponent varies with clay content of vuggy Phi.
K Rwa - computed quick look for pay from porosity and resistivity.
L Sw - computed from Archie transform.
M Sxo - computed from Archie in the flush zone (using Ro).
N BVW - product of porosity and Sw.
O MHV - Hydrocarbon Mobility
P Area - drainage area in acres.
Q HPV - Hydrocarbon Pore Volume
R RE - Recovery Efficiency for drainage area.
S Rec. Hyd. - Recoverable Hydrocarbon = reserves
T Depth
U Height - feet above water table.
V r35 - pore throat size computed from porosity and air permeability.
DJH Energy Consulting
Dan J. Hartmann
P.O. Box 271
Fredericksburg, Tx 78624
210-508-7455
djhec@ktc.com
Dan J. Hartmann
P.O. Box 271
Fredericksburg, Tx 78624
210-508-7455
djhec@ktc.com
