A
lthough the recent commodity price fluctuations have exposed the role of geo-politics,
world economies and commodity trading in the life cycle of assets, a limited number
of field development studies have considered the impact of commodity cycles on the
development of in-fill wells. These commodity price fluctuations have resulted in a reduction
in drilling and completions activities across the United States. This further implies that in
most unconventional plays throughout the US, in-fill well completion (and thus production)
will be delayed. This article highlights some of the considerations that should be made when
evaluating the well completion strategy with focus on two unconventional plays, the Bakken
and the Eagle Ford.
The key objective of studying the Bakken and Eagle Ford was to model the well
performance of the parent wells with the aim of predicting in-fill well performance.
Petrophysical and Geomechanical models were developed using data-rich parent well
data-sets. Based on the calibration data available (core and logs) numerous static models
are generated to capture the range of possible interpretations that honour the calibration
data. These models were validated with more calibration data in completions and reservoir
domains to reduce the uncertainty space via history matching real data (production or
fracture treatments). Once, the parent well models have been validated (by matching well
performance history), in-fill modelling and optimisation can proceed. Since the two assets
(Bakken and Eagle Ford) are at significantly different portions of the development cycle, the
Bakken dataset has the luxury of modelling and matching the performance of the parent
and in-fill wells whereas, the Eagle Ford portion of this study focuses primarily on forward
modelling and optimising the in-fill well completions.
Bakkensystemparentwellmodelling
Petrophysics
Petrophysical evaluation indicates that the average of porosity and water saturation is
8% and 50% respectively for the Middle Bakken. Average Klinkenberg permeability for the
Bilu V. Cherian, Sanjel Corporation, Mathew McCleary
and Samuel Fluckiger, SM Energy, discuss challenges of
in-fill development.
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