Sample Heavy Oil
Screening Study
Prepared For Epsilon Energy LTD.
3-31-2009
Gemini Solutions Inc.
James L Buchwalter, P.E./PhD.
Goal Of Sample Heavy Oil
Screening Study

Build model with crude properties similar
to those found in the heavy Syrian Crude
– Guess properties to allow vertical well rates of
20 BOPD with 11 API crude

Run sensitivities to reservoir temperature
increase from steam flood , horizontal
versus vertical wells, and pattern aspect
ratio and development size
– These sensitivities can be used to understand
probable flow streams, economics, and rank
multiple prospects in a consistent fashion
Basic Model Assumptions

Rock properties
Basic Model Assumptions

pvt properties
Basic Model Assumptions
Kr properties
 20% water
saturation

Basic Model Assumptions

Pattern Model
Setup
Well Production Profile, 20 years
160 acres, no steam, vertical well
Well Production Profile, 20 years
160 acres, no steam, vertical well
Sensitivity – Horizontal Well
160 acres, 3/1 aspect ratio, 3000 feet long
blue [=] horizontal well, green [=] vertical well
Recovery increase 4 fold !!
Sensitivity – Horizontal Well
160 acres, 3/1 aspect ratio, 3000 feet long
Recovery increase 4 fold, 5% recovery factor !!
Horizontal Well
Pressures after 20 years
160 acres, 3/1 aspect ratio, 3000 feet long
Heat Oil With Steam

Original PVT and
revised PVT on
right
– Oil viscosity drops
from 71 cp to 13 cp
at the bubble point
6
fold increase in
rate through
viscosity reduction
Temperature Sensitivity – 160 acres
Vertical well [=] blue, vertical well + 180F, green
4 fold increase in recovery!
Temperature Sensitivity – 160 acres
Horizontal well [=] blue, horizontal well + 180F, green
10 fold increase in recovery!
Horizontal Well Versus Vertical Well
+Steam
Both scenarios have similar profiles
Perhaps as alternative to steam horizontal well technology
may be feasible (if vertical permeability sufficient)
Closing Comments




A base model can be built and history matched
A series of sensitivity models can be created to
understand the best drilling and completion
strategy for a field
Screening models are adequate for ranking
prospects and determining potential recovery
factors and well drilling/completion strategies
More precise thermal project design requires a
true thermal simulator and this is recommended
for the final field design
– Suggest CMG Stars simulator
– This work will be an order of magnitude more expensive
than the screening studies and take far longer