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1

Tests pits for calibrating well logging equipment in fractured hard-rock environment  

SciTech Connect

The calibration facility consists of three pits containing fine-grained granite, coarse-grained granite, and medium-grained metamorphosed granodiorite. Each pit contains large quarried blocks of rock that are 8 ft octagons and form a 20 ft stack. The blocks are saturated with water and sealed in watertight fiberglass containers that are recessed so that the top of the upper block is approximately level with the ground. The blocks contain simulated fractures that are formed by the joints between the blocks and by saw cuts at several locations. Cored boreholes through the blocks are 7 7/8 in. in diameter, with a fiberglass-cased ''rat hole'' extending 30 ft below the bottom block. Laboratory and well logging studies (United States Geological Society, Schlumberger, and Dresser Atlas logs) have been made to determine the physical properties of rocks in the three pits, and preliminary results are reported. Porosities of individual samples (core measurements) taken at 1 ft intervals in the three pits range from 0.00 to 0.90%, densities from 2.64 to 2.79 g/cm/sup 3/, and sonic velocities from 18,700 to 22,500 ft/sec. Radio-element of individual samples (core measurements) taken at 5 ft intervals from these test pits range from 0.62 to 4.08% K (potassium) content, from 0.34 to 5.01 ppM RaeU (uranium) content and from 0.46 to 19.6 ppM Th (thorium) content. Access to the pits for calibrating well logging equipment can be arranged by contacting the United States Geological Survey (phone number 303-236-5913) in Denver, Colorado. 4 refs., 38 figs., 4 tabs.

Mathews, M.A.; Scott, J.H.; LaDelfe, C.M.

1985-01-01

2

Well-logging activities in Russia  

SciTech Connect

The report is a brief survey of the current state of well-logging service in Russia (number and types of crews, structure of well-logging jobs, types of techniques used, well-logging equipment, auxiliary downhole jobs, etc.). Types and peculiarities of well data acquisition and processing hardware and software are discussed (petrophysics included). New well-logging technologies used in Russia (new methods of electric logging data processing, electromagnetic logging, pulse neutron logging, nuclear magnetic resonance logging, acoustic tomography, logging-testing-logging technique, etc.) are surveyed. Comparison of the Tengiz field (Kazakhstan) well data obtained by Schlumberger and Neftegazgeofizika Association crews is given. Several problems and drawbacks in equipment and technology used by well-logging crews in Russia are discussed.

Savostyanov, N.A. (Neftegazgeofizika, Moscow (Russian Federation))

1993-09-01

3

Well logging II - Electric and acoustic logging  

SciTech Connect

This book covers electric logging, log interpretation and electromagnetic principles. The book also discuss principles of acoustic logging and details of acoustic log interpretation, including effects of amplitude attenuation devices and investigation of interval transit times.

Jorden, J.R.; Campbell, F.L.

1986-01-01

4

Chemical logging of geothermal wells  

DOEpatents

The presence of geothermal aquifers can be detected while drilling in geothermal formations by maintaining a chemical log of the ratio of the concentrations of calcium to carbonate and bicarbonate ions in the return drilling fluid. A continuous increase in the ratio of the concentrations of calcium to carbonate and bicarbonate ions is indicative of the existence of a warm or hot geothermal aquifer at some increased depth.

Allen, Charles A. (Idaho Falls, ID); McAtee, Richard E. (Idaho Falls, ID)

1981-01-01

5

21 CFR 211.182 - Equipment cleaning and use log.  

Code of Federal Regulations, 2013 CFR

...lubrication and adjustments), and use shall be included in individual equipment logs that show the date, time, product, and lot...indicating that the work was performed. Entries in the log shall be in chronological order. [73 FR 51933,...

2013-04-01

6

Well logging evaporative thermal protection system  

SciTech Connect

An evaporative thermal protection system for use in hostile environment well logging applications, the system including a downhole thermal protection cartridge disposed within a well logging sonde or tool to keep a payload such as sensors and support electronics cool, the cartridge carrying either an active evaporative system for refrigeration or a passive evaporative system, both exhausting to the surface through an armored flexible fluidic communication mechanical cable.

Lamers, M.D.; Martelli, V.P.

1981-02-03

7

Sedimentological analysis using geophysical well logs  

SciTech Connect

The application of geophysical well logs in sedimentology and stratigraphic prospecting holds great promise in solving a number of geological problems. A suite of logs provides data on a wide range of rock properties: vertical and lateral variation of resistivity, natural polarization, natural and induced radioactivity, shear strength, and acoustic properties. Each of these properties is controlled by the depositional environment of the sediments and their later diagenesis. The attention of geologists and geophysicists is drawn to new techniques in the interpretation of geophysical well logs for exploration, appraisal, and development of oil and gas fields. The relationship between geophysical logs and depositional environments is explored. Bulk composition, rock structure, and texture and facies variation can be quantified by electric log parameters. Also, the possibility of using logs to demonstrate long- and short-period sedimentary cycles is demonstrated. Methods of sedimentological analysis using geophysical well logs are demonstrated. The importance of a genetic approach in the interpretation of geological sequences and paleogeological reconstructions is emphasized using examples taken from oil and gas prospecting operations in the Ukraine.

Izotova, T.S. (Ukrainian State Geological Research Institute, Kiev (Ukraine))

1993-09-01

8

Well logging for the nontechnical person  

SciTech Connect

The contents of this book are: Introduction to logging; Reading logs; Formation parameters; Mud logging; Resistivity measurements; Porosity measurements; Putting it all together; detailed interpretations; Computer-generated logs; Specialty logs.

Johnson, D.E.; Pile, K.E.

1988-01-01

9

Unconventional neutron sources for oil well logging  

NASA Astrophysics Data System (ADS)

Americium-Beryllium (AmBe) radiological neutron sources have been widely used in the petroleum industry for well logging purposes. There is strong desire on the part of various governmental and regulatory bodies to find alternate sources due to the high activity and small size of AmBe sources. Other neutron sources are available, both radiological (252Cf) and electronic accelerator driven (D-D and D-T). All of these, however, have substantially different neutron energy spectra from AmBe and thus cause significantly different responses in well logging tools. We report on simulations performed using unconventional sources and techniques to attempt to better replicate the porosity and carbon/oxygen ratio responses a well logging tool would see from AmBe neutrons. The AmBe response of these two types of tools is compared to the response from 252Cf, D-D, D-T, filtered D-T, and T-T sources.

Frankle, C. M.; Dale, G. E.

2013-09-01

10

Well log evaluation of gas hydrate saturations  

USGS Publications Warehouse

The amount of gas sequestered in gas hydrates is probably enormous, but estimates are highly speculative due to the lack of previous quantitative studies. Gas volumes that may be attributed to a gas hydrate accumulation within a given geologic setting are dependent on a number of reservoir parameters; one of which, gas-hydrate saturation, can be assessed with data obtained from downhole well logging devices. The primary objective of this study was to develop quantitative well-log evaluation techniques which will permit the calculation of gas-hydrate saturations in gas-hydrate-bearing sedimentary units. The "standard" and "quick look" Archie relations (resistivity log data) yielded accurate gas-hydrate and free-gas saturations within all of the gas hydrate accumulations assessed in the field verification phase of the study. Compressional wave acoustic log data have been used along with the Timur, modified Wood, and the Lee weighted average acoustic equations to calculate accurate gas-hydrate saturations in all of the gas hydrate accumulations assessed in this study. The well log derived gas-hydrate saturations calculated in the field verification phase of this study, which range from as low as 2% to as high as 97%, confirm that gas hydrates represent a potentially important source of natural gas.

Collett, T. S.

1998-01-01

11

Well log evaluation of gas hydrate saturations  

USGS Publications Warehouse

The amount of gas sequestered in gas hydrates is probably enormous, but estimates are highly speculative due to the lack of previous quantitative studies. Gas volumes that may be attributed to a gas hydrate accumulation within a given geologic setting are dependent on a number of reservoir parameters; one of which, gas-hydrate saturation, can be assessed with data obtained from downhole well logging devices. The primary objective of this study was to develop quantitative well-log evaluation techniques which will permit the calculation of gas-hydrate saturations in gas-hydrate-bearing sedimentary units. The `standard' and `quick look' Archie relations (resistivity log data) yielded accurate gas-hydrate and free-gas saturations within all of the gas hydrate accumulations assessed in the field verification phase of the study. Compressional wave acoustic log data have been used along with the Timur, modified Wood, and the Lee weighted average acoustic equations to calculate accurate gas-hydrate saturations in this study. The well log derived gas-hydrate saturations calculated in the field verification phase of this study, which range from as low as 2% to as high as 97%, confirm that gas hydrates represent a potentially important source of natural gas.

Collett, Timothy, S.

1998-01-01

12

Subsurface sequence stratigraphic correlation using well logs  

NSDL National Science Digital Library

Students are given hard copies of a subsurface section containing gamma and resistivity logs of nine closely-spaced (well distance varies from 1 to 3 km) wells from Delaware Basin, southeast New Mexico for an interval of ~ 200 m clastic succession of Morrow sandstone of Pennsylvanian age. Core sedimentology of one of these wells is also provided. Students' task is to correlate the well logs to generate a stratigraphic cross-section of the area using sequence stratigraphic approach. As the data are from Delaware Basin, southeast New Mexico, student should first gather the knowledge of regional setting of the basin, with a particular emphasis to the paleo-eustasy. (Clue: in Delaware Basin, Morrow sandstones deposited in a low accommodation settings with high-amplitude fluctuations of sea-level.) When correlating the well logs students should start with the well which has lithological information. Students should try to correlate the mudstones first. The two most prominent sequence stratigraphic surfaces with comparatively higher correlation-length are 'sequence boundary' produced by pronounced fall of sea-level, and 'maximum flooding surface' generated at the time of highest stand of sea-level. Students should pay particular attention to incised-valley-fill deposits. After completing the correlation, students should check whether their correlation satisfy our prevailing ideas of sequence stratigraphy and stratal packaging. Student should prepare a brief description of overall depositional environments and sea-level history of the area substantiating their subsurface correlation. By doing this exercise, students will learn how to apply sequence stratigraphic principles in interpreting subsurface data, particularly from well logs.

Gani, M. R.

13

Automatic determination of lithology from well logs  

SciTech Connect

A procedure combining modern wireline measurements with a lithofacies data base has been developed to produce an automatic lithologic description of the formations crossed by a well. The database lithofacies are defined from petrographic knowledge and translated in terms of log responses. The assignment of depth levels to a lithofacies is done with the data base and with a discriminating function (Bayesian decision rule). External knowledge can be taken into account by use of artificial intelligence methods. A confidence factor is produced for each result. Logs currently in the data base are the density, neutron, sonic transit time, gamma ray, photoelectric cross section, and concentrations of thorium, potassium, and uranium. Major lithofacies groups represented in the data base include sandstones, limestones, dolomites, shales, coals, and evaporites. These are subdivided by introducing cement and special minerals and by considering porosity ranges. The construction of the data base is a critical step. It is largely empirical and requires careful calibration against intervals with well-known lithologies (e.g., from cores). The data base can be tuned to local conditions. The procedure has been tested in several environments and compared with cores and mud log descriptions. A detailed lithologic column can be produced at the wellsite and used in decision making. The results can also serve as input for further geologic studies of facies and sequences or for quantitative evaluation of formations.

Delfiner, P.C.; Peyret, O.; Serra, O.

1987-09-01

14

Derive capillary pressure from well logs  

SciTech Connect

A new approach has been developed to estimate in-situ capillary pressure and relative permeability characteristics in the transition zone. The technique is based on incorporating petrophysical data measured on core samples with well log analysis. Relative permeability can be determined for both drainage and inhibition conditions using the matched capillary pressure data. A technique has been developed to extrapolate petro-physical data where core data is absent or not representative of in-situ conditions. It is based on using log data to derive a water saturation vs. depth profile in the transition zone of the formation of interest. The log-derived water saturation distribution is then correlated to generalized capillary pressure curves typical of the formation studied. The capillary pressure type curves are generated from available core data and other petrophysical information. Relative permeability curves are then generated using correlations based on Purcell's model. The technique can be used in multi-layered and homogeneous reservoirs provided that one homogeneous layer is at least 20 ft thick.

Ibrahim, A. (Suez Canal Univ. (Egypt)); Desbrandes, R.; Bassiouni, Z. (Louisiana State Univ., Baton Rouge, LA (United States))

1994-07-01

15

Method of making well logging apparatus  

Microsoft Academic Search

A replaceable insulating sleeve is disposed around the lower end of a drill string used in drilling a well. The sleeve is restrained from rotating relative to the drill string, but can be released and quickly slipped off the drill string in the field to permit rapid replacement if damaged, or if alternate equipment is required. The sleeve carries sensing

J. D. Jeter; H. S. More

1982-01-01

16

Sonic well logging tool longitudinal wave attenuator  

SciTech Connect

This patent describes an attenuator for use with a well logging tool in attenuating a wave propagating longitudinally along the tool when the tool is disposed in a borehole of an oil well. It comprises: a plurality of layers of a first material. The first material including metal washers; a plurality of layers of a second material interleaved with the plurality of layers of the first material. The second material including rubber-like washers; and an inner member. The interleaved rubber-like washers and metal washers being wrapped around the inner member. The inner member including an outwardly directed flange on which one end of the interleaved rubber-like washers and metal washers rest.

Wignall, A.H.; Hoyle, D.C.

1989-10-10

17

High resolution gamma spectroscopy well logging system.  

National Technical Information Service (NTIS)

A Gamma Spectroscopy Logging System (GSLS) has been developed to study sub-surface radionuclide contamination. The absolute counting efficiencies of the GSLS detectors were determined using cylindrical reference sources. More complex borehole geometries w...

J. R. Giles K. J. Dooley

1997-01-01

18

GAMMA-RAY SPECTROSCOPY IN WELL LOGGING  

Microsoft Academic Search

Thermal neutron capture gamma rays have been observed in boreholes ; drilled in shales, sandstones, and limestones. A capsuled source of neutrons and ; a scintillation crystal detector, connected through 5,000 ft of logging cable to ; a transistorized, multichannel, pulse-height analyzer, were used. Resolved peaks ; were identified on the basis of the known energies of expected gamma rays

Richard L. Caldwell; W. F. Baldwin; J. D. Bargainer; J. E. Berry; G. N. Salaita; R. W. Sloan

1963-01-01

19

Method and apparatus for logging earth boreholes. [in deviated wells  

Microsoft Academic Search

A self-contained, battery powered well logging instrument is pumped down the interior of a drill pipe string having a catcher sub at its lower end. When the logging instrument latches into the catcher sub, the pumped fluid circulation is blocked, after which increased pump pressure switches a valve assembly to recreate circulation and energize the logging instrument to the standby

Angehrn

1977-01-01

20

36 CFR 1254.12 - Will NARA log or inspect my computer, other equipment, and notes?  

Code of Federal Regulations, 2013 CFR

... true Will NARA log or inspect my computer, other equipment, and notes? 1254...12 Will NARA log or inspect my computer, other equipment, and notes? (a) If you bring personal computers, scanners, tape recorders,...

2013-07-01

21

A borehole corrected pulsed neutron well logging system  

Microsoft Academic Search

An improved well logging method has been developed for more accurately measuring the neutron capture cross section (Sigma) of earth formations. A measurement of Sigma with depth (well log) is useful in estimating hydrocarbon saturation of saline reservoirs. Gamma rays are detected following each burst of neutrons emitted by a pulsed 14 MeV neutron generator. An iterative procedure was developed

W. E. Schultz; H. D. Smith; J. L. Verbout; J. R. Bridges; G. H. Garcia

1985-01-01

22

Multiscale and Wavelet Transform with Applications in Well LOG Analysis.  

National Technical Information Service (NTIS)

Theoretical concepts and applications of the multiscale transform and the wavelet transform are discussed with attention given to well logs. A well log is a sequence of measures obtained from a borehole and a record of the variation in lithology. As part ...

P. L. Vermeer

1992-01-01

23

Needs of well logging industry in new nuclear detectors  

Microsoft Academic Search

In this paper we discuss some challenges of nuclear well logging related to the lack of the gamma ray and neutron detection technologies capable of operating reliably in the down-hole hostile environment. Different nuclear well logging techniques are described, the parameters of nuclear detectors which would satisfy the requirements imposed by these techniques are considered, and the results of the

Anton Nikitin; Steven Bliven

2010-01-01

24

Geothermal Well Log Interpretation State of the Art. Final Report.  

National Technical Information Service (NTIS)

An in-depth study of the state of the art in Geothermal Well Log Interpretation has been made encompassing case histories, technical papers, computerized literature searches, and actual processing of geothermal wells from New Mexico, Idaho, and California...

S. K. Sanyal L. E. Wells R. E. Bickham

1980-01-01

25

Geothermal well log interpretation state of the art. Final report  

SciTech Connect

An in-depth study of the state of the art in Geothermal Well Log Interpretation has been made encompassing case histories, technical papers, computerized literature searches, and actual processing of geothermal wells from New Mexico, Idaho, and California. A classification scheme of geothermal reservoir types was defined which distinguishes fluid phase and temperature, lithology, geologic province, pore geometry, salinity, and fluid chemistry. Major deficiencies of Geothermal Well Log Interpretation are defined and discussed with recommendations of possible solutions or research for solutions. The Geothermal Well Log Interpretation study and report has concentrated primarily on Western US reservoirs. Geopressured geothermal reservoirs are not considered.

Sanyal, S.K.; Wells, L.E.; Bickham, R.E.

1980-01-01

26

Method and apparatus for gamma ray well logging  

Microsoft Academic Search

A radioactive logging source carried by a logging tool injects gamma rays into the formation. A detector generates a pulse for each gamma ray incident upon the detector having an amplitude proportional to the gamma ray energy. Electrical signals corresponding to each such amplitude are delivered to the surface. These incident gamma rays originate from the formation as well as

Hubner

1985-01-01

27

Estimating thermal conductivity from core and well log data  

NASA Astrophysics Data System (ADS)

The aim of the presented work was to introduce a method of estimating thermal conductivity using well log data. Many petrophysical properties of rocks can be determined both by laboratory measurements and well-logs. It is thus possible to apply geophysical data to empirical models based on relationships between laboratory measured parameters and derive continuous thermal conductivity values in well profiles. Laboratory measurements were conducted on 62 core samples of Meso-Paleozoic rocks from the Carpathian Foredeep. Mathematical models were derived using multiple regression and neural network methods. Geophysical data from a set of seven well logs: density, sonic, neutron, gamma ray, spectral gamma ray, caliper and resistivity were applied to the obtained models. Continuous thermal conductivity values were derived in three well profiles. Analysis of the obtained results shows good consistence between laboratory data and values predicted from well log data.

G?sior, Irena; Przelaskowska, Anna

2014-08-01

28

Estimating thermal conductivity from core and well log data  

NASA Astrophysics Data System (ADS)

The aim of the presented work was to introduce a method of estimating thermal conductivity using well log data. Many petrophysical properties of rocks can be determined both by laboratory measurements and well-logs. It is thus possible to apply geophysical data to empirical models based on relationships between laboratory measured parameters and derive continuous thermal conductivity values in well profiles. Laboratory measurements were conducted on 62 core samples of Meso-Paleozoic rocks from the Carpathian Foredeep. Mathematical models were derived using multiple regression and neural network methods. Geophysical data from a set of seven well logs: density, sonic, neutron, gamma ray, spectral gamma ray, caliper and resistivity were applied to the obtained models. Continuous thermal conductivity values were derived in three well profiles. Analysis of the obtained results shows good consistence between laboratory data and values predicted from well log data.

G?sior, Irena; Przelaskowska, Anna

2014-04-01

29

Fluid-temperature logs for selected wells in eastern Washington  

SciTech Connect

This Open-File Report consists of fluid temperature logs compiled during studies of the geohydrology and low temperature geothermal resources of eastern Washington. The fluid temperature logs are divided into two groups. Part A consists of wells which are concentrated in the Moses Lake-Ritzville-Connell area. Full geophysical log suites for many of these wells are presented in Stoffel and Widness (1983) and discussed in Widness (1983, 1984). Part B consists of wells outside of the Moses Lake-Ritzville-Connell study area.

Stoffel, K.L.; Widness, S. (comps.)

1983-12-01

30

Fluid-Rock Characterization and Interactions in NMR Well Logging  

SciTech Connect

The objective of this project was to characterize the fluid properties and fluid-rock interactions which are needed for formation evaluation by NMR well logging. NMR well logging is finding wide use in formation evaluation. The formation parameters commonly estimated were porosity, permeability, and capillary bound water. Special cases include estimation of oil viscosity, residual oil saturation, location of oil/water contact, and interpretation on whether the hydrocarbon is oil or gas.

Hirasaki, George J.; Mohanty, Kishore K.

2003-02-10

31

Logging while drilling keeps horizontal well on small target  

Microsoft Academic Search

This paper reports that the logging-while-drilling (LWD) measurement to two resistivities of different characteristics had led to a new interpretation method for the analysis of horizontal wells. By logging deep and shallow resistivity in real-time, marker beds were identified to help maintain well bore trajectory. The resistivity measurements were split into vertical and horizontal components to provide additional information of

J. Leake; F. Shray

1991-01-01

32

Fluid-Rock Characterization and Interactions in NMR Well Logging  

SciTech Connect

The objective of this project was to characterize the fluid properties and fluid-rock interactions that are needed for formation evaluation by NMR well logging. The advances made in the understanding of NMR fluid properties are summarized in a chapter written for an AAPG book on NMR well logging. This includes live oils, viscous oils, natural gas mixtures, and the relation between relaxation time and diffusivity.

Hirasaki, George J.; Mohanty, Kishore K.

2003-02-10

33

Determination of lithology from well logs using a neural network  

SciTech Connect

The authors have developed a computer program to automatically determine lithologies from well logs using a back-propagation neural network. Unlike a conventional serial computer, a neural network is a computational system composed of nodes (sometimes called neurons, neurodes, or units) and the connections between these nodes. Neural computing attempts to emulate the functions of the mammalian brain, thus mimicking thought processes. The neural network approach differs from previous pattern recognition methods in its ability to learn from examples. Unlike conventional statistical methods, this new approach does not require sophisticated mathematics and a large amount of statistical data. This paper discusses the application of neural networks to a pattern recognition problem in geology: the determination of lithology from well logs. The neural network determined the lithologies (limestone, dolomite, sandstone, shale, sandy and dolomitic limestones, sandy dolomite, and shale sandstone) from selected well logs in a fraction of the time required by an experienced human log analyst.

Rogers, S.J.; Fang, J.H. (Univ. of Alabama, Tuscaloosa (United States)); Karr, C.L.; Stanley, D.A. (Bureau of Mines, Tuscaloosa, AL (United States))

1992-05-01

34

Heuristic search method for optimal zonation of well logs  

SciTech Connect

Optimal zonation of well-log data, that is, determining an optimal number of major segments such as waveforms in a log, may be achieved by employing a criterion of minimum variance (within a segment) and a heuristic search of potential boundary (link) points of digitized log data. This new method is based on an algorithm originally devised by D.M. Hawkins and D.F. Merriam in 1973. Their method can be improved by introducing a heuristic search procedure, thereby decreasing computer time by 7- to 50-fold, depending on the number of data points and configuration of the logs. Time saving is proportional to the size of the data set. Three examples - one hypothetical and two real-are used to illustrate the modification of the Hawkins and Merriam algorithm.

Chen, H.C.; Fang, J.H.

1986-07-01

35

User's manual for geophysical well-logging software programs  

SciTech Connect

Since 1958 the Ground-Water Surveillance Program for the Hanford Site has made geophysical logging measurements in most of the 800 wells and deep boreholes that have been drilled on the Hanford Site. In 1980 the Pacific Northwest Laboratory (PNL), which conducts the Ground-Water Surveillance Program, began forming a computerized data base for storing and retrieving geophysical well log data and developing software for quantitative analysis of the well log data. This report, designed to serve as a user's guide, documents the data base system that handles the well log data. Two programs, DIGLOG1 and LOGIT, are used to manipulate the data. The program DIGLOG1 translates analog paper strip charts into digital format; the program LOGIT is a general utility program that edits, displays, checks, stores, writes, and deletes sets of well log data. These two programs do not provide sophisticated display and analytical capabilities; rather, they provide programs that give the user easy access to powerful standard analytical software.

Petrie, G.M.; Gibson, D.; Blair, S.C.

1983-02-01

36

Improved simulation for interpreting temperature logs in water injection wells  

Microsoft Academic Search

An improved simulation for temperature logs (TL) in water injection wells, is described. Improvements, based on the reduction of assumptions used by previous investigators, are demonstrated by comparison of field data and simulator results showing excellent agreement of TL profiles over the entire well depth. The utility of short period hot water injection just preceding shut-in, as an injection profile

J. Fagley; H. S. Fogler; C. B. Davenport; R. S. Millhone

1981-01-01

37

Wireline well logging an underutilized technique in reservoir evaluation  

SciTech Connect

Wireline well logs have three general uses in geothermal exploration and reservoir evaluation: reservoir parameter analysis, lithologic column determination, and reservoir size resolution. Reservoir flow testing data are acquired to understand the flow rate, life, and production potential of the geothermal reservoir. These data are a coarse subsurface measurement of the geothermal prospect. Wireline logs acquired from wells in a geothermal prospect are used to define in detail, or estimate the reservoir parameters of temperature, thickness, lateral size, amount of fracture and intergranular pore space, and the quantity and quality of fluid that might be produced. Laboratory measurements can be made on core samples and drill cuttings samples to define the intrinsic behavior of the materials and fluid that compose the geotheraml reservoir. Wireline log measurements are needed to correlate and link the reservoir testing and core analysis, reduce the amount of time needed for flow testing, and predict the production life (amount of heat and fluid available) in a geothermal field.

Mathews, M.

1981-01-01

38

Store well-logging data with ObjectStore ODBMS  

NASA Astrophysics Data System (ADS)

How to store well-logging data in a database is a problem encountered by developers of exploration software. A method to store these data with an ODBMS is presented; C+ + is the programming language and ObjectStore the database system. This method is applied to the development of GRIstation—a joint project between GRI China and STS USA.

Li, Haifei

1995-12-01

39

Fluid-Rock Characterization and Interactions in NMR Well Logging  

SciTech Connect

The objective of this report is to characterize the fluid properties and fluid-rock interactions that are needed for formation evaluation by NMR well logging. The advances made in the understanding of NMR fluid properties are summarized in a chapter written for an AAPG book on NMR well logging. This includes live oils, viscous oils, natural gas mixtures, and the relation between relaxation time and diffusivity. Oil based drilling fluids can have an adverse effect on NMR well logging if it alters the wettability of the formation. The effect of various surfactants on wettability and surface relaxivity are evaluated for silica sand. The relation between the relaxation time and diffusivity distinguishes the response of brine, oil, and gas in a NMR well log. A new NMR pulse sequence in the presence of a field gradient and a new inversion technique enables the T{sub 2} and diffusivity distributions to be displayed as a two-dimensional map. The objectives of pore morphology and rock characterization are to identify vug connectivity by using X-ray CT scan, and to improve NMR permeability correlation. Improved estimation of permeability from NMR response is possible by using estimated tortuosity as a parameter to interpolate between two existing permeability models.

George J. Hirasaki; Kishore K. Mohanty

2005-09-05

40

Logging while drilling keeps horizontal well on small target  

SciTech Connect

This paper reports that the logging-while-drilling (LWD) measurement to two resistivities of different characteristics had led to a new interpretation method for the analysis of horizontal wells. By logging deep and shallow resistivity in real-time, marker beds were identified to help maintain well bore trajectory. The resistivity measurements were split into vertical and horizontal components to provide additional information of formation evaluation. In 1945, Ark Fuel Co. discovered and began developing the Olla field on the crest of the La Salle arch in La Salle Parish, La. Oil production comes from the Wilcox formation from alluvial sand packages that range in thickness from 3 ft to 120 ft. Now operated by Oxy U.S.A. Inc., Olla field was chosen in 1990 for a horizontal well pilot project. It was hoped that a horizontal well could alleviate water coming in one of the field's more productive sand packages- the 40-ft Cruse sand.

Leake, J. (Oxy USA Inc., Houston, TX (US)); Shray, F. (Schlumberger Well Services, Midland, TX (United States))

1991-09-23

41

Automated Variance Reduction Applied to Nuclear Well-Logging Problems  

SciTech Connect

The Monte Carlo method enables detailed, explicit geometric, energy and angular representations, and hence is considered to be the most accurate method available for solving complex radiation transport problems. Because of its associated accuracy, the Monte Carlo method is widely used in the petroleum exploration industry to design, benchmark, and simulate nuclear well-logging tools. Nuclear well-logging tools, which contain neutron and/or gamma sources and two or more detectors, are placed in boreholes that contain water (and possibly other fluids) and that are typically surrounded by a formation (e.g., limestone, sandstone, calcites, or a combination). The response of the detectors to radiation returning from the surrounding formation is used to infer information about the material porosity, density, composition, and associated characteristics. Accurate computer simulation is a key aspect of this exploratory technique. However, because this technique involves calculating highly precise responses (at two or more detectors) based on radiation that has interacted with the surrounding formation, the transport simulations are computationally intensive, requiring significant use of variance reduction techniques, parallel computing, or both. Because of the challenging nature of these problems, nuclear well-logging problems have frequently been used to evaluate the effectiveness of variance reduction techniques (e.g., Refs. 1-4). The primary focus of these works has been on improving the computational efficiency associated with calculating the response at the most challenging detector location, which is typically the detector furthest from the source. Although the objective of nuclear well-logging simulations is to calculate the response at multiple detector locations, until recently none of the numerous variance reduction methods/techniques has been well-suited to simultaneous optimization of multiple detector (tally) regions. Therefore, a separate calculation is typically performed for each desired detector response. This paper summarizes recent work to apply and evaluate the effectiveness of deterministic-adjoint-based variance reduction methods, including a recently developed method for simultaneous optimization of multiple detectors, for two simple nuclear well-logging tool problems that have been widely used in the variance reduction literature. The computational effectiveness of the method for simultaneous optimization is also compared to the use of multiple, individually optimized simulations for these simple well-logging problems.

Wagner, John C [ORNL; Peplow, Douglas E. [ORNL; Evans, Thomas M [ORNL

2008-01-01

42

Prospect generation using digital well log data - Minnelusa formation  

SciTech Connect

Trapping in the Permian Minnelusa Formation is almost entirely stratigraphic. Much of the oil is trapped in buried hilltops controlled by the unconformity at the top of the Minnelusa. Highly localized stratigraphic changes within the upper Minnelusa are also important. The database used for computer mapping of the Minnelusa play includes cartographic data, formation and zone tops, and digital well log traces. Digital log data consist of sonic and gamma-ray curves from all but 300 of the 4100 wells penetrating the Minnelusa Formation. Using this data base, exploration geologists have been able to make any needed type or regional stratigraphic map in a few days. Many recent discoveries have been made on leads previously generated by computer maps.

Shier, D.E.

1985-05-01

43

Log curve amplitude slicing: Visualization of well log amplitudes for paleogeographic reconstruction of the Middle Devonian Traverse Group, Michigan Basin  

Microsoft Academic Search

Well log curve shapes and amplitude trends are routinely used to correlate and map formations and reservoirs across petroleum basins or fields. The methods typically employed for correlation and mapping fail, however, to make full use of the vertical resolution of well log curves. A new technique, log curve amplitude slicing (LCAS) facilitates correlation by generating a series of subhorizontal

Albert Sidney Wylie Jr.

2002-01-01

44

Instant well-log inversion with a parallel computer  

SciTech Connect

Well-log analysis requires several vectors of input data to be inverted with a physical model that produces more vectors of output data. The problem is inherently suited to either vectorization or parallelization. PLATO (parallel log analysis, timely output) is a research prototype system that uses a parallel architecture computer with memory-mapped graphics to invert vector data and display the result rapidly. By combining this high-performance computing and display system with a graphical user interface, the analyst can interact with the system in real time'' and can visualize the result of changing parameters on up to 1,000 levels of computed volumes and reconstructed logs. It is expected that such instant'' inversion will remove the main disadvantages frequently cited for simultaneous analysis methods, namely difficulty in assessing sensitivity to different parameters and slow output response. Although the prototype system uses highly specific features of a parallel processor, a subsequent version has been implemented on a conventional (Serial) workstation with less performance but adequate functionality to preserve the apparently instant response. PLATO demonstrates the feasibility of petroleum computing applications combining an intuitive graphical interface, high-performance computing of physical models, and real-time output graphics.

Kimminau, S.J.; Trivedi, H.

1993-08-01

45

Well logging apparatus and method for making same  

Microsoft Academic Search

A replaceable insulating sleeve is disposed around the lower end of a drill string used in drilling a well. The sleeve is restrained from rotating relative to the drill string, but can be released and quickly slipped off the drill string in the field to permit rapid replacement if damaged, or if alternate equipment is required. The sleeve carries sensing

H. S. More; C. E. Koch

1984-01-01

46

High voltage supply for neutron tubes in well logging applications  

DOEpatents

A high voltage supply is provided for a neutron tube used in well logging. The "biased pulse" supply of the invention combines DC and "full pulse" techniques and produces a target voltage comprising a substantial negative DC bias component on which is superimposed a pulse whose negative peak provides the desired negative voltage level for the neutron tube. The target voltage is preferably generated using voltage doubling techniques and employing a voltage source which generates bipolar pulse pairs having an amplitude corresponding to the DC bias level.

Humphreys, D. Russell (Albuquerque, NM)

1989-01-01

47

Evaluation of neutron dosimetry techniques for well-logging operations  

SciTech Connect

Neutron dose and energy spectral measurements from /sup 241/AmBe and a 14 MeV neutron generator were performed at a well-logging laboratory. The measurement technique included the tissue equivalent proportional counter, multisphere, two types of remmeters and five types of personnel neutron dosimeters. Several source configurations were used to attempt to relate data to field situations. The results of the measurements indicated that the thermoluminescent albedo dosimeter was the most appropriate personnel neutron dosimeter, and that the most appropriate calibration source would be the source normally employed in the field with the calibration source being used in the unmoderated configuration. 7 refs., 35 figs., 14 tabs.

Cummings, F.M.; Haggard, D.L.; Endres, G.W.R.

1985-07-01

48

A 3-component fiber-optic accelerometer for well logging  

NASA Astrophysics Data System (ADS)

A 3-component (3-C) fiber-optic accelerometer suitable for well logging is presented. The accelerometer can accomplish the 3-C measurement by multiplexing three unidirectional sensing elements which are based on a push-pull mass-spring structure. Experimental results show good linearity, consistency and stability. The suitable measurement frequency range of the system is between 3 and 800 Hz. The on-axis sensitivity, cross-sensitivity and minimum detectable level are 39 dB re rad/g, 14 dB re rad/g and 39.3 ?g/Hz 1/2, respectively.

Zeng, N.; Shi, C. Z.; Zhang, M.; Wang, L. W.; Liao, Y. B.; Lai, S. R.

2004-04-01

49

Chirped CPMG for well-logging NMR applications  

NASA Astrophysics Data System (ADS)

In NMR well-logging, the measurement apparatus typically consists of a permanent magnet which is inserted into a bore, and the sample is the rock surrounding the borehole. When compared to the conditions of standard NMR experiments, this application is thus challenged by relatively weak and invariably inhomogeneous B0 and B1 fields. Chemical shift information is not generally obtained in these measurements. Instead, diffusivity, porosity and permeability information is collected from multi-echo decay measurements - most often using a Carr-Purcell Meiboom-Gill (CPMG) pulse sequence to enhance the experiment’s limited sensitivity. In this work, we explore the consequences of replacing the hard square pulses used in a typical CPMG sequence with chirped pulses sweeping a range of frequencies. The greater bandwidths that for a maximum B1 level can be excited by chirped pulses translates into marked expansion of the detection volume, and thus significant signal-to-noise improvements when compared to standard CPMG acquisitions using hard pulses. This improvement, usually amounting to signal enhancements ?3, can be used to reduce the experimental time of NMR well-logging measurements, for measuring T2 even when B0 and B1 inhomogenieties complicate the measurements, and opening new opportunities in the determination of diffusional properties.

Casabianca, Leah B.; Mohr, Daniel; Mandal, Soumyajit; Song, Yi-Qiao; Frydman, Lucio

2014-05-01

50

Chirped CPMG for well-logging NMR applications.  

PubMed

In NMR well-logging, the measurement apparatus typically consists of a permanent magnet which is inserted into a bore, and the sample is the rock surrounding the borehole. When compared to the conditions of standard NMR experiments, this application is thus challenged by relatively weak and invariably inhomogeneous B0 and B1 fields. Chemical shift information is not generally obtained in these measurements. Instead, diffusivity, porosity and permeability information is collected from multi-echo decay measurements - most often using a Carr-Purcell Meiboom-Gill (CPMG) pulse sequence to enhance the experiment's limited sensitivity. In this work, we explore the consequences of replacing the hard square pulses used in a typical CPMG sequence with chirped pulses sweeping a range of frequencies. The greater bandwidths that for a maximum B1 level can be excited by chirped pulses translates into marked expansion of the detection volume, and thus significant signal-to-noise improvements when compared to standard CPMG acquisitions using hard pulses. This improvement, usually amounting to signal enhancements ?3, can be used to reduce the experimental time of NMR well-logging measurements, for measuring T2 even when B0 and B1 inhomogenieties complicate the measurements, and opening new opportunities in the determination of diffusional properties. PMID:24674888

Casabianca, Leah B; Mohr, Daniel; Mandal, Soumyajit; Song, Yi-Qiao; Frydman, Lucio

2014-05-01

51

Prediction of thermal conductivity of sedimentary rocks from well logs  

NASA Astrophysics Data System (ADS)

The calculation of heat-flow density in boreholes requires reliable values for the change of temperature and rock thermal conductivity with depth. As rock samples for laboratory measurements of thermal conductivity (TC) are usually rare geophysical well logs are used alternatively to determine TC. A common procedure in the latter approach is the use of empirical relations between TC and different petrophysical properties. Although numerous prediction equations were developed in the past five decades, none of these seem to be universally applicable for all major types of sedimentary rocks (clastics, carbonates and evaporites). In addition, these relations mostly are suitable only for regions and lithotypes for which they were originally developed. A new set of predictive equations is presented which overcomes these limitations and which allows the prediction of the rock matrix TC based on different combinations of standard geophysical well-logs. In combination with a feasible mixing-model (i.e. geometric mean model) bulk TC is computed along borehole profiles. The underlying approach was proposed by Fuchs & Förster (2014) and rests upon the detailed analysis of the interrelations between major physical parameters (i.e. thermal conductivity, density, hydrogen index, sonic interval transit time, gamma-ray response, photoelectric factor) of artificial mineral assemblages consisting 15 rock-forming minerals that are used in different combinations to typify sedimentary rocks. The predictive capacity of the new equations is evaluated on subsurface data from four boreholes drilled into the Mesozoic sequence of the North German Basin, including more than 1700 laboratory-measured thermal-conductivity values. Results are compared with those from other approaches published in the past. The new approach predicts TC with a mean error between 10 and 15 % compared to earlier approaches of much higher error of 15-35 % (and sometimes higher).

Fuchs, Sven; Förster, Andrea

2014-05-01

52

Color images of Kansas subsurface geology from well logs  

USGS Publications Warehouse

Modern wireline log combinations give highly diagnostic information that goes beyond the basic shale content, pore volume, and fluid saturation of older logs. Pattern recognition of geology from logs is made conventionally through either the examination of log overlays or log crossplots. Both methods can be combined through the use of color as a medium of information by setting the three color primaries of blue, green, and red light as axes of three dimensional color space. Multiple log readings of zones are rendered as composite color mixtures which, when plotted sequentially with depth, show lithological successions in a striking manner. The method is extremely simple to program and display on a color monitor. Illustrative examples are described from the Kansas subsurface. ?? 1986.

Collins, D. R.; Doveton, J. H.

1986-01-01

53

Hydraulic parameters estimation from well logging resistivity and geoelectrical measurements  

NASA Astrophysics Data System (ADS)

In this paper, a methodology is suggested for deriving hydraulic parameters, such as hydraulic conductivity or transmissivity combining classical hydrogeological data with geophysical measurements. Estimates values of transmissivity and conductivity, with this approach, can reduce uncertainties in numerical model calibration and improve data coverage, reducing time and cost of a hydrogeological investigation at a regional scale. The conventional estimation of hydrogeological parameters needs to be done by analyzing wells data or laboratory measurements. Furthermore, to make a regional survey many wells should be considered, and the location of each one plays an important role in the interpretation stage. For this reason, the use of geoelectrical methods arises as an effective complementary technique, especially in developing countries where it is necessary to optimize resources. By combining hydraulic parameters from pumping tests and electrical resistivity from well logging profiles, it was possible to adjust three empirical laws in a semi-confined alluvial aquifer in the northeast of the province of Buenos Aires (Argentina). These relations were also tested to be used with surficial geoelectrical data. The hydraulic conductivity and transmissivity estimated in porous material were according to expected values for the region (20 m/day; 457 m2/day), and are very consistent with previous results from other authors (25 m/day and 500 m2/day). The methodology described could be used with similar data sets and applied to other areas with similar hydrogeological conditions.

Perdomo, S.; Ainchil, J. E.; Kruse, E.

2014-06-01

54

Fluid-Rock Characterization and Interactions in NMR Well Logging  

SciTech Connect

The objective of this project is to characterize the fluid properties and fluid-rock interactions that are needed for formation evaluation by NMR well logging. This is the first annual progress report submitted to the DOE. It reports on the work completed during the reporting period even if it may have started before this period. This project is a partnership between Professor George J. Hirasaki at Rice University and Professor Kishore Mohanty at University of Houston. In addition to the DOE, this project is supported by a consortium of oil companies and service companies. The fluid properties characterization has emphasized the departure of live oils from correlations based on dead oils. Also, asphaltic components can result in a difference between the T1 and T2 relaxation time distributions as well as reduce the hydrogen index. The fluid rock characterizations that are reported here are the effects of wettability and internal magnetic field gradients. A pore reconstruction method ha s been developed to recreate three-dimensional porous media from two-dimensional images that reproduce some of their key statistical properties. A Monte Carlo simulation technique has been developed to calculate the magnetization decay in fluid saturated porous media given their pore structure.

Hirasaki, George J.; Mohanty, Kishore, K.

2001-07-13

55

Apparatus and method for logging wells while drilling  

SciTech Connect

This patent describes an apparatus and method for logging wells while drilling for detecting electrical data reflective of geological conditions generally ahead of a drill bit in a well and communicating such data to ground surface via an electrically conductive drill string. This apparatus consists of: excitation source means for inducing alternating electrical excitation currents to flow through earth strata surrounding the drill bit; an elongated, electrically conductive, cylindrical module forming a drill collar means connected in the drill string proximate the drill bit at the lower end of the drill string; a bi-directional remote coupler including, an electrically conductive cylindrical coupler housing forming a part of the conductive drill string above the module; a remote relay toroidal transformer means encircling a cross-sectional area coaxially within the coupler housing and having one lead of its toroidal winding electrically connected to the coupler housing; an insulated conductor of predetermined length electrically connected between the other lead of the toroidal winding and a wiper contactor contacting the module at a point below the first signal coupling means, the first signal coupling means inducing the data signals in the insulated conductor, the conductor communicating the data signals to the remote relay toroidal transformer means which in turn couples the data signals into the drill string.

Macleod, N.C.

1986-03-25

56

A novel method for the inversion of the virtual well-log interval transit time  

Microsoft Academic Search

By analyzing the relation between well-log data and seismic data, a novel method for predicting the virtual well-log interval transit time based on particle swarm optimization and support vector machine (PSO-SVM) is proposed. A prediction model for the virtual well-log interval transit time is established using the data of seismic of the un-drilled well, seismic and well-log of the drilled

Hai Ma; Yanjiang Wang

2008-01-01

57

Symposium on high-temperature well-logging instrumentation  

SciTech Connect

The symposium contains papers about developments in borehole logging instrumentation that can withstand downhole temperatures in excess of 300/sup 0/C and pressures greater than 103 MPa. Separate abstracts have been prepared for individual papers. (ACR)

Dennis, B.R. (comp.)

1986-06-01

58

Well Logging and Logging Analysis of UHP metamorphic Rocks in CCSD Main Hole (0-2000m)  

NASA Astrophysics Data System (ADS)

CCSD logging engineering gather many modern high technologies and employs various advanced logging tools to survey the sidewall continuously. This can obtain various physical, chemical, geometrical, etc in-situ information of the borehole's profile. So well logging is one of the most important parts and pivotal technologies in the project of CCSD. The main logging methods in CCSD-MH(0-2000m) are laterolog (Rd,Rs), gamma ray(GR), nature gamma spectrometry(U, TH, K), density(DEN), photo electric section exponent (Pe), compensated neutron(CNL), multipole array acoustic (Vp, Vs, Vst), Simultaneous Acoustic-Resistivity-image(Star-II), temperature(T),magnetic susceptibility(MS), three component borehole magnetic and redox potential log,etc. The various metamorphic rocks can be classified by logging curves,and their physical parameters can be acquired by analyzing the response characters of various metamorphic rocks and by statistics. According to the logging cross plot, We can research the clustering of metamorphite's physical property. Five lithologic segments can be obtainend by logging curves. The GR, Th, U, K logging values of segment 1 is lower than the third, fourth and fiveth segment, higher than segment 2; The DEN, Pe values of segment 1 higher than the third, fourth and fiveth segments. The main rocks in segment 1,2,3,4,5 are eclogites, serpentinites, paragneiss, orthogneiss, and eclogites(containing silicon and muscovite ) respectively. Generally, eclogite contain rutile, silicon, muscovite, etc. minerals. These minerals have response obviously on log curves.There are rutile,ilmenite, pyrite mineralized, etc. Making use of DEN, Pe, susceptibility log values, these mineralized layers can be goodly demarcation. For example, on the rutile mineralzed layer, the logging curve response characters are of high density and Pe obviously. The key data of the synthetical seismic record is wave impedance. In this paper, Utilize the data of AC, DEN curves to calculate the wave impedance and compare with the VSP profile, finally analyze the reflectors of the CCSD-MH. Imaging log has a positioning system and very good vertical resolution, and can describe the geological features in detail. Various structure parameters (the size and occurrences of foliation, fracture, fault & vein) have been given by image logging. The main work of logging interpretation of CCSD have done as follows: 1) Character analysis of logging response and restoring the lithologic profile;2) Depth correction and Restoring orientation of cores; 3) Interpretation of imaging geological feature; 4) Research of rock's mechanics character, sonic anisotropy and formation stress; 5) Comparison wave impedance with the VSP profile,analyzing the reflectors; 6)The interpretation of magnetic susceptibility and temperature log. The logging analysis results of UHP metamorphic rocks in CCSD-MH(0-2000m) show that responses of logs curve are abundant, the physical properties of various metamorphic rocks are visibly different;image logging has a positioning system and very good vertical resolution, and can describe the geological features in detail;lithologic segments and mineralized layers can be goodly demarcation by log curves;the log curves can be used for standardizing the geophysical survey, for example, mark out the reflected interface of seismic wave;comparing the results of log curves value with core laboratory analysis,they have good consistency;and so on.

Pan, H.; Niu, Y.; Wang, W.; Zhu, L.; Xu, D.; Wu, H.; Li, S.; Luo, M.

2004-12-01

59

An index of geophysical well logging in Virginia by the U.S. Geological Survey  

USGS Publications Warehouse

Geophysical logs have been obtained in more than 170 wells in Virginia by the U.S. Geological Survey since 1968. These logs include natural gamma, electric, caliper, temperature, fluid conductivity, and fluid velocity. Most of the logs are for wells in the Coastal Plain Province of eastern Virginia. Geophysical logs aid in the interpretation of properties of earth materials, including the capacity to store and transmit water in the immediate vicinity of the well bore.

Mulheren, M. Patrick.; Larson, J. D.; Hopkins, Herbert T.

1982-01-01

60

Thermal conductivity from core and well log data  

Microsoft Academic Search

The relationships between thermal conductivity and other petrophysical properties have been analysed for a borehole drilled in a Tertiary Flysch sequence. We establish equations that permit us to predict rock thermal conductivity from logging data. A regression analysis of thermal conductivity, bulk density, and sonic velocity yields thermal conductivity with an average accuracy of better than 0.2W(mK)-1. As a second

Andreas Hartmann; Volker Rath; Christoph Clauser

2005-01-01

61

Downhole well log and core montages from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope  

USGS Publications Warehouse

The BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well was an integral part of an ongoing project to determine the future energy resource potential of gas hydrates on the Alaska North Slope. As part of this effort, the Mount Elbert well included an advanced downhole geophysical logging program. Because gas hydrate is unstable at ground surface pressure and temperature conditions, a major emphasis was placed on the downhole-logging program to determine the occurrence of gas hydrates and the in-situ physical properties of the sediments. In support of this effort, well-log and core data montages have been compiled which include downhole log and core-data obtained from the gas-hydrate-bearing sedimentary section in the Mount Elbert well. Also shown are numerous reservoir parameters, including gas-hydrate saturation and sediment porosity log traces calculated from available downhole well log and core data. ?? 2010.

Collett, T. S.; Lewis, R. E.; Winters, W. J.; Lee, M. W.; Rose, K. K.; Boswell, R. M.

2011-01-01

62

Borehole logging for radium-226: recommended procedures and equipment. Final report  

Microsoft Academic Search

Field investigations and a literature review were conducted to determine whether existing well-logging techniques are suitable for measuring ˛˛Ra at remedial action sites. These methods include passive gamma-ray measurement techniques using NaI(Tl) and, occasionally, intrinsic germanium detectors. Parameters that must be considered when logging boreholes at remedial action sites include: (1) casing material and thickness, (2) water in the borehole,

K. B. Olsen; V. W. Thomas

1984-01-01

63

Course An Introduction to Geothermal Resources - Well Completion Production Equipment  

SciTech Connect

A course to introduce geothermal energy held in Sparks, Nevada on October 1987. Topics included well draining and well computation production equipment. There is much technical detail and some cost detail. [DJE-2005

Ascuaga, John; Garrett, B.D. (Slim)

1987-10-01

64

Regional well-log correlation in the New Mexico portion of the Delaware Basin  

SciTech Connect

Although well logs provide the most complete record of stratigraphy and structure in the northern Delaware Basin, regional interpretations of these logs generate problems of ambiguous lithologic signatures and on-hole anomalies. Interpretation must therefore be based on log-to-log correlation rather than on inferences from single logs. In this report, logs from 276 wells were used to make stratigraphic picks of Ochoan horizons (the Rustler, Salado, and Castile Formations) in the New Mexico portion of the Delaware Basin. Current log correlation suggests that: (1) the Castile is characterized by lateral thickening and thinning; (2) some Castile thinnings are of Permian age; (3) irregular topography in the Guadalupian Bell Canyon Formation may produce apparent structures in the overlying Ochoan units; and (4) extensive dissolution of the Salado is not apparent in the area of the Waste Isolation Pilot Project (WIPP) site. 13 refs., 37 figs.

Borns, D.J.; Shaffer, S.E.

1985-09-01

65

Photoelectric log data aids deep-well completion decisions  

SciTech Connect

In several deep, overpressured wells in Oklahoma and Louisiana, Apache Corp. has used photoelectric measurements provided by wireline density tools to aid in completion decisions. The information helped identify permeable zones in several tight formations; these zones were subsequently perforated, hydraulically fractured and successfully produced. Because formation conditions and small borehole sizes precluded running traditional micrologs as permeability indicators, the photoelectric information proved to be particularly valuable on these wells. The operating principles of the tool, supplied by Halliburton Energy Services, are presented here. And example applications in Caddo County, Oklahoma, and Jackson Parish, Louisiana, deep wells are presented.

Maher, T.M. [Apache Corp., Tulsa, OK (United States); Boykin, W. [Halliburton Energy Services, Oklahoma City, OK (United States); Heysse, D.R. [Halliburton Energy Services, Houston, TX (United States)

1997-09-01

66

Well log-seismic sequence and stratigraphy analysis: An integrated approach to exploration and development  

Microsoft Academic Search

Well log-seismic sequence stratigraphy analysis is a new technology that integrates high-resolution biostratigraphic and paleobathymetric data and the characteristics of the well log signatures with seismic reflection profiles. This methodology permits the biostratigrapher, geologist, and geophysicist to work together to subdivide a stratigraphic section into packages of sediments bounded by chronostratigraphically significant condensed sections and their associated maximum flooding surfaces

P. R. Vail; W. W. Jr. Wornardt

1991-01-01

67

Well log interpretation of certain geothermal fields in the Imperial Valley, California  

SciTech Connect

This study reviews the wireline log responses of some geothermal fields in the Imperial Valley, California. The fields under study include the Heber, the East Mesa, the Brawley, and the Westmoreland. The well logs used in the study did not include all the wireline surveys obtained by the operators. The selected well logs obtained under special arrangements with the operators were chosen to maintain the anonymity of specific well locations but are only representative of each area. Analysis of the well logs indicates that on an individual field basis, the well logs are excellent for correlation purposes. The presence of extremely saline fluids in some fields precludes the monitoring of Q/sub v/ (cation exchange capacity per unit volume) profile for detection of hydrothermally altered zones. The producing sections in all the fields are characterized by low porosity and high resistivity.

Ershaghi, I.; Abdassah, D.

1984-03-01

68

Prospect generation using digital well log data - Minnelusa formation  

Microsoft Academic Search

Trapping in the Permian Minnelusa Formation is almost entirely stratigraphic. Much of the oil is trapped in buried hilltops controlled by the unconformity at the top of the Minnelusa. Highly localized stratigraphic changes within the upper Minnelusa are also important. The database used for computer mapping of the Minnelusa play includes cartographic data, formation and zone tops, and digital well

Shier

1985-01-01

69

Photoelectric log data aids deep-well completion decisions  

Microsoft Academic Search

In several deep, overpressured wells in Oklahoma and Louisiana, Apache Corp. has used photoelectric measurements provided by wireline density tools to aid in completion decisions. The information helped identify permeable zones in several tight formations; these zones were subsequently perforated, hydraulically fractured and successfully produced. Because formation conditions and small borehole sizes precluded running traditional micrologs as permeability indicators, the

T. M. Maher; W. Boykin; D. R. Heysse

1997-01-01

70

Plutonium well logging with the photoneutron uranium exploration system  

SciTech Connect

The Los Alamos National Laboratory prototype photoneutron uranium exploration system was recently demonstrated at the Hanford site near Richland, Washington, for Rockwell-Hanford Operations (Rockwell). The demonstration determined the field performance capabilities of the uranium exploration system for in situ, downhole measurements of transuranic waste concentrations. The uranium exploration system is indeed capable of detecting plutonium in the test wells at the waste sites investigated. The excellent signal-to-background ratio (15:1 in the worst case) of the system made positive plutonium determinations possible despite neutron backgrounds caused by spontaneous fission and (..cap alpha..,n) emitters. We present all the data collected from seven test wells and guidance for interpreting the data relative to the known uranium ore calibration of the system. The demonstration indicated no operational difficulties in the waste site environment, and routine use by Rockwell personnel appears practical.

Baker, M.P.; Marks, T.

1982-09-01

71

Did you smooth your well logs the right way for seismic interpretation?  

Microsoft Academic Search

Correlations between physical properties and seismic reflection data are useful to determine the geological nature of seismic reflections and the lateral extent of geological strata. The difference in resolution between well logs and seismic data is a major hurdle faced by seismic interpreters when tying both data sets. In general, log data have a resolution of at least two orders

Mathieu J. Duchesne; Philippe Gaillot

2011-01-01

72

Determination of TDS in Geothermal Systems by Well-Log Analysis  

SciTech Connect

An estimate of t h e chemistry of the fluid within a geothermal reservoir is required to establish the geological source and the possible environmental impact of the fluid as well as scaling and corrosion problems which might develop during production. While a detailed analysis of the chemical composition of a geothermal fluid can only be obtained from a water sample, an estimate of the total dissolved solids (TDS) in equivalent sodium chloride (NaCl) concentration can be obtained from well logs. TDS can also be useful in geological correlation between wells. TDS can be determined directly from a pulsed neutron log and a porosity log, (if the type of formation is known), or from the water resistivity, R{sub w}, and the temperature, T. Three approaches are used to find R{sub w}, and thus TDS. The first method uses a dual induction focused log and information from the log heading. Next, is found by employing an electrical log and a porosity log. The last approach utilizes the spontaneous potential log and header data. Examples are provided to illustrate the techniques described which utilize calculated values of R{sub w} to determine TDS.

Brown, Susan L.; Gobran, Brian D.; Sanyal, Subir K.

1980-12-16

73

Log ASCII Standard (LAS) Files for Geophysical (Gamma Ray) Wireline Well Logs and Their Application to Geologic Cross Section C-C' Through the Central Appalachian Basin  

USGS Publications Warehouse

U.S. Geological Survey (USGS) regional geologic cross section C-C' (Ryder and others, 2008) displays key stratigraphic intervals in the central Appalachian basin. For this cross section, strata were correlated by using descriptions of well cuttings and gamma ray well log traces. This report summarizes the procedures used to convert gamma ray curves on paper well logs to the digital Log ASCII (American Standard Code for Information Interchange) Standard (LAS) format using the third-party software application Neuralog. The procedures could be used with other geophysical wireline logs also. The creation of digital LAS files from paper well logs by using Neuralog is very helpful, especially when dealing with older logs with limited or nonexistent digital data. The LAS files from the gamma ray logs of 11 wells used to construct cross section C-C' are included in this report. They may be downloaded from the index page as a single ZIP file.

Trippi, Michael H.; Crangle, Robert D., Jr.

2009-01-01

74

Did you smooth your well logs the right way for seismic interpretation?  

NASA Astrophysics Data System (ADS)

Correlations between physical properties and seismic reflection data are useful to determine the geological nature of seismic reflections and the lateral extent of geological strata. The difference in resolution between well logs and seismic data is a major hurdle faced by seismic interpreters when tying both data sets. In general, log data have a resolution of at least two orders of magnitude greater than seismic data. Smoothing physical property logs improves correlation at the seismic scale. Three different approaches were used and compared to smooth a density log: binomial filtering, seismic wavelet filtering and discrete wavelet transform (DWT) filtering. Regression plots between the density logs and the acoustic impedance show that the data smoothed with the DWT is the only method that preserves the original relationship between the raw density data and the acoustic impedance. Smoothed logs were then used to generate synthetic seismograms that were tied to seismic data at the borehole site. Best ties were achieved using the synthetic seismogram computed with the density log processed with the DWT. The good performance of the DWT is explained by its adaptive multi-scale characteristic which preserved significant local changes of density on the high-resolution data series that were also pictured at the seismic scale. Since synthetic seismograms are generated using smoothed logs, the choice of the smoothing method impacts on the quality of seismic-to-well ties. This ultimately can have economical implications during hydrocarbon exploration or exploitation phases.

Duchesne, Mathieu J.; Gaillot, Philippe

2011-12-01

75

On exploring heterogeneities from well logs using the empirical mode decomposition  

NASA Astrophysics Data System (ADS)

In contrast with the traditional analysis approaches, the Empirical Mode Decomposition (EMD) allows to study nonlinear and nonstationary data. Here, this technique is used to perform a scale-based decomposition from Algerian well logs and to investigate heterogeneities of the layers crossed by the wells. First, the well log data are decomposed into intrinsic mode functions (IMFs). Then, the total depth interval is divided into lithological subintervals. For each subinterval, we compute the mean wavenumber (km) of each mode (m). It is shown that the EMD method behaves as an almost dyadic filter bank, and the heterogeneity of each lithological subinterval can be measured using a scaling parameter value computed as the slope of a linear regression of the plot km vs. m in the log-linear graph. It is worth noting that this parameter can be used to describe underground heterogeneities. Keywords: empirical mode decomposition (EMD), well logs, multi-scale.

Gaci, Said; Zaourar, Naima; Hachay, Olga

2014-05-01

76

Results of well logging operations at the Ahuachapan geothermal field, El Salvador  

SciTech Connect

Well logging operations were performed in eight of the geothermal wells at Ahucachapan. A series of high temperature instruments, including temperature/rabbit, caliper, fluid velocity/temperature/pressure (STP) and fluid sampler were deployed in each well. The caliper tool was used primarily to determine the possible chemical desposit buildup in the casing or liner, and in one well to investigate a suspected break in the casing. STP logs were obtained from six of the eight wells at various flow rates ranging from 30 to 70 kg/s. A static STP log was also run with the wells shut in to provide data to be used in the thermodynamic analysis of several production wells. 23 refs., 1 tab.

Dennis, B.; Jermance, R.; Lawton, R.; Quintinilla, A.; Berganza, J.

1988-01-01

77

Drilling, construction, and caliper-log data for well 3-3505-26, Opaeula exploratory well, Oahu, Hawaii  

USGS Publications Warehouse

The Opaeula exploratory well (State well number 3-3505-26) was drilled about 1.2 miles east- southeast of the town of Haleiwa. The well is located on agricultural land in the Waialua ground-water area. The well was drilled at an elevation of about 287 feet above mean sea level and penetrates about 75 feet into a basalt aquifer. Well-construction data, logs of drilling notes, geologic descriptions for the samples, and caliper-log data are presented for the well. The well is one of 12 exploratory wells drilled in the north-central Oahu area between July 1993 and May 1994 in cooperation with the Honolulu Board of Water Supply.

Presley, T. K.; Oki, D. S.

1996-01-01

78

Drilling, construction, and caliper-log data for well 3-3503-01, North Upper Anahulu exploratory well, Oahu, Hawaii  

USGS Publications Warehouse

The North Upper Anahulu exploratory well (Hawaii State well number 3-3503-01) was drilled about 3.1 miles east of the town of Haleiwa. The well is located on agricultural land in the Kawailoa ground-water area. The well was drilled to an elevation of about -103 feet below mean sea level and penetrates about 110 feet into a basalt aquifer. Well-construction data, logs of drilling notes, geologic descriptions for the samples, and caliper-log data are presented for the well. The well is one of 12 exploratory wells drilled in the north-central Oahu area between July 1993 and May 1994 in cooperation with the Honolulu Board of Water Supply.

Presley, T. K.; Oki, D. S.

1996-01-01

79

Drilling, construction, and caliper-log data for well 3-3505-25, North Lower Anahulu exploratory well, Oahu, Hawaii  

USGS Publications Warehouse

The North Lower Anahulu exploratory well (State well number 3-3505-25) was drilled about 1.4 miles east-northeast of the town of Haleiwa. The well was drilled on agricultural land in the Kawailoa ground-water area. The well was drilled from an elevation of about 232 feet above mean sea level and penetrates about 22 feet into a basalt aquifer. Well-construction data, logs of drilling notes, geologic descriptions for the samples, and caliper-log data are presented for the well. The well is one of 12 exploratory wells drilled in the north-central Oahu area between July, 1993 and May, 1994 in cooperation with the Honolulu Board of Water Supply.

Presley, T. K.; Oki, D. S.

1996-01-01

80

Compilation of 29 sonic and density logs from 23 oil test wells in western Washington State  

USGS Publications Warehouse

Three-dimensional velocity models for Puget Sound provide a means for better understanding the lateral variations in strong ground motions recorded during local earthquakes in Puget Lowland. We have compiled 29 sonic and density logs from 23 oil test wells to help us determine the geometry and physical properties of the Cenozoic basins in western Washington. The maximum depths sampled by the test wells are between 0.47 and 4.04 km. These well logs sample Quaternary to Eocene sedimentary and volcanic rocks. This report presents the locations, elevations, depths, stratigraphic and other information about the test wells, and provides plots showing the density and sonic velocities as a function of depth for each well log. We also present two-way travel times calculated from the sonic velocities.

Brocher, Thomas M.; Ruebel, April L.

1998-01-01

81

A DFA approach in well-logs for the identification of facies associations  

NASA Astrophysics Data System (ADS)

Well-log analysis is a useful tool for the lithological description of wells. Its adequate interpretation allows determining different rock properties such as permeability, density, resistivity and porosity among others. However, given the complexity inherent in the signals, the identification of lithological properties from well-log analysis is not an easy task. In this work, an alternative methodology for sedimentary facies identification based on the detrended fluctuation analysis (DFA) is presented. Our methodology has been calibrated using information from a reference well located at the Chicontepec formation of the Tampico-Misantla basin in Mexico. Its characterization includes the interpretation of different well-logs and cores. Our results indicate that well-log signals present fractal characteristics exhibiting long-range memory. For the gamma ray, resistive and sonic logs a direct relationship between the scaling exponent as a function of the depth and rock types is observed. In this way, the fractal scaling exponents estimated with DFA can be used to identify different sedimentary facies.

Hernandez-Martinez, Eliseo; Velasco-Hernandez, Jorge X.; Perez-Muńoz, Teresa; Alvarez-Ramirez, Jose

2013-12-01

82

Geophysical Logs of Selected Test Wells at the Diaz Chemical Superfund Site in Holley, New York  

USGS Publications Warehouse

In June and July 2006, geophysical logs were collected and analyzed along with rock-core samples to define the bedrock stratigraphy and flow zones penetrated by four test wells at the Diaz Chemical Superfund site at Holley in eastern Orleans County, New York. The work was completed as a preliminary part of the investigation of contamination by organic compounds in the shale, mudstone, and sandstone bedrock. The geophysical logs included natural-gamma, caliper, borehole image, fluid properties, and flowmeter data. The orientation of fractures in the boreholes was inferred from the log data and summarized in stereo and tadpole plots; the transmissivity and hydraulic head was also determined for fracture zones that were observed to be hydraulically active through the flowmeter logs. The data are intended in part for use in the remediation of the site.

Eckhardt, David A. V.; Anderson, J. Alton

2007-01-01

83

Results of investigations at the Zunil geothermal field, Guatemala: Well logging and brine geochemistry  

Microsoft Academic Search

The well logging team from Los Alamos and its counterpart from Central America were tasked to investigate the condition of four producing geothermal wells in the Zunil Geothermal Field. The information obtained would be used to help evaluate the Zunil geothermal reservoir in terms of possible additional drilling and future power plant design. The field activities focused on downhole measurements

Andrew Adams; B. Dennis; E. Van Eeckhout; F. Goff; R. Lawton; P. E. Trujillo; D. Counce; J. Archuleta; V. Medina

1991-01-01

84

DETERMINATION OF HYDRAULIC CONDUCTIVITY AND POROSITY LOGS IN WELLS WITH A DISTURBED ANNULUS  

EPA Science Inventory

A method is developed to determine the Hydraulic conductivity and porosity of the formation surrounding a well as a function of depth. n electrically anomalous fluid is injected into a fully screened well and the radius of invasion is determined by induction logging. he radius of...

85

Estimating pore-space gas hydrate saturations from well log acoustic data  

USGS Publications Warehouse

Relating pore-space gas hydrate saturation to sonic velocity data is important for remotely estimating gas hydrate concentration in sediment. In the present study, sonic velocities of gas hydrate–bearing sands are modeled using a three-phase Biot-type theory in which sand, gas hydrate, and pore fluid form three homogeneous, interwoven frameworks. This theory is developed using well log compressional and shear wave velocity data from the Mallik 5L-38 permafrost gas hydrate research well in Canada and applied to well log data from hydrate-bearing sands in the Alaskan permafrost, Gulf of Mexico, and northern Cascadia margin. Velocity-based gas hydrate saturation estimates are in good agreement with Nuclear Magneto Resonance and resistivity log estimates over the complete range of observed gas hydrate saturations.

Lee, Myung W.; Waite, William F.

2008-01-01

86

Methods for interpretation of tensor induction well logging in layered anisotropic formations  

NASA Astrophysics Data System (ADS)

One of the most challenging problems in the field of electromagnetic well logging is the development of interpretation methods for the characterization of conductivity anisotropy in an earth formation. Response of a triaxial electromagnetic induction well logging instrument is examined. This instrument detects three components of the magnetic field due to each of three transmitters for a total of nine signals. The conductivity anisotropy of the medium can be resolved from the instrument response. This information includes not only the vertical and horizontal conductivities, but also the orientation of the logging instrument axis with respect to the principal tensor axes. Formulas for the apparent horizontal and vertical conductivities, the apparent anisotropy coefficient, and the apparent relative deviation angle are introduced. A new method of induction logging based on electrical measurements is investigated. Electrical tensor components are studied in an unbounded, homogeneous, transversely isotropic, conductive medium. Low frequency asymptotic approximations of the analytical solution are derived. The important result is that by measuring the in-phase components of the electrical tensor, the principal values of the conductivity tensor can be obtained. The basic principles of tensor induction logging two-, three-, and multilayer anisotropic formations in vertical and deviated wells are examined by using numerical simulation of the tensor logs. A technique for correct reconstruction of the apparent conductivities of the anisotropic formations is introduced, based on application of a regularized Newton method. The method is fast and provides real time interpretation. The practical effectiveness of this technique for tensor induction log interpretation is illustrated using results of numerical experiments. The theoretical formulas for the tensor apparent conductivities of the transversely isotropic medium are studied and developed for an ideal tensor induction instrument with coinciding positions of three mutually orthogonal transmitters at one point and all three receivers at the other point in a borehole. Formulas can be corrected for practical instrument design. Corrected formulas for a practical tensor induction well logging instrument are introduced. The numerical study shows, that for various anisotropy values, corrected apparent conductivities are practically the same as the theoretical apparent parameters. A new technique for interpretation of tensor induction well logging (TIWL) data is presented. This method is called sharp boundary inversion, based on using specially selected stabilizing functionals, which minimize the area where strong model parameter variations and discontinuities occur. The method recovers the sharp boundary between various anisotropic geoelectrical layers and reconstructs both horizontal and vertical resistivity profiles. The new TIWL interpretation methods are illustrated by application to the synthetic models of layered anisotropic formations. These methods are applied to the typical benchmark petrophysical models.

Peksen, Ertan

87

30 CFR 250.1623 - Well-control fluids, equipment, and operations.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Well-control fluids, equipment, and operations...SHELF Sulphur Operations § 250.1623 Well-control fluids, equipment, and operations. (a) Well-control fluids, equipment, and...

2013-07-01

88

Log ASCII Standard (LAS) Files for Geophysical Wireline Well Logs and Their Application to Geologic Cross Sections Through the Central Appalachian Basin  

USGS Publications Warehouse

Introduction The U.S. Geological Survey (USGS) uses geophysical wireline well logs for a variety of purposes, including stratigraphic correlation (Hettinger, 2001, Ryder, 2002), petroleum reservoir analyses (Nelson and Bird, 2005), aquifer studies (Balch, 1988), and synthetic seismic profiles (Kulander and Ryder, 2005). Commonly, well logs are easier to visualize, manipulate, and interpret when available in a digital format. In recent geologic cross sections E-E' and D-D', constructed through the central Appalachian basin (Ryder, Swezey, and others, in press; Ryder, Crangle, and others, in press), gamma ray well log traces and lithologic logs were used to correlate key stratigraphic intervals (Fig. 1). The stratigraphy and structure of the cross sections are illustrated through the use of graphical software applications (e.g., Adobe Illustrator). The gamma ray traces were digitized in Neuralog (proprietary software) from paper well logs and converted to a Log ASCII Standard (LAS) format. Once converted, the LAS files were transformed to images through an LAS-reader application (e.g., GeoGraphix Prizm) and then overlain in positions adjacent to well locations, used for stratigraphic control, on each cross section. This report summarizes the procedures used to convert paper logs to a digital LAS format using a third-party software application, Neuralog. Included in this report are LAS files for sixteen wells used in geologic cross section E-E' (Table 1) and thirteen wells used in geologic cross section D-D' (Table 2).

Crangle, Robert D., Jr.

2007-01-01

89

The answer: The definitive Formation evaluation log through well-site information management  

Microsoft Academic Search

Formation evaluation data are currently available at the well site from many different service sources, such as drilling and geological surveillance, formation evaluation measurement while drilling (FE-MWD), and wireline logging. Additional critical data are available from the mud engineer and drilling supervisors. Traditionally, their outputs have been presented inconsistently in a variety of formats, at different scales and data intervals,

J. M. P. Bradley; I. Sindiku; M. Dalton; A. Doyle

1993-01-01

90

Numerical Modeling of Multicomponent Induction Well-Logging Tools in the Cylindrically Stratified Anisotropic Media  

Microsoft Academic Search

In this paper, we present an efficient algorithm to simulate the response of a multicomponent induction well-logging (MCIL) tool in a cylindrically layered anisotropic formation (transversely isotropic media). The tool consists of three pairs of orthogonally arranged transmitter-receiver coils for measuring the magnetic field around a borehole for oil and gas exploration. First, we will derive the EM field components

Hongnian Wang; Poman So; Shouwen Yang; Wolfgang J. R. Hoefer; Huilian Du

2008-01-01

91

Hydrogeochemical investigations in support of well logging operations at the Zunil geothermal field, Guatemala.  

National Technical Information Service (NTIS)

A suite of 41 thermal and nonthermal waters in the Zunil-Quetzaltenango region, Guatemala, were collected as part of a well logging operation conducted by the Instituto Nacional de Electrificacion (INDE) and Los Alamos National Laboratory. Both in situ an...

A. Adams F. Golf P. E. Trujillo D. Counce J. Archuleta

1990-01-01

92

Hydrogeochemical investigations in support of well logging operations at the Zunil geothermal field, Guatemala  

Microsoft Academic Search

A suite of 41 thermal and nonthermal waters in the Zunil-Quetzaltenango region, Guatemala, were collected as part of a well logging operation conducted by the Instituto Nacional de Electrificacion (INDE) and Los Alamos National Laboratory. Both in situ and weirbox samples were collected in the Zunil geothermal field. The various data suggest that the reservoir at Zunil is geochemically inhomogeneous.

A. Adams; F. Golf; P. E. Jr. Trujillo; D. Counce; J. Archuleta; B. Dennis; V. Medina

1990-01-01

93

Method and apparatus for stabilizing signals in radioactive well logging tools  

Microsoft Academic Search

A method and apparatus are presented for stabilizing signals in radioactive well logging tools. In the tool a main scintillating crystal and photomultiplier tube for detecting radiation induced in the borehole by a source of radiation are provided and a reference crystal, including a source of mono-energetic radiation, for producing continuous reference signals of a predetermined energy level. The signals

J. G. Kampfer; L. A. Ingram

1977-01-01

94

Analysis and Summary of Historical Dry Well Gamma Logs for S Tank Farm 200 West  

SciTech Connect

Gross gamma ray logs, recorded from January 1975 through mid-year 1994 as part of the Single-Shell Tank Farm Dry Well Surveillance Program, have been reanalyzed for the S tank farm to locate the presence of mobile radionuclides in the subsurface.

MYERS, D.A.

1999-11-22

95

Benchmarking computer simulations of neutron-induced, gamma-ray spectroscopy for well logging  

Microsoft Academic Search

The spectroscopy of gamma rays created by thermal neutron capture and inelastic scattering of fast neutrons is commonly used in the study of wellbore geophysics. In this type of well logging, a sonde, consisting of a pulsed source of fast neutrons and gamma ray detectors, is pulled through the formations traversed by the borehole. The many geometries, lithologies, reservoir fluids,

Richard C. Odom; Shawn M. Bailey; Robert D. Wilson

1997-01-01

96

Simulation of Electromagnetic Wave Logging Response in Deviated Wells Based on Vector Finite Element Method  

NASA Astrophysics Data System (ADS)

The vector finite element method of tetrahedral elements is used to model 3D electromagnetic wave logging response. The tangential component of the vector field at the mesh edges is used as a degree of freedom to overcome the shortcomings of node-based finite element methods. The algorithm can simulate inhomogeneous media with arbitrary distribution of conductivity and magnetic permeability. The electromagnetic response of well logging tools are studied in dipping bed layers with the borehole and invasion included. In order to simulate realistic logging tools, we take the transmitter antennas consisting of circular wire loops instead of magnetic dipoles. We also investigate the apparent resistivity of inhomogeneous formation for different dip angles.

Lv, Wei-Guo; Chu, Zhao-Tan; Zhao, Xiao-Qing; Fan, Yu-Xiu; Song, Ruo-Long; Han, Wei

2009-01-01

97

Commercial geophysical well logs from the USW G-1 drill hole, Nevada Test Site, Nevada  

USGS Publications Warehouse

Drill hole USW G-1 was drilled at Yucca Mountain, Nevada Test Site, Nevada, as part of the ongoing exploration program for the Nevada Nuclear Waste Storage Investigations. Contract geophysical well logs run at USW G-1 show only limited stratigraphic correlations, but correlate reasonably well with the welding of the ash-flow and ash-fall tuffs. Rocks in the upper part of the section have highly variable physical properties, but are more uniform and predictably lower in the section.

Muller, D. C.; Kibler, J. E.

1983-01-01

98

Commercial geophysical well logs from the USW G-1 drill hole, Nevada Test Site, Nevada  

Microsoft Academic Search

Drill hole USW G-1 was drilled at Yucca Mountain, Nevada Test Site, Nevada, as part of the ongoing exploration program for the Nevada Nuclear Waste Storage Investigations. Contract geophysical well logs run at USW G-1 show only limited stratigraphic correlations, but correlate reasonably well with the welding of the ash-flow and ash-fall tuffs. Rocks in the upper part of the

D. C. Muller; J. E. Kibler

1983-01-01

99

Log ASCII Standard (LAS) Files for Geophysical Wireline Well Logs and Their Application to Geologic Cross Sections through the Central Appalachian Basin.  

National Technical Information Service (NTIS)

The U.S. Geological Survey (USGS) uses geophysical wireline well logs for a variety of purposes, including stratigraphic correlation (Hettinger, 2001, Ryder, 2002), petroleum reservoir analyses (Nelson and Bird, 2005), aquifer studies (Balch, 1988), and s...

R. D. Crangle

2007-01-01

100

Addendum 2: Logs of monitor wells drilled May 1988 through December 1992  

SciTech Connect

The logs in this addendum were plotted in a new format by the same software package (LOGGER by Rockware, Denver, CO) that was used in the original publication. The scale remains the same, 1 inch = 15 foot. The header is totally automated with a subheading indexing the well-construction symbols. Geophysical curves are labeled in their respective channels, and percentage core recovery is plotted in a histogram. Lithologic symbols are plotted to scale in a channel similar to previous logs. The lithologic description also has been automated to assure consistency in terminology. Descriptions are more extensive and are referenced by leader lines to the lithologic symbol. Additional figures included for this Addendum are: a plot of all the monitoring well locations at the LLNL Main site and a plot detailing the gasoline spill area well locations in the vicinity of Building 403.

Stout, J. [Ray Raskin Associates Inc., Tempe, AZ (United States); Qualheim, B. [Lawrence Livermore National Lab., CA (United States); McPherrin, R. [Lawrence Livermore National Lab., CA (United States); Barber, K. [Allied Signal Technical Services, Livermore, CA (United States); Hedegaard, R. [ICF Kaiser Engineers, San Francisco, CA (United States); McConihe, W.; Miller, T. [Brown and Caldwell, Pleasanton, CA (United States)

1993-11-01

101

Volcanic stratigraphy of DSDP/ODP Hole 395A: An interpretation using well-logging data  

NASA Astrophysics Data System (ADS)

Deep Sea Drilling Project/Ocean Drilling Program Hole 395A was drilled approximately 500 m deep into young oceanic crust west of the Mid-Atlantic Ridge. Core recovery is very poor in this hole and therefore continuous downhole measurements are important to understand the drilled lithology. Geophysical downhole measurements were carried out during several cruises. A new set of logs was recorded during Leg 174B in summer 1997. The new logging data show a significant improvement in data quality compared to older measurements from Leg 109. The lithostratigraphy established from cores gives only limited information because of the poor core recovery in this hole. The gaps in the core lithostratigraphy are filled by reconstructing a synthetic lithological profile using the standard well-logging data. Three types of lava morphologies, massive basalts, altered lava flows, and pillow basalts, may be distinguished using the logs because the lava morphologies show differences in their physical properties due to differences in fracturing and alteration. The synthetic lithological profile gives a more detailed and precise vertical definition of single layers than the core profile. The integration of further logging and core data enables a detailed reconstruction of the accretion history at the drill site. Cyclic, upward decreasing trends in the resistivity logs were already observed during earlier cruises and were referred to magmatic cycles. Similar trends occur in the density log and, inversely, in the total gamma ray log. The trends reflect gradual changes in fracturing, porosity, permeability, and alteration and cover depth intervals of several tens of meters. Boundaries between cycles are interpreted to correspond to periods of volcanic quiescence. Two types of boundaries may be identified. Boundaries correlating with reversals in the magnetic field and/or changes in the geochemical composition of the basalts are interpreted as long pauses. Basalts separated by these boundaries were probably fed by separate magma reservoirs. Boundaries identified only by changes in alteration but not in geochemistry are interpreted to represent shorter pauses. They separate basalts that were probably fed by the same magma chamber.

Bartetzko, Anne; Pezard, Philippe; Goldberg, David; Sun, Yue-Feng; Becker, Keir

2001-03-01

102

Statistical factor analysis technique for characterizing basalt through interpreting nuclear and electrical well logging data (case study from Southern Syria).  

PubMed

Factor analysis technique is proposed in this research for interpreting the combination of nuclear well logging, including natural gamma ray, density and neutron-porosity, and the electrical well logging of long and short normal, in order to characterize the large extended basaltic areas in southern Syria. Kodana well logging data are used for testing and applying the proposed technique. The four resulting score logs enable to establish the lithological score cross-section of the studied well. The established cross-section clearly shows the distribution and the identification of four kinds of basalt which are hard massive basalt, hard basalt, pyroclastic basalt and the alteration basalt products, clay. The factor analysis technique is successfully applied on the Kodana well logging data in southern Syria, and can be used efficiently when several wells and huge well logging data with high number of variables are required to be interpreted. PMID:24296157

Asfahani, Jamal

2014-02-01

103

Records of wells, water-level measurements, and drillers' logs, Red River Valley, Louisiana  

USGS Publications Warehouse

This report is a compilation of hydrogeologic data collected through June 1975 as part of the Red River Waterways project in Louisiana. The study was made by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers, New Orleans District, and the U.S. Soil Conservation Service, Alexandria, La. Included are records of 332 wells and test holes, water levels in 324 wells, and drillers ' logs of 316 wells and test holes. Most of the data were collected between July 1968 and June 1975. Well locations are shown. All altitudes given in the tables are referenced to mean sea level. (Woodard-USGS)

Stephens, John W.

1976-01-01

104

Emulation of petroleum well-logging D-T2 correlations on a standard benchtop spectrometer.  

PubMed

An experimental protocol is described that allows two-dimensional (2D) nuclear magnetic resonance (NMR) correlations of apparent diffusion coefficient D(app) and effective transverse relaxation time T(2,eff) to be acquired on a bench-top spectrometer using pulsed field gradients (PFG) in such a manner as to emulate D(app)-T(2,eff) correlations acquired using a well-logging tool with a fixed field gradient (FFG). This technique allows laboratory-scale NMR measurements of liquid-saturated cored rock to be compared directly to logging data obtained from the well by virtue of providing a comparable acquisition protocol and data format, and hence consistent data processing. This direct comparison supports the interpretation of the well-logging data, including a quantitative determination of the oil/brine saturation. The D-T(2) pulse sequence described here uses two spin echoes (2SE) with a variable echo time to encode for diffusion. The diffusion and relaxation contributions to the signal decay are then deconvolved using a 2D numerical inversion. This measurement allows shorter relaxation time components to be probed than in conventional diffusion measurements. A brief discussion of the numerical inversion algorithms available for inverting these non-rectangular data is included. The PFG-2SE sequence described is well suited to laboratory-scale studies of porous media and short T(2) samples in general. PMID:21875819

Mitchell, J; Fordham, E J

2011-10-01

105

Data Mining by MOUCLAS Algorithm for Petroleum Reservoir Characterization from Well Logging Data  

Microsoft Academic Search

Petroleum reservoir characterization is one of the most difficult and challenging tasks of the exporation of petroleum industry\\u000a and usually a long and costly procedure. This paper proposes a novel kind of patterns for the classification over quantitative\\u000a well logging data, which is called MOUCLAS (MOUntain function based CLASsification) Patterns, based on the concept of the fuzzy set membership function

Yalei Hao; Markus Stumptner; Gerald Quirchmayr; Qing He

2004-01-01

106

Lithology determination from well logs with fuzzy associative memory neural network  

SciTech Connect

An artificial intelligence technique of fuzzy associative memory is used to determine rock types from well-log signatures. Fuzzy associative memory (FAM) is a hybrid of neutral network and fuzzy expert system. This new approach combines the learning ability of neural network and the strengths of fuzzy linguistic modeling to adaptively infer lithologies from well-log signatures based on (1) the relationships between the lithology and log signature that the neural network have learned during the training and/or (2) geologist`s knowledge about the rocks. The method is applied to a sequence of the Ordovician rock units in northern Kansas. This paper also compares the performances of two different methods, using the same data set for meaningful comparison. The advantages of FAM are (1) expert knowledge acquired by geologists is fully utilized; (2) this knowledge is augmented by the neural network learning from the data, when available; and (3) FAM is transparent in that the knowledge is explicitly stated in the fuzzy rules.

Chang, H.C.; Chen, H.C.; Fang, J.H. [Univ. of Alabama, Tuscaloosa, AL (United States)

1997-05-01

107

Well logging methods in groundwater surveys of complicated aquifer systems: Bohemian Cretaceous Basin  

NASA Astrophysics Data System (ADS)

Geophysical well logging methods (including borehole flow logging) can significantly contribute to a detailed understanding of hydrogeological conditions in basins with complicated sedimentary structure in studies undertaken to make optimal use of water sources, or to protect those resources from contamination. It is a common practice to delineate geological and hydrogeologic conditions at the scale used in geological maps and surface surveys. However, there is a need for more detailed descriptions of basin structure for many tasks related to water resources management and hydrologic research. This paper presents four specific examples of boreholes in complex hydrogeologic settings where useful information was provided by geophysical logging: (1) identification of large-scale upward cross-flow between aquifer horizons in an open borehole; (2) confirmation of continuous permeability throughout a long borehole interval; (3) identification of leakage into a test well via a defective casing joint; (4) evidence for downward flow in open boreholes; and (5) identification of permeable beds associated with water inflows during aquifer tests. These borehole geophysical measurements provide important information about the detailed lithological profiles of aquifers (especially in the absence of core), enabling the optimization of groundwater monitoring, resource use, and wellhead protection activities.

Datel, Josef V.; Kobr, Miroslav; Prochazka, Martin

2009-05-01

108

Shear wave velocity prediction using seismic attributes and well log data  

NASA Astrophysics Data System (ADS)

Formation's properties can be estimated indirectly using joint analysis of compressional and shear wave velocities. Shear wave data is not usually acquired during well logging, which is most likely for cost saving purposes. Even if shear data is available, the logging programs provide only sparsely sampled one-dimensional measurements: this information is inadequate to estimate reservoir rock properties. Thus, if the shear wave data can be obtained using seismic methods, the results can be used across the field to estimate reservoir properties. The aim of this paper is to use seismic attributes for prediction of shear wave velocity in a field located in southern part of Iran. Independent component analysis (ICA) was used to select the most relevant attributes to shear velocity data. Considering the nonlinear relationship between seismic attributes and shear wave velocity, multi-layer feed forward neural network was used for prediction of shear wave velocity and promising results were presented.

Gholami, Raoof; Moradzadeh, Ali; Rasouli, Vamegh; Hanachi, Javid

2014-03-01

109

Equipping Intelligent Agents with Commonsense Knowledge acquired from Search Query Logs: Results from an Exploratory Story  

NASA Astrophysics Data System (ADS)

Access to knowledge about user goals represents a critical component for realizing the vision of intelligent agents acting upon user intent on the web. Yet, the manual acquisition of knowledge about user goals is costly and often infeasible. In a departure from existing approaches, this paper proposes Goal Mining as a novel perspective for knowledge acquisition. The research presented in this chapter makes the following contributions: (a) it presents Goal Mining as an emerging field of research and a corresponding automatic method for the acquisition of user goals from web corpora, in the case of this paper search query logs (b) it provides insights into the nature and some characteristics of these goals and (c) it shows that the goals acquired from query logs exhibit traits of a long tail distribution, thereby providing access to a broad range of user goals. Our results suggest that search query logs represent a viable, yet largely untapped resource for acquiring knowledge about explicit user goals.

Strohmaier, Markus; Kröll, Mark; Prettenhofer, Peter

110

Preliminary report on geophysical well-logging activity on the Salton Sea Scientific Drilling Project, Imperial Valley, California  

USGS Publications Warehouse

The Salton Sea Scientific Drilling Project has culminated in a 10,564-ft deep test well, State 2-14 well, in the Imperial Valley of southern California. A comprehensive scientific program of drilling, coring, and downhole measurements, which was conducted for about 5 months, has obtained much scientific information concerning the physical and chemical processes associated with an active hydrothermal system. This report primarily focuses on the geophysical logging activities at the State 2-14 well and provides early dissemination of geophysical data to other investigators working on complementary studies. Geophysical-log data were obtained by a commercial logging company and by the U.S. Geological Survey (USGS). Most of the commercial logs were obtained during three visits to the site; only one commercial log was obtained below a depth of 6,000 ft. The commercial logs obtained were dual induction, natural gamma, compensated neutron formation density, caliper and sonic. The USGS logging effort consisted of four primary periods, with many logs extending below a depth of 6,000 ft. The USGS logs obtained were temperature, caliper, natural gamma, gamma spectral, epithermal neutron, acoustic velocity, full-waveform, and acoustic televiewer. Various problems occurred throughout the drilling phase of the Salton Sea Scientific Drilling Project that made successful logging difficult: (1) borehole constrictions, possibly resulting from mud coagulation, (2) maximum temperatures of about 300 C, and (3) borehole conditions unfavorable for logging because of numerous zones of fluid loss, cement plugs, and damage caused by repeated trips in and out of the hole. These factors hampered and compromised logging quality at several open-hole intervals. The quality of the logs was dependent on the degree of probe sophistication and sensitivity to borehole-wall conditions. Digitized logs presented were processed on site and are presented in increments of 1,000 ft. A summary of the numerous factors that may be relevant to this interpretation also is presented. (Lantz-PTT)

Paillet, F. L.; Morin, R. H.; Hodges, H. E.

1986-01-01

111

75 FR 75995 - Request for Comments on Helium-3 Use in the Oil and Natural Gas Well Logging Industry  

Federal Register 2010, 2011, 2012, 2013

...OF ENERGY Request for Comments on Helium-3 Use in the Oil and Natural Gas Well Logging...comments on the volumes and uses of Helium-3 by the oil and gas well logging industry...Allison@hq.doe.gov. Include ``Helium-3 Request for Comments'' in the subject...

2010-12-07

112

Petrophysical characterisation lithology identification of Beda Formation, Sirt basin, Libya using well logging records  

NASA Astrophysics Data System (ADS)

The petrophysical characterisations are one of the most useful and important tools available to petroleum geologist. The petrophysical characterisation have been evaluated to Beda Formation though the analysis of open hole well logging records of four exploratory and development wells, distributed in the Beda Formation of Sirt basin, Libya. These available well logging records have been analyzed though utilizing the petrophysics software (for determining the petrophysical parameters). This is to identify the lithological constituents and saturation parameters. The litho saturation analysis of Beda Formation of the studied wells indicates that it is mainly. The analytical Formation evaluations of some cross plot (e.g. interval transient time & neutron porosity) reveal lithological facies change with different deposition environment. It consists mainly of mixture of limestone and dolomite with subtidal fossiliferous as indicated from true resistivity and neutron porosity crossplot. The true resistivity and sonic porosity crossplot illustrates the disseminated shale is mainly of dispersed type and some of laminated habitat. It also point to the dominance of the intergrnular porosity. The isoparametric maps (weighed values) of petrophysical parameters show that vertical distribution of Beda Formation.

Eljadi, R. E.

2012-12-01

113

High-voltage supply for neutron tubes in well-logging applications  

DOEpatents

A high voltage supply is provided for a neutron tube used in well logging. The biased pulse supply of the invention combines DC and full pulse techniques and produces a target voltage comprising a substantial negative DC bias component on which is superimposed a pulse whose negative peak provides the desired negative voltage level for the neutron tube. The target voltage is preferably generated using voltage doubling techniques and employing a voltage source which generates bipolar pulse pairs having an amplitude corresponding to the DC bias level.

Humphreys, D.R.

1982-09-15

114

Hydrogeochemical investigations in support of well logging operations at the Zunil geothermal field, Guatemala  

SciTech Connect

A suite of 41 thermal and nonthermal waters in the Zunil-Quetzaltenango region, Guatemala, were collected as part of a well logging operation conducted by the Instituto Nacional de Electrificacion (INDE) and Los Alamos National Laboratory. Both in situ and weirbox samples were collected in the Zunil geothermal field. The various data suggest that the reservoir at Zunil is geochemically inhomogeneous. Stable isotope data suggest recharge to the field comes primarily from the north and east whereas tritium data indicate that the reservoir waters may be 500 to 7500 years old. 14 refs., 4 figs., 3 tabs.

Adams, A.; Golf, F.; Trujillo, P.E. Jr.; Counce, D.; Archuleta, J.; Dennis, B. (Los Alamos National Lab., NM (USA)); Medina, V. (Unidad de Desarrollo Geotermico, Guatemala City (Guatemala). Inst. Nacional de Electrificacion)

1990-01-01

115

Electrical resistivity well-logging system with solid-state electronic circuitry  

USGS Publications Warehouse

An improved 4-channel electrical resistivity well-logging system for use with a passive probe with electrodes arranged in the 'normal' configuration has been designed and fabricated by Westinghouse Electric Corporation to meet technical specifications developed by the U.S. Geological Survey. Salient features of the system include solid-state switching and current regulation in the transmitter circuit to produce a constant-current source square wave, and synchronous solid-state switching and sampling of the potential waveform in the receiver circuit to provide an analog dc voltage proportions to the measured resistivity. Technical specifications and design details are included in this report.

Scott, James Henry; Farstad, Arnold J.

1977-01-01

116

Induction conductivity and natural gamma logs collected in 15 wells at Camp Stanley Storage Activity, Bexar County, Texas  

USGS Publications Warehouse

The U.S. Geological Survey, in cooperation with the Camp Stanley Storage Activity conducted electromagnetic induction conductivity and natural gamma logging of 15 selected wells on the Camp Stanley Storage Activity, located in northern Bexar County, Texas, during March 28-30, 2005. In late 2004, a helicopter electromagnetic survey was flown of the Camp Stanley Storage Activity as part of a U.S. Geological Survey project to better define subsurface geologic units, the structure, and the catchment area of the Trinity aquifer. The electromagnetic induction conductivity and natural gamma log data in this report were collected to constrain the calculation of resistivity depth sections and to provide subsurface controls for interpretation of the helicopter electromagnetic data collected for the Camp Stanley Storage Activity. Logs were recorded digitally while moving the probe in an upward direction to maintain proper depth control. Logging speed was no greater than 30 feet per minute. During logging, a repeat section of at least 100 feet was recorded to check repeatability of log responses. Several of the wells logged were completed with polyvinyl chloride casing that can be penetrated by electromagnetic induction fields and allows conductivity measurement. However, some wells were constructed with steel centralizers and stainless steel screen that caused spikes on both conductivity and resulting resistivity log curves. These responses are easily recognizable and appear at regular intervals on several logs.

Stanton, Gregory P.

2005-01-01

117

Logs and completion data for water and mass balance wells in Mortandad and Ten Site Canyons  

SciTech Connect

Twenty-four monitoring wells were drilled and completed in December 1994 as part of a water and mass balance study for the shallow perched aquifer in the Mortandad Canyon alluvium and in the lower part of Ten-Site Canyon. The wells penetrated the alluvium containing the aquifer and were completed into the top of the weathered tuff. Twelve of these wells encountered the Tshirege Member (Cooing Unit 1 g) of the Bandelier Tuff below the canyon alluvium, while ten wells made contact with the Cerro Toledo interval, which lies between the Tshirege and Otowi Members of the Bandelier Tuff. The remaining two wells were completed into the alluvium above the weathered tuff contact. These wells provide access for continuous water level measurement and water sampling. Data from these new wells will be used to determine changes in alluvial aquifer water storage, water quality sampling, and estimation of seepage into the unsaturated Bandelier Tuff below the alluvium. This report documents drilling activities and well completion logs for the water and mass balance study. These wells also provide critical new data for fourteen north-south vertical cross-sections constructed for the canyon alluvium.

McLin, S.G. [Los Alamos National Lab., NM (United States). Water Quality and Hydrology Group; Purtymun, W.D.; Swanton, A.S. [Los Alamos Technical Associates, NM (United States); Koch, R.J. [Science Applications International Corp., Los Alamos, NM (United States)

1997-10-01

118

Detailed evaluation of gas hydrate reservoir properties using JAPEX/JNOC/GSC Mallik 2L-38 gas hydrate research well downhole well-log displays  

USGS Publications Warehouse

The JAPEX/JNOC/GSC Mallik 2L-38 gas hydrate research well project was designed to investigate the occurrence of in situ natural gas hydrate in the Mallik area of the Mackenzie Delta of Canada. Because gas hydrate is unstable at surface pressure and temperature conditions, a major emphasis was placed on the downhole logging program to determine the in situ physical properties of the gas-hydrate-bearing sediments. Downhole logging tool strings deployed in the Mallik 2L-38 well included the Schlumberger Platform Express with a high resolution laterolog, Array Induction Imager Tool, Dipole Shear Sonic Imager, and a Fullbore Formation Microlmager. The downhole log data obtained from the log- and core-inferred gas-hydrate-bearing sedimentary interval (897.25-1109.5 m log depth) in the Mallik 2L-38 well is depicted in a series of well displays. Also shown are numerous reservoir parameters, including gas hydrate saturation and sediment porosity log traces, calculated from available downhole well-log and core data. The gas hydrate accumulation delineated by the Mallik 2L-38 well has been determined to contain as much as 4.15109 m3 of gas in the 1 km2 area surrounding the drill site.

Collett, T. S.

1999-01-01

119

MCNP (Monte Carlo Neutron Photon) capabilities for nuclear well logging calculations  

SciTech Connect

The Los Alamos Radiation Transport Code System (LARTCS) consists of state-of-the-art Monte Carlo and discrete ordinates transport codes and data libraries. The general-purpose continuous-energy Monte Carlo code MCNP (Monte Carlo Neutron Photon), part of the LARTCS, provides a computational predictive capability for many applications of interest to the nuclear well logging community. The generalized three-dimensional geometry of MCNP is well suited for borehole-tool models. SABRINA, another component of the LARTCS, is a graphics code that can be used to interactively create a complex MCNP geometry. Users can define many source and tally characteristics with standard MCNP features. The time-dependent capability of the code is essential when modeling pulsed sources. Problems with neutrons, photons, and electrons as either single particle or coupled particles can be calculated with MCNP. The physics of neutron and photon transport and interactions is modeled in detail using the latest available cross-section data. A rich collections of variance reduction features can greatly increase the efficiency of a calculation. MCNP is written in FORTRAN 77 and has been run on variety of computer systems from scientific workstations to supercomputers. The next production version of MCNP will include features such as continuous-energy electron transport and a multitasking option. Areas of ongoing research of interest to the well logging community include angle biasing, adaptive Monte Carlo, improved discrete ordinates capabilities, and discrete ordinates/Monte Carlo hybrid development. Los Alamos has requested approval by the Department of Energy to create a Radiation Transport Computational Facility under their User Facility Program to increase external interactions with industry, universities, and other government organizations. 21 refs.

Forster, R.A.; Little, R.C.; Briesmeister, J.F.

1989-01-01

120

The feasibility of well-logging measurements of arsenic levels using neutron-activation analysis  

USGS Publications Warehouse

Arsenic is an extremely toxic metal, which poses a significant problem in many mining environments. Arsenic contamination is also a major problem in ground and surface waters. A feasibility study was conducted to determine if neutron-activation analysis is a practical method of measuring in situ arsenic levels. The response of hypothetical well-logging tools to arsenic was simulated using a readily available Monte Carlo simulation code (MCNP). Simulations were made for probes with both hyperpure germanium (HPGe) and bismuth germanate (BGO) detectors using accelerator and isotopic neutron sources. Both sources produce similar results; however, the BGO detector is much more susceptible to spectral interference than the HPGe detector. Spectral interference from copper can preclude low-level arsenic measurements when using the BGO detector. Results show that a borehole probe could be built that would measure arsenic concentrations of 100 ppm by weight to an uncertainty of 50 ppm in about 15 min. ?? 2006 Elsevier Ltd. All rights reserved.

Oden, C. P.; Schweitzer, J. S.; McDowell, G. M.

2006-01-01

121

A measuring system for well logging attitude and a method of sensor calibration.  

PubMed

This paper proposes an approach for measuring the azimuth angle and tilt angle of underground drilling tools with a MEMS three-axis accelerometer and a three-axis fluxgate sensor. A mathematical model of well logging attitude angle is deduced based on combining space coordinate transformations and algebraic equations. In addition, a system implementation plan of the inclinometer is given in this paper, which features low cost, small volume and integration. Aiming at the sensor and assembly errors, this paper analyses the sources of errors, and establishes two mathematical models of errors and calculates related parameters to achieve sensor calibration. The results show that this scheme can obtain a stable and high precision azimuth angle and tilt angle of drilling tools, with the deviation of the former less than ±1.4° and the deviation of the latter less than ±0.1°. PMID:24859028

Ren, Yong; Wang, Yangdong; Wang, Mijian; Wu, Sheng; Wei, Biao

2014-01-01

122

A Measuring System for Well Logging Attitude and a Method of Sensor Calibration  

PubMed Central

This paper proposes an approach for measuring the azimuth angle and tilt angle of underground drilling tools with a MEMS three-axis accelerometer and a three-axis fluxgate sensor. A mathematical model of well logging attitude angle is deduced based on combining space coordinate transformations and algebraic equations. In addition, a system implementation plan of the inclinometer is given in this paper, which features low cost, small volume and integration. Aiming at the sensor and assembly errors, this paper analyses the sources of errors, and establishes two mathematical models of errors and calculates related parameters to achieve sensor calibration. The results show that this scheme can obtain a stable and high precision azimuth angle and tilt angle of drilling tools, with the deviation of the former less than ±1.4° and the deviation of the latter less than ±0.1°.

Ren, Yong; Wang, Yangdong; Wang, Mijian; Wu, Sheng; Wei, Biao

2014-01-01

123

Well log and seismic application in delineating CBM sweet spot in Berau Basin, East Kalimantan  

NASA Astrophysics Data System (ADS)

The study area is situated in the northern part of Berau Basin Northeast of Kalimantan. In the area Sajau Formation is the main coal bearing formation. The Sajau Coal were range from Lignite to sub bituminous, low ash content, and low to high cleated coal. Different with the conventional reservoir, coalbed methane reservoirs have sweet spot that are a function of structural/cleat and stratigraphy of the coal seam. The seismic data provides excellent image of faults and stratigraphy of coal seams are very much essential in CBM exploration as delineating the CBM sweet spot. Well log and acoustic impedance inversion can be applied in such a way to provide added insight to the coal distribution and cleat directions in coalbed-methane reservoirs. In this technique the property of acoustic impedance is of much importance in identifying different rock formations, which are associated with coal, and it has been successfully implemented.

Hamdani, Ahmad Helman; Hamdiana, Diana Putri; Ramadhan, Welly Ahmad

2013-09-01

124

Automated robotic equipment for ultrasonic inspection of pressurizer heater wells  

DOEpatents

A robotic device for remotely inspecting pressurizer heater wells is provided which has the advantages of quickly, precisely, and reliably acquiring data at reasonable cost while also reducing radiation exposure of an operator. The device comprises a prober assembly including a probe which enters a heater well, gathers data regarding the condition of the heater well and transmits a signal carrying that data; a mounting device for mounting the probe assembly at the opening of the heater well so that the probe can enter the heater well; a first motor mounted on the mounting device for providing movement of the probe assembly in an axial direction; and a second motor mounted on the mounting device for providing rotation of the probe assembly. This arrangement enables full inspection of the heater well to be carried out.

Nachbar, Henry D. (Ballston Lake, NY); DeRossi, Raymond S. (Amsterdam, NY); Mullins, Lawrence E. (Middle Grove, NY)

1993-01-01

125

Microbiologically influenced corrosion of oilfield producing well equipment  

SciTech Connect

This oilfield has been waterflooded for many years. After it was placed under polymer flood, severe corrosion was noted in the producing wells. This corrosion appears to be related to polymer breakthrough. Extensive analyses including various microbiological techniques strongly indicated bacterial involvement and a successful program of biocide treatments were begun on the wells.

Littmann, E.S.

1987-01-01

126

Correlation and complexity analysis of well logs via Lyapunov, Hurst, Lempel-Ziv and neural network algorithms  

NASA Astrophysics Data System (ADS)

Well logs produce a wealth of data that can be used to evaluate the production capacity of oil and gas fields. These data are usually concerned with depth series of petrophysical quantities such as the sonic transient time, gamma emission, deep induction resistivity, neutron porosity and bulk density. Here, we perform a correlation and complexity analysis of well log data from the Namorado’s school field using Lyapunov, Hurst, Lempel-Ziv and neural network algorithms. After identifying the most correlated and complex series, we demonstrate that well log data estimates can be confidently performed by neural network algorithms either to complete missing data or to infer complete well logs of a specific quantity.

Ferreira, R. B.; Vieira, V. M.; Gleria, Iram; Lyra, M. L.

2009-03-01

127

Integrated well-log, seismic, and biostratigraphic approach to sequence stratigraphy in Late Cenozoic expanded sections, Gulf of Mexico  

Microsoft Academic Search

Increased emphasis on well-log signatures and recognition criteria for stratigraphic sequence boundaries, systems tracts, and condensed sections in a sequence-stratigraphic context has enhanced facies interpretation and reservoir prediction capabilities. Integration of well logs with high-resolution biostratigraphy and paleobathymetry, high-quality seismic configuration data, and the latest eustatic cycle chart provides the best data base for sequence-stratigraphic analysis. This approach is particularly

R. M. Jr. Mitchum; J. B. Sangree; P. R. Vail; W. W. Wornar

1991-01-01

128

Tests Pits for Calibrating Well Logging Equipment in Fractured Hard-Rock Environment.  

National Technical Information Service (NTIS)

The calibration facility consists of three pits containing fine-grained granite, coarse-grained granite, and medium-grained metamorphosed granodiorite. Each pit contains large quarried blocks of rock that are 8 ft octagons and form a 20 ft stack. The bloc...

M. A. Mathews J. H. Scott C. M. LaDelfe

1985-01-01

129

High-resolution well-log derived dielectric properties of gas-hydrate-bearing sediments, Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope  

USGS Publications Warehouse

A dielectric logging tool, electromagnetic propagation tool (EPT), was deployed in 2007 in the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well (Mount Elbert Well), North Slope, Alaska. The measured dielectric properties in the Mount Elbert well, combined with density log measurements, result in a vertical high-resolution (cm-scale) estimate of gas hydrate saturation. Two hydrate-bearing sand reservoirs about 20 m thick were identified using the EPT log and exhibited gas-hydrate saturation estimates ranging from 45% to 85%. In hydrate-bearing zones where variation of hole size and oil-based mud invasion are minimal, EPT-based gas hydrate saturation estimates on average agree well with lower vertical resolution estimates from the nuclear magnetic resonance logs; however, saturation and porosity estimates based on EPT logs are not reliable in intervals with substantial variations in borehole diameter and oil-based invasion.EPT log interpretation reveals many thin-bedded layers at various depths, both above and below the thick continuous hydrate occurrences, which range from 30-cm to about 1-m thick. Such thin layers are not indicated in other well logs, or from the visual observation of core, with the exception of the image log recorded by the oil-base microimager. We also observe that EPT dielectric measurements can be used to accurately detect fine-scale changes in lithology and pore fluid properties of hydrate-bearing sediments where variation of hole size is minimal. EPT measurements may thus provide high-resolution in-situ hydrate saturation estimates for comparison and calibration with laboratory analysis. ?? 2010 Elsevier Ltd.

Sun, Y.; Goldberg, D.; Collett, T.; Hunter, R.

2011-01-01

130

Wireline log-based stratigraphy of flood basalts from the Lopra-1\\/1A well, Faroe Islands  

Microsoft Academic Search

The present study shows that it is possible to use conventional borehole logs to perform a detailed lithological\\/stratigraphical division of a column of subaerially extruded basalt. A stratigraphical divi- sion of the subaerial flood basalts penetrated by the Lopra-1\\/1A well has been carried out using new wire-line logging data measured in 1996 in the interval 200-2489 m depth. Resistivity data

Lars O. Boldreel

2006-01-01

131

30 CFR 250.614 - Well-control fluids, equipment, and operations.  

Code of Federal Regulations, 2013 CFR

...2 2013-07-01 2013-07-01 false Well-control fluids, equipment, and operations...OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Workover Operations § 250.614 Well-control fluids, equipment, and...

2013-07-01

132

30 CFR 250.514 - Well-control fluids, equipment, and operations.  

Code of Federal Regulations, 2013 CFR

...2 2013-07-01 2013-07-01 false Well-control fluids, equipment, and operations...OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion Operations § 250.514 Well-control fluids, equipment, and...

2013-07-01

133

Analysis of geophysical well logs obtained in the State 2-14 borehole, Salton Sea geothermal area, California  

USGS Publications Warehouse

A complete suite of conventional geophysical well logs was obtained in the upper part of a 3220-m-deep borehole drilled into geothermally altered alluvial sediments on the southeastern edge of the Salton Sea. Geophysical logs obtained in the State 2-14 borehole indicate that neutron porosity, gamma-gamma, and deep-induction logs provide useful information on lithologic trends with depth. The natural gamma log contains almost continuous, high-frequency fluctuations that obscure lithologic trends and that may be related to recent radioisotope redistribution and departure from radiometric equilibrium. Acoustic transit time logs give unrealistically low in situ compressional velocities ranging from 1.8 to 3.0 km/s, whereas acoustic waveform logs indicate that sediment compressional velocities range from less than 3.0 km/s shallower than 1000 m in depth to almost 5.0 km/s at depths greater than 2000 m. Analyses indicate that most log values lie between two lithologic end points: an electrically conductive claystone with moderate neutron porosity, but no effective porosity, and an electrically nonconductive, fully cemented siltstone that has small but finite porosity. -from Authors

Paillet, F. L.; Morin, R. H.

1988-01-01

134

Integrated reservoir characterization for unconventional reservoirs using seismic, microseismic and well log data  

NASA Astrophysics Data System (ADS)

This study is aimed at an improved understanding of unconventional reservoirs which include tight reservoirs (such as shale oil and gas plays), geothermal developments, etc. We provide a framework for improved fracture zone identification and mapping of the subsurface for a geothermal system by integrating data from different sources. The proposed ideas and methods were tested primarily on data obtained from North Brawley geothermal field and the Geysers geothermal field apart from synthetic datasets which were used to test new algorithms before actual application on the real datasets. The study has resulted in novel or improved algorithms for use at specific stages of data acquisition and analysis including improved phase detection technique for passive seismic (and teleseismic) data as well as optimization of passive seismic surveys for best possible processing results. The proposed workflow makes use of novel integration methods as a means of making best use of the available geophysical data for fracture characterization. The methodology incorporates soft computing tools such as hybrid neural networks (neuro-evolutionary algorithms) as well as geostatistical simulation techniques to improve the property estimates as well as overall characterization efficacy. The basic elements of the proposed characterization workflow involves using seismic and microseismic data to characterize structural and geomechanical features within the subsurface. We use passive seismic data to model geomechanical properties which are combined with other properties evaluated from seismic and well logs to derive both qualitative and quantitative fracture zone identifiers. The study has resulted in a broad framework highlighting a new technique for utilizing geophysical data (seismic and microseismic) for unconventional reservoir characterization. It provides an opportunity to optimally develop the resources in question by incorporating data from different sources and using their temporal and spatial variability as a means to better understand the reservoir behavior. As part of this study, we have developed the following elements which are discussed in the subsequent chapters: 1. An integrated characterization framework for unconventional settings with adaptable workflows for all stages of data processing, interpretation and analysis. 2. A novel autopicking workflow for noisy passive seismic data used for improved accuracy in event picking as well as for improved velocity model building. 3. Improved passive seismic survey design optimization framework for better data collection and improved property estimation. 4. Extensive post-stack seismic attribute studies incorporating robust schemes applicable in complex reservoir settings. 5. Uncertainty quantification and analysis to better quantify property estimates over and above the qualitative interpretations made and to validate observations independently with quantified uncertainties to prevent erroneous interpretations. 6. Property mapping from microseismic data including stress and anisotropic weakness estimates for integrated reservoir characterization and analysis. 7. Integration of results (seismic, microseismic and well logs) from analysis of individual data sets for integrated interpretation using predefined integration framework and soft computing tools.

Maity, Debotyam

135

Geophysical Logs of Selected Wells at the Diaz Chemical Superfund Site in the Village of Holley, New York, 2009  

USGS Publications Warehouse

Geophysical logs were collected and analyzed to define the bedrock fracture patterns and flow zones penetrated by three wells at the Diaz Chemical Superfund Site in the Village of Holley in Orleans County, New York. The work was conducted in December 2009 as part of the investigation of contamination by organic compounds in the shale, mudstone, and sandstone bedrock at the Site. The geophysical logs include natural-gamma, caliper, borehole image, fluid properties, and flowmeter data. The orientation of fractures in the boreholes was inferred from the log data and summarized in stereo and tadpole plots; when possible, the transmissivity and hydraulic head was also determined for fracture zones that were observed to be hydraulically active through the flowmeter logs. The data are intended, in part, for use in the remediation of the site.

Eckhardt, David A.V.; Anderson, J. Alton

2010-01-01

136

Application of Multi-rate Flowing Fluid Electric ConductivityLogging Method to Well DH-2, Tono Site, Japan  

SciTech Connect

The flowing fluid electric conductivity (FEC) logging method, wellbore fluid is replaced with de-ionized water, following which FEC profiles in the wellbore are measured at a series of times while the well is pumped at a constant rate. Locations were fluid enters the wellbore show peaks in the FEC logs, which may be analyzed to infer inflow strengths and salinities of permeable features intersected by the wellbore. In multi-rate flowing FEC logging, the flowing FEC logging method is repeated using two or more pumping rates, which enables the transmissivities and inherent pressure heads of these features to be estimated as well. We perform multi-rate FEC logging on a deep borehole in fractured granitic rock, using three different pumping rates. Results identify 19 hydraulically conducting fractures and indicate that transmissivity, pressure head, and salinity vary significantly among them. By using three pumping rates rather than the minimum number of two, we obtain an internal consistency check on the analysis that provides a measure of the uncertainty of the results. Good comparisons against static FEC profiles and against independent chemical, geological, and hydrogeological data have further enhanced confidence in the results of the multi-rate flowing FEC logging method.

Doughty, Christine; Takeuchi, Shinji; Amano, Kenji; Shimo, Michito; Tsang, Chin-Fu

2004-10-04

137

Permeability Estimation of Grosmont Formation, Alberta, Canada by Statistically Combining Well-logs and Core Measurements  

NASA Astrophysics Data System (ADS)

Permeability estimation in carbonate reservoirs is quite challenging since they are very heterogeneous. Moreover, the amount of core measurement data is commonly limited. In this paper, we present permeability maps for Grosmont formation in Canada with very limited permeability data, using bi-variated probability density function (porosity and permeability) conditioned to geological information. Grosmont formation consists of four units: Lower Grosmont (LG); Upper Grosmont (UG1); Upper Grosmont 2 (UG2); and Upper Grosmont 3 (UG3). From the previous studies, UG2 and UG3 are more promising reservoir units since they have larger porosity and permeability with vuggy pores and fractures by diagenesis (dolomitization and karstification). Thus, we applied our method to these two units. We first investigated core measurement data (porosity and permeability) and compared them to local geological aspects, such as the degree of diagenesis and vicinity of unconformity. Then we could divide the study area into 6 groups, and we established a bivariated probability density function (pdf) for each group and each unit (total of 12 pdfs) with core measurements of porosity and permeability. In the next step, we created porosity maps using well-log data for UG2 and UG3. The final step is to generate permeability maps for UG2 and UG3 by drawing a permeability value from the bivariated pdf conditioned to porosity. The final results show more realistic permeability maps for Grosmont formation when compared to conventional kriging results. Moreover, the strengths of this approach is (1) that it can use geological information and (2) that it can handle the variability of permeability, which can be naturally occurred in carbonate reservoirs. Acknowledgement: This work was supported by the Energy Resources R&D program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No. 2008RER11P0430302009).

Choi, J.; Keehm, Y.

2011-12-01

138

Drilling, construction, caliper-log, and specific-conductance data for well 3-3406-12, Twin Bridge Road deep monitor well, Oahu, Hawaii  

USGS Publications Warehouse

The Twin Bridge Road deep monitor well (State well number 3-3406-12) was drilled about 2,000 feet northeast of Weed Circle in the town of Haleiwa. The well is on agricultural land. The well penetrates through the freshwater lens and into the freshwater-saltwater transition zone of the Waialua ground-water area to an elevation of -596 feet below mean sea level. Well-construction data, logs of drilling notes, geologic descriptions for the samples, caliper-log, and specific-conductance data are presented for the well. The well is one of 12 exploratory wells drilled in the north- central Oahu area between July 1993 and May 1994 in cooperation with the Honolulu Board of Water Supply.

Presley, T. K.; Oki, D. S.

1996-01-01

139

Drilling, construction, caliper-log, and specific-conductance data for well 3-3604-01, Kawailoa deep monitor well, Oahu, Hawaii  

USGS Publications Warehouse

The Kawailoa deep monitor well (State well number 3-3604-01) was drilled about 1.9 miles east- northeast of the town of Haleiwa. The well is on agricultural land in the Kawailoa ground-water area. The well penetrates through the freshwater lens and into the freshwater-saltwater transition zone to an elevation of -392 feet below mean sea level. Well-construction data, logs of drilling notes, geologic descriptions for the samples, specific-conductance and caliper-log data are presented for the well. The well is one of 12 exploratory wells drilled in the north-central Oahu area between July 1993 and May 1994 in cooperation with the Honolulu Board of Water Supply.

Presley, T. K.; Oki, D. S.

1996-01-01

140

Brookian sequence well log correlation sections and occurrence of gas hydrates, north-central North Slope, Alaska  

USGS Publications Warehouse

Gas hydrates are naturally occurring crystalline, ice-like substances that consist of natural gas molecules trapped in a solid-water lattice. Because of the compact nature of their structure, hydrates can effectively store large volumes of gas and, consequently, have been identified as a potential unconventional energy source. First recognized to exist geologically in the 1960s, significant accumulations of gas hydrate have been found throughout the world. Gas hydrate occurrence is limited to environments such as permafrost regions and subsea sediments because of the pressure and temperature conditions required for their formation and stability. Permafrost-associated gas hydrate accumulations have been discovered in many regions of the Arctic, including Russia, Canada, and the North Slope of Alaska. Gas hydrate research has a long history in northern Alaska. This research includes the drilling, coring, and well log evaluation of two gas hydrate stratigraphic test wells and two resource assessments of gas hydrates on the Alaska North Slope. Building upon these previous investigations, this report provides a summary of the pertinent well log, gas hydrate, and stratigraphic data for key wells related to gas hydrate occurrence in the north-central North Slope. The data are presented in nine well log correlation sections with 122 selected wells to provide a regional context for gas hydrate accumulations and the relation of the accumulations to key stratigraphic horizons and to the base of the ice-bearing permafrost. Also included is a well log database that lists the location, available well logs, depths, and other pertinent information for each of the wells on the correlation section.

Lewis, Kristen A.; Collett, Timothy S.

2013-01-01

141

Possible New Well-Logging Tool Using Positron Annihilation Spectroscopy to Detect TOC in Source Rocks  

NASA Astrophysics Data System (ADS)

Possible New Well-Logging Tool Using Positron Annihilation Spectroscopy to Detect Total Organic Carbon (TOC) in Source Rocks PATTERSON, C., Department of Geology, Department of Physics, Texas Christian University, QUARLES, C.A., Department of Physics, Texas Christian University, Fort Worth, Texas, BREYER, J.A., Department of Geology, Texas Christian University, Fort, Worth, Texas. The positron produces two gamma rays upon annihilation with an electron. Depending on the momentum of the electron, the two resulting photons are shifted from the initial electron rest mass energy by the Doppler effect. We measure the distribution of gamma ray energies produced by annihilation on a petroleum source rock core. Core from the Mitchell Energy well T.P. Sims 2 of the Barnett Shale located in Wise County, Texas, is under study. Apparatus for the experiment consists of an Ortec Ge detector. The source used for the experiment is Ge68, which undergoes beta decay and produces the positrons that penetrate the core. It is placed on the middle of the core and covered with a small, annealed NiCu plate to prevent unnecessary background from the positrons annihilating with electrons other than in the core. Distance between the source and the detector is fixed at 6.75 inches. Measurements were made in specific locations at 2 inch increments for approximately an hour and a half where the predetermined Total Organic Carbon (TOC) values were made. Future studies involve an overall correlation of the core between experimental readings and TOC, including corrections for changes in grain size and lithology. Additional research has shown no distinct correlation between grain size and distribution of energies across the targeted spectrum. Additional corrections should be made for the decay in activity of the source. Future research also includes the determination for optimum time and distance for the source from the core. A long-term goal for the experiment is to develop an effective down-hole tool to determine TOC in potential source rocks, thereby minimizing time coring and geochemical analysis.

Patterson, Casey; Quarles, C. A.; Breyer, J. A.

2001-10-01

142

Use of well logs and core data to assess the sequence stratigraphic distribution of organic-rich rocks  

Microsoft Academic Search

Application of a well log technique for routine profiling of total organic carbon (TOC) in source rocks has revealed that patterns in the vertical distribution of TOC commonly occur. Marine source rocks frequently are composed of one or more units with the highest TOC values near the base. These units coalesce in a seaward direction and form a relatively smooth

S. Creaney; J. Allan; Q. R. Passey

1991-01-01

143

Neural network prediction of carbonate lithofacies from well logs, Big Bow and Sand Arroyo Creek fields, Southwest Kansas  

USGS Publications Warehouse

In the Hugoton Embayment of southwestern Kansas, St. Louis Limestone reservoirs have relatively low recovery efficiencies, attributed to the heterogeneous nature of the oolitic deposits. This study establishes quantitative relationships between digital well logs and core description data, and applies these relationships in a probabilistic sense to predict lithofacies in 90 uncored wells across the Big Bow and Sand Arroyo Creek fields. In 10 wells, a single hidden-layer neural network based on digital well logs and core described lithofacies of the limestone depositional texture was used to train and establish a non-linear relationship between lithofacies assignments from detailed core descriptions and selected log curves. Neural network models were optimized by selecting six predictor variables and automated cross-validation with neural network parameters and then used to predict lithofacies on the whole data set of the 2023 half-foot intervals from the 10 cored wells with the selected network size of 35 and a damping parameter of 0.01. Predicted lithofacies results compared to actual lithofacies displays absolute accuracies of 70.37-90.82%. Incorporating adjoining lithofacies, within-one lithofacies improves accuracy slightly (93.72%). Digital logs from uncored wells were batch processed to predict lithofacies and probabilities related to each lithofacies at half-foot resolution corresponding to log units. The results were used to construct interpolated cross-sections and useful depositional patterns of St. Louis lithofacies were illustrated, e.g., the concentration of oolitic deposits (including lithofacies 5 and 6) along local highs and the relative dominance of quartz-rich carbonate grainstone (lithofacies 1) in the zones A and B of the St. Louis Limestone. Neural network techniques are applicable to other complex reservoirs, in which facies geometry and distribution are the key factors controlling heterogeneity and distribution of rock properties. Future work involves extension of the neural network to predict reservoir properties, and construction of three-dimensional geo-models. ?? 2005 Elsevier Ltd. All rights reserved.

Qi, L.; Carr, T. R.

2006-01-01

144

Comparison between different well logging tools for the determination of the electrical conductivity of near-surface limestone site formations  

NASA Astrophysics Data System (ADS)

The determination of the electrical conductivity of rocks, measured in boreholes, has important applications. For example, electrical logs are useful to perform well-to-well correlations (when gamma-ray data do not have a sufficient quality) and thus, are an important information for the construction of 3D structural models. These logs give also indirect information on the rock saturation, clay content, etc., and thus are useful for the petrologic characterization of geological media. Galvanic resistivity tolls ("normal arrays", "laterolog", etc.), consisting in several metallic electrodes through which current is transmitted or the resulting voltage differences are measured, are efficient, easy to calibrate, fast and cheap to use and provide logs with a good vertical resolution. Nevertheless, they can only be used in wells filled with water or mud and thus, can not be used in unsaturated zones. This is a real limitation for near-surface characterization in limestone site where water tables are often deep. Electromagnetic induction tools (based on the generation of an alternating magnetic field, which induces current flow in the earth, and the measurement of the resulting magnetic field) can work in dry wells, but are more difficult to calibrate and provide data with a lower vertical resolution. The use of borehole radar (with an adapted unusual acquisition protocol), could be an interesting alternative, even in medium in which radar signals are strongly attenuated: we only use the direct waves in configuration where antennas are close one from the other. This tool can also provide logs of a second parameter: the dielectric permittivity. Our study compares results obtained which these different approaches. Data was recorded in a reference well on a limestone test-site ("Medecin Hill", Centre d’Etude de Cadarache, 13108 St. Paul lez Durance, France). Well logs are also compared to laboratory measurements within the frequency range [1 kHz - 200 MHz] carried to determine the electric conductivity and the dielectric permittivity of centimetric samples.

Hollender, F.; Delarche, S.; Sénéchal, G.

2003-04-01

145

In-situ gas hydrate hydrate saturation estimated from various well logs at the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope  

USGS Publications Warehouse

In 2006, the U.S. Geological Survey (USGS) completed detailed analysis and interpretation of available 2-D and 3-D seismic data and proposed a viable method for identifying sub-permafrost gas hydrate prospects within the gas hydrate stability zone in the Milne Point area of northern Alaska. To validate the predictions of the USGS and to acquire critical reservoir data needed to develop a long-term production testing program, a well was drilled at the Mount Elbert prospect in February, 2007. Numerous well log data and cores were acquired to estimate in-situ gas hydrate saturations and reservoir properties.Gas hydrate saturations were estimated from various well logs such as nuclear magnetic resonance (NMR), P- and S-wave velocity, and electrical resistivity logs along with pore-water salinity. Gas hydrate saturations from the NMR log agree well with those estimated from P- and S-wave velocity data. Because of the low salinity of the connate water and the low formation temperature, the resistivity of connate water is comparable to that of shale. Therefore, the effect of clay should be accounted for to accurately estimate gas hydrate saturations from the resistivity data. Two highly gas hydrate-saturated intervals are identified - an upper ???43 ft zone with an average gas hydrate saturation of 54% and a lower ???53 ft zone with an average gas hydrate saturation of 50%; both zones reach a maximum of about 75% saturation. ?? 2009.

Lee, M. W.; Collett, T. S.

2011-01-01

146

Review of well-logging techniques. [For use in remedial action programs  

Microsoft Academic Search

A literature review has been conducted to determine whether suitable borehole-logging techniques exist for the measurement of gamma-ray-emitting elements using downhole detectors. Most of the methods that have been used for the last 30 years by the uranium-exploration industry involve passive gamma-ray measurement techniques utilizing NaI(Tl) and, occasionally, intrinsic germanium detectors. Parameters the industry has had to consider in calibrating

K. B. Olsen; J. A. Young; V. W. Thomas

1983-01-01

147

Recognition of hydrocarbon expulsion using well logs: Bakken Formation, Williston Basin  

Microsoft Academic Search

The Upper Mississippian-Lower Devonian Bakken Formation forms a source\\/carrier\\/reservoir system in the Williston basin. Hydrocarbon expulsion within the Bakken has been identified by overlaying sonic and resistivity logs. Typically, these curves track in organically lean, water-saturated mudrocks because both respond mainly to porosity; however, in thermally mature organic-rich rocks and hydrocarbon reservoirs or carrier beds, the curves separate due to

R. Cunningham; F. B. Zelt; S. R. Morgan; Q. R. Passey; P. D. Snavely; R. L. Webster

1990-01-01

148

A computer program for borehole compensation of dual-detector density well logs  

USGS Publications Warehouse

The computer program described in this report was developed for applying a borehole-rugosity and mudcake compensation algorithm to dual-density logs using the following information: the water level in the drill hole, hole diameter (from a caliper log if available, or the nominal drill diameter if not), and the two gamma-ray count rate logs from the near and far detectors of the density probe. The equations that represent the compensation algorithm and the calibration of the two detectors (for converting countrate or density) were derived specifically for a probe manufactured by Comprobe Inc. (5.4 cm O.D. dual-density-caliper); they are not applicable to other probes. However, equivalent calibration and compensation equations can be empirically determined for any other similar two-detector density probes and substituted in the computer program listed in this report. * Use of brand names in this report does not necessarily constitute endorsement by the U.S. Geological Survey.

Scott, James Henry

1978-01-01

149

Geophysical natural ?-ray well logging and spectrometric signatures of south AL-Abter phosphatic deposits in Syria  

Microsoft Academic Search

A combination of several exploration techniques was carried out in AL-Abter region, aiming at outlining the main characteristics of the phosphatic layers in this region. The techniques used in this research are natural ?-ray well logging, gamma and alpha-spectrometry. It is shown that uranium concentrations in the samples taken from the wells studied vary between 42.8 and 112.5 ppm with

J Asfahani; A Abdul-Hadi

2001-01-01

150

Choosing the averaging interval when calculating primary reflection coefficients from well logs  

SciTech Connect

Most seismic data is processed using a sample interval of 4 ms two-way time (twt). The study of the statistical properties of primary reflection coefficients showed that the power spectrum of primaries can change noticeably when the logs are averaged over blocks of 0.5, 1 and 2 ms twt (block-averaging). What is a suitable block-averaging interval for producing broadband synthetics, and in particular how should the power spectrum of primaries be constructed when it is to be used to correct 4 ms sampled deconvolved seismic data for the effects of coloured primary reflectivity. In this paper the authors show that for a typical sonic log, a block-averaging interval of 1 ms twt should satisfy some important requirements. Firstly, it is demonstrated that if the reflection coefficients in an interval are not too large the effect of all the reflection impulses can be represented by another much sparser set at intervals of ..delta..t twt. The coefficient amplitudes are given by the differences in the logarithmic acoustic impedances, thus justifying block-averaging. However, a condition for this to hold up to the aliasing (Nyquist) frequency is that ..delta..t takes a maximum value of about 1 ms twt. Secondly, an event on a log should be represented in the seismic data. For this the acoustic impedance contrast must have sufficient lateral extent or continuity. By making some tentative suggestions on the relation between continuity and bed-thickness, a bed-thickness requirement of 0.15 m or more is obtained. Combining this requirement with the maximum number of beds allowable in an interval in order that multiple reflections do not contribute significantly to the reflections in the interval, again suggests a value of about 1 ms for the block-averaging interval.

Walden, A.T.; Hosken, J.W.J.

1988-11-01

151

A Generalized Approach for the Interpretation of Geophysical Well Logs in Ground-Water Studies - Theory and Application  

USGS Publications Warehouse

Quantitative analysis of geophysical logs in ground-water studies often involves at least as broad a range of applications and variation in lithology as is typically encountered in petroleum exploration, making such logs difficult to calibrate and complicating inversion problem formulation. At the same time, data inversion and analysis depend on inversion model formulation and refinement, so that log interpretation cannot be deferred to a geophysical log specialist unless active involvement with interpretation can be maintained by such an expert over the lifetime of the project. We propose a generalized log-interpretation procedure designed to guide hydrogeologists in the interpretation of geophysical logs, and in the integration of log data into ground-water models that may be systematically refined and improved in an iterative way. The procedure is designed to maximize the effective use of three primary contributions from geophysical logs: (1) The continuous depth scale of the measurements along the well bore; (2) The in situ measurement of lithologic properties and the correlation with hydraulic properties of the formations over a finite sample volume; and (3) Multiple independent measurements that can potentially be inverted for multiple physical or hydraulic properties of interest. The approach is formulated in the context of geophysical inversion theory, and is designed to be interfaced with surface geophysical soundings and conventional hydraulic testing. The step-by-step procedures given in our generalized interpretation and inversion technique are based on both qualitative analysis designed to assist formulation of the interpretation model, and quantitative analysis used to assign numerical values to model parameters. The approach bases a decision as to whether quantitative inversion is statistically warranted by formulating an over-determined inversion. If no such inversion is consistent with the inversion model, quantitative inversion is judged not possible with the given data set. Additional statistical criteria such as the statistical significance of regressions are used to guide the subsequent calibration of geophysical data in terms of hydraulic variables in those situations where quantitative data inversion is considered appropriate.

Paillet, F. L.; Crowder, R. E.

1996-01-01

152

Borehole Geophysical Logging of Water-Supply Wells in the Piedmont, Blue Ridge, and Valley and Ridge, Georgia  

USGS Publications Warehouse

Crystalline and carbonate-rock aquifers in northern Georgia provide water to an ever-increasing number of private and public wells in the region. Understanding the depth and yield of water-bearing zones in such wells is crucial for the development and long-term sustainability of ground-water resources and for keeping wells in good operating condition. Portable geophysical logging units are now widely available and have greatly increased the ability of geoscientists to obtain subsurface information from water wells.

Geological Survey (U.S.)

2007-01-01

153

Sequence stratigraphy of the Jurassic: New data from the Paris-London basin compiled on well logs  

SciTech Connect

A sequence stratigraphic analysis of the Jurassic sedimentary succession in Paris basin is derived from an integration of subsurface log correlations, field observations, and reinterpretations of field descriptions. The analysis is presented on two log sections, one crossing the basin from northeast to southwest and the other from northwest to southeast (approximately 80 logs). A vast quantity of field data, collected all around the Parsi basin (English Dorset, French Normandy, Manche, Ardennes, Lorraine, Bourgogne) allowed the sequences and system tracts boundaries to be traced and dated at the same time or prior to being recognized on well log data. In comparison with the Haq et al. 1987 cycle chart, 16 new sequences have been added: three for the Lias, seven for the Dogger, and six for the Malm. Occasionally, ages of some of the already recognized sequences boundaries have been slightly modified to fit new biostratal data. These biostratal data were usually at the scale of the ammonite sub-zone and the actual give ages all tie with the 1987 Haq et al. chart time scale.

Ponsot, C.M.; Vail, P.R. (Rice Univ., Houston, TX (United States))

1991-03-01

154

Well log and seismic character of tertiary terumbu carbonate, South China Sea, Indonesia  

SciTech Connect

The Esso Exploration and Production Inc. Natuna DAlpha block lies approximately 125 mi (200 km) northeast of Natuna Island in the Indonesian portion of the South China Sea. The block contains a large Miocene platform carbonate complex called the L-structure. The Terumbu Formation L-structure, situated in front of and isolated from a much larger carbonate shelf, is similar to the carbonate atolls developed in front of the barrier-reef complex offshore of Belize. The lower platform and upper platform have a similar log character. The detrital facies is composed of fore-reef talus, pelagic, and hemipelagic carbonates. By mapping the Terumbu carbonate facies, the growth history of the L-structure is revealed.

May, J.A.

1985-09-01

155

A new intense neutron generator and high-resolution detector for well logging applications  

SciTech Connect

Advances in both ion source and gamma-ray detector technology at LBNL are being used to develop a new high-sensitivity neutron logging instrument. Up to 37 mA of current per 10-20 {mu}s pulse, 80-95% D{sup +}, has been produced by a 2 inch diameter pulsed multicusp ion source. A D-T neutron flux of 10{sup 9}-10{sup 10} n/s is projected from this data. CdZnTe is being developed as a possible gamma-ray detector because of its potential for good energy resolution and efficiency, and ability to operate at room temperature. 3-D time-dependent Monte Carlo calculations show the utility of this system for locating contaminants, especially chlorine-containing solvents, at remediation sites.

Celata, C.M.; Amman, M.; Donahue, R. [and others

1996-10-01

156

Well-log based prediction of thermal conductivity of sedimentary successions: a case study from the North German Basin  

NASA Astrophysics Data System (ADS)

Data on rock thermal conductivity (TC) are important for the quantification of the subsurface temperature regime and for the determination of heat flow. If drill core is not retrieved from boreholes and thus no laboratory measurement of TC can be made, other methods are desired to determine TC. One of these methods is the prediction of TC from well logs. We have examined the relationships between TC and standard well-log data (gamma ray, density, sonic interval transit time, hydrogen index and photoelectric factor) by a theoretical analysis and by using real subsurface data from four boreholes of the North German Basin. The theoretical approach comprised the calculation of TC from well-log response values for artificial sets of mineral assemblages consisting of variable contents of 15 rock-forming minerals typical for sedimentary rocks. The analysis shows different correlation trends between TC and the theoretical well-log response in dependence on the mineral content, affecting the rock matrix TC, and on porosity. The analysis suggests the development of empirical equations for the prediction of matrix TC separately for different groups of sedimentary rocks. The most valuable input parameters are the volume fraction of shale, the matrix hydrogen index and the matrix density. The error of matrix TC prediction is on the order of 4.2 ± 3.2 per cent (carbonates), 7.0 ± 5.6 per cent (evaporites), and 11.4 ± 9.1 per cent (clastic rocks). From the subsurface data, comprising measured TC values (n = 1755) and well-log data, four prediction equations for bulk TC were developed resembling different lithological compositions. The most valuable input parameters for these predictions are the volume fraction of shale, the hydrogen index and the sonic interval transit time. The equations predict TC with an average error between 5.5 ± 4.1 per cent (clean sandstones of low porosity; Middle Buntsandstein), 8.9 ± 5.4 per cent (interbedding of sandstone, silt- and claystones; Wealden), and 9.4 ± 11 per cent (shaly sandstones; Stuttgart Fm.). An equation including all clastic rock data yields an average error of 11 ± 10 per cent. The subsurface data set also was used to validate the prediction equation for matrix TC established for clastic rocks. Comparison of bulk TC, computed from the matrix TC values and well-log porosity according to the geometric-mean model, to measured bulk TC results in an accuracy <15 per cent. A validation of the TC prediction at borehole scale by comparison of measured temperature logs and modeled temperature logs (based on the site-specific surface heat flow and the predicted TC) shows an excellent agreement in temperature. Interval temperature gradients vary on average by <3 K km-1 and predicted compared to measured absolute temperature fitted with an accuracy <5 per cent. Compared to previously published TC prediction approaches, the developed matrix and bulk TC prediction equations show significantly higher prediction accuracy. Bulk TC ranging from 1.5 to 5.5 W (m K)-1 is always predicted with an average error <10 per cent relative to average errors between 15 and 35 per cent resulting from the application to our data set of the most suitable methods from literature.

Fuchs, Sven; Förster, Andrea

2014-01-01

157

Review of well-logging techniques. [For use in remedial action programs  

SciTech Connect

A literature review has been conducted to determine whether suitable borehole-logging techniques exist for the measurement of gamma-ray-emitting elements using downhole detectors. Most of the methods that have been used for the last 30 years by the uranium-exploration industry involve passive gamma-ray measurement techniques utilizing NaI(Tl) and, occasionally, intrinsic germanium detectors. Parameters the industry has had to consider in calibrating these detectors are variations in (1) casing material and thickness, (2) water in the borehole, (3) hole diameter, (4) disequilibrium between uranium and its daughters in the ore zone, (5) spatial distribution of the radioactive material, and (6) dead time of the analyzer. The methods they have used to address these variable parameters appear to be applicable to remedial action programs. The techniques that have been used for the measurement of subsurface radium concentration by DOE during the engineering assessment of UMTRAP/FUSRAP sites and by NRC at one remedial action site will be described in this report.

Olsen, K.B.; Young, J.A.; Thomas, V.W.

1983-04-01

158

Well-log seismic sequence stratigraphy of Aruba and its application to the hydrocarbon exploration in the Caribbean Area  

SciTech Connect

Several wells have recently been drilled in offshore Aruba approximately 12 degrees NOrth Latitude and 70 degrees West Longitude, just north of the Westernpart of Venezuela, South Central Caribbean. One of the wells, the Oxy Chuchubi No. 1 well penetrated a largely carbonate section that ranged in age from early Pliocene to early Oligocene to late Eocene at its total depth of 9,210 feet. High resolution biostratigraphy of benthic and planktonic foraminifers and calcareous nannofossils provided the abundance and diversity histograms necessary to recognized a series of maximum flooding surface condensed sections (MSF). Fourteen maximum flooding surfaces within the MFS condensed sections were identified on the well log and dated using the planktonic foraminifers and calcareous nannofossils. These maximum flooding surfaces range in age from 4.0 Ma or possibly 36.5 Ma. The paleobathymetry varies from middle to outer neritic in the upper portion of the well to lower bathyal to abyssal in the lower portion of the well. Fourteen third order sequences and their systems tracts were identified and annotated on a well log. These sequences were correlated with the Global Cycle Chart of Hag, 1987. The sequence stratigraphy provides a means of chronostratigraphic correlation to Venezuela and provides a direct tie to the geological history and hydrocarbon potential of the area.

Wornardt, W.W. (Micro-Strat Inc., Houston, TX (United States)); Vail, P.R. (Rice Univ., Houston, TX (United States))

1993-02-01

159

Characterization of injection wells in a fractured reservoir using PTS logs, Steamboat Hills Geothermal Field, Nevada, USA  

SciTech Connect

The Steamboat Hills Geothermal Field in northwestern Nevada, about 15 km south of Reno, is a shallow (150m to 825m) moderate temperature (155 C to 168 C) liquid-dominated geothermal reservoir situated in highly-fractured granodiorite. Three injection wells were drilled and completed in granodiorite to dispose of spent geothermal fluids from the Steamboat II and III power plants (a 30 MW air-cooled binary-type facility). Injection wells were targeted to depths below 300m to inject spent fluids below producing fractures. First, quasi-static downhole pressure-temperature-spinner (PTS) logs were obtained. Then, the three wells were injection-tested using fluids between 80 C and 106 C at rates from 70 kg/s to 200 kg/s. PTS logs were run both up and down the wells during these injection tests. These PTS surveys have delineated the subsurface fracture zones which will accept fluid. The relative injectivity of the wells was also established. Shut-in interzonal flow within the wells was identified and characterized.

Goranson, Colin; Combs, Jim

1995-01-26

160

An Improved Simulation for Interpreting Temperature Logs in Water Injection Wells  

Microsoft Academic Search

In this paper, the authors present an improved injection-well temperature simulator of the digital computer variety. This simulator offers an advantage over previous simulators in that wellbore-water heat transfer is modeled both before and after shut-in of the well. This capability allowed them to investigate possible solutions to the problem of lost profile definition in mature injection wells. They have

John Fagley; H. Fogler; R. S. Millhone

1982-01-01

161

Prediction of compressional wave velocity by an artificial neural network using some conventional well logs in a carbonate reservoir  

NASA Astrophysics Data System (ADS)

As vital records for the upstream petroleum industry, compressional-wave (Vp) data provide important information for reservoir exploration and development activities. Due to the different nature and behaviour of the influencing parameters, more complex nonlinearity exists for Vp modelling purposes. Therefore, formulating a prediction tool that can accurately estimate the lacking log data, such as Vp, is of prime importance. Therefore, an attempt has been made to develop a prediction model for Vp as a function of some conventional well logs by using an artificial neural network (ANN). The obtained results are compared to those of multiple linear regression (MLR) models. A total of 2156 data points from a giant Middle Eastern carbonate reservoir, derived from a conventional wire line and a dipole sonic imager log were used in this study. The efficiency of the employed approach, quantified in terms of the mean squared error correlation coefficient (R-square), and prediction efficiency error, is evaluated through simulation and the results are presented. The result showed that an ANN outperforms MLRs and was found to be more robust and reliable.

Zoveidavianpoor, Mansoor; Samsuri, Ariffin; Shadizadeh, Seyed Reza

2013-08-01

162

Gamma well-logging in the Old Burial Ground of the Savannah River Site  

SciTech Connect

Results are given sequentially by well in the appendix; total is 44 wells. Overall, the 1994 results do not suggest that any significant changes in activity or location have occurred since the 1980 measurements. Depths and magnitudes of plume activities for 1980 and 1994 are compared.

Winn, W.G.; Hofstetter, K.J.; MacMurdo, K.W. [and others

1995-01-01

163

Well logging apparatus with replaceable sensor carrying insulating sleeve disposed in rotation restrained position around a drill string  

Microsoft Academic Search

A replaceable insulating sleeve is disposed around the lower end of a drill string used in drilling a well. The sleeve is restrained from rotating relative to the drill string, but can be released and quickly slipped off the drill string in the field to permit rapid replacement if damaged, or if alternate equipment is required. The sleeve carries sensing

J. D. Jeter; H. S. More

1985-01-01

164

Realtime logging  

SciTech Connect

This article reports that measurement-while-drilling (MWD) logging services have become an important new source of drilling and geological information on wildcats and some development wells. Sensors located within the bottomhole assembly, barely a few feet above the bit, make measurements on the formation, the borehole and the drill string itself. The MWD measurements are electronically processed and stored in the logging tool downhole. Simple MWD logging systems must wait until after tripping out of the hole for the MWD data to be downloaded from the logging tool to a surface computer in order for logs to be produced. This method is acceptable for some formation evaluation problems. But when well control, directional or completion decisions must be made, the benefit of MWD logging data is obtained only if the downhole measurements are available to the engineer in realtime.

Whittaker, A.; Kashuba, M.J.

1987-01-01

165

Closed-loop flow test Miravalles Geothermal Field well log results  

SciTech Connect

The Instituto Costarricense de Electricidad (ICE) conducted a closed-loop flow test in the Miravalles Geothermal Field. The closed-loop test was started in May and ran through August of 1990. The effluent from the production well PG-11 was carried by a pipeline through a monitor station to the injection well PG-2. Before starting the long-term flow test in May, cold-water injection experiments were performed in each well to determine the pressure and temperature response. A series of downhole measurements were made in each well to obtain background information. The downhole measurements were repeated in August just before terminating the flow test to evaluate the results.

Dennis, B.; Eden, G.; Lawton, R.

1992-10-01

166

Closed-loop flow test Miravalles Geothermal Field well log results  

SciTech Connect

The Instituto Costarricense de Electricidad (ICE) conducted a closed-loop flow test in the Miravalles Geothermal Field. The closed-loop test was started in May and ran through August of 1990. The effluent from the production well PG-11 was carried by a pipeline through a monitor station to the injection well PG-2. Before starting the long-term flow test in May, cold-water injection experiments were performed in each well to determine the pressure and temperature response. A series of downhole measurements were made in each well to obtain background information. The downhole measurements were repeated in August just before terminating the flow test to evaluate the results.

Dennis, B.; Eden, G.; Lawton, R.

1992-01-01

167

Large surface warming in circumpolar regions of the northern hemisphere evidenced by inversion of well temperature logs  

NASA Astrophysics Data System (ADS)

Northern Canadian and Alaskan (60-82 deg. N) precise well temperature logs show evidence of extensive surface temperature (ST) warming beginning in the 18th - 20th centuries. The method of functional space inversion (FSI) applied to temperature logs in northern Canada regions show a warming of 1-4 C. Similar warming amplitudes are evident from FSI inversions of Alaskan wells and less numerous Eurasian wells. Analysis of 150 FSI derived warming histories for the circumpolar areas points to ST warming magnitudes approximately 0.9 C higher than those of proxy climate records based change (Arctic-wide summer - weighted annual temperature change of 0.5 C in the last four centuries; Overpeck et al., 1997; Osborn and Briffa, 2002). When the well temperature based warming magnitudes are combined in latitudinal groups (70 - 82 deg. N, 60 - 70 deg. N and 50- 60 deg. N classes) there is no evidence of significant north to south decrease in the amplitude of warming over the last 2 centuries. The warming south of 50 deg. N is significantly less than that observed to the north.

Majorowicz, J.; Safanda, J.; Skinner, W.

2003-04-01

168

Collaborative multi-agent rock facies classification from wireline well log data  

Microsoft Academic Search

Gas and oil reservoirs have been the focus of modeling efforts for decades as an attempt to locate zones with high volumes. Certain subsurface layers and layer sequences, such as those containing shale, are known to be impermeable to gas and\\/or liquid. Oil and natural gas then become trapped by these layers, making it possible to drill wells to reach

Christopher M. Gifford; Arvin Agah

2010-01-01

169

Tangafric: a software for the estimation of textural and hydraulic properties in shallow aquifers from well logs in Senegal and Guinea  

NASA Astrophysics Data System (ADS)

Background In order to increase access to drinking water in Africa there is more and more interest in the promotion of manual drilling techniques, without need of expensive drilling equipment, but they can be applied only in those areas with suitable hydrogeological conditions: thick layers of unconsolidated sediments and shallow groundwater level. Mapping of suitable zones for manual drilling at national level in Africa is a crucial activity and local institutions and UNICEF are implementing specific programs for its promotion, but the limitation in available data concerning shallow hydrogeological aquifers are limited. The research has been developed in the project "Use of remote sensing and terrain modeling to identify suitable zones for manual drilling in Africa and support low cost water supply", within the scientific cooperation between the University of Milano-Bicocca, Universite' Cheick Anta Diop (Dakar Senegal) , SNAPE - Service Nationale de Points d'Eau (Conakry Guinea), UNICEF Senegal and UNICEF Guinea. The project is funded by NERC (National Environmental Research Council, UK). Objective of the research: The presented work is only the starting point of the project aiming to elaborate an automatic procedures to manage and improve the existing database of borehole logs in Senegal and Guinea for the interpretation of shallow hydrogeological conditions and identification of suitable zones for manual drilling, in two pilot areas: Louga (Northwestern Senegal) and Faranah/Kankan (Eastern Guinea). Within the objective of the project is also considered the integration of Remote Sensing to support hydrogeological interpretation, especially where borehole logs are not present. Methodology Focus is to create a hydrogeological database, TANGAFRIC, to organize, codify and elaborate hydrogeological data. The metodology derives from the software TANGRAM (www.tangram.samit.unimib.it) produced by the University of Milano Bicocca, with innovative aspect of stratigraphic data codification, quantification and processing, connected to a hydraulic conductivity value associated to each primary lithology. Results Starting from the database of borehole logs available at national level in Senegal and Guinea (about 1400 borehole logs in Senegal and 800 in Guinea, with 20000 definitions), their structure and information have been compared and a new common database has been set up; it has a consistent structure with the structure of existing national database and data can be easily imported and exported. From this joint, the new software TANGAFRIC has been created with different purposes: -to organize in the same way wells data, since the two countries have different administrative divisions (ID code, name of village, district, regions, coordinates); -to add new wells data, not existing in the previous databases; -to codify the stratigraphic layer of each well logs with a 5-digit alphanumeric codes, using a list of categories describing texture, status and color or each layers, identified from the most recurrent lithological classes and attributes; -to attribute a specific value of hydraulic conductivity to each texture, from well data, field pumping test, bibliographic review. TANGAFRIC includes one module for data input and a second module to process the data, and extract specific parameters concerning mean texture, hydraulic conductivity and transmissivity in selected depth ranges. This is made possible by attributing a weight to the digits of the code for textures. The program calculates the percentage of the chosen lithology, as related to each individual layer, and also a weighted average of hydraulic conductivity. It has been possible to produce maps showing the distribution of main texture classes, thickness of saturated unconsolidated sediments and expected transmissivity. Furthermore, these parameters have been used to estimate the suitability for manual drilling under the hydrogeological coniditions described in each borehole logs.

Fussi, Fabio; Bonomi, Tullia; Fava, Francesco; Hamidou, Barry; Hamidou Khane, Cheikh; Faye, Gayane; Wade, Souleye; Colombo, Roberto

2014-05-01

170

Review of surface-equipment requirements for geothermal-well stimulation. Geothermal-reservoir well-stimulation program  

SciTech Connect

A summary of stimulation equipment available to geothermal industry is presented and some modifications from which it could benefit are discussed. Equipment requirements for hydraulic fracturing, acid fracturing, acidizing, and other chemical treatments are included. Designs for the following are reviewed: equipment for premixing and storing treatment fluids, proppant handling equipment, pump trucks, special equipment for foam fracturing, intensifier pumps, manifolding, and monitoring and control devices.

Not Available

1982-02-01

171

Development of downhole equipment for Beatrice electrical submersible pump (ESP) wells 1981-1985  

SciTech Connect

The Beatrice Field in the North Sea relies exclusively for production on artificial lift, using electrical submersible pumps (ESP's). Beatrice came on stream during September, 1981 from 3 wells on the 'A' platform. 'B' and 'C' platforms were completed during 1984/1985 and there are now 22 production wells, each with an ESP and 12 water injection wells for pressure maintenance. The ESP installation performance on Beatrice has progressively improved in the pumping of mono-phasic fluids. Average pump life (excluding non-start failures, which are counted at completion installation failures) over the operating period has steadily increased and for the last year has been running at approximately 10 months. Average installation and retrieval times for equipment have steadily decreased. Both improvements can be largely attributed to equipment developments that have taken place in the UK. The principal developments described in this paper are: Electrical developments for downhole power transmission systems; Connectorless packer penetrations; Metal cable protectors; wireline adaptors.

Brown, J.K.; Bills, D.

1985-01-01

172

Applying Backus averaging for deriving seismic anisotropy of a long-wavelength equivalent medium from well-log data  

NASA Astrophysics Data System (ADS)

Backus averaging is often applied to well logs in order to estimate the elastic properties of a stack of thin layers at a longer wavelength to be used in seismic data analysis. Schoenberg and Muir extended Backus's method to layers with arbitrary anisotropy, but simple analytical equations are available for isotropic and transversely isotropic layers only. There is growing exploration interest in shale reservoirs, which exhibit lower symmetry seismic anisotropy if the reservoir is fractured. Here, simple analytical equations for Backus averaging are presented for symmetries up to monoclinic, of which averaging equations for orthorhombic and monoclinic layers are new. After Backus averaging, a stack of isotropic layers results in a vertical transverse isotropy (VTI), a stack of VTI layers results in a VTI, a stack of horizontal transverse isotropy layers results in an orthorhombic, a stack of orthorhombic layers results in an orthorhombic and a stack of monoclinic layers results in a monoclinic. Workflows for Backus averaging are presented along with numerical examples using well-log data from the Haynesville shale play in East Texas, USA.

Kumar, Dhananjay

2013-10-01

173

Well logging interpretation of production profile in horizontal oil-water two phase flow pipes  

NASA Astrophysics Data System (ADS)

Due to the complicated distribution of local velocity and local phase hold up along the radial direction of pipe in horizontal oil-water two phase flow, it is difficult to measure the total flow rate and phase volume fraction. In this study, we carried out dynamic experiment in horizontal oil-water two phases flow simulation well by using combination measurement system including turbine flowmeter with petal type concentrating diverter, conductance sensor and flowpassing capacitance sensor. According to the response resolution ability of the conductance and capacitance sensor in different range of total flow rate and water-cut, we use drift flux model and statistical model to predict the partial phase flow rate, respectively. The results indicate that the variable coefficient drift flux model can self-adaptively tone the model parameter according to the oil-water two phase flow characteristic, and the prediction result of partial phase flow rate of oil-water two phase flow is of high accuracy.

Zhai, Lu-Sheng; Jin, Ning-De; Gao, Zhong-Ke; Zheng, Xi-Ke

2012-03-01

174

35. GEOCHEMICAL WELL LOGS FROM THE ARGO ABYSSAL PLAIN AND EXMOUTH PLATEAU, NORTHEAST INDIAN OCEAN, SITES 765 AND 766 OF LEG 1231  

Microsoft Academic Search

Geochemical well logs were obtained in sediments at Site 765 and in both sediments and basalts at Site 766 of Leg 123. Corrections have been applied to the logs to account for variations in hole size, drilling fluid interference, and casing or drill pipe attenuation. Weight fractions of the major oxides and of calcium carbonate have been calculated from the

Elizabeth Lewis Pratson; Cristina Broglia; David Castillo

175

Assessing spatial uncertainty in reservoir characterization for carbon sequestration planning using public well-log data: A case study  

USGS Publications Warehouse

Mapping and characterization of potential geologic reservoirs are key components in planning carbon dioxide (CO2) injection projects. The geometry of target and confining layers is vital to ensure that the injected CO2 remains in a supercritical state and is confined to the target layer. Also, maps of injection volume (porosity) are necessary to estimate sequestration capacity at undrilled locations. Our study uses publicly filed geophysical logs and geostatistical modeling methods to investigate the reliability of spatial prediction for oil and gas plays in the Medina Group (sandstone and shale facies) in northwestern Pennsylvania. Specifically, the modeling focused on two targets: the Grimsby Formation and Whirlpool Sandstone. For each layer, thousands of data points were available to model structure and thickness but only hundreds were available to support volumetric modeling because of the rarity of density-porosity logs in the public records. Geostatistical analysis based on this data resulted in accurate structure models, less accurate isopach models, and inconsistent models of pore volume. Of the two layers studied, only the Whirlpool Sandstone data provided for a useful spatial model of pore volume. Where reliable models for spatial prediction are absent, the best predictor available for unsampled locations is the mean value of the data, and potential sequestration sites should be planned as close as possible to existing wells with volumetric data. ?? 2009. The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.

Venteris, E. R.; Carter, K. M.

2009-01-01

176

Results concerning the use of seismic and well log data for defining the geological model of the productive structures on the Romanian Continental Shelf of the Black Sea  

SciTech Connect

The contribution of the 3D seismics on the East-Lebada Structure of the Romanian Continental Shelf of the Black Sea, together with the complex well logging have led to the improvement of the reservoir geological model. The interpretation has been performed on 3d seismic profiles. Time migrated profiles were interpreted, by means of the program system OASIIS. The acoustic logging data were used for calibration, in order to identify the reflections corresponding to the geological boundary. By means of these reflections on the seismic profiles, the adequate geological model has been defined. A system of tectonic accidents which were not known till now were rendered evident. The interpretation of the complex well loggings, through the Well Log Analysis Program System - Express - allowed to determine the petrophysical-petrographical parameters necessary for reservoir evaluation, in correlation with core analysis. Thus, four horizons corresponding to the Albian age with favorable collector properties were rendered evident, in alternance with unfavorable collector properties zones. The well logs, performed at different time periods and with different tools were corrected and standardized for the well environment conditions and, depending on the logging program, different program modules were used to obtain the most adequate results. The parameter averaging performed by zones, for each well, together with the image furnished by the seismic data, allowed us to build the final geometrical and isoparametric model of the reservoir, used for further reservoir simulation. Based on the results obtained, the analysis was extended to West-Lebada Structure.

Babskow, A.; Baleanu, I.; Popa, D. [Institute for Research and Technology, Prahova (Romania)] [and others

1995-08-01

177

Evaluating hydrocarbon source rock for unconventional shale oil play from seismic and well log data; Kingak Shale, North Slope, Alaska  

NASA Astrophysics Data System (ADS)

It has been proposed that Acoustic impedance (AI) responses can be used to estimate total organic carbon (TOC) within thick, clay rich shale. The purpose of this work is to evaluate the effectiveness of the AI inversion technique, and establish a methodology that can be applied to other basins. The Kingak Formation (lower Jurassic to early Cretaceous), located on the North Slope of Alaska, has been extensively evaluated for its unconventional potential. The Kingak is shale and is known to have greater than 30 percent clay. Because clay has ductile properties it makes it difficult to stimulate a well through hydraulic fracturing. This AI inversion technique was tested by utilizing synthetic seismograms to create an AI curve generated using The KINGDOM Software©. The synthetic seismograms were used to ensure a well log to seismic match. The synthetic seismograms also created an AI curve along the well. From these synthetic seismograms the AI value was compared to TOC values. It was from this comparison that a trend was observed that did not match the predicted trend. I believe the discrepancy observed was due to the sampling method. Based on this observation, I conclude that the method of tracking TOC with AI responses requires extremely controlled sampling methods; therefore it is not a beneficial method of revisiting old data sets in hopes of identifying new prospects.

Leedberg, Sarah Elisabeth

178

Inference of S-wave velocities from well logs using a Neuro-Fuzzy Logic (NFL) approach  

NASA Astrophysics Data System (ADS)

The knowledge of S-wave velocity values is important for a complete characterization and understanding of reservoir rock properties. It could help in determining fracture propagation and also to improve porosity prediction (Cuddy and Glover, 2002). Nevertheless the acquisition of S-wave velocity data is rather expensive; hence, for most reservoirs usually this information is not available. In the present work we applied a hybrid system, that combines Neural Networks and Fuzzy Logic, in order to infer S-wave velocities from porosity (?), water saturation (Sw) and shale content (Vsh) logs. The Neuro-Fuzzy Logic (NFL) technique was tested in two wells from the Guafita oil field, Apure Basin, Venezuela. We have trained the system using 50% of the data randomly taken from one of the wells, in order to obtain the inference equations (Takani-Sugeno-Kang (TSK) fuzzy model). Equations using just one of the parameters as input (i.e. ??, Sw or Vsh), combined by pairs and all together were obtained. These equations were tested in the whole well. The results indicate that the best inference (correlation between inferred and experimental data close to 80%) is obtained when all the parameters are considered as input data. An increase of the equation number of the TSK model, when one or just two parameters are used, does not improve the performance of the NFL. The best set of equations was tested in a nearby well. The results suggest that the large difference in the petrophysical and lithological characteristics between these two wells, avoid a good inference of S-wave velocities in the tested well and allowed us to analyze the limitations of the method.

Aldana, Milagrosa; Coronado, Ronal; Hurtado, Nuri

2010-05-01

179

Clay identification and amount measured by laboratory techniques compared to well log responses: Application to tight gas sands and shales  

Microsoft Academic Search

Identification and amount of clay in tight sands and shales calculated by downhole log interpretation techniques have been compared with those measured by a variety of analytical laboratory methods. The US DOE's Multiwell Experiment in the Piceance Creek Basin, Colorado has provided a wide selection of core and extensive logging data from the Mesaverde Formation. The samples were analyzed for

D. M. Heinze

1985-01-01

180

Completion reports, core logs, and hydrogeologic data from wells and piezometers in Prospect Gulch, San Juan County, Colorado  

USGS Publications Warehouse

In the late nineteenth century, San Juan County, Colorado, was the center of a metal mining boom in the San Juan Mountains. Although most mining activity ceased by the 1990s, the effects of historical mining continue to contribute metals to ground water and surface water. Previous research by the U.S. Geological Survey identified ground-water discharge as a significant pathway for the loading of metals to surface water from both acid-mine drainage and acid-rock drainage. In an effort to understand the ground-water flow system in the upper Animas River watershed, Prospect Gulch was selected for further study because of the amount of previous data provided in and around that particular watershed. In support of this ground-water research effort, wells and piezometers were installed to allow for coring during installation, subsurface hydrologic testing, and the monitoring of ground-water hydraulic heads and geochemistry. This report summarizes the data that were collected during and after the installation of these wells and piezometers and includes (1) subsurface completion details, (2) locations and elevations, (3) geologic logs and elemental data, (4) slug test data for the estimation of subsurface hydraulic conductives, and (5) hydraulic head data.

Johnson, Raymond H.; Yager, Douglas B.

2006-01-01

181

Application of Time-Series Analysis to Induced Gamma Ray Spectroscopy Logs From Two Cold Lake Heavy-Oil Observation Wells  

Microsoft Academic Search

This paper reports on induced gamma ray spectroscopy (IGRS) logs from two cyclic-steam-stimulation observation wells in Cold Lake that were analyzed to determine the vertical resolution and repeatability of data derived from gamma rays of inelastic and capture neutron reactions. Time-series analysis, a technique that uses the Fourier representation of the log data, was used to quantify the vertical resolution

Daniel Georgi

1991-01-01

182

Determination of petrophysical properties of geothermal reservoirs in southern Denmark by integrating information from well logs and reflection seismic data  

NASA Astrophysics Data System (ADS)

As part of the efforts to reduce CO2 emission, geothermal energy is an important source for future energy production in Denmark, and several research programs deal with this specific subject e.g. "The geothermal energy potential in Denmark - reservoir properties, temperature distribution and models for utilization", funded by the Danish Strategic Research Council and "GEOPOWER" which is part of an EU INTERREG-program focused on southern Denmark and northernmost Germany. For geothermal energy to be economically sustainable porous and permeable rocks needs to be present at a depth where the temperature is sufficiently high. Utilization of geothermal energy in Denmark and plans for the future are concentrated on low enthalpy basin reservoirs for district heating. Major modeling studies are carried out to establish the temperature distribution in the Danish subsurface. This project deals with the reservoir properties. The geothermal reservoir exploited so far in the southern Danish area is restricted to the lower Jurassic-Triassic Gassum Formation. The Gassum Formation is a shallow marine to fluvial deposit composed of sandy to silty sediments, occasionally with coal layers, i.e. a lateral and stratigraphically heterogeneous rock. This formation is encountered only in deep hydrocarbon exploration wells and in wells of the Sřnderborg Geothermal plant. Due to the very low number and low density of wells and the limited rock material recovered during drilling, the knowledge of lateral variations of reservoir properties in terms of porosity, permeability and thickness, is limited and so far unsatisfactorily mapped. The main risks in the utilization of geothermal energy from the subsurface of Denmark are therefore regional, as well as local, variations in the production potential of warm water, whereas the temperature can be assessed fairly precisely due to the thermal models available. Here we use petrophysical wells logs available from hydrocarbon exploration wells for determination of reservoir characteristics in combination with a neural network seismic attribute analysis (courtesy of OpendTect) of seismic reflection data available in the area which are both 2D and 3D industrial seismic data, recently acquired. By this combined data analysis we develop procedures for reducing the risk of drilling tight reservoirs as well as for getting a better understanding of the geological evolution of potential geothermal reservoir units.

Rasmussen, Marie L.; Balling, Niels; Bording, Thue S.; Clausen, Ole R.

2013-04-01

183

Artificial Neural Networks applied to estimate permeability, porosity and intrinsic attenuation using seismic attributes and well-log data  

NASA Astrophysics Data System (ADS)

Permeability and porosity are two fundamental reservoir properties which relate to the amount of fluid contained in a reservoir and its ability to flow. The intrinsic attenuation is another important parameter since it is related to porosity, permeability, oil and gas saturation and these parameters significantly affect the seismic signature of a reservoir. We apply Artificial Neural Network (ANN) models to predict permeability (k) and porosity (?) for a carbonate aquifer in southeastern Florida and to predict intrinsic attenuation (1/Q) for a sand-shale oil reservoir in northeast Texas. In this study, the Gamma test (a revolutionary estimator of the noise in a data set) has been used as a mathematically non-parametric nonlinear smooth modeling tool to choose the best input combination of seismic attributes to estimate k and ?, and the best combination of well-logs to estimate 1/Q. This saves time during the construction and training of ANN models and also sets a lower bound for the mean squared error to prevent over-training. The Neural Network method successfully delineates a highly permeable zone that corresponds to a high water production in the aquifer. The Gamma test found nonlinear relations that were not visible to linear regression allowing us to generalize the ANN estimations of k, ? and 1/Q for their respective sets of patterns that were not used during the learning phase.

Iturrarán-Viveros, Ursula; Parra, Jorge O.

2014-08-01

184

Sweet spots discrimination in shale gas reservoirs using seismic and well-logs data. A case study from the Worth basin in the Barnett shale  

NASA Astrophysics Data System (ADS)

Here, we present a case study of sweet spots discrimination in shale gas reservoirs located in the Worth basin of the Barnett shale using seismic and well-logs data. Seismic attributes such the Chaos and the ANT-Tracking are used for natural fractures system identification from seismic data, the maps of the stress and the Poisson ratio obtained from the upscaling of well-logs data of a horizontal well are able to provide an information about the drilling direction which is usually in the minimum horizontal stress profile, the map of the Poisson ratio can provide an information hardness of the source rock. The set of well logs data is used for geo-mechanical and petrophysical discrimination of the sweet spots, after discrimination the identified zones are useful for reserves estimation from unconventional shale gas reservoir.

Aliouane, Leila; Ouadfeul, Sid-Ali; Boudella, Amar

2014-05-01

185

Clay identification and amount measured by laboratory techniques compared to well log responses: application to tight gas sands and shales  

SciTech Connect

Identification and amount of clay in tight sands and shales calculated by downhole log interpretation techniques have been compared with those measured by a variety of analytical laboratory methods. The US DOE's Multiwell Experiment in the Piceance Creek Basin, Colorado has provided a wide selection of core and extensive logging data from the Mesaverde Formation. The samples were analyzed for clay content in the laboratory using all of the following methods: optical petrography, x-ray diffraction, bulk chemical, acetate method for cation exchange capacity, sedigraph, pipet, and centrifuge. Potassium, uranium, and thorium (KUT) concentrations were determined utilizing the following techniques: x-ray fluorescence, atomic absorption, neutron activation, gamma spectroscopy and alpha spectrometry. This multiple technique approach was used in order to corroborate laboratory data. The results clearly show that relying on one or two methods can result in significant error. Laboratory data point out that this small sampling of log-defined good sands and shales actually represents a variety of lithologies and compositions. Also, it is apparent that the log data and log-based interpretations of clay and KUT content in these samples are in significant disagreement with the laboratory-derived information. The KUT logs of the two service companies represented also yielded different clay types based on the Th/K ratios. The results put forth in this study point out some of the difficulties in accurately making the calibrations commonly used in interpreting the clay quantity of a given interval. Two apparently identical gamma ray responses may represent two fairly different mineral compositions or distributions. Core analysis is necessary in order to accurately apply logging interpretations in a formation of this type. 30 references, 4 figures, 8 tables.

Heinze, D.M.

1985-03-01

186

Inference of strata separation and gas emission paths in longwall overburden using continuous wavelet transform of well logs and geostatistical simulation  

NASA Astrophysics Data System (ADS)

Prediction of potential methane emission pathways from various sources into active mine workings or sealed gobs from longwall overburden is important for controlling methane and for improving mining safety. The aim of this paper is to infer strata separation intervals and thus gas emission pathways from standard well log data. The proposed technique was applied to well logs acquired through the Mary Lee/Blue Creek coal seam of the Upper Pottsville Formation in the Black Warrior Basin, Alabama, using well logs from a series of boreholes aligned along a nearly linear profile. For this purpose, continuous wavelet transform (CWT) of digitized gamma well logs was performed by using Mexican hat and Morlet, as the mother wavelets, to identify potential discontinuities in the signal. Pointwise Hölder exponents (PHE) of gamma logs were also computed using the generalized quadratic variations (GQV) method to identify the location and strength of singularities of well log signals as a complementary analysis. PHEs and wavelet coefficients were analyzed to find the locations of singularities along the logs. Using the well logs in this study, locations of predicted singularities were used as indicators in single normal equation simulation (SNESIM) to generate equi-probable realizations of potential strata separation intervals. Horizontal and vertical variograms of realizations were then analyzed and compared with those of indicator data and training image (TI) data using the Kruskal-Wallis test. A sum of squared differences was employed to select the most probable realization representing the locations of potential strata separations and methane flow paths. Results indicated that singularities located in well log signals reliably correlated with strata transitions or discontinuities within the strata. Geostatistical simulation of these discontinuities provided information about the location and extents of the continuous channels that may form during mining. If there is a gas source within their zone of influence, paths may develop and allow methane movement towards sealed or active gobs under pressure differentials. Knowledge gained from this research will better prepare mine operations for potential methane inflows, thus improving mine safety.

Karacan, C. Özgen; Olea, Ricardo A.

2014-06-01

187

Hydrogeologic Interpretations of Natural-Gamma Logs for 31 Shallow Wells in the Memphis, Tennessee Area. National Water-Quality Assessment Program.  

National Technical Information Service (NTIS)

The purpose of this report is to describe the stratigraphy of the hydrogeologic units at each of the 31 monitoring wells. The report presents the natural-gamma-log data that were measured for the Mississippi Embayment study unit monitoring wells in the Me...

E. W. Strom

1997-01-01

188

Geophysical-well-log data for study of water flow in fractures near Mirror Lake, West Thornton, New Hampshire  

USGS Publications Warehouse

Four closely spaced boreholes were drilled through approximately 20 meters of till into schist bedrock near Mirror Lake, West Thornton, New Hampshire. The site was selected for borehole geophysical research because it is included in a detailed groundwater study where the effects of flow in fractures on flow in overlying drift deposits is being studied. Three of the boreholes are approximately 100 meters in depth, and the fourth is approximately 230 meters in depth. All four boreholes were logged with caliper, acoustic, gamma, single-point-resistivity, and acoustic televiewer logs. Fracture sets dipping approximately 45 degrees to the east were detected in all four boreholes. Two sets of deeper fractures were detected near the bottom of the deepest borehole. Acoustic waveform logs were obtained in all boreholes using three different source frequencies, 34, 15, and 5 kilohertz, for future comparison with surface to borehole seismic data. (USGS)

Paillet, F. L.

1985-01-01

189

Seismic Interpretation and Well Logging Results of a Deep Borehole into the Canadian Shield in Northeastern Alberta: Preliminary Results  

NASA Astrophysics Data System (ADS)

With the increasing awareness of the need for the reduction of carbon emissions globally, geothermal energy, which offers a potential for cleaner energy generation, is one potential new source. In Alberta, these geothermal resources are likely to be found in the sedimentary basin, or in the deeper crystalline basement rocks. Alberta exhibits a very low geothermal gradient compared to other existing geothermal fields located in areas of volcanic and tectonic activity. To mitigate this effect, the focus in Alberta will involve the development of engineered geothermal systems (EGS) in the target resource. This project is part of the Helmholtz-Alberta Initiative (HAI), which is a research collaboration between scientists in Germany and Canada on energy projects for cleaner energy production. The first goal for EGS research and development is to develop a detailed geological-geophysical characterization of selected sites to delineate potential geothermal reservoirs in Northern Alberta. One of the selected sites is in the Fort McMurray area. Using an existing deep borehole that reaches a depth of 2.3 km into the crystalline basement, our aim is to identify geological features such as zones of fractures in the basin and/or basement that could provide an indication of enhanced fluid flow potential - a necessary component for any geothermal systems to be viable. The earlier stage of our research involves re-processing of surface seismic data. This helps to improve the signal-to-noise ratio for the geological interpretation of the subsurface, such as the locations of saline aquifers and faults that allow heat flow in the rocks, and zones of fractures that may indicate elevated porosity. Current re-processing of the seismic data displays sets of dipping reflectors which may intersect the borehole. Zero offset and walkaway vertical seismic profiles (VSP) were conducted at the borehole for direct comparison with the surface seismic sections. They are also useful in obtaining information about the reflectivity and the velocity structure of the subsurface. The full integration of surface seismic data, VSP data, and well logs are expected to provide a detailed characterization of the sedimentary basin and crystalline basement rocks of the Canadian Shield in Northeastern Alberta. In particular, the unusually low fluid pressures in the well may be related to states of stress that are likely still influenced by post-glacial rebound.

Chan, J.; Schmitt, D.; Majorowicz, J. A.; Nieuwenhuis, G.; Poureslami Ardakani, E.; van der Baan, M.; Sahay, P. N.; Kueck, J.; Abasolo, M. R.

2011-12-01

190

Identification and Characterization of Basalt and Sediment Units Based On Wireline Logs From The Lopra Deep Well, Faroe Islands, Ne-atlantic Ocean  

NASA Astrophysics Data System (ADS)

In 1980-81 two deep wells were drilled into the basalt covering the Faroe Islands which is an island group consisting of 18 islands in the Northeast Atlantic Ocean. The basalt is subaerial extruded in relation to the opening of the Northeast Atlantic and is on the Faroe Islands divided into three series. In order to drill the subbasalt geology one of the wells, Lopra-1, was drilled in the lower series at the stratigraphic lowest level. The well was abandoned in a depth of 2185 m and only sparsely logged. In 1996 16 oil companies formed the Lopra-consortium and the well was deepened. The plateaubasalt was penetrated and as part of the investigation an extensive logging suite was carried out. Based on the data obtained from the log suite and interpreted on a SGI workstation using Landmark software (Stratwork and Petrowork) it is possible to iden- tify individual sediment layers and lava flows, and to divide lava flows into crust and core. On the poster the full profile of the 86 individual flow-units, 18 compound flows and 2 dolerite dikes and 52 sedimentary/tuffaceous layers are shown together with 5 logtypes reflecting physical properties and 4 logs representing chemical properties. Based on this separation into units a statistical treatment is carried out and physical properties values of the lower basalt series on the Faroe Islands are obtained and com- pared to values obtained from other basalt covered regions of the world. Cross-plots are shown which confirm the subdivision. The logs representing the physical proper- ties show a cyclic behaviour reflecting the flow-units although pronounced variations are found comparing the individual lava flows. The geochemical logs do not reflect this cyclic behaviour but shows that high and low radioactive flow-units exist.

Boldreel, L. O.

191

Hydrogeologic Framework of the Upper Santa Cruz Basin (Arizona and Sonora) using Well Logs, Geologic Mapping, Gravity, Magnetics, and Electromagnetics  

NASA Astrophysics Data System (ADS)

In 2006, the U.S. Congress passed the U.S.-Mexico Transboundary Aquifer Assessment Act which provides a framework for study of aquifers shared by the United States and Mexico. The aquifer of the Upper Santa Cruz Basin was chosen as one of four priority aquifers for several reasons, including water scarcity, a population greater than 300,000, groundwater as the sole source of water for human use, and a riparian corridor that is of regional significance for migratory birds and other animals. Several new mines are also being proposed for this area which may affect water quality and availability. To date, a number of studies have been carried out by a binational team composed of the U.S. Geological Survey, the Mexican National Water Commission, and the Universities of Arizona and Sonora. Construction of a cross-border hydrogeologic framework model of the basin between Amado, Arizona and its southern boundary in Sonora is currently a high priority. The relatively narrow Santa Cruz valley is a structural basin that did not experience the same degree of late Cenozoic lateral extension and consequent deepening as found in other basin-and-range alluvial basins, such as the Tucson basin, where basin depth exceeds 3000 meters. This implies that storage may be much less than that found in other basin-and-range aquifers. To investigate the geometry of the basin and facies changes within the alluvium, a database of over one thousand well logs has been developed, geologic mapping and transient electromagnetic (TEM) surveys have been carried out, and information from previous electromagnetic, magnetic, and gravity studies is being incorporated into the hydrogeologic framework. Initial geophysical surveys and analyses have focused on the portion of the basin west of Nogales, Arizona, because it supplies approximately 50% of that city's water. Previous gravity and magnetic modeling indicate that this area is a narrow, fault-controlled half graben. Preliminary modeling of airborne and ground-based transient electromagnetic surveys corroborates earlier conclusions from the gravity modeling that depth to bedrock is greater than 500 meters in some locations. Results from other portions of the study area including Mexico are still being evaluated and incorporated into the three-dimensional hydrologic framework which will ultimately be used to construct a groundwater flow model.

Callegary, J. B.; Page, W. R.; Megdal, S.; Gray, F.; Scott, C. A.; Berry, M.; Rangel, M.; Oroz Ramos, L.; Menges, C. M.; Jones, A.

2011-12-01

192

Integrating seismic attribute maps and well logs for porosity modeling in a west Texas carbonate reservoir: addressing the scale and precision problem  

Microsoft Academic Search

A 3-D porosity field in a west Texas carbonate reservoir is modeled conditional to both “hard” porosity data sampled by wells and 2-D seismic attribute map with less vertical resolution than the well log data. The difference-of-scales between the two sources of data is resolved by a prior 2-D estimation of vertically averaged porosity using well and seismic data. These

Tingting Yao; Andre G. Journel

2000-01-01

193

Hydrologic characteristics of the Madison Limestone, the Minnelusa Formation, and equivalent rocks as determined by well-logging formation evaluation, Wyoming, Montana, South Dakota, and North Dakota  

Microsoft Academic Search

Geophysical logs from wells distributed throughout the Powder River Basin were digitized, processed, and interpreted to get a regional understanding of the lithologic and ground-water characteristics of aquifers in the Madison Limestone and Minnelusa Formation. The percentage of sand, porosity, and apparent ground-water resistivity of the Minnelusa closely follow structural trends in the basis. Values increase from the structural axis

W. J. Head; R. H. Merkel

1977-01-01

194

Fractured-bedrock aquifer studies based on a descriptive statistics of well-logging data: A case study from the Dajia River basin, Taiwan  

NASA Astrophysics Data System (ADS)

A simple descriptive-statistical approach is proposed for evaluating the transmissivity of fractured-bedrock under field conditions. Based on standard well logging and identification of structural discontinuities from borehole televiewer, the approach consists of four steps: (1) determination of discontinuity properties, namely the frequency of discontinuities and the ratio of open fractures along the borehole; (2) ranking the three well logs and the discontinuity properties into tertiles (high-to-low); (3) performing statistical analysis ( F-test) for the three well logs to assess the significance of open fractures on the water-transmitting potential and then assigned a weighting factor; and (4) a semi-quantitative indicator, RGVFO, is obtained by multiplying all predictive indexes and weighting factors. It is a multi-criteria evaluation procedure that elucidates the quantitative and qualitative importance of all selected geophysical indexes. A high cross-correlation between transmissivity to RGVFO value is found, which indicates that by a combined consideration of well logging and structural discontinuities, an appropriate estimate of bedrock water-transmitting potential can be derived.

Chou, Po-Yi; Hsu, Shih-Meng; Chen, Po-Jui; Lin, Jung-Jun; Lo, Hung-Chieh

2014-06-01

195

Digital signal processing and interpretation of full waveform sonic log for well BP-3-USGS, Great Sand Dunes National Park and Preserve, Alamosa County, Colorado  

USGS Publications Warehouse

Along the Great Sand Dunes National Park and Preserve boundary (fig. 1), 10 monitoring wells were drilled by the National Park Service in order to monitor water flow in an unconfined aquifer spanning the park boundary. Adjacent to the National Park Service monitoring well named Boundary Piezometer Well No. 3, or BP-3, the U.S. Geological Survey (USGS) drilled the BP-3-USGS well. This well was drilled from September 14 through 17, 2009, to a total depth of 99.4 meters (m) in order to acquire additional subsurface information. The BP-3-USGS well is located at lat 37 degrees 43'18.06' and long -105 degrees 43'39.30' at a surface elevation of 2,301 m. Approximately 23 m of core was recovered beginning at a depth of 18 m. Drill cuttings were also recovered. The wireline geophysical logs acquired in the well include natural gamma ray, borehole caliper, temperature, full waveform sonic, density, neutron, resistivity, and induction logs. The BP-3-USGS well is now plugged and abandoned. This report details the full waveform digital signal processing methodology and the formation compressional-wave velocities determined for the BP-3-USGS well. These velocity results are compared to several velocities that are commonly encountered in the subsurface. The density log is also discussed in context of these formation velocities.

Burke, Lauri

2011-01-01

196

Application of well log analysis for source rock evaluation in the Duwi Formation, Southern Gulf of Suez, Egypt  

NASA Astrophysics Data System (ADS)

Several models were developed to use the conventional wireline logs for evaluating the thermal maturity of the source rock and calculating the total organic carbon (TOC) content. Application of these models for the Duwi Formation, southern Gulf of Suez, Egypt, is the main purpose of this paper. Gamma ray, density, sonic, resistivity and neutron are the commonly used wireline logs to identify and quantify source rock. The results, which compared with the results obtained from the Rock-Eval pyrolysis show that cautions must be taken into consideration when applied these models because most of the models are empirical and their validation takes place under certain conditions. It can be concluded that the Duwi Formation represents very good source rock capable of generating a significant amount of hydrocarbon of oil-prone type II. The kerogen is waxy sapropel related to marine plankton deposited under reduced condition.

El Sharawy, Mohamed S.; Gaafar, Gamal R.

2012-05-01

197

Applying NMR spin-echo logging to Shaly Sand Formation evaluation: Case studies of Rocky Mountain region gas wells  

Microsoft Academic Search

Conventional wireline logs often fail to provide a reliable evaluation of reservoir quality and producibility in shaly mud formations, particularly in the shaly gas sand reservoirs of the Rocky Mountains which are characterized by low porosity (i.e., <15 pu), low permeability (0.1 to 1 md), very fine grain size, and high irreducible water saturations. A new-generation nuclear magnetic resonance (NMR)

R. K. Ladtkow; B. J. Stambaugh; D. Mardon

1995-01-01

198

Clay identification and amount measured by laboratory techniques compared to well log responses: Application to tight gas sands and shales  

NASA Astrophysics Data System (ADS)

Identification and amount of clay in tight sands and shales calculated by downhole log interpretation techniques have been compared with those measured by a variety of analytical laboratory methods. The US DOE's Multiwell Experiment in the Piceance Creek Basin, Colorado has provided a wide selection of core and extensive logging data from the Mesaverde Formation. The samples were analyzed for clay content in the laboratory using all of the following methods: optical petrography, X-ray diffraction, bulk chemical, acetate method for cation exchange capacity, sedigraph, pipet, and centrifuge. Potassium, uranium, and thorium (KUT) concentrations were determined utilizing the following techniques: X-ray fluorescence, atomic absorption, neutron activation, gamma spectroscopy and alpha spectrometry. This multiple technique approach was used in order to corroborate laboratory data. The results clearly show that relying on one or two methods can result in significant error. Laboratory data point out that this small sampling of log-defined good sands and shales actually represents a variety of lithologies and compositions.

Heinze, D. M.

1985-03-01

199

Lithofacies prediction from well log data using a multilayer perceptron (MLP) and Kohonen's self-organizing map (SOM) - a case study from the Algerian Sahara  

NASA Astrophysics Data System (ADS)

In this paper, a combination of supervised and unsupervised leanings is used for lithofacies classification from well log data. The main idea consists of enhancing the multilayer perceptron (MLP) learning by the output of the self-organizing map (SOM) neural network. Application to real data of two wells located the Algerian Sahara clearly shows that the lithofacies model built by the neural combination is able to give better results than a self-organizing map.

Ouadfeul, S.-A.; Aliouane, L.

2013-06-01

200

Records of wells, drillers' logs, water-level measurements, and chemical analyses of ground water in Chambers, Liberty, and Montgomery counties, Texas, 1980-84  

USGS Publications Warehouse

Information on major new water wells in Chambers, Liberty, and Montgomery Counties was compiled by the U.S. Geological Survey from 1980 through 1984. This report presents the results of the hydrologic data collection on new large-capacity and other selected wells, including well location and completion data, drillers ' logs of the strata penetrated, water levels, and chemical quality of the produced water. These water-well data are supplementary to similar data on older wells in these counties and descriptive evaluations of the groundwater resources which have been published previously. (USGS)

Williams, J. F., III; Coplin, L. S.; Ranzau, C. E., Jr.; Lind, W. B.

1986-01-01

201

Records of wells, drillers' logs, water-level measurements, and chemical analyses of ground water in Brazoria, Fort Bend, and Waller counties, Texas, 1980-84  

USGS Publications Warehouse

Information on major new water wells in Brazoria, Fort Bend, and Waller Counties was compiled by the U.S. Geological Survey from 1980 through 1984. This report presents the results of the hydrologic data collection on new large-capacity and other selected wells, including well location and completion data, drillers ' logs of the strata penetrated, water levels, and chemical quality of the produced water. These water-well data are supplementary to similar data on older wells in these counties and descriptive evaluations of the groundwater resources which have been published previously. (USGS)

Williams, J. F., III; Ranzau, C. F., Jr.; Lind, W. B.; Coplin, L. S.

1986-01-01

202

A fuzzy logic approach for estimation of permeability and rock type from conventional well log data: an example from the Kangan reservoir in the Iran Offshore Gas Field  

NASA Astrophysics Data System (ADS)

Permeability and rock type are the most important rock properties which can be used as input parameters to build 3D petrophysical models of hydrocarbon reservoirs. These parameters are derived from core samples which may not be available for all boreholes, whereas, almost all boreholes have well log data. In this study, the importance of the fuzzy logic approach for prediction of rock type from well log responses was shown by using an example of the Vp to Vs ratio for lithology determination from crisp and fuzzy logic approaches. A fuzzy c-means clustering technique was used for rock type classification using porosity and permeability data. Then, based on the fuzzy possibility concept, an algorithm was prepared to estimate clustering derived rock types from well log data. Permeability was modelled and predicted using a Takagi-Sugeno fuzzy inference system. Then a back propagation neural network was applied to verify fuzzy results for permeability modelling. For this purpose, three wells of the Iran offshore gas field were chosen for the construction of intelligent models of the reservoir, and a forth well was used as a test well to evaluate the reliability of the models. The results of this study show that fuzzy logic approach was successful for the prediction of permeability and rock types in the Iran offshore gas field.

Kadkhodaie Ilkhchi, Ali; Rezaee, Mohammadreza; Moallemi, Seyed Ali

2006-12-01

203

Real-time formation evaluation using a well-site data management system to integrate MWD, surface measurements, and enhanced mud logging data  

SciTech Connect

With the advent of measurement while drilling (MWD), a new source of quantitative data became available during the drilling process. The availability of wireline log-type data while drilling has led to a need that traditional mud-logging methods be augmented and enhanced to provide more quantitative correlative data sources and benchmark standards for the lithologic normalization of MWD data. Together these data can be integrated within a single well-site data base to provide effective formation evaluation while the drilling process continues. The data base may be so structured that later available data, such as wireline logs, may be input to provide confirmation and refinement of real-time evaluations. Similarly, the data base may be primed with geophysical and geological pronoses prior to drilling. Case histories show the effective real-time determination of true total and effective porosities, fluid saturations, and estimates of formation characteristics, such as mineralogy and permeability. In each example, when departures between early and late data sets occur (e.g., wireline logs or formation tests), the data variation results from changes in downhole conditions, and the data can be used to enhance formation evaluation by adding a dynamic component.

Whittaker, A.; Brooks, A.; Dowsett, R.; MacPherson, J.; Nigh, E.

1986-04-01

204

Estimating the Amount of Eroded Section in a Partially Exhumed Basin from Geophysical Well Logs: An Example from the North Slope  

USGS Publications Warehouse

The reconstruction of burial and thermal histories of partially exhumed basins requires an estimation of the amount of erosion that has occurred since the time of maximum burial. We have developed a method for estimating eroded thickness by using porosity-depth trends derived from borehole sonic logs of wells in the Colville Basin of northern Alaska. Porosity-depth functions defined from sonic-porosity logs in wells drilled in minimally eroded parts of the basin provide a baseline for comparison with the porosity-depth trends observed in other wells across the basin. Calculated porosities, based on porosity-depth functions, were fitted to the observed data in each well by varying the amount of section assumed to have been eroded from the top of the sedimentary column. The result is an estimate of denudation at the wellsite since the time of maximum sediment accumulation. Alternative methods of estimating exhumation include fission-track analysis and projection of trendlines through vitrinite-reflectance profiles. In the Colville Basin, the methodology described here provides results generally similar to those from fission-track analysis and vitrinite-reflectance profiles, but with greatly improved spatial resolution relative to the published fission-track data and with improved reliability relative to the vitrinite-reflectance data. In addition, the exhumation estimates derived from sonic-porosity logs are independent of the thermal evolution of the basin, allowing these estimates to be used as independent variables in thermal-history modeling.

Burns, W. Matthew; Hayba, Daniel O.; Rowan, Elisabeth L.; Houseknecht, David W.

2007-01-01

205

A simple well-logging tool using boron-lined sodium iodide scintillators and an 241Am-Be neutron source.  

PubMed

A couple of 2-inch by 2-inch right cylinder sodium iodide scintillators and an Am-Be radioisotope neutron source have been used in a neutron porosity well-logging tool to explore the variation of hydrogen contents in a prototype formation. Both Monte Carlo N-particle transport code simulation and experimental results of the near- to far-detector responses confirm the reliable sensitivity of proposed tool to the formation porosity. PMID:22434921

Rasoulinejad, M; Izadi Najafabadi, R; Ghal-Eh, N

2012-09-01

206

The efficiency calibration and development of environmental correction factors for an in situ high-resolution gamma spectroscopy well logging system  

SciTech Connect

A Gamma Spectroscopy Logging System (GSLS) has been developed to study sub-surface radionuclide contamination. Absolute efficiency calibration of the GSLS was performed using simple cylindrical borehole geometry. The calibration source incorporated naturally occurring radioactive material (NORM) that emitted photons ranging from 186-keV to 2,614-keV. More complex borehole geometries were modeled using commercially available shielding software. A linear relationship was found between increasing source thickness and relative photon fluence rates at the detector. Examination of varying porosity and moisture content showed that as porosity increases, relative photon fluence rates increase linearly for all energies. Attenuation effects due to iron, water, PVC, and concrete cylindrical shields were found to agree with previous studies. Regression analyses produced energy-dependent equations for efficiency corrections applicable to spectral gamma-ray well logs collected under non-standard borehole conditions.

Giles, J.R.

1996-05-01

207

Results of borehole geophysical logging and hydraulic tests conducted in Area D supply wells, former US Naval Air Warfare Center, Warminster, Pennsylvania  

USGS Publications Warehouse

Borehole geophysical logging, aquifer tests, and aquifer-isolation (packer) tests were conducted in four supply wells at the former U.S. Naval Air Warfare Center (NAWC) in Warminster, PA to identify the depth and yield of water-bearing zones, occurrence of borehole flow, and effect of pumping on nearby wells. The study was conducted as part of an ongoing evaluation of ground-water contamination at the NAWC. Caliper, natural-gamma, single-point resistance, fluid resistivity, and fluid temperature logs and borehole television surveys were run in the supply wells, which range in depth from 242 to 560 ft (feet). Acoustic borehole televiewer and borehole deviation logs were run in two of the wells. The direction and rate of borehole-fluid movement under non-pumping conditions were measured with a high-resolution heatpulse flowmeter. The logs were used to locate water-bearing fractures, determine probable zones of vertical borehole-fluid movement, and determine the depth to set packers. An aquifer test was conducted in each well to determine open-hole specific capacity and the effect of pumping the open borehole on water levels in nearby wells. Specific capacities ranged from 0.21 to 1.7 (gal/min)/ft (gallons per minute per foot) of drawdown. Aquifer-isolation tests were conducted in each well to determine depth-discrete specific capacities and to determine the effect of pumping an individual fracture or fracture zone on water levels in nearby wells. Specific capacities of individual fractures and fracture zones ranged from 0 to 2.3 (gal/min)/ft. Most fractures identified as water-producing or water-receiving zones by borehole geophysical methods produced water when isolated and pumped. All hydrologically active fractures below 250 ft below land surface were identified as water-receiving zones and produced little water when isolated and pumped. In the two wells greater then 540 ft deep, downward borehole flow to the deep water-receiving fractures is caused by a large difference in head (as much as greater then 49 ft) between water-bearing fractured in the upper and lower part of the borehole. Vertical distribution of specific capacity between land surface and 250 ft below land surface is not related to depth.

Sloto, Ronald A.; Grazul, Kevin E.

1998-01-01

208

Detection of overpressure zones and a statistical model for pore pressure estimation from well logs in the Krishna-Godavari Basin, India  

NASA Astrophysics Data System (ADS)

high pressures, measured by repeat formation tester (RFT) and detected by well log data from 10 wells in the Krishna-Godavari (K-G) Basin, occur in the Vadaparru Shale of Miocene and Raghavapuram Shale of Early Cretaceous age. Overpressures generated by disequilibrium compaction, and pore pressures have been estimated using the conventional Eaton sonic equation with an exponent of 3.0. The observed abnormal pore pressure gradient ranges from 11.85 to 13.10 MPa/km, whereas fracture pressure gradient varies from 17.40 to 19.78 MPa/km. The magnitude of vertical stress (Sv) has a gradient from 21.00 to 23.10 MPa/km. The minimum horizontal principal stress (Sh) magnitude is found to vary from 64 to 77% of the Sv in normally pressured to overpressured sediments. A multiple linear regression model with a squared multiple correlation coefficient (R2) of 0.94 is proposed for pore pressure prediction from gamma ray, density and sonic logs to focus on efficient drilling operations and to prevent borehole instability. The statistical model has been calibrated with the RFT data from five wells covering about 3400 sq. km area of the onshore K-G Basin. The model predicted pore pressure values are in close agreement with the actual RFT data for another four wells including a well in the offshore K-G Basin. Hence, the proposed regression model may be useful for predicting pore pressure from other well logs in the K-G Basin.

Singha, Dip Kumar; Chatterjee, Rima

2014-04-01

209

Well-log seismic sequence stratigraphy of Aruba and its application to the hydrocarbon exploration in the Caribbean Area  

Microsoft Academic Search

Several wells have recently been drilled in offshore Aruba approximately 12 degrees NOrth Latitude and 70 degrees West Longitude, just north of the Westernpart of Venezuela, South Central Caribbean. One of the wells, the Oxy Chuchubi No. 1 well penetrated a largely carbonate section that ranged in age from early Pliocene to early Oligocene to late Eocene at its total

W. W. Wornardt; P. R. Vail

1993-01-01

210

IMPROVED WELL PLUGGING EQUIPMENT AND WASTE MANGEMENT TECHNIQUES EXCEED ALARA GOALS AT THE OAK RIDGE NATIONAL LABORATORY  

SciTech Connect

In 2000, Bechtel Jacobs Company LLC (BJC) contracted Tetra Tech NUS, Inc. (TtNUS) and their sub-contractor, Texas World Operations, Inc. (TWO), to plug and abandon (P&A) 111 wells located in the Melton Valley area of Oak Ridge National Laboratory (ORNL). One hundred and seven of those wells were used to monitor fluid movement and subsurface containment of the low level radioactive liquid waste/grout slurry that was injected into the Pumpkin Valley Shale Formation, underlying ORNL. Four wells were used as hydrofracture injection wells to emplace the waste in the shale formation. Although the practice of hydrofracturing was and is considered by many to pose no threat to human health or the environment, the practice was halted in 1982 after the Federal Underground Injection Control regulations were enacted by United States Environmental Protection Agency (USEPA) making it necessary to properly close the wells. The work is being performed for the United States Department of Energy Oak Ridge Operations (DOE ORO). The project team is using the philosophy of minimum waste generation and the principles of ALARA (As Low As Reasonably Achievable) as key project goals to minimize personnel and equipment exposure, waste generation, and project costs. Achievement of these goals was demonstrated by the introduction of several new pieces of custom designed well plugging and abandonment equipment that were tested and used effectively during field operations. Highlights of the work performed and the equipment used are presented.

Whiteside, R.; Pawlowicz, R.; Whitehead, L.; Arnseth, R.

2002-02-25

211

DEVELOPMENT OF DOWNHOLE EQUIPMENT FOR BEATRICE ELECTRICAL SUBMERSIBLE PUMP (ESP) WELLS 1981 - 1985  

Microsoft Academic Search

The Beatrice Field in the North Sea relies exclusively for production on artificial lift, using electrical submersible pumps (ESP's). Beatrice came on stream during September, 1981 from 3 wells on the 'A' platform. 'B' and 'C' platforms were completed during 1984\\/1985 and there are now 22 production wells, each with an ESP and 12 water injection wells for pressure maintenance.

J. K. Brown; D. Bills

1985-01-01

212

Geophysical Logs, Specific Capacity, and Water Quality of Four Wells at Rogers Mechanical (former Tate Andale) Property, North Penn Area 6 Superfund Site, Lansdale, Pennsylvania, 2006-07  

USGS Publications Warehouse

As part of technical assistance to the U.S. Environmental Protection Agency (USEPA) in the remediation of properties on the North Penn Area 6 Superfund Site in Lansdale, Pa., the U.S. Geological Survey (USGS) in 2006-07 collected data in four monitor wells at the Rogers Mechanical (former Tate Andale) property. During this period, USGS collected and analyzed borehole geophysical and video logs of three new monitor wells (Rogers 4, Rogers 5, and Rogers 6) ranging in depth from 80 to 180 feet, a borehole video log and additional heatpulse-flowmeter measurements (to quantify vertical borehole flow) in one existing 100-foot deep well (Rogers 3S), and water-level data during development of two wells (Rogers 5 and Rogers 6) to determine specific capacity. USGS also summarized results of passive-diffusion bag sampling for volatile organic compounds (VOCs) in the four wells. These data were intended to help understand the groundwater system and the distribution of VOC contaminants in groundwater at the property.

Senior, Lisa A.; Bird, Philip H.

2010-01-01

213

Fracture density estimation from core and conventional well logs data using artificial neural networks: The Cambro-Ordovician reservoir of Mesdar oil field, Algeria  

NASA Astrophysics Data System (ADS)

Fracture density estimation is an indisputable challenge in fractured reservoir characterization. Traditional techniques of fracture characterization from core data are costly, time consuming, and difficult to use for any extrapolation to non-cored wells. The aim of this paper is to construct a model able to predict fracture density from conventional well logs calibrated to core data by using artificial neural networks (ANNs). This technique was tested in the Cambro-Ordovician clastic reservoir from Mesdar oil field (Saharan platform, Algeria). For this purpose, 170 cores (2120.14 m) from 17 unoriented wells have been studied in detail. Seven training algorithms and eight neuronal network architectures were tested. The best architecture is a four layered [6-16-3-1] network model with: a six-neuron input layer (Gamma ray, Sonic interval transit time, Caliper, Neutron porosity, Bulk density logs and core depth), two hidden layers; the first hidden layer has 16 neurons, the second one has three neurons. And a one-neuron output layer (fracture density). The results based on 8094 data points from 13 wells show the excellent prediction ability of the conjugate gradient descent (CGD) training algorithm (R-squared = 0.812).The cross plot of measured and predicted values of fracture density shows a very high coefficient of determination of 0.848. Our studies have demonstrated a good agreement between our neural network model prediction and core fracture measurements. The results are promising and can be easily extended in other similar neighboring naturally fractured reservoirs.

Zazoun, Réda Samy

2013-07-01

214

Logs of wells and boreholes drilled during hydrogeologic studies at Lawrence Livermore National Laboratory Site 300, January 1, 1982--June 30, 1988: January 1, 1982 through June 30, 1988  

SciTech Connect

We present the hydrogeologic well logs for monitor wells and exploratory boreholes drilled at Lawrence Livermore National Laboratory (LLNL) Site 300 between the beginning of environmental investigations in June 1982 and the end of June 1988. These wells and boreholes were drilled as part of studies made to determine the horizontal and vertical distribution of volatile organic compounds (VOCs), high explosive (HE) compounds, and tritium in soil, rock, and ground water at Site 300. The well logs for 293 installations comprise the bulk of this report. We have prepared summaries of Site 300 geology and project history that provide a context for the well logs. Many of the logs in this report have also been published in previous topical reports, but they are nevertheless included in order to make this report a complete record of the wells and boreholes drilled prior to July 1988. A commercially available computer program, LOGGER has been used since late 1985 to generate these logs. This report presents details of the software programs and the hardware used. We are presently completing a project to devise a computer-aided design (CAD) system to produce hydrogeologic cross sections and fence diagrams, utilizing the digitized form of these logs. We find that our system produces publication-quality well and exploratory borehole logs at a lower cost than that of logs drafted by traditional methods.

Toney, K.C.; Crow, N.B.

1988-01-01

215

The automatic interpretation of natural ?-rays in well logging at the phosphatic deposits in the Palmyra region in Syria  

Microsoft Academic Search

A new methodology has been introduced for the automatic interpretation of natural ?-rays in wells and pits, using numerical analysis. This approach is aimed at the accurate determination of radioactive lithology levels, the thickness and the radioactive intensities. A model of four main radioactive types (K, H, A and Q) has been suggested in the prospecting region for phosphatic deposits

J Asfahani; Z Kamarji

1996-01-01

216

Elemental concentration logging with a germanium spectrometer  

SciTech Connect

The German deep-well project is currently drilling a scientific well in northeastern Bavaria at the intersection of the African and Northern European tectonic plates. This well is scheduled to be drilled to a depth of {approximately}10 km to study the geochemical processes involved in the alteration of minerals under high temperature and pressure. As an initial stage in this project, a well was drilled to a depth of 4 km within 200 m of the site selected for the deep well. This well was fully cored and extensively logged with both commercial and experimental logging systems. Cores, as well as cuttings and fluids, were extensively analyzed in a well-site laboratory established specifically for that purpose. One of the experimental logging systems run in the 4-km well was a gamma-ray spectrometer that used a {sup 252}Cf source for delayed activation measurements and a neutron generator that produces 14-MeV neutrons for thermal neutron-capture gamma-ray measurements. There were two primary goals of this project. The first was to confirm the validity of elemental concentration determinations from commercial logging equipment, based on NaI(Tl) detectors, in this crystalline rock environment. The commercial equipment determines the elements: aluminum, silicon, sulfur, calcium, titanium, iron, gadolinium, potassium, thorium, and uranium. The second was to determine additional elemental concentrations that can be used to enhance the geo-chemical studies of the crystalline rock mineralogy.

Peterson, C.A.; Schweitzer, J.S. (Schlumberger-Doll Research Center, Ridgefield, CT (United States)); Draxler, J.K.

1991-11-01

217

Geophysical Logs, Aquifer Tests, and Water Levels in Wells in and Near the North Penn Area 7 Superfund Site, Upper Gwynedd Township, Montgomery County, Pennsylvania, 2002-2006  

USGS Publications Warehouse

Ground water in the vicinity of several industrial facilities in Upper Gwynedd Township and Lansdale Borough, Montgomery County, Pa., is contaminated with several volatile organic compounds (VOCs). The 2-square-mile area was placed on the National Priorities List as the North Penn Area 7 Superfund Site by the U.S. Environmental Protection Agency (USEPA) in 1989. The U.S. Geological Survey (USGS) conducted geophysical logging, aquifer testing, water-level monitoring, and streamflow measurements in the vicinity of North Penn Area 7 from October 2002 through December 2006. This followed work that began in 2000 to assist the USEPA in developing an understanding of the hydrogeologic framework in the area as part of the USEPA Remedial Investigation. The study area is underlain by Triassic- and Jurassic-age sandstones, siltstones, and shales of the Lockatong Formation and the Brunswick Group. Regionally, these rocks strike northeast and dip to the northwest. The sequence of rocks form fractured-rock aquifers that act as a set of confined to semi-confined layered aquifers of differing permeabilities. The aquifers are recharged by precipitation and discharge to streams and wells. The Wissahickon Creek headwaters are less than 1 mile northeast of the study area. This stream flows southwest approximately parallel to strike and bisects North Penn Area 7. Ground water is pumped in the vicinity of North Penn Area 7 for industrial use and public supply. The USGS collected geophysical logs for 42 wells that ranged in depth from 40 to 477 ft. Aquifer-interval-isolation testing was done in 17 of the 42 wells, for a total of 122 zones tested. A multiple-well aquifer test was conducted by monitoring the response of 14 wells to pumping and shutdown of a 600-ft deep production well in November-December 2004. In addition, water levels were monitored continuously in four wells in the area from October 2002 through September 2006, and streamflow was measured quarterly at two sites on Wissahickon Creek from December 2002 through September 2005. Geophysical logging identified water-bearing zones associated with high-angle fractures and bedding-plane openings throughout the depth of the boreholes. Heatpulse-flowmeter measurements under non-pumping, ambient conditions in 16 wells greater than 200 ft in depth indicated that borehole flow, where detected, was only upward in 2 wells and only downward in 5 wells. In nine wells, both upward and downward flow were measured. Geologic structure and pumping in the area affect the spatial distribution of vertical gradients. Heatpulse-flowmeter measurements under pumping conditions were used to identify the most productive intervals in wells. Correlation of natural-gamma-ray logs indicated bedding in the area probably strikes about 45 to 65 degrees northeast and dips about 9 degrees northwest. Aquifer intervals isolated by inflatable packers in 17 wells were pumped to test productivity of water-bearing zones and to collect samples to determine chemical quality of water produced from the interval. Interval-isolation testing confirmed the vertical hydraulic gradients indicated by heatpulse-flowmeter measurements. The specific capacities of the 122 isolated intervals ranged over about three orders of magnitude, from 0.01 to 10.6 gallons per minute per foot, corresponding to calculated transmissivities of 1.2 to 2,290 feet squared per day. Intervals adjacent to isolated pumped intervals commonly showed little response to pumping of the isolated zone. The presence of vertical hydraulic gradients and lack of adjacent-interval response to pumping in isolated intervals indicate a limited degree of vertical hydraulic connection between the aquifer sections tested. Differences were apparent in inorganic water quality of water from isolated intervals, including pH, specific conductance, and dissolved oxygen. Concentrations of most VOC contaminants in most wells with predominantly upward vertical gradients were g

Senior, Lisa A.; Conger, Randall W.; Bird, Philip H.

2008-01-01

218

Logging evaluation method of low resistivity reservoir—A case study of well block DX12 in Junggar basin  

Microsoft Academic Search

The Hutubi (???) River reservoir of well block DX12 is a lithologic hydrocarbon reservoir that is under tectonic settings.\\u000a The main oil-bearing sand body in this area is thin and has a poor transverse connectivity. Because of the complexity of the\\u000a oil-water relationship, the oil reservoir presents a low resistivity feature, which brings great difficulties to hydrocarbon\\u000a reservoir identification. This

Liqun Chen; Changchun Zou; Zhonghao Wang; Haijun Liu; Shuang Yao; Dong Chen

2009-01-01

219

Estimation of biogenic silica contents in marine sediments using seismic and well log data: Sediment Drift 7, Antarctica  

Microsoft Academic Search

Petrophysical properties (wet bulk density, porosity, P-wave velocity) are used to predict biogenic silica contents along\\u000a a seismic reflection profile that ties two well sites, 1095 and 1096, drilled by Ocean Drilling Program (ODP) Leg 178 on sediment\\u000a drifts on the Pacific continental margin of the Antarctic Peninsula. The biogenic silica contents along the seismic reflection\\u000a profile were estimated on

R. C. Neagu; U. Tinivella; V. Volpi; M. Rebesco; A. Camerlenghi

2009-01-01

220

Geophysical logs and water-quality data collected for boreholes Kimama-1A and -1B, and a Kimama water supply well near Kimama, southern Idaho  

USGS Publications Warehouse

In September 2010, a research consortium led by scientists from Utah State University began drilling the first of three continuously cored boreholes on the Snake River Plain in southern Idaho. The goals of this effort, the Snake River Scientific Drilling Project, are to study the interaction between the Earth's crust and mantle, to identify potential geothermal energy sources, and to track the evolution of the Yellowstone hotspot on the Snake River Plain. The first borehole, located near Kimama, Idaho, is about 50 miles southwest of the U.S. Department of Energy's Idaho National Laboratory. Because geohydrologic data are scarce for that area of the central Snake River Plain, the Kimama borehole, completed in January 2011, provided a unique opportunity to collect geophysical and water-chemistry data from the eastern Snake River Plain aquifer system, downgradient of the laboratory. Therefore, in conjunction with the Snake River Scientific Drilling Project, scientists from the U.S. Geological Survey's Idaho National Laboratory Project Office conducted geophysical logging and collected water samples at the Kimama site. Wireline geophysical logs were collected for the diverging borehole, Kimama-1A and -1B, from land surface to 976 and 2,498 feet below land surface (BLS), respectively. Water samples were collected from Kimama-1A at depths near 460 and 830 feet BLS, and from the Kimama Water Supply (KWS) well located about 75 feet away. Geophysical log data included a composite of natural gamma, neutron, gamma-gamma dual density, and gyroscopic analysis for boreholes Kimama-1A and -1B. Geophysical logs depicted eight sediment layers (excluding surficial sediment) ranging from 4 to 60 feet in thickness. About 155 individual basalt flows were identified, ranging from less than 3 feet to more than 175 feet in thickness (averaging 15 feet) for borehole Kimama-1B (0 to 2,498 feet BLS). Sediment and basalt contacts were selected based on geophysical traces and were confirmed with visual inspection of core photographs. Temperature logs from the water table surface (about 260 feet BLS) to the bottom of borehole Kimama-1B (2,498 feet BLS) were nearly isothermal, ranging from about 62 to 64 degrees Fahrenheit. Gyroscopic data revealed that borehole Kimama-1B begins to separate from borehole Kimama-1A near a depth of 676 feet BLS. Drillhole azimuth and horizontal deviation at total logged depth for boreholes Kimama-1A and -1B were 172.6 and 188.3 degrees and 25.9 and 82.0 feet, respectively. Water samples were collected and analyzed for common ions; selected trace elements; nutrients; isotopes of hydrogen, oxygen, and carbon; and selected radionuclides. One set of water samples was collected from the KWS well and the two other sample sets were collected from borehole Kimama-1A near 460 and 830 feet BLS. With one exception, data for all three zones sampled near Kimama generally indicated that the water chemistry was similar. The exception was found in the deepest zone in borehole Kimama-1A (830 feet BLS) where concentrations probably were affected by the drilling mud. A comparison of the inorganic, organic, and stable chemistry data between the KWS well and the 460-foot zone in borehole Kimama-1A indicated similar chemistry of the aquifer water, except for some variability with nitrate plus nitrite, orthophosphate, iron, zinc, and carbon-14. Radionuclide concentrations were either less than reporting levels or at background levels for the eastern Snake River Plain aquifer.

Twining, Brian V.; Bartholomay, Roy C.

2011-01-01

221

Spin Dynamics of Carr-Purcell-Meiboom-Gill-like Sequences in Grossly Inhomogeneous B0 and B1 Fields and Application to NMR Well Logging  

NASA Astrophysics Data System (ADS)

The spin dynamics for Carr-Purcell-Meiboom-Gill-like sequences is analyzed in grossly inhomogeneous B0 and B1 fields. This problem is important for many applications, especially when the bandwidth of the signal is excitation limited. Examples include stray-field NMR or inside-out NMR probes used in well logging. The amplitudes of the first few echoes exhibit a characteristic transient behavior but quickly approach a smooth asymptotic behavior. For simple Hamiltonians without scalar or dipolar couplings, the evolution of a refocusing subcycle for a given isochromat is described by a rotation. Simple expressions for the signal of the Nth echo are derived in terms of these effective rotations that have a simple geometrical interpretation. It is shown that the asymptotic behavior is controlled by the direction of the axis of these effective rotations and the signal is dominated by magnetization "spin-locked" to the rotation axis. The phase of the signal is independent of the details of the field inhomogeneities. Relaxation in inhomogeneous fields leads to a signal decay that is in general nonexponential with an initial decay rate that is a weighted sum of T-11 and T-12. At long times, the echo amplitudes decay to a finite value. Phase cycling eliminates this offset. The effect of diffusion is also studied. This analysis has been applied to an inside-out NMR well logging apparatus. Good quantitative agreement is found between measurements and calculations that are based on the measured B0 and B1 field maps.

Hürlimann, M. D.; Griffin, D. D.

2000-03-01

222

Preliminary design of a special casing joint for a well equipped twin horizontal drainholes in the Oxnard field  

SciTech Connect

The Oxnard field is presently under production,with a typical average monthly oil production of about 70,000 B, of which the Vaca Tar sand represents more than half.It is Unitized and operated under cyclic steam injection.The hot Tar and produced water are lifted to the surface with rod pumps equipped for injection of a diluent. The produced WOR is about 2.5 and the GOR is about 150 scf/B. The Vaca Tar sand originally contained about 400 million STB. The estimated recoverable reserve under full-scale cyclic steam injection is 100 to 120 Million STB. Under steamflood, it might reach 240 million STB. The objectives of this field test are: (1) increase well productivity by using a vertical well equipped with twin horizontal drainholes, each of about 1,000 ft. reach; (2) maximize the well draw-down by locating the horizontal wells near the base of the sand layer; (3) reduce capital cost by using twin drainholes connected to the same vertical cased well; (4) reduce operating expenses by eliminating the need for a service rig to pull-out the rods and pump before each steam injection cycle; and (5) be adaptable to other operating modes.

Not Available

1993-12-31

223

Summary of hydraulic data and abridged lithologic log of ground-water test well 6(J-13) Jackass Flats, Nevada Test Site, Nye County, Nevada. Technical letter NTS-50  

Microsoft Academic Search

This technical letter summarizes the results of drilling groundwater test well 6 and presents an abridged lithologic log, well construction information, and results of hydraulic tests made in the well. Test well 6 (designated well J-13 by NASA) is one of several wells drilled in support of the Long Range Program of the US Geological Survey to study the geology

A. C. Doyle; G. L. Meyer

1963-01-01

224

Preliminary Fracture Description from Core, Lithological Logs, and Borehole Geophysical Data in Slimhole Wells Drilled for Project Hotspot: the Snake River Geothermal Drilling Project  

NASA Astrophysics Data System (ADS)

The Snake River Geothermal Drilling Project (Project Hotspot) seeks to assess the potential for geothermal energy development in the Snake River Plain (SRP), Idaho. Three deep slimhole wells are drilled at the Kimama, Kimberly, and Mountain Home sites in the central SRP. The Kimama and Kimberly wells are complete and the Mountain Home well is in progress. Total depth at Kimama is 1,912 m while total depth at Kimberly is 1,958 m. Mountain Home is expected to reach around 1,900 m. Full core is recovered and complete suites of wireline borehole geophysical data have been collected at both Kimama and Kimberly sites along with vertical seismic profiles. Part of the geothermal assessment includes evaluating the changes in the nature of fractures with depth through the study of physical core samples and analysis of the wireline geophysical data to better understand how fractures affect permeability in the zones that have the potential for geothermal fluid migration. The fracture inventory is complete for the Kimama borehole and preliminary analyses indicate that fracture zones are related to basaltic flow boundaries. The average fracture density is 17 fractures/3 m. The maximum fracture density is 110 fractures/3 m. Fracture density varies with depth and increases considerably in the bottom 200 m of the well. Initial indications are that the majority of fractures are oriented subhorizontally but a considerable number are oriented subvertically as well. We expect to statistically evaluate the distribution of fracture length and orientation as well as analyze local alteration and secondary mineralization that might indicate fluid pathways that we can use to better understand permeability at depth in the borehole. Near real-time temperature data from the Kimama borehole indicate a temperature gradient of 82°C/km below the base of the Snake River Plain aquifer at a depth of 960 m bgs. The measured temperature at around 1,400 m depth is 55°C and the projected temperature at 2,000 m depth is 102°C. The rock types at Kimama and Kimberly are primarily basalt and rhyolite, respectively, with interbedded thin sedimentary layers. We identify anomalies in the physical properties of igneous rocks using porosity logs (neutron and acoustic), lithology logs (gamma ray and magnetic susceptibility) and fracture/saturation logs (televiewer and electrical resistivity). The core will be used to constrain the geophysical data and confirm the ability to identify permeability in fracture zones and saturated zones through analysis of the wireline log data. The matrix porosity of these igneous lithologies is near zero aside from porosity from vugs and vesicles. However, open and sealed fractures indicate that mineralizing fluids form connected pathways in the rock. Core samples show a series of alteration phases, including amygdaloidal fine-grained calcite and secondary clays. The geophysical data will be used to predict anomalies in lithology and identify open fractures and saturated zones with high permeability.

Kessler, J. A.; Evans, J. P.; Shervais, J. W.; Schmitt, D.

2011-12-01

225

Shale compaction and sonic logs  

US Patent & Trademark Office Database

A method of calculating a theoretical sonic log from an ideal sonic log and resistivity data. The method involves calculating the ideal sonic log assuming a shale sediment and using available data from a well or the surrounding region. Resistivity data is used to correct the ideal sonic log for departures from the shale sediment assumption. The calculated theoretical sonic log may then be used to calibrate an experimental log and to replace low confidence segments of the experimental log. The method allows useful information to be derived for wells previously considered uneconomical.

2002-06-25

226

Yucatan Subsurface Stratigraphy from Geophysical Data, Well Logs and Core Analyses in the Chicxulub Impact Crater and Implications for Target Heterogeneities  

NASA Astrophysics Data System (ADS)

Asymmetries in the geophysical signature of Chicxulub crater are being evaluated to investigate on effects of impact angle and trajectory and pre-existing target structural controls for final crater form. Early studies interpreted asymmetries in the gravity anomaly in the offshore sector to propose oblique either northwest- and northeast-directed trajectories. An oblique impact was correlated to the global ejecta distribution and enhanced environmental disturbance. In contrast, recent studies using marine seismic data and computer modeling have shown that crater asymmetries correlate with pre-existing undulations of the Cretaceous continental shelf, suggesting a structural control of target heterogeneities. Documentation of Yucatan subsurface stratigraphy has been limited by lack of outcrops of pre-Paleogene rocks. The extensive cover of platform carbonate rocks has not been affected by faulting or deformation and with no rivers cutting the carbonates, information comes mainly from the drilling programs and geophysical surveys. Here we revisit the subsurface stratigraphy in the crater area from the well log data and cores retrieved in the drilling projects and marine seismic reflection profiles. Other source of information being exploited comes from the impact breccias, which contain a sampling of disrupted target sequences, including crystalline basement and Mesozoic sediments. We analyze gravity and seismic data from the various exploration surveys, including multiple Pemex profiles in the platform and the Chicxulub experiments. Analyses of well log data and seismic profiles identify contacts for Lower Cretaceous, Cretaceous/Jurassic and K/Pg boundaries. Results show that the Cretaceous continental shelf was shallower on the south and southwest than on the east, with emerged areas in Quintana Roo and Belize. Mesozoic and upper Paleozoic sediments show variable thickness, possibly reflecting the crystalline basement regional structure. Paleozoic and Precambrian basement outcrops are located farther to the southeast in Belize and northern Guatemala. Inferred shelf paleo-bathymetry supports existence of a sedimentary basin extending to the northeast, where crater rim and terrace zones are subdued in the seismic images.

Canales, I.; Fucugauchi, J. U.; Perez-Cruz, L. L.; Camargo, A. Z.; Perez-Cruz, G.

2011-12-01

227

Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Sites at Slick Rock, Colorado: Appendix B to Attachment 3, Lithologic logs and monitor well construction information. Final report  

SciTech Connect

This volume contains lithology logs and monitor well construction information for: NC processing site; UC processing site; and Burro Canyon disposal site. This information pertains to the ground water hydrology investigations which is attachment 3 of this series of reports.

NONE

1995-09-01

228

Sandstone and shale compaction curves derived from sonic and gamma ray logs in offshore wells, North Slope, Alaska; parameters for basin modeling  

USGS Publications Warehouse

Representative compaction curves for the principle lithologies are essential input for reliable models of basin history. Compaction curves influence estimates of maximum burial and erosion. Different compaction curves may produce significantly different thermal histories. Default compaction curves provided by basin modeling packages may or may not be a good proxy for the compaction properties in a given area. Compaction curves in the published literature span a wide range, even within one lithology, e.g., sandstone (see Panel 3). An abundance of geophysical well data for the North Slope, from both government and private sources, provides us with an unusually good opportunity to develop compaction curves for the Cretaceous-Tertiary Brookian sandstones, siltstones, and shales. We examined the sonic and gamma ray logs from 19 offshore wells (see map), where significant erosion is least likely to have occurred. Our data are primarily from the Cretaceous-Tertiary Brookian sequence and are less complete for older sequences. For each well, the fraction of shale (Vsh) at a given depth was estimated from the gamma ray log, and porosity was computed from sonic travel time. By compositing porosities for the near-pure sand (Vsh99%)from many individual wells we obtained data over sufficient depth intervals to define sandstone and shale 'master' compaction curves. A siltstone curve was defined using the sonic-derived porosities for Vsh values of 50%. These compaction curves generally match most of the sonic porosities with an error of 5% or less. Onshore, the curves are used to estimate the depth of maximum burial at the end of Brookian sedimentation. The depth of sonic-derived porosity profiles is adjusted to give the best match with the 'master' compaction curves. The amount of the depth adjustment is the erosion estimate. Using our compaction curves, erosion estimates on the North Slope range from zero in much of the offshore, to as much as 1500 ft along the coast, and to more than 10,000 ft in the foothills (Panel 3). Compaction curves provide an alternative to vitrinite reflectance for estimating erosion. Vitrinite reflectance data are often very sparse in contrast to well log data and are subject to inconsistencies when measurements are made by different labs. The phenomenon of 'recycling' can also make the reflectance values of dispersed vitrinite problematic for quantifying erosion. Recycling is suspected in dispersed vitrinite in North Slope rocks, particularly in the younger, Cretaceous-Tertiary section. The compaction curves defined here are being integrated into our burial history and thermal models to determine the timing of source rock maturation. An example on Panel 3 shows the results of calculating the maturity of the Shublik Fm. at the Tulaga well using two different sets of shale and siltstone compaction curves. Finally, accurate compaction curves improve a model's ability to realistically simulate the pressure regime during burial, including overpressures.

Rowan, Elisabeth L.; Hayba, Daniel O.; Nelson, Philip H.; Burns, W. Matthew; Houseknecht, David W.

2003-01-01

229

3. Log bunkhouse (far left), log chicken house (left of ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Log bunkhouse (far left), log chicken house (left of center), equipment shed (center), and workshop (far right). View to northwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

230

Transaction Logging.  

ERIC Educational Resources Information Center

Discusses the use of transaction logging in Okapi-related projects to allow search algorithms and user interfaces to be investigated, evaluated, and compared. A series of examples is presented, illustrating logging software for character-based and graphical user interface systems, and demonstrating the usefulness of relational database management…

Jones, S.; And Others

1997-01-01

231

Interpretation of Flow Logs from Nevada Test Site Boreholes to Estimate Hydraulic conductivity Using Numerical Simulations Constrained by Single-Well Aquifer Tests  

SciTech Connect

Hydraulic conductivities of volcanic and carbonate lithologic units at the Nevada Test Site were estimated from flow logs and aquifer-test data. Borehole flow and drawdown were integrated and interpreted using a radial, axisymmetric flow model, AnalyzeHOLE. This integrated approach is used because complex well completions and heterogeneous aquifers and confining units produce vertical flow in the annular space and aquifers adjacent to the wellbore. AnalyzeHOLE simulates vertical flow, in addition to horizontal flow, which accounts for converging flow toward screen ends and diverging flow toward transmissive intervals. Simulated aquifers and confining units uniformly are subdivided by depth into intervals in which the hydraulic conductivity is estimated with the Parameter ESTimation (PEST) software. Between 50 and 150 hydraulic-conductivity parameters were estimated by minimizing weighted differences between simulated and measured flow and drawdown. Transmissivity estimates from single-well or multiple-well aquifer tests were used to constrain estimates of hydraulic conductivity. The distribution of hydraulic conductivity within each lithology had a minimum variance because estimates were constrained with Tikhonov regularization. AnalyzeHOLE simulated hydraulic-conductivity estimates for lithologic units across screened and cased intervals are as much as 100 times less than those estimated using proportional flow-log analyses applied across screened intervals only. Smaller estimates of hydraulic conductivity for individual lithologic units are simulated because sections of the unit behind cased intervals of the wellbore are not assumed to be impermeable, and therefore, can contribute flow to the wellbore. Simulated hydraulic-conductivity estimates vary by more than three orders of magnitude across a lithologic unit, indicating a high degree of heterogeneity in volcanic and carbonate-rock units. The higher water transmitting potential of carbonate-rock units relative to volcanic-rock units is exemplified by the large difference in their estimated maximum hydraulic conductivity; 4,000 and 400 feet per day, respectively. Simulated minimum estimates of hydraulic conductivity are inexact and represent the lower detection limit of the method. Minimum thicknesses of lithologic intervals also were defined for comparing AnalyzeHOLE results to hydraulic properties in regional ground-water flow models.

Garcia, C. Amanda; Halford, Keith J.; Laczniak, Randell J.

2010-02-12

232

Mud logging handbook  

SciTech Connect

The author provides a review of all available types and levels of well site services which can be performed in the mud logging unit. For each service, an explanation is given of how, how well, and when the gathered data may be applied. The value of mud logging services and data are assessed on the basis of their usefulness, quality, and timeliness in the chronology of drilling optimization and formation evaluation.

Whittaker, A.

1990-01-01

233

Field project to obtain pressure core, wireline log, and production test data for evaluation of CO/sub 2/ flooding potential. Texas Pacific Bennett Ranch Unit well No. 310, Wasson (San Andres) Field, Yoakum County, Texas  

SciTech Connect

The coring, logging and testing of Bennett Ranch Unit well No. 310 was a cooperative effort between Texas Pacific, owner of the well, and Gruy Federal, Inc. The requirements of the contract, which are summarized in Enclosure 1, Appendix A, include drilling and coring activities. The pressure-coring and associated logging and testing programs in selected wells are intended to provide data on in-situ oil saturation, porosity and permeability distribution, and other data needed for resource characterization of fields and reservoirs in which CO/sub 2/ injection might have a high probability of success. This report presents detailed information on the first such project. This project demonstrates the usefulness of integrating pressure core, log and production data to realistically evaluate a reservoir for carbon dioxide flood. The engineering of tests and analysis of such experimental data requires original thinking, but the reliability of the results is higher than data derived from conventional tests.

Swift, T.E.; Goodrich, J.H.; Kumar, R.M.; McCoy, R.L.; Wilhelm, M.H.; Glascock, M.R.

1982-01-01

234

Log Tape  

NSDL National Science Digital Library

In this activity students construct Log Tapes calibrated in base-ten exponents, then use them to derive relationships between base-ten logs (exponents) and antilogs (ordinary numbers).  This is activity B1 in the "Far Out Math" educator's guide. Lessons in the guide include activities in which students measure,compare quantities as orders of magnitude, become familiar with scientific notation, and develop an understanding of exponents and logarithms using examples from NASA's GLAST mission. These are skills needed to understand the very large and very small quantities characteristic of astronomical observations. Note: In 2008, GLAST was renamed Fermi, for the physicist Enrico Fermi.

235

Statistical analysis of correlation of porosity and permeability determinations from well cuttings using a portable pNMR apparatus with conventional core analysis and wireline log readings  

SciTech Connect

The porosity-permeability (P-K) analyzer is a field-portable device that uses the principle of pulsed nuclear magnetic resonance to determine the content of hydrogen nuclei present in the free and bound water in rock samples. Using a simple dual-water model, these values may be used to calculate total porosity, free fluid index, and permeability index. The principle of measurements is such as to require relatively small sample volumes and reliable results can be obtained from well-cuttings samples or 3-mm diameter core plugs. Results from the P-K analyzer are responsive to total fluid-filled pore space in the rock, although it is possible to distinguish free, i.e., movable, fluid from bound fluid, i.e., at grain boundaries or within restricted pores and in argillaceous rocks. The P-K response is entirely independent of formation lithology, mineralogy, or salinity or pore waters and is not appreciably affected by the presence of light oils. The presence of free or dissolved gases in the sample will have a significant effect on response. However, samples are brine flushed and aspirated in preparation for analysis in order to remove this effect. The authors see, from these differences, that results from the P-K method cannot be expected to show a direct one-to-one correlation with those from conventional core analysis or the wireline density or neutron logging tools. A statistical analysis is presented using data from each of the analytical methods and types and conditions of sample. A strong correlation is demonstrated both visually and statistically, thereby providing verification of the P-K method and facilitating its use alongside data previously obtained by more conventional methods.

Nigh, E.L.; Whittaker, A.H.; Macpherson, J.D.

1985-04-01

236

Artificial neural network modeling and cluster analysis for organic facies and burial history estimation using well log data: A case study of the South Pars Gas Field, Persian Gulf, Iran  

NASA Astrophysics Data System (ADS)

Intelligent and statistical techniques were used to extract the hidden organic facies from well log responses in the Giant South Pars Gas Field, Persian Gulf, Iran. Kazhdomi Formation of Mid-Cretaceous and Kangan-Dalan Formations of Permo-Triassic Data were used for this purpose. Initially GR, SGR, CGR, THOR, POTA, NPHI and DT logs were applied to model the relationship between wireline logs and Total Organic Carbon (TOC) content using Artificial Neural Networks (ANN). The correlation coefficient (R2) between the measured and ANN predicted TOC equals to 89%. The performance of the model is measured by the Mean Squared Error function, which does not exceed 0.0073. Using Cluster Analysis technique and creating a binary hierarchical cluster tree the constructed TOC column of each formation was clustered into 5 organic facies according to their geochemical similarity. Later a second model with the accuracy of 84% was created by ANN to determine the specified clusters (facies) directly from well logs for quick cluster recognition in other wells of the studied field. Each created facies was correlated to its appropriate burial history curve. Hence each and every facies of a formation could be scrutinized separately and directly from its well logs, demonstrating the time and depth of oil or gas generation. Therefore potential production zone of Kazhdomi probable source rock and Kangan- Dalan reservoir formation could be identified while well logging operations (especially in LWD cases) were in progress. This could reduce uncertainty and save plenty of time and cost for oil industries and aid in the successful implementation of exploration and exploitation plans.

Alizadeh, Bahram; Najjari, Saeid; Kadkhodaie-Ilkhchi, Ali

2012-08-01

237

Reviews Book: Enjoyable Physics Equipment: SEP Colorimeter Box Book: Pursuing Power and Light Equipment: SEP Bottle Rocket Launcher Equipment: Sciencescope GLE Datalogger Equipment: EDU Logger Book: Physics of Sailing Book: The Lightness of Being Software: Logotron Insight iLog Studio iPhone Apps Lecture: 2010 IOP Schools and Colleges Lecture Web Watch  

NASA Astrophysics Data System (ADS)

WE RECOMMEND Enjoyable Physics Mechanics book makes learning more fun SEP Colorimeter Box A useful and inexpensive colorimeter for the classroom Pursuing Power and Light Account of the development of science in the 19th centuary SEP Bottle Rocket Launcher An excellent resource for teaching about projectiles GLE Datalogger GPS software is combined with a datalogger EDU Logger Remote datalogger has greater sensing abilities Logotron Insight iLog Studio Software enables datlogging, data analysis and modelling iPhone Apps Mobile phone games aid study of gravity WORTH A LOOK Physics of Sailing Book journeys through the importance of physics in sailing The Lightness of Being Study of what the world is made from LECTURE The 2010 IOP Schools and Colleges Lecture presents the physics of fusion WEB WATCH Planet Scicast pushes boundaries of pupil creativity

2010-09-01

238

Log Ruler  

NSDL National Science Digital Library

In this activity students construct Log Rulers, finely calibrated in base-10 exponents and numbers (logs and antilogs). They practice reading these scales as accurately as possible, listing all certain figures plus one uncertain figure.  This is activity D1 in the "Far Out Math" educator's guide. Lessons in the guide include activities in which students measure,compare quantities as orders of magnitude, become familiar with scientific notation, and develop an understanding of exponents and logarithms using examples from NASA's GLAST mission. These are skills needed to understand the very large and very small quantities characteristic of astronomical observations. Note: In 2008, GLAST was renamed Fermi, for the physicist Enrico Fermi.

239

Geological & Geophysical findings from seismic, well log and core data for marine gas hydrate deposits at the 1st offshore methane hydrate production test site in the eastern Nankai Trough, offshore Japan: An overview  

NASA Astrophysics Data System (ADS)

In order to evaluate productivity of gas from marine gas hydrate by the depressurization method, Japan Oil, Gas and Metals National Corporation is planning to conduct a full-scale production test in early 2013 at the AT1 site in the north slope of Daini-Atsumi Knoll in the eastern Nankai Trough, Japan. The test location was determined using the combination of detailed 3D seismic reflection pattern analysis, high-density velocity analysis, and P-impedance inversion analysis, which were calibrated using well log data obtained in 2004. At the AT1 site, one production well (AT1-P) and two monitoring wells (AT1-MC and MT1) were drilled from February to March 2012, followed by 1 coring well (AT1-C) from June to July 2012. An extensive logging program with logging while drilling (LWD) and wireline-logging tools, such as GeoVISION (resistivity image), EcoScope (neutron/density porosity, mineral spectroscopy etc.), SonicScanner (Advanced Sonic tool), CMR/ProVISION (Nuclear Magnetic Resonance Tools), XPT (formation pressure, fluid mobility), and IsolationScanner (ultrasonic cement evaluation tools) was conducted at AT1-MC well to evaluate physical reservoir properties of gas hydrate-bearing sediments, to determine production test interval in 2013, and to evaluate cement bonding. Methane hydrate concentrated zone (MHCZ) confirmed by the well logging at AT1-MC was thin turbidites (tens of centimeters to few meters) with 60 m of gross thickness, which is composed of lobe type sequences in the upper part of it and channel sand sequences in the lower part. The gross thickness of MHCZ in the well is thicker than previous wells in 2004 (A1, 45 m) located around 150 m northeast, indicating that the prediction given by seismic inversion analysis was reasonable. Well-to-well correlation between AT1-MC and MT1 wells within 40 m distance exhibited that lateral continuity of these sand layers (upper part of reservoir) are fairly good, which representing ideal reservoir for the production test. The XPT measurement results showed approximately 0.1 to several mD of water permeability in both the hydrate-bearing formation and seal formation, although there are some variations in measured values. However, the comparison of these results with permeability estimated by NMR log showed significant discrepancy (more than one order of difference), which suggests that it is necessary to have further investigation considering the difference in scale, measurement direction (Kh or Kv), and calibration methodology by pressure core data. In order to obtain basic reservoir/seal properties for the well log calibration within and above production test interval, pressure coring using Hybrid Pressure Coring System (Hybrid PCS) and also non-destructive core analysis onboard using Pressure Core Analysis and Transfer System (PCATS) were conducted for 60 m interval in AT1-C, which located about 10 m northeast of AT1-MC. Finally, integrated reservoir characterization based on well-log and pressure core data was conducted to predict and optimize the flow rate of upcoming production test.

Fujii, T.; Noguchi, S.; Takayama, T.; Suzuki, K.; Yamamoto, K.

2012-12-01

240

Using open hole and cased-hole resistivity logs to monitor gas hydrate dissociation during a thermal test in the mallik 5L-38 research well, Mackenzie Delta, Canada  

USGS Publications Warehouse

Gas hydrates, which are naturally occurring ice-like combinations of gas and water, have the potential to provide vast amounts of natural gas from the world's oceans and polar regions. However, producing gas economically from hydrates entails major technical challenges. Proposed recovery methods such as dissociating or melting gas hydrates by heating or depressurization are currently being tested. One such test was conducted in northern Canada by the partners in the Mallik 2002 Gas Hydrate Production Research Well Program. This paper describes how resistivity logs were used to determine the size of the annular region of gas hydrate dissociation that occurred around the wellbore during the thermal test in the Mallik 5L-38 well. An open-hole logging suite, run prior to the thermal test, included array induction, array laterolog, nuclear magnetic resonance and 1.1-GHz electromagnetic propagation logs. The reservoir saturation tool was run both before and after the thermal test to monitor formation changes. A cased-hole formation resistivity log was run after the test.Baseline resistivity values in each formation layer (Rt) were established from the deep laterolog data. The resistivity in the region of gas hydrate dissociation near the wellbore (Rxo) was determined from electromagnetic propagation and reservoir saturation tool measurements. The radius of hydrate dissociation as a function of depth was then determined by means of iterative forward modeling of cased-hole formation resistivity tool response. The solution was obtained by varying the modeled dissociation radius until the modeled log overlaid the field log. Pretest gas hydrate production computer simulations had predicted that dissociation would take place at a uniform radius over the 13-ft test interval. However, the post-test resistivity modeling showed that this was not the case. The resistivity-derived dissociation radius was greatest near the outlet of the pipe that circulated hot water in the wellbore, where the highest temperatures were recorded. The radius was smallest near the center of the test interval, where a conglomerate section with low values of porosity and permeability inhibited dissociation. The free gas volume calculated from the resistivity-derived dissociation radii yielded a value within 20 per cent of surface gauge measurements. These results show that the inversion of resistivity measurements holds promise for use in future gas hydrate monitoring. ?? 2008 Society of Petrophysicists and Well Log Analysts. All rights reserved.

Anderson, B. I.; Collett, T. S.; Lewis, R. E.; Dubourg, I.

2008-01-01

241

Log Algebra  

NSDL National Science Digital Library

In this activity, students solve exponential equations where the unknown is contained in the exponent. Students learn that taking base-10 or base-2 logs pulls down the exponent, allowing the unknown to be isolated and solved.  This activity is activity C3 in the "Far Out Math" educator's guide. Lessons in the guide include activities in which students measure, compare quantities as orders of magnitude, become familiar with scientific notation, and develop an understanding of exponents and logarithms using examples from NASA's GLAST mission. These are skills needed to understand the very large and very small quantities characteristic of astronomical observations. Note: In 2008, GLAST was renamed Fermi, for the physicist Enrico Fermi.

242

INTEGRATED APPROACH FOR THE PETROPHYSICAL INTERPRETATION OF POST-AND PRE-STACK 3-D SEISMIC DATA, WELL-LOG DATA, CORE DATA, GEOLOGICAL INFORMATION AND RESERVOIR PRODUCTION DATA VIA BAYESIAN STOCHASTIC INVERSION  

SciTech Connect

The present report summarizes the work carried out between September 30, 2000 and September 30, 2004 under DOE research contract No. DE-FC26-00BC15305. During the three-year project period, we carried out extensive studies on the inversion post-stack and pre-stack data together with well logs, petrophysical information and fluid flow data. We have achieved all the project goals including development of algorithm for joint inversion of pre-stack seismic data, well logs, and time records of fluid production measurements using stochastic inversion algorithms which were demonstrated on realistic synthetic and field data. Our accomplishments are: (1) Joint inversion of post-stack seismic, well log, fluid flow, and petrophysical data: we demonstrated the technique with application to data from the Gulf of Mexico. (2) Development of a robust pre-stack full waveform inversion algorithm: A new approach based on iteration-adaptive regularization that makes use of plane wave transformed seismic data, was developed and applied to OBC dataset from the Gulf of Thailand. The algorithm was also implemented on a cluster of personal computers. (3) Joint inversion of pre-stack seismic and well-log data: A new stochastic optimization algorithm that makes use of the essential features of seismic and well log data was developed and tested on realistic synthetic dataset. (4) Joint inversion of pre-stack seismic and fluid flow data: A novel technique was developed to optimally combine seismic and flow data. The technique makes very realistic estimate of porosity; sensitivity of the flow parameters to two disparate datasets was studied extensively. (5) Direct estimation of petrophysical parameters from seismic data: The pre-stack waveform inversion was modified to invert directly for porosity and saturation using the Biot-Gassmann equation at each iteration step. The final report contains abridged versions of some of our inventions. The works resulted in several peer-reviewed publications. Five papers have been communicated for peer-reviewed publication, and seven papers were presented at conferences. All of these publications and presentations stemmed from work directly related to the goals of our DOE project.

Carlos Torres-Verdin; Mrinal K. Sen

2004-09-01

243

New Probe for gamma Spectrometric Logging.  

National Technical Information Service (NTIS)

The new spectrometric probe contains an analog to digital converter (ADG). The advantage of this device are as follows. All the winches used for logging are equipped with cables containing electrical conductors. In consequence the attenuation of the cable...

P. Dumesnil

1983-01-01

244

Relation between the fractal distribution of elastic parameters in the earth crust and the Gutenberg-Richter b-value of earthquakes: A method to estimate b-values from sonic well logs  

NASA Astrophysics Data System (ADS)

Sonic well logs provide in situ measurements of physical properties and their fluctuations in the earth crust. The analysis of log data from various sites suggests that elastic parameters exhibit a heterogeneous distribution characterized by broad band fractal scaling. However, the significance of this finding for the distribution of stress inside the earth crust has not yet been analyzed. Independently from the works above, it was shown that power law scaling of the number of earthquake with magnitude, expressed in the Gutenberg-Richter relation, can be explained by fractal distributed stress. However, a direct reason for the fractal distribution of stress is still lacking. In this paper we establish relations between the fractal distribution of elastic parameters, stress field variations and the Gutenberg-Richter b-value of earthquakes. We extract information about elastic parameter distribution from sonic logs to create an elastically heterogeneous 3D random medium with a fractal spatial correlation function. Using the finite element program Abaqus we apply an externally homogeneous stress field and compute the resulting stress distribution inside the elastically heterogeneous medium. We use geomechanical considerations to determine the distribution of Coulomb Failure Stress (CFS) as a measure of the vicinity to failure. The resulting CFS distribution is highly heterogeneous, of fractal nature and strongly related to the initially assigned elastic parameters. We assume that rupturing, once it is initiated (e.g. by an increase of stress or pore pressure), takes place along isovolumes of CFS. We determine the number size distribution of isovolumes and compute their characteristic area. The distribution of characteristic fault planes and correspondingly magnitudes exhibits power law scaling according to the Gutenberg Richter law. We find that elastic heterogeneity leads to b-values in the range of 1well logs. The application of our method to well log data measured along the Continental Deep Drilling Site (KTB, Germany) main hole results in a realistic b-value of b=1.4.

Langenbruch, C.; Shapiro, S. A.

2012-12-01

245

Estimation of Performance of an Active Well Coincidence Counter Equipped with Boron-Coated Straw Neutron Detectors - 13401  

SciTech Connect

He-3, a very rare isotope of natural helium gas, has ideal properties for the detection of thermal neutrons. As such it has become the standard material for neutron detectors and sees ubiquitous use within many radiometric applications that require neutron sensitivity. Until recently, there has been a fairly abundant supply of He-3. However, with the reduction in nuclear weapons, production of tritium ceased decades ago and the stockpile has largely decayed away, reducing the available He-3 supply to a small fraction of that needed for neutron detection. A suitable and rapidly-deployable replacement technology for neutron detectors must be found. Many potential replacement technologies are under active investigation and development. One broad class of technologies utilizes B-10 as a neutron capture medium in coatings on the internal surfaces of proportional detectors. A particular implementation of this sort of technology is the boron-coated 'straw' (BCS) detectors under development by Proportional Technologies, Inc. (PTi). This technology employs a coating of B-10 enriched boron carbide (B{sub 4}C) on the inside of narrow tubes, roughly 4 mm in diameter. A neutron counter (e.g. a slab, a well counter, or a large assay counter designed to accommodate 200 liter drums) could be constructed by distributing these narrow tubes throughout the polyethylene body of the counter. One type of neutron counter that is of particular importance to safeguards applications is the Active Well Coincidence Counter (AWCC), which is a Los Alamos design that traditionally employs 42 He-3 detectors. This is a very flexible design which can accurately assay small samples of uranium- and plutonium-bearing materials. Utilizing the MCNPX code and benchmarking against measurements where possible, the standard AWCC has been redesigned to utilize the BCS technology. Particular aspects of the counter performance include the single-neutron ('singles') detection efficiency and the time constant for the decrease in neutron population in the counter following a fission event (a.k.a. the die-away time). Results of the modeling and optimization are presented. (authors)

Young, B.M. [Canberra Industries, Inc., 800 Research Parkway, Meriden, CT 06450 (United States)] [Canberra Industries, Inc., 800 Research Parkway, Meriden, CT 06450 (United States); Lacy, J.L.; Athanasiades, A. [Proportional Technologies, Inc., 8022 El Rio Street, Houston, TX 77054 (United States)] [Proportional Technologies, Inc., 8022 El Rio Street, Houston, TX 77054 (United States)

2013-07-01

246

Interpretation of geophysical logs, aquifer tests, and water levels in wells in and near the North Penn Area 7 Superfund site, Upper Gwynedd Township, Montgomery County, Pennsylvania, 2000-02  

USGS Publications Warehouse

Ground water in the vicinity of various industrial facilities in Upper Gwynedd Township and Lansdale Borough, Montgomery County, Pa., is contaminated with various volatile organic compounds (VOCs). The 2-square-mile area was placed on the National Priorities List as the North Penn Area 7 Superfund site by the U.S. Environmental Protection Agency (USEPA) in 1989. The U.S. Geological Survey (USGS) conducted geophysical logging, aquifer testing, water-level monitoring, and streamflow measurements in the vicinity of North Penn Area 7 beginning autumn 2000 to assist the USEPA in developing an understanding of the hydrogeologic framework in the area as part of the USEPA Remedial Investigation. The study area is underlain by Triassic and Jurassic-age sandstones, siltstones, and shales of the Lockatong Formation and the Brunswick Group. Regionally, these rocks strike northeast and dip to the northwest. The sequence of rocks form a fractured-sedimentary-rock aquifer that acts as a set of confined to partially confined layered aquifers of differing permeabilities. The aquifers are recharged by precipitation and discharge to streams and wells. The Wissahickon Creek headwaters are less than 1 mile northeast of the study area, and this stream flows southwest to bisect North Penn Area 7. Ground water is pumped in the vicinity of North Penn Area 7 for industrial use and public supply. The USGS collected geophysical logs for 16 wells that ranged in depth from 50 to 623 feet. Aquifer-interval-isolation testing was done in 9 of the 16 wells, for a total of 30 zones tested. A multiple-well aquifer test was conducted by monitoring the response of 14 wells to pumping a 600-ft deep production well in February and March 2002. In addition, water levels were monitored continuously in three wells in the area and streamflow was measured quarterly at two sites on Wissahickon Creek from December 2000 through September 2002. Geophysical logging identified water-bearing zones associated with high-angle fractures and bedding-plane openings throughout the depth of the boreholes. Heatpulse-flowmeter measurements under nonpumping, ambient conditions indicated that borehole flow, where detected, was in the upward direction in three of the eight wells and in the downward direction in three wells. In two wells, both upward and downward flow were measured. Heatpulse-flowmeter measurements under pumping conditions were used to identify the most productive intervals in wells. Correlation of natural-gamma-ray and single-point-resistance logs indicated that bedding in the area probably strikes about 40 degrees northeast and dips from 6 to 7 degrees northwest. Aquifer intervals isolated by inflatable packers in wells were pumped to test productivity and to collect samples to determine chemical quality of water produced from the interval. Interval-isolation testing confirmed the presence of vertical hydraulic gradients indicated by heatpulse-flowmeter measurements. The specific capacities of isolated intervals ranged over two orders of magnitude, from 0.02 to more than 3.6 gallons per minute per foot. Intervals adjacent to isolated pumped intervals showed little response to pumping the isolated zone. The presence of vertical hydraulic gradients and lack of adjacent-interval response to pumping in isolated intervals indicate a limited degree of vertical hydraulic connection between the aquifer intervals tested. Concentrations of most VOC contaminants generally were highest in well-water samples from the shallowest isolated intervals, with some exceptions. Trichloroethylene, cis-1,2-dichloroethylene, and toluene were the most frequently detected VOCs, with maximum concentrations of greater than 340, 680, and greater than 590 micrograms per liter, respectively. Results of the aquifer test with multiple observation wells showed that water levels in 4 of the 14 wells declined in response to pumping. The four wells that responded to pumping are either along str

Senior, Lisa A.; Cinotto, Peter J.; Conger, Randall W.; Bird, Philip H.; Pracht, Karl A.

2005-01-01

247

Acoustic cement bond logging diagnostics for geothermal applications  

SciTech Connect

For the successful and safe operation of a geothermal well, casing and cement conditions must be accurately determined. Cement bond logs are needed to detect channels or water pockets in the cement between the pipe and the formation and to determine the condition of the cement bond to the pipe and to the formation. Instrumentation for making such measurements is limited by the temperature capabilities (< 175/sup 0/C) of existing logging equipment which was developed for the oil and gas industry. This paper reviews an acoustic system of the type that is needed for geothermal cementing inspection, identifies the principle deficiencies in its high temperature use, and describes Sandia's R and D project for developing high temperature acoustic cement bond logging diagnostics.

Chang, H.T.

1981-01-01

248

GEOPHYSICAL WELL LOG/CORE DESCRIPTIONS, CHEROKEE AND BUG FIELDS, SAN JUAN COUNTY, UTAH, AND LITTLE UTE AND SLEEPING UTE FIELDS, MONTEZUMA COUNTY, COLORADO  

SciTech Connect

Over 400 million barrels (64 million m{sup 3}) of oil have been produced from the shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation in the Paradox Basin, Utah and Colorado. With the exception of the giant Greater Aneth field, the other 100 plus oil fields in the basin typically contain 2 to 10 million barrels (0.3-1.6 million m{sup 3}) of original oil in place. Most of these fields are characterized by high initial production rates followed by a very short productive life (primary), and hence premature abandonment. Only 15 to 25 percent of the original oil in place is recoverable during primary production from conventional vertical wells. An extensive and successful horizontal drilling program has been conducted in the giant Greater Aneth field. However, to date, only two horizontal wells have been drilled in small Ismay and Desert Creek fields. The results from these wells were disappointing due to poor understanding of the carbonate facies and diagenetic fabrics that create reservoir heterogeneity. These small fields, and similar fields in the basin, are at high risk of premature abandonment. At least 200 million barrels (31.8 million m{sup 3}) of oil will be left behind in these small fields because current development practices leave compartments of the heterogeneous reservoirs undrained. Through proper geological evaluation of the reservoirs, production may be increased by 20 to 50 percent through the drilling of low-cost single or multilateral horizontal legs from existing vertical development wells. In addition, horizontal drilling from existing wells minimizes surface disturbances and costs for field development, particularly in the environmentally sensitive areas of southeastern Utah and southwestern Colorado.

Thomas C. Chidsey Jr; David E. Eby; Laura L. Wray

2003-12-01

249

Avo Analysis of Gas Hydrates At Hydrate Ridge Off The Cascadia Margin Using Well-log Calibrated Ocean Bottom Seismometer (obs) Data  

Microsoft Academic Search

Hydrate Ridge, off the Oregon continental margin, was the focus of a detailed seis- mic study investigating gas hydrates during cruise SO150 aboard the R\\/V Sonne in September 2000. Wide-angle OBS measurements as well as surface and deep tow streamer data were collected using five different seismic sources. A broad frequency range (5-500 Hz) for analysing the Bottom Simulating Reflector

J. Petersen; C. Papenberg; D. Klaeschen

2002-01-01

250

Digital archive of drilling mud weight pressures and wellbore temperatures from 49 regional cross sections of 967 well logs in Louisiana and Texas, onshore Gulf of Mexico basin  

USGS Publications Warehouse

This document provides the digital archive of in-situ temperature and drilling mud weight pressure data that were compiled from several historical sources. The data coverage includes the states of Texas and Louisiana in the Gulf of Mexico basin. Data are also provided graphically, for both Texas and Louisiana, as plots of temperature as a function of depth and pressure as a function of depth. The minimum, arithmetic average, and maximum values are tabulated for each 1,000-foot depth increment for temperature as well as pressure in the Texas and Louisiana data.

Burke, Lauri A.; Kinney, Scott A.; Kola-Kehinde, Temidayo B.

2011-01-01

251

Log Truck-Weighing System  

NASA Technical Reports Server (NTRS)

ELDEC Corp., Lynwood, Wash., built a weight-recording system for logging trucks based on electronic technology the company acquired as a subcontractor on space programs such as Apollo and the Saturn launch vehicle. ELDEC employed its space-derived expertise to develop a computerized weight-and-balance system for Lockheed's TriStar jetliner. ELDEC then adapted the airliner system to a similar product for logging trucks. Electronic equipment computes tractor weight, trailer weight and overall gross weight, and this information is presented to the driver by an instrument in the cab. The system costs $2,000 but it pays for itself in a single year. It allows operators to use a truck's hauling capacity more efficiently since the load can be maximized without exceeding legal weight limits for highway travel. Approximately 2,000 logging trucks now use the system.

1977-01-01

252

Formation productivity evaluation from temperature logs  

Microsoft Academic Search

After a brief review of the use of temperature logs for measuring the volume of gas flow in a borehole, this paper deals with the application of temperature logs to evaluate the mechanism of gas production. A method for evaluation of the formation productivity is introduced, making use of a temperature log of the flowing gas well, the reservoir temperature

J. M. Bird; N. Frost

1965-01-01

253

Integrated Analysis of Flow, Temperature, and Specific-Conductance Logs and Depth-Dependent Water-Quality Samples from Three Deep Wells in a Fractured-Sandstone Aquifer, Ventura County, California  

USGS Publications Warehouse

Analysis of flow, temperature, and specific-conductance logs and depth-dependent water-quality samples collected under ambient and pumped conditions provided a preliminary delineation of flow zones and water quality in three deep abandoned water-supply wells. The integrated analysis was completed as part of the characterization of a fractured-sandstone aquifer in the mountainous setting of the Santa Susana Field Laboratory in southern Ventura County, California. In the deepest well, which was 1,768 feet deep and had the highest specific capacity (120 gallons per minute per foot), flow zones were detected at 380 feet (base of casing) and at 440, 595, and 770 feet in the open hole. Under ambient conditions, measured flow was downward from the 380- and 440-foot zones to the 595- and 770-foot zones. Under pumped conditions, most of flow was contributed by the 595-foot zone. Flow from the 380- and 440-foot zones appeared to have lower specific conductance and higher trichloroethylene concentrations than that from the 595-foot zone. In the shallowest well, which was reportedly 940 feet deep but only logged to 915 feet due to blockage, flow zones were detected behind the perforated casing and at 867 feet in the open hole. Under ambient conditions, downward and upward flows appeared to exit at a zone behind the perforated casing at 708 feet. Most of the pumped flow was contributed from zones behind the perforated casing between 565 and 708 feet. Pumped flow also was contributed by zones at 867 feet and below the logged depth. Volatile organic compounds were not detected in the ambient and pumped flows. In the third well, which was 1,272 feet deep and had the lowest specific capacity (3.6 gallons per minute per foot), flow zones were detected in the open hole above and just below the water level near 337 feet and at 615, 785, 995, and 1,070 feet. Under ambient conditions, measured flow in well was downward from the shallowmost zones to the 995-foot zone. Fracture zones at 615, 785, and 995 feet each contributed about one-third of the pumped flow measured below the pump. Volatile organic compounds were not detected in the ambient and pumped flows.

Williams, John H.; Knutson, Kevin D.

2009-01-01

254

The Meaning of Logs  

Microsoft Academic Search

While logging events is becoming increasingly common in computing, in communication and in collaborative work, log systems need to satisfy increasingly challenging (if not conflicting) requirements. Despite the growing pervasiveness of log systems, to date there is no high-level framework which allows one to model a log system and to check whether it meets the requirements it should satisfy. In

Sandro Etalle; Fabio Massacci; Artsiom Yautsiukhin

2007-01-01

255

Impeller flow-meter logging of vertical cross flow between basalt aquifers through wells at the Idaho National Engineering Laboratory, Eastern Snake River Plain, Idaho. Progress report, June 22, 1992  

SciTech Connect

An impeller flowmeter was used with a COLOG digital acquisition system to determine existing borehole flows, to compare with previous logging results, and to acquire flow measurements of vertical cross-flow of water in the wells between permeable zones in the open-hole intervals. The direction of flow found was predominantly downward with velocities ranging from 0-30 ft/min. Some flow reversals were noted and attributed to nearby pumping wells. USGS wells 44 and 46 were studied in September, 1991 near the Idaho Chemical Processing Plant (ICPP). The results showed a usual overall flow direction downward with flow entering the wells at around 510 to 600 ft. below the land surface. Water exited these wells at lower levels around 550 to 580 ft. Flow velocities ranged up to 24 ft/min. Using published aquifer parameters, the rate of propagation of a pressure change in an aquifer was calculated for the well CPP-2 turning on and off, at 3100 gpm.

Bennecke, W.M.; Wood, S.H.

1992-12-31

256

Well log evaluation of natural gas hydrates.  

National Technical Information Service (NTIS)

Gas hydrates are crystalline substances composed of water and gas, in which a solid-water-lattice accommodates gas molecules in a cage-like structure. Gas hydrates are globally widespread in permafrost regions and beneath the sea in sediment of outer cont...

T. S. Collett

1992-01-01

257

Preliminary interpretation of geophysical logs and in situ hydrologic properties in fractured limestone at Loring Air Force Base  

Microsoft Academic Search

Recent hydrogeologic investigations at Loring Air Force Base (AFB) in Limestone, Maine, showed that subsurface data provided by borehole geophysical logging and subsequently installed custom-designed multilevel monitoring wells greatly complement each other in understanding contaminant migration pathways in bedrock. Based on interpretations of borehole geophysical suites, four wells drilled into undifferentiated limestone were equipped with Westbay packer\\/port units. Individual hydraulic

L. L. Dearborn; P. S. Baker; J. B. Davis

1989-01-01

258

Frac packs complicate PNC log evaluation  

SciTech Connect

Borate-crosslinked fluids and/or ceramic proppants commonly included in frac-pack well completions can compliance pulsed neutron capture (PNC) log evaluation. PNC logs are routinely run in cased holes. Two common applications include identifying formation fluid and calculating the percent water saturation in the rock pore spaces near the well bore. The paper discusses PNC logs, a case history of a West Delta oil well, laboratory work, and results. Recommendations are given.

Bean, C.L.; Ali, S.A. [Chevron U.S.A. Production Co., New Orleans, LA (United States); Salaita, G.N. [Chevron Petroleum Technology Co., Houston, TX (United States)

1996-12-23

259

Considerations Related to Drilling Methods in Planning and Performing Borehole-Geophysical Logging for Ground-Water Studies.  

National Technical Information Service (NTIS)

The report reviews various aspects of drilling, sampling and borehole geophysical logging that affect the effectiveness of well-log interpretation and the precision of well-log calibration using recovered samples, cuttings, or driller's logs. Because well...

R. E. Hodges, W. E. Teasdale

1991-01-01

260

Petrographic image logging system  

Microsoft Academic Search

The Petrographic Image Logging System (PILS) is a logging system data base for Macintosh computers that allows the merging of traditional wire-line, core, and mud log data with petrographic images. The system is flexible; it allows the user to record, manipulate, and display almost any type of character, graphic, and image information. Character and graphic data are linked and entry

C. J. Payne; M. R. Ulrich; G. B. Maxwell; J. P. Adams

1991-01-01

261

Log N-log S in inconclusive  

NASA Technical Reports Server (NTRS)

The log N-log S data acquired by the Pioneer Venus Orbiter Gamma Burst Detector (PVO) are presented and compared to similar data from the Soviet KONUS experiment. Although the PVO data are consistent with and suggestive of a -3/2 power law distribution, the results are not adequate at this state of observations to differentiate between a -3/2 and a -1 power law slope.

Klebesadel, R. W.; Fenimore, E. E.; Laros, J.

1983-01-01

262

Horizontal wells  

SciTech Connect

This paper covers all aspects of horizontal well technology including geology, well performance and productivity, well logging, naturally fractured reservoirs, and well test analysis. Each topic is discussed in terms of the newest tools available, with emphasis given to preplanning and communication between all levels of personnel. Case histories from sites around the world are highlighted.

Aguilera, R.A.; Cordell, G.M.; Nicholl, G.W.; Artindale, J.S.; Ng, M.C.; Runions, G.A.

1991-01-01

263

LogScope  

NASA Technical Reports Server (NTRS)

LogScope is a software package for analyzing log files. The intended use is for offline post-processing of such logs, after the execution of the system under test. LogScope can, however, in principle, also be used to monitor systems online during their execution. Logs are checked against requirements formulated as monitors expressed in a rule-based specification language. This language has similarities to a state machine language, but is more expressive, for example, in its handling of data parameters. The specification language is user friendly, simple, and yet expressive enough for many practical scenarios. The LogScope software was initially developed to specifically assist in testing JPL s Mars Science Laboratory (MSL) flight software, but it is very generic in nature and can be applied to any application that produces some form of logging information (which almost any software does).

Havelund, Klaus; Smith, Margaret H.; Barringer, Howard; Groce, Alex

2012-01-01

264

Data logging for technical services at CERN  

Microsoft Academic Search

A data-logging system for the technical infrastructure of CERN was developed and has been used for over two years by the Technical Control Room (TCR) and by equipment groups. Hardware and some software are common to the SPS\\/LEP accelerator control system, though some particular features had to be implemented to meet specific requirements of the TCR. One of these requirements

R. Martini; H. Laeger; P. Ninin; E. Pfirsch; P. Sollander

1995-01-01

265

Three-dimensional structure of the greater Los Angeles basin: Insights from transects and models that integrate industry seismic reflection profiles, well logs, surface geology, and relocated earthquake catalogs  

NASA Astrophysics Data System (ADS)

We describe the geometry and activity of major, seismogenic fault systems in the Los Angeles basin and adjacent offshore areas using regional seismic reflection transects and three-dimensional structural and velocity models. The seismic transects, which integrates relocated earthquakes, focal mechanisms, and well control, image several active fault systems (Palos Verdes, Newport-Inglewood, Compton, Las Cienegas, Elysian Park, Puente Hills, Whittier, Oceanside, etc.) that threaten the Los Angeles metropolitan region. The models describe the three dimensional geometry and kinematic interaction of these faults systems, and incorporate 35,000 km of industry seismic reflection data, more than 1,000 well logs, surface geology, and re-located earthquake catalogs. The Los Angeles basin lies at the juncture of the Transverse and Peninsular Ranges, and thus contains fault systems that belong to both of these tectonic provinces. The southern basin and Inner California Borderlands are dominated by northwest-southeast trending strike-slip and blind-thrust systems, parallel to the grain of the Peninsular Ranges, that partition oblique convergence. Many of these structures are reactivated normal faults that formed during Neogene rifting of the southern California margin. In contrast, the northern Los Angeles basin is dominated by east-west trending thrust and strike-slip systems that accommodate north-south shortening. These faults are part of the Transverse Ranges province, and locally dissect older Peninsular Range trends that are carried northward by motion along the San Andreas and related strike-slip fault systems. We consider the implications of these tectonic models for regional earthquake hazards assessment.

Shaw, J. H.; Plesch, A.; Suess, M. P.; Rivero, C. A.

2001-12-01

266

Ulysses log 1992  

NASA Technical Reports Server (NTRS)

The Ulysses Log tells the story of some intriguing problems that we (=The Spacecraft Team) have encountered. Ulysses was launched on 6 Oct. 1990, and it made the fastest trip to Jupiter (8 Feb. 1992). It is presently going out of the ecliptic. This paper presents log entries from the following areas: (1) ingenious maneuvers; (2) telecommunication problems; and (3) surprises.

Perez, Raul Garcia

1993-01-01

267

Formation Productivity Evaluation From Temperature Logs  

Microsoft Academic Search

A brief review is presented of the methods of quantitative evaluation of borehole temperature logs as applied to gas flow measurements. A method for evaluation of the formation productivity is introduced, making use of a temperature log of the flowing gas well, the reservoir temperature and pressure, and the Joule-Thomson expansion temperature of the gas. A method is discussed for

J. M. Bird; N. Frost

1966-01-01

268

Methods of generating synthetic acoustic logs from resistivity logs for gas-hydrate-bearing sediments  

USGS Publications Warehouse

Methods of predicting acoustic logs from resistivity logs for hydrate-bearing sediments are presented. Modified time average equations derived from the weighted equation provide a means of relating the velocity of the sediment to the resistivity of the sediment. These methods can be used to transform resistivity logs into acoustic logs with or without using the gas hydrate concentration in the pore space. All the parameters except the unconsolidation constants, necessary for the prediction of acoustic log from resistivity log, can be estimated from a cross plot of resistivity versus porosity values. Unconsolidation constants in equations may be assumed without rendering significant errors in the prediction. These methods were applied to the acoustic and resistivity logs acquired at the Mallik 2L-38 gas hydrate research well drilled at the Mackenzie Delta, northern Canada. The results indicate that the proposed method is simple and accurate.

Lee, Myung W.

1999-01-01

269

Field geologist's training guide: An introduction to oilfield geology, mud logging and formation evaluation  

SciTech Connect

This handbook presents a basic overview of and introduction to petroleum geology, oilfield terminolgy and formation evaluation procedures. The chapters introduce many key concepts. Petroleum geology, oilfield fluids, rig types and their components, wellsite equipment and the environment in which field geologists work are presented in detail. Drilling and completing a well and formation evaluation procedures are examined from the logging geologist's perspective. The appendices contain a wide range of information such as general abbreviations, glossary, and bit classification.

Whittaker, A.

1985-01-01

270

INTEGRATED APPROACH FOR THE PETROPHYSICAL INTERPRETATION OF POST- AND PRE-STACK 3-D SEISMIC DATA, WELL-LOG DATA, CORE DATA, GEOLOGICAL INFORMATION AND RESERVOIR PRODUCTION DATA VIA BAYESIAN STOCHASTIC INVERSION  

SciTech Connect

The present report summarizes the work carried out between September 30, 2002 and August 30, 2003 under DOE research contract No. DE-FC26-00BC15305. During the third year of work for this project we focused primarily on improving the efficiency of inversion algorithms and on developing algorithms for direct estimation of petrophysical parameters. The full waveform inversion algorithm for elastic property estimation was tested rigorously on a personal computer cluster. For sixteen nodes on the cluster the parallel algorithm was found to be scalable with a near linear speedup. This enabled us to invert a 2D seismic line in less than five hours of CPU time. We were invited to write a paper on our results that was subsequently accepted for publication. We also carried out a rigorous study to examine the sensitivity and resolution of seismic data to petrophysical parameters. In other words, we developed a full waveform inversion algorithm that estimates petrophysical parameters such as porosity and saturation from pre-stack seismic waveform data. First we used a modified Biot-Gassmann equation to relate petrophysical parameters to elastic parameters. The transformation was validated with a suite of well logs acquired in the deepwater Gulf of Mexico. As a part of this study, we carried out a sensitivity analysis and found that the porosity is very well resolved while the fluid saturation remains insensitive to seismic wave amplitudes. Finally we conducted a joint inversion of pre-stack seismic waveform and production history data. To overcome the computational difficulties we used a simpler waveform modeling algorithm together with an efficient subspace approach. The algorithm was tested on a realistic synthetic data set. We observed that the use of pre-stack seismic data helps tremendously to improve horizontal resolution of porosity maps. Finally, we submitted four publications to refereed technical journals, two refereed extended abstracts to technical conferences, and delivered two oral presentation at a technical forum. All of these publications and presentations stemmed from work directly related to the goals of our DOE project.

Carlos Torres-Verdin; Mrinal K. Sen

2004-03-01

271

Horizontal wells  

SciTech Connect

This book covers all the aspects of horizontal wells, from geology and reservoir characteristics to the complex math and physics needed for well logging and well test analysis. Drilling, completions, and well performance and productivity are discussed thoroughly. Economic considerations are integrated with practical methodology to render the book as useful as possible. An exceptionally detailed treatment of thermal recovery for heavy oils rounds out the comprehensive approach. Numerical simulations, worked examples, and case histories are included.

Aquilera, R.; Artindale, J.S.; Cordell, G.M.; Ng, M.C.; Nicholl, G.W.; Runions, G.A.

1991-01-01

272

Acoustic paramagnetic logging tool  

DOEpatents

New methods and apparatus are disclosed which allow measurement of the presence of oil and water in geological formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleons present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth3 s magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation . The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be preformed in open boreholes and in cased well bores.

Vail, III, William B. (Bothell, WA)

1988-01-01

273

6. Log calving barn. Interior view showing log postandbeam support ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. Log calving barn. Interior view showing log post-and-beam support system and animal stalls. - William & Lucina Bowe Ranch, Log Calving Barn, 230 feet south-southwest of House, Melrose, Silver Bow County, MT

274

Interactive Reflective Logs  

NSDL National Science Digital Library

The authors created an interactive reflective log (IRL) to provide teachers with an opportunity to use a journal approach to record, evaluate, and communicate student understanding of science concepts. Unlike a traditional journal, the IRL incorporates pr

Deaton, Benjamin E.; Deaton, Cynthia M.; Leland, Katina

2010-11-01

275

A lithological segmentation from sonic logs using wavelet transform  

NASA Astrophysics Data System (ADS)

The analysis of well logs allows to extract worthy information about the sub-surface. Here, the logs are used to perform a lithological segmentation using the wavelet transform. The basic idea consists of estimating the local regularity strength, measured by the Hölder exponent (H), using the wavelet transform. The change in the H value allows to identify the lithological discontinuities within the strata crossed by the well. This method is first implemented on synthetic logs, then applied to real sonic logs data recorded in Algerian boreholes. The results reveal that efficiency of the proposed technique in the lithological segmentation. Keywords: well log, wavelet transform, Hölder exponent, regularity

Gaci, S.; Zaourar, N.; Ouadfeul, S.

2012-04-01

276

4. Log chicken house (far left foreground), log bunkhouse (far ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. Log chicken house (far left foreground), log bunkhouse (far left background), one-room log cabin (left of center background), log root cellar (center), post-and-beam center in foreground, and blacksmith shop (far right foreground). View to southeast. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

277

Questa Baseline and Pre-Mining Ground-Water Quality Investigation 15.-Methods of Phase II and III Well Installation and Development and Results of Well Logging, Hydraulic Testing, and Water-Level Measurements in the Red River Valley, New Mexico, 2002-04  

USGS Publications Warehouse

In April 2001, the U.S. Geological Survey and the New Mexico Environment Department began a cooperative study to infer the pre-mining ground-water chemistry at the Molycorp molybdenum mine site in the Red River Valley of north- central New Mexico. This report is one in a series of reports that can be used to determine pre-mining ground-water conditions at the mine site. Weathering of hydrothermally altered bedrock in the study area has resulted in steep, highly erosive, and sparsely vegetated scar areas that are clearly visible from the ground and in aerial photographs. Runoff from intense summer rainfall over tributary drainages containing scar areas can transport large quantities of sediment and form debris fans where these tributaries join the Red River. Twenty-nine observation wells were installed in three phases as part of this study in the Red River Valley and tributary drainages. Eight Phase II observation wells were drilled using an air-rotary/hammer rig. Three Phase II and 10 phase III small-diameter wells were installed using a direct-push rig. Lithologic logs were recorded for all eight Phase II drilled wells. Borehole geophysical logging (including natural gamma, induction, and single-detector neutron) was conducted in three Phase II wells. Aquifer tests conducted during 2003 to estimate the hydraulic properties of debris-flow and Red River alluvial deposits in and near Straight Creek included a flow-meter survey, slug tests, and a pumping test. Results of a flow-meter survey in well SC-7A indicated that about 77 percent of the water entered the well from a 10-foot-thick zone near the top of the screened interval and about 23 percent of the water entered the well from a 15-foot-thick zone near the bottom of the screened interval. Slug tests, performed in 11 wells during June 3-5, 2003, indicated that the mean and median estimated hydraulic conductivities for debris-flow deposits were 15.25 and 15.35 feet per day, respectively, for bedrock were 0.12 and 0.08 feet per day, respectively, and for mixed debris flow and Red River alluvium were 73-207 (estimated range) and 80 feet per day. In general, bedrock has the smallest hydraulic conductivity, debris-flow material has the next highest hydraulic conductivity, and mixed debris flow and Red River alluvium has the largest hydraulic conductivity. A pumping test conducted December 3-4, 2003, using well AWWT-1 as the pumped well, and wells AWWT-2, SC-5A, SC-5B, SC-7A, and SC-8A as observation wells, indicated estimated transmissivity of 12,000 to 34,000 feet squared per day and estimated hydraulic conductivity of 230 to 340 feet per day. Water-level measurements in wells SC-6A, SC-7A, SC-8A, and the Hottentot, Hansen, and La Bobita wells show that water levels typically rose rapidly during melting of the winter snowpack in the springtime and then generally declined during the rest of the year. The water-level rise in response to spring snowmelt occurred earlier and was smaller at larger distances from the Red River. Differences between the stage in the Red River and water levels in wells SC-8A and SC-9A, and the absence of water in well SC-9A at the time of well completion, indicate that the Red River has a poor hydraulic connection to the underlying ground-water system and the surface-water system is perched above the ground-water system at this site. Water levels in Phase III wells indicate that the Red River and the shallow ground-water system are connected hydraulically from near wells 4-1D and 4-1S downstream to near wells 2-1 and 2-2 but are poorly connected near the La Bobita well and well 1.

Blanchard, Paul J.; Bartolino, James R.; Donohoe, Lisa C.; McAda, Douglas P.; Naus, Cheryl A.; Morin, Roger H.

2007-01-01

278

A Highly Available Log Service for Transaction Termination  

Microsoft Academic Search

Distributed transaction processing hinges on enforcing agreement among the involved resource managers on whether to commit or abort transactions (atomicity) and on making their updates permanent (durability). This paper introduces a log service which abstracts these tasks. The service logs commit and abort votes as well as the updates performed by each resource manager. Based on the votes, the log

Lásaro J. Camargos; Marcin Wieloch; Fernando Pedone; Edmundo Roberto Mauro Madeira

2008-01-01

279

Gamma ray spectral logging: A new evaluation frontier  

SciTech Connect

In the evaluation of clastic reservoirs, even the slightest amount of accessory minerals present in an otherwise clean formation can distort the readings from conventional well logs. In this case, natural gamma ray spectral logging has proven a useful aid. This article addresses the use of the spectral log in glauconitic sand, chert arenites, granite washes and micaceous sandstones.

Fertl, W.H.

1983-08-01

280

Evaluating and logging tight rocks of south Texas  

Microsoft Academic Search

Drilling and production experience in the tight-rock oil- and gas-producing sands in south Texas have taught operators the importance of comprehensive logging programs for evaluating the formations, notes Schlumberger Well Services. Sample logs from throughout the play show that porosity and shaliness are often the deciding factors in determining whether a zone will produce commercially. The minimum logging program needed

Fett

1980-01-01

281

Interactive Reflective Logs  

ERIC Educational Resources Information Center

The authors created an interactive reflective log (IRL) to provide teachers with an opportunity to use a journal approach to record, evaluate, and communicate student understanding of science concepts. Unlike a traditional journal, the IRL incorporates prompts to encourage students to discuss their understanding of science content and science…

Deaton, Cynthia Minchew; Deaton, Benjamin E.; Leland, Katina

2010-01-01

282

Logging on to Learn  

ERIC Educational Resources Information Center

A classroom lecture at Capistrano Connections Academy in Southern California involves booting up the home computer, logging on to a Web site, and observing a teacher conducting a PowerPoint presentation of that day's lesson entirely online. Through microphone headsets, students can watch on their home computers, respond to the teacher's questions,…

Butler, Kevin

2010-01-01

283

Equipment for Rural Workshops.  

National Technical Information Service (NTIS)

The book is a guide to anyone who wishes to equip a workshop from the basic tools required for a one or two man carpentry workshop without power to the more sophisticated establishment requiring power equipment for both wood and metal working. Only well-k...

J. E. L. Boyd S. A. Bonnist J. R. Collett A. Mallett H. S. Pearson

1978-01-01

284

Chiral logs with staggered fermions  

NASA Astrophysics Data System (ADS)

We compute chiral logarithms in the presence of "taste" symmetry breaking of staggered fermions. The lagrangian of Lee and Sharpe is generalized and then used to calculate the logs in ? and K masses. We correct an error in Ref. [1]. MILC data with three light dynamical flavors can be well fit by our formulas. However, two new chiral parameters, which describeO( a2) hairpin diagrams for taste-nonsinglet mesons, enter in the fits. To obtain precise results for the physicalO( p4) coefficients, these new parameters will need to be bounded.

Aubin, C.; Bernard, C.; DeTar, C.; Gottlieb, Steven; Heller, Urs M.; Orginos, K.; Sugar, R.; Toussaint, D.

2003-05-01

285

Recover it yourself with user logging  

SciTech Connect

IMAGE logging is a good product that has proved to be an effective and accurate way to save interactive transactions for recovery and audit purposes. There is one shortcoming with the product in that it only logs transactions within the IMAGE domain. Some applications require that KSAM and MPE files be updated in an on-line system. How can these files be recovered. One answer is to use a recoverable program structure that not only posts the interactive transactions, but recovers them as well. The user logging facility is used to store the successful transactions to either tape or disc. This paper will discuss the recoverable program structure and the user logging subsystem.

Weir, D.

1984-01-01

286

Use of multiattribute transforms to predict log properties from seismic data  

Microsoft Academic Search

We describe a new method for predicting well-log properties from seismic data. The analysis data consist of a series of target logs from wells which tie a 3-D seis- mic volume. The target logs theoretically may be of any type; however, the greatest success to date has been in predicting porosity logs. From the 3-D seismic volume a series of

Daniel P. Hampson; James S. Schuelke; John A. Quirein

2001-01-01

287

Interpretation of ES-Logs. Final Report, October 1991-April 1995.  

National Technical Information Service (NTIS)

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Thus, these old ES-logs are an invaluable resource for the possible reentry of older field...

W. W. Whitman

1995-01-01

288

Interpretation of ES-Logs. Annual Report, October 1991-September 1992.  

National Technical Information Service (NTIS)

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Thus, these old ES-logs are an invaluable resource for the possible reentry of older field...

W. W. Whitman

1992-01-01

289

Interpretation of ES-Logs. Annual Report, October 1992-September 1993.  

National Technical Information Service (NTIS)

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Thus, these old ES-logs are an invaluable resoure for the possible reentry of older fields...

W. W. Whitman

1993-01-01

290

2. Onroom log cabin (right), log root cellar (center), tworoom ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. On-room log cabin (right), log root cellar (center), two-room log cabin (left), and post-and-beam garage (background). View to southwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

291

12. Upstream view showing thelower log pond log chute in ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. Upstream view showing thelower log pond log chute in the main channel of the Hudson River. The log chute in the dam can be seen in the background. Facing southwest. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

292

Evaluating and logging tight rocks of south Texas  

SciTech Connect

Drilling and production experience in the tight-rock oil- and gas-producing sands in south Texas have taught operators the importance of comprehensive logging programs for evaluating the formations, notes Schlumberger Well Services. Sample logs from throughout the play show that porosity and shaliness are often the deciding factors in determining whether a zone will produce commercially. The minimum logging program needed to evaluate tight-rock sands includes an induction-resistivity log and a compensated density-neutron-gamma-ray log.

Fett, T.H.

1980-02-01

293

Review of Log Sort Yards.  

National Technical Information Service (NTIS)

This report provides a general overview of current log sort yard operations in the United States, including an extensive literature review and information collected during on-site visits to several operations throughout the nation. Log sort yards provide ...

J. R. Dramm G. L. Jackson J. Wong

2002-01-01

294

Purchasing Equipment.  

ERIC Educational Resources Information Center

Illustrates pressure tactics used by salespersons bidding to sell phototypesetting equipment to a university publications operation. Contains a list of 10 recommendations to other small universities entering similar situations. (RL)

Marcello, Lesley Wharton

1981-01-01

295

Aircraft equipment  

NASA Technical Reports Server (NTRS)

The complex of functionally interconnected instruments and devices for controlling flight, engine operations, electrical systems, communications, and vital systems for passengers and crew is described. The aggregates of the aircraft automatic equipment are also discussed.

1977-01-01

296

Log Monitors in BSD UNIX  

Microsoft Academic Search

A log monitor is a process, or daemon, which monitors log messages produced by a computer system and the programs which run on it. A properly designed log monitor can recognize unusual activity (or inactivity), alert an administrator to problems, gather statistics about system activity, and\\/or take automatic action to contain a threat. It can even \\

Brett Glass

2002-01-01

297

Selective Logging, Fire, and Biomass in Amazonia  

NASA Technical Reports Server (NTRS)

Biomass and rates of disturbance are major factors in determining the net flux of carbon between terrestrial ecosystems and the atmosphere, and neither of them is well known for most of the earth's surface. Satellite data over large areas are beginning to be used systematically to measure rates of two of the most important types of disturbance, deforestation and reforestation, but these are not the only types of disturbance that affect carbon storage. Other examples include selective logging and fire. In northern mid-latitude forests, logging and subsequent regrowth of forests have, in recent decades, contributed more to the net flux of carbon between terrestrial ecosystems and the atmosphere than any other type of land use. In the tropics logging is also becoming increasingly important. According to the FAO/UNEP assessment of tropical forests, about 25% of total area of productive forests have been logged one or more times in the 60-80 years before 1980. The fraction must be considerably greater at present. Thus, deforestation by itself accounts for only a portion of the emissions carbon from land. Furthermore, as rates of deforestation become more accurately measured with satellites, uncertainty in biomass will become the major factor accounting for the remaining uncertainty in estimates of carbon flux. An approach is needed for determining the biomass of terrestrial ecosystems. 3 Selective logging is increasingly important in Amazonia, yet it has not been included in region-wide, satellite-based assessments of land-cover change, in part because it is not as striking as deforestation. Nevertheless, logging affects terrestrial carbon storage both directly and indirectly. Besides the losses of carbon directly associated with selective logging, logging also increases the likelihood of fire.

Houghton, R. A.

1999-01-01

298

Hanford wells  

SciTech Connect

The Site Characterization and Assessment Section of the Geosciences Department at Pacific Northwest Laboratory (PNL) has compiled a list of wells located on or near the Hanford Site. Information has been updated on wells existing from the days before construction of the Hanford Works to the present. This work was funded by the US Department of Energy (DOE). The list of wells will be used by DOE contractors who need condensed, tabular information on well location, construction, and completion dates. This report does not include data on lithologic logs and ground-water contamination. Moreover, the completeness of this list is limited because of new well construction and existing well modifications, which are continually under way. Despite these limitations, this list represents the most complete description possible of data pertaining to wells on or adjacent to the Hanford Site. 7 refs., 1 fig., 2 tabs.

McGhan, V.L.

1989-06-01

299

Geophysical logs in British stratigraphy  

SciTech Connect

This Special Report outlines the stratigraphic applications of the main geophysical logging tools. It characterises the British geological succession by means of the geophysical log signatures of its principle constituent formations. A large amount of previously unpublished data is provided on a geographical area long known for its importance in the development of the science of stratigraphy. The book in units modern developments of petroleum industry geophysical techniques with long-established stratigraphical discovery/research. Contents include: Introduction; Types of logs commonly used; Some geological uses of geophysical logs; Log signatures in British Stratigraphy; References.

Whittaker, A.; Holliday, D.W.; Penn, I.E.

1985-01-01

300

The X-ray log N-log S relation. [background radiation in extragalactic media  

NASA Technical Reports Server (NTRS)

Results from various surveys are reviewed as regards X-ray source counts at high galactic latitudes and the luminosity functions determined for extragalactic sources. Constraints on the associated log N-log S relation provided by the extragalactic X-ray background are emphasized in terms of its spatial fluctuations and spectrum as well as absolute flux level. The large number of sources required for this background suggests that there is not a sharp boundary in the redshift distribution of visible matter.

Boldt, Elihu

1989-01-01

301

The Lincoln Log  

NSDL National Science Digital Library

What exactly was Abraham Lincoln doing on June 11, 1850? As it turns out, he was writing a letter to one Nathaniel Hay, describing the details of a potential home-improvement project. If you're looking for more details on Lincoln's daily doings, click on over to The Lincoln Log. The information on the site was compiled by the Lincoln Sesquicentennial Commission, and in 2003, the materials were redesigned by the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign. Visitors to the site can find out what Lincoln was doing on a particular day by using the drop-down menus on the homepage, and they can also browse by year or click on the "Today's Date in Lincoln's Life" section. Also, visitors can use the "Browse New Entries" to look over newly added materials.

302

Solar Equipment  

NASA Technical Reports Server (NTRS)

A medical refrigeration and a water pump both powered by solar cells that convert sunlight directly into electricity are among the line of solar powered equipment manufactured by IUS (Independent Utility Systems) for use in areas where conventional power is not available. IUS benefited from NASA technology incorporated in the solar panel design and from assistance provided by Kerr Industrial Applications Center.

1983-01-01

303

Radiographic equipment  

US Patent & Trademark Office Database

The invention concerns radiographic equipment. The equipment includes a source of substantially mono-energetic fast neutrons produced via the deuterium-tritium or deuterium-deuterium fusion reactions, comprising a sealed-tube or similar generator for producing the neutrons. The equipment further includes a source of X-rays or gamma-rays of sufficient energy to substantially penetrate an object to be imaged and a collimating block surrounding the neutron and gamma-ray sources, apart from the provision of one or more slots emitting substantially fan-shaped radiation beams. Further included is a detector array comprising a multiplicity of individual scintillator pixels to receive radiation energy from the sources and convert the received energy into light pulses, the detector array aligned with the fan-shaped beams emitted from the source collimator and collimated to substantially prevent radiation other than that directly transmitted from the sources reaching the array. Conversion means are included for converting the light pulses produced in the scintillators into electrical signals. Conveying means are included for conveying an object between the sources and the detector array. Computing means are included for determining from the electrical signals the attenuation of the neutrons and the X-ray or gamma-ray beams and to generate output representing the mass distribution and composition of the object interposed between the source and detector array. The equipment further includes a display means for displaying images based on the mass distribution and the composition of the object being scanned.

2007-12-25

304

Methods of interpreting wireline logs in an igneous reservoir  

SciTech Connect

New interpretation methods were derived for log evaluation in a reservoir composed of igneous rock. The hydrocarbon reservoir studied was the fractured igneous basement rocks that produce in the Panhandle field in Texas. The need to locate concentrations of natural fractures, recognize petrographic differences, and possibly determine fracture mineralogy created the need for improved interpretation of existing standard logs. Logs used in this project were Dual Laterolog/Micro Spherically Focused Log, compensated neutron/lithodensity, density, natural gamma spectroscopy, continuous dipmeter, lithology analysis, oriented microresistivity, bond, and associated caliper logs. Many of the logs give similar information on reservoir parameters, but each provides uniquely useful data. Fracture occurrence can be determined from most of the logs, but a comparison of all logs yielded methods for qualitatively evaluating such features. With such a cross section of referenced data, they can better evaluate reservoir quality from fewer key logs, which reduces logging costs with no loss of understanding in evaluating a well. Completion procedures and costs can be better controlled in wells when the reservoir is more fully understood. Although the study focused on only one area, the basic observations should be applicable in similar areas.

Weimer, B.A.; Manwaring, M.S. (K. P. Exploration, Inc., Oklahoma City, OK (USA))

1987-02-01

305

Hanford wells  

SciTech Connect

Records describing wells located on or near the Hanford Site have been maintained by Pacific Northwest Laboratory and the operating contractor, Westinghouse Hanford Company. In support of the Ground-Water Surveillance Project, portions of the data contained in these records have been compiled into the following report, which is intended to be used by those needing a condensed, tabular summary of well location and basic construction information. The wells listed in this report were constructed over a period of time spanning almost 70 years. Data included in this report were retrieved from the Hanford Envirorunental Information System (HEIS) database and supplemented with information not yet entered into HEIS. While considerable effort has been made to obtain the most accurate and complete tabulations possible of the Hanford Site wells, omissions and errors may exist. This document does not include data on lithologic logs, ground-water analyses, or specific well completion details.

Chamness, M.A.; Merz, J.K.

1993-08-01

306

Tracking equipment on hire  

SciTech Connect

The first comprehensive computer-based system for managing large inventories of rental equipment in the North Sea has been commissioned by British oilfield services group Expro. Now, after a year of operations in which the system has proved its worth in improving the efficiency of Expro's well testing and other services, it is being offered for sale to other oil industry companies with problems in controlling movement of capital equipment. The computer-based inventory control system to is described.

Not Available

1985-06-01

307

Borehole Calibration Facilities to Support Gamma Logging for Hanford Subsurface Investigation and Contaminant Monitoring - 13516  

SciTech Connect

Repeated gamma logging in cased holes represents a cost-effective means to monitor gamma-emitting contamination in the deep vadose zone over time. Careful calibration and standardization of gamma log results are required to track changes and to compare results over time from different detectors and logging systems. This paper provides a summary description of Hanford facilities currently available for calibration of logging equipment. Ideally, all logging organizations conducting borehole gamma measurements at the Hanford Site will take advantage of these facilities to produce standardized and comparable results. (authors)

McCain, R.G.; Henwood, P.D.; Pope, A.D.; Pearson, A.W. [S M Stoller Corporation, 2439 Robertson Drive, Richland, WA 99354 (United States)] [S M Stoller Corporation, 2439 Robertson Drive, Richland, WA 99354 (United States)

2013-07-01

308

Treatment of Log Yard Runoff in an Aerobic Trickling Filter  

Microsoft Academic Search

Contaminated stormwater runoff from log yards is generated when precipitation comes into contact with wood, woody debris and equipment at outdoor wood sorting, processing and storage facilities. Nine runoff samples collected at a sawmill had biochemical oxygen demand (BOD), chemical oxygen demand (COD), tannins and lignin (T+L), and total suspended solids (TSS) levels ranging from 25 to 745 mg\\/L, 125

Christine Woodhouse; Sheldon J. B. Duff

2004-01-01

309

Oracle Log Buffer Queueing  

SciTech Connect

The purpose of this document is to investigate Oracle database log buffer queuing and its affect on the ability to load data using a specialized data loading system. Experiments were carried out on a Linux system using an Oracle 9.2 database. Previous experiments on a Sun 4800 running Solaris had shown that 100,000 entities per minute was an achievable rate. The question was then asked, can we do this on Linux, and where are the bottlenecks? A secondary question was also lurking, how can the loading be further scaled to handle even higher throughput requirements? Testing was conducted using a Dell PowerEdge 6650 server with four CPUs and a Dell PowerVault 220s RAID array with 14 36GB drives and 128 MB of cache. Oracle Enterprise Edition 9.2.0.4 was used for the database and Red Hat Linux Advanced Server 2.1 was used for the operating system. This document will detail the maximum observed throughputs using the same test suite that was used for the Sun tests. A detailed description of the testing performed along with an analysis of bottlenecks encountered will be made. Issues related to Oracle and Linux will also be detailed and some recommendations based on the findings.

Rivenes, A S

2004-12-08

310

Logging concessions enable illegal logging crisis in the peruvian Amazon.  

PubMed

The Peruvian Amazon is an important arena in global efforts to promote sustainable logging in the tropics. Despite recent efforts to achieve sustainability, such as provisions in the US-Peru Trade Promotion Agreement, illegal logging continues to plague the region. We present evidence that Peru's legal logging concession system is enabling the widespread illegal logging via the regulatory documents designed to ensure sustainable logging. Analyzing official government data, we found that 68.3% of all concessions supervised by authorities were suspected of major violations. Of the 609 total concessions, nearly 30% have been cancelled for violations and we expect this percentage to increase as investigations continue. Moreover, the nature of the violations indicate that the permits associated with legal concessions are used to harvest trees in unauthorized areas, thus threatening all forested areas. Many of the violations pertain to the illegal extraction of CITES-listed timber species outside authorized areas. These findings highlight the need for additional reforms. PMID:24743552

Finer, Matt; Jenkins, Clinton N; Sky, Melissa A Blue; Pine, Justin

2014-01-01

311

Logging Concessions Enable Illegal Logging Crisis in the Peruvian Amazon  

NASA Astrophysics Data System (ADS)

The Peruvian Amazon is an important arena in global efforts to promote sustainable logging in the tropics. Despite recent efforts to achieve sustainability, such as provisions in the US-Peru Trade Promotion Agreement, illegal logging continues to plague the region. We present evidence that Peru's legal logging concession system is enabling the widespread illegal logging via the regulatory documents designed to ensure sustainable logging. Analyzing official government data, we found that 68.3% of all concessions supervised by authorities were suspected of major violations. Of the 609 total concessions, nearly 30% have been cancelled for violations and we expect this percentage to increase as investigations continue. Moreover, the nature of the violations indicate that the permits associated with legal concessions are used to harvest trees in unauthorized areas, thus threatening all forested areas. Many of the violations pertain to the illegal extraction of CITES-listed timber species outside authorized areas. These findings highlight the need for additional reforms.

Finer, Matt; Jenkins, Clinton N.; Sky, Melissa A. Blue; Pine, Justin

2014-04-01

312

Console Log Keeping Made Easier - Tools and Techniques for Improving Quality of Flight Controller Activity Logs  

NASA Technical Reports Server (NTRS)

At the Marshall Space Flight Center's (MSFC) Payload Operations Integration Center (POIC) for International Space Station (ISS), each flight controller maintains detailed logs of activities and communications at their console position. These logs are critical for accurately controlling flight in real-time as well as providing a historical record and troubleshooting tool. This paper describes logging methods and electronic formats used at the POIC and provides food for thought on their strengths and limitations, plus proposes some innovative extensions. It also describes an inexpensive PC-based scheme for capturing and/or transcribing audio clips from communications consoles. Flight control activity (e.g. interpreting computer displays, entering data/issuing electronic commands, and communicating with others) can become extremely intense. It's essential to document it well, but the effort to do so may conflict with actual activity. This can be more than just annoying, as what's in the logs (or just as importantly not in them) often feeds back directly into the quality of future operations, whether short-term or long-term. In earlier programs, such as Spacelab, log keeping was done on paper, often using position-specific shorthand, and the other reader was at the mercy of the writer's penmanship. Today, user-friendly software solves the legibility problem and can automate date/time entry, but some content may take longer to finish due to individual typing speed and less use of symbols. File layout can be used to great advantage in making types of information easy to find, and creating searchable master logs for a given position is very easy and a real lifesaver in reconstructing events or researching a given topic. We'll examine log formats from several console position, and the types of information that are included and (just as importantly) excluded. We'll also look at when a summary or synopsis is effective, and when extensive detail is needed.

Scott, David W.; Underwood, Debrah (Technical Monitor)

2002-01-01

313

Thin-bed reservoir characterization using integrated three-dimensional seismic and well log data: A case study of the central Boonsville Field, Fort Worth basin, north-central Texas  

NASA Astrophysics Data System (ADS)

This dissertation is designed to resolve two problems using seismic attributes to: (1) delineate thin-bed reservoirs, and (2) distinguish thin-bed sandstone reservoirs from thin-bed non-reservoir carbonates where they appear similar at seismic scale. I evaluated some widely used techniques, developed new approaches for better imaging of thin-bed reservoirs, and found optimal attributes for thin-bed reservoir characterization. These techniques were then tested on the Pennsylvanian Caddo sequence of the Boonsville Field, Texas using public domain data. The main results found through this study are: (1) A new pattern recognition model has been developed to recognize the subtle geological and geophysical features of a thin-bed sequence based on cross-correlation of seismic traces with one or more traces believed to represent specific depositional environments. This algorithm has been proven, via the case study, to be robust and promising in defining seismic facies for subtle geological features and predicting thin-bed reservoirs. (2) Examination of the conventional thin-bed tuning model reveals that it works well only if one single thin-bed is developed or multiple thin beds are widely spaced in the sequence of interest. In other words, the model does not work for multiple closely-spaced thin-beds because of significant destructive interference. (3) A statistical inversion method was developed using the generalized regression neural network (GRNN). For a comparison study, two commercial packages were applied to the Boonsville Field data set. This study shows that all three models were able to identify the thicker reservoir sandstones and non-reservoir limestones. However, the resulting details for the thin beds vary. The GRNN method predicted the thin beds at 13 out of 20 wells with less noise and can be very useful in detecting thin-bed reservoirs in existing fields where a number of wells are available.

Xie, Deyi

314

Logging and Recovery in Prisma.  

National Technical Information Service (NTIS)

The recovery methods for main memory database systems are mostly based on maintaining a disk based log and checkpoint. The information written to the log usually consists of low level information, before/after images, or single tuple updates. The effect o...

C. A. Vandenberg M. L. Kersten

1990-01-01

315

Mining equipment  

SciTech Connect

Mining equipment for steering the cutting horizon of a mining machine cutter which is mounted on a ranging arm and which in use makes repeated traverses along the working face, comprises a boom urged into contact with the mine roof formed on a previous traverse of the machine. The boom is urged towards the mine roof by a ram hydraulically connected to a piston and cylinder device such that movement of the piston of the device is in accordance with that of the ram. Movement of the piston rod activates a flow control valve controlling operation of a ram controlling ranging of the arm.

Ford, J.A.; Whittaker, R.A.

1985-07-30

316

Deposition Equipment  

NSDL National Science Digital Library

This is a description for a learning module from Maricopa Advanced Technology Education Center. This PDF describes the module; access may be purchased by visiting the MATEC website. Use this module to develop your learners' ability to control deposition equipment operations. The activities are adaptable to cleanroom or laboratory, and employ the Applied Materials Precision 5000 as a prototypical CVD tool. The module takes learners through a review of the deposition process, an introduction to the systems and subsystems of a CVD tool, and through an entire operations cycle from recipe interpretation through process control of inputs/outputs.

2012-12-21

317

EQUIPping Teachers  

NSDL National Science Digital Library

For many years, publications such as the National Science Education Standards (NRC 1996) and The Science Teacher (TST) have encouraged teachers to focus science classes more heavily on inquiry-based instructional practice. One way to improve our teaching practice is to use a benchmark assessment to obtain a solid point of reference that honestly reflects what we do in the classroom, and then to design a developmental plan to raise the level of performance. The Electronic Quality of Inquiry Protocol (EQUIP) is helpful in providing both a benchmark and a guide to improving the quality of inquiry implemented in our classrooms.

White, Chris; Marshall, Jeff; Horton, Robert

2009-04-01

318

Estimating log models: to transform or not to transform?  

Microsoft Academic Search

Health economists often use log models to deal with skewed outcomes, such as health utilization or health expenditures. The literature provides a number of alternative estimation approaches for log models, including ordinary least-squares on ln(y) and generalized linear models. This study examines how well the alternative estimators behave econometrically in terms of bias and precision when the data are skewed

Willard G. Manning; John Mullahy

2001-01-01

319

Linear Discriminant Analysis and Discriminative Log-linear Modeling  

Microsoft Academic Search

We discuss the relationship between the discriminative training of Gaussian models and the maximum entropy framework for log-linear models. Observing that linear transforms leave the distributions resulting from the log- linear model unchanged, we derive a discriminative linear feature reduction technique from the maximum entropy ap- proach and compare it to the well-known linear discrimi- nant analysis. From experiments on

Daniel Keysers; Hermann Ney

2004-01-01

320

Mud logging principles and interpretation  

SciTech Connect

This handbook on mud logging examines the physical and chemical processes affecting hydrocarbons before and during the drilling process and in transmission to the surface. Gas-show characteristics and behavior are correlated with other borehole evidence as a means of formation evaluation. Although mud logging technology has achieved significant recent advances, the basic principles underlying the logging and interpretation of a gas show remain the same. Mud logging techniques that are recognized throughout the industry are evaluated and standards for their use and interpretation are recommended. Contents include: 1. Introduction: background, mud loggings. 2. Origins of gas shows: introduction-definitions, ''gas shows'' and ''gas kicks,'' type of gas show-sources of gas in mud, sources of gas in place. 3. Factors affecting gas shows: downhole influences-formation interaction, circulating system; surface influences-surface mud system, analysis system. 4. Oil shows: reservoir description-cuttings evaluation, hydrocarbon evaluation, solid hydrocarbons. 5. Show evaluation: interpretation-methods, examples; conclusions. Index.

Whittaker, A.

1985-01-01

321

Application of cased-hole logs to reservoir management  

SciTech Connect

Cased-hole electric wireline logs can be useful for diagnosing well problems as well as assuring optimum application of clearly defined remedial work. These logs are carefully run directly opposite points of fluid entry into the borehole. When used appropriately, interpretation is facilitated, and their subsequent application to well problems often yield positive results. The data obtained offer more definitive and more complete understanding of the production trends and the reservoir behavior. This work illustrates the interpretation and the appropriate use of various logs for identifying gas and water production problems in oil reservoirs. Examples as encountered in the Niger Delta are discussed.

Olarunsola, A.O.; Ekpo, E.U.

1984-04-01

322

Wellhead equipment support  

SciTech Connect

A wellhead assembly is described for supporting equipment in a well, comprising: a suspension nut having a threaded outer surface; a wellhead member having an inner threaded surface adapted to mesh with the threaded outer surface of the suspension nut; the suspension nut having a projection extending axially from its threaded outer surface and having an inner surface adapted to support equipment in the well; at least a portion of the inner surface for supporting the equipment facing both inwardly and upwardly such that force exerted by the weight of the equipment against the inner surface is transformed at least in part to a radially outwardly directed force; the projecting having an outer surface sized such that the outer surface is spaced from an inner surface of the wellhead member in the absence of force exerted against the inner surface of the projection such that the projection is deflected outwardly by the force exerted by the weight of the equipment against the inner surface.

Nichols, R.P.

1987-03-24

323

Final Report, Testing and Sampling Procedures for Geothermal - Geopressed Wells  

SciTech Connect

Test wells to tap and sample geothermal-geopressured formations at 15,000-20,000 feet in the Gulf Coast area can be drilled routinely utilizing available equipment and methods. Electrical logs, surveys and fluid samplers can be used to obtain accurate and reliable information as to depths, temperatures, pressures, and fluid content of the geopressured formations before the well is completed. But it will be necessary to set casing and flow the well, at least temporarily, to secure fluid production volume and pressure data to evaluate the producibility of the geopressured resource. Electric logging and wireline survey methods are fully developed techniques for measuring the parameters needed to assess a geopressured zone before setting casing. Formation subsidence, though it may be slow to develop can be measured using radioactivity tracer surveys. The reports states three conclusions. (1) Existing well logging and surveying methods and equipment are generally satisfactory for testing and sampling and sampling a geothermal-geopressured resource. (2) No significant areas of research are needed to predict, detect, and evaluate geopressured formations for their potential as geothermal resources. (3) Static and dynamic testing procedures using existing technology are satisfactory to test, sample and analyze a geopressured reservoir. [DJE 2005

Boyd, W.E.; Dorfman, M.H.; Podio, A.L.

1980-01-01

324

Grounding medium-voltage mobile or portable equipment  

Microsoft Academic Search

Examples of medium-voltage mobile equipment in pulp and paper mills include rail-mounted portal cranes for log handling, chip and bark stackers, and chip-reclaim screws. No examples of portable medium-voltage equipment can be cited. National Electrical Code (NEC) section 250-188 describes the requirements for system and equipment grounding of portable or mobile equipment rated 1 kV and higher. One of the

W. F. Robertson; J. C. Das

2000-01-01

325

Construction of permeability maps from porosity logs using fractal approach  

NASA Astrophysics Data System (ADS)

Analysis of permeability data from several wells show that permeability follows fractal behaviour. Often permeability is measured using rock samples in the laboratory or using well tests, however, such data is often very sparse and takes long time to generate such data for reservoir simulation purpose. Hence, we present an alternative approach to generate permeability maps using porosity logs from the wells. This approach relies on the fractal dimension analysis of the grain size distribution of the rock samples and tortuosity of the representative rock samples of the reservoir. Our analysis is based on the several real field well logs having porosity measurements. We have compared the permeability values obtained from fractal method from the observed values in the laboratory and it agrees very well. Hence, our method will be useful in generating reliable permeability maps for the reservoir simulation from easily available porosity (Neutron and Density logs) logs.

Dimri, V. P.

2012-12-01

326

Technology Transfer via Value-Added Log Processing. Final Report, September 1994-December 1995.  

National Technical Information Service (NTIS)

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Software has been developed to predict an earth model directly for the individual curves i...

W. W. Whitman

1995-01-01

327

Inflow and outflow signatures in flowing wellbore electrical conductivity logs  

SciTech Connect

Flowing wellbore electrical-conductivity logging provides a means to determine hydrologic properties of fractures, fracture zones, or other permeable layers intersecting a borehole in saturated rock. The method involves analyzing the time-evolution of fluid electrical-conductivity logs obtained while the well is being pumped and yields information on the location, hydraulic transmissivity, and salinity of permeable layers, as well as their initial (or ambient) pressure head. Earlier analysis methods were restricted to the case in which flows from the permeable layers or fractures were directed into the borehole. More recently, a numerical model for simulating flowing-conductivity logging was adapted to permit treatment of both inflow and outflow, including analysis of natural regional flow in the permeable layer. However, determining the fracture properties with the numerical model by optimizing the match to the conductivity logs is a laborious trial-and-error procedure. In this paper, we identify the signatures of various inflow and outflow features in the conductivity logs to expedite this procedure and to provide physical insight for the analysis of these logs. Generally, inflow points are found to produce a distinctive signature on the conductivity logs themselves, enabling the determination of location, inflow rate, and ion concentration in a straightforward manner. Identifying outflow locations and flow rates, on the other hand, can be done with a more complicated integral method. Running a set of several conductivity logs with different pumping rates (e.g., half and double the original pumping rate) provides further information on the nature of the feed points. In addition to enabling the estimation of flow parameters from conductivity logs, an understanding of the conductivity log signatures can aid in the design of follow-up logging activities.

Doughty, Christine; Tsang, Chin-Fu

2002-08-28

328

Neutron-Excited Gamma-Ray Spectrometry for Well Logging  

Microsoft Academic Search

The location and monitoring of oil reserves in cased boreholes is becoming an increasingly important activity in the petroleum industry. Measurement of the macroscopic thermal-neutron capture cross-section of the formation surrounding the bore-hole has been quite successful in differentiating between oil and saline formation water in known lithologies. However, in many instances, the formation water salinity is low, variable, or

R. C. Hertzog; R. E. Plasek

1979-01-01

329

Numerical simulation of responses for cased-hole density logging  

NASA Astrophysics Data System (ADS)

Stabilizing or stimulating oil production in old oil fields requires density logging in cased holes where open-hole logging data are either missing or of bad quality. However, measured values from cased-hole density logging are more severely influenced by factors such as fluid, casing, cement sheath and the outer diameter of the open-hole well compared with those from open-hole logging. To correctly apply the cased-hole formation density logging data, one must eliminate these influences on the measured values and study the characteristics of how the cased-hole density logging instrument responds to these factors. In this paper, a Monte Carlo numerical simulation technique was used to calculate the responses of the far detector of a cased-hole density logging instrument to in-hole fluid, casing wall thickness, cement sheath density and the formation and thus to obtain influence rules and response coefficients. The obtained response of the detector is a function of in-hole liquid, casing wall thickness, the casing's outer diameter, cement sheath density, open-hole well diameter and formation density. The ratio of the counting rate of the detector in the calibration well to that in the measurement well was used to get a fairly simple detector response equation and the coefficients in the equation are easy to acquire. These provide a new way of calculating cased-hole density through forward modelling methods.

Wu, Wensheng; Fu, Yaping; Niu, Wei

2013-10-01

330

Determining Earthquake Recurrence Intervals from Trench Logs  

NSDL National Science Digital Library

Trench logs of the San Andreas Fault at Pallett Creek, CA are the data base for a lab or homework assignment that teaches about relative dating, radiometric dating, fault recurrence intervals and the reasons for uncertainty in predicting geologic phenomena. Students are given a trench log that includes several fault strands and dated stratigraphic horizons. They estimate the times of faulting based on bracketing ages of faulted and unfaulted strata. They compile a table with the faulting events from the trench log and additional events recognized in nearby trenches, then calculate maximum, minimum and average earthquake recurrence intervals for the San Andreas Fault in this area. They conclude by making their own prediction for the timing of the next earthquake. While basically an exercise in determining relative ages of geologic horizons and events, this assignment includes radiometric dates, recurrence intervals, and an obvious societal significance that has been well received by students. With minor modifications, this exercise has been used successfully with elementary school students through university undergraduate geology majors. Less experienced students can work in groups, with each group determining the age of a single fault strand; combining the results from different groups and calculating recurrence intervals can then be done as a class activity. University students in an introductory geology course for non-majors can add their data from the trench log to an existing table with other faulting events already provided. The exercise can be made more challenging for advanced students by using logs from several different trenches, requiring students to design the table themselves, and giving students the uncertainties for the radiometric dates rather than simple ages for the strata. Most studentsâat all levelsâare initially frustrated by their inability to determine an exact date of faulting from the available data. They gain a new appreciation for the task of the geoscientist who attempts to relate geologic phenomena to the human, rather than geologic, time scale.

331

A Guide to Hardwood Log Grading.  

National Technical Information Service (NTIS)

The report, a guide to hardwood log grading (Revised) was developed as a teaching aid and field reference in grading hardwood logs. The study outlines basic principles and gives detailed practical applications, with illustrations, in grading hardwood logs...

E. D. Rast D. L. Sonderman G. L. Gammon

1973-01-01

332

A regularity-based modeling of oil borehole logs  

NASA Astrophysics Data System (ADS)

Multifractional Brownian motions (mBms) are successfully used to describe borehole logs behavior. These local fractal models allow to investigate the depth-evolution of regularity of the logs, quantified by the Hölder exponent (H). In this study, a regularity analysis is carried out on datasets recorded in Algerian oil boreholes located in different geological settings. The obtained regularity profiles show a clear correlation with lithology. Each lithological discontinuity corresponds to a jump in H value. Moreover, for a given borehole, all the regularity logs are significantly correlated and lead to similar lithological segmentations. Therefore, the Hölderian regularity is a robust property which can be used to characterize lithological heterogeneities. However, this study does not draw any relation between the recorded physical property and its estimated regularity degree for all the analyzed logs. Keywords: well logs, regularity, Hölder exponent, multifractional Brownian motion

Gaci, Said; Zaourar, Naima

2013-04-01

333

SedMob: A mobile application for creating sedimentary logs in the field  

NASA Astrophysics Data System (ADS)

SedMob is an open-source, mobile software package for creating sedimentary logs, targeted for use in tablets and smartphones. The user can create an unlimited number of logs, save data from each bed in the log as well as export and synchronize the data with a remote server. SedMob is designed as a mobile interface to SedLog: a free multiplatform package for drawing graphic logs that runs on PC computers. Data entered into SedMob are saved in the CSV file format, fully compatible with SedLog.

Wolniewicz, Pawel

2014-05-01

334

Quality assurance for radiotherapy equipment.  

National Technical Information Service (NTIS)

The quality assurance of the radiotherapy equipment comprises all organized procedures which are needed to ensure the reliable operation of the equipment on point of view of radiation safety as well as of the required accuracy of dose to the patient. Qual...

1993-01-01

335

INSPIRE and SPIRES Log File Analysis  

SciTech Connect

SPIRES, an aging high-energy physics publication data base, is in the process of being replaced by INSPIRE. In order to ease the transition from SPIRES to INSPIRE it is important to understand user behavior and the drivers for adoption. The goal of this project was to address some questions in regards to the presumed two-thirds of the users still using SPIRES. These questions are answered through analysis of the log files from both websites. A series of scripts were developed to collect and interpret the data contained in the log files. The common search patterns and usage comparisons are made between INSPIRE and SPIRES, and a method for detecting user frustration is presented. The analysis reveals a more even split than originally thought as well as the expected trend of user transition to INSPIRE.

Adams, Cole; /Wheaton Coll. /SLAC

2012-08-31

336

Aquatic Equipment Information.  

ERIC Educational Resources Information Center

Equipment usually used in water exercise programs is designed for variety, intensity, and program necessity. This guide discusses aquatic equipment under the following headings: (1) equipment design; (2) equipment principles; (3) precautions and contraindications; (4) population contraindications; and (5) choosing equipment. Equipment is used…

Sova, Ruth

337

Mail LOG: Program operating instructions  

NASA Technical Reports Server (NTRS)

The operating instructions for the software package, MAIL LOG, developed for the Scout Project Automatic Data System, SPADS, are provided. The program is written in FORTRAN for the PRIME 300 computer system. The MAIL LOG program has the following four modes of operation: (1) INPUT - putting new records into the data base (2) REVISE - changing or modifying existing records in the data base (3) SEARCH - finding special records existing in the data base (4) ARCHIVE - store or put away existing records in the data base. The output includes special printouts of records in the data base and results from the INPUT and SEARCH modes. The MAIL LOG data base consists of three main subfiles: Incoming and outgoing mail correspondence; Design Information Releases and Releases and Reports; and Drawings and Engineering orders.

Harris, D. K.

1979-01-01

338

Prediction from logs of recoverable hydrocarbon volume, Ordovician carbonates--Williston basin  

Microsoft Academic Search

The objective of this study was to develop techniques for predicting from well logs the quantity of recoverable oil by primary depletion from the upper Red River Formation (Cedar Creek Anticline) in the Williston Basin. Means of providing appropriate rock-type zonation from routinely run logs for geological purposes were also desired. A technique for calculating from logs and ratio K\\/theta

G. R. Pickett; D. S. Artus

1968-01-01

339

47 CFR 73.1820 - Station log.  

Code of Federal Regulations, 2013 CFR

...log. (a) Entries must be made in the station log either manually by a person designated...of observation must be included in each log entry. The following information...small make the required entries in the log manually at that time; (5)...

2013-10-01

340

A composite lithology log while drilling  

SciTech Connect

A new method for producing a computerized composite lithology log (CLL) while drilling by integrating MWD (measurement while drilling) and surface data is described. The CLL integrates three types of data (MWD mechanical, MWD geophysical, and surface cuttings) acquired during drilling, in three time stages: (1) Real Time. MWD drilling mechanical data including the rate of penetration and the downhole torque. This stage would provide bed boundaries and some inferred lithology. This would assist the driller with immediate drilling decisions and determine formation tops for coring, casing point, and correlation. (2) MWD Time. Recomputation of the above by adding MWD geophysical data (gamma-ray, resistivity, neutron-density). This stage would upgrade the lithology inference, and give higher resolution of bed boundaries. (3) Lag Time. Detailed analysis of surface cuttings to confirm the inferred lithologies. This last input will result in a high-quality CLL with accurate lithologies and bed boundaries. The log will serve the geologist as well as the driller, petrophysicist, and reservoir engineer. It will form the basis for more comprehensive formation evaluation while drilling by adding hydrocarbon and MWD log data.

Tannenbaum, E.; Sutcliffe, B.; Franks, A.

1988-02-01

341

A composite lithology log while drilling  

SciTech Connect

A new method for producing a computerized composite lithology log (CLL) while drilling by integrating MWD (measurement while drilling) and surface data is described. At present, lithology logs are produced at the well site by mud loggers. They provide basic description and relative amounts of lithologies. Major difficulties are encountered in relating the cuttings to their original formations due to mixing in the drilling mud while transporting to the surface, sloughing shales, flawed sampling, etc. This results in a poor control on the stratigraphic sequence and on the depth of formation boundaries. A composite log can be produced after drilling this additional inputs such as wireline, petrography, and paleontology. This process is labor intensive and expensive. The CLL integrates three types of data (MWD mechanical, MWD geophysical, and surface cuttings) acquired during drilling, in three time stages: (1) Real Time. MWD drilling mechanical data including the rate of penetration and the downhole torque. This stage would provide bed boundaries and some inferred lithology. This would assist the driller with immediate drilling decisions and determine formation tops for coring, casing point, and correlation. (2) MWD Time. Recomputation of the above by adding MWD geophysical data (gamma-ray, resistivity, neutron-density). This stage would upgrade the lithology inference, and give higher resolution to bed boundaries, (3) Lag Time. Detailed analysis of surface cuttings to confirm the inferred lithologies. This last input results in a high-quality CLL with accurate lithologies and bed boundaries.

Tannenbaum, E.; Sutcliffe, B.; Franks, A.

1988-01-01

342

Enhanced resolution processing of compensated neutron logs  

SciTech Connect

Compensated neutron logging (CNL) uses a two-detector system that was developed to reduce borehole effects. The ratio of counting rates from the detectors provides the basic tool response from which a porosity index is obtained. Each detector in this system has a different vertical resolution because of its spacing. A new method of processing the counting rates has been developed to enhance the vertical resolution capabilities of the neutron porosity index by exploiting the better vertical resolution of the near detector. Because no additional or new measurements are required, data from older wells can easily be re-evaluated. Results from the new method have been compared with microspherically focused logs (MicroSFL) and electromagnetic propagation logs (EPT). They show repeatable thin-bed resolution on the order of 1 ft (0.3 m) for data sampled at 6-in. (15-cm) intervals; the typical vertical resolution from ratio processing is approximately 2 ft (0.6 m). The statistical precision of the high-resolution processing is superior to that of the standard ratio method. An additional parameter, obtained with the new processing method, provides information about borehole effects. This parameters can be used for qualitative indications of gas when invasion is not deep and environmental effects are not large. The new method has been applied successfully in carbonate and laminated sand formations. Studies show that thin beds can be detected in high-porosity formations where normal processing has significant statistical variations resulting from reduced counting rates.

Galford, J.E.; Flaum, C.; Gilchrist, W.A. Jr.; Duckett, S.W.

1989-06-01

343

Query clustering using user logs  

Microsoft Academic Search

Query clustering is a process used to discover frequently asked questions or most popular topics on a search engine. This process is crucial for search engines based on question-answering. Because of the short lengths of queries, approaches based on keywords are not suitable for query clustering. This paper describes a new query clustering method that makes use of user logs

Ji-rong Wen; Jian-yun Nie; Hong-Jiang Zhang

2002-01-01

344

A New Approach to Logging.  

ERIC Educational Resources Information Center

In response to high numbers of preventable fatal accidents in the logging industry, the Occupational Safety and Health Administration (OSHA) developed a week-long logger safety training program that includes hands-on learning of safety techniques in the woods. Reaching small operators has been challenging; outreach initiatives in Maine, North…

Miles, Donna

2001-01-01

345

CRYPTOSPORIDIUM LOG INACTIVATION CALCULATION METHODS  

EPA Science Inventory

Appendix O of the Surface Water Treatment Rule (SWTR) Guidance Manual introduces the CeffT10 (i.e., reaction zone outlet C value and T10 time) method for calculating ozone CT value and Giardia and virus log inactivation. The LT2ESWTR Pre-proposal Draft Regulatory Language for St...

346

Downhole Memory-Logging Tools  

SciTech Connect

Logging technologies developed for hydrocarbon resource evaluation have not migrated into geothermal applications even though data so obtained would strengthen reservoir characterization efforts. Two causative issues have impeded progress: (1) there is a general lack of vetted, high-temperature instrumentation, and (2) the interpretation of log data generated in a geothermal formation is in its infancy. Memory-logging tools provide a path around the first obstacle by providing quality data at a low cost. These tools feature onboard computers that process and store data, and newer systems may be programmed to make ''decisions''. Since memory tools are completely self-contained, they are readily deployed using the slick line found on most drilling locations. They have proven to be rugged, and a minimum training program is required for operator personnel. Present tools measure properties such as temperature and pressure, and the development of noise, deviation, and fluid conductivity logs based on existing hardware is relatively easy. A more complex geochemical tool aimed at a quantitative analysis of potassium, uranium and thorium will be available in about one year, and it is expandable into all nuclear measurements common in the hydrocarbon industry. A second tool designed to sample fluids at conditions exceeding 400 C (752 F) is in the proposal stage. Partnerships are being formed between the geothermal industry, scientific drilling programs, and the national laboratories to define and develop inversion algorithms relating raw tool data to more pertinent information.

Lysne, Peter

1992-03-24

347

Downhole memory-logging tools  

SciTech Connect

Logging technologies developed hydrocarbon resource evaluation have not migrated into geothermal applications even though data so obtained would strengthen reservoir characterization efforts. Two causative issues have impeded progress: (i) there is a general lack of vetted, high-temperature instrumentation, and (ii) the interpretation of log data generated in a geothermal formation is in its infancy. Memory-logging tools provide a path around the first obstacle by providing quality data at a low cost. These tools feature on-board computers that process and store data, and newer systems may be programmed to make decisions.'' Since memory tools are completely self-contained, they are readily deployed using the slick line found on most drilling locations. They have proven to be rugged, and a minimum training program is required for operator personnel. Present tools measure properties such as temperature and pressure, and the development of noise, deviation, and fluid conductivity logs based on existing hardware is relatively easy. A more complex geochemical tool aimed at a quantitative analysis of potassium, uranium and thorium will be available in about on year, and it is expandable into all nuclear measurements common in the hydrocarbon industry. A second tool designed to sample fluids at conditions exceeding 400{degrees}C is in the proposal stage. Partnerships are being formed between the geothermal industry, scientific drilling programs, and the national laboratories to define and develop inversion algorithms relating raw tool data to more pertinent information. 8 refs.

Lysne, P.

1992-01-01

348

Continuous shear wave logging apparatus  

SciTech Connect

Apparatus for continuous shear wave logging of a borehole consisting of a sonde instrument having retractable, expandable coupling arms for rigidly engaging the borehole wall to exert repetitive torqueing action while continuously moving uphole. The sonde includes spaced detector coupling arms in continual contact with the borehole wall and polarized for detection of the repetitive propagated shear waves.

Brown, G. L.

1985-10-29

349

A model for classifying and interpreting logs of boreholes that intersect faults in stratified rocks  

SciTech Connect

A model reveals eleven fundamental relationships between the character of well logs and the geometry of borehole-strata-fault (BSF) intersections. Within limits, the model has two important practical applications. First, it provides a convenient way to classify logs of boreholes that intersect faults in stratified rocks. The different kinds of logs are given names, which can be used in informal and formal discourse to succinctly describe faulted logs. Second, the model can be used to interpret the geometry of BSF intersections directly from well logs. Knowledge of BSF geometry can be useful in interpreting faults in structure. Persons involved in highly deviated and horizontal boreholes should find the model particularly helpful.

Mulvany, P.S. (Ladd Petroleum Corp., Tulsa, OK (United States))

1992-06-01

350

Monte Carlo simulation of the neutron lifetime logging tool  

Microsoft Academic Search

The decay time of neutron pulses in a medium provides a measure of the macroscopic capture cross section of the medium. This principle has long been exploited in oil well logging to differentiate between hydrocarbon-bearing rock formations and water-bearing formations and to detect changes in the water saturation during the production period. The logging tool typically contains a 14-MeV pulsed

H. K. Choi; R. P. Gardner; K. Verghese

1986-01-01

351

Local regularity analysis of strata heterogeneities from sonic logs  

Microsoft Academic Search

Borehole logs provide geological information about the rocks crossed by the wells. Several properties of rocks can be interpreted in terms of lithology, type and quantity of the fluid filling the pores and fractures. Here, the logs are assumed to be nonhomogeneous Brownian motions (nhBms) which are generalized fractional Brownian motions (fBms) indexed by depth-dependent Hurst parameters H(z). Three techniques,

S. Gaci; N. Zaourar; M. Hamoudi; M. Holschneider

2010-01-01

352

Log-concave probability and its applications  

Microsoft Academic Search

In many applications, assumptions about the log-concavity of a probability distribution allow just enough special structure to yield a workable theory. This paper catalogs a series of theorems relating log-concavity and\\/or log-convexity of probability density functions, distribution functions, reliability functions, and their integrals. We list a large number of commonly-used probability distributions and report the log-concavity or log-convexity of their

Mark Bagnoli; Ted Bergstrom

1989-01-01

353

Selection of equipment for equipment qualification.  

National Technical Information Service (NTIS)

This report describes the methodology applied in selecting equipment in the special safety systems for equipment qualification in the CANDU 600 MW nuclear generating stations at Gentilly 2 and Point Lepreau. Included is an explanation of the selection pro...

K. G. Torr

1989-01-01

354

Dipole dispersion crossover and sonic logs in a limestone reservoir  

Microsoft Academic Search

Analyses of sonic logs in a horizontal well provide new information about mechanical properties of rocks, made possible by recent developments in their understanding of acoustic wave propagation in prestressed formations. Most sections of this horizontal well exhibit azimuthal shear isotropy, indicating isotropic stresses in the plane perpendicular to the well trajectory, leading to stable wellbore conditions. However, two sections

Bikash K. Sinha; Michael R. Kane; Bernard Frignet

2000-01-01

355

VAFLE: visual analytics of firewall log events  

NASA Astrophysics Data System (ADS)

In this work, we present VAFLE, an interactive network security visualization prototype for the analysis of firewall log events. Keeping it simple yet effective for analysts, we provide multiple coordinated interactive visualizations augmented with clustering capabilities customized to support anomaly detection and cyber situation awareness. We evaluate the usefulness of the prototype in a use case with network traffic datasets from previous VAST Challenges, illustrating its effectiveness at promoting fast and well-informed decisions. We explain how a security analyst may spot suspicious traffic using VAFLE. We further assess its usefulness through a qualitative evaluation involving network security experts, whose feedback is reported and discussed.

Ghoniem, Mohammad; Shurkhovetskyy, Georgiy; Bahey, Ahmed; Otjacques, Benoît.

2013-12-01

356

Research Equipment Funding  

NSF Publications Database

RESEARCH EQUIPMENT FUNDING CHEMICAL & TRANSPORT SYSTEMS DIVISION NATIONAL SCIENCE FOUNDATION The ... for significant research equipment expenditures through the Major Research Instrumentation Program ...

357

An Analysis of Main-Memory and Log Space Usage in Extended Ephemeral Logging  

Microsoft Academic Search

Extended Ephemeral Logging (XEL) is a database logging and recovery technique which manages a log of recovery data by partitioning\\u000a it into a series of logically circular generations. XEL copies longer-lived log data from one generation to another in order\\u000a to reclaim more quickly the space occupied by shorter-lived log data. As a result of copying, records in the log

Richard D. Regan; Alex Delis

2001-01-01

358

Electromagnetic-induction logging to monitor changing chloride concentrations  

USGS Publications Warehouse

Water from the San Joaquin Delta, having chloride concentrations up to 3590 mg/L, has intruded fresh water aquifers underlying Stockton, California. Changes in chloride concentrations at depth within these aquifers were evaluated using sequential electromagnetic (EM) induction logs collected during 2004 through 2007 at seven multiple-well sites as deep as 268 m. Sequential EM logging is useful for identifying changes in groundwater quality through polyvinyl chloride-cased wells in intervals not screened by wells. These unscreened intervals represent more than 90% of the aquifer at the sites studied. Sequential EM logging suggested degrading groundwater quality in numerous thin intervals, typically between 1 and 7 m in thickness, especially in the northern part of the study area. Some of these intervals were unscreened by wells, and would not have been identified by traditional groundwater sample collection. Sequential logging also identified intervals with improving water quality—possibly due to groundwater management practices that have limited pumping and promoted artificial recharge. EM resistivity was correlated with chloride concentrations in sampled wells and in water from core material. Natural gamma log data were used to account for the effect of aquifer lithology on EM resistivity. Results of this study show that a sequential EM logging is useful for identifying and monitoring the movement of high-chloride water, having lower salinities and chloride concentrations than sea water, in aquifer intervals not screened by wells, and that increases in chloride in water from wells in the area are consistent with high-chloride water originating from the San Joaquin Delta rather than from the underlying saline aquifer.

Metzger, Loren F.; Izbicki, John A.

2013-01-01

359

High-Resolution Flow Logging for Hydraulic Characterization of Boreholes and Aquifer Flow Zones at Contaminated Bedrock Sites  

NASA Astrophysics Data System (ADS)

In the past, flow logging was largely restricted to the application of spinner flowmeters to determine flow-zone contributions in large-diameter production wells screened in highly transmissive aquifers. Development and refinement of tool-measurement technology, field methods, and analysis techniques has greatly extended and enhanced flow logging to include the hydraulic characterization of boreholes and aquifer flow zones at contaminated bedrock sites. State-of-the-art in flow logging will be reviewed, and its application to bedrock-contamination investigations will be presented. In open bedrock boreholes, vertical flows are measured with high-resolution flowmeters equipped with flexible rubber-disk diverters fitted to the nominal borehole diameters to concentrate flow through the measurement throat of the tools. Heat-pulse flowmeters measure flows in the range of 0.05 to 5 liters per minute, and electromagnetic flowmeters measure flows in the range of 0.3 to 30 liters per minute. Under ambient and low-rate stressed (either extraction or injection) conditions, stationary flowmeter measurements are collected in competent sections of the borehole between fracture zones identified on borehole-wall images. Continuous flow, fluid-resistivity, and temperature logs are collected under both sets of conditions while trolling with a combination electromagnetic flowmeter and fluid tool. Electromagnetic flowmeters are used with underfit diverters to measure flow rates greater than 30 liters per minute and suppress effects of diameter variations while trolling. A series of corrections are applied to the flow-log data to account for the zero-flow response, bypass, trolling, and borehole-diameter biases and effects. The flow logs are quantitatively analyzed by matching simulated flows computed with a numerical model to measured flows by varying the hydraulic properties (transmissivity and hydraulic head) of the flow zones. Several case studies will be presented that demonstrate the integration of flow logging in site-characterization activities framework; 2) evaluate cross-connection effects and determine flow-zone contributions to water-quality samples from open boreholes; and 3) design discrete-zone hydraulic tests and monitoring-well completions.

Williams, J. H.; Johnson, C. D.; Paillet, F. L.

2004-05-01

360

Log Sort Yard Economics, Planning, and Feasibility.  

National Technical Information Service (NTIS)

This publication discusses basic marketing and economic concepts, planning approach, and feasibility methodology for assessing log sort yard operations. Special attention is given to sorting small-diameter and underutilized logs from forest restoration, f...

J. R. Dramm R. Govett T. Bilek G. L. Jackson

2004-01-01

361

Tucker Wireline Open Hole Wireline Logging  

SciTech Connect

The Tucker Wireline unit ran a suite of open hole logs right behind the RMOTC logging contractor for comparison purposes. The tools included Dual Laterolog, Phased Induction, BHC Sonic, and Density-Porosity.

Milliken, M.

2002-05-23

362

Geophysical logging for mineral and engineering applications  

SciTech Connect

The book contains nonpetroleum logging methods and the more exotic techniques. Contents: History; Formation types; Borehole effects and mud; Electric logging systems; Radioactivity methods; Magnetic methods; Mechanical methods and sampling methods; Analog and digital systems; Interpretation methods.

Hallenburg, J.K.

1983-01-01

363

Borehole Logging from Sample Collection to Borehole Geophysics  

NSDL National Science Digital Library

In January of 2003, CSUF drilled and completed a deep multiport-monitoring well on the north side of campus. This was done in order to gain a better understanding of the local subsurface geology and groundwater conditions in and around CSUF. Samples were collected from the drill hole (boring) every 5-feet. The total depth of the well is 870 feet below ground surface (grade). Borehole geophysical data (E-log) information was collected from the boring prior to the installation of the well pipe. As you describe the soil samples, compare and contrast your findings to those of the geophysical signature (gamma-ray log) found in the accompanying "E-log" for the boring.

Laton, Richard

364

29 CFR 1918.88 - Log operations.  

Code of Federal Regulations, 2013 CFR

...LONGSHORING Handling Cargo § 1918.88 Log operations. (a) Working in holds. When loading logs into the holds of vessels and using dumper...walking and working surface and that is used in the loading of logs onto vessels from the water....

2013-07-01

365

29 CFR 1917.18 - Log handling.  

Code of Federal Regulations, 2013 CFR

...binders are being removed. (c) Logs shall be hoisted by two slings...designed for safe hoisting. (d) Logs placed adjacent to vehicle curbs...over one tier high unless placed in bunks or so stacked as not to...to employees. (e) Before logs are slung up from the...

2013-07-01

366

Secure audit logs to support computer forensics  

Microsoft Academic Search

In many real-world applications, sensitive information must be kept it log files on an untrusted machine. In the event that an attacker captures this machine, we would like to guarantee that he will gain little or no information from the log files and to limit his ability to corrupt the log files. We describe a computationally cheap method for making

Bruce Schneier; John Kelsey

1999-01-01

367

A Dual Actuator Logging Disk Architecture  

Microsoft Academic Search

In this paper, we present a dual actuator logging disk ar- chitecture to minimize write access latencies. We reduce small synchronous write latency using the notion of log- ging writes, i.e. writing to free sectors near the current disk head location. However, we show through simulations that logging writes by itself is not sufficient to reduce write ac- cess latencies,

John A. Chandy

368

Dual actuator logging disk architecture and modeling  

Microsoft Academic Search

In this paper, we present a dual actuator logging disk architecture to minimize write access latencies. We reduce small synchronous write latency using the notion of logging writes, i.e. writing to free sectors near the current disk head location. However, we show through analytic models and simulations that logging writes by itself is not sufficient to reduce write access latencies,

John A. Chandy

2007-01-01

369

Data Mining of Network Logs  

NASA Technical Reports Server (NTRS)

The statement of purpose is to analyze network monitoring logs to support the computer incident response team. Specifically, gain a clear understanding of the Uniform Resource Locator (URL) and its structure, and provide a way to breakdown a URL based on protocol, host name domain name, path, and other attributes. Finally, provide a method to perform data reduction by identifying the different types of advertisements shown on a webpage for incident data analysis. The procedures used for analysis and data reduction will be a computer program which would analyze the URL and identify and advertisement links from the actual content links.

Collazo, Carlimar

2011-01-01

370

Gamma ray spectrometry logs as a hydrocarbon indicator for clastic reservoir rocks in Egypt.  

PubMed

Petroleum oil is an important source for the energy in the world. The Gulf of Suez, Nile Delta and South Valley are important regions for studying hydrocarbon potential in Egypt. A thorium normalization technique was applied on the sandstone reservoirs in the three regions to determine the hydrocarbon potentialities zones using the three spectrometric radioactive gamma ray-logs (eU, eTh and K% logs). The conventional well logs (gamma-ray, deep resistivity, shallow resistivity, neutron, density and sonic logs) are analyzed to determine the net pay zones in these wells. Indices derived from thorium normalized spectral logs indicate the hydrocarbon zones in petroleum reservoirs. The results of this technique in the three regions (Gulf of Suez, Nile Delta and South Valley) are in agreement with the results of the conventional well log analyses by ratios of 82%, 78% and 71% respectively. PMID:23306160

Al-Alfy, I M; Nabih, M A; Eysa, E A

2013-03-01

371

Dual excitation acoustic paramagnetic logging tool  

DOEpatents

New methods and apparatus are disclosed which allow measurement of the presence of oil and water in gelogical formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleous present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth's magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation. The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be preformed in open boreholes and in cased well bores. The Dual Excitation Acoustic Paramagnetic Logging Tool employing two acoustic sources is also described.

Vail, III, William B. (Bothell, WA)

1989-01-01

372

Dual excitation acoustic paramagnetic logging tool  

DOEpatents

New methods and apparatus are disclosed which allow measurement of the presence of oil and water in geological formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleons present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth's magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation. The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be performed in open boreholes and in cased well bores. The Dual Excitation Acoustic Paramagnetic Logging Tool employing two acoustic sources is also described. 6 figs.

Vail, W.B. III.

1989-02-14

373

Cosmic shear covariance: the log-normal approximation  

NASA Astrophysics Data System (ADS)

Context. Accurate estimates of the errors on the cosmological parameters inferred from cosmic shear surveys require accurate estimates of the covariance of the cosmic shear correlation functions. Aims: We seek approximations to the cosmic shear covariance that are as easy to use as the common approximations based on normal (Gaussian) statistics, but yield more accurate covariance matrices and parameter errors. Methods: We derive expressions for the cosmic shear covariance under the assumption that the underlying convergence field follows log-normal statistics. We also derive a simplified version of this log-normal approximation by only retaining the most important terms beyond normal statistics. We use numerical simulations of weak lensing to study how well the normal, log-normal, and simplified log-normal approximations as well as empirical corrections to the normal approximation proposed in the literature reproduce shear covariances for cosmic shear surveys. We also investigate the resulting confidence regions for cosmological parameters inferred from such surveys. Results: We find that the normal approximation substantially underestimates the cosmic shear covariances and the inferred parameter confidence regions, in particular for surveys with small fields of view and large galaxy densities, but also for very wide surveys. In contrast, the log-normal approximation yields more realistic covariances and confidence regions, but also requires evaluating slightly more complicated expressions. However, the simplified log-normal approximation, although as simple as the normal approximation, yields confidence regions that are almost as accurate as those obtained from the log-normal approximation. The empirical corrections to the normal approximation do not yield more accurate covariances and confidence regions than the (simplified) log-normal approximation. Moreover, they fail to produce positive-semidefinite data covariance matrices in certain cases, rendering them unusable for parameter estimation. Conclusions: The log-normal or simplified log-normal approximation should be used in favour of the normal approximation for parameter estimation and parameter error forecasts. More generally, any approximation to the cosmic shear covariance should ensure a positive-(semi)definite data covariance matrix.

Hilbert, S.; Hartlap, J.; Schneider, P.

2011-12-01

374

Improving equipment reliability through thermography  

SciTech Connect

Failure of electrical or mechanical equipment is costly to repair and also results in loss of revenue. Industries spend millions on protective devices to ensure the reliability of their equipment. Alarm systems and protective relaying safeguard against most problems. However, often permanent damage has already occurred when these systems operate. As technology develops so does the ability to suppress unexpected outages and equipment damage. In many cases an equipment problem manifests itself by the radiation of excess heat energy. The detection and analysis of this heating is becoming a major factor in predictive maintenance programs. This paper describes how thermography is a cost-effective tool to provide reliable service. This technology can work for the pipe line industry just as well as the utility industry.

Bates, D.E. (Alabama Power Co., Birmingham, AL (USA))

1990-06-01

375

Tracking the Inside Intruder Using Net Log on Debug Logging in Microsoft Windows Server Operating Systems  

SciTech Connect

In today's well-connected environments of the Internet, intranets, and extranets, protecting the Microsoft Windows network can be a daunting task for the security engineer. Intrusion Detection Systems are a must-have for most companies, but few have either the financial resources or the people resources to implement and maintain full-scale intrusion detection systems for their networks and hosts. Many will at least invest in intrusion detection for their Internet presence, but others have not yet stepped up to the plate with regard to internal intrusion detection. Unfortunately, most attacks will come from within. Microsoft Windows server operating systems are widely used across both large and small enterprises. Unfortunately, there is no intrusion detection built-in to the Windows server operating system. The security logs are valuable but can be difficult to manage even in a small to medium sized environment. So the question arises, can one effectively detect and identify an in side intruder using the native tools that come with Microsoft Windows Server operating systems? One such method is to use Net Logon Service debug logging to identify and track malicious user activity. This paper discusses how to use Net Logon debug logging to identify and track malicious user activity both in real-time and for forensic analysis.

Davis, CS

2004-01-20

376

Evaluate cement with radioactive tracers, directional gamma ray logs  

SciTech Connect

Use of radioactive tracers to evaluate hydraulic fractures has recently been extended through the use of directional gamma ray measurements. The directional gamma ray logging tool determines the azimuthal direction of gamma rays from radioactive isotope-tagged fracture proppants to estimate the fracture direction in well-controlled circumstances. The technology also provides new ways of evaluating primary and squeeze cement jobs by enhancing information from directional gamma ray data with advanced image processing techniques. By tagging the cement with a uniform quantity per unit volume of radioactivity, different levels of gamma ray log response must be attributed to variances in cement quality. Cement evaluation with tracers can help detect: thin cement sheaths; light-weight or low compressive strength cements where the acoustic impedance is near that of water; gas cut cement where the acoustic signal is attenuated; wells with microannulus that cannot be pressured to obtain valid log data; poor casing centralization; and multiple cement stage placement. The paper describes the logging tool, operational procedures, and a log example.

NONE

1996-07-01

377

Leak checker data logging system  

DOEpatents

A portable, high speed, computer-based data logging system for field testing systems or components located some distance apart employs a plurality of spaced mass spectrometers and is particularly adapted for monitoring the vacuum integrity of a long string of a superconducting magnets such as used in high energy particle accelerators. The system provides precise tracking of a gas such as helium through the magnet string when the helium is released into the vacuum by monitoring the spaced mass spectrometers allowing for control, display and storage of various parameters involved with leak detection and localization. A system user can observe the flow of helium through the magnet string on a real-time basis hour the exact moment of opening of the helium input valve. Graph reading can be normalized to compensate for magnet sections that deplete vacuum faster than other sections between testing to permit repetitive testing of vacuum integrity in reduced time.

Gannon, Jeffrey C. (Arlington, TX); Payne, John J. (Waterman, IL)

1996-01-01

378

Leak checker data logging system  

DOEpatents

A portable, high speed, computer-based data logging system for field testing systems or components located some distance apart employs a plurality of spaced mass spectrometers and is particularly adapted for monitoring the vacuum integrity of a long string of a superconducting magnets such as used in high energy particle accelerators. The system provides precise tracking of a gas such as helium through the magnet string when the helium is released into the vacuum by monitoring the spaced mass spectrometers allowing for control, display and storage of various parameters involved with leak detection and localization. A system user can observe the flow of helium through the magnet string on a real-time basis hour the exact moment of opening of the helium input valve. Graph reading can be normalized to compensate for magnet sections that deplete vacuum faster than other sections between testing to permit repetitive testing of vacuum integrity in reduced time. 18 figs.

Gannon, J.C.; Payne, J.J.

1996-09-03

379

Correlating Log Messages for System Diagnostics  

SciTech Connect

In large-scale computing systems, the sheer volume of log data generated presents daunting challenges for debugging and monitoring of these systems. The Oak Ridge Leadership Computing Facility s premier simulation platform, the Cray XT5 known as Jaguar, can generate a few hundred thousand log entries in less than a minute for many system level events. Determining the root cause of such system events requires analyzing and interpretation of a large number of log messages. Most often, the log messages are best understood when they are interpreted collectively rather than individually. In this paper, we present our approach to interpreting log messages by identifying their commonalities and grouping them into clusters. Given a set of log messages within a time interval, we group the messages based on source, target, and/or error type, and correlate the messages with hardware and application information. We monitor the Lustre log messages in the XT5 console log and show that such grouping of log messages assists in detecting the source of system events. By intelligent grouping and correlation of events in the log, we are able to provide system administrators with meaningful information in a concise format for root cause analysis.

Gunasekaran, Raghul [ORNL] [ORNL; Dillow, David A [ORNL] [ORNL; Shipman, Galen M [ORNL] [ORNL; Maxwell, Don E [ORNL] [ORNL; Hill, Jason J [ORNL] [ORNL; Park, Byung H [ORNL] [ORNL; Geist, Al [ORNL] [ORNL

2010-01-01

380

Tolerance bounds for log gamma regression models  

NASA Technical Reports Server (NTRS)

The present procedure for finding lower confidence bounds for the quantiles of Weibull populations, on the basis of the solution of a quadratic equation, is more accurate than current Monte Carlo tables and extends to any location-scale family. It is shown that this method is accurate for all members of the log gamma(K) family, where K = 1/2 to infinity, and works well for censored data, while also extending to regression data. An even more accurate procedure involving an approximation to the Lawless (1982) conditional procedure, with numerical integrations whose tables are independent of the data, is also presented. These methods are applied to the case of failure strengths of ceramic specimens from each of three billets of Si3N4, which have undergone flexural strength testing.

Jones, R. A.; Scholz, F. W.; Ossiander, M.; Shorack, G. R.

1985-01-01

381

Cleaning supplies and equipment  

MedlinePLUS

... on any object the patient touched or on equipment that was used during their care. Some germs ... why it is important to disinfect supplies and equipment. To disinfect something means to clean it to ...

382

Mobile Equipment Expands Inventory.  

ERIC Educational Resources Information Center

Describes the Mobile Equipment Modules (MEM) system in Duluth, Minnesota. MEM is a way to hold down costs and increase learning opportunities by consolidating purchases of expensive shop equipment within the school district, grouping the equipment in modules, and scheduling and moving it from school to school as needed. (MF)

McGough, Robert L.; And Others

1978-01-01

383

THE INFLUENCE OF THE BOREHOLE ENVIRONMENT UPON COMPRESSIONAL SONIC LOGS  

Microsoft Academic Search

The observed compressional sonic recorded with conventional sonic devices is affected by formation and\\/or filtrate water salinity, dissolved gas. borehole and formation temperature, pore pressure, low saturation biogenic free gas, and the presence of hydrocarbons. The magnitude of this effect is not well appreciated by users of borehole sonic logs. These factors can have a significant effect upon measured interval

Mark Alberty

1994-01-01

384

29 CFR 570.54 - Logging occupations and occupations in the operation of any sawmill, lath mill, shingle mill, or...  

Code of Federal Regulations, 2010 CFR

...of Age or Detrimental to Their Health or Well-Being § 570.54 Logging occupations...converting of timber into logs, poles, piles, ties, bolts, pulpwood, chemical wood...converting of timber into logs, poles, piles, ties, bolts, pulpwood, chemical...

2010-07-01

385

NADIR: Monitoring, Error Handling, and Logging with Tango  

NASA Astrophysics Data System (ADS)

The ingest and transport of a large amount of astronomical data, in geographically distributed archives, imply some challenging issues, like remote control and configuration, monitoring and logging anomalous conditions, fault tolerance and error handling. Based on this considerations and on our experience in data management, we started development of a New Archiving Distributed InfrastructuRe (NADIR), using Tango (Team 2013; S. Gara 2012), a well known distributed control system (DCSs) within scientific environments, taking advantage of its key features, like reliability, scalability, logging and alarm system, consolidated pattern and template, to solve this complexity. In this paper we discuss about design choices and technical aspects around this project.

De Marco, M.; Knapic, C.; Smareglia, R.

2014-05-01

386

Towards a Stochastic Cellular Automata Model of Log Wood Combustion  

NASA Astrophysics Data System (ADS)

Describing the combustion of log wood and others solid fuels with complex geometry, considerable water content and often heterogenous struture is a nontrivial task. Stochastic Cellular Automata models offer a promising approach for modelling such processes. Combustion models of this type exhibit several similarities to the well-known forest fire models, but there are also significant differences between those two types of models. These differences call for a detailed analysis and the development of supplementary modeling approaches. In this article we define a qualitative two-dimensional model of burning log wood, discuss the most important differences to classical forest fire models and present some preliminary results.

Lichtenegger, Klaus; Schappacher, Wilhelm; Hebenstreit, Babette; Schmidl, Christoph; Höftberger, Ernst

2014-03-01

387

Fundamentals of log analysis. Part 3 -- Database editing: Building a stable foundation  

SciTech Connect

Any accurate information evaluation study is built upon log, core and well test database foundation. Editing data that will become the foundation is discussed in this part of the series. The basic and environmental corrections described herein, when performed correctly, will prevent the large errors described in this paper. This paper reviews methods for flagging and removing invalid data, depth corrections, environmental corrections, and reconstruction of logs. It specifically describes density log corrections in holes where filter coke is a problem.

Hunt, E.; Pursell, D. [S.A. Holditch and Associates, Inc., College Station, TX (United States)

1996-09-01

388

Selection of equipment for equipment qualification. Research report No. INFO0302  

Microsoft Academic Search

Equipment qualification (EQ) deals with the qualification of safety-related equipment for service operation conditions under all expected service conditions in nuclear power plants. This report describes the methodology applied in selecting equipment in the special safety systems at the CANDU 600 MW nuclear generating stations at Gentilly 2 and Point Lepreau, as well as giving an explanation of the selection

Torr

1989-01-01

389

Robust Audio Watermarking Based on Log-Polar Frequency Index  

NASA Astrophysics Data System (ADS)

In this paper, we analyze the audio signal distortions introduced by pitch-scaling, random cropping and DA/AD conversion, and find a robust feature, average Fourier magnitude over the log-polar frequency index(AFM), which can resist these attacks. Theoretical analysis and extensive experiments demonstrate that AFM is an appropriate embedding region for robust audio watermarking. This is the first work on applying log-polar mapping to audio watermark. The usage of log-polar mapping in our work is basically different from the existing works in image watermarking. The log-polar mapping is only applied to the frequency index, not to the transform coefficients, which avoids the reconstruction distortion of inverse log-polar transform and reduces the computation cost. Comparison with the existing methods, the proposed AFM-based watermarking scheme has the outstanding performance on resisting pitch-scaling and random cropping, as well as very approving robustness to DA/AD conversion and TSM (Time-Scale Modification). The watermarked audio achieves high auditory quality. Experimental results show that the scheme is very robust to common audio signal processing and distortions introduced in Stirmark for Audio.

Yang, Rui; Kang, Xiangui; Huang, Jiwu

390

Calculation of porosity from nuclear magnetic resonance and conventional logs in gas-bearing reservoirs  

NASA Astrophysics Data System (ADS)

The porosity may be overestimated or underestimated when calculated from conventional logs and also underestimated when derived from nuclear magnetic resonance (NMR) logs due to the effect of the lower hydrogen index of natural gas in gas-bearing sandstones. Proceeding from the basic principle of NMR log and the results obtained from a physical rock volume model constructed on the basis of interval transit time logs, a technique of calculating porosity by combining the NMR log with the conventional interval transit time log is proposed. For wells with the NMR log acquired from the MRIL-C tool, this technique is reliable for evaluating the effect of natural gas and obtaining accurate porosity in any borehole. In wells with NMR log acquired from the CMR-Plus tool and with collapsed borehole, the NMR porosity should be first corrected by using the deep lateral resistivity log. Two field examples of tight gas sandstones in the Xujiahe Formation, central Sichuan basin, Southwest China, illustrate that the porosity calculated by using this technique matches the core analyzed results very well. Another field example of conventional gas-bearing reservoir in the Ziniquanzi Formation, southern Junggar basin, Northwest China, verifies that this technique is usable not only in tight gas sandstones, but also in any gas-bearing reservoirs.

Xiao, Liang; Mao, Zhi-qiang; Li, Gao-ren; Jin, Yan

2012-08-01

391

Optimal message log reclamation for independent checkpointing  

NASA Technical Reports Server (NTRS)

Independent (uncoordinated) check pointing for parallel and distributed systems allows maximum process autonomy but suffers from possible domino effects and the associated storage space overhead for maintaining multiple checkpoints and message logs. In most research on check pointing and recovery, it was assumed that only the checkpoints and message logs older than the global recovery line can be discarded. It is shown how recovery line transformation and decomposition can be applied to the problem of efficiently identifying all discardable message logs, thereby achieving optimal garbage collection. Communication trace-driven simulation for several parallel programs is used to show the benefits of the proposed algorithm for message log reclamation.

Wang, Yi-Min; Fuchs, W. Kent

1993-01-01

392

Selection of equipment for equipment qualification. Research report No. INFO-0302  

SciTech Connect

Equipment qualification (EQ) deals with the qualification of safety-related equipment for service operation conditions under all expected service conditions in nuclear power plants. This report describes the methodology applied in selecting equipment in the special safety systems at the CANDU 600 MW nuclear generating stations at Gentilly 2 and Point Lepreau, as well as giving an explanation of the selection procedure adopted and the rationale behind the criteria used in identifying the equipment.

Torr, K.G.

1989-01-01

393

Fatal logging injuries in Washington state, 1977 to 1983.  

PubMed

The logging fatalities in Washington state during the years 1977 to 1983 were analyzed using death certificates and the investigations of the Washington Department of Labor and Industries. Each source identified more than 92% of the 135 fatalities. The annual injury mortality rate for logging was approximately 2/1,000 workers. Loggers were killed by falling trees in 34% of fatalities and by equipment in 24% of fatalities. None of the 12 men killed in vehicle rollovers were wearing seat belts. Risk was greatest for tree fellers and choker-setters. Risk was also greatest during the morning, during the first two days of the workweek, and during the month of June. Size of logging company was inversely related to risk of injury, with the smallest companies having mortality ratios ten times higher than the largest companies. The study suggests that routinely collected occupational data on injuries and employment can be combined to identify high-risk categories in specific industries and thereby target inspection activities or suggest new regulations addressing specific occupational hazards. PMID:3819888

Paulozzi, L J

1987-02-01

394

Flow rate logging seepage meter  

NASA Technical Reports Server (NTRS)

An apparatus for remotely measuring and logging the flow rate of groundwater seepage into surface water bodies. As groundwater seeps into a cavity created by a bottomless housing, it displaces water through an inlet and into a waterproof sealed upper compartment, at which point, the water is collected by a collection bag, which is contained in a bag chamber. A magnet on the collection bag approaches a proximity switch as the collection bag fills, and eventually enables the proximity switch to activate a control circuit. The control circuit then rotates a three-way valve from the collection path to a discharge path, enables a data logger to record the time, and enables a pump, which discharges the water from the collection bag, through the three-way valve and pump, and into the sea. As the collection bag empties, the magnet leaves the proximity of the proximity switch, and the control circuit turns off the pump, resets the valve to provide a collection path, and restarts the collection cycle.

Reay, William G. (Inventor); Walthall, Harry G. (Inventor)

1996-01-01

395

Logging technology for high-temperature geothermal boreholes  

SciTech Connect

Research in materials, equipment, and instrument development was required in the Hot Dry Rock Energy Extraction Demonstration at Fenton Hill located in northern New Mexico. Results of this extensive development advanced the logging technology in geothermal boreholes to present state-of-the art. The new Phase II Energy Extraction System at the Fenton Hill Test Site will consist of two wellbores drilled to a depth of about 4570 m (15,000 ft) and then connected by a series of hydraulic-induced fractures. The first borehole (EE-2) was completed in May of 1980 at a depth of 4633 m (15,200 ft) of which approximately 3960 m (13,000 ft) is in Precambrian granitic rock. Starting at a depth of approximately 2930 m (9600 ft), the borehole was inclined up to 35/sup 0/ from vertical. Bottom-hole temperature in EE-2 is 320/sup 0/C. The EE-3 borehole was then drilled to a depth of 4236 m (13,900 ft). Its inclined part is positioned directly over the EE-2 wellbore with a vertical separation of about 450 m (1500 ft) between them. Many of the geophysical measurements needed to develop the hot dry rock concept are unique. Most of the routine instruments used in petroleum drilling fail in the hot and abrasive environment. New equipment developed includes not only the downhole sonde that houses the transducer and associated line driving electronics, but modifications also were needed on the entire data retrieval systems and associated data analysis technology. Successful performance of wellbore surveys in the EE-2 and EE-3 boreholes depended upon the capacity of the sensors, instrument sonde, cablehead, and armored logging cable to work in this severe environment. The major areas of materials development for surveying the boreholes in the high-temperature environment were on elastomeric seals, electrical insulation for logging cables, downhole sensors, and associated downhole electronic and electro-mechanical components.

Dennis, B.R.

1984-05-01

396

Interpretation of ES-logs. Annual report, October 1992-September 1993  

SciTech Connect

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Thus, these old ES-logs are an invaluable resoure for the possible reentry of older fields, but they are very difficult to interpret. Software has been developed to generate ES-logs from an earth model. Also, software has been developed to predict an earth model directly for the individual curves in an ES-log, which typically consists of three curves representing the resistivity of different volumes of rock. The generation of an ES-log from an earth model has been accomplished by numerically approximating the controlling physical relations and solving the complex of equations. The generation of an earth model for each of the curves in an ES-log has been accomplished using an iterative process known as Levenberg-Marquardt inversion. Currently, software is being developed to simultaneously invert the three ES-logs, so that possible invasion can be detected for potential interpretation as hydrocarbon or water.

Whitman, W.W.

1993-10-01

397

Interpretation of ES-logs. Annual report, October 1991-September 1992  

SciTech Connect

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Thus, these old ES-logs are an invaluable resource for the possible reentry of older fields, but they are very difficult to interpret. Software has been developed to generate ES-logs from an earth model. Also, software has been developed to predict an earth model directly for the individual curves in an ES-log, which typically consists of three curves representing the resistivity of different volumes of rock. The generation of an ES-log from an earth model has been accomplished by numerically approximating the controlling physical relations and solving the complex of equations. The generation of an earth model for each of the curves in an ES-log has been accomplished using an iterative process known as Levenberg-Marquardt inversion. Currently, software is being developed to simultaneously invert the three ES-logs, so that possible invasion can be detected for potential interpretation as hydrocarbon or water.

Whitman, W.W.

1992-10-01

398

Interpretation of ES-logs. Final report, October 1991-April 1995  

SciTech Connect

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Thus, these old ES-logs are an invaluable resource for the possible reentry of older fields, but they are very difficult to interpret. Software has been developed to generate ES-logs from an earth model. Also, software has been developed to predict an earth model directly for the individual curves in an ES-log, which typically consists of three curves representing the resistivity of different volumes of rock. The generation of an ES-log from an earth model as been accomplished by numerically approximating the controlling physical relations and solving the complex of equations. The generation of an earth model for each of the curves in an ES-log has been accomplished using an iterative process known as Levenberg-Marquardt inversion. Software has also been developed to simultaneously invert the three ES-logs, so that possible invasion can be detected and the zone evaluated for potential interpretation as hydrocarbon or water.

Whitman, W.W.

1995-04-01

399

An 0(n log n) sorting network  

Microsoft Academic Search

The purpose of this paper is to describe a sorting network of size 0(n log n) and depth 0(log n). A natural way of sorting is through consecutive halvings: determine the upper and lower halves of the set, proceed similarly within the halves, and so on. Unfortunately, while one can halve a set using only 0(n) comparisons, this cannot be

Miklós Ajtai; János Komlós; Endre Szemerédi

1983-01-01

400

Efficient distributed recovery using message logging  

Microsoft Academic Search

Absfrucf: Various distributed algorithms am presented, that allow nodes in a distributed system to recover from crash failures efficiently. The algorithms are independent of the application programs running on the nodes. The algorithms log messages and checkpoint states of the processes to stable storage at each node. Both logging of messages and checkpointing of process states can be done asynchronously

A. Prasad Sistla; Jennifer L. Welch

1989-01-01

401

System Anomaly Detection: Mining Firewall Logs  

Microsoft Academic Search

This paper describes an application of data mining and machine learning to discovering network traffic anomalies in firewall logs. There is a variety of issues and problems that can occur with systems that are protected by firewalls. These systems can be improperly configured, operate unexpected services, or fall victim to intrusion attempts. Firewall logs often generate hundreds of thousands of

Robert Winding; Timothy Wright; Michael Chapple

2006-01-01

402

Log-binomial models: exploring failed convergence  

PubMed Central

Background Relative risk is a summary metric that is commonly used in epidemiological investigations. Increasingly, epidemiologists are using log-binomial models to study the impact of a set of predictor variables on a single binary outcome, as they naturally offer relative risks. However, standard statistical software may report failed convergence when attempting to fit log-binomial models in certain settings. The methods that have been proposed in the literature for dealing with failed convergence use approximate solutions to avoid the issue. This research looks directly at the log-likelihood function for the simplest log-binomial model where failed convergence has been observed, a model with a single linear predictor with three levels. The possible causes of failed convergence are explored and potential solutions are presented for some cases. Results Among the principal causes is a failure of the fitting algorithm to converge despite the log-likelihood function having a single finite maximum. Despite these limitations, log-binomial models are a viable option for epidemiologists wishing to describe the relationship between a set of predictors and a binary outcome where relative risk is the desired summary measure. Conclusions Epidemiologists are encouraged to continue to use log-binomial models and advocate for improvements to the fitting algorithms to promote the widespread use of log-binomial models.

2013-01-01

403

Thermostable Two-Channel Radioactivity Logging Apparatus.  

National Technical Information Service (NTIS)

A thermostable two-channel radioactivity logging (RL) apparatus, designed to operate at temperatures up to 220 exp 0 C and a hydrostatic pressure up to 1200 kgf/cm exp 2, developed and produced for conducting operations by the gamma logging (GL) and neutr...

E. S. Bakhromi M. V. Posikera

1976-01-01

404

Cracking the Code: Web Log Analysis.  

ERIC Educational Resources Information Center

Demonstrates the benefits and problems of using Web log analysis to extract information about the global information customer. The Web logs examined were those of "The Times" and "Sunday Times." Highlights include the measures and metrics; the data and its meaning; and analyses with potential (AEF)

Nicholas, David; Huntington, Paul; Lievesley, Nat; Withey, Richard

1999-01-01

405

Message Logging: Pessimistic, Optimistic, Causal, and Optimal  

Microsoft Academic Search

Message-logging protocols are an integral part of a popular technique for implementing processes that can recover from crash failures. All message-logging protocols require that, when recovery is complete, there be no orphan processes, which are surviving processes whose states are inconsistent with the recovered state of a crashed process. We give a precise specification of the consistency property \\

Lorenzo Alvisi; Keith Marzullo

1998-01-01

406

Message Logging: Pessimistic, Optimistic, and Causal  

Microsoft Academic Search

Message logging protocols are an integral part of a technique for implementing processes that canrecover from crash failures. All message logging protocols require that, when recovery is complete,there be no orphan processes, which are surviving processes whose states are inconsistent with therecovered state of a crashed process. We give a precise specification of the consistency property "noorphan processes". From this

Lorenzo Alvisi; Keith Marzullot

1995-01-01

407

The Computer as a Log of Wood.  

ERIC Educational Resources Information Center

Because a teacher and a student were seated on either end of a log (facing each other), there was direct, eye-to-eye, one-on-one communication. If properly used, computers can take the place of the log, establishing the eye-to-eye, one-on-one, two-way communication. Advantages occur because computers are interactive, individualized, modular, and…

Coad, Peter; Coad, Raylene

1985-01-01

408

Deriving Software Usage Patterns from Log Files  

Microsoft Academic Search

Log files (discrete recordings of user actions during software use) offer the ability to collect human-computer interaction data on a number of users, over time, while the users are engaged in typical tasks in typical environments. The disadvantage of log files is the lack of automated methods for analyzing the volumes of data in a meaningful way. This paper presents

Mark Guzdial

1993-01-01

409

Chernoff's density is log-concave  

PubMed Central

We show that the density of Z = argmax{W (t) ? t2}, sometimes known as Chernoff’s density, is log-concave. We conjecture that Chernoff’s density is strongly log-concave or “super-Gaussian”, and provide evidence in support of the conjecture.

BALABDAOUI, FADOUA; WELLNER, JON A.

2014-01-01

410

Discover Presidential Log Cabins. Teacher's Discussion Guide.  

ERIC Educational Resources Information Center

Discover Presidential Log Cabins is a set of materials designed to help educate 6-8 grade students about the significance of three log cabin sites occupied by George Washington, Ulysses Grant, Abraham Lincoln, and Theodore Roosevelt. This teacher's discussion guide is intended for use as part of a larger, comprehensive social studies program, and…

National Park Service (Dept. of Interior), Washington, DC.

411

Memoirs of Togetherness from Audio Logs  

Microsoft Academic Search

In this paper, we propose a new concept how tempo-social information about moments of togetherness within a social group of people can be retrieved in the palm of the hand from social context. The social context is digitised by audio logging of the same user centric device such as mobile phone. Being asynchronously driven it allows automatically logging social events

Danil Korchagin

2009-01-01

412

Breaking the vicious circle of illegal logging in indonesia.  

PubMed

The government of Indonesia, which presides over 10% of the world's tropical forests, has set ambitious targets to cut its high deforestation rates through an REDD+ scheme (Reducing Emissions from Deforestation and forest Degradation). This will require strong law enforcement to succeed. Yet, strategies that have accomplished this are rare and, along with past failures, tend not to be documented. We evaluated a multistakeholder approach that seeks to tackle illegal logging in the carbon-rich province of Aceh, Sumatra. From 2008 to 2009, Fauna & Flora International established and supported a community-based informant network for the 738,000 ha Ulu Masen ecosystem. The network reported 190 forest offenses to local law enforcement agencies, which responded with 86 field operations that confiscated illicit vehicles, equipment, and timber, and arrested 138 illegal logging suspects. From 45 cases subsequently monitored, 64.4% proceeded to court, from which 90.0% of defendants received a prison sentence or a verbal warning for a first offense. Spatial analyses of illegal logging and timber storage incidents predicted that illegal activities would be more effectively deterred by law enforcement operations that targeted the storage sites. Although numerous clusters of incidents were identified, they were still widespread reflecting the ubiquity of illegal activities. The multistakeholder results were promising, but illegal logging still persisted at apparently similar levels at the project's end, indicating that efforts need to be further strengthened. Nevertheless, several actions contributed to the law enforcement achievements: strong political will; strong stakeholder support; and funding that could be promptly accessed. These factors are highlighted as prerequisites for achieving Indonesia's ambitious REDD+ goals. Rompiendo el Círculo Vicioso de la Tala Ilegal en Indonesia. PMID:24628366

Linkie, Matthew; Sloan, Sean; Kasia, Rahmad; Kiswayadi, Dedy; Azmi, Wahdi

2014-08-01

413

Using a multiple log approach to evaluate Green River oil shale in the Piceance Creek Basin  

Microsoft Academic Search

A method has been devised for predicting modified Fischer assay yield from conventional logs in the Piceance Creek Basin of Colorado. The traditional approach for using well logs to predict oil shale richness has been to relate one of the porosity tool responses to the modified Fischer assay. This approach is unsatisfactory when there is significant lithology variation in the

R. Habiger; R. H. Robinson

1983-01-01

414

88. DATA REPORT: GEOCHEMICAL LOGGING RESULTS FROM THE SEA OF JAPAN: SITES 798 AND 7991  

Microsoft Academic Search

Geochemical well logs were obtained in the sedimentary sequences drilled at Sites 798 and 799 in the Sea of Japan. The recorded data have been corrected for variations in borehole size, borehole fluid composition, downhole temperature, and logging speed and were processed to derive the concentration of the elements Th, U, and Gd and the dry weight percentages of oxides

James F. Bristow; Cristina Broglia; Peter B. deMenocal; Elizabeth Lewis Pratson

415

When do logs move in rivers?  

NASA Astrophysics Data System (ADS)

Large woody debris is an integral component of forested, fluvial systems throughout the world, yet we know little about hydraulic thresholds for movement and transport of logs. We developed theoretical models of entrainment and performed flume experiments to examine thresholds for wood movement in streams. Both the model and the experiments indicate that log entrainment is primarily a function of the piece angle relative to flow direction, whether or not the log had a rootwad, the density of the log, and the piece diameter. Stability increased if the pieces had rootwads or were rotated parallel to flow. Although previously reported as the most important factor in piece stability, piece length did not significantly affect the threshold of movement in our experiments or our physically based model, for logs shorter than channel width. These physically based models offer a first-order approach to evaluating the stability of either naturally derived woody debris or material deliberately introduced to streams for various management objectives.

Braudrick, Christian A.; Grant, Gordon E.

2000-02-01

416

30 CFR 250.502 - Equipment movement.  

Code of Federal Regulations, 2013 CFR

...well-completion rigs and related equipment on and off a platform or from well to well on the same platform, including rigging up and rigging down, shall be conducted in a safe manner. All wells in the same well-bay which are capable of producing...

2013-07-01

417

Evaluation of geophysical logs, phase I, for Crossley Farms Superfund Site, Berks County, Pennsylvania  

USGS Publications Warehouse

Twenty-one wells were drilled at Crossley Farms Superfund Site between December 15, 1987, and May 1, 1988, to define and monitor the horizontal and vertical distribution of ground-water contamination emanating from a suspected contaminant source area (Blackhead Hill). Eight well clusters were drilled on or near the Crossley Site and three well clusters were drilled at locations hydrologically down gradient from the site. Depths of wells range from 21 to 299 feet below land surface. These wells were installed in saprolite in shallow, intermediate, and deep water-producing zones of the fractured bedrock aquifer. Borehole-geophysical and video logging were conducted between April 24, 1997, and May 8, 1997, to determine the water-producing zones, water-receiving zones, zones of vertical flow, borehole depth, and casing integrity in each well. This data and interpretation will be used to determine the location of the well intake for the existing open-hole wells, which will be retrofitted to isolate and monitor water-producing zones and prevent further cross-contamination within each open borehole, and identify wells that may need rehabilitation or replacement. Caliper and video logs were used to locate fractures, inflections on fluid-temperature and fluidresistivity logs indicated possible fluid-bearing fractures, and flowmeter measurements verified these locations. Single-point-resistance and natural-gamma logs provided information on stratigraphy. After interpretation of geophysical logs, video logs, and driller?s notes, all wells will be constructed so that water-level fluctuations can be monitored and discrete water samples collected from shallow, intermediate, and deep water-bearing zones in each well. Geophysical logs were run on seven bedrock and two deep bedrock wells. Gamma logs were run on 10 bedrock wells. Twenty-two wells were inspected visually with the borehole video camera for casing integrity.

Conger, Randall W.

1998-01-01

418

Multiple populations on the horizontal branch. I - Observations in the (log g, log T/eff/)-diagram  

NASA Technical Reports Server (NTRS)

Log T(eff) and log g have been determined for blue horizontal branch (HB) stars in the globular clusters M15, M3, M5, M92, and NGC 288 as a first step in determining the physical origin of gaps or bimodal distributions in the blue horizontal branches of a number of globular clusters. The (log g, log T/eff/) diagram for the 'normal' HB cluster M5 matches the standard theory quite well. The stars blueward of the gap in NGC 288 and the blue extension of the M3 HB have significantly lower gravity than predicted by the standard theory. The cooler stars in M3 agree well with the standard theory while those of NGC 2988 lie at slightly lower gravity. In M92, the sequence of stars is broadened toward the low gravity side more than expected either from standard evolution or from observational error. The data for M15 are too scattered to support firm conclusions but seem consistent with NGC 288.

Crocker, Deborah A.; Rood, Robert T.; O'Connell, Robert W.

1988-01-01

419

Materials, Safety, and Equipment Overview for Nanotechnology  

NSDL National Science Digital Library

Provided by the Nano4Me.org, the National Center for Nanotechnology Applications and Career Knowledge (NACK Center), this course features an overview of safety, equipment, and materials information regarding nanofabrication. It includes detailed lecture materials entitled Safety and Environmental Concerns; Vacuum Function, Operation and Systems; Materials Overview; General Processing Concerns, Contamination and Damage; and Basic Characterization Tools. Each separate PowerPoint contains in-depth coverage of each topic, including illustrations, examples, and comprehensive information. The website sponsoring this resource requires a quick, easy, free log-in to access this and many other great resources.

2010-03-08

420

About Personal Protective Equipment (PPE)  

MedlinePLUS

... and Gowns FDA's Role in Regulating PPE About Personal Protective Equipment (PPE) On this page: What is personal protective ... protective equipment with other users? Q. What is personal protective equipment? A. Personal protective equipment is any type of ...

421

Factor analysis of borehole logs for evaluating formation shaliness: a hydrogeophysical application for groundwater studies  

NASA Astrophysics Data System (ADS)

The calculation of groundwater reserves in shaly sand aquifers requires a reliable estimation of effective porosity and permeability; the amount of shaliness as a related quantity can be determined from well log analysis. The conventionally used linear model, connecting the natural gamma-ray index to shale content, often gives only a rough estimate of shale volume. A non-linear model is suggested, which is derived from the factor analysis of well-logging data. An earlier study of hydrocarbon wells revealed an empirical relationship between the factor scores and shale volume, independent of the well site. Borehole logs from three groundwater wells drilled in the northeastern Great Hungarian Plain are analyzed to derive depth logs of factor variables, which are then correlated with shale volumes given from the method of Larionov. Shale volume logs derived by the statistical procedure are in close agreement with those derived from Larionov's formula, which confirms the validity of the non-linear approximation. The statistical results are in good accordance with laboratory measurements made on core samples. Whereas conventional methods normally use a single well log as input, factor analysis processes all available logs to provide groundwater exploration with reliable estimations of shale volume.

Szabó, Norbert Péter; Dobróka, Mihály; Turai, Endre; Sz?cs, Péter

2014-05-01

422

New shielding protective equipment for live working  

Microsoft Academic Search

The new protective equipment forms a FARADAY cage, thus protecting the worker from unacceptably strong electrical fields as well as from being invaded by dangerous electric currents. The protective shielding clothing described is a personal protective equipment of the highest category. Therefore, it must be certified by an acknowledged examining and certifying authority. An application with regard to the attestation

Claudia Herzberg; Hartmut Rödel; Eberhard Engelmann

2001-01-01

423

Technology Equipment Rooms.  

ERIC Educational Resources Information Center

Examines telecommunications equipment room design features that allow for growth and can accommodate numerous equipment replacements and upgrades with minimal service disruption and with minimal cost. Considerations involving the central hub, power and lighting needs, air conditioning, and fire protection are discussed. (GR)

Day, C. William

2001-01-01

424

Equipment qualification maintenance  

Microsoft Academic Search

Over the past few years, the nuclear power industry has devoted a great deal of attention to achieving equipment qualification. As this goal approaches, the attention of prudent utilities is now being directed toward maintaining that qualification throughout the useful life of the equipment. This paper presents a Qualification Maintenance Program (QMP), which is designed to meet the Nuclear Regulatory

Scates

1982-01-01

425

AUDIOVISUAL EQUIPMENT STANDARDS.  

ERIC Educational Resources Information Center

RECOMMENDED STANDARDS FOR AUDIOVISUAL EQUIPMENT WERE PRESENTED SEPARATELY FOR GRADES KINDERGARTEN THROUGH SIX, AND FOR JUNIOR AND SENIOR HIGH SCHOOLS. THE ELEMENTARY SCHOOL EQUIPMENT CONSIDERED WAS THE FOLLOWING--CLASSROOM LIGHT CONTROL, MOTION PICTURE PROJECTOR WITH MOBILE STAND AND SPARE REELS, COMBINATION 2 INCH X 2 INCH SLIDE AND FILMSTRIP…

PATTERSON, PIERCE E.; AND OTHERS

426

Shipboard Electronic Equipments.  

ERIC Educational Resources Information Center

Fundamentals of major electronic equipments on board ships are presented in this text prepared for naval officers in general. Basic radio principles are discussed in connection with various types of transmitters, receivers, antennas, couplers, transfer panels, remote-control units, frequency standard equipments, teletypewriters, and facsimile…

Naval Personnel Program Support Activity, Washington, DC.

427

Equipment & New Products.  

ERIC Educational Resources Information Center

Presents several new products and equipment for teaching college science courses such as laser optics bench, portable digital thermometer, solar energy furnaces and blackboard optics kit. A description of all equipment or products, cost, and addresses of manufacturers are also included. (HM)

Poitras, Adrian W., Ed.

1977-01-01

428

Recognizing Patterns In Log-Polar Coordinates  

NASA Technical Reports Server (NTRS)

Log-Hough transform is basis of improved method for recognition of patterns - particularly, straight lines - in noisy images. Takes advantage of rotational and scale invariance of mapping from Cartesian to log-polar coordinates, and offers economy of representation and computation. Unification of iconic and Hough domains simplifies computations in recognition and eliminates erroneous quantization of slopes attributable to finite spacing of Cartesian coordinate grid of classical Hough transform. Equally efficient recognizing curves. Log-Hough transform more amenable to massively parallel computing architectures than traditional Cartesian Hough transform. "In-place" nature makes it possible to apply local pixel-neighborhood processing.

Weiman, Carl F. R.

1992-01-01

429

Nonblocking and orphan free message logging protocols  

NASA Technical Reports Server (NTRS)

Currently existing message logging protocols demonstrate a classic pessimistic vs. optimistic tradeoff. We show that the optimistic-pessimistic tradeoff is not inherent to the problem of message logging. We construct a message-logging protocol that has the positive features of both optimistic and pessimistic protocol: our protocol prevents orphans and allows simple failure recovery; however, it requires no blocking in failure-free runs. Furthermore, this protocol does not introduce any additional message overhead as compared to one implemented for a system in which messages may be lost but processes do not crash.

Alvisi, Lorenzo; Hoppe, Bruce; Marzullo, Keith

1992-01-01

430

Evaluation of geophysical logs, Phase I, at Willow Grove Naval Air Station, Montgomery County, Pennsylvania  

USGS Publications Warehouse

Between April and June 1997, the U.S. Navy contracted Brown and Root Environmental, Inc., to drill 20 monitor wells at the Willow Grove Naval Air Station in Horsham Township, Montgomery County, Pa. The wells were installed to monitor water levels and allow collection of water samples from shallow, intermediate, and deep water-bearing zones. Analysis of the samples will determine the horizontal and vertical distribution of any contaminated ground water migrating from known contaminant sources. Eight wells were drilled near the Fire Training Area (Site 5), five wells near the 9th Street Landfill (Site 3), four wells at the Antenna Field Landfill (Site 2), and three wells near Privet Road Compound (Site 1). Depths range from 73 to 167 feet below land surface. The U.S. Geological Survey conducted borehole-geophysical and borehole-video logging to identify water-bearing zones so that appropriate intervals could be screened in each monitor well. Geophysical logs were run on the 20 monitor wells and 1 existing well. Video logs were run on 16 wells. Caliper and video logs were used to locate fractures, inflections on fluid-temperature and fluid-resistivity logs were used to locate possible water-bearing fractures, and flowmeter measurements verified these locations. Single-point-resistance and natural-gamma logs provided information on stratigraphy. After interpretation of geophysical logs, video logs, and driller's notes, all wells were screened such that water-level fluctuations could be monitored and discrete water samples collected from one or more shallow and intermediate water-bearing zones in each borehole.

Conger, R. W.

1997-01-01