MRCSP Phase I Geologic Characterization Report - Midwest ...

CONCLUSIONS AND REGIONAL ASSESSMENT FOR GEOLOGIC SEQUESTRATION
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CONCLUSIONS AND REGIONAL ASSESSMENT FOR GEOLOGIC SEQUESTRATION
Under Subtask 2.1 of the MRCSP Phase I project, the geologic
team examined the region’s overall geology, created a regional
correlation chart, and delineated the most promising prospective
geologic CO 2 reservoirs and sinks via data collation, interpretation,
and mapping. We then used the collected data and maps to calculate
a first approximation of the region’s geologic CO 2 sequestration
capacities of four main reservoir classes: deep saline formations, oil
and gas fields, unmineable coalbeds, and organic shales. The deep
saline formations, especially the Mt. Simon, St. Peter, and Rose Run
sandstones, are, by far, the region’s largest assets for long-term geologic
CO 2 sequestration. All of this information has been captured in
a Geographic Information System using ESRI’s suite of ARC-GIS
products.
Through these efforts we have also defined a number of promising
additional sequestration target formations including the Bass
Islands Dolomite, Lockport Dolomite, and Copper Ridge Dolomite.
These will be mapped and analyzed as separate units within the
Phase II project to complete the region’s assessment. During Phase
II the geologic team will also develop more comprehensive data on
the region’s EOR potential, Class I and II injection wells, and gas
storage fields. All of these data are necessary to provide a sound
knowledge basis for moving forward with widespread implementation
of geologic CO 2 sequestration.
This Phase I assessment has shown that the MRCSP region has
approximately 450 to 500 gigatonnes of storage potential in deep saline
formations for future deployment of geologic CO 2 sequestration
technology. In fact, our region can easily accommodate many hundreds
of year’s worth of CO 2 emissions at current or expanded levels
within this one type of reservoir. This region also has the potential to
store at least 2.5 giggatones of CO 2 in existing and depleted oil and
gas fields. By using anthropogenic CO 2 in enhanced oil recovery
operations in current and recently abandoned oil fields, the region
could realize hundreds of million of barrels of additional oil production.
The northern Appalachian basin unmineable coalbeds have the
potential to contain approximately 0.25 gigatonnes of CO 2. Only recently
have operators started to develop the vast amount of coalbed
methane found beneath the northern Appalachian basin. Application
of enhanced gas recovery using CO 2 early in this endeavor could
add significantly to the amount of gas produced from the deep unmineable
portions of this resource while sequestering millions of
tons of CO 2 in its place. The use of organic shales as a CO 2-storage
medium is still an untested research topic. Should this technology
prove practical, the MRCSP region has one of the richest holdings
of these deposits in the world.
Although we are herein reporting capacities of reservoirs at 10
percent of total assumed volumes, we do not believe these estimates
to be sufficiently conservative. It should also be kept in mind that
many other restrictions will be emplaced on the use of any subsurface
storage space that have not been accounted for in studies of
this type to date. Such restrictions, or access issues, might include:
inability to inject below large metropolitan areas or large bodies
of water; inability to inject below or within specific offsets (both
vertically and horizontally) of producing oil and gas fields or active
mines; and the inability to inject within specific offsets (both vertically
and horizontally) of other injection operations—Class I, II, or
III. In addition to these listed possible restrictions, the consideration
that large-scale CO 2 injection operations should not be permitted too
close to one another to avoid any possibility of interaction of their
related pressure fronts should be stressed. Many of these restrictions
will fall under the purview of regulatory agencies to enact. As with
the entire carbon capture and storage technology arena, regulations
for CO 2 injection and storage are still in an early formative stage.
Once regulations are known, restrictions can be applied to these capacity
maps to calculate potentials including such considerations.
The above-cited storage potential is not distributed evenly over
the region. Some areas have very significant storage potential while
others have very little known storage potential. Mapping the distribution
of this potential is just as significant to the region as calculating
the potential for storage. The existing large stationary CO 2
sources of the region are not all situated over sufficient known storage
potential. Therefore, it is hoped that this study, and subsequent
investigations, will be used by utility and industrial decision-makers
to plan future plant locations with necessary subsurface conditions
in mind. Further, the maps/results of this investigation can be used
to start planning for future pipelines to match existing CO 2 sources
with appropriate geologic sinks.