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The Foote Creek and Dutton Creek Formations, Two New Formations in the North Part of the Laramie Basin, Wyoming

Description: A report about two new geologic formations in Wyoming. The Foote Creek Formation consists of beds of fine-grained sandstone with shale, siltstone, and coal beds. The Dutton Creek Formation consists of beds of coarse-grained locally conglomeratic sandstone.
Date: 1965
Creator: Hyden, Harold J.; McAndrews, Harry & Tschudy, Robert H.
Partner: UNT Libraries Government Documents Department

ER-12-1 completion report

Description: The objective of drillhole ER-12-1 was to determine the hydrogeology of paleozoic carbonate rocks and of the Eleana Formation, a regional aquitard, in an area potentially downgradient from underground nuclear testing conducted in nearby Rainier Mesa. This objective was addressed through the drilling of well ER-12-1 at N886,640.26 E640,538.85 Nevada Central Coordinates. Drilling of the 1094 m (3588 ft) well began on July 19, 1991 and was completed on October 17, 1991. Drilling problems included hole deviation and hole instability that prevented the timely completion of this borehole. Drilling methods used include rotary tri-cone and rotary hammer drilling with conventional and reverse circulation using air/water, air/foam (Davis mix), and bentonite mud. Geologic cuttings and geophysical logs were obtained from the well. The rocks penetrated by the ER-12-1 drillhole are a complex assemblage of Silurian, Devonian, and Mississippian sedimentary rocks that are bounded by numerous faults that show substantial stratigraphic offset. The final 7.3 m (24 ft) of this hole penetrated an unusual intrusive rock of Cretaceous age. The geology of this borehole was substantially different from that expected, with the Tongue Wash Fault encountered at a much shallower depth, paleozoic rocks shuffled out of stratigraphic sequence, and the presence of an altered biotite-rich microporphyritic igneous rock at the bottom of the borehole. Conodont CAI analyses and rock pyrolysis analyses indicate that the carbonate rocks in ER-12-1, as well as the intervening sheets of Eleana siltstone, have been thermally overprinted following movement on the faults that separate them. The probable source of heat for this thermal disturbance is the microporphyritic intrusion encountered at the bottom of the hole, and its age establishes that the major fault activity must have occurred prior to 102.3+0.5 Ma (middle Cretaceous).
Date: December 1, 1996
Creator: Russell, C.E.; Gillespie, D.; Cole, J.C. & Drellack, S.L.
Partner: UNT Libraries Government Documents Department

Geologic map of Paleozoic rocks in the Calico Hills, Nevada Test Site, southern Nevada

Description: The Calico Hills area in the southwestern part of the Nevada Test Site, Nye County, Nevada, exposes a core of pre-Tertiary rocks surrounded by middle Miocene volcanic strata. This map portrays the very complex relationships among the pre-Tertiary stratigraphic units of the region. The Devonian and Mississippian rocks of the Calico Hills are distinct from age-equivalent carbonate-shelf or submarine-fan strata in other parts of the Nevada Test Site. The Calico Hills strata are interpreted to have been deposited beyond the continental shelf edge from alternating silicic and carbonate clastic sources. Structures of the Calico Hills area record the compounded effects of: (1) eastward-directed, foreland-vergent thrusting; (2) younger folds, kink zones, and thrusts formed by hinterland-vergent deformation toward northwesterly and northerly directions; and (3) low-angle normal faults that displaced blocks of Middle Paleozoic carbonate strata across the contractionally deformed terrane. All of these structures are older than any of the middle Miocene volcanic rocks that were erupted across the Calico Hills.
Date: November 1, 1998
Creator: Cole, J.C. & Cashman, P.H.
Partner: UNT Libraries Government Documents Department

Colloid Transport and Retention in Fractured Media

Description: The goal of this project was to identify the chemical and physical factors that control the transport of colloids in fractured materials, and develop a generalized capability to predict colloid attachment and detachment based on hydraulic factors (head, flow rate), physical processes and structure (fracture aperture, matrix porosity), and chemical properties (surface properties of colloids, solution chemistry, and mineralogy of fracture surfaces). Both aqueous chemistry and physical structure of geologic formations influenced transport. Results of studies at all spatial scales reached consensus on the importance of several key controlling variables: (1) colloid retention is dominated by chemical conditions favoring colloid-wall interactions; (2) even in the presence of conditions favorable to colloid collection, deposited colloids are remobilized over long times and this process contributes substantially to the overall extent of transport; (3) diffusive exchange between water-conducting fractures and finer fractures and pores acts to ''buffer'' the effects of the major fracture network structure, and reduces predictive uncertainties. Predictive tools were developed that account for fundamental mechanisms of colloid dynamics in fracture geometry, and linked to larger-scale processes in networks of fractures. The results of our study highlight the key role of physical and hydrologic factors, and processes of colloid remobilization that are potentially of even greater importance to colloid transport in the vadose zone than in saturated conditions. We propose that this work be extended to focus on understanding vadose zone transport processes so that they can eventually be linked to the understanding and tools developed in our previous project on transport in saturated groundwater systems.
Date: February 2001
Creator: McCarthy, J. F.
Partner: UNT Libraries Government Documents Department

Interpreting Fracture Patterns in Sandstones Interbedded with Ductile Strata at the Salt Valley Anticline, Arches National Park, Utah

Description: Sandstones that overlie or that are interbedded with evaporitic or other ductile strata commonly contain numerous localized domains of fractures, each covering an area of a few square miles. Fractures within the Entrada Sandstone at the Salt Valley Anticline are associated with salt mobility within the underlying Paradox Formation. The fracture relationships observed at Salt Valley (along with examples from Paleozoic strata at the southern edge of the Holbrook basin in northeastern Arizona, and sandstones of the Frontier Formation along the western edge of the Green River basin in southwestern Wyoming), show that although each fracture domain may contain consistently oriented fractures, the orientations and patterns of the fractures vary considerably from domain to domain. Most of the fracture patterns in the brittle sandstones are related to local stresses created by subtle, irregular flexures resulting from mobility of the associated, interbedded ductile strata (halite or shale). Sequential episodes of evaporite dissolution and/or mobility in different directions can result in multiple, superimposed fracture sets in the associated sandstones. Multiple sets of superimposed fractures create reservoir-quality fracture interconnectivity within restricted localities of a formation. However, it is difficult to predict the orientations and characteristics of this type of fracturing in the subsurface. This is primarily because the orientations and characteristics of these fractures typically have little relationship to the regional tectonic stresses that might be used to predict fracture characteristics prior to drilling. Nevertheless, the high probability of numerous, intersecting fractures in such settings attests to the importance of determining fracture orientations in these types of fractured reservoirs.
Date: December 1, 2001
Partner: UNT Libraries Government Documents Department

An Integrated Study of the Grayburg/San Andres Reservoir, Foster and South Cowden Fields, Ector County, Texas

Description: The goals of work done this quarter were (1) to analyze the preliminary seismic inversion model for the Grayburg A, B, and C sequences and the upper San Andres formation; (2) modify the inversion model to improve its accuracy and to include the deeper Holt Formation; and (3) test various rock property quantities against the improved model and other seismic attributes using refined analysis boundaries. A satisfactory inversion model and porosity analysis remains to be accomplished, but much has been learned about the modeling and analysis processes. Qualitative comparison of sonic logs with the inversion model traces in profile view shows great similarity and success is being made toward good quantitative results.
Date: May 28, 1998
Creator: Weinbrandt, R.; Trentham, R.C. & Robertson, W.
Partner: UNT Libraries Government Documents Department

3-D Seismic Exploration Project, Ute Indian Tribe, Uintah and Ouray Reservation, Uintah County, Utah

Description: The objectives of this North Hill Creek 3-D seismic survey were to: (1) cover as large an area as possible with available budget; (2) obtain high quality data throughout the depth range of the prospective geologic formations of 2,000' to 12,000' to image both gross structures and more subtle structural and stratigraphic elements; (3) overcome the challenges posed by a hard, reflective sandstone that cropped out or was buried just a few feet below the surface under most of the survey area; and (4) run a safe survey.
Date: September 9, 2002
Creator: Eckels, Marc T.
Partner: UNT Libraries Government Documents Department

The consequences of failure should be considered in siting geologic carbon sequestration projects

Description: Geologic carbon sequestration is the injection of anthropogenic CO{sub 2} into deep geologic formations where the CO{sub 2} is intended to remain indefinitely. If successfully implemented, geologic carbon sequestration will have little or no impact on terrestrial ecosystems aside from the mitigation of climate change. However, failure of a geologic carbon sequestration site, such as large-scale leakage of CO{sub 2} into a potable groundwater aquifer, could cause impacts that would require costly remediation measures. Governments are attempting to develop regulations for permitting geologic carbon sequestration sites to ensure their safety and effectiveness. At present, these regulations focus largely on decreasing the probability of failure. In this paper we propose that regulations for the siting of early geologic carbon sequestration projects should emphasize limiting the consequences of failure because consequences are easier to quantify than failure probability.
Date: February 23, 2009
Creator: Price, P.N. & Oldenburg, C.M.
Partner: UNT Libraries Government Documents Department

On Leakage from Geologic Storage Reservoirs of CO2

Description: Large amounts of CO2 would need to be injected underground to achieve a significant reduction of atmospheric emissions. The large areal extent expected for CO2 plumes makes it likely that caprock imperfections will be encountered, such as fault zones or fractures, which may allow some CO2 to escape from the primary storage reservoir. Leakage of CO2 could also occur along wellbores. Concerns with escape of CO2 from a primary geologic storage reservoir include (1) acidification of groundwater resources, (2) asphyxiation hazard when leaking CO2 is discharged at the land surface, (3) increase in atmospheric concentrations of CO2, and (4) damage from a high-energy, eruptive discharge (if such discharge is physically possible). In order to gain public acceptance for geologic storage as a viable technology for reducing atmospheric emissions of CO2, it is necessary to address these issues and demonstrate that CO2 can be injected and stored safely in geologic formations.
Date: February 14, 2006
Creator: Pruess, Karsten
Partner: UNT Libraries Government Documents Department

Predicting and Evaluating the Effectiveness of Ocean Carbon Sequestration by Direct Injection

Description: Direct injection of CO{sub 2} into the ocean is a potentially effective carbon sequestration strategy. Therefore, we want to understand the effectiveness of oceanic injection and develop the appropriate analytic framework to allow us to compare the effectiveness of this strategy with other carbon management options. Here, after a brief review of direct oceanic injection, we estimate the effectiveness of ocean carbon sequestration using one dimensional and three dimensional ocean models. We discuss a new measure of effectiveness of carbon sequestration in a leaky reservoir, which we denote sequestration potential. The sequestration potential is the fraction of global warning cost avoided by sequestration in a reservoir. We show how these measures apply to permanent sequestration and sequestration in leaky reservoirs, such as the oceans, terrestrial biosphere, and some geologic formations. Under the assumptions of a constant cost of carbon emission and a 4% discount rate, injecting 900 m deep in the ocean avoids {approx}90% of the global warming cost associated with atmospheric emission; an injection 1700 m deep would avoid > 99 % of the global warming cost. Hence, for discount rates in the range commonly used by commercial enterprises, oceanic direct injection may be nearly as economically effective as permanent sequestration at avoiding global warming costs.
Date: April 24, 2001
Creator: Caldeira, K; Herzog, H J & Wickett, M E
Partner: UNT Libraries Government Documents Department

DECOVALEX-THMC Task D: Long-Term Permeability/Porosity Changes inthe EDZ and Near Field due to THM and THC Processes in Volcanic andCrystaline-Bentonite Systems, Status Report October 2005

Description: The DECOVALEX project is an international cooperativeproject initiated by SKI, the Swedish Nuclear Power Inspectorate, withparticipation of about 10 international organizations. The name DECOVALEXstands for DEvelopment of COupled models and their VALidation againstExperiments. The general goal of this project is to encouragemultidisciplinary interactive and cooperative research on modelingcoupled processes in geologic formations in support of the performanceassessment for underground storage of radioactive waste. Three multi-yearproject stages of DECOVALEX have been completed in the past decade,mainly focusing on coupled thermal-hydrological-mechanicalprocesses.Currently, a fourth three-year project stage of DECOVALEX isunder way, referred to as DECOVALEX-THMC. THMC stands for Thermal,Hydrological, Mechanical, and Chemical processes. The new project stageaims at expanding the traditional geomechanical scope of the previousDECOVALEX project stages by incorporating geochemical processes importantfor repository performance. The U.S. Department of Energy (DOE) leadsTask D of the new DECOVALEX phase, entitled "Long-termPermeability/Porosity Changes in the EDZ and Near Field due to THC andTHM Processes for Volcanic and Crystalline-Bentonite Systems." In itsleadership role for Task D, DOE coordinates and sets the direction forthe cooperative research activities of the international research teamsengaged in Task D.
Date: November 1, 2005
Creator: Birkholzer, J.; Rutqvist, J.; Sonnenthal, E. & Barr, D.
Partner: UNT Libraries Government Documents Department

The Rosetta Resources CO2 Storage Project - A WESTCARB GeologicPilot Test

Description: WESTCARB, one of seven U.S. Department of Energypartnerships, identified (during its Phase I study) over 600 gigatonnesof CO2 storage capacity in geologic formations located in the Westernregion. The Western region includes the WESTCARB partnership states ofAlaska, Arizona, California, Nevada, Oregon and Washington and theCanadian province of British Columbia. The WESTCARB Phase II study iscurrently under way, featuring three geologic and two terrestrial CO2pilot projects designed to test promising sequestration technologies atsites broadly representative of the region's largest potential carbonsinks. This paper focuses on two of the geologic pilot studies plannedfor Phase II -referred to-collectively as the Rosetta-Calpine CO2 StorageProject. The first pilot test will demonstrate injection of CO2 into asaline formation beneath a depleted gas reservoir. The second test willgather data for assessing CO2 enhanced gas recovery (EGR) as well asstorage in a depleted gas reservoir. The benefit of enhanced oil recovery(EOR) using injected CO2 to drive or sweep oil from the reservoir towarda production well is well known. EaR involves a similar CO2 injectionprocess, but has received far less attention. Depleted natural gasreservoirs still contain methane; therefore, CO2 injection may enhancemethane production by reservoir repressurization or pressure maintenance.CO2 injection into a saline formation, followed by injection into adepleted natural gas reservoir, is currently scheduled to start inOctober 2006.
Date: January 30, 2006
Creator: Trautz, Robert; Benson, Sally; Myer, Larry; Oldenburg, Curtis; Seeman, Ed; Hadsell, Eric et al.
Partner: UNT Libraries Government Documents Department

Motivation, description, and summary status of geomechanical andgeochemical modeling studies in Task D of the InternationalDECOVALEX-THMC Project

Description: The DECOVALEX project is an international cooperativeproject initiated by SKI, the Swedish Nuclear Power Inspectorate, withparticipation of about 10 international organizations. The general goalof this project is to encourage multidisciplinary interactive andcooperative research on modelling coupledthermo-hydro-mechanical-chemical (THMC) processes in geologic formationsin support of the performance assessment for underground storage ofradioactive waste. One of the research tasks, initiated in 2004 by theU.S. Department of Energy (DOE), addresses the long-term impact ofgeomechanical and geochemical processes on the flow conditions near wasteemplacement tunnels. Within this task, four international research teamsconduct predictive analysis of the coupled processes in two genericrepositories, using multiple approaches and different computer codes.Below, we give an overview of the research task and report its currentstatus.
Date: November 15, 2005
Creator: Birkholzer, J.T.; Barr, D.; Rutqvist, J. & Sonnenthal, E.
Partner: UNT Libraries Government Documents Department

Natural CO2 Analogs for Carbon Sequestration

Description: The report summarizes research conducted at three naturally occurring geologic CO{sub 2} fields in the US. The fields are natural analogs useful for the design of engineered long-term storage of anthropogenic CO{sub 2} in geologic formations. Geologic, engineering, and operational databases were developed for McElmo Dome in Colorado; St. Johns Dome in Arizona and New Mexico; and Jackson Dome in Mississippi. The three study sites stored a total of 2.4 billion t (46 Tcf) of CO{sub 2} equivalent to 1.5 years of power plant emissions in the US and comparable in size with the largest proposed sequestration projects. The three CO{sub 2} fields offer a scientifically useful range of contrasting geologic settings (carbonate vs. sandstone reservoir; supercritical vs. free gas state; normally pressured vs. overpressured), as well as different stages of commercial development (mostly undeveloped to mature). The current study relied mainly on existing data provided by the CO{sub 2} field operator partners, augmented with new geochemical data. Additional study at these unique natural CO{sub 2} accumulations could further help guide the development of safe and cost-effective design and operation methods for engineered CO{sub 2} storage sites.
Date: July 31, 2005
Creator: Stevens, Scott H. & Tye, B. Scott
Partner: UNT Libraries Government Documents Department

Use of the 1991 ASCOT field study data in a mesoscale model employing a four-dimensional data assimilation technique

Description: In this study, a four-dimensional data assimilation technique based on Newtonian relaxation is incorporated into Colorado State University (CSU) Regional Atmospheric Modeling System (RAMS) and evaluated using data taken from one experiment of the US Department of Energy's (DOE) 1991 Atmospheric Studies in COmplex Terrain (ASCOT) field study along the front range of the Rockies in Colorado. The main objective of this study is to determine the ability of the model to predict small-scale circulations influenced by terrain, such as drainage flows, and assess the impact of data assimilation on the numerical results. In contrast to previous studies in which the smallest horizontal grid spacing was 10 km (Stauffer and Seaman, 1991) and 8 km (Yamada and Hermi, 1991), data assimilation is applied in this study to domains with a horizontal grid spacing as small as 1 km. The prognostic forecasts made by RAMS are evaluated by comparing simulations that employ static initial conditions, with simulations that incorporate continuous data assimilation and data assimilation for fixed period of time (dynamic initialization). This paper will also elaborate on the application and limitation of the Newtonian relaxation technique in limited-area mesoscale models with a relatively small grid spacing.
Date: January 1, 1992
Creator: Fast, J.D. & O'Steen, B.L.
Partner: UNT Libraries Government Documents Department

Response to: “Long-term effectiveness and consequences of carbon dioxide sequestration” by Gary Shaffer, published in Nature Geosciences, 27 June 2010.

Description: Shaffer’s (2010) article reports on the long term impact of less than perfect retention of anthropogenic CO2 stored in deep geologic reservoirs and in the ocean. The central thesis of this article is predicated on two deeply flawed assumptions. The first and most glaring is the implicit assumption that society has only one means of reducing greenhouse gas emissions, carbon dioxide capture and storage (CCS). Secondly, there is absolutely no geophysical nor geomechanical basis for assuming an exponential decay of CO2 stored in deep geologic formations as done by Schaffer. Shaffer’s analysis of the impact of leakage from anthropogenic CO2 stored in deep geologic reservoirs are based upon two fundamentally flawed assumptions and therefore the reported results as well as the public policy conclusions presented in the paper need to be read with this understanding in mind as far less CO2 stored below ground because society drew upon a broad portfolio of advanced energy technologies over the coming century coupled with a more technically accurate conceptualization of CO2 storage in the deep subsurface and the important role of secondary and tertiary trapping mechanisms would have yield a far less pessimistic view of the potential role that CCS can play in a broader portfolio of societal responses to the very serious threat posed by climate change.
Date: July 12, 2010
Creator: Dooley, James J.
Partner: UNT Libraries Government Documents Department

Valley filled sand stones In a kootenai formation on the Crow Indian Reservation South Central Montana: Quarterly technical report, January 1, 1997--March 31, 1997

Description: Field investigation of the Kootenai valley-fill sandstones was begun in the first quarter. About one half of the outcrop belt was inventoried for occurrences of channel sandstone before heavy snows came to the area. Five exposures of valley-fill sandstone have been located, of these two are 15 meters (50 feet) or greater in thickness and have excellent porosity and permeability. These will be measured and studied in detail during the next field season (1997). No further field work was possible during the second and third quarters because of snow cover. Subsurface data is being collected, organized, and a digital database is being prepared for the project. Geographix petroleum software will probably be used to manage and manipulate the data. Regional subsurface cross sections are being constructed for correlation purposes. All of the four 30 X 60 geologic quadrangles, the Billings, Bridger, Hardin, and Lodge Grass, have been scanned to produce a digital surface geologic data base for the Crow Reservation. These maps are currently being proofed and edited for accuracy. A four-day oil and gas training seminar for Crow Tribal members was completed and was quite successful. The purpose was to enable tribal members and employees to understand and evaluate potential exploration prospects and offers that may result from the completion of this research project.
Date: April 4, 1997
Creator: Lopex, D.A.
Partner: UNT Libraries Government Documents Department

Valley-Fill Sandstones in the Kootenai Formation on the Crow Indian Reservation, South Central Montana.

Description: Subsurface data is being collected, organized, and a digital database is being prepared for the project. An ACCESS database and PC-Arcview will be used to manage and interpret the data. All of the four 30 X 60 geologic quadrangles have been scanned to produce a digital surface geologic data base for the Crow Reservation and all are nearing completion. Writing of the map explanations has begun. Field investigations were nearly completed during this quarter; only minor field checks remain. With the help of a student field assistant from the Crow Tribe, the entire project area was inventoried for the presence of valley-fill deposits in the Kootenai Formation. Field inventory has resulted in the identification of nine exposures of thick valley-fill deposits. These appear to represent at least four major westward-trending valley systems. All the channel localities have been measured and described in detail and paleocurrent data has been collected from all but one locality. In addition, two stratigraphic sections were measured in areas where channels are absent.
Date: October 1, 1997
Creator: Lopez, D.A.
Partner: UNT Libraries Government Documents Department

Automatic Calibration of Geothermal Reservoir Models Through Parallel Computing on a Workstation Cluster

Description: ITOUGH2 is an optimization code that allows estimation of any input parameter of the nonisothermal, multiphase flow simulator TOUGH2. ITOUGH2 inversions are computationally intensive because the so-called forward problem, i.e., the simulation of fluid and heat flow through the geologic formation, must be solved many times for different parameter combinations to evaluate the misfit criterion or to numerically calculate sensitivity coefficients. Most of these forward runs am independent from each other and can therefore be performed in parallel. Message passing based on the Parallel Virtual Machine (PVM) system has been implemented into ITOUGH2 to enable parallel processing of forward simulations on a heterogeneous network of Unix workstations or networked PCs that run under the Linux operating system. This paper describes the PVM system and its implementation into ITOUGH2. Examples are discussed, demonstrating the use, efficiency, and limitations of ITOUGH2-PVM.
Date: January 1, 1999
Creator: Finsterle, S. & Pruess, K.
Partner: UNT Libraries Government Documents Department