Previously conducted preliminary investigations within the deep Delaware and Val Verde sub-basins of the Permian Basin complex documented bottom hole temperatures from oil and gas wells that reach the 120-180C temperature range, and occasionally beyond. With large abundances of subsurface brine water, and known porosity and permeability, the deep carbonate strata of the region possess a good potential for future geothermal power development. This work was designed as a 3-year project to investigate a new, undeveloped geographic region for establishing geothermal energy production focused on electric power generation. Identifying optimum geologic and geographic sites for converting depleted deep gas wells and fields within a carbonate environment into geothermal energy extraction wells was part of the project goals. The importance of this work was to affect the three factors limiting the expansion of geothermal development: distribution, field size and accompanying resource availability, and cost. Historically, power production from geothermal energy has been relegated to shallow heat plumes near active volcanic or geyser activity, or in areas where volcanic rocks still retain heat from their formation.
Thus geothermal development is spatially variable and site specific. Additionally, existing geothermal fields are only a few 10’s of square km in size, controlled by the extent of the heat plume and the availability of water for heat movement. This plume radiates heat both vertically as well as laterally into the enclosing country rock. Heat withdrawal at too rapid a rate eventually results in a decrease in electrical power generation as the thermal energy is “mined”. The depletion rate of subsurface heat directly controls the lifetime of geothermal energy production. Finally, the cost of developing deep (greater than 4 km) reservoirs of geothermal energy is perceived as being too costly to justify corporate investment.
Thus further development opportunities for geothermal resources have been hindered. To increase the effective regional implementation of geothermal resources as an energy source for power production requires meeting several objectives. These include: 1) Expand (oil and gas as well as geothermal) industry awareness of an untapped source of geothermal energy within deep permeable strata of sedimentary basins; 2) Identify and target specific geographic areas within sedimentary basins where deeper heat sources can be developed; 3) Increase future geothermal field size from 10 km2 to many 100’s km2 or greater; and 4) Increase the productive depth range for economic geothermal energy extraction below the current 4 km limit by converting deep depleted and abandoned gas wells and fields into geothermal energy extraction wells.
The first year of the proposed 3-year resource assessment covered an eight county region within the Delaware and Val Verde Basins of West Texas. This project has developed databases in Excel spreadsheet form that list over 8,000 temperature-depth recordings. These recordings come from header information listed on electric well logs recordings from various shallow to deep wells that were drilled for oil and gas exploration and production. The temperature-depth data is uncorrected and thus provides the lower temperature that is be expected to be encountered within the formation associated with the temperature-depth recording.
Numerous graphs were developed from the data, all of which suggest that a log-normal solution for the thermal gradient is more descriptive of the data than a linear solution. A discussion of these plots and equations are presented within the narrative.
Data was acquired that enable the determination of brine salinity versus brine density with the Permian Basin. A discussion on possible limestone and dolostone thermal conductivity parameters is presented with the purpose of assisting in determining heat flow and reservoir heat content for energy extraction. Subsurface maps of temperature either at a constant depth or within a target geothermal reservoir are discussed, but have yet to be completed. The Tucumcari basin of east-central New Mexico is a structural depression that existed as a depositional basin from Strawn (Middle Pennsylvanian) until late Wolfcampian (Early Permian) time. Depth to Precambrian ranges from 6500 ft to more than 9000 ft. High-angle faults form the north, east, and west edges of the basin.
No major structural discontinuities separate the basin from a shallow shelf to the south. Faults cut Pennsylvanian and Wolfcampain strata but generally do not offset post-Wolfcampian strata. Faults and regional structure control facies and thickness patterns within the Pennsylvanian and Wolfcampian. Coarse arkosic sands in the Pennsylvanian and Wolfcampian are good reservoirs. Those sands were deposited in northern and western parts of the basin and were derived from highlands of Precambrian granitic rocks that formed the northern and western margins of the basin. High-energy limestones are possible reservoirs in the southern part of the basin.
Porous Wolfcampian dolostones cover the Frio uplift on the east side of the basin. Pennsylvanian and Wolfcampian marine shales and micritic limestones are source rocks within the Tucumcari basin. Post-Wolfcampian strata are thermally immature.
Two presently noncommercial pools of oil and gas, the Latigo Ranch pool and the T-4 Ranch pool, have been discovered in Strawn sands in the northern part of the Tucumcari basin. Oil generated in the upper Paleozoic has migrated vertically into the Triassic; two oil accumulations, the Santa Rosa tar sands and the Newkirk oil pool, are in Triassic sandstones and have combined reserves of 153 million bbls of oil. Anomalously pressured gas (APG) assets, typically called 'basin-center' gas accumulations, represent either an underdeveloped or undeveloped energy resource in the Rocky Mountain Laramide Basins (RMLB). Historically, the exploitation of these gas resources has proven to be very difficult and costly. In this topical report, an improved exploration strategy is outlined in conjunction with a more detailed description of new diagnostic techniques that more efficiently detect anomalously pressured, gas-charged domains. The ability to delineate gas-charged domains occurring below a regional velocity inversion surface allows operators to significantly reduce risk in the search for APG resources.
The Wind River Basin was chosen for this demonstration because of the convergence of public data availability (i.e., thousands of mud logs and DSTs and 2400 mi of 2-D seismic lines); the evolution of new diagnostic techniques; a 175 digital sonic log suite; a regional stratigraphic framework; and corporate interest. In the exploration scheme discussed in this topical report, the basinwide gas distribution is determined in the following steps: (1) A detailed velocity model is established from sonic logs, 2-D seismic lines, and, if available, 3-D seismic data. In constructing the seismic interval velocity field, automatic picking technology using continuous, statistically-derived interval velocity selection, as well as conventional graphical interactive methodologies are utilized. (2) Next, the ideal regional velocity/depth function is removed from the observed sonic or seismic velocity/depth profile. The constructed ideal regional velocity/depth function is the velocity/depth trend resulting from the progressive burial of a rock/fluid system of constant rock/fluid composition, with all other factors remaining constant.
(3) The removal of the ideal regional velocity/depth function isolates the anomalously slow velocities and allows the evaluation of (a) the regional velocity inversion surface (i.e., pressure surface boundary); (b) detection and delineation of gas-charged domains beneath the velocity inversion surface (i.e., volumes characterized by anomalously slow velocities); and (c) variations within the internal fabric of the velocity anomaly (i.e., variations in gas charge). Using these procedures, it is possible to construct an anomalous velocity profile for an area, or in the case of the Wind River Basin, an anomalous velocity volume for the whole basin. Such an anomalous velocity volume has been constructed for the Wind River Basin based on 1600 mi of 2-D seismic data and 175 sonic logs, for a total of 132,000 velocity/depth profiles. The technology was tested by constructing six cross sections through the anomalous velocity volume coincident with known gas fields. In each of the cross sections, a strong and intense anomalously slow velocity domain coincided with the gas productive rock/fluid interval; there were no exceptions.
To illustrate the applicability of the technology, six target areas were chosen from a series of cross sections through the anomalous velocity volume. The criteria for selection of these undrilled target areas were (1) they were characterized by anomalous velocity domains comparable to known gas fields; (2) they had structural, stratigraphic, and temporal elements analogous to one of the known fields; and (3) they were located at least six sonic miles from the nearest known gas field. The next step in the exploration evolution would be to determine if the detected gas-charged domains are intersected by reservoir intervals characterized by enhanced porosity and permeability. If, in any of these targeted areas, the gas-charged domains are penetrated by reservoir intervals with enhanced storage and deliverability, the gas-charged domains could be elevated to drillable prospects. Hopefully, the work described in this report (the detection and delineation of gas-charged domains) will enable operators in the Wind River Basin and elsewhere to reduce risk significantly and increase the rate and magnitude of converting APG resources to energy reserves.
This project will provide a full demonstration of an entirely new package of exploration technologies that will result in the discovery and development of significant new gas reserves now trapped in unconventional low-permeability reservoirs. This demonstration includes the field application of these technologies, prospect definition and well siting, and a test of this new strategy through wildcat drilling.
In addition this project includes a demonstration of a new stimulation technology that will improve completion success in these unconventional low permeability reservoirs which are sensitive to drilling and completion damage. The work includes two test wells to be drilled by Snyder Oil Company on the Shoshone/Arapahoe Tribal Lands in the Wind River Basin.
Mks Toolkit - Interoperability V9.0 5u Win Me/nt/2000/xp/2003 Cromwell
This basin is a foreland basin whose petroleum systems include Paleozoic and Cretaceous source beds and reservoirs which were buried, folded by Laramide compressional folding, and subsequently uplifted asymmetrically. The anomalous pressure boundary is also asymmetric, following differential uplift trends. The Institute for Energy Research has taken a unique approach to building a new exploration strategy for low-permeability gas accumulations in basins characterized by anomalously pressured, compartmentalized gas accumulations.
Key to this approach is the determination and three-dimensional evaluation of the pressure boundary between normal and anomalous pressure regimes, and the detection and delineation of areas of enhanced storage capacity and deliverability below this boundary. In response to the Geothermal Energy Research, Development, and Demonstration Act of 1974, a federal geothermal program has been established with the objective of stimulating the commercial development of geothermal resources. The program goal is to increase the annual rate of energy utilization from the present 0.04 quads (500 MWe) to 0.3 to 0.5 quads in the near-term (about 1985), 4.0 to 9.0 quads in the mid-term (1985 to 2000), and 16.0 to 28.0 quads in the long-term (by about 2020). The realization of these goals depends upon the discovery and exploitation of many new geothermal resource areas.
The Department of Energy program for geothermal exploration and assessment has been structured to address technological barriers presently hindering the economical discovery and delineation of geothermal resources. The program elements - exploration technology, reservoir assessment, reservoir confirmation, and reservoir engineering - are described in light of the need to evaluate some 1500 new prospects in order to meet the federal midterm electric power goal of 20,000 MWe on line by the year 2000.
The program elements are illustrated with suggested sequences from exploration, assessment, and confirmation of a 200-MWe resource in the eastern Basin and Range physiographic province. The estimated costs for these sequences are $385,000, $565,000, and $3,190,000, respectively. Deep drilling constitutes the major element in the confirmation costs.
MKS Toolkit 8.1 Release NotesFebruary 2002MKS is the leading provider of Windowsautomation tools for system administration anddevelopment in a pure Windows or mixed UNIX/Linuxand Windows environment.MKS Inc.12701 Fair Lakes Circle, Suite 350Fairfax VA USAMain:+1-703-803-3343Support:+1-703-803-7660MKS Toolkit™ Release NotesVersion 8.1May 2002MKS Toolkit 8.1In addition to being a maintenance release for MKS Toolkit 8.0,MKS Toolkit 8.1 contains many enhancements that we think you willfind useful. The enhancements fall largely into the followingcategories: major improvements to our extensive suite ofconnectivity utilities, improved monitors in AlertCentre,significant modifications to our Web and HTML utilities,ongoing support for new releases of Windows and Visual Studio,and ongoing enhancements to improve usability of MKS Toolkit.The section discussesthe problems resolved in this release. The following sectiondiscusses the specific enhancements in much greater detail.Improvements to Connectivity Suite.
Upgraded Secure Shell.We have upgraded our secure shell to the latest version,which fixes many bugs. In addition, we have made severalother customer-requested enhancements to secure shell. Note:it is not currently possible to adequately secure key files andother data, if you install the secure shell server( secshd) onto a FAT file system. Therefore, we donot support use of the server on such a file system;however, the secure clients are all still usable in this case. Configuration of Connectivity Utilities.All configurable connectivity utilities (secure shell,remote utilities, and telnet) are now configurable from theMKS Toolkit control panel applet. We have provided contexthelp for all configuration items.
Easier Launch of Connectivity Utilities.There are now Startmenu entries to connect to a remote machine using thesecure shell, remote login, and xterm.All Connectivity Utility menu entries are now groupedonto a single submenu. New Cryptography Utility.We have added the openssl utility to let youperform various cryptography functions. This utility isuseful for creating a variety of keys and certificates,and for understanding the origin and validity of keysand certificates acquired from other sources. Usingopenssl, you can set up certificates and keysso others can securely access your servers usingSSL-protected protocols such as HTTPS and those inMKS secure shell. You can also use it to handle signedor encrypted mail, and you can even use it as a serveror client for sending and receiving encrypted informationusing those certificates and keys. This is especiallyuseful in testing that secure connections are workingcorrectly.
Connectivity Solutions Guide.MKS Toolkit 8.1 contains the first version of this newguide discussing our suite of connectivity tools and howto solve problems with them.