In addition to conducting an assessment of the geologic carbon dioxide (CO2) sequestration potential for the Nation, the USGS Geologic Carbon Sequestration Project will conduct relevant research that will be needed to refine the current and future CO2 storage assessments. This research will include: the geochemistry of CO2 interactions with subsurface environments; geologic controls on CO2 storage capacity related to injectivity and formation under- and over-pressure conditions; enhanced oil and gas recovery and CO2 storage potential; research related to CO2 storage in unconventional reservoirs (coal, shale, and mafic rocks); statistical aggregation of assessment results; key issues related to the economics of geologic CO2 sequestration and the CO2 storage potential associated with enhanced oil and gas recovery, and induced seismicity.
Combustion of fossil fuels produces vast quantities of carbon dioxide (CO2), which is well known to be a greenhouse gas. Geologic sequestration of CO2 is one important option to mitigate global warming. Deep saline formations and depleted petroleum fields provide the potential to store large quantities of anthropogenic CO2, allowing long-term or permanent storage of the gas that would otherwise be released to the... [+]
atomosphere. Geochemical studies at on-going CO2 injection sites and at naturally occurring CO2 reservoirs will help to address some of the uncertainties associated with CO2 sequestrations in deep saline formations.
The objectives of the geochemical research task are as follows: 1) to investigate CO2-water-rock interactions applicable to laboratory and field experiments of CO2 sequestration, including mobilization of toxic metals and organics; 2) to modify SOLMINEQ or develop a separate computer package to simulate CO2-water-rock interactions under a wide range of field and experimental conditions, including solution compositions, temperatures and fluid pressures, including CO2 partial pressures; 3) to study naturally occurring CO2 in gas reservoirs to find analogues for CO2 sequestration and to study the long-term effects of CO2 in natural reservoir rocks and fluids. The ultimate goal is to minimize environmental issues, especially groundwater contamination related to CO2 leakage from sequestration reservoirs in depleted petroleum fields and saline formations.
Contact: Burt Thomas
Petrophysical Rock Properties
Petrophysical Rock Properties
In order to conduct more reliable assessments of the CO2 storage potential in sedimentary basins, more research is required for a better understand reservoir porosity, permeability and pressure. Quantification of injectivity and lateral migration rates for geologic sequestration of supercritical CO2 will lead to better prediction of CO2 storage potential by residual trapping in saline formations. Regional mapping of over and... [+]
under-pressured zones is needed to better characterize injectivity capacity at various depths and rock types.
Recent regional work in the Anadarko Basin shows a vast area of underpressuring beneath a regional seal formed by Permian anhydrites and shales. The discharge point for the underpressured aquifers of Pennsylvanian and Mississippian age is along the Nemaha Ridge in central Kansas and Oklahoma. Work by others has also shown underpressure beneath regional seals in the Texas Panhandle and eastern Colorado. The presence of underpressured aquifers has potential impact for CO2 sequestration because of (1) the demonstration of long-lived regional seals, (2) the mapping of discharge areas, and (3) maps of potentiometric surfaces for regional-scale aquifers that can be used to infer migration pathways, and (4) the impact of reduced (less than hydrostatic) aquifer pressure on the injection pressures required for CO2 sequestration. As pressures in confined strata are either poorly documented or undocumented in the midcontinent of the United States, we plan to map the pore pressure in this area. In addition, new subsurface data form the Gulf of Mexico coastal needs to be incorporated into existing models of the distribution of subsurface overpressure areas.
Slideshow: CO2 Fluid Flow Modeling to Derive... the Time Scales of Lateral Fluid Migration - By Lauri Burke [Adobe Flash]
Contact: Phil Nelson
Enhanced Oil and Gas Recovery
Enhanced Oil and Gas Recovery and CO2 Storage Potential
In 2007, the Energy Independence and Security Act (Public Law 110–140) authorized the USGS to conduct a national assessment of geologic storage resources for carbon dioxide. The legislation also asked USGS to estimate the “potential volumes of oil and gas recoverable by injection and sequestration of industrial carbon dioxide in potential sequestration... [+]
formations". There are significant gaps in our understanding about which oil and gas reservoirs are suitable for enhanced oil recovery operations. The purpose of this research task is to identify the geologic and engineering parameters that need to be included in a USGS methodology to evaluate the recoverable hydrocarbon resources and potential CO2 sequestration volumes in existing oil and gas reservoirs in the Nation. To address this issue, a workshop was held in 2011 to identify the key areas of research that need to be undertaken to develop a methodology to estimate the amount of hydrocarbons that might be produced as a result of CO2 geologic sequestration activities. The results of the workshop will be incorporated into a summary report.
Slideshow: Development Philosophy of an Assessment Methodology for Hydrocarbon Recovery Potential Using CO2–EOR Associated with Carbon Sequestration - By Mahendra Verma and Peter Warwick [Adobe Flash]
Contact: Mahendra Verma
Unconventional Reservoirs and CO2 Storage
The current USGS National CO2 assessment measures potential subsurface storage volumes only in existing pore space of sandstones, limestones, or dolostones (Brennan and others, 2010). Other lithologies such as coal, shale, mafic rocks (i.e. basalt), and ultramafic rocks (i.e. peridotite or serpentinite) can trap CO2 through adsorption or mineralogic reaction, but are not addressed in the current assessment... [+]
methodology. More research is needed to understand the physical and chemical CO2
-trapping processes of these unconventional reservoirs before an assessment methodology can be developed and their National storage potential can be assessed. Potential issues of CO2
adsorption in coal and shale include 1) the potential of dissolved organics in CO2
-saturated coal seams or organic-rich layers to become mobilized and mixed with groundwater, 2) the swelling behavior of the coal structure and the loss of permeability in CO2
-saturated coal seams, and 3) the effects of injected CO2
on existing microbial methane producing populations. Potential issues for CO2
storage in mafic or ultramafic include 1) the reaction of CO2
to form stable carbonates; 2) CO2
storage volume dependence on cation content in basalts (different compositions would yield different reaction volumes), and phases present (e.g. olivine or serpentine) in ultramafics; 3) fracture content (a greater fracture density would allow greater surface area of reaction), and 4) groundwater quality. The primary objectives for this task is to hold workshops and compile reports summarizing the state of knowledge concerning the use of coal seams, shale, and mafic/ultramafic rocks as a potential reservoirs for the long-term storage of CO2
, and suggest preliminary methodologies for future assessments.
Contact: Kevin Jones
Economics of CO2
Enhanced Oil Recovery
Economics of CO2 Storage and Enhanced Oil Recovery
Resource assessments need an economic analysis of the results to help policy makers and other assessment users better understand the potential development of the resource under various economic conditions. Because geologic carbon sequestration is relatively new, few studies have been conducted on the economic viability of wide-spread implementation of the... [+]
technology. Also, previous economic assessments of enhanced hydrocarbon recovery using CO2 have focused on the economics of the recoverable hydrocarbons and have not included an assessment of the economic viability of carbon dioxide sequestration associated with the enhanced hydrocarbon recovery processes. Efforts undertaken in this research task will be coordinated with the Energy Resources Program - Economics dimensions of energy resources, assessments and future supply project. The focus of this research task will be to help develop the economic models needed to evaluate 1) the results of the 2013 USGS national assessment of geologic carbon dioxide storage resources with a focus on buoyant traps - the CO2 storage resource with the most supporting data and the most likely to be developed; and 2) the potential for incremental oil recovery and associated CO2 sequestration in oil fields in the lower 48 states that pass an engineering and geologic screening test for carbon dioxide – enhanced oil recovery (CO2-EOR) application.
Contact: Phil Freeman
The objective of the induced seismicity task is to support interdisciplinary research on the potential impacts of induced seismicity on geologic carbon sequestration in conjunction with parallel efforts supported by the USGS Geothermal Resource Investigations Project and the Earthquake Hazards Program. There is a potential seismic hazard associated with geologic carbon sequestration projects, which could involve the... [+]
injection of vast quantities of CO2 into sedimentary basins located in or near major urban centers of the United States. A multidisciplinary approach including research in seismology, crustal deformation, reservoir rock properties, in situ stress and fracture permeability, heat transport, fluid flow and other study areas will be used to develop a better understanding of the physical processes responsible for induced seismicity. A few research examples include 1) determining the distribution of earthquake frequency of occurrence as a function of magnitude that is likely to result from a specified injection operation, 2) determining the magnitude of the largest induced earthquake from a specific injection operation, 3) determining the probability of ground motion exceeding a given level and significant injury or structural damage at a particular site due to induced earthquakes, and 4) determining if earthquakes induced by deep fluid-injection and production operations can be influenced by altering operational procedures in ways that do not compromise project objectives.
Contact: Stephen Hickman
Contact: Art McGarr
The objective of this research task is to develop statistical methods to aggregate storage assessment capacity estimates to a basin and national scale for the National Geologic Carbon Dioxide Sequestration Assessment Project results. This work involved cooperation with statisticians who have worked on the USGS National Oil and Gas Assessment and the World Oil and Gas Assessment projects... [+]
View a poster [.pdf] prepared for presention at the 34th International Geological Congress, Brisbane, Australia, August 5-10, 2012
USGS Professional Profile