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1

Well Logs  

NSDL National Science Digital Library

This activity provides students with three fundamental borehole geophysics experiences using real data -- correlating, mapping, and logging. Students are asked to correlate well logs and construct maps and cross-sections based on that information. Students are also asked to construct a "mud log" from actual drill cuttings and compare their interpretation to that from a borehole geophysics log. This activity as minimal/no quantitative component.

Brewer, Kevin

2

Injection Well Logging Using Viscous EOR Fluids  

Microsoft Academic Search

A new tool has been developed that overcomes problems associated with logging injection wells in the presence of viscous fluids. The tool was evaluated in the laboratory and the field in water and polymer injection wells. Results indicate that the tool provides better information than conventional equipment. Special attention to log interpretation is required in zones where the flow pattern

Bruce Knight; Mohammad Davarzani

1986-01-01

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

An integrated digital well logging system  

SciTech Connect

Basics of the SLAM Digital Combination Logging System are discussed including an overview which describes each of its major components; the computerbased surface data acquisition system, wellsite analysis software package, and the individual and combination measurement systems used with SLAM. Combination logging runs that are possible with the SLAM system are presented to illustrate their application in a number of different geologic and borehole conditions. The advantages to performing combination logging runs are also discussed. Log presentations available are illustrated to demonstrate methods for displaying combination log data in usable formats. Diagnostic programs and troubleshooting aids are reviewed to demonstrate their ability to help predict when equipment is becoming marginal, and to minimize lost time due to equipment failure. Standard methods for performing instrument calibrations are described, including techniques to perform master calibrations at the shop or wellsite, as well as before and after wellsite checks performed with instruments suspended over the borehole, or on the catwalk.

Peressini, B.; Fertl, W.H.; Howells, A.P.S.

1982-09-01

5

Using Well Logs in the Petroleum Industry  

NSDL National Science Digital Library

This exercise shows how well logs are used in the petroleum industry. It is designed as a first exposure to well logs for undergraduate geology majors and introduces not only well logs and their interpretation as proxies for stratigraphic sections, but also investigates concepts of porosity and permeability, oil reservoirs, and structural traps.

Borowski, Walter

6

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

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

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

9

Selecting Aquifer Wells for Planned Gyroscopic Logging  

SciTech Connect

Understanding the configuration of the eastern Snake River Plain aquifer's water table is made difficult, in part, due to borehole deviation in aquifer wells. A borehole has deviation if it is not vertical or straight. Deviation impairs the analysis of water table elevation measurements because it results in measurements that are greater than the true distance from the top of the well to the water table. Conceptual models of the water table configuration are important to environmental management decision-making at the INEEL; these models are based on measurements of depth to the water table taken from aquifer wells at or near the INEEL. When accurate data on the amount of deviation in any given borehole is acquired, then measurements of depth-to-water can be adjusted to reflect the true depth so more accurate conceptual models can be developed. Collection of additional borehole deviation data with gyroscopic logging is planned for selected wells to further our confidence in the quality of water level measurements. Selection of wells for the planned logging is based on qualitative and quantitative screening criteria. An existing data set from magnetic deviation logs was useful in establishing these criteria however, are considered less accurate than gyroscopic deviation logs under certain conditions. Population distributions for 128 aquifer wells with magnetic deviation data were used to establish three quantitative screening thresholds. Qualitative criteria consisted of administrative controls, accessibility issues, and drilling methods. Qualitative criteria eliminated all but 116 of the 337 aquifer wells, in the vicinity of the INEEL, that were initially examined in this screening effort. Of these, 72 have associated magnetic deviation data; 44 do not. Twenty-five (25) of the 72 wells with magnetic deviation data have deviation greater than one of the three quantitative screening thresholds. These 25 are recommended for the planned gyroscopic borehole deviation surveying. Nineteen (19) of the 44 wells without magnetic deviation data were selected for the planned gyroscopic logging based on their location relative to facilities, site boundaries, and contaminant transport concerns. In total, 44 aquifer wells (25 with magnetic deviation data and 19 without) are recommended for planned gyroscopic logging.

Rohe, Michael James; Studley, Gregory Wayne

2002-04-01

10

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.

11

Gain stabilization for radioactivity well logging apparatus  

SciTech Connect

A new and improved gain stabilization system for radioactivity well logging apparatus is of the type having a scintillation crystal and optically coupled photomultiplier in a sonde to detect radiation in the borehole and formation elements in response to neutron bombardment. The gain stabilization system includes a light emitting diode driven by a pulser and furnishing scintillations to the photomultiplier, resulting in a stabilization pulse which is furnished to electronic circuitry at the surface for stabilization purposes.

Whatley, H.A.

1980-09-02

12

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

13

21 CFR 211.182 - Equipment cleaning and use log.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records and Reports § 211.182 Equipment cleaning and use log. A written record of major...

2011-04-01

14

21 CFR 211.182 - Equipment cleaning and use log.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records and Reports § 211.182 Equipment cleaning and use log. A written record of major...

2010-04-01

15

Comprehensive study of LASL Well C/T-2 Roosevelt Hot Springs KGRA, Utah, and applications to geothermal well logging  

SciTech Connect

Utah State Geothermal Well 9-1 in the Roosevelt Hot Springs KGRA, Beaver County, Utah, has been donated by Phillips Petroleum Company for calibration and testing of well-logging equipment in the hot, corrosive, geothermal environment. It is the second Calibration/Test Well (C/T-2) in the Geothermal Log Interpretation Program. A study of cuttings and well logs from Well C/T-2 was completed. This synthesis and data presentation contains most of the subsurface geologic information needed to effect the total evaluation of geophysical logs acquired in this geothermal calibration/test well, C/T-2.

Glenn, W.E.; Hulen, J.B.; Nielson, D.L.

1981-02-01

16

Knowledge-based stratigraphic well-log correlation  

E-print Network

-base. The front-end-processor abstracts symbols from digitized well-log data, identifies lithologic zones, and attaches attributes to the lithologic zones. The correlation process uses the higher level information that is abstracted from the well-log data...-base. The front-end-processor abstracts symbols from digitized well-log data, identifies lithologic zones, and attaches attributes to the lithologic zones. The correlation process uses the higher level information that is abstracted from the well-log data...

Denton, Michael A.

2012-06-07

17

Fluid-Temperature Logs for Selected Wells in Eastern Washington.  

National Technical Information Service (NTIS)

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...

K. L. Stoffel, S. Widness

1983-01-01

18

Automatic well log correlation using neural networks  

E-print Network

is an iterative procedure for finding weights that minimize some error function. The most powerful leazning algorithm developed today (which is used in this project) is the error-back-propagation (EBP) algorithm sometimes referred to as the Generalized... training log). The total error (ET) is calculated in every pass. When the total error reaches an acceptable level, training halts. The error at every node is used to adjust network weights as described in the EBP algorithm. Weight adjustments should...

Habiballah, Walid Abdulrahim

2012-06-07

19

Requirements for downhole equipment used for geothermal-well stimulation. Geothermal-reservoir well-stimulation program  

SciTech Connect

The needs for new and improved down-hole stimulation equipment for geothermal wells are identified. The following kinds of equipment are discussed: mechanical downhole recording instruments, electric line logging tools, and downhole tools used for zone isolation.

Not Available

1982-08-01

20

Interpretation of geophysical well logs in permafrost. Final report  

SciTech Connect

This report is a collection of information on the interpretation of well logs and borehole geophysical surveys in permafrost. The body of the report is preceded by an executive summary that gives the highlights of the report in condensed form. The introductory chapter contains background information that is fundamental to the understanding of well log applications in permafrost, including definitions and descriptions of well logs, permafrost, and related terms, and illustrations showing the extent of permafrost in Alaska. Chapter 2 presents information on physical properties of permafrost that relate to well log interpretation, including porosity and pore-filling media (water, ice and air), and their effects on thermal properties, electrical properties and acoustic properties. Chapters 3-8 describe the following types of well logs in detail, including measurement principles and methods, procedures for calibration and interpretation, and identification of special problems relatd to permafrost: thermal logs, electric logs, sonic logs, nuclear logs, magnetic logs, and miscellaneous (caliper and drilling) logs. Chapter 9 gives information on three types of borehole geophysical surveys, electrical resistivity, seismic velocity, and borehole gravity, with emphasis on the increased depth of investigation afforded by these surveys as compared with well logs. Chapter 10 describes a number of specific applications. A concluding chapter summariezes the information contained in the body of the report and includes a table that gives an overview of the relative value of various borehole geophysical measurements that can be used for delineating and characterizing permafrost. Conclusions of the report are that a number of standard borehole measurement techniques have been tried and proven in permafrost and can be used effectively to delineate and characterize earth material penetrated by the borehole. 19 figs., 8 tabs.

Scott, J.H.; Petersen, J.K.; Osterkamp, T.E.; Kawasaki, K.

1986-01-01

21

Thermal conductivity from core and well log data  

Microsoft Academic Search

A number of attempts have been made to determine thermal conductivity from well log data, including direct empirical relationships between measured properties and more complex models based on mixing laws. The latter require interpretation of well log data in terms of lithology and porosity prior to thermal conductivity estimation. While the second approach is more universally applicable there is general

A. Hartmann; V. Rath; C. Clauser

2003-01-01

22

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

Code of Federal Regulations, 2011 CFR

...false 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,...

2011-07-01

23

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

Code of Federal Regulations, 2010 CFR

...false 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,...

2010-07-01

24

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

Code of Federal Regulations, 2012 CFR

...false 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,...

2012-07-01

25

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

...false 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,...

2014-07-01

26

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

27

Find Funds for Wellness Assessment Equipment.  

ERIC Educational Resources Information Center

Many physical education teachers have difficulty finding ways to purchase wellness assessment equipment. The article provides strategies to help them find the money for needed equipment, highlighting the physical education budget, the computer equipment budget, grants, local businesses, statewide organizations, universities, and national…

Buck, Marilyn M.; Kirkpatrick, Beth

1995-01-01

28

Geophysical well logging operations and log analysis in Geothermal Well Desert Peak No. B-23-1  

SciTech Connect

Geothermal Well Desert Peak No. B-23-1 was logged by Dresser Atlas during April/May 1979 to a total depth of 2939 m (9642 ft). A temperature of 209/sup 0/C (408/sup 0/F) was observed on the maximum thermometer run with one of the logging tools. Borehole tools rated to a maximum temperature of 204.4/sup 0/C (400/sup 0/F) were utilized for logging except for the Densilog tool, which was from the other set of borehole instruments, rated to a still higher temperature, i.e., 260/sup 0/C (500/sup 0/F). The quality of the logs recorded and the environmental effects on the log response have been considered. The log response in the unusual lithologies of igneous and metamorphic formations encountered in this well could be correlated with the drill cutting data. An empirical, statistical log interpretation approach has made it possible to obtain meaningful information on the rocks penetrated. Various crossplots/histograms of the corrected log data have been generated on the computer. These are found to provide good resolution between the lithological units in the rock sequence. The crossplotting techniques and the statistical approach were combined with the drill cutting descriptions in order to arrive at the lithological characteristics. The results of log analysis and recommendations for logging of future wells have been included.

Sethi, D.K.; Fertl, W.H.

1980-03-01

29

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

30

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

31

Geophysical logs of selected wells in Eastern Washington  

SciTech Connect

This report consists of geophysical well logs compiled during studies of the geohydrology and low temperature geothermal resources of eastern Washington. The geophysical logs are divided into two groups. Part A consists of wells concentrated in the Moses Lake-Ritzville-Connell area. Results of the geohydrologic study are discussed in Widness (1983, 1984). Part B consists of wells outside of the Moses Lake-Ritzville-Connell study area.

Stoffel, K.L.; Widness, S.

1983-12-01

32

Application of gas-filled detectors for well logging  

NASA Astrophysics Data System (ADS)

The advantages of using gas-filled multiwire proportional chambers (MWPC) for well logging are discussed. In particular, applicability of the MWPC in casing quality control and cement bond logging is described. It is shown that spatial distribution measurement of scattered gamma rays can provide information about the material and presence of the defects. The results of computations performed with GEANT4 are in the reasonable agreement with the experimental data.

Korkin, R.; Baru, S. E.; Porosev, V. V.; Savinov, G. A.

2008-06-01

33

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

34

Thermal conductivity from core and well log data  

NASA Astrophysics Data System (ADS)

A number of attempts have been made to determine thermal conductivity from well log data, including direct empirical relationships between measured properties and more complex models based on mixing laws. The latter require interpretation of well log data in terms of lithology and porosity prior to thermal conductivity estimation. While the second approach is more universally applicable there is general agreement that every geologic setting needs calibration of well log data with core measurements. We present data and interpretations from the German Western Molasse Basin, an Alpine foreland basin. Cores were obtained from a geothermal well nearly continuously at depths from 550 - 800 m. The drilled sequence consists of typical Molasse sediments: sand- to siltstones with various amounts of calcareous components and clays. Especially clay makes the acquisition and interpretation of measurements a challenging task. A total of 170 samples was taken from the borehole. We measured thermal conductivity, sonic velocity, and bulk density in the laboratory on dry and saturated samples. A number of logs were obtained in the same borehole. We use these two data sets to review the relationships between the laboratory and field measurements for different models. Additionally, heat capacity was measured on selected samples. Using the heat capacity and density we calculate a thermal diffusivity log. This parameter and its variability is important for transient heat diffusion problems.

Hartmann, A.; Rath, V.; Clauser, C.

2003-04-01

35

Application of the spread-spectrum technique in well logging  

SciTech Connect

This paper presents the novel concept of employing the noise insensitive spread-spectrum technique in well logging. The proposed design of a spread-spectrum device improves the performance of well logging tools, particularly within highly noisy environments. The heart of the device is a shift register which generates a pseudorandom binary code sequence. A coder is connected to the transmitter and codes the probing signal by utilizing the pseudorandom sequence. A decoder is connected to the receiver and correlates the return signal to the same sequence, which is used as a sliding reference. Shifts as small as a fraction of a bit are unambiguously resolvable, and distance resolution of the order of micrometers is achievable. Spread-spectrum well logging tools can operate even with coded signal-to-noise ratio below zero-dB. The spread-spectrum device can be interfaced with any available wave transmitting logging tool. However, tools employing acoustic waves are favorable because the acoustic wave propagation velocity is low and allows the use of inexpensive electronics. The problems associated with high temperatures which are commonly encountered In geothermal reservoirs are bypassed, since the spread-spectrum device can be located either inside the well logging tool or together with the supporting electronics on the surface.

Chrysikopoulos, Constantinos V.; Dadakarides, Simos D.

1988-01-01

36

Electronic neutron sources for compensated porosity well logging  

NASA Astrophysics Data System (ADS)

The viability of replacing Americium-Beryllium (Am-Be) radiological neutron sources in compensated porosity nuclear well logging tools with D-T or D-D accelerator-driven neutron sources is explored. The analysis consisted of developing a model for a typical well-logging borehole configuration and computing the helium-3 detector response to varying formation porosities using three different neutron sources (Am-Be, D-D, and D-T). The results indicate that, when normalized to the same source intensity, the use of a D-D neutron source has greater sensitivity for measuring the formation porosity than either an Am-Be or D-T source. The results of the study provide operational requirements that enable compensated porosity well logging with a compact, low power D-D neutron generator, which the current state-of-the-art indicates is technically achievable.

Chen, A. X.; Antolak, A. J.; Leung, K.-N.

2012-08-01

37

An expert system advisor for well log quality control  

E-print Network

, in identical formats for quality control of the sonic, gamma ray and dual induction well logs. A ~ial system program shell served as the fork for building the ~ system. The system has been written as a prototype model. With minimal alterations... PORTION OF THE WELL IOG QUALZIY CONTROL ~ SYSZEM ADVISOR APPENDIX C ? ~TION OF TAXONCMIES 59 59 62 TABLE OF CONTENTS (cont. ) DUAL INDUCTION IOG Page 64 APPENDIX D ? ~CE TREES FOR THE GAK% RAY, DUAL INDUCTION AND SONIC IOGS 68 GAMMA RAY LOG...

Warnken, Dean Kennedy

2012-06-07

38

Drilling, logging and preliminary well testing of geothermal well Susan 1, Susanville, Lassen County, California  

SciTech Connect

Susan 1, a hot water production well, was drilled late in 1980 for the City of Susanville, California, as part of its geothermal space-heating project. A history of drilling, logging, completion and pump testing of this well is presented. Susan 1 was drilled to 930 feet using local river water with a 17-1/2-inch bit from 50 to 540 feet and a 12-1/2-inch bit from 540 to 927 feet. A 12-3/4-inch solid casing was set from surface to 350 feet, a slotted casing from 350 to 538 feet, and a 8-5/8-inch slotted casing from 520 to 925 feet. Interpretations of the following logs and test data from this well are presented: drilling logs (penetration rate, water loss and gain, return temperatures); formation logs (description of well cuttings, caliper, spontaneous potential, electrical resistivity, gamma ray, neutron); production logs (temperature, spinner); and pump test data.

McNitt, J.R.; Petersen, C.A.; Sanyal, S.K.

1981-03-01

39

Application of Nuclear Well Logging Techniques to Lunar Resource Assessment  

NASA Technical Reports Server (NTRS)

The use of neutron and gamma ray measurements for the analysis of material composition has become well established in the last 40 years. Schlumberger has pioneered the use of this technology for logging wells drilled to produce oil and gas, and for this purpose has developed neutron generators that allow measurements to be made in deep (5000 m) boreholes under adverse conditions. We also make ruggedized neutron and gamma ray detector packages that can be used to make reliable measurements on the drill collar of a rotating drill string while the well is being drilled, where the conditions are severe. Modern nuclear methods used in logging measure rock formation parameters like bulk density and porosity, fluid composition, and element abundances by weight including hydrogen concentration. The measurements are made with high precision and accuracy. These devices (well logging sondes) share many of the design criteria required for remote sensing in space; they must be small, light, rugged, and able to perform reliably under adverse conditions. We see a role for the adaptation of this technology to lunar or planetary resource assessment missions.

Albats, P.; Groves, J.; Schweitzer, J.; Tombrello, T.

1992-01-01

40

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

41

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

42

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

43

Interpretation of well log response in the Austin chalk  

E-print Network

-m The intermediate resistivities are the re ult of water re-entering the pores following hydrocarbon migration. Fractures were identified from standard logs by comparing porosity log responses with the gamma-ray, caliper and resistivity logs. An increase... in density and neutron porosities relative to sonic transit time indicate the presence of secondary porosity due to fracturing. Comparison with the gamma-ray log helps to distinguish secondary porosity from an increase in total porosity due to increased...

Hinds, Gregory Scott

2012-06-07

44

Porosity and pore structure from acoustic well logging data  

SciTech Connect

Wyllie's time-average equation and subsequent refinements have been used for over 20 years to estimate the porosity of reservoir rocks from compressional (P)-wave velocity (or its reciprocal, transit time) recorded on a sonic log. This model, while simple, needs to be more convincingly explained in theory and improved in practice, particularly by making use of shear, (S)-wave velocity. One of the most important factors affecting elastic velocities in a rock is pore structure, which is also a controlling factor for transport properties of a rock. Now that S-wave information can be obtained from the sonic log, it may be used with P-waves to provide a better understanding of pore structure. A new acoustic velocities-to-porosity transform based on an elastic velocity model developed by Kuster and Toksoez is proposed. Employing an approximation to an equivalent pore aspect ratio spectrum, pore structure for reservoir rocks is taken into account, in addition to total pore volume. Equidimensional pores are approximated by spheres and rounded spheroids, while grain boundary pores and flat pores are approximated by low aspect ratio cracks. An equivalent pore aspect ratio spectrum is characterized by a power function which is determined by compressional- and shear-wave velocities, as well as by matrix and inclusion properties. As a result of this more sophisticated elastic model of porous rocks and a stricter theory of elastic wave propagation, the new method leads to a more satisfactory interpretation and fuller use of seismic and sonic log data. Calculations using the new transform on data for sedimentary rocks, obtained from published literature and laboratory measurements, are presented and compared at atmospheric pressure with those estimated from the time-average equation. Results demonstrate that the new method provides more detailed information on pore volume and pore structure of reservoir rocks.

Tao, G.; King, M.S. (Imperial Coll. of Science, Technology and Medicine, London (United Kingdom))

1993-05-01

45

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

46

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

47

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

48

Calculation of sensitivity coefficients for a neutron well logging tool  

E-print Network

in this research. TWODANT, a, two-dimensional computer code was used to estimate the neutron flux and other neutronic information concerning the logging tool's response, then a straightforward direct method based on the definition of sensitivity wss used..., and acoustic techniques. Neutron logging is one of the newer methods based on nuclear radiation and it has been increasingly applied over the last fifteen years using both steady ? state and pulsed neutron sources of various types. (Hearst et al. , 1985...

Chen, Chien-Hsiang

2012-06-07

49

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

50

Case history on geothermal-well-log interpretation: Surprise Valley, California  

SciTech Connect

Well logs from a 1972 geothermal well drilled in California's Surprise Valley are discussed. The well is in an igneous formation, primarily basalt in the logged interval, and had a bottom-hole temperature of about 170/sup 0/C at a total depth exceeding 1400 m. It produced good flow rates from what is presumably a formation with predominately fracture-related permeability. The well has special interest because fractures could be located approximately by the appearance of well-defined secondary crystallization in the drill cuttings. The original use of the log data in evaluating the well when it was drilled is discussed. In addition, the log data are reviewed and valuable data are obtained on log response in basalts, the effects of secondary mineralization, fracture detection, and aspects of the resistivity logs. The Surprise Valley well gives a clear demonstration of the value of thorough logging in geothermal exploratory wells, especially in the identification and location of potential production zones.

Rigby, F.A.; Zebal, G.P.

1981-06-01

51

Determination of true static formation temperature from well logs  

SciTech Connect

Several concepts that attempt to determine static (true) formation temperature from log-derived BHT measurements with and without knowledge of drilling fluid circulation time have been reviewed. Whereas several refined models are available, the simple Horner-type technique provides quick and reliable static (true) formation temperature estimates.

Fertl, W.H.; Chilingarian, G.V.; Yen, T.F.

1986-01-01

52

GEOLOGICAL APPLICATIONS OF WELL LOGS: AN INTRODUCTORY BIBLIOGRAPHY AND SURVEY OF THE WELL LOGGING LITERATURE THROUGH SEPTEMBER 1986 ARRANGED BY SUBJECT.  

USGS Publications Warehouse

This report includes over 1,350 individual citations as well as a first-author index. The purpose of this bibliography is twofold, 1) to provide a basic, first-stop resource on well logging which the non-specialist, i. e. , geoscientist, can consult and, 2) to provide a reference on geologic applications for the non-geoscientist, i. e. , log analyst or petroleum engineer, as well as for the geoscientist.

Prensky, Stephen E.

1987-01-01

53

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

54

GEOLOGICAL APPLICATIONS OF WELL LOGS. AN INTRODUCTORY BIBLIOGRAPHY AND SURVEY OF THE WELL LOGGING LITERATURE, ARRANGED BY SUBJECT, UPDATE, OCTOBER 1986 THROUGH OCTOBER 1987.  

USGS Publications Warehouse

This update includes new publications for the period October 1986-October 1987 as well as earlier publications of interest that were omitted from the original due either to oversight or because they had not been received in sufficient time for inclusion. Part A covers basic well logging. Part B covers geological applications.

Prensky, Stephen E.

1987-01-01

55

40 CFR 146.66 - Logging, sampling, and testing prior to new well operation.  

...testing prior to new well operation. (a) During the drilling and construction of a new Class I hazardous waste injection well, appropriate logs and tests shall be run to determine or verify the depth, thickness, porosity,...

2014-07-01

56

40 CFR 146.66 - Logging, sampling, and testing prior to new well operation.  

Code of Federal Regulations, 2013 CFR

...testing prior to new well operation. (a) During the drilling and construction of a new Class I hazardous waste injection well, appropriate logs and tests shall be run to determine or verify the depth, thickness, porosity,...

2013-07-01

57

40 CFR 146.66 - Logging, sampling, and testing prior to new well operation.  

Code of Federal Regulations, 2012 CFR

...testing prior to new well operation. (a) During the drilling and construction of a new Class I hazardous waste injection well, appropriate logs and tests shall be run to determine or verify the depth, thickness, porosity,...

2012-07-01

58

Flowing fluid electric conductivity logging for a deep artesian well in fractured rock with regional flow  

NASA Astrophysics Data System (ADS)

SummaryThe flowing fluid electric conductivity (FFEC) logging method is a well-logging technique that may be used to estimate flow rate, salinity, transmissivity, and hydraulic head of individual fractures or high-permeability zones intersected by a wellbore. Wellbore fluid is first replaced with fluid of a contrasting electric conductivity, then repeated FEC logging is done while the well is pumped. Zones where fluid flows into the wellbore show peaks in the FEC logs, which may be analyzed to infer inflow rate and salinity of the individual fractures. Conducting the procedure with two or more pumping rates (multi-rate FFEC logging) enables individual fracture transmissivity and hydraulic head to be determined. Here we describe the first application of the multi-rate FFEC logging method to an artesian well, using a 500-m well in fractured rock at Horonobe, Japan. An additional new factor at the site is the presence of regional groundwater flow, which heretofore has only been studied with synthetic data. FFEC logging was conducted for two different pumping rates. Several analysis techniques had to be adapted to account for the artesian nature of the well. The results were subsequently compared with independent salinity measurements and transmissivity and hydraulic head values obtained from packer tests in the same well. Despite non-ideal operating conditions, multi-rate FFEC logging successfully determined flow rate, salinity, and transmissivity of 17 conducting fractures intercepted by the logged section of the borehole, including two fractures with regional groundwater flow. Predictions of hydraulic head were less accurate, a not unexpected result in light of operational problems and the form of the equation for hydraulic head, which involves the difference between two uncertain quantities. This study illustrates the strengths and weaknesses of the multi-rate FFEC logging method applied to artesian wells. In conjunction with previous studies, it demonstrates the usefulness of the method for a broad range of conditions encountered in subsurface fractured rock.

Doughty, Christine; Tsang, Chin-Fu; Yabuuchi, Satoshi; Kunimaru, Takanori

2013-03-01

59

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

60

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

SciTech Connect

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 in four production wells (ZCQ-3, ZCQ-4, ZCQ-5, and ZCQ-6). The teams took measurements of the wells in both static (shut-in) and flowing conditions, using the high-temperature well logging tools developed at Los Alamos National Laboratory. Two well logging missions were conducted in the Zunil field. In October 1988 measurements were made in well ZCQ-3, ZCQ-5, and ZCQ-6. In December 1989 the second field operation logged ZCQ-4 and repeated logs in ZCQ-3. Both field operations included not only well logging but the collecting of numerous fluid samples from both thermal and nonthermal waters. 18 refs., 22 figs., 7 tabs.

Adams, A.; Dennis, B.; Van Eeckhout, E.; Goff, F.; Lawton, R.; Trujillo, P.E.; Counce, D.; Archuleta, J. (Los Alamos National Lab., NM (USA)); Medina, V. (Instituto Nacional de Electrificacion, Guatemala City (Guatemala). Unidad de Desarollo Geotermico)

1991-07-01

61

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

62

High-energy photon transport modeling for oil-well logging  

E-print Network

Nuclear oil well logging tools utilizing radioisotope sources of photons are used ubiquitously in oilfields throughout the world. Because of safety and security concerns, there is renewed interest in shifting to ...

Johnson, Erik D., Ph. D. Massachusetts Institute of Technology

2009-01-01

63

40 CFR 146.87 - Logging, sampling, and testing prior to injection well operation.  

Code of Federal Regulations, 2011 CFR

...logs, surveys and tests to determine or verify the depth, thickness, porosity, permeability, and lithology of, and the salinity of any formation fluids in all relevant geologic formations to ensure conformance with the injection well...

2011-07-01

64

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

65

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

66

Visualization of nuclear particle trajectories in nuclear oil-well logging  

Microsoft Academic Search

Nuclear oil-well logging measures specific properties of subsurface geological formations as a function of depth in the well. The knowledge gained is used to evaluate the hydrocarbon potential of the surrounding oil field. The measurements are made by lowering an instrument package into an oil well and slowly extracting it at a constant speed. During the extraction phase, neutrons or

C. R. Case; J. M. Chiaramonte

1991-01-01

67

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

68

Characterization of light hydrocarbon reservoirs by gradient-NMR well logging.  

PubMed

New methods for acquiring and processing gradient NMR well log data enable signals from gas, light oil, and water to be unambiguously separated and, in many cases, quantified. These methods exploit the combined effects of T1-based and diffusion-based contrast on log response. T1 contrast, which separates the water and light hydrocarbon (oil or gas) signals, is measured by subtracting spin-echo decays measured at different, appropriately chosen wait times. Gas and oil signals are then separated based on the large contrast in the diffusion-induced T2 relaxation times for gas vs. liquid. Practical application of these principles is illustrated with new log examples that also highlight the advantages of NMR over traditional logging methods for detecting and typing light hydrocarbons, especially in mineralogically complex rocks. PMID:8970080

Mardon, D; Prammer, M G; Coates, G R

1996-01-01

69

Reservoir characterization from well-logs data using neural network models  

NASA Astrophysics Data System (ADS)

The first part of this work consists to use the three neural network models in a supervised learning to estimate petrophysical parameters from well-logs data. Parameters to be estimated are: Porosity, Permeability and Water saturation. The neural network machines used consist of the Multilayer perceptron (MLP), the Radial Basis Function (RBF) and Hopfield model (HPF). The main input used to train these neural models is the raw well-logs data recorded in a borehole located in the Algerian Sahara. A comparison between the three neural machines shows that the MLP is the most suitable for petrophysical parameters prediction. The second part consists to combine between the Self-Organizing Map (SOM) neural network model and the MLP for lithofacies classification from well-logs data. Firstly, the self organizing map is trained in an unsupervised learning; the input is the raw well-logs data. The SOM will give in the output, a set of classes of lithology. After that the core rocks data are used for the map indexation. The set of lithology classes are generalized for the full depth interval, including depths where core rock analysis doesn't exist. This last will be used as an input to train an MLP model. Obtained results show that the coupled neural network models can give a more precise classification than the SOM or the MLP. Keywords: Well-logs data, MLP, SOM, RBF, HPF, Supervised, Unsupervised.

Aliouane, L.; Ouadfeul, S.; Djarfour, N.; Boudella, A.

2012-04-01

70

Fractal characteristics analysis of logging facies using multi-well data  

NASA Astrophysics Data System (ADS)

The long-term exploration and development practice shows that the main problem of oil gas exploration and development to face is the skills of prediction and description for reservoir, it is mainly because the control factors of horizontal distribution of reservoir and physical properties development are very complex, which causes the a large variety in horizontal distribution of reservoir, and the low yield of individual well and so on. So far, all kinds of prediction skills are based on linearity assumption, with a low resolution and accuracy for reservoir prediction and description, it also has a low successful rate of detailed description for complex structure of reservoir and sharp physical properties change. It is a direct and efficient way to use multi-well well logging data to research on a detailed geology of reservoir so that ensure a steady yield of oil field and raise the recovery ratio. Through analyzing the fractal dimensions of 39 wells of log facies, extracting the varying characteristics of a log presentation, which including of the characteristics of amplitude and pattern, and other interpretation conclusions (such as sedimentary structure, paleocurrent direction etc), classifies the stratigraphic cross-sections as the finite log facies, uses core analysis and other geological data to predict the underground structural characteristics of reservoir, it can discover the rise and fall of log facies's fractal dimensions caused by the sharp difference of geological structure of different wells, and the clear corresponding relationship between them.

ZhanJie, F.; Meng, X.

2011-12-01

71

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

72

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...

73

Well-logging probe for measuring tritium: construction and operating manual  

SciTech Connect

This document describes the as-built construction and operating procedures for a well-logging instrument capable of measuring tritium in situ in a well or borehole as small as 3-inch schedule 40 pipe. A companion document, A Design Manual for a Well-Logging Probe Capable of Measuring Tritium, PNL-4069, should be referred to for all design information and drawings. This document contains sections describing changes made between the design and construction phases, the general configuration of the instrument, and step-by-step operating procedures. The instrument can sample air or water and can purify the sample from other radionuclides or chemical contaminants. The instrument will operate satisfactorily in the presence of a moderate gamma-ray background and can measure tritium concentrations as low as 50 pCi/ml of water in normal logging operations.

Menninga, C.; Brodzinski, R.L.

1983-04-01

74

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

75

Performance evaluation of active wireline heave compensation systems in marine well logging environments  

NASA Astrophysics Data System (ADS)

The basic functionality and performance of a new Schlumberger active wireline heave compensation system on the JOIDES Resolution was evaluated during the sea trial and a 3-year period of the IODP Phase II operations. A suite of software programs was developed to enable real-time monitoring of the dynamics of logging tools, and assess the efficiency of wireline heave compensation during downhole operations. The evaluation of the system effectiveness was performed under normal logging conditions as well as during stationary tests. Logging data were analyzed for their overall quality and repeatability, and to assess the reliability of high-resolution data such as formation microscanner (FMS) electrical images. This revealed that the system reduces 65-80 % of displacement or 88-98 % variance of downhole tool motion in stationary mode under heave conditions of ±0.2-1.5 m and water depths of 300-4,500 m in open holes. Under similar water/heave conditions, the compensator system reduces tool displacement by 50-60 %, or 75-84 % variance in downhole tool motion during normal logging operations. Such compensation efficiency (CE) is comparable to previous compensation systems, but using advanced and upgradeable technologies, and provides 50-85 % heave motion and heave variance attenuation. Moreover, logging down/up at low speeds (300-600 m/h) reduces the system's CE values by 15-20 %, and logging down at higher speeds (1,000-1,200 m/h) eliminates CE values by 55-65 %. Considering the high quality of the logging data collected, it is concluded that the new system can provide an improved level of compensation over previous systems. Also, if practically feasible, future integration of downhole cable dynamics as an input feedback into the current system could further improve its compensation efficiency during logging operations.

Liu, Tanzhuo; Iturrino, Gerardo; Goldberg, David; Meissner, Eric; Swain, Kerry; Furman, Clayton; Fitzgerald, Peter; Frisbee, Nathan; Chlimoun, Joe; Van Hyfte, John; Beyer, Ron

2013-02-01

76

Preliminary Analysis of the Downhole Well Logs from the Gulf of Mexico Gas Hydrate JIP Cruise  

NASA Astrophysics Data System (ADS)

The downhole logging while drilling (LWD) and conventional wireline (CWL) logging operations on the Gulf of Mexico Gas Hydrate JIP Cruise were designed in part to obtain data needed to assess the occurrence and concentration of gas hydrates at several key sites within the Gulf of Mexico. LWD and CWL operations were conducted in two different offshore lease areas, Atwater Valley 13/14 and Keathley Canyon 151, in water depths ranging from 1280 to 1330 m. LWD tools measure in-situ formation properties with instruments located in the drill collars immediately above the drill bit. The LWD tools (on 6-3/4 inch collars) used during the GOM-JIP drilling program included the resistivity-at-the-bit GeoVision tool (GVR6), the EcoScope tool (DVD with APWD), the TeleScope MWD tool (TeleScope), a magnetic resonance while drilling tool (MWD-ProVision), and the azimuthal density neutron (VDN) tool. The only CWL tool deployed on this cruise was the FMS-sonic tool string, which consisted of the Formation MicroScanner (FMS), a general purpose inclinometer tool (GPIT), and the dipole shear sonic imager tool (DSI). The vertical seismic imager tool (VSI) was also deployed during the GOM-JIP drilling program. As noted above, LWD operations were conducted in the Atwater Valley 13-1 and 14-1 wells, and in the Keathley Canyon 151-2 well. Conventional wireline logging operations included the deployment of a dipole shear sonic imager tool (DSI) logging string and a vertical seismic imager tool in the Keathley Canyon 151-3 well. The downhole well log data from all four wells surveyed showed some evidence of gas hydrates. A review of the well log data from the two Atwater Valley wells shows little evidence of significant gas hydrate occurrences, other than several thin, possibly stratigrahically controlled gas-hydrate-bearing intervals. The LWD logs from these wells further suggests the presence of a complex pore water fluid regime, with variable well log inferred pore water salinities. It is important to highlight, however, that the well log and seismically inferred fluid salinity and possible free-gas feature associated with the Atwater 14-1 site is limited in spatial size and likely exhibits only local influence on gas hydrate stability conditions. LWD gamma ray measurements suggests that the Keathley Canyon 151-2 well penetrated mostly a fine-grained clay dominated sedimentary section, except for one thick sand section at 95-110 mbsf. There are also several other sand rich sections deeper in the well. The most notable characteristic of the Keathley Canyon 151-2 well is a high resistivity interval within the section from about 220 mbsf to 300 mbsf, which probably indicates the occurrence of gas hydrates. LWD derived resitivity-at-bit images from this high resistivity interval, also reveals the presence of numerous steeply dipping gas-hydrate filled fractures throughout this section. The well log data from the Keathley Canyon 151-2 well again shows that the occurrence gas hydrates is strongly influenced by the presence of reservoir type sediments, such as sand. In the case of the Keathley Canyon 151-2 well, we apparently found a fractured controlled gas hydrate occurrence.

Collett, T. S.; Conte, A.; Loh, L. L.; Hoong, H. F.; Goldberg, D. S.

2005-12-01

77

Geophysical well-log measurements in three drill holes at Salt Valley, Utah  

SciTech Connect

Three exploratory drill holes were drilled at Salt Valley, Utah, to study the geologic, physical, geochemical, and hydrologic properties of the evaporite sequence in the Permian Paradox Member of the Hermosa Formation. The results of these studies will be used to help to determine the suitability of salt deposits in the Paradox basin as a storage medium for radioactive waste material. The following geophysical well-log measurements were made in each of the three drill holes: (1) density, (2) neutron, (3) acoustic velocity, (4) normal resistivity, and (5) gamma ray. Widely spaced resistivity and conductivity well-log measurements were made in the deep drill hole. Each of these well-log measurements shows the division of the evaporite sequence into halite and interbed sections. At the present time the most useful well-logging measurements for determining the individual lithologies in an evaporite sequence are gamma ray, neutron, density, and acoustic velocity. The high resistivity contrast between the drilling fluid (0.5 ohm-m) and salt (10,000 ohm-m) makes it difficult to obtain quantitative measurements of electrical properties in an evaporite sequence. Tests of widely spaced electrode configurations show that the effects of the brine on the resistivity measurements can be reduced, and the depth of investigation increased, by increasing the source-receiver electrode spacing. Tests of a single-coil induction probe show good resolution of the contrasting electrical properties of the various interbed lithologies.

Daniels, J.J.; Hite, R.J.; Scott, J.H.

1980-01-01

78

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

79

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

80

SPE 159255-PP Rock Classification from Conventional Well Logs in Hydrocarbon-Bearing  

E-print Network

-determined inversion solution. Field cases in the Barnett and Haynesville shale gas plays show the importance of core formation. A case in the Haynesville formation suggests the possibility of identifying depositional with well logs. Core data and inversion results indicate homogeneity in the Haynesville formation case

Torres-Verdín, Carlos

81

Some contrast agents in oil well logging and in medical MRI.  

PubMed

Magnetite particles and paramagnetic ion chelates are used as contrast agents in both nuclear magnetism logging of oil wells and in medical MRI. An analytic expression for reduction of T2 for free precession signal decay (or gradient echoes) by magnetite particles does not depend on diffusion and agrees with published Monte Carlo computations. PMID:8464372

Brown, R J

1993-04-01

82

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

83

Analysis of well logging methods in volcanic and volcano sedimentary rocks from Pina petroleum field  

SciTech Connect

Petrophysical, petrological and geophysical methods have been applied to prospecting and well logging for several petroleum fields in Cuba. The most common reservoir in these fields are carbonate rocks. However, the Pina field, in the Central region of the island, distinguishes itself by the good quality of the oil and the volcano sedimentary and volcanic character of the reservoirs. These rocks have peculiar geophysical responses, which is why the study of these methods and the development of the interpretation methods is very important. Integrated geological and geophysical information was necessary during the drilling of wells in the Pina field in order to evaluate the hydrocarbon potential. GEONUC code permits us to use different ways to solve questions about interpretation of well logging in the volcanic sedimentary rocks. This code gives us the opportunity to analyze complex methods.

Rodriquez, N. [Empresa Geofisica, Havana (Cuba)

1996-09-01

84

Reservoir characterization of marine and permafrost associated gas hydrate accumulations with downhole well logs  

USGS Publications Warehouse

Gas volumes that may be attributed to a gas hydrate accumulation depend on a number of reservoir parameters, one of which, gas-hydrate saturation, can be assessed with data obtained from downhole well-logging devices. This study demonstrates that electrical resistivity and acoustic transit-time downhole log data can be used to quantify the amount of gas hydrate in a sedimentary section. Two unique forms of the Archie relation (standard and quick look relations) have been used in this study to calculate water saturations (S(w)) [gas-hydrate saturation (S(h)) is equal to (1.0 - S(w))] from the electrical resistivity log data in four gas hydrate accumulations. These accumulations are located on (1) the Blake Ridge along the Southeastern continental margin of the United States, (2) the Cascadia continental margin off the pacific coast of Canada, (3) the North Slope of Alaska, and (4) the Mackenzie River Delta of Canada. Compressional wave acoustic log data have also been used in conjunction with the Timur, modified Wood, and the Lee weighted average acoustic equations to calculate gas-hydrate saturations in all four areas assessed.

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

2000-01-01

85

An application of hidden Markov model for lithological characterization based on well-logging data  

NASA Astrophysics Data System (ADS)

We have applied hidden Markov model (HMM) for the prediction of lithology based on the emitted signal to test the feasibility of lithological estimations based on indirect well-logging data. For the purpose, synthetic borehole data is assumed and the forward-backward algorithm of HMM is adopted which requires lithological transition probability, lithology-signal emission probabilities, and initial distribution probability as input variables. The transition probabilities used are assumed to be directly acquirable from the adjacent boreholes in two directions (i.e. upward and downward) as one-step transition probability matrices. To make simple exercise case, the geophysical logging data is assumed and, from the data, the emission probability is acquired in a form of probability distributions by applying Bayesian classifier for the corresponding lithology. The advantageous aspect of lithology prediction with hidden Markov model with Bayesian classifier is tested by composing two benchmark cases: only Bayesian classifier is considered with one-logging data (Case I-(a)) and two-logging data (Case I-(b)) are available; Bayesian updating is considered to make the emission probability based on hidden Markov mole(Case II). On the other hand, the prediction is made by considering Bayesian classifier and hidden Markov model (Case III). All in all, the predictions of Case III is superior to Case I-(a-b) and Case II by resulting in stable and better estimation.

Jeong, J.; Ahn, J.; Lee, S.; Park, E.

2013-12-01

86

Experiment on estimating thermal conductivity of sedimentary rocks from oil well logging  

SciTech Connect

Oil well logs are an important source of geothermal data for studying regional tectonics, reconstructing the evolution of sedimentary basins, and theorizing petroleum generation, migration, and accumulation. A more satisfactory, less laborious method of estimating the thermal conductivity of sedimentary rocks is badly needed. The thermal conductivity of cores from two gas wells in France was measured and correlated with neutron porosity index, sonic interval travel time, bulk density, and gamma-ray logs. To obtain reasonable predictions of conductivity, data were segregated into lithologic groups such as sand-shale, carbonate-shale, and carbonate-sand. A set of regression coefficients in the equation that predicts the conductivity from the logs was calculated for each group. The correlation coefficients between the measured and predicted conductivities of the core samples were 0.81, 0.75, and 0.61, respectively, for the three lithologic groups. The average percent difference between the measured and the calculated conductivities for the lithologies likely to be encountered in practice is 13.4%. The authors expect this figure can be reduced to 10% by enlarging the data base for calculating the regression coefficients. In the same basin or oil field, the relative errors from well to well probably will be 6% or smaller because the lithology will be nearly homogeneous. 4 figures, 5 tables.

Vacquier, V.; Mathieu, Y. Legendre, E.; Blondin, E.

1988-06-01

87

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

88

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

NASA Astrophysics Data System (ADS)

An experimental protocol is described that allows two-dimensional (2D) nuclear magnetic resonance (NMR) correlations of apparent diffusion coefficient Dapp and effective transverse relaxation time T2,eff to be acquired on a bench-top spectrometer using pulsed field gradients (PFG) in such a manner as to emulate Dapp - T2,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 - T2 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 T2 samples in general.

Mitchell, J.; Fordham, E. J.

2011-10-01

89

Investigation of Waikele well no 2401-01, Oahu, Hawaii; pumping test, well logs and water quality  

USGS Publications Warehouse

Field tests indicate that an abandoned well (No. 2401-01) near the confluence of Waikele and Kipapa Streams, Oahu, Hawaii, can be reactivated to produce potable water at a rate of 400-500 gallons per minute. Previous tests in 1946 and 1954 indicated that the well tapped the brackish transition zone which inderlies the Ghyben-Herzberg lens of the Pearl Harbor aquifer. Results of this study, based on geologic and geophysical logs of the wall, as well as on pumping test and water-quality data, indicate that the slightly brackish water produced by the well results from brackish irrigation return water. It does not appear that pumping from this well will cause seawater upconing or intrusion. (USGS)

Eyre, P.R.

1983-01-01

90

Geophysical logging of bedrock wells for geothermal gradient characterization in New Hampshire, 2013  

USGS Publications Warehouse

The U.S. Geological Survey, in cooperation with the New Hampshire Geological Survey, measured the fluid temperature of groundwater and other geophysical properties in 10 bedrock wells in the State of New Hampshire in order to characterize geothermal gradients in bedrock. The wells selected for the study were deep (five ranging from 375 to 900 feet and five deeper than 900 feet) and 6 had low water yields, which correspond to low groundwater flow from fractures. This combination of depth and low water yield reduced the potential for flow-induced temperature changes that would mask the natural geothermal gradient in the bedrock. All the wells included in this study are privately owned, and permission to use the wells was obtained from landowners before geophysical logs were acquired for this study. National Institute of Standards and Technology thermistor readings were used to adjust the factory calibrated geophysical log data. A geometric correction to the gradient measurements was also necessary due to borehole deviation from vertical. Maximum groundwater temperatures at the bottom of the logs ranged from 11.2 to 15.4 degrees Celsius. Geothermal gradients were generally higher than those typically reported for other water wells in the United States. Some of the high gradients were associated with high natural gamma emissions. Groundwater flow was discernible in 4 of the 10 wells studied but only obscured the part of the geothermal gradient signal where groundwater actually flowed into, out of, or through the well. Temperature gradients varied by mapped bedrock type but can also vary by localized differences in mineralogy or rock type within the wells.

Degnan, James R.; Barker, Gregory; Olson, Neil; Wilder, Leland

2014-01-01

91

Temperature logging of groundwater in bedrock wells for geothermal gradient characterization in New Hampshire, 2012  

USGS Publications Warehouse

The U.S. Geological Survey, in cooperation with the New Hampshire Geological Survey, measured the fluid temperature of groundwater in deep bedrock wells in the State of New Hampshire in order to characterize geothermal gradients in bedrock. All wells selected for the study had low water yields, which correspond to low groundwater flow from fractures. This reduced the potential for flow-induced temperature changes that would mask the natural geothermal gradient in the bedrock. All the wells included in this study were privately owned, and permission to use the wells was obtained from homeowners before logging. Maximum groundwater temperatures at the bottom of the logs were between 11.7 and 17.3 degrees Celsius. Geothermal gradients were generally higher than typically reported for other water wells in the United States. Some of the high gradients were associated with high natural gamma emissions. Groundwater flow was discernible in 5 of the 10 wells studied but only obscured the portion of the geothermal gradient signal where groundwater actually flowed through the well. Temperature gradients varied by mapped bedrock type but can also vary by differences in mineralogy or rock type within the wells.

Degnan, James; Barker, Gregory; Olson, Neil; Wilder, Leland

2012-01-01

92

Manchester code telemetry system for well logging using quasi-parallel inductive-capacitive resonance  

NASA Astrophysics Data System (ADS)

In this paper, a quasi-parallel inductive-capacitive (LC) resonance method is proposed to improve the recovery of MIL-STD-1553 Manchester code with several frequency components from attenuated, distorted, and drifted signal for data telemetry in well logging, and corresponding telemetry system is developed. Required resonant frequency and quality factor are derived, and the quasi-parallel LC resonant circuit is established at the receiving end of the logging cable to suppress the low-pass filtering effect caused by the distributed capacitance of the cable and provide balanced pass for all the three frequency components of the Manchester code. The performance of the method for various encoding frequencies and cable lengths at different bit energy to noise density ratios (Eb/No) have been evaluated in the simulation. A 5 km single-core cable used in on-site well logging and various encoding frequencies were employed to verify the proposed telemetry system in the experiment. Results obtained demonstrate that the telemetry system is feasible and effective to improve the code recovery in terms of anti-attenuation, anti-distortion, and anti-drift performances, decrease the bit error rate, and increase the reachable transmission rate and distance greatly.

Xu, Lijun; Chen, Jianjun; Cao, Zhang; Liu, Xingbin; Hu, Jinhai

2014-07-01

93

Manchester code telemetry system for well logging using quasi-parallel inductive-capacitive resonance.  

PubMed

In this paper, a quasi-parallel inductive-capacitive (LC) resonance method is proposed to improve the recovery of MIL-STD-1553 Manchester code with several frequency components from attenuated, distorted, and drifted signal for data telemetry in well logging, and corresponding telemetry system is developed. Required resonant frequency and quality factor are derived, and the quasi-parallel LC resonant circuit is established at the receiving end of the logging cable to suppress the low-pass filtering effect caused by the distributed capacitance of the cable and provide balanced pass for all the three frequency components of the Manchester code. The performance of the method for various encoding frequencies and cable lengths at different bit energy to noise density ratios (Eb/No) have been evaluated in the simulation. A 5 km single-core cable used in on-site well logging and various encoding frequencies were employed to verify the proposed telemetry system in the experiment. Results obtained demonstrate that the telemetry system is feasible and effective to improve the code recovery in terms of anti-attenuation, anti-distortion, and anti-drift performances, decrease the bit error rate, and increase the reachable transmission rate and distance greatly. PMID:25085159

Xu, Lijun; Chen, Jianjun; Cao, Zhang; Liu, Xingbin; Hu, Jinhai

2014-07-01

94

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

95

Interpreting sedimentary growth structures from well log and seismic data (with examples)  

SciTech Connect

Growth structures develop when sediments are deposited during tectonic events such as normal and thrust faulting, diapirism, and subsidence. Information about sedimentary and tectonic history can be obtained by analyzing the depths of stratigraphic horizons within growth structures, either from well log or depth-corrected seismic data. For example, differences in depth between correlatable horizons are determined for two wells ({Delta}d), and then plotted versus total depth in the structurally higher well (d). Positive slopes on this graph indicate expanded sedimentary sections, negative slopes are condensed sections, and curves with no slope are environments free of differential tectonic motion. Changes in either sedimentation or tectonic conditions create discontinuities or changes in slope. Thus, the growth plots provide strong constraints on any interpretation. The plot of {Delta}d versus d helps to distinguish faults from unconformities in well log data, to identify hard to locate sequence boundaries, and to locate stratigraphic miscorrelations, which appear as outlying points from the curve. This method for analyzing sedimentary growth structures can be applied to any tectonic or sedimentary environment and has many applications.

Bischke, R.E. [Princeton Univ. Princeton, NJ (United States)

1994-06-01

96

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

97

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

98

Exhumation Estimates Derived from Sonic Well Log Data in the Colorado Plateau - Southern Rocky Mountain Region  

NASA Astrophysics Data System (ADS)

Interval transit time, which is the reciprocal of sonic velocity, can be determined from sonic geophysical well logs and used to estimate exhumation. Interval transit time decreases with increasing burial depth according to a compaction curve calibrated for each rock unit examined. Because rock compaction is an irreversible process, rock units that are at a depth shallower than their maximum burial depth will have a lower-than-expected ? interval travel time relative to the calibrated compaction curve. This technique is very useful because the sonic logs are ubiquitous and a large amount of data can be acquired and analyzed in a relatively short time, so that exhumation trends over a large area can be examined. Interval transit time on sonic logs generally decreases exponentially as a function of depth in Cretaceous shales in two Laramide basins, the Raton Basin and the San Juan Basin, in northern New Mexico and southern Colorado. The average interval transit time for the Mancos Shale in the San Juan Basin at depths shallower than 3000 feet (914 m) ranges from 75 to 105 ?s/ft and shows a pronounced decrease with depth. In contrast, interval travel time averages about 70 to 80 ?s/ft at depths greater than about 3000 feet and the average is insensitive to depth. The interval transit time of the Mancos Shale north of Township 30 N in New Mexico actually increases with increasing depth, suggesting that some mechanism other than simple compaction (over pressuring or a previously unrecognized facies change) controls the velocity in this area. The average interval transit time for the Pierre Shale in the Raton Basin ranges from 65 to 110 ?s/ft and is generally correlated with depth. The calibrated compaction curve for the Late Cretaceous Pierre Shale in the Raton Basin, based on data from ten wells, is similar to the compaction curve for the Late Cretaceous Mancos Shale in the San Juan Basin, which is determined from approximately one hundred well logs. The amount of exhumation recorded by the shale sonic data in the Raton Basin is slightly higher (maximum exhumation of 1.5 km; typically less than 1.2 km) than that in the San Juan Basin (maximum exhumation 1.2 km, typically less than 1 km). Maximum exhumation is near the southern end of the basin in both areas.

Kelley, S. A.

2005-12-01

99

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

100

Evaluation of Non-Nuclear Techniques for Well Logging: Technology Evaluation  

SciTech Connect

This report presents an initial review of the state-of-the-art nuclear and non-nuclear well logging methods and seeks to understand the technical and economic issues if AmBe, and potentially other isotope sources, are reduced or even eliminated in the oil-field services industry. Prior to considering alternative logging technologies, there is a definite need to open up discussions with industry regarding the feasibility and acceptability of source replacement. Industry views appear to range from those who see AmBe as vital and irreplaceable to those who believe that, with research and investment, it may be possible to transition to electronic neutron sources and employ combinations of non-nuclear technologies to acquire the desired petro-physical parameters. In one sense, the simple answer to the question as to whether petro-physical parameters can be sensed with technologies other than AmBe is probably "Yes". The challenges come when attention turns to record interpretation. The many decades of existing records form a very valuable proprietary resource, and the interpretation of subtle features contained in these records are of significant value to the oil-gas exploration community to correctly characterize a well. The demonstration of equivalence and correspondence/correlation between established and any new sensing modality, and correlations with historic records is critical to ensuring accurate data interpretation. Establishing the technical basis for such a demonstration represents a significant effort.

Bond, Leonard J.; Denslow, Kayte M.; Griffin, Jeffrey W.; Dale, Gregory E.; Harris, Robert V.; Moran, Traci L.; Sheen, David M.; Schenkel, Thomas

2010-11-01

101

Geophysical Well-Log Analysis In Characterizing The Hydrology Of Crystalline Rocks Of The Canadian Shield  

E-print Network

A full suite of geophysical logs, including nuclear, electric, acoustic transit-time, acoustic waveform, and acoustic televiewer logs, and high-resolution flowmeter measurements have been used to investigate the lithologic ...

Paillet, F . L.

1988-01-01

102

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

103

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

104

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

105

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

106

Pore pressure prediction from well logs: Methods, modifications, and new approaches  

NASA Astrophysics Data System (ADS)

Pore pressures in most deep sedimentary formations are not hydrostatic; instead they are overpressured and elevated even to more than double of the hydrostatic pressure. If the abnormal pressures are not accurately predicted prior to drilling, catastrophic incidents, such as well blowouts and mud volcanoes, may take place. Pore pressure calculation in a hydraulically-connected formation is introduced. Fracture gradient prediction methods are reviewed, and the minimum and maximum fracture pressures are proposed. The commonly used empirical methods for abnormal pore pressure prediction from well logs are then reviewed in this paper. Eaton's resistivity and sonic methods are then adapted using depth-dependent normal compaction equations for pore pressure prediction in subsurface formations. The adapted methods provide a much easier way to handle normal compaction trendlines. In addition to the empirical methods, the theoretical pore pressure modeling is the fundamental to understand the mechanism of the abnormal pressure generation. A theoretical pore pressure-porosity model is proposed based on the primary overpressure generation mechanism — compaction disequilibrium and effective stress-porosity-compaction theory. Accordingly, pore pressure predictions from compressional velocity and sonic transit time are obtained using the new theoretical model. Case studies in deepwater oil wells illustrate how to improve pore pressure prediction in sedimentary formations.

Zhang, Jincai

2011-09-01

107

Prediction of gas production using well logs, Cretaceous of north-central Montana  

USGS Publications Warehouse

Cretaceous gas sands underlie much of east-central Alberta and southern Saskatchewan, eastern Montana, western North Dakota, and parts of South Dakota and Wyoming. Estimates of recoverable biogenic methane from these rocks in the United States are as high as 91 TCF. In northern Montana, current production is localized around a few major structural features, while vast areas in between these structures are not being exploited. Although the potential for production exists, the lack of commercial development is due to three major factors: 1) the lack of pipeline infrastructure; 2) the lack of predictable and reliable rates of production; and 3) the difficulty in recognizing and selecting potentially productive gas-charged intervals. Unconventional (tight), continuous-type reservoirs, such as those in the Cretaceous of the northern Great Plains, are not well suited for conventional methods of formation evaluation. Pay zones frequently consist only of thinly laminated intervals of sandstone, silt, shale stringers, and disseminated clay. Potential producing intervals are commonly unrecognizable on well logs, and thus are overlooked. To aid in the identification and selection of potential producing intervals, a calibration system is developed here that empirically links the 'gas effect' to gas production. The calibration system combines the effects of porosity, water saturation, and clay content into a single 'gas-production index' (GPI) that relates the in-situ rock with production potential. The fundamental method for isolating the gas effect for calibration is a crossplot of neutron porosity minus density porosity vs gamma-ray intensity. Well-log and gas-production data used for this study consist of 242 perforated intervals from 53 gas-producing wells. Interval depths range from about 250 to 2400 ft. Gas volumes in the peak calendar year of production range from about 4 to 136 MMCF. Nine producing formations are represented. Producing-interval data show that porosity and gas production are closely linked to clay volume. Highest porosities and maximum gas production occur together at an intermediate clay content of about 12% (60 API). As clay volume exceeds 35% (130 API), minimum porosity required for production increases rapidly, and the number of potential producing intervals declines. Gas production from intervals where clay volume exceeds 50% is rare. Effective porosities of less than about 8% are probably inadequate for commercial gas production in these rocks regardless of clay content.

Hester, T. C.

1999-01-01

108

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

109

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

110

Comparison of Surface Temperature Histories From The Inversion of Well Temperature Logs and From Tree Rings  

NASA Astrophysics Data System (ADS)

The majority of global and regional representations of ground surface temperature (GST) history for the last several centuries from recent literature relate changes in warming and cooling events to a recent base period temperature levels (1961-1990 average) or to the most recent mean annual temperature. The GST histories, when compared with proxy reconstructed histories of mean surface air temperature (SA T) change derived mainly from tree rings, show a significantly lower level of mean annual GST (0.5 C or more) for the 16th century to the mid-19th century. Some of o this difference can be attributed to the temporal detrending process used in the tree ring method which is intended to mute long-term growth trends that may be present in the data, to the growing season signal derived from the trees as opposed to the annual signal represented by the GST history, and to the use of different base periods by the two methods. We also demonstrate that these differences are present in the recent two centuries as well and are due to other factors. Analysis of North American (mostly Canadian) GST histories derived from well temperature logs and historical SAT time series shows that the differences are due to processes such as land clearing and the GST versus SAT tracking problem for northern latitudes during times of frost.

Skinner, Walter; Majorowicz, Jacek

111

40 CFR 146.66 - Logging, sampling, and testing prior to new well operation.  

Code of Federal Regulations, 2010 CFR

...logs and tests shall be run to determine or verify the depth, thickness, porosity, permeability, and rock type of, and the salinity of any entrained fluids in, all relevant geologic units to assure conformance with performance standards in §...

2010-07-01

112

40 CFR 146.66 - Logging, sampling, and testing prior to new well operation.  

Code of Federal Regulations, 2011 CFR

...logs and tests shall be run to determine or verify the depth, thickness, porosity, permeability, and rock type of, and the salinity of any entrained fluids in, all relevant geologic units to assure conformance with performance standards in §...

2011-07-01

113

Directional drilling equipment and techniques for deep hot granite wells  

SciTech Connect

Conventional directional drilling technology has been extended and modified to drill the first well of a subsurface geothermal energy extraction system at the Fenton Hill, New Mexico, Hot dry Rock (HDR) experimental site. Completing the first of a two-wellbore HDR system has resulted in the definition of operational limitations of many conventional directional drilling tools, instrumentation and techniques. The successful completion of the first wellbore, Energy Extraction Well No. 2 (EE-2), to a measured depth of 15,300 ft (4.7 km) in granite reservoir rock with a bottomhole temperature of 530/sup 0/F (275/sup 0/C) required the development of a new high temperature downhole motor and modification of existing wireline-conveyed steering tool systems. Conventional rotary-driven directional assemblies were successfully modified to accommodate the very hard and abrasive rock encountered while drilling nearly 8500 ft (2.6 km) of directional hole to a final inclination of 35/sup 0/ from the vertical at a controlled azimuthal orientation.

Brittenham, T.L.; Sursen, G.; Neudecker, J.W.; Rowley, J.C.; Williams, R.E.

1980-01-01

114

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

115

Persistence analysis in geophysical spatial series: an application to well log data  

NASA Astrophysics Data System (ADS)

Fractal geometry is the field of Mathematics that studies the properties and behavior of fractals. It was already applied to several areas of Science, explaining many situations that cannot be described by classical geometry. A fractal is a geometric object that can be divided into several parts, each one similar to the original object. Fractal geometry has been used frequently to characterize and describe natural models. Its applications range from microscopic dimensions to the understanding of macroscopic processes. Many geophysical variables seem to have a scale behavior, which means that their power spectrum, P(f), seem to be proportional to some frequency f, that is, ln[P(f)] = - b ln(f), where b is called the spectral exponent. Following this principle, we propose to study a set of well log data, collected in the Jequitinhonha basin (Brazil), through the methods of spectral analysis and re-scaled analysis. When the spectral exponent varies from 0.5 to 1.5, the physical property is said to have a 1/f noise. One method to verify the long range persistence is through the re-scaled (R/S) analysis, with computes the Hurst coefficient H. H and the exponent b are related by bcum = 2H + 1, where bcum is cumulative spectral exponent of the sequence with exponent b. The spatial series are the following well data: acoustic velocity, gamma ray, induction deep resistivity, porosity, density, resistivity average, and spontaneous potential. For each parameter, we computed the spectral exponent b, and the coefficient H, attesting the variability of the available data. The results for H were coherent with other works mentioned in the literature. We obtained 0.6 < H < 0.9 for both methods, in such a way that all the parameters behave as persistent. The importance of such study is to show that different methods provided the same results, which is a significant fact for complex systems. The knowledge of H also provides the computation of the fractal dimension, as well as to understand the complexity of layer sedimentation phenomenon.

Bassrei, A.

2008-12-01

116

2D/3D Electromagnetic sounding and well log integration on Santos Basin, Brazil  

NASA Astrophysics Data System (ADS)

Magnetotellurics (MT) is a naturally induced electromagnetic technique used to map resistivity contrasts in the subsurface of the earth. The method uses the time-varying natural electric and magnetic fields incident on the earth's surface as signal source. The method has been successfully used to achieve marine exploration objectives such as imaging sub-basalts, carbonates and subsalts in situations where seismic imaging is poor. A marine magnetotelluric survey on Santos basin in the southeast of Brazil has generated high quality data in 96 sites split in three parallel profiles in NW-SE direction along a 160 km central line and two other lines, east and west, with approximately 54 km long each one. All sites were submitted to some stages of processing to avoid noise amount and reach quality improvement. Firstly, we start applying 2D inversion to MT data and we obtained two-dimensional models with very good resolution for the three profiles and they are consistent each other. We have used well log data to provide priori resistivity information for magnetotelluric models and make correlation from different data sets. The study points out that the profiles can be imaged by two-dimensional except by small parts in the models with low misfits. These parts are associated with some interesting geological structures of highlighted importance as salt domes and diapirs. The halokinetic structures have special geometries hence they are better explained by three-dimensional approach. However, it is more appropriate utilize a 3D imaging in order to reach the best model with minor uncertainties. Recently, the number of publications regarding 3D magnetotelluric inversion has increased and it is due to the fact of the effort in performing a better characterization of the research area. It is because the magnetotelluric method has been increasingly accepted as powerful technique capable to predict valuable information. Currently we are performing a 3D inversion using all profiles with a grid of approximately 160 x 6 km2 and the first results will be shown at the meeting.

Pinto, V. R.; Fontes, S. L.

2011-12-01

117

Improved Detection of Bed Boundaries for Petrophysical Evaluation with Well Logs: Applications to Carbonate and Organic-Shale Formations  

E-print Network

: Applications to Carbonate and Organic-Shale Formations Zoya Heidari, SPE, Texas A&M University and Carlos, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper of well logs acquired in organic shales and carbonates is challenging because of the presence of thin beds

Torres-Verdín, Carlos

118

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

119

Uncertainty Analysis in Upscaling Well Log data By Markov Chain Monte Carlo Method  

E-print Network

of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair of Committee, Richard L. Gibson Committee Members, Yuefeng Sun Thomas A. Blasingame Head of Department, Andreas K. Kronenberg May 2009 Major Subject: Geophysics iii ABSTRACT Uncertainty.... Therefore, the number and location of blocked layers can be effectively quantified in spite of uncertainties in upscaling log data. v To my parents who nurtured me in faith, love, and perseverance vi ACKNOWLEDGMENTS Praise and glory be to the Almighty God...

Hwang, Kyubum

2010-01-16

120

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.

2007-01-01

121

Paleosols: Their use in well log correlation and seismic stratigraphy in Cenozoic basin-fill, southwestern Montana  

SciTech Connect

The use of paleosols as sequence boundary markers has recently been shown to be one of the most important tools for the interpretation of seismic data in regions of continental Cenozoic basin-fill material. Calcic paleosols and their defined sequence boundaries have been previously mapped on the surface and tied to seismic reflection data, and now can be delineated on well logs. Analyses of sonic and density logs from wells in the Deerlodge Valley, southwestern Montana, has resulted in the identification of several relatively thin, high velocity/high density zones which exist within the Cenozoic basin-fill. Zone thickness varies from 1 to 1.5 meters, and the zones are stacked up to as much as 40 meters. Density changes within the zones up to 0.6 g/cm[sup 3]. Velocity changes up to 1,660 meters/second. Well cutting chips from the high velocity/high density zones exhibit pedogenic features associated with calcic paleosols, such as clastic grains floating in micrite, grains corroded by calcite, and calcified root filaments. The authors generate synthetic seismograms from the sonic and density well logs which they analyze, and tie the seismograms to seismic reflection data using bright reflectors. The bright reflectors are interpreted as sequence boundaries on the seismic data and can be projected to the surface where they are associated with stacked zones of calcic paleosols which mark surface sequence boundaries.

Hanneman, D.L. (Whitehall Geogroup, Inc., Whitehall, MT (United States)); Wideman, C.J. (Montana Coll. of Mineral Science and Technology, Butte, MT (United States). Dept. of Geophysical Engineering); Halvorson, J. (Montana Board of Oil and Gas Conversation, Billings, MT (United States))

1992-01-01

122

State-Of-The-Art in Permeability Determination From Well Log Data: Part 1-A Comparative Study, Model Development  

E-print Network

K A1 S2 K A1 Sp 2 K A1 3 So 2 (1 )2 (1) (2) (3) SPE 30978 State-Of-The-Art in Permeability Determination From Well Log Data: Part 1- A Comparative Study, Model Development Balan, B., Mohaghegh, S., Ameri to determine and predict is permeability. A great amount of work was done by several investigators in the1

Mohaghegh, Shahab

123

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

SciTech Connect

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 effective for thick, rapidly deposited slope and basin sediments, such as in the Plio-Pleistocene of the Gulf of Mexico basin. The general sequence-stratigraphic model consists of a depositional sequence with lowstand basin floor fan, slope fan, and prograding complex, transgressive systems tract, and highstand systems tract. Each systems tract is deposited at a predictable position in an interpreted eustatic cycle and has recognizable signatures in well logs and seismic data. Any given basin to which this model is applied is strongly controlled by its own tectonic subsidence and accommodation history, and by the type and rate of sediment supply, but the higher frequency eustatic cyclicity is superposed on the other basinal controls. A typical depositional model for the Plio-Pleistocene of the Gulf of Mexico basin is a diapir-controlled subbasin associated with a large contemporaneous expansion fault. The environment of deposition is closely related to the history of fault development. Reservoir sand distribution is characteristic and predictable for each systems tract. Carefully planned evaluation and completion techniques are based on these characteristics.

Mitchum, R.M. Jr. (R M Mitchum Exploration Inc., Houston, TX (United States)); Sangree, J.B. (Sangree Exploration Inc., Houston, TX (United States)); Vail, P.R. (Rice Univ. Houston, TX (United States)); Wornar, W.W. (Microstrat Inc., Houston, TX (United States))

1991-03-01

124

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

125

40 CFR 146.87 - Logging, sampling, and testing prior to injection well operation.  

...sampling, and testing prior to injection well operation. 146.87 Section...sampling, and testing prior to injection well operation. (a) During the...and construction of a Class VI injection well, the owner or operator...

2014-07-01

126

40 CFR 146.87 - Logging, sampling, and testing prior to injection well operation.  

Code of Federal Regulations, 2012 CFR

...sampling, and testing prior to injection well operation. 146.87 Section...sampling, and testing prior to injection well operation. (a) During the...and construction of a Class VI injection well, the owner or operator...

2012-07-01

127

40 CFR 146.87 - Logging, sampling, and testing prior to injection well operation.  

Code of Federal Regulations, 2013 CFR

...sampling, and testing prior to injection well operation. 146.87 Section...sampling, and testing prior to injection well operation. (a) During the...and construction of a Class VI injection well, the owner or operator...

2013-07-01

128

Prediction of Compressional, Shear, and Stoneley Wave Velocities from Conventional Well Log Data Using a Committee Machine with Intelligent Systems  

NASA Astrophysics Data System (ADS)

Measurement of compressional, shear, and Stoneley wave velocities, carried out by dipole sonic imager (DSI) logs, provides invaluable data in geophysical interpretation, geomechanical studies and hydrocarbon reservoir characterization. The presented study proposes an improved methodology for making a quantitative formulation between conventional well logs and sonic wave velocities. First, sonic wave velocities were predicted from conventional well logs using artificial neural network, fuzzy logic, and neuro-fuzzy algorithms. Subsequently, a committee machine with intelligent systems was constructed by virtue of hybrid genetic algorithm-pattern search technique while outputs of artificial neural network, fuzzy logic and neuro-fuzzy models were used as inputs of the committee machine. It is capable of improving the accuracy of final prediction through integrating the outputs of aforementioned intelligent systems. The hybrid genetic algorithm-pattern search tool, embodied in the structure of committee machine, assigns a weight factor to each individual intelligent system, indicating its involvement in overall prediction of DSI parameters. This methodology was implemented in Asmari formation, which is the major carbonate reservoir rock of Iranian oil field. A group of 1,640 data points was used to construct the intelligent model, and a group of 800 data points was employed to assess the reliability of the proposed model. The results showed that the committee machine with intelligent systems performed more effectively compared with individual intelligent systems performing alone.

Asoodeh, Mojtaba; Bagheripour, Parisa

2012-01-01

129

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

130

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

131

Well-log based prediction of temperature models in the exploration of sedimentary settings: Examples from the North German Basin  

NASA Astrophysics Data System (ADS)

Temperature-depth distributions are pivotal in subsurface studies in academia as well as in georesources applications. In this regard, high-resolution temperature profiles, logged under equilibrium thermal borehole conditions, are the ultimate measure. However there are circumstances in which these measurements are not available or only measured to a certain depth so that a temperature model needs to developed. A prerequisite for such a model is the knowledge of the regional heat flow and the geological conditions translated into lithology and thermal rock properties. For the determination of the rock thermal conductivity (TC) we propose a two-step procedure: (1) the use of standard petrophysical well log and (2) the inversion of predicted TC to temperature gradients by applying Fourier's law of heat conduction. The prediction of TC is solved by using set of equations (Fuchs & Förster, 2014) developed for matrix TC of sedimentary rocks. The equations resulted from a statistical analysis of an artificial set of mineral assemblages (consisting of 15 rock-forming minerals) typical for the different types of sedimentary rocks. The matrix TC was transformed into bulk TC by using a well-log derived porosity. TC vs. depth profiles corrected for in situ (p, T) conditions finally were used in conjunction with a published site-specific heat-flow value to model a temperature profile. The methodology is shown on the example of a 4-km deep borehole at Hannover in the North German Basin. This borehole, drilled for geothermal use, penetrates thick Mesozoic sediments and terminates in the Triassic Middle-Buntsandstein formation. The temperature computation was performed, inter alia, for a borehole section in a depth range between approx. 2,320 and 3,750 m. The applied approach is able to match both predicted and measured equilibrium borehole temperature profiles with a resulting uncertainty of less than 5 %. Interval temperature gradients vary on average by < 3 °C/km.

Fuchs, Sven; Wonik, Thomas; Förster, Andrea

2014-05-01

132

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

133

Integration of ANFIS, NN and GA to determine core porosity and permeability from conventional well log data  

NASA Astrophysics Data System (ADS)

Routine core analysis provides useful information for petrophysical study of the hydrocarbon reservoirs. Effective porosity and fluid conductivity (permeability) could be obtained from core analysis in laboratory. Coring hydrocarbon bearing intervals and analysis of obtained cores in laboratory is expensive and time consuming. In this study an improved method to make a quantitative correlation between porosity and permeability obtained from core and conventional well log data by integration of different artificial intelligent systems is proposed. The proposed method combines the results of adaptive neuro-fuzzy inference system (ANFIS) and neural network (NN) algorithms for overall estimation of core data from conventional well log data. These methods multiply the output of each algorithm with a weight factor. Simple averaging and weighted averaging were used for determining the weight factors. In the weighted averaging method the genetic algorithm (GA) is used to determine the weight factors. The overall algorithm was applied in one of SW Iran’s oil fields with two cored wells. One-third of all data were used as the test dataset and the rest of them were used for training the networks. Results show that the output of the GA averaging method provided the best mean square error and also the best correlation coefficient with real core data.

Ja'fari, Ahmad; Hamidzadeh Moghadam, Rasoul

2012-10-01

134

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

135

Interpretation of Array Production Logging Measurements in Horizontal Wells for Flow Profile  

E-print Network

.................................................... 15 2.3 Phase Distribution Determination ........................................................ 17 2.4 Calibration of Spinner Flowmeter Responses ...................................... 17 3. FIELD CASE STUDY... being encountered. Curtis (1967) present an approach applying in multiple-phase flow from vertical wells, in this approach the spinner flowmeter are calibrated based on the surface flow rate translated to the condition of downhole temperature...

Liao, Lulu

2013-12-12

136

Neural network modelling and classification of lithofacies using well log data: a case study from KTB borehole site  

NASA Astrophysics Data System (ADS)

A novel approach based on the concept of super self-adapting back propagation (SSABP) neural network has been developed for classifying lithofacies boundaries from well log data. The SSABP learning paradigm has been applied to constrain the lithofacies boundaries by parameterzing three sets of well log data, that is, density, neutron porosity and gamma ray obtained from the German Continental Deep Drilling Project (KTB). A multilayer perceptron (MLP) neural networks model was generated in a supervised feed-forward mode for training the published core sample data. A total of 351 pairs of input and output examples were used for self-adaptive network learning and weight and bias values were appropriately updated during each epoch according to the gradient-descent momentum scheme. The actual data analysis suggests that the SSABP network is able to emulate the pattern of all three sets of KTB data and identify lithofacies boundaries correctly. The comparisons of the maximum likelihood geological sections with the available geological information and the existing geophysical findings over the KTB area suggest that, in addition to the known main lithofacies boundaries units, namely paragneisses, metabasites and heterogeneous series containing partly calc-silicate bearing paragneisses-metabasites and alternations of former volcano-sedimentary sequences, the SSABP neural network technique resolves more detailed finer structures embedded in bigger units at certain depths over the KTB region which seems to be of some geological significance. The efficacy of the method and stability of results was also tested in presence of different levels of coloured noise. The test results suggest that the designed network topology is considerably unwavering for up to 20 per cent correlated noise; however, adding more noise (~50 per cent or more) degrades the results. Our analyses demonstrate that the SSABP based approach renders a robust means for the classification of complex lithofacies successions from the KTB borehole log data and thus may provide useful guide/information for understanding the crustal inhomogeneity and structural discontinuity in many other regions.

Maiti, Saumen; Krishna Tiwari, Ram; Kümpel, Hans-Joachim

2007-05-01

137

Assessment of seal quality for potential storage sites in the Norwegian North Sea from well log data  

NASA Astrophysics Data System (ADS)

Fluid migration through caprocks is a crucial process when it comes to evaluate their sealing capacity for underground CO2 storage. Migration mechanisms such as flow through fault systems or along wells are quite easily identified by their relatively large size and because these features can be monitored by the use of reflection seismic data or well logs. However, microcracks in rocks, which can allegedly cause fluid migration through tight rocks, are difficult to detect from large scale observations and can only be deduced from thorough investigation. The objective of this work is to evaluate the likelihood of microfracture networks in potential seals (shales) through the analysis of well log data. This study focuses on the Upper Jurassic and Lower Cretaceous shale succession in the Norwegian North Sea. The main target of the study is the Draupne Formation (upper Jurassic) found in the Horda Platform / Viking Graben area. It has been deposited syn-rift during the second episode of the Viking graben formation in the Upper Jurassic, and thus has a burial depth ranging from 914 to 4573 m. This formation is identified in well logs by its sharp decrease in ultrasonic velocity and density, and specifically high resistivity and gamma ray readings. Other studied shale formations include the rest of the Viking Group (Heather Formation), the Tyne Group in the Central Graben (Farsund, Haugesund and Mandal) and the Boknfjord Group in the Norwegian-Danish Basin (Egersund, Flekkefjord, Sauda and Tau). Public well log data from 104 boreholes in the Norwegian sector of the North Sea have been analyzed and among them, 87 had a complete set of logs that are necessary for our analysis: ultrasonic velocities, gamma ray, density and resistivity. This study illustrates that the first-order variation of the ultrasonic velocity for the Draupne Formation in the Norwegian North Sea is of course due to depth. Diagenesis, whether mechanical or chemical, stiffens the rock by strengthening the grain contacts and/or cementing them. This increases the ultrasonic velocity through the rock. The depth at which the transition between mechanical and chemical transition, together with the geothermal gradient study, help us to separate areas where these identified shales have a ductile rheology (softer rock, self healing low-conductivity cracks) from those where stiffening by secondary quartz cementation yields a brittle rheology (stronger rock, high-conductivity cracks). Two other parameters are likely to influence the velocity, namely TOC and the presence of gas in the porous network of the rock. When taking into account the influence of both depth and TOC, around 80 % of the studied wells follow a distinct pattern. When taking into account gas as a pore fluid, around half of the other studied wells follow the same trend.

Angeli, M.; Gabrielsen, R. H.; Faleide, J. I.

2012-04-01

138

Elastic parameters of rocks from well logging in near surface sediments  

NASA Astrophysics Data System (ADS)

Acoustic full waveforms recorded in wells are the simplest way to get the velocity of P, S, and Stoneley waves in situ. Processing and interpretation of acoustic full waveforms in hard formations does not generate problems with identification packets of waves and calculation of their slowness and arrivals, and determination of the elastic parameter of rocks. But in shallow intervals of wells, in soft formations, some difficulties arise with proper evaluation of the S-wave velocity due to the lack of refracted S wave in case when its velocity is lower than the velocity of mud. Dynamic approach to selection of a proper value of semblance to determine the proper slowness and arrival is presented. Correlation between the results obtained from the proposed approach and the theoretical modeling is a measure of the correctness of the method.

Jarzyna, Jadwiga; Ba?a, Maria; Cichy, Adam

2010-02-01

139

Design manual for a well-logging probe capable of measuring tritium  

SciTech Connect

The purpose of this instrument is to measure the concentration of tritium in situ in a well or bore hole. The instrument is designed to detect tritium at concentrations as low as terrestrial surface background. The instrument can sample air or water, and purify the sample from other radioactive nuclides and from chemical contaminants. The instrument will operate satisfactorily in the presence of a moderate gamma-ray background.

Menninga, C.; Brodzinski, R.L.

1981-10-01

140

Development and demonstration of an enhanced spreadsheet-based well log analysis software. Final report, May 1998  

SciTech Connect

The Advanced Class Work Program is a field-based research and demonstration program for demonstration of advanced or improved technologies identified in the Department of Energy`s Class Field Demonstration Projects. The objective of the Advanced Class Work program is to conduct field demonstrations of technologies for which a small, incremental amount of work will produce or improve a transferable, useful technology for oil recovery. The goal of the program is to enhance the products of near-term Class projects and maximize the applicability and effectiveness of project results. PfEFFER (Petrofacies Evaluation of Formations For Engineering Reservoirs) is a well log analysis computer package. The software was tested and successfully applied in Schaben Field, a DOE Class 2 Field Demonstration Project to assist in improving reservoir characterization and assessing reservoir performance. PfEFFER v.1 was released in January, 1996 as a commercial spreadsheet-based well-log analysis program developed and distributed through the Kansas Geological Survey. The objectives of this project were: Task 1 -- Enhance the PfEFFER software package; Task 2 -- Develop major new modules to significantly augment PfEFFER capabilities; Task 3 -- Conduct field demonstration of software application using the necessary reservoir data acquired from oil operators and construct a database; and Task 4 -- Perform technology transfer activities that include workshops, reports, presentations, or other methods to communicate results to interested parties.

Watney, W.L.; Doveton, J.H.; Guy, W.J.

1998-10-01

141

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

142

Evidence of gas hydrate accumulation and its resource estimation in Andaman deep water basin from seismic and well log data  

NASA Astrophysics Data System (ADS)

2D and 3D seismic reflection and well log data from Andaman deep water basin are analyzed to investigate geophysical evidence related to gas hydrate accumulation and saturation. Analysis of seismic data reveals the presence of a bottom simulating reflector (BSR) in the area showing all the characteristics of a classical BSR associated with gas hydrate accumulation. Double BSRs are also observed on some seismic sections of area (Area B) that suggest substantial changes in pressure-temperature (P-T) conditions in the past. The manifestation of changes in P-T conditions can also be marked by the varying gas hydrate stability zone thickness (200-650 m) in the area. The 3D seismic data of Area B located in the ponded fill, west of Alcock Rise has been pre-stack depth migrated. A significant velocity inversion across the BSR (1,950-1,650 m/s) has been observed on the velocity model obtained from pre-stack depth migration. The areas with low velocity of the order of 1,450 m/s below the BSR and high amplitudes indicate presence of dissociated or free gas beneath the hydrate layer. The amplitude variation with offset analysis of BSR depicts increase in amplitude with offset, a similar trend as observed for the BSR associated with the gas hydrate accumulations. The presence of gas hydrate shown by logging results from a drilled well for hydrocarbon exploration in Area B, where gas hydrate deposit was predicted from seismic evidence, validate our findings. The base of the hydrate layer derived from the resistivity and acoustic transit-time logs is in agreement with the depth of hydrate layer interpreted from the pre-stack depth migrated seismic section. The resistivity and acoustic transit-time logs indicate 30-m-thick hydrate layer at the depth interval of 1,865-1,895 m with 30 % hydrate saturation. The total hydrate bound gas in Area B is estimated to be 1.8 × 1010 m3, which is comparable (by volume) to the reserves in major conventional gas fields.

Prakash, Anand; Samanta, B. G.; Singh, N. P.

2013-03-01

143

MS-BWME: A Wireless Real-Time Monitoring System for Brine Well Mining Equipment.  

PubMed

This paper describes a wireless real-time monitoring system (MS-BWME) to monitor the running state of pumps equipment in brine well mining and prevent potential failures that may produce unexpected interruptions with severe consequences. MS-BWME consists of two units: the ZigBee Wireless Sensors Network (WSN) unit and the real-time remote monitoring unit. MS-BWME was implemented and tested in sampled brine wells mining in Qinghai Province and four kinds of indicators were selected to evaluate the performance of the MS-BWME, i.e., sensor calibration, the system's real-time data reception, Received Signal Strength Indicator (RSSI) and sensor node lifetime. The results show that MS-BWME can accurately judge the running state of the pump equipment by acquiring and transmitting the real-time voltage and electric current data of the equipment from the spot and provide real-time decision support aid to help workers overhaul the equipment in a timely manner and resolve failures that might produce unexpected production down-time. The MS-BWME can also be extended to a wide range of equipment monitoring applications. PMID:25340455

Xiao, Xinqing; Zhu, Tianyu; Qi, Lin; Moga, Liliana Mihaela; Zhang, Xiaoshuan

2014-01-01

144

MS-BWME: A Wireless Real-Time Monitoring System for Brine Well Mining Equipment  

PubMed Central

This paper describes a wireless real-time monitoring system (MS-BWME) to monitor the running state of pumps equipment in brine well mining and prevent potential failures that may produce unexpected interruptions with severe consequences. MS-BWME consists of two units: the ZigBee Wireless Sensors Network (WSN) unit and the real-time remote monitoring unit. MS-BWME was implemented and tested in sampled brine wells mining in Qinghai Province and four kinds of indicators were selected to evaluate the performance of the MS-BWME, i.e., sensor calibration, the system's real-time data reception, Received Signal Strength Indicator (RSSI) and sensor node lifetime. The results show that MS-BWME can accurately judge the running state of the pump equipment by acquiring and transmitting the real-time voltage and electric current data of the equipment from the spot and provide real-time decision support aid to help workers overhaul the equipment in a timely manner and resolve failures that might produce unexpected production down-time. The MS-BWME can also be extended to a wide range of equipment monitoring applications. PMID:25340455

Xiao, Xinqing; Zhu, Tianyu; Qi, Lin; Moga, Liliana Mihaela; Zhang, Xiaoshuan

2014-01-01

145

Synchronization of Well Log Data and Geophysical Data with Remote Sensing Technique to Develop the Hydrocarbon System of Bengal Basin  

NASA Astrophysics Data System (ADS)

Remote sensing along with more conventional exploration techniques such as geophysics and reconnaissance field mapping can help to establish regional geologic relationships, to extract major structural features and to pinpoint anomalous patterns. Many well have been drilled in Bengal basin still no commercially viable reserves have been discovered. Geophysical well logging is used in virtually every oil well. It is the primary means by which we characterize the subsurface in search of hydrocarbons. Oil and gas exploration activities for large areas require ground gravity surveys to facilitate detailed geological interpretations for subsurface features integrating geological cross-sections with the sub-surface structural trends leads to the identification of prospect areas. Remote sensing, geological and geophysical data integration provide accurate geometric shapes of the basins. Bengal basin has a sedimentary fill of 10-15 km, is the northernmost of the east coast basins of India In the first phase Remote sensing satellite sensors help in identifying surface anomaly which indicates the presence of hydrocarbon reservoirs providing regional geological settings of petroleferous basins. It provides accurate and visual data for directly determining geometric shapes of basin. It assists in the selection of exploration regions by defining the existence of sedimentary basin. Remote sensing methods can generate a wealth of information useful in determining the value of exploratory prospecting. In the second phase Well Log data provide relative subsurface information for oil and gas exploration. Remote sensing data are merged with other available information such as Aeromagnetic, gravity, geochemical surveys and 2D seismic surveys. The result of this phase is to estimate the outcome of oil discovery probabilities for locating oil prospects

Kesh, S.; Samadder, P. K.

2012-12-01

146

Recent and pre-instrumental climatic conditions as reconstructed from temperature logs in wells in western and northern Canada  

SciTech Connect

This study reports a subregional analysis of ground surface temperature (GST) and surface air temperature (SAT) in Canada. Temperature logs made to depths of up to 300 m in 80 wells in the Canadian Prairie Provinces were compared with SAT in this area. A statistically significant spatial correlation was found between identical grid samples extracted from the 1950-1990 warming maps for SAT and GST warming. The results of modelling of precise temperature logs show evidence of annual warming of GST over the past half century of 2.1 C with a standard deviation of 0.9C. Annual SAT warming in this region for the same period, as derived from historical climatological records, has been 1.5C with a standard deviation of 0.4C. The difference between GST and SAT warming has been close to 40% in the boreal forest ecozone of northern Alberta and less than 10% in the prairie grassland ecozone of southern Alberta. It is hypothesized that a large portion of GST warming is a result of accelerating natural and anthropogenic land clearing through deforestation and farming. If the rate of climatic warming and anthropogenic change to the land surface continues, the southern boundary of the discontinuous permafrost will move northward at a faster rate than predicted from instrumental SAT warming data alone. 21 refs., 7 figs.

Majorowicz, J.A. [Northern Geothermal, Edmonton, Alberta (Canada); Skinner, W.R. [Environment Canada, Toronto, Ontario (Canada)

1997-11-01

147

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

148

Interpretation of core and well log physical property data from drill hole UPH-3, Stephenson County, Illinois  

USGS Publications Warehouse

Laboratory and well log physical property measurements show variations in the mineralogy with depth in UPH-3. Gamma ray values generally decrease with depth in the drill hole, corresponding to a decrease in the felsic mineral components of the granite. Correspondingly, an increase with depth in mafic minerals in the granite is indicated by the magnetic susceptibility, and gamma ray measurements. These mineralogic changes indicated by the geophysical well logs support the hypothesis of fractionation during continuous crystallization of the intrusive penetrated by UPH-3. Two fracture zones, and an altered zone within the granite penetrated by drill hole UPH-3 are defined by the physical property measurements. An abnormally low magnetic susceptibility response in the upper portion of the drill hole can be attributed to alteration of the rock adjacent to the sediments overlying the granite. Fracture zones can be identified from the sonic velocity, neutron, and resistivity measurements. A fracture zone, characterized by low resistivity values and low neutron values, is present in the depth interval from 1150 to 1320 m. Low magnetic susceptibility and high gamma ray values indicate the presence of felsic-micaceous pegmatites within this fracture zone. An unfractured region present from a depth of 1380 m to the bottom of the hole is characterized by an absence of physical property variations. The magnetic susceptibility and gamma ray measurements indicate a change in the amount of mafic minerals at the base of this otherwise homogenous region of the drilled interval. Abrupt changes and repeated patterns of physical properties within the drill hole may represent interruptions in the crystallization process of the melt or they may be indicative of critical temperatures for specific mineral assemblages within the intrusive.

Daniels, J. J.; Olhoeft, G. R.; Scott, J. H.

1984-01-01

149

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

150

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 Sønderborg 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

151

Geochemical and well-log investigation of an actively generating source rock sequence: Waltman shale, Wind River basin, Wyoming  

SciTech Connect

The Waltman Shale Member of the Fort Union Formation is a thick lacustrine shale deposited in the Wind River basin during Paleocene time. Available geologic and geophysical data suggest that the depositional conditions were relatively constant during deposition. These data also indicate that Lake Waltman was deep, with maximum water depths on the order of 500 ft. Sonic logs indicate that within deeper portions of the basin a velocity inversion is seen in the Waltman Shale Member, where the expected increase in acoustic velocity with depth due to compaction is not observed. An examination of available data reveals that this anomaly does not appear to be a result of either differences in organic matter content or mineralogy. The inversion appears to be most likely the result of overpressuring within the unit. The pyrolysis data indicate that the overpressuring within the unit. The pyrolysis data indicate that the overpressuring is associated with hydrocarbon generation and the inability of the system to effectively expel these hydrocarbons through a massive shale. The proposed relationship among the acoustic inversion, overpressuring, and active hydrocarbon generation is supported by the disappearance of the acoustic anomaly and the anomalous free hydrocarbon content in the vicinity of sand layers in some of the wells examined. These sands allow for the expulsion or drainage of hydrocarbons from the shale and a return to normal pressures and a normal seismic velocity profile.

Jorjorian, T.; Liro, L.M.; Katz, B.J. (Texaco Inc., Houston, TX (USA))

1989-09-01

152

Electrofacies in gas shale from well log data via cluster analysis: A case study of the Perth Basin, Western Australia  

NASA Astrophysics Data System (ADS)

Identifying reservoir electrofacies has an important role in determining hydrocarbon bearing intervals. In this study, electrofacies of the Kockatea Formation in the Perth Basin were determined via cluster analysis. In this method, distance data were initially calculated and then connected spatially by using a linkage function. The dendrogram function was used to extract the cluster tree for formations over the study area. Input logs were sonic log (DT), gamma ray log (GR), resistivity log (IND), and spontaneous potential (SP). A total of 30 reservoir electrofacies were identified within this formation. Integrated geochemical and petrophysics data showed that zones with electrofacies 3, 4, 9, and 10 have potential for shale gas production. In addition, the results showed that cluster analysis is a precise, rapid, and cost-effective method for zoning reservoirs and determining electrofacies in hydrocarbon reservoirs.

Torghabeh, Amir Karimian; Rezaee, Reza; Moussavi-Harami, Reza; Pradhan, Biswajeet; Kamali, Mohammad Reza; Kadkhodaie-Ilkhchi, Ali

2014-09-01

153

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

154

Comparison of Nuclear Magnetic Resonance (NMR) Logs to Hydraulic Tests in Wells Completed in Glacial Sediments in New England  

NASA Astrophysics Data System (ADS)

Borehole nuclear magnetic resonance (NMR) logs provide depth-dependent estimates of porosity, saturation, mobile and immobile water fraction, and estimates of permeability, all of which are aquifer properties important in groundwater-resource and contamination investigations. NMR tools, which have been widely used in the oil and gas industry for reservoir evaluation, recently have been designed for small-diameter boreholes typically used in groundwater investigations. In 2010 and 2011, the U.S. Geological Survey, in cooperation with Vista Clara, Inc., evaluated borehole NMR logging tools with diameters of 44 and 89 mm. The NMR logging was conducted in New England as the beginning phase of a national method development and demonstration effort. NMR logs were collected in boreholes completed in glacial sediments with interbedded layers of sand, silt, and gravel. The boreholes are less than 100-m deep and are cased with 2- or 4-inch diameter PVC. Estimates of bound water, free water, and total water content were determined from the distribution of transverse relaxation time at discrete vertical intervals of 1.0 m and 0.5 m, depending on which tool was used. Permeability was estimated empirically using the porosity and relaxation time. In this investigation, we compare NMR-derived estimates of water content and permeability to results of hydraulic testing and demonstrate the usefulness of NMR logging for obtaining in situ estimates of aquifer properties.

Johnson, C. D.; Lane, J. W.; LeBlanc, D. R.; Walsh, D. O.

2011-12-01

155

Chapter 9 -Irrigation Equipment Safety The following suggestions are aimed at ensuring the safety of the irrigator as well as  

E-print Network

141 Chapter 9 - Irrigation Equipment Safety The following suggestions are aimed at ensuring the safety of the irrigator as well as preventing damage to his equipment. 1. Read and follow directions. Disconnect electric power before servicing a machine by personally shutting off and locking the master

156

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

157

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

Microsoft Academic Search

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

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

2010-01-01

158

State-Of-The-Art in Permeability Determination From Well Log Data: Part 2-Verifiable, Accurate Permeability Predictions, the Touch-Stone of All Models  

E-print Network

SPE 30979 State-Of-The-Art in Permeability Determination From Well Log Data: Part 2- Verifiable Virginia University Copyright 1995, Society of Petroleum Engineers, Inc. This paper was prepared by the Society of Petroleum Engineers and are subject to correction by the author(s). Thematerial, as presented

Mohaghegh, Shahab

159

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

160

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

161

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

162

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

163

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

164

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

165

Study effects of geopressured-geothermal subsurface environment on elastic properties of Texas Gulf Coast sandstones and shales using well logs, core data, and velocity surveys. Final report  

SciTech Connect

Relations between porosity and permeability for the Pleasant Bayou wells were determined from conventional core data. Porosities from the time average equations required compaction correction factors of 1.9 in hydropressured sandstones and 1.0 in geopressured sandstones. Best average prmeabilities in the geopressured zone were found in the primary production interval 14,687 to 14,716 ft (4477 to 4485 m). Average density gradients were 2.106 x 10/sup -3/ and 2.688 x 10/sup -3/ (gm/cm/sup 3/)/100 ft in sandstones and shales respectively. Compressional (P-wave) and shear (S-wave) velocities from the long-spaced sonic log and bulk densities from the formation density log were used to compute in-situ elastic moduli, Poisson's ratio, V/sub p//V/sub s/, and bulk compressibility in two intervals of deep geopressured sandstone and shale in No. 2 Pleasant Bayou. Most computed values of these parameters seem reasonable. Improved accuracy of travel times from the long-spaced sonic log should permit more accurate depth-to-time correlation with seismic data.

Gregory, A.R.

1980-05-01

166

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

167

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

168

Velocity measurements in reservoir rock samples from a limestone unit using various pore fluids, and integration with well logs and seismic data  

NASA Astrophysics Data System (ADS)

One of the most promising methods proposed to mitigate excess global CO2 is carbon sequestration, a process in which CO2 is pressurized and injected into geologic formations. A technical challenge surrounding the geologic sequestration of CO2 is tracking the movement of the fluids pumped underground. Monitoring, verification and accounting activities related to CO2 storage are important for assuring that sequestered CO2 does not escape to the surface. Tracking this carbon dioxide can be considerably aided by reflection seismic-based detection methods. This thesis employs lab scale velocity measurements of core samples, under in situ reservoir pressure and temperature conditions, combined with multiple 3D reflection seismic surveys, to effectively track the movements of CO2 after injection. The National Energy Technology Laboratory (NETL) of the United States Department of Energy began to participate in research of an enhanced oil recovery project including the injection of CO2 deep into a reservoir structure, repeat reflection seismic surveys, collection of well logs, and rock physics analysis of sample core material. Our study is concentrated on a small area of this field around the injection site. At this site, hydrocarbons were previously moved via water injection. We obtained ultrasonic elastic wave velocity measurements that were conducted under several different saturation scenarios, including CO2 saturated samples, so a quantification of the conditions in different parts of the reservoir could be determined. This approach can help to characterize what is taking place inside the reservoir. Core-scale velocity measurements under in situ conditions allow us to predict changes in future well log or seismic surveys. The large amounts of CO2 accumulated over the past four decades in this reservoir give us a real world example of how an EOR site matures. Combining core scale, well log scale, and seismic scale measurements allows a better understanding of the various processes at work when CO2 is sequestered in a limestone reservoir.

Purcell, Christopher C.

169

Application of time-series analysis to induced gamma ray spectroscopy logs from two Cold Lake heavy-oil observation wells  

SciTech Connect

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 and the signal/noise characteristics of various IGRS log curves and to compute the coherence vs. spatial frequency of data collected on multiple IGRS passes. The coherence function ranges from 1.0 for perfect repeatability to 0.0 for incoherent noise. Because no real variations in the measured data were expected for the 12- to 24-hour data-collection period, andy deviation of the coherence function from 1.0 is attributed to incoherent noise. Generally, coherence is high at low frequencies (large vertical scales) and low at high frequencies (small vertical scales). By noting the frequency at which the coherence level decreases to the expected value of random noise, we can quantify the vertical resolution of a log curve. Data analysis from these wells indicates that both the vertical resolution and repeatability of individual capture and inelastic curves differ. We found that the H-yield and capture curves have the highest vertical resolution ({approx}0.3m) and the best signal/noise ratios (F{sub SN} {approx} 30:1). In contrast, the capture Ca and Si yields are of significantly lower quality (F{sub SN} {approx}2:1). Only a small difference exist between the vertical resolution of the inelastic C (1.0 m) and O (1.3 m) yields, but the F{sub SN} of the O yield is only one-half that of the C yield. Fortunately, the vertical resolution and the repeatability of the C/O ratio, F{sub CO}, are determined primarily by the quality of the inelastic C data.

Georgi, D.T. (Esso Resources Canada Ltd. (CA))

1991-12-01

170

Field project to obtain pressure core, wireline log, and production test data for evaluation of CO/sub 2/ flooding potential. Conoco MCA unit well No. 358, Maljamar Field, Lea County, New Mexico. Final report  

SciTech Connect

Field operations, which were conducted as a cooperative effort between Conoco and Gruy Federal, began on January 16, 1980 when the well was spudded. The well was drilled to 3692 feet, and 18 cores recovered in 18 core-barrel runs (144 feet). Upon completion of the coring phase, the hole was drilled to a total depth of 4150 feet and a complete suite of geophysical logs was run. Logging was then followed by completion and testing by Concoco. Core porosities agreed well with computed log porosities. Core water saturation and computed log porosities agree fairly well from 3692 to 3712 feet, poorly from 3712 to 3820 feet and in a general way from 4035 to 4107 feet. Computer log analysis techniques did not improve the agreement of log versus core derived water saturations. However, both core and log analysis indicated the ninth zone had the highest residual hydrocarbon saturations. Residual oil saturation were 259 STB/acre-ft for the 4035 - 4055 feet interval, and 150 STB/acre-ft for the 3692 - 3718 feet interval. Nine BOPD was produced from the 4035 - 4055 feet interval and no oil was produced from 3692 to 3718 feet interval, qualitatively confirming the relative oil saturations. The low oil production in the zone from 4022 to 4055 and the lack of production from 3692 to 3718 feet indicated the zone to be at or near residual waterflood conditions as determined by log analysis. 68 figures, 11 tables.

Swift, T.E.; Kumar, R.M.; Marlow, R.E.; Wilhelm, M.H.

1982-08-01

171

The thermal regime in the resurgent dome of Long Valley Caldera, California: Inferences from precision temperature logs in deep wells  

USGS Publications Warehouse

Long Valley Caldera in eastern California formed 0.76Ma ago in a cataclysmic eruption that resulted in the deposition of 600km3 of Bishop Tuff. The total current heat flow from the caldera floor is estimated to be ~290MW, and a geothermal power plant in Casa Diablo on the flanks of the resurgent dome (RD) generates ~40MWe. The RD in the center of the caldera was uplifted by ~80cm between 1980 and 1999 and was explained by most models as a response to magma intrusion into the shallow crust. This unrest has led to extensive research on geothermal resources and volcanic hazards in the caldera. Here we present results from precise, high-resolution, temperature-depth profiles in five deep boreholes (327-1,158m) on the RD to assess its thermal state, and more specifically 1) to provide bounds on the advective heat transport as a guide for future geothermal exploration, 2) to provide constraints on the occurrence of magma at shallow crustal depths, and 3) to provide a baseline for future transient thermal phenomena in response to large earthquakes, volcanic activity, or geothermal production. The temperature profiles display substantial non-linearity within each profile and variability between the different profiles. All profiles display significant temperature reversals with depth and temperature gradients <50??C/km at their bottom. The maximum temperature in the individual boreholes ranges between 124.7??C and 129.5??C and bottom hole temperatures range between 99.4??C and 129.5??C. The high-temperature units in the three Fumarole Valley boreholes are at the approximate same elevation as the high-temperature unit in borehole M-1 in Casa Diablo indicating lateral or sub-lateral hydrothermal flow through the resurgent dome. Small differences in temperature between measurements in consecutive years in three of the wells suggest slow cooling of the shallow hydrothermal flow system. By matching theoretical curves to segments of the measured temperature profiles, we calculate horizontal groundwater velocities in the hydrothermal flow unit under the RD that range from 1.9 to 2.8m/yr, which corresponds to a maximum power flowing through the RD of 3-4MW. The relatively low temperatures and large isothermal segments at the bottom of the temperature profiles are inconsistent with the presence of magma at shallow crustal levels. ?? 2010.

Hurwitz, S.; Farrar, C. D.; Williams, C. F.

2010-01-01

172

The thermal regime in the resurgent dome of Long Valley Caldera, California: Inferences from precision temperature logs in deep wells  

NASA Astrophysics Data System (ADS)

Long Valley Caldera in eastern California formed 0.76 Ma ago in a cataclysmic eruption that resulted in the deposition of 600 km 3 of Bishop Tuff. The total current heat flow from the caldera floor is estimated to be ~ 290 MW, and a geothermal power plant in Casa Diablo on the flanks of the resurgent dome (RD) generates ~40 MWe. The RD in the center of the caldera was uplifted by ~ 80 cm between 1980 and 1999 and was explained by most models as a response to magma intrusion into the shallow crust. This unrest has led to extensive research on geothermal resources and volcanic hazards in the caldera. Here we present results from precise, high-resolution, temperature-depth profiles in five deep boreholes (327-1,158 m) on the RD to assess its thermal state, and more specifically 1) to provide bounds on the advective heat transport as a guide for future geothermal exploration, 2) to provide constraints on the occurrence of magma at shallow crustal depths, and 3) to provide a baseline for future transient thermal phenomena in response to large earthquakes, volcanic activity, or geothermal production. The temperature profiles display substantial non-linearity within each profile and variability between the different profiles. All profiles display significant temperature reversals with depth and temperature gradients <50 °C/km at their bottom. The maximum temperature in the individual boreholes ranges between 124.7 °C and 129.5 °C and bottom hole temperatures range between 99.4 °C and 129.5 °C. The high-temperature units in the three Fumarole Valley boreholes are at the approximate same elevation as the high-temperature unit in borehole M-1 in Casa Diablo indicating lateral or sub-lateral hydrothermal flow through the resurgent dome. Small differences in temperature between measurements in consecutive years in three of the wells suggest slow cooling of the shallow hydrothermal flow system. By matching theoretical curves to segments of the measured temperature profiles, we calculate horizontal groundwater velocities in the hydrothermal flow unit under the RD that range from 1.9 to 2.8 m/yr, which corresponds to a maximum power flowing through the RD of 3-4 MW. The relatively low temperatures and large isothermal segments at the bottom of the temperature profiles are inconsistent with the presence of magma at shallow crustal levels.

Hurwitz, Shaul; Farrar, Christopher D.; Williams, Colin F.

2010-12-01

173

Depositional Model for the Middle Eocene Oberlin Sand in Northwest Oberlin Field and Adjacent Areas, Allen Parish, Louisiana: A Well-log and Seismic Analysis  

NASA Astrophysics Data System (ADS)

The depositional environment of the middle to late Eocene Oberlin sand of Northwest Oberlin Field and Pilgrim Church Field in central Allen Parish, Louisiana, was investigated. The depositional environment of the Oberlin sand has been interpreted from observations of spontaneous potential log signatures, conventional core reports, paleontological reports, shape of isochore maps, coherency extraction attribute, amplitude extraction attribute, and multiple seismic and subsurface cross sections. Focus is centered on the juxtaposition of component sand bodies and their proximity to the interdistributary and prodelta environments. Sand bodies include distributary channels, distributary mouth bars, crevasse subdeltas and shelfal bars and are interpreted to be the products of lower deltaic and shelf processes. The results of this study are based on seismic analysis, display techniques and subsurface maps calibrated to well logs, models, and recognition criteria of modern and ancient depositional environments previously described in the regional literature. The integration of all available data provides an objective and systematic approach detailing the origin, lateral extent, geometry and architecture of the Oberlin sand in the lower deltaic plain and shelf environments. The results of this study may be applicable to similar age sands on trend with the study area. Understanding of sand component types of the lower deltaic and shelf environments is vital to exploration success and development optimization of hydrocarbon bearing reservoirs.

McVey, Timothy Keith

174

SHALLOW GEOTHERMAL ENERGY ACROSS CANADA AS DERIVED FROM WELL TEMPERATURE LOGS AND SURFACE AIR TEMPERATURE TIME SERIES SHOWS GAINS DUE TO RECENT WARMING  

NASA Astrophysics Data System (ADS)

Temperature data for Canada compiled from precise temperature logs in equilibrium wells, and temperature time series from a network of meteorological stations, allow calculation of the available heat energy for heating in the cold period and cooling in peak warm months. Surface air temperature (SAT) and subsurface temperature patterns down to -250m are constructed for Canada. Subsurface temperature logs were reduced to construct ground surface temperature (GST) maps. On average, the ground temperature values for southern Canada (above 0°C) are higher than the mean annual SAT, although the north-south gradient appears similar. We speculate that it may be related to external forcings such as variations in snow cover, solar radiation, and surface moisture flux. Winter and summer SAT normal (1971-2000) patterns were also analyzed with respect to the GST patterns. In Canada, south of the permanent permafrost border, the integrated value of potentially available heat energy during the heating season is 1.1.E21 Joules (1100 quads) in the upper 50m where temperatures 10-12°C are common in southern Canada. Temperatures as high as 14-18 oC are attained at -250m. Temperature gradients in the upper 200m are small due to recent climatic warming.

Majorowicz, J. A.; Skinner, W.; Safanda, J.; Grasby, S.

2009-12-01

175

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

176

Spin dynamics of Carr-Purcell-Meiboom-Gill-like sequences in grossly inhomogeneous B(0) and B(1) fields and application to NMR well logging.  

PubMed

The spin dynamics for Carr-Purcell-Meiboom-Gill-like sequences is analyzed in grossly inhomogeneous B(0) and B(1) 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(-1)(1) and T(-1)(2). 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 B(0) and B(1) field maps. PMID:10698653

Hürlimann, M D; Griffin, D D

2000-03-01

177

Modeling and analysis of stick-slip and bit bounce in oil well drillstrings equipped with drag bits  

NASA Astrophysics Data System (ADS)

Rotary drilling systems equipped with drag bits or fixed cutter bits (also called PDC), used for drilling deep boreholes for the production and the exploration of oil and natural gas, often suffer from severe vibrations. These vibrations are detrimental to the bit and the drillstring causing different failures of equipment (e.g., twist-off, abrasive wear of tubulars, bit damage), and inefficiencies in the drilling operation (reduction of the rate of penetration (ROP)). Despite extensive research conducted in the last several decades, there is still a need to develop a consistent model that adequately captures all phenomena related to drillstring vibrations such as nonlinear cutting and friction forces at the bit/rock formation interface, drive system characteristics and coupling between various motions. In this work, a physically consistent nonlinear model for the axial and torsional motions of a rotating drillstring equipped with a drag bit is proposed. A more realistic cutting and contact model is used to represent bit/rock formation interaction at the bit. The dynamics of both drive systems for rotary and translational motions of the drillstring, including the hoisting system are also considered. In this model, the rotational and translational motions of the bit are obtained as a result of the overall dynamic behavior rather than prescribed functions or constants. The dynamic behavior predicted by the proposed model qualitatively agree well with field observations and published theoretical results. The effects of various operational parameters on the dynamic behavior are investigated with the objective of achieving a smooth and efficient drilling. The results show that with proper choice of operational parameters, it may be possible to minimize the effects of stick-slip and bit-bounce and increase the ROP. Therefore, it is expected that the results will help reduce the time spent in drilling process and costs incurred due to severe vibrations and consequent damage to equipment.

Kamel, Jasem M.; Yigit, Ahmet S.

2014-12-01

178

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

179

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

USGS Publications Warehouse

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.

2010-01-01

180

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

181

Borehole geophysical logging and aquifer-isolation tests conducted in well MG-1693 at North Penn Area 5 Superfund Site near Colmar, Montgomery County, Pennsylvania  

USGS Publications Warehouse

Borehole geophysical logging and aquifer-isolation (packer) tests were conducted in well MG-1693 (NP-87) at the North Penn Area 5 Superfund Site near Colmar, Montgomery County, Pa. Objectives of the study were to identify the depth and yield of water-bearing zones, occurrence of vertical borehole flow, and effects of pumping on water levels in nearby wells. Caliper, natural-gamma, single-point-resistance, fluid-temperature, fluid-resistivity, heatpulse-flowmeter, and borehole-video logs were collected. Vertical borehole-fluid movement direction and rate were measured under nonpumping conditions. The suite of logs was used to locate water-bearing fractures, determine zones of vertical borehole-fluid movement, and select depths to set packers. Aquifer-isolation tests were conducted to sample discrete intervals and to determine specific capacities of water-bearing zones and effects of pumping individual zones on water levels in two nearby monitor wells. Specific capacities of isolated zones during aquifer-isolation tests ranged from 0.03 to 3.09 (gal/min)/ft (gallons per minute per foot). Fractures identified by borehole geophysical methods as water-producing or water-receiving zones produced water when isolated and pumped. Water enters the borehole primarily through high-angle fractures at 416 to 435 ft bls (feet below land surface) and 129 to 136 ft bls. Water exits the borehole through a high-angle fracture at 104 to 107 ft bls, a broken casing joint at 82 ft bls, and sometimes as artesian flow through the top of the well. Thirteen intervals were selected for aquifer-isolation testing, using a straddle-packer assembly. The specific capacity of interval 1 was 2.09 (gal/min)/ft. The specific capacities of intervals 2, 3, and 4 were similar: 0.27, 0.30, and 0.29 (gal/min)/ft,respectively. The specific capacities of intervals 5, 6, 7, 8, and 10 were similar: 0.03, 0.04, 0.09, 0.09, and 0.04 (gal/min)/ft,respectively. Intervals 9, 11, and 12 each showed a strong hydraulic connection outside the borehole with intervals above and below the isolated interval. The specific capacities of intervals 9, 11, 12, and 13 were similar: 2.12, 2.17, 3.09, and 3.08 (gal/min)/ft, respectively. The aquifer-isolation tests indicate that wells MG-1693 (NP-87) and MG-924 (NP-21) are connected primarily through the high-angle fracture from 416 to 435 ft bls. Pumping in either of these wells directly impacts the other well, allowing the pumped well to draw from water-bearing zones in the non-pumped well that are not present in or are not connected directly to the pumped well. The two boreholes act as a single, U-shaped well. The aquifer-isolation tests also show that the lower zones in well MG-1693 (NP-87) are a major source of hydraulic head in well MG-1661 (W-13) through the broken casing joint at 82 ft bls. Water moving upward from the lower intervals in well MG-1693 (NP-87) exits the borehole through the broken casing joint, moves upward outside the borehole, possibly around and (or) through a poor or damaged casing seal, and through the weathered zone above bedrock to well MG-1661 (W-13). Samples for volatile organic compounds (VOCs) were collected in nine isolated intervals. Six compounds were detected (1,1-dichloroethane, 1,1-dichloroethene, cis-1,2-dichloroethene, toluene, 1,1,1-trichloroethane, and trichloroethene (TCE)), and TCE was found in all nine isolated intervals. Intervals 4 (124-149 ft bls) and 6 (277-302 ft bls) had the highest total concentration of VOCs (6.66 and 6.2 micrograms per liter, respectively). Intervals 1 (68-93 ft bls) and 4 each had five compounds detected, which was the highest number of compounds detected. Interval 5 (252-277 ft bls) had the lowest total concentration of VOCs (0.08 microgram per liter) and the least number of VOCs detected (one). Detected compounds were not evenly distributed throughout the intervals. Contaminants were found in shallow, intermediate, and deep intervals and were associated with

Bird, Philip H.

2006-01-01

182

Dielectric well logging system with at least three transmitter coils and at least two receiver coils for determining resistivity and dielectric constant of a subsurface formation adjacent a fluid  

Microsoft Academic Search

A dielectric well logging apparatus is described for obtaining amplitude ratios and phase differences between electromagnetic wave energy signals which have passed different distances through a subsurface formation adjacent a well borehole, so that an analyst may determine resistivity and dielectric constants for the different distances of travel through the formation. The apparatus consists of: (a) sonde means for moving

P. T. Cox; R. A. Meador; R. G. Jr. Riedesel; K. D. Savage

1986-01-01

183

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

184

How Well Does Brazil's Environmental Law Work in Practice? Environmental Impact Assessment and the Case of the Itapiranga Private Sustainable Logging Plan.  

PubMed

/ The Itapiranga Sustainable Logging Plan provides an example of how Brazil's licensing system functions for logging companies in the state of Amazonas. Two questions need to be dealt with: "How sustainable can logging in the Amazon be?" and "What and how effective are existing legal mechanisms to deal with logging projects?" The environmental impact assessment (EIA) and environmental impact statement (EIS, known as the RIMA in Brazil), present relatively detailed accounts of biodiversity and the need to adopt conservation strategies to protect it. However, social and health impacts are only superficially addressed. The economic sustainability of the operation over multiple cycles is not demonstrated. The multidisciplinary teams responsible for the EIA and EIS (RIMA) reports are hired by the project proponent, an arrangement inherently carrying the risk of biasing the result. Logging reduces biodiversity, releases greenhouse gases and inflicts social and health costs. These impacts reduce the ability of Amazonian forests to provide environmental services and to supply food and livelihood security to local populations. The reports inflate positive effects such as employment: the estimated number of jobs was cut by more than half in a revision made after the EIA and EIS (RIMA) had been approved. Not only do the reports need to be more realistic in assessing both positive and negative consequences of proposed projects, but better means are needed to ensure that promised mitigatory measures are enforced in practice. Many of the lessons that can be drawn from the Itapiranga Plan are not unique to logging projects and apply to licensing of development activites generally in Brazil and elsewhere. PMID:10977880

Eve; Arguelles; Fearnside

2000-09-01

185

Overpressure prediction by mean total stress estimate using well logs for compressional environments with strike-slip or reverse faulting stress state  

E-print Network

by modifying Eaton�s pore-pressure equations, which require either resistivity or sonic log data. The method was tested in the Snorre Field in the Norwegian North Sea, where the field changes from strike-slip to reverse stress state. Eaton...

Ozkale, Aslihan

2007-04-25

186

Quantifying the Permeability Heterogeneity of Sandstone Reservoirs in Boonsville Field, Texas by Integrating Core, Well Log and 3D Seismic Data  

E-print Network

the reservoir heterogeneity levels, which can be used to characterize the intra-bed and inter-bed heterogeneity. Post-stack seismic inversion was conducted to produce the key attribute, acoustic impedance, for the calibration of log properties with seismic...

Song, Qian

2013-04-29

187

Intelligent approaches for prediction of compressional, shear and Stoneley wave velocities from conventional well log data: A case study from the Sarvak carbonate reservoir in the Abadan Plain (Southwestern Iran)  

Microsoft Academic Search

Compressional, shear and Stoneley wave velocities (Vp, Vs and Vst, respectively) are important reservoir characteristics that have many applications in petrophysical, geophysical and geomechanical studies. In this study Vp, Vs and Vst were predicted from well log data using genetic algorithms, fuzzy logic and neuro-fuzzy techniques in an Iranian carbonate reservoir (Sarvak Formation). A total of 3030 data points from

Mojtaba Rajabi; Bahman Bohloli; Esmaeil Gholampour Ahangar

2010-01-01

188

Joint stochastic inversion of 3D pre-stack seismic data and well logs for high-resolution reservoir characterization and petrophysical modeling: application to deepwater hydrocarbon reservoirs in the central Gulf of Mexico  

Microsoft Academic Search

Summary This paper describes a novel algorithm for the joint stochastic inversion of well logs and multiple angle stacks of migrated 3D pre-stack seismic data. The inversion algorithm is based on a Bayesian statistical search criterion implemented with fast Markov-Chain Monte Carlo updates. It implements a-priori measures of spatial correlation as well as specific geometrical properties of structural and stratigraphic

Arturo Contreras; Carlos Torres-Verdín; William Chesters; Knut Kvien; Fugro-Jason Rotterdam; Tim Fasnacht

2005-01-01

189

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

190

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  

Microsoft Academic Search

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

Carlos Torres-Verdin; Mrinal K. Sen

2004-01-01

191

Logging for carbon tetrachloride contamination  

SciTech Connect

Neutron activation logging systems were used to prospect for residual saturations of carbon tetrachloride contamination at a nuclear weapons production facility. Logging was performed in wells near a former disposal trench, where up to 30,000 l were discharged between 1955 and 1962. The majority of this contamination has not been accounted for. To test for the presence of chlorine, a geochemical logging system was use to record capture gamma-ray spectra.

Grau, J.A.; Ellis, D.V. [Schlumberger-Doll, Ridgefield, CT (United States); Lewis, R.E. [Battelle-Pacific Northwest Lab., Richland, WA (United States)] [and others

1995-12-31

192

Results of investigation at the Miravalles Geothermal Field, Costa Rica: Part 1, Well logging. Resultados de las investigaciones en el campo geotermico de Miravalles, Costa Rica: Parte 1, Registros de pozos  

SciTech Connect

The well-logging operations performed in the Miravalles Geothermal Field in Costa Rica were conducted during two separate field trips. The Phase I program provided the deployment of a suite of high-temperature borehole instruments, including the temperature/rabbit, fluid sampler, and three-arm caliper in Well PGM-3. These same tools were deployed in Well PGM-10 along with an additional survey run with a combination fluid velocity/temperature/pressure instrument used to measure thermodynamic properties under flowing well conditions. The Phase II program complemented Phase I with the suite of tools deployed in Wells PGM-5, PGM-11, and PGM-12. 4 refs., 25 figs., 1 tab.

Dennis, B.R.; Lawton, R.G.; Kolar, J.D.; Alvarado, A.

1989-03-01

193

New materials for fireplace logs  

NASA Technical Reports Server (NTRS)

Fibrous insulation and refractory concrete are used for logs as well as fireproof walls, incinerator bricks, planters, and roof shingles. Insulation is lighter and more shock resistant than fireclay. Lightweight slag bonded with refractory concrete serves as aggregrate.

Kieselback, D. J.; Smock, A. W.

1971-01-01

194

Preliminary geological interpretation and lithologic log of the exploratory geothermal test well (INEL-1), Idaho National Enginering Laboratory, eastern Snake River Plain, Idaho  

Microsoft Academic Search

A 10,365 ft (3159 m) geothermal test well was drilled in the spring of 1979 at the Idaho National Engineering Laboratory, eastern Snake River Plain, Idaho. The majority of rock types encountered in the borehole are of volcanic origin. An upper section above 2445 ft (745 m) consists of basaltic lava flows and interbedded sediments of alluvial, lacustrine, and volcanic

D. J. Doherty; L. A. McBroome; M. A. Kuntz

1979-01-01

195

Logs help approximate reservoir temperature  

SciTech Connect

Parameters have been studied to better understand and analytically describe temperature distribution in well bores. Some of these parameters include: fluid temperature behavior in the borehole during well tripping; BHT while drilling; temperature profile over the entire borehole; and determination of true formation temperature from geophysical wire line logging devices. The technique presented in this article corrects open hole log temperatures to true formation temperature.

Fertl, W.H.

1985-04-29

196

An Integrated Application of Neural Network and Markov Chain Techniques to Prediction of Lithofacies from Well Logs (Kansas Geological Survey Open File Report 2003-50)  

Microsoft Academic Search

The Permian Council Grove Group in the Panoma Field of southwest Kansas has yielded 80 x 109 meter3 of gas from approximately 2600 wells from a 60-meter interval at depths of 800-1,000 meters since its discovery in the 1960's. Initial gas saturation, production rates and cumulative production in the Panoma Field are controlled by the distribution of porosity and permeability

G. C. Bohling; M. K. Dubois

197

Intelligent approaches for prediction of compressional, shear and Stoneley wave velocities from conventional well log data: A case study from the Sarvak carbonate reservoir in the Abadan Plain (Southwestern Iran)  

NASA Astrophysics Data System (ADS)

Compressional, shear and Stoneley wave velocities ( Vp, Vs and Vst, respectively) are important reservoir characteristics that have many applications in petrophysical, geophysical and geomechanical studies. In this study Vp, Vs and Vst were predicted from well log data using genetic algorithms, fuzzy logic and neuro-fuzzy techniques in an Iranian carbonate reservoir (Sarvak Formation). A total of 3030 data points from the Sarvak carbonate reservoir which have Vp, Vs, Vst and conventional well log data were used. These data were divided into two groups; one group included 2047 data points used for constructing intelligent models, and the other included 983 data points used for models testing. The measured mean squared errors (MSEs) of predicted Vp in the test data, using genetic algorithms, fuzzy logic and neuro-fuzzy techniques, were 0.0296, 0.0148 and 0.029, respectively, for Vs these errors were 0.0153, 0.0084 and 0.0184, respectively, and for Vst they were 0.00035, 0.00020 and 0.00062, respectively. Despite different concepts in these intelligent techniques, the results (especially those from fuzzy logic) seem to be reliable.

Rajabi, Mojtaba; Bohloli, Bahman; Gholampour Ahangar, Esmaeil

2010-05-01

198

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

199

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

200

Dipole shear anisotropy logging  

SciTech Connect

Sonic-scale shear anisotropy of formations are obtained from dipole-shear measurements acquired by orthogonal source and receiver pairs. These measurements resemble miniature 4-component shear VSP surveys inside the borehole. Data from two orthogonal sources and an array of orthogonal receivers are processed providing three main logs; the fast and slow shear slownesses, and the fast shear polarization angle. Potential applications include: shale anisotropy for better seismic models, maximum stress and fracture/microcrack strike direction for horizontal well drilling and fracture height and azimuth determination in hydraulic fracturing.

Esmersoy, C.; Kane, M. [Schlumberger-Doll Research, Ridgefield, CT (United States); Koster, K.; Williams, M. [Amoco Production, Denver, CO (United States); Boyd, A. [GeoQuest, Aurora, CO (United States)

1994-12-31

201

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

202

Testing the controls on the seismic sequence stratigraphy of the Eocene-Oligocene boundary in Southern Iran with a Wheeler diagram derived from outcrops, seismic and well logs data  

NASA Astrophysics Data System (ADS)

In this study of Southern Iran the timing of the boundary between the Eocene to Oligo-Miocene sections was determined along with a better understanding of the accumulation of the Paleocene to Eocene sediments. This was established by generating Wheeler diagrams from local seismic, well log data and surface data. This boundary was found to be mainly erosional and the time gap between Eocene to Oligo-Miocene displayed by the Wheeler diagram suggests a "degradational vacuity" formed. Relative sea level changes were found to be responsible for the seaward progradational character of the Jahrum Formation sediments. Red sediments and an intraformational conglomerate overlie this erosional boundary between the Paleocene to the Eocene Jahrum Formation and the Oligo-Miocene Asmari Formation. Long-term lower frequency trends in both regional tectonic and global sea-level curves determined from the Paleocene-Eocene sediments of south Iran, when compared to the coastal plain sediments of US New Jersey and the global coastal onlap chart, suggest that contemporaneous eustastic signals in lower Eocene time produced matching sedimentary patterns. The results of the study recorded in this paper are intended to be used as the foundation of the study of petroleum related facies and petroleum system components (source, reservoir and seal rocks) in the Tertiary portion of sedimentary section.

Chehri, Amin; Kendall, Christopher; Ghadimvand, Nader Kohansal; Samadi, Latif

2014-12-01

203

Site attenuation with log-periodic antennas  

Microsoft Academic Search

Site attenuation measurements made with biconical antennas below 200 MHz are found to agree rather well with calculations based on point dipole antennas. The log-periodic dipole antennas used above 200 MHz differ more drastically than the biconical from an ideal point dipole. Discrepancies arising from the use of log-periodic antennas are examined, and a simple modification of the site attenuation

J. D. Gavenda

1993-01-01

204

Wideband, planar, log-periodic balun  

Microsoft Academic Search

This paper presents the design and performance characteristics of a new planar balun structure. The design is based on the log-periodic antenna theory. The design guidelines, as well as simulated and measured results are presented. It is shown that the new balun has greater than one octave bandwidth. The log-periodic balun will find applications in wireless communication circuits such as

Mahmoud Basraoui; S. N. Prasad

1998-01-01

205

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

206

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

207

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

208

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

209

Teff log g nHe Teff log g A  

E-print Network

#12;#12;B Teff log g nHe Teff log g nHe Teff + #12;#12;#12;#12;#12;#12;2 #12;+ #12;#12;Teff #12;+ °A + + #12;+ Teff log g °A log g - Teff log g - Teff #12;- + + + + log g - Teff #12;#12;Teff #12; 10 #12; 8 #12; 6 -2 4 3 8 9 � 10 #12;#12;g nHe n

210

40 CFR 63.424 - Standards: Equipment leaks.  

...leak inspection of all equipment in gasoline service. For this inspection, detection methods incorporating sight, sound, and smell are acceptable. Each piece of equipment shall be inspected during the loading of a gasoline cargo tank. (b) A log...

2014-07-01

211

40 CFR 63.424 - Standards: Equipment leaks.  

Code of Federal Regulations, 2013 CFR

...leak inspection of all equipment in gasoline service. For this inspection, detection methods incorporating sight, sound, and smell are acceptable. Each piece of equipment shall be inspected during the loading of a gasoline cargo tank. (b) A log...

2013-07-01

212

40 CFR 63.424 - Standards: Equipment leaks.  

Code of Federal Regulations, 2012 CFR

...leak inspection of all equipment in gasoline service. For this inspection, detection methods incorporating sight, sound, and smell are acceptable. Each piece of equipment shall be inspected during the loading of a gasoline cargo tank. (b) A log...

2012-07-01

213

40 CFR 63.424 - Standards: Equipment leaks.  

Code of Federal Regulations, 2011 CFR

...leak inspection of all equipment in gasoline service. For this inspection, detection methods incorporating sight, sound, and smell are acceptable. Each piece of equipment shall be inspected during the loading of a gasoline cargo tank. (b) A log...

2011-07-01

214

40 CFR 63.424 - Standards: Equipment leaks.  

Code of Federal Regulations, 2010 CFR

...leak inspection of all equipment in gasoline service. For this inspection, detection methods incorporating sight, sound, and smell are acceptable. Each piece of equipment shall be inspected during the loading of a gasoline cargo tank. (b) A log...

2010-07-01

215

Log periodic dipole arrays  

Microsoft Academic Search

A new class of coplanar dipole arrays is introduced. The antennas described provide unidirectional radiation patterns of constant beamwidth and nearly constant input impedances over any desired bandwidth. The broad-band properties are achieved by making use of the principles of log periodic antenna design. Models are discussed which are capable of providing 8- to 9-db directive gain with an associated

D. Isbell

1960-01-01

216

Log of Apollo 11.  

ERIC Educational Resources Information Center

The major events of the first manned moon landing mission, Apollo 11, are presented in chronological order from launch time until arrival of the astronauts aboard the U.S.S. Hornet. The log is descriptive, non-technical, and includes numerous color photographs of the astronauts on the moon. (PR)

National Aeronautics and Space Administration, Washington, DC.

217

,"_' ",',-i_~ :FORESTRY AND LOGGING  

E-print Network

":~I> ", .' '. ,"_' ",',-i_~ . :FORESTRY AND LOGGING Hcscarch on Plantation Species A Positive in plantation forestry. par- ticularly in the tropics and the Southern Hemisphere. in the past 30 years plantation forestry. Indeed, one could list many exam- ples of such problems that have plagued exotic

218

Internet Data logging and Display  

E-print Network

-OF-THE-ART Remotely located data loggers have been used extensively for collecting measurement data [2] [3] [4] [5] [6]. Convenient retrieval of the data from the data logging device has al- ways presented a problem [7] [8]. One solution, for ex- ample, takes... of the sample, (5) 64-bit 1-Wire ID of the sensor or device used to communicate with the sensor (this is stored as an array of 8 bytes, as well as the string representation of the ID), (6) description of the sen- sor, and (7) channel number (if the device has...

Sweeney, J., Jr.; Culp, C.; Haberl, J. S.

2001-01-01

219

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

220

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

221

University Equipment EQUIPMENT DISPOSAL FORM  

E-print Network

University Equipment EQUIPMENT DISPOSAL FORM Please return form to Financial Services Attn: Debt Asset (Tag) Number (please remove tag and attach) Description Original Cost (estimated) Acquisition Date Equipment Purchased on Federal Funds: By checking this box, I confirm this disposal complies

He, Chuan

222

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

223

Principle and geometric precision of photographic geological logging of tunnels  

NASA Astrophysics Data System (ADS)

Considering the problem of engineering geological logging technique by means of sketching at the work site, this paper presents a photographic geological logging technique based on photogrammetry as well as engineering geology. The principles, methods, and working process have been discussed, and the photographic geological logging precision of a tunnel and its estimation method have been researched. The theoretical and experimental analysis shows that the precision of the digital unfolded image map of tunnel automatically generated by the photographic geological logging method is sufficient for serving as the logging base map. Besides, the measurement precision of unfolded images or stereopairs meets the requirements of geological attitude measurement. The new technique of photographic geological logging proposed in this paper is expected to replace the current sketch way of engineering geological logging on site, with the operation mode converted from manual operation to computer-aided operation and informatized management.

Li, Hao; Zhang, Rong-Chun; Yang, Biao; Wu, Ming-Fei

2014-01-01

224

Information Security Office Logging Standard  

E-print Network

Information Security Office Logging Standard #12;Logging Standard 1 | P a g e Revision History Revision Date Revised By Summary of Revisions Section(s) / Page(s) Revised 6/01/2013 ISO Initial Release Pufahl, CISO Approved 6/01/2013 RMAC Risk Management Advisory Council Reviewed #12;Logging Standard 2 | P

Alpay, S. Pamir

225

Wave functions of log-periodic oscillators  

SciTech Connect

We use the Lewis and Riesenfeld invariant method [J. Math. Phys. 10, 1458 (1969)] and a unitary transformation to obtain the exact Schroedinger wave functions for time-dependent harmonic oscillators exhibiting log-periodic-type behavior. For each oscillator we calculate the quantum fluctuations in the coordinate and momentum as well as the quantum correlations between the coordinate and momentum. We observe that the oscillator with m=m{sub 0}t/t{sub 0} and {omega}={omega}{sub 0}t{sub 0}/t, which exhibits an exact log-periodic oscillation, behaves as the harmonic oscillator with m and {omega} constant.

Bessa, V.; Guedes, I. [Departamento de Fisica, Universidade Federal do Ceara, Campus do Pici, Fortaleza, CE 60455-760 (Brazil)

2011-06-15

226

Wavefunctios of log-periodic oscillators  

E-print Network

We use the Lewis and Riesenfeld invariant method [\\textit{J. Math. Phys.} \\textbf{10}, 1458 (1969)] and a unitary transformation to obtain the exact Schr\\"{o}dinger wave functions for time-dependent harmonic oscillators exhibiting log-periodic-type behavior. For each oscillator we calculate the quantum fluctuations in the coordinate and momentum as well as the quantum correlations between the coordinate and momentum. We observe that the oscillator with $m=m_0t/t_0$ and $\\omega= \\omega_0t_0/t$, which exhibits an exact log-periodic oscillation, behaves as the harmonic oscillator with $m$ and $\\omega$ constant.

Bessa, V; 10.1063/1.3601739

2012-01-01

227

Wave functions of log-periodic oscillators  

NASA Astrophysics Data System (ADS)

We use the Lewis and Riesenfeld invariant method [J. Math. Phys. 10, 1458 (1969)], 10.1063/1.1664991 and a unitary transformation to obtain the exact Schrödinger wave functions for time-dependent harmonic oscillators exhibiting log-periodic-type behavior. For each oscillator we calculate the quantum fluctuations in the coordinate and momentum as well as the quantum correlations between the coordinate and momentum. We observe that the oscillator with m = m0t/t0 and ? = ?0t0/t, which exhibits an exact log-periodic oscillation, behaves as the harmonic oscillator with m and ? constant.

Bessa, V.; Guedes, I.

2011-06-01

228

Borehole compensated KUT log  

SciTech Connect

A method of logging earth formations to ascertain relative elemental abundances of potassium (K), uranium (U) and thorium (T) is disclosed. A natural gamma ray spectrum of an unknown borehole is compared with individual standard gamma ray spectra of potassium, uranium and thorium in at least four energy ranges or bands. Decay peaks of the three elements are encompassed by three of the energy bands and at least one other energy band is used to monitor the changes in shape of the unknown spectrum caused by borehole conditions differing from that of the standard or calibration boreholes. A function derived from the gamma ray count rates in the four bands is used to compensate the elemental abundances of the three elements to be detected in the unknown spectrum for the effects of differing borehole conditions in the unknown borehole from the standard borehole conditions.

Arnold, D.M.; Schultz, W.E.; Smith, H.D. Jr.

1984-03-13

229

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

230

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

231

Terminology Extraction from Log Files  

NASA Astrophysics Data System (ADS)

The log files generated by digital systems can be used in management information systems as the source of important information on the condition of systems. However, log files are not exhaustively exploited in order to extract information. The classical methods of information extraction such as terminology extraction methods are irrelevant to this context because of the specific characteristics of log files like their heterogeneous structure, the special vocabulary and the fact that they do not respect a natural language grammar. In this paper, we introduce our approach Exterlog to extract the terminology from log files. We detail how it deals with the particularity of such textual data.

Saneifar, Hassan; Bonniol, Stéphane; Laurent, Anne; Poncelet, Pascal; Roche, Mathieu

232

G8 Illegal Logging Dialogue G8 Illegal Logging Dialogue  

E-print Network

representatives · agree practical policy actions to address illegal logging and sustainable forest management and sustainable forestry Reaching out to Chinese legislators China and the Global Forest Products Trade Trade governments #12;G8 Illegal Logging Dialogue · legislators from: ­ all G8 countries ­ Brazil ­ Cameroon ­ China

233

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

234

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

235

Chapter XXV Web Log Analysis  

E-print Network

504 Chapter XXV Web Log Analysis: Diversity Of Research Methodologies Isak Taksa City University these methodologies, and propose directions for future research in the field of Web log analysis. rEsEArcH MEtHODOLOGIEs of phenomenology, examines individual and group interactions within a social structure. · Content Analysis

Jansen, James

236

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

237

A practical approach to the interpretation of cement bond logs  

SciTech Connect

The Cement Bond Log has been controversial since its inception. Despite its potential, it is possibly the most maligned logging service available to the industry. Effective zone isolation between permeable intervals in a well requires a cement sheath over an appreciable vertical interval. It is necessary for the annular cement sheath to provide an effective hydraulic seal in order to withstand subsequent completion and production operations. The oil industry has used wireline well logs to detect the presence or absence of cement behind pipe for more than twenty years. Users have attempted, not always successfully, to evaluate the effectiveness of cement bond to both pipe and formation, ostensibly, with Cement Bond Logs. Cement Bond Logs do not mislead. Poor interpretation habits mislead. Knowledge of the well completion and the inherent physical restraints placed upon the log measurements is needed in order to properly evaluate the log. The purpose here is to dispel some of the myths created by misguided interpretation practices. Examples of Cement Bond Logs which fall into this category are presented.

Bigelow, E.L.

1985-03-01

238

A practical approach to the interpretation of cement bond logs  

SciTech Connect

The cement bond log has been controversial since its inception. Despite its potential, it is possibly the most maligned logging service available to the industry. Effective zone isolation between permeable intervals in a well requires a cement sheath over an appreciable vertical interval. It is necessary for the annular cement sheath to provide an effective hydraulic seal to withstand subsequent completion and production operations. The oil industry has used wireline well logs to detect the presence or absence of cement behind pipe for more than 20 years. Users have attempted, not always successfully, to evaluate the effectiveness of cement bond to both pipe and formation with cement bond logs. Cement bond logs do not mislead. Poor interpretation habits mislead. Knowledge of the well completion and the inherent physical restraints placed on the log measurements is needed to evaluate the log properly. The purpose here is to dispel some of the myths created by misguided interpretation practices. Examples of cement bond logs that fall into this category are be presented.

Bigelow, E.L.

1985-07-01

239

Method for making logging sleeve  

SciTech Connect

A method is described for making a logging sleeve adapted to slide on and off a drill string in a well for measuring a downhole characteristic in the well. The method includes the steps of: (a) placing at least one layer of resin-coated fibers in a longitudinal groove in a mandrel; (b) placing an elongated electrical conductor having an end on the resin-coated fibers in the groove; (c) placing additional resin-coated fibers on the conductor to substantially fill the groove; (d) wrapping resin-coated fibers around the mandrel to cover the fibers in the groove; (e) mounting an electrically conductive annular ring with a longitudinally extending anchor strip on the resin-coated fibers wrapped around the mandrel; (f) electrically connecting the end of the conductor to the ring; (g) wrapping additional resin-coated fibers around the mandrel and at least a portion of the strip; (h) curing the resin to form the sleeve with an inner and longitudinal spline adapted to make a sliding fit in a matching longitudinal groove in the drill string; and (i) sliding the sleeve off the mandrel.

More, H.S.; Koch, C.E.

1986-07-22

240

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

241

Well-log interpretation of carbonate reservoirs with bimodal porosity  

E-print Network

SSSSSSSS NSSSM SWOSMS SOSSSSSS SW~SMS sssssmN SSSSSSSS SSSASSM SSSSSSS SSSSSS SSSSSPSS SSSSSE1S SSSSSSHS SSSSSSSS SRQ maNmrmaa~~mraNUN ~rarINI mrUUN mrmrl UNlllmrarr&~amia 1~NIQ=~~a?alN ~ EnHnnRN HNIIII mraraN NIMrara lll~lllll SIR . l E~S %! a= ~N... SSSSSSSS NSSSM SWOSMS SOSSSSSS SW~SMS sssssmN SSSSSSSS SSSASSM SSSSSSS SSSSSS SSSSSPSS SSSSSE1S SSSSSSHS SSSSSSSS SRQ maNmrmaa~~mraNUN ~rarINI mrUUN mrmrl UNlllmrarr&~amia 1~NIQ=~~a?alN ~ EnHnnRN HNIIII mraraN NIMrara lll~lllll SIR . l E~S %! a= ~N...

Tandircioglu, Ahmet

2012-06-07

242

Method and apparatus for epithermal neutron porosity well logging  

Microsoft Academic Search

This patent describes a method for investigating the porosity of a subsurface earth formation surrounding a borehole. It comprises repetitively irradiating the borehole and earth formation with discrete bursts of high energy neutrons from a neutron source, which neutrons interact with nuclei of the materials in the borehole and the formation to produce therein populations of epithermal neutrons; detecting the

R. C. Hertzog; W. A. Loomis; P. Wraight

1991-01-01

243

10 CFR 39.13 - Specific licenses for well logging.  

Code of Federal Regulations, 2013 CFR

... 39.13 Section 39.13 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND...70.23 of this chapter for special nuclear material, as appropriate, and any special...shall identify the manufacturers and the model numbers of the leak test kits to be...

2013-01-01

244

10 CFR 39.13 - Specific licenses for well logging.  

Code of Federal Regulations, 2012 CFR

... 39.13 Section 39.13 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND...70.23 of this chapter for special nuclear material, as appropriate, and any special...shall identify the manufacturers and the model numbers of the leak test kits to be...

2012-01-01

245

10 CFR 39.13 - Specific licenses for well logging.  

Code of Federal Regulations, 2011 CFR

... 39.13 Section 39.13 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND...70.33 of this chapter for special nuclear material, as appropriate, and any special...shall identify the manufacturers and the model numbers of the leak test kits to be...

2011-01-01

246

10 CFR 39.13 - Specific licenses for well logging.  

Code of Federal Regulations, 2010 CFR

... 39.13 Section 39.13 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND...70.33 of this chapter for special nuclear material, as appropriate, and any special...shall identify the manufacturers and the model numbers of the leak test kits to be...

2010-01-01

247

46 CFR 154.1852 - Air breathing equipment.  

Code of Federal Regulations, 2010 CFR

46 Shipping 5 2010-10-01 2010-10-01...equipment. 154.1852 Section 154.1852 Shipping COAST GUARD, DEPARTMENT OF HOMELAND...The master shall enter in the vessel's log a record of the inspection required...

2010-10-01

248

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.

Cashman, Patricia

249

BSP versus LogP  

Microsoft Academic Search

.    A quantitative comparison of the BSP and LogP models of parallel computation is developed. We concentrate on a variant of\\u000a LogP that disallows the so-called stalling behavior, although issues surrounding the stalling phenomenon are also explored.\\u000a Very efficient cross simulations between the two models are derived, showing their substantial equivalence for algorithmic\\u000a design guided by asymptotic analysis. It

Gianfranco Bilardi; Andrea Pietracaprina; Geppino Pucci; Kieran T. Herley; Paul G. Spirakis

1999-01-01

250

Maintaining ecosystem function and services in logged tropical forests.  

PubMed

Vast expanses of tropical forests worldwide are being impacted by selective logging. We evaluate the environmental impacts of such logging and conclude that natural timber-production forests typically retain most of their biodiversity and associated ecosystem functions, as well as their carbon, climatic, and soil-hydrological ecosystem services. Unfortunately, the value of production forests is often overlooked, leaving them vulnerable to further degradation including post-logging clearing, fires, and hunting. Because logged tropical forests are extensive, functionally diverse, and provide many ecosystem services, efforts to expand their role in conservation strategies are urgently needed. Key priorities include improving harvest practices to reduce negative impacts on ecosystem functions and services, and preventing the rapid conversion and loss of logged forests. PMID:25092495

Edwards, David P; Tobias, Joseph A; Sheil, Douglas; Meijaard, Erik; Laurance, William F

2014-09-01

251

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

252

Annual Logging Symposium, June 3-6, 2007 JOINT INVERSION OF DENSITY AND RESISTIVITY LOGS FOR THE  

E-print Network

, Robert Terry, BP Copyright 2007, held jointly by the Society of Petrophysicists and Well Log Analysts of in-place hydrocarbon reserves. To gain better understanding of measurement behavior in interbedded

Torres-Verdín, Carlos

253

Rescue Equipment  

NASA Technical Reports Server (NTRS)

The Lifeshear cutter, a rescue tool for freeing accident victims from wreckage, was developed under the Clinton Administration's Technology Reinvestment Program. Prior cutting equipment was cumbersome and expensive; the new cutter is 50 percent lighter and 70 percent cheaper. The cutter is pyrotechnically-actuated, using a miniature version of the power cartridges used for separation devices on the Space Shuttle and other NASA spacecraft. Hi-Shear Technology Corporation developed the cutter with the Jet Propulsion Laboratory and input from the City of Torrance (California) Fire Department.

1995-01-01

254

APS logDaemon and client library  

SciTech Connect

This document serves as a User`s Manual and Reference for the logDaemon and client library. This package provides a general distributed message logging system. A logDaemon may be started anywhere on a subnet. A client which has linked in the client library is provided functions to open a connection to the logDaemon, log messages, and close the connection. The logDaemon maintains one or more log files (in simple ASCII or SDDS format) and an e-mail list based on specifications in a configuration file. Incoming messages are logged to the appropriate file and/or result in e-mail being sent.

Saunders, C.; Kowalkowski, J.

1995-12-13

255

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

256

Technetium generator log form.  

PubMed

Technetium generators are loaded with molybdenum-99 (99Mo), that has a 66-h half life and decays to technetium-99 m (9mTc). 99Tc with a single 140 keV gamma photon emission and a 6-h half life is an ideal isotope for nuclear medicine imaging. Many nuclear medicine units receive generators and use the 99Tc elution to label a variety of prepared chemical species for the majority of the studies they perform. Other options are receiving bulk 99mTc and doing the same tagging or getting unit doses of already labeled pharmaceuticals. Units using generators must meet requirements spelled out in regulations of the Nuclear Regulatory Commission, Title 10, CFR, parts 20, 35, and 71 as well as the Department of Transportation, Title 49, CFR, part 173. The form described in this paper was an attempt to get all of the required records for each individual generator on a single sheet of paper. PMID:11480855

Vernig, P G

2001-08-01

257

Logging in a computational steering environment  

Microsoft Academic Search

Logging of input and output variables is very useful in computational steering. In this paper we describe how we added logging functionality to a computational steering environment developed at CWI. We show how a 2D interface can be augmented with logging by using the third dimension for the display of the logged variables. The user specifies which graphical representations of

Jurriaan D. Mulder; Jarke J. van Wijk

1995-01-01

258

Integration of Geology, Rock-Physics, Logs, and Pre-stack Seismic for Reservoir Porosity Estimation  

E-print Network

The main objective of this paper is to obtain reservoir properties, such as porosity, both at the well locations and in the inter-well regions from seismic data and well logs. The seismic and well-log datasets are from an ...

Al Muhaidib, Abdulaziz

2011-01-01

259

Health & Wellness  

MedlinePLUS

... 2-Peer Forum Blog Resources Getting Help Links & Books Site Help Press Kit Library Frequently Asked Questions ... this topic. Choose a Related Resources Library Links & Books Forums 27880 reads Please Log in You must ...

260

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

261

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

262

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

263

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...

264

Hermes Changes Log Daniel Fitton  

E-print Network

change to support the new Client Agent feature: · Run-length decoding of Note images sent by ClientHermes Changes Log Daniel Fitton November 1, 2004 This document chronicles the changes made software components is deployed the changes and date are noted. Figure 1 graphically shows the deployment

Cheverst, Keith

265

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

266

Keep a "SLOG" (Sleep Log)  

NSDL National Science Digital Library

In this activity (1st on the page), learners keep a "SLOG" or Sleep Log to study their sleep patterns. Learners keep track of their sleep behavior and the dreams that they have each night on the "Dream Journal Worksheet" and "Sleep Journal Worksheet" included in this activity guide. This guide also includes twenty questions for learners to consider when recording and analyzing their dreams.

Chudler, Eric H.

2009-01-01

267

Geomicrobial Optical Logging Detectors (GOLD)  

Microsoft Academic Search

We will present concepts for downhole instrumentation that could be used in the Deep Underground Science and Engineering Laboratory (DUSEL). We envision optical borehole-logging instruments that could monitor bacterial concentration, mineralogy, aromatic organics, temperature and oxygen concentration, allowing for the in situ monitoring of time-dependent microbial and short-scale geologic processes and provide valuable in situ data on stratigraphy to supplement

N. E. Bramall; C. R. Stoker; P. B. Price; J. D. Coates; L. J. Allamandola; A. L. Mattioda

2008-01-01

268

Audit Log for Forensic Photography  

NASA Astrophysics Data System (ADS)

We propose an architecture for an audit log system for forensic photography, which ensures that the chain of evidence of a photograph taken by a photographer at a crime scene is maintained from the point of image capture to its end application at trial. The requirements for such a system are specified and the results of experiments are presented which demonstrate the feasibility of the proposed approach.

Neville, Timothy; Sorell, Matthew

269

Electromagnetic-induction logging to monitor changing chloride concentrations.  

PubMed

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. PMID:22607466

Metzger, Loren F; Izbicki, John A

2013-01-01

270

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

271

2010 Daily Fire Log Date & Time  

E-print Network

and transported to Campbell Co. jail. Fire/Smoke/Sprinkler Alarm Log December 2010 Report #: 2010-00571 Reported responded and cleared the scene; subject transported to Campbell County jail. #12;2010 Daily Fire Log CAD

Boyce, Richard L.

272

29 CFR 788.9 - “Preparing * * * logs.”  

Code of Federal Regulations, 2011 CFR

...AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS FORESTRY OR LOGGING OPERATIONS IN WHICH NOT MORE THAN EIGHT EMPLOYEES ARE EMPLOYED § 788.9 “Preparing * * * logs.”...

2011-07-01

273

29 CFR 788.9 - “Preparing * * * logs.”  

Code of Federal Regulations, 2010 CFR

...AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS FORESTRY OR LOGGING OPERATIONS IN WHICH NOT MORE THAN EIGHT EMPLOYEES ARE EMPLOYED § 788.9 “Preparing * * * logs.”...

2010-07-01

274

Technology & Science Web MSNBC Cosmic Log  

E-print Network

Home » Technology & Science » Science Web MSNBC Cosmic Log ABOUT COSMIC LOG Quantum fluctuations batteries. KN400, for example, could provide the energy for deep-sea sensors that monitor turtle migration

Lovley, Derek

275

29 CFR 1918.88 - Log operations.  

Code of Federal Regulations, 2010 CFR

...furnished and hung overside to the water's edge. (e) Jacob's ladder...employee is working logs out of the water, walking sticks 11 (safety sticks...loading of logs onto vessels from the water. (1) They shall be planked...

2010-07-01

276

29 CFR 1918.88 - Log operations.  

Code of Federal Regulations, 2012 CFR

...furnished and hung overside to the water's edge. (e) Jacob's ladder...employee is working logs out of the water, walking sticks 11 (safety sticks...loading of logs onto vessels from the water. (1) They shall be planked...

2012-07-01

277

29 CFR 1918.88 - Log operations.  

Code of Federal Regulations, 2011 CFR

...furnished and hung overside to the water's edge. (e) Jacob's ladder...employee is working logs out of the water, walking sticks 11 (safety sticks...loading of logs onto vessels from the water. (1) They shall be planked...

2011-07-01

278

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

279

29 CFR 788.9 - “Preparing * * * logs.”  

...AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS FORESTRY OR LOGGING OPERATIONS IN WHICH NOT MORE THAN EIGHT EMPLOYEES ARE EMPLOYED § 788.9 “Preparing * * * logs.”...

2014-07-01

280

29 CFR 788.9 - “Preparing * * * logs.”  

Code of Federal Regulations, 2013 CFR

...AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS FORESTRY OR LOGGING OPERATIONS IN WHICH NOT MORE THAN EIGHT EMPLOYEES ARE EMPLOYED § 788.9 “Preparing * * * logs.”...

2013-07-01

281

Precise inversion of logged slownesses for elastic parameters in a gas shale formation  

E-print Network

Dipole sonic log data recorded in a vertical pilot well and the associated production well are analyzed over a 200×1100-ft section of a North American gas shale formation. The combination of these two wells enables angular ...

Miller, Douglas E.

282

The Methodology of Search Log Analysis  

E-print Network

99 Chapter VI The Methodology of Search Log Analysis Bernard J. Jansen Pennsylvania State of and foundation for conducting Web search transaction log analysis. A search log analysis methodology is outlined consisting of three stages (i.e., collection, preparation, and analysis). The three stages of the methodology

Jansen, James

283

CORRUPTION AND ILLEGAL LOGGING IN THE WOOD  

E-print Network

deforestation Davide Pettenella University of Padova Agricultural University of Tirana Faculty of Forestry in deforestation and trade of illegal logging? 3. Which are the most affected countries? 4. Why do we need logging (World Bank Review of Global Forest Policy ­ 1999) Illegal logging have external effects

Pettenella, Davide

284

Balloon logging with the inverted skyline  

NASA Technical Reports Server (NTRS)

There is a gap in aerial logging techniques that has to be filled. The need for a simple, safe, sizeable system has to be developed before aerial logging will become effective and accepted in the logging industry. This paper presents such a system designed on simple principles with realistic cost and ecological benefits.

Mosher, C. F.

1975-01-01

285

What to expect when logging the Cotton Valley trend  

SciTech Connect

Exploration within the low-porosity, low-permeability sections of the Cotton Valley sands and limestones of E. Texas, Louisiana, and Arkansas has proven economic only within the last 5 to 8 yr due to improved gas prices and advanced reservoir analyzation and stimulation techniques. This work details those logging suites necessary to properly assess these less than optimum reservoirs, and illustrates, through specific well cases, how deliverability from well to well can vary due to delicate differences in reservoir properties. It is evident from the case wells illustrated that not all tight Cotton Valley sand or limestone wells result in high-rate flows. That being the case, it is important that detailed logging analysis be utilized so optimum stimulation procedures can be designed at each well site. Improperly place perforations or poorly designed and operated stimulation procedures can result in a bad well, where a successful one was possible.

Nangle, P.; Fertl, W.H.; Frost, E. Jr.

1982-10-01

286

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

287

Dewarless Logging Tool - 1st Generation  

SciTech Connect

This report focuses on Sandia National Laboratories' effort to create high-temperature logging tools for geothermal applications without the need for heat shielding. One of the mechanisms for failure in conventional downhole tools is temperature. They can only survive a limited number of hours in high temperature environments. For the first time since the evolution of integrated circuits, components are now commercially available that are qualified to 225 C with many continuing to work up to 300 C. These components are primarily based on Silicon-On-Insulator (SOI) technology. Sandia has developed and tested a simple data logger based on this technology that operates up to 300 C with a few limiting components operating to only 250 C without thermal protection. An actual well log to 240 C without shielding is discussed. The first prototype high-temperature tool measures pressure and temperature using a wire-line for power and communication. The tool is based around the HT83C51 microcontroller. A brief discussion of the background and status of the High Temperature Instrumentation program at Sandia, objectives, data logger development, and future project plans are given.

HENFLING,JOSEPH A.; NORMANN,RANDY A.

2000-08-01

288

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

289

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

290

Peoria`s log recycling program  

SciTech Connect

The City of Peoria had a problem: thousands of cubic yards of wood waste--tree limbs, logs, and trimmings stockpiled as a result of three years of operations and storms. They were faced with a potentially costly dilemma: how to dispose of this material without breaking the law or the budget? With intergovernmental cooperation and perseverance, they did it. The Peoria Park District had a problem, too. Between 1990 and 1992, three major storms downed and severely damaged many of the area`s trees. In addition, the city and Park District annually cut approximately 350 to 400 trees, as well as annual trimming in parks and along rights-of-way. The City had been hauling small and manageable material to the local compost site, but 5,500 cu yd of large-diameter trees and limbs remained stored on City property. The Park District had been pushing its material into a large ravine at one of the parks. But, in 1992, the Illinois Environmental Protection Agency ordered them to stop this practice. With the closure of its park disposal site, the Park District, like the city, began stockpiling. After reviewing various options, the city refocused on log recycling.

McKinley, D.W.

1994-11-01

291

Department of Recreational Sports Live Well. Learn Well. Be Well Recreational Sports  

E-print Network

Department of Recreational Sports Live Well. Learn Well. Be Well Recreational Sports oregonstate ___ Climbing Center Staff ___ Facility Operations Staff ___ Rec Services Staff ___ Facility/Equipment Maintenance Staff ___ Fitness Staff ___ Graphic Designer Staff ___ Intramural Sports & Sport Club Staff

Escher, Christine

292

Non--global logs and clustering impact on jet mass with a jet veto distribution  

Microsoft Academic Search

There has recently been much interest in analytical computations of jet mass distributions with and without vetos on additional jet activity [1-6]. An important issue affecting such calculations, particularly at next-to-leading log (NLL), is that of non-global logs (NGLs) as well as logs induced by jet definition, as pointed out in our previous work [3]. In this paper, we extend

Kamel Khelifa-Kerfa

2011-01-01

293

Log-periodic self-similarity: an emerging financial law?  

Microsoft Academic Search

A hypothesis that the financial log-periodicity, cascading self-similarly through various time scales, carries signatures of a law is pursued. It is shown that the most significant historical financial events can be classified amazingly well using a single and unique value of the preferred scaling factor ?=2, which indicates that its real value should be close to this number. This applies

S. Drozdz; F. Grümmer; F. Ruf; J. Speth

2003-01-01

294

A 1-V CMOS log-domain integrator  

Microsoft Academic Search

A novel circuit implementation of a CMOS log-domain integrator is presented. Unlike most other implementations, it does not require placing of MOSFETs in separated wells, and therefore allows very compact filters, which are fully compatible with modern standard CMOS technologies. Besides the saving of chip area, this also helps to reduce parasitic capacitances. The most important advantage of this circuit

Dominique Python; Manfred Punzenberger; Christian C. Enz

1999-01-01

295

Towards sharing life-log information with society  

Microsoft Academic Search

We are living in an era of social media such as online communities and social networking sites. Exposing or sharing personal information with these communities has risks as well as benefits and there is always a trade off between the risks versus the benefits of using these technologies. Life-logs are pervasive tools or systems which sense and capture contextual information

Reza Rawassizadeh

2012-01-01

296

Estimating the service time of web clients using server logs  

Microsoft Academic Search

This article proposes and evaluates measures for estimating the service time of a web client using server logs, only from the server side without introducing traffic into the network. The HTTP protocol is described as well as the different interactions between the web server, the communication components, and the web client application. The first measure is based on the time

Oscar Ardaiz; Felix Freitag; Leandro Navarro

2001-01-01

297

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

298

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

299

Analysis of Web Proxy Logs  

NASA Astrophysics Data System (ADS)

Network forensics involves capturing, recording and analysing network audit trails. A crucial part of network forensics is to gather evidence at the server level, proxy level and from other sources. A web proxy relays URL requests from clients to a server. Analysing web proxy logs can give unobtrusive insights to the browsing behavior of computer users and provide an overview of the Internet usage in an organisation. More importantly, in terms of network forensics, it can aid in detecting anomalous browsing behavior. This paper demonstrates the use of a self-organising map (SOM), a powerful data mining technique, in network forensics. In particular, it focuses on how a SOM can be used to analyse data gathered at the web proxy level.

Fei, Bennie; Eloff, Jan; Olivier, Martin; Venter, Hein

300

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

301

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

302

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

303

CORRELATOR 5.2—a program for interactive lithostratigraphic correlation of wireline logs  

NASA Astrophysics Data System (ADS)

The limited radius of investigation of petrophysical measurements made in boreholes and the relatively large distances between wells result in an incomplete sensing of the subsurface through well logging. CORRELATOR is a program for estimating geological properties between logged boreholes. An initial and fundamental step is the lithostratigraphic correlation of logs in different wells. The method employed by the program closely emulates the process of visual inspection used by experienced subsurface geologists in manual correlation. Mathematically, the determination of lithostratigraphical equivalence is based on the simultaneous assessment of similarity in shale content, similarity in the patterns of vertical variation in a petrophysical property that is measured with high vertical resolution, and spatial consistency of stratigraphic relationships as determined by an expert system. Multiple additional options for processing log readings allow maximization in the extraction of information from pairs of logs per well and great flexibility in the final display of results in the form of cross sections and dip diagrams.

Olea, Ricardo A.

2004-07-01

304

Log-Derived evaluation of shaly sandstone reservoirs  

SciTech Connect

Significant natural gas resources are known to exist in the United States in tight, low-permeability sandstones that cover a prospective area of 1,000,000 mi/sup 2/ (2,590,000 km/sup 2/). Characterization and reliable estimation of their production potential based on well logs are important although difficult task. Proper evaluation of low permeability sands based on conventional log-interpretation techniques is frequently inadequate. Furthermore, while empirical rules of thumb assist in the evaluation of localized conditions, they only provide guidelines. Recent developments in quantitative log-analysis techniques incorporate natural-gamma-ray spectral data and application of the Waxman-Smits model for detailed reservoir description. Quantitative correlations of cation exchange capacity (CEC), water salinity, porosity, and conductivity of water- and hydrocarbon-bearing shaly sand reservoirs are based on resistivity, density, neutron and natural-gamma-ray spectral data. These correlations provide important information about clay volume, reservoir porosities (total, effective) and fluid-saturation distribution (total, effective), type of clay minerals (smectite, illite, chlorite/kaolinite), their distribution in the reservoir (dispersed, laminated, structural), and log-derived indicators of potential formation damage. Field experiences are reviewed for logging and evaluating tight formations in south Texas; the Jurassic Cotton Valley trend in east Texas, Louisiana, and Arkansas; and the Tertiary Fort Union and Cretaceous Mesaverde Formations of the Piceance basin in Colorado.

Fertl, W.H.

1984-04-01

305

Approximate Effects of Off-Center Acoustic Sondes and Elliptic Boreholes Upon Full Waveform Logs  

E-print Network

Full waveform acoustic well logging has become instrumental to hydrocarbon exploration because of its ability to determine in situ velocity information for P and S waves as well as the attenuation (or absorption) of seismic ...

Willis, M. E.

1983-01-01

306

Selective logging and its relation to deforestation  

NASA Astrophysics Data System (ADS)

Selective logging is a major contributor to the social, economic, and ecological dynamics of Brazilian Amazonia. Logging activities have expanded from low-volume floodplain harvests in past centuries to high-volume operations today that take about 25 million m3 of wood from the forest each year. The most common highimpact conventional and often illegal logging practices result in major collateral forest damage, with cascading effects on ecosystem processes. Initial carbon losses and forest recovery rates following timber harvest are tightly linked to initial logging intensity, which drives changes in forest gap fraction, fragmentation, and the light environment. Other ecological processes affected by selective logging include nutrient cycling, hydrological function, and postharvest disturbance such as fire. This chapter synthesizes the ecological impacts of selective logging, in the context of the recent socioeconomic conditions throughout Brazilian Amazonia, as determined from field-based and remote sensing studies carried out during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia program.

Asner, Gregory P.; Keller, Michael; Lentini, Marco; Merry, Frank; Souza, Carlos, Jr.

307

Principles of well diagnosis  

SciTech Connect

Well performance analysis provides an effective engineering resource for the analysis of well problems and the benefit possible from well workovers or well stimulation to improve well performance. Transient pressure testing and analysis has long been used to identify formation potential and to disclose wellbore restrictions; however, this methodology does not identify the source of restricted flow or a realistic potential of a well completion change. Well diagnosis not only involves pressure transient testing and analysis, but also well completion procedure analysis, well log analysis, special petrographic analysis, and flowing well system analysis (often called Nodal Analysis). Although reservoir flow and tubular flow are important in this systems analysis, well completion modeling is often the key to improvements through workover or stimulation. Several completion or wellbore models have been developed and presented in the last 20 years. Those models dealing with perforated wells and gravel packed wells will be reviewed and illustrated with case histories that demonstrate how well systems analysis leads to improved well performance. The geology of the formation is often critical in the analysis of formation damage and interpretation of well production problems, especially when flow is not sufficient to allow pressure transient testing. Well completion operation analysis is a developing art which incorporates an understanding of the latest research and a familiarity with field practice, and a strategy for this analysis will be provided.

McLeod, H.O.

1994-12-31

308

Toxic species evolution from guayule fireplace logs  

E-print Network

or cellulose fiberboard. As expected, the amount of smoke produced by burning a guayule fireplace log under test conditions was far less than the smoke produced by burning a synthetic plastic material such as polyvinyl chloride. It should be noted... Smoke Test Data for Selected Materials ' MATERIALS PERCENT SMOKE+ BASED ON INITIAL MASS MASS LOSS Southern Yellow Pine Red Oah Medium Density Hardborad Guayuie Fireplace Log Cotton Gin Trash Fireplace Log Cellulose Fiberboard Polyvinyl...

Soderman, Kristi Lee

2012-06-07

309

Weekly Security Incident Log Period of May 14 -May 20, 2012  

E-print Network

Property Complainant reported the theft of computer equipment from a secure office area-000955 PARKING GARAGE - ARBORETUM LANE (PS2) Mech\\Electrical Security responded to a report that an automotiveWeekly Security Incident Log Period of May 14 - May 20, 2012 Incident No. Reported Date Building

310

Extended reach and horizontal wells experienced on the Statfjord field  

SciTech Connect

Statfjord field, the largest producing field in Europe, is located 200 km northwest of Bergen, Norway on the United Kingdom/Norwegian boundary. Statfjord field is being developed with three fully integrated platforms of concrete gravity based on Condeep design. The Statfjord field consists of four reservoirs: Upper Brent, Lower Brent, Dunlin, and Statfjord, which are developed separately. The overall objective for the horizontal and extended reach wells on Statfjord is to maximize the field recovery and accelerate production at a minimal cost. This is done by drilling extended reach wells to the far-away flanks of the field and drilling horizontal wells to drain fault blocks and erosion zones in the Brent reservoir and wedge zones in the Statfjord reservoir. To date, a total of 11 horizontal and extended reach wells have been drilled and completed on Statfjord field. The following have been key factors in drilling the horizontal and extended reach wells: well profile, torque and drag, equipment limitations, hole cleaning, hole stability, mud and cement programs, and surveying. To optimize the well profiles, extensive work has been put into simulating torque, drag, and ECDs. The well profiles are optimized with regards to drilling, completion, and workover, in addition to the reservoir targets. The completion is designed to be able to perform all future work through tubing. Factors like zone isolation requirements, well profile, casing program, logging/testing/perforating requirements, and sand production are considered when planning the completion. A 7 in. monobore completion string together with a 7 in. cemented liner is used to meet the completion objective. Several production logging tool, bridge plug, and perforation jobs have been performed on coiled tubing in horizontal wells on Statfjord field. Problems related to hole cleaning, well killing, fishing, and packer setting have been experienced during drilling and completion of the wells.

Kostol, P.; Tjotta, H. (Statoil, Stavanger (Norway))

1993-09-01

311

Computing Reliability Distributions of Windowed Max-log-map (MLM) Detectors : ISI Channels  

E-print Network

Computing Reliability Distributions of Windowed Max-log-map (MLM) Detectors : ISI Channels Fabian-log-map (MLM) detector has well-known appli- cations to the intersymbol interefence (ISI) channel [1, · · · , is trans- mitted across the ISI channel. Let the following random This work was performed when F. Lim

Kavcic, Aleksandar

312

A hybrid constraint programming approach to the log-truck scheduling problem  

Microsoft Academic Search

Scheduling problems in the forest industry have received sig- nificant attention in the recent years and have contributed many chal- lenging applications for optimization technologies. This paper proposes a solution method based on constraint programming and mathematical programming for a log-truck scheduling problem. The problem consists of scheduling the transportation of logs between forest areas and woodmills, as well as

Michel Gendreau; Louis-Martin Rousseau

2011-01-01

313

Reservoir characterization of the Melbourn and F-39 sands in the Lavaca Bay field using integration of log, core and production data  

E-print Network

PARAMETERS OF RECOMPLETION TARGETS IN UNIT I . . . 41 5. LOG PARAMETERS OF RECOMPLETION TARGETS IN UNIT II . . . 41 6. LOG PARAMETERS OF PRODUCER WELLS (F-39) . . . . . 42 7. LOG PARAMETERS OF RECOMPLETION TARGETS (F-39) . . . . . 45 8. Bg... interpretation of Well Alcoa?9 6. Log interpretation of Well St Tr-26?5 7. Top of the Melbourn sand 8. Formation water resistivity (Rw) distribution . . 28 31 . . . . . . . 36 9. Resistivity of the Melbourn sand - Unit I . . . . . 37 10. Sw...

Hong, Cecelia

2012-06-07

314

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

315

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. PMID:24628366

Linkie, Matthew; Sloan, Sean; Kasia, Rahmad; Kiswayadi, Dedy; Azmi, Wahdi

2014-08-01

316

Microstrip log periodic antenna using circuit simulator  

Microsoft Academic Search

This paper described the method of designing the quasi log periodically scaled microstrip antenna using S parameter of the antenna and microstrip transmission line circuit. The novelty of this antenna structure is a combination of a small number of elements to create a log periodic array with modest bandwidth. The radiating element is a square patch antenna. The input impedance

M. K. A. Rahim; P. Gardner

2003-01-01

317

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

318

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. PMID:24761134

BALABDAOUI, FADOUA; WELLNER, JON A.

2014-01-01

319

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. PMID:24330636

2013-01-01

320

Security Event and Log Management Service  

E-print Network

Services - The Smarter Decision 6 Introducing IBM Internet Security Systems Security Event and Log (SOC) Event Monitoring Service 13 Conclusion 14 Protection on demand 14 Contact IBM Internet Security Systems to Learn More 14 About IBM Internet Security Systems Contents Security Event and Log Management

321

Using Satellite Imagery to Detect Illegal Logging  

E-print Network

.globalforestwatch.org/english/about/illeglog/illeglog_workshop_presentations.htm #12;GFW Remote Sensing Work on Illegal Logging · Cameroon ­ pilot dataset completed · Central Africa · Applications outside Central Africa · Make Landsat Imagery freely available · Provide new datasets (logging

322

Shippers in Indonesia fight decree on illegal logging Shippers in Indonesia fight decree on illegal logging  

E-print Network

Shippers in Indonesia fight decree on illegal logging Shippers in Indonesia fight decree on illegal Organization (ITTO), shippers in Indonesia are threatening to stop transporting logs if the government insists harvesting affects 700,000-850,000 hectares of forest per year in Indonesia, but widespread illegal logging

323

Energy Audit Equipment  

E-print Network

The tools (equipment) needed to perform an energy audit include those items which assist the auditor in measuring the energy used by equipment or lost in inefficiency. Each tool is designed for a specific measurement. They can be inexpensive simple...

Phillips, J.

2012-01-01

324

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

325

Log step and clast interactions in mountain streams in the central Cascade Range of Washington State, USA  

NASA Astrophysics Data System (ADS)

Field surveys of log steps in high-gradient streams investigate the interactions between log steps and clasts to assess whether second-growth wood can form log steps capable of diverting flow and acting as significant roughness elements similar to those formed by old-growth wood. We measure the functional log diameter and step height, as well as visually estimate the clast size in the step of 102 log steps in 15 high-gradient streams in the central Cascade Range of Washington, USA. We compare step height data to measurements of maximum bankfull depth to measure the capability of log steps to divert flow relative to their clast size and log diameter. Step height positively correlates with functional log diameter (p < 0.001) and clast size. Additionally, a threshold clast size exists above which functional log diameter more strongly correlates with step height, indicating that clast size can limit step height. We find that steps with cobble or larger (> 64 mm) clasts in the step are 3.7 times more likely to reach or exceed bankfull depth than steps with smaller than cobble clasts in the step. We conclude that it is necessary for steps formed by small logs to have large clasts in the step in order to reach bankfull depth, act as significant roughness elements, and create flow diversions, implying that the potential for second-growth forests to maintain log steps similar to those formed by old-growth logs depends on the size of bed material.

Scott, Daniel N.; Montgomery, David R.; Wohl, Ellen E.

2014-07-01

326

Annual Logging Symposium, June 22-26, 2013 MISCIBILITY EFFECTS OF OIL-BASE MUD AND IN-SITU GAS ON  

E-print Network

, The University of Texas at Austin Copyright 2013, held jointly by the Society of Petrophysicists and Well Log-density logs. Phase behavior of hydrocarbon fluids indicates that any multi-component system, under given

Torres-Verdín, Carlos

327

Log-amplitude statistics for Beck-Cohen superstatistics.  

PubMed

As a possible generalization of Beck-Cohen superstatistical processes, we study non-Gaussian processes with temporal heterogeneity of local variance. To characterize the variance heterogeneity, we define log-amplitude cumulants and log-amplitude autocovariance and derive closed-form expressions of the log-amplitude cumulants for ?(2), inverse ?(2), and log-normal superstatistical distributions. Furthermore, we show that ?(2) and inverse ?(2) superstatistics with degree 2 are closely related to an extreme value distribution, called the Gumbel distribution. In these cases, the corresponding superstatistical distributions result in the q-Gaussian distribution with q=5/3 and the bilateral exponential distribution, respectively. Thus, our finding provides a hypothesis that the asymptotic appearance of these two special distributions may be explained by a link with the asymptotic limit distributions involving extreme values. In addition, as an application of our approach, we demonstrated that non-Gaussian fluctuations observed in a stock index futures market can be well approximated by the ?(2) superstatistical distribution with degree 2. PMID:23767484

Kiyono, Ken; Konno, Hidetoshi

2013-05-01

328

A small-diameter NMR logging tool for groundwater investigations.  

PubMed

A small-diameter nuclear magnetic resonance (NMR) logging tool has been developed and field tested at various sites in the United States and Australia. A novel design approach has produced relatively inexpensive, small-diameter probes that can be run in open or PVC-cased boreholes as small as 2 inches in diameter. The complete system, including surface electronics and various downhole probes, has been successfully tested in small-diameter monitoring wells in a range of hydrogeological settings. A variant of the probe that can be deployed by a direct-push machine has also been developed and tested in the field. The new NMR logging tool provides reliable, direct, and high-resolution information that is of importance for groundwater studies. Specifically, the technology provides direct measurement of total water content (total porosity in the saturated zone or moisture content in the unsaturated zone), and estimates of relative pore-size distribution (bound vs. mobile water content) and hydraulic conductivity. The NMR measurements show good agreement with ancillary data from lithologic logs, geophysical logs, and hydrogeologic measurements, and provide valuable information for groundwater investigations. PMID:23425428

Walsh, David; Turner, Peter; Grunewald, Elliot; Zhang, Hong; Butler, James J; Reboulet, Ed; Knobbe, Steve; Christy, Tom; Lane, John W; Johnson, Carole D; Munday, Tim; Fitzpatrick, Andrew

2013-01-01

329

Renewal of radiological equipment.  

PubMed

In this century, medical imaging is at the heart of medical practice. Besides providing fast and accurate diagnosis, advances in radiology equipment offer new and previously non-existing options for treatment guidance with quite low morbidity, resulting in the improvement of health outcomes and quality of life for the patients. Although rapid technological development created new medical imaging modalities and methods, the same progress speed resulted in accelerated technical and functional obsolescence of the same medical imaging equipment, consequently creating a need for renewal. Older equipment has a high risk of failures and breakdowns, which might cause delays in diagnosis and treatment of the patient, and safety problems both for the patient and the medical staff. The European Society of Radiology is promoting the use of up-to-date equipment, especially in the context of the EuroSafe Imaging Campaign, as the use of up-to-date equipment will improve quality and safety in medical imaging. Every healthcare institution or authority should have a plan for medical imaging equipment upgrade or renewal. This plan should look forward a minimum of 5 years, with annual updates. Teaching points • Radiological equipment has a definite life cycle span, resulting in unavoidable breakdown and decrease or loss of image quality which renders equipment useless after a certain time period.• Equipment older than 10 years is no longer state-of-the art equipment and replacement is essential. Operating costs of older equipment will be high when compared with new equipment, and sometimes maintenance will be impossible if no spare parts are available.• Older equipment has a high risk of failure and breakdown, causing delays in diagnosis and treatment of the patient and safety problems both for the patient and the medical staff.• Every healthcare institution or authority should have a plan for medical imaging equipment upgrade or replacement. This plan should look forward a minimum of 5 years, with annual updating. PMID:25230589

2014-10-01

330

30 CFR 250.602 - Equipment movement.  

Code of Federal Regulations, 2013 CFR

...well-workover 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

331

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

332

30 CFR 250.502 - Equipment movement.  

Code of Federal Regulations, 2011 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...

2011-07-01

333

30 CFR 250.502 - Equipment movement.  

Code of Federal Regulations, 2012 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...

2012-07-01

334

30 CFR 250.602 - Equipment movement.  

Code of Federal Regulations, 2010 CFR

...well-workover 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...

2010-07-01

335

30 CFR 250.502 - Equipment movement.  

Code of Federal Regulations, 2010 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...

2010-07-01

336

30 CFR 250.602 - Equipment movement.  

Code of Federal Regulations, 2012 CFR

...well-workover 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...

2012-07-01

337

30 CFR 250.602 - Equipment movement.  

Code of Federal Regulations, 2011 CFR

...well-workover 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...

2011-07-01

338

Adaptive Fluid Electrical Conductivity Logging to Determine the Salinity Profiles in Groundwater  

E-print Network

logging techniques To measure inflows into the well as a function of depth and to identify hydraulic of water flow. Area under peak is proportional to qiCi ( qi is inflow rate at a particular feed point

Quinn, Nigel

339

Annual Logging Symposium, June 22-26, 2013 ESTIMATION OF NEAR-WELLBORE RELATIVE PERMEABILITY  

E-print Network

at Austin Copyright 2013, held jointly by the Society of Petrophysicists and Well Log Analysts (SPWLA and paucity, their reliability to predict real-time production behavior of heterogeneous formations remains

Torres-Verdín, Carlos

340

Annual Logging Symposium, June 26-29, 2005 INFLUENCE OF OIL SATURATION AND WETTABILITY  

E-print Network

-Verdín, The University of Texas at Austin Copyright 2005, held jointly by the Society of Petrophysicists and Well Log, non-Archie behavior, frequently takes place in rocks exhibiting oil wettability or irregular pore

Torres-Verdín, Carlos

341

Annual Logging Symposium, June 16-20, 2012 SATURATION-HEIGHT AND INVASION CONSISTENT HYDRAULIC  

E-print Network

of Texas at Austin Copyright 2012, held jointly by the Society of Petrophysicists and Well Log Analysts. Reliable hydraulic rock typing should simultaneously honor saturation behavior in the vertical direction

Torres-Verdín, Carlos

342

Annual Logging Symposium, June 3-6, 2007 INFLUENCE OF PETROPHYSICAL AND FLUID PROPERTIES ON  

E-print Network

, The University of Texas at Austin Copyright 2007, held jointly by the Society of Petrophysicists and Well Log that oil viscosity and oil density are both dependent on component concentrations. This behavior in turn

Torres-Verdín, Carlos

343

A receiving array of log-periodic dipoles  

NASA Astrophysics Data System (ADS)

The mutual impedance of dipoles for a modified vertical log-periodic dipole antenna is analyzed with allowance for mutual coupling effects. Formulas are presented for calculating the radiation pattern and impedance for an antenna array above the ground system. It is shown that the arrays performed relatively well over a 4.3:1 bandwidth while being phase-scanned over an azimuth range of + or - 45 deg.

Yang, Rongxi; Huang, Chibiao; Xia, Lianrong

344

Evaluation of log-transformation in assessing bioequivalence  

Microsoft Academic Search

The question of whether we should use log-transformed data in assessing bioequivalence between two formulations is studied through a simulation. Under a 2×2 cross-over design with different combinations of sample size and intrasubject variability, we examine the impacts of different scales of the data on the conclusion of bioequivalence as well as on the level of significance and power. We

Jen-Pei Liu; Chung-Sing Weng

1994-01-01

345

2010 Daily Log Report #: 2010-00262  

E-print Network

of Marijuana Report #: 2010-00256 Reported: 06/17/10 0851 Occurred: Same Incident: Traffic Crash Location: Lot;2010 Daily Log Report #: 2010-00249 Reported: 06/03/10 1702 Occurred: Same Incident: Medical Emergency

Boyce, Richard L.

346

Daily Crime Log Wednesday, June 25, 2014  

E-print Network

Daily Crime Log Wednesday, June 25, 2014 8:53:25 AM Calendar Year: 2014 Date/Time Reported Offense) CO A 17-year-old juvenile was issued a Carbondale City notice to appear and released. (140619001) LOT

347

Dewarless Logging Tool - 1st Generation.  

National Technical Information Service (NTIS)

This report focuses on Sandia National Laboratories' effort to create high-temperature logging tools for geothermal applications without the need for heat shielding. One of the mechanisms for failure in conventional downhole tools is temperature. They can...

Henfling Normann

2000-01-01

348

Business Plan SYMAS Custom Log Fencing LTD.  

E-print Network

..........................................................,....32 #12;1 Executive Summary SYMAS is a fencing products company, specializing in custom rustic log with express written consent. #12;Table of Contents Executive Summary.......................................................................19 5.0 Operations...............................................................21 5.1 Scope

349

Formation mechanical properties and the sonic log  

SciTech Connect

A program is presented that calculates the mechanical properties of reservoir rocks from sonic logs. The program was written in Microsoft BASIC and the source code for MS-DOS, Apple Macintosh, and Amiga personal computers is given.

Elphick, R.Y.

1988-11-01

350

Logging-while-coring method and apparatus  

DOEpatents

A method and apparatus for downhole coring while receiving logging-while-drilling tool data. The apparatus includes core collar and a retrievable core barrel. The retrievable core barrel receives core from a borehole which is sent to the surface for analysis via wireline and latching tool The core collar includes logging-while-drilling tools for the simultaneous measurement of formation properties during the core excavation process. Examples of logging-while-drilling tools include nuclear sensors, resistivity sensors, gamma ray sensors, and bit resistivity sensors. The disclosed method allows for precise core-log depth calibration and core orientation within a single borehole, and without at pipe trip, providing both time saving and unique scientific advantages.

Goldberg, David S. (New York, NY); Myers, Gregory J. (Cornwall, NY)

2007-11-13

351

47 CFR 80.409 - Station logs.  

Code of Federal Regulations, 2011 CFR

...ensure the continued proper functioning of GMDSS equipment shall be made. (4) An entry describing any malfunctioning GMDSS equipment and another entry when the...Officer of the Navigational Watch, or GMDSS Operator on watch, if one is...

2011-10-01

352

47 CFR 80.409 - Station logs.  

Code of Federal Regulations, 2012 CFR

...ensure the continued proper functioning of GMDSS equipment shall be made. (4) An entry describing any malfunctioning GMDSS equipment and another entry when the...Officer of the Navigational Watch, or GMDSS Operator on watch, if one is...

2012-10-01

353

Annual Logging Symposium, June 22-26, 2013 Copyright 2013, held jointly by the Society of Petrophysicists and Well Log  

E-print Network

this problem, we introduce a new Bayesian approach that inherently adopts the scientific method of iterative with maximum likelihood, the Bayesian method quantifies the uncertainty of rock types and associated technique based on the Markov-Chain Monte Carlo method, thereby enabling an efficient search of rock types

Torres-Verdín, Carlos

354

DOE/Simplec magnetic susceptibility logging system  

SciTech Connect

A magnetic susceptibility logging system has been developed which is relatively stable under normal field logging conditions and which produces logs that accurately represent in situ variations in magnetic susceptibility. However, both field and laboratory tests indicate the need for further improvement of temperature stabilization and bridge compensation; a new generation system designed by Simplec may fill that need. A cubic granite block with a magnetic susceptibility of 385 ..mu..CGS is designated as the primary calibration standard and is available for public use at the DOE facility in Grand Junction, Colorado. Models are also available for characterization of magnetic susceptibility systems. These include models to provide borehole size correction factors, thin layer interpretation parameters, reproducibility limits, longitudinal resolution, and radius of investigation. The DOE/Simplec system has a 99-percent radius of investigation, approximately equal to the coil length (15 inches), and a 99-percent thickness of investigation, approximately equal to two coil lengths. The true magnetic susceptibility and thickness of isolated layers less than two coil lengths in thickness can be obtained through use of parameters measured from their log responses. Field tests show that the system has a reproducibility of at least 5 ..mu..CGS and that logging at 25 ft/min is a good compromise between speed of operation and keeping the probe on the sidewall. Comparison of log and core magnetic susceptibility measurements confirms the fact that the logging system samples a rather large volume and that interpretive aids are necessary to unfold the true variation of magnetic susceptibility with depth. Finally, logs from known uranium-favorable environments show that magnetic susceptibility measurements can give an indication of the degree of geochemical alteration, which is one of the uranium-favorable haloes sought by exploration geologists.

Emilia, D.A.; Allen, J.W.; Chessmore, R.B.; Wilson, R.B.

1981-03-01

355

Conversation Threads Hidden within Email Server Logs  

NASA Astrophysics Data System (ADS)

Email server logs contain records of all email Exchange through this server. Often we would like to analyze those emails not separately but in conversation thread, especially when we need to analyze social network extracted from those email logs. Unfortunately each mail is in different record and those record are not tided to each other in any obvious way. In this paper method for discussion threads extraction was proposed together with experiments on two different data sets - Enron and WrUT..

Palus, Sebastian; Kazienko, Przemys?aw

356

Log-periodic route to fractal functions  

Microsoft Academic Search

Log-periodic oscillations have been found to decorate the usual power-law behavior found to describe the approach to a critical point, when the continuous scale-invariance symmetry is partially broken into a discrete-scale invariance symmetry. For Ising or Potts spins with ferromagnetic interactions on hierarchical systems, the relative magnitude of the log-periodic corrections are usually very small, of order 10-5. In growth

S. Gluzman; D. Sornette

2002-01-01

357

Log interpretation of shaly sandstones  

E-print Network

Simandoux); and plot (f) is de Witte (1950) . . . 70 27 Comparison of the three shaly ? sandstone equations that yield the least reliable results in sand 4 of the Reese Intracoastal Land ()2 well. Plot (d) is Alger et al (1963); plot (e) is Poupon et... 630-1 well. Plot (d) is Alger et al (1963); plot (e) is Poupon et al (1970) (modified Simandoux); and plot (f) is de Witte (1950) . 75 32 (a) Generalized diagrammatic view of a system containing both laminated and dispersed clays. (b) Schematic...

Baker, Joel Foster

2012-06-07

358

47 CFR 73.782 - Retention of logs.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 false Retention of logs. 73.782 Section 73.782 Telecommunication FEDERAL COMMUNICATIONS COMMISSION...SERVICES International Broadcast Stations § 73.782 Retention of logs. Logs of international...

2010-10-01

359

Deep Space Network equipment performance, reliability, and operations management information system  

NASA Technical Reports Server (NTRS)

The Deep Space Mission System (DSMS) Operations Program Office and the DeepSpace Network (DSN) facilities utilize the Discrepancy Reporting Management System (DRMS) to collect, process, communicate and manage data discrepancies, equipment resets, physical equipment status, and to maintain an internal Station Log. A collaborative effort development between JPL and the Canberra Deep Space Communication Complex delivered a system to support DSN Operations.

Cooper, T.; Lin, J.; Chatillon, M.

2002-01-01

360

RETRIEVAL EQUIPMENT DESCRIPTIONS  

SciTech Connect

The objective and the scope of this document are to list and briefly describe the major mobile equipment necessary for waste package (WP) retrieval from the proposed subsurface nuclear waste repository at Yucca Mountain. Primary performance characteristics and some specialized design features of the equipment are explained and summarized in the individual subsections of this document. There are no quality assurance requirements or QA controls in this document. Retrieval under normal conditions is accomplished with the same fleet of equipment as is used for emplacement. Descriptions of equipment used for retrieval under normal conditions is found in Emplacement Equipment Descriptions, DI: BCAF00000-01717-5705-00002 (a document in progress). Equipment used for retrieval under abnormal conditions is addressed in this document and consists of the following: (1) Inclined Plane Hauler; (2) Bottom Lift Transporter; (3) Load Haul Dump (LHD) Loader; (4) Heavy Duty Forklift for Emplacement Drifts; (5) Covered Shuttle Car; (6) Multipurpose Vehicle; and (7) Scaler.

J. Steinhoff

1997-08-25

361

First Riser Logging in Scientific Ocean Drilling: Operational Planning and results/reality  

NASA Astrophysics Data System (ADS)

The first wireline logging, downhole stress measurement, and two-ship walkaway VSP (Vertical Seismic Profiling) were conducted in the riser drilled hole during IODP Expedition 319 in 2009. The hole C0009 is first riser drilling hole in ODP/IODP history by JAMSTEC D/V Chikyu. The expedition 319 is one of series of NanTroSEIZE Project, which goal is to reveal earthquake mechanism in Nankai trough seismogenic zone in Japan. The hole C0009 is drilled at TD 1603.7mbsf under 2054m sea water. Sampling cores, cutting analysis, gas monitoring, wireline logging, downhole stress measurement, and two-ship walkaway VSP (Vertical Seismic Profiling) were conducted. This presentation report the operational planning, results and reality. IODP standard wireline logging items: natural gamma-ray, resistivity, density, porosity, sonic velocity, resistivity image were measured. The advantages of riser dilled hole against riserless drilled hole for wireline logging are 1) stable hole condition, 2) accurate environmental correction by controlled drilling mud, and 3) large variation of tool selection because of regular hole size instead of slimhole by conventional IODP riser drilling. A couple of new tools were used for new measurement and improvement of the data quality. The SonicScanner (trademark of Schulumberger) successfully measured compressional and share velocity in very low velocities at the soft sediment, where it has been difficult to measure them with conventional DSI tool. The stress and pore pressure in the borehole were measured with the wireline logging tool, (Schlumberger MDT). The single probe tool enable to measure temporal formation fluid pressure. The double packer tool enable to fracture test by sealing and pumping in the borehole. These in-situ measurement and stress experiment data are very important to understand physical properties and mechanism of fault zone. Super long offset walkaway VSP was conducted to reveal detail subsurface structure and velocity distribution. The 16 sets of the no planned 3-C geophone are clumped with 15m spacing at ~1300-1600mbsf in the cased C0009 hole by Chikyu. Eight OBS (Ocean Bottom Seismometer)s deployed at the seafloor. JAMSTEC R/V Kairei shot along 53km line (maximum offset from the hole is ~30km) and round 3.5km circle with 16-array tuned air-gun. Zero-offset VSP was conducted to measure velocity and create seismogram along the well as well. Using high resolution data obtained from the equipment, detailed structural interpretation, anisotropy analysis, and shear velocity analysis are being carried out. Riser drilling takes not only operational advantages such as deeper and safety hole, but also scientific advantage such as increasing measurement items which has never done in riserless drilling and improving data quality. It enlarge the options to approach new discovery and Science.

Sanada, Yoshinori; Kyaw Thu, Moe; Kido, Yukari; Kawamura, Yoshihisa; Hino, Ryota; Eguchi, Nabuhisa; Toczko, Sean; Takahashi, Kyoma; 319 Science Party, Iodp

2010-05-01

362

Field Demonstration of Slim-hole Borehole Nuclear Magnetic Resonance (NMR) Logging Tool for Groundwater Investigations  

NASA Astrophysics Data System (ADS)

Nuclear magnetic resonance (NMR) methods provide estimates of free and bound water content and hydraulic conductivity, which are critically important for groundwater investigations. Borehole NMR tools have been available and widely used in the oil industry for decades, but only recently have been designed for small diameter boreholes typical of groundwater investigations. Field tests of an 89-mm-diameter borehole NMR logging tool are presented. This borehole NMR logging tool was developed for economical NMR logging of 100- to 200-mm-diameter boreholes, and specifically for characterizing hydraulic properties in the top 200 m of the subsurface. The tool has a vertical resolution of 0.5 m, a minimum echo spacing of 2.0 ms, and a radial depth of investigation of 178 to 203 mm, which typically is beyond the annulus of observation wells. It takes about 15 minutes to collect a data sample for each 0.5-m interval. The borehole NMR logging tool was field tested during spring 2010, in PVC-cased wells at sites in East Haddam and Storrs, Connecticut; Cape Cod, Massachusetts; Lexington, Nebraska; Lawrence, Kansas; and Rifle, Colorado. NMR logging yielded estimates of bound water, free water, and total-water content, as well as continuous distributions of water content versus transverse relaxation time (T2) at all depth levels. The derived water-content data were compared to the available ground-truth hydrogeologic data from each well, including drilling logs, neutron and other geophysical logs, and direct measurements of hydraulic conductivity. The results indicate that the borehole NMR logging tool provides information on porosity, pore-size distribution, and estimated hydraulic conductivity that cannot be duplicated by any other single geophysical logging tool.

Walsh, D.; Turner, P.; Frid, I.; Shelby, R.; Grunewald, E. D.; Magnuson, E.; Butler, J. J.; Johnson, C. D.; Cannia, J. C.; Woodward, D. A.; Williams, K. H.; Lane, J. W.

2010-12-01

363

Rock Mechanical Properties from Logs Petrophysics : Concepts and Results  

NASA Astrophysics Data System (ADS)

The objective of the "geomechanics from logs" (GML) research project is to develop model-driven predictive software for determining rock mechanical properties (specifically rock strength, compressibility and fracability) from other, more easily measured, rock properties (e.g. lithology, porosity, clay volume, velocity) routinely derived from nuclear, resistivity and acoustic logging tools. To this end, geomechanics from logs seeks to increase fundamental understanding of the primary geologic controls on rock mechanical properties and to translate this new insight into novel predictive tools. In detail, GML predictors rely on (i) the generation of relational rock mechanical properties databases incorporating QC'd core-based laboratory measurements (both in-house and high-precision published data); (ii) the use of established rock physics models (e.g. friable sand, contact cement models) to investigate theoretical relationships between geologic processes, reservoir environment, rock microstructure and elastic, bulk and transport petrophysical attributes/properties; (iii) the subdivision of database rocks into generic lithotypes (e.g. sand, shaly sand, sandy shale, shale) with common petrophysical attributes/properties; (iv) the use of multivariate statistics to generate lithotype-dependent empirical predictive relationships between mechanical properties and log-derived petrophysical attributes/properties; (v) the estimation of uncertainties associated with predictive function parameters; (vi) the application and validation of mechanical properties predictive tools to well-documented case studies (e.g. sand strength for perforation stability, rock compressibility for reservoir simulation) to test overall performance and quantify uncertainty in predictions. This paper presents the results of various rock strength, rock compressibility and rock fracability case studies conducted in wells of different stratigraphic age and depositional environment. Overall, GML (i) facilitated a step-change in fundamental (rock physics-based) understanding of complex geologic controls (rock microstructure and reservoir environment) on formation mechanical parameters; (ii) generated predictive algorithms relating core-derived rock mechanical parameters (specifically formation strength, compressibility and fracability) to petrophysical parameters determined directly from logging tools; and (iii) resulted in the implementation of these predictive algorithms and associated uncertainty quantification within log-analysis software.

Gaillot, Philippe; Crawford, Brian; Alramahi, Bashar; Karner, Steve

2010-05-01

364

Unveiling ALMA software behavior using a decoupled log analysis framework  

NASA Astrophysics Data System (ADS)

ALMA Software is a complex distributed system installed in more than one hundred of computers, which interacts with more than one thousand of hardware device components. A normal observation follows a flow that interacts with almost that entire infrastructure in a coordinated way. The Software Operation Support team (SOFTOPS) comprises specialized engineers, which analyze the generated software log messages in daily basis to detect bugs, failures and predict eventual failures. These log message can reach up to 30 GB per day. We describe a decoupled and non-intrusive log analysis framework and implemented tools to identify well known problems, measure times taken by specific tasks and detect abnormal behaviors in the system in order to alert the engineers to take corrective actions. The main advantage of this approach among others is that the analysis itself does not interfere with the performance of the production system, allowing to run multiple analyzers in parallel. In this paper we'll describe the selected framework and show the result of some of the implemented tools.

Gil, Juan Pablo; Tejeda, Alexis; Shen, Tzu-Chiang; Saez, Norman

2014-07-01

365

Calibration of density logs at the Nevada Test Site  

SciTech Connect

During the evaluation of a proposed site for an underground nuclear test at the Department of Energy`s Nevada Test Site (NTS) it was important to measure the bulk density of the geological formation in which the test was to be executed. The most satisfactory method for this measurement is the density log. This is a measurement system in which a gamma-ray source and detector are mounted in an instrument (a sonde) which is lowered into a borehole by a multi-conductor cable, and the number of gamma rays detected is used to infer the bulk density. At NTS many of the boreholes of interest are air-filled, with diameters as large as 3.65 m, drilled in partially-saturated media. Consequently the commercial equipment and calibration procedures are not suitable for NTS conditions. The count rate from a density sonde is strongly affected by any gap between the sonde and the borehole wall, especially if the gap is filled with air rather than water. Modern commercial density logs employ two detectors, and use one of the detectors to compensate for borehole conditions such as mudcake and gap. The commercial compensation algorithms assume that the sonde is parallel to the borehole wall; a reasonable assumption for oilfield conditions but not for NTS conditions. Moreover, in an air-filled borehole, borehole diameter affects both the calibration and the compensation. Therefore we could not use commercial algorithms to deal with NTS conditions. For many years, no appropriate two-detector algorithm was available for the NTS situation. Consequently we developed special algorithms for a single-detector sonde, which was equipped to measure the gap directly. Recently a two-detector algorithm was developed, which appears to be satisfactory if the sonde is calibrated in the appropriate-diameter borehole. In this report we describe the calibration procedures and the algorithms for both methods.

Hearst, J.R.

1995-04-01

366

Engineer Equipment Mechanic.  

ERIC Educational Resources Information Center

Developed as part of the Marine Corps Institute (MCI) correspondence training program, this course on engineer equipment mechanics is designed to advance the professional competence of privates through sergeants as equipment mechanics, Military Occupation Specialty 1341, and is adaptable for nonmilitary instruction. Introductory materials include…

Marine Corps Inst., Washington, DC.

367

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

368

Coal log pipeline research at the University of Missouri. 4th Quarterly report, October 1, 1993--December 31, 1993  

SciTech Connect

This paper is a progress report on a research project aimed at the development of coal log technology. Efforts have been directed at the development of technology for the fabrication of stable coal logs, as well as the energy efficient transport of these logs, in particular by pipelines. Work has been directed at new types of binders, new fabrication presses, the application of polymers to reduce transport losses, and modeling efforts.

Liu, H.

1994-05-01

369

Arabidopsis lonely guy (LOG) multiple mutants reveal a central role of the LOG-dependent pathway in cytokinin activation.  

PubMed

Cytokinins are phytohormones that play key roles in the maintenance of stem cell activity in plants. Although alternative single-step and two-step activation pathways for cytokinin have been proposed, the significance of the single-step pathway which is catalyzed by LONELY GUY (LOG), is not fully understood. We analyzed the metabolic flow of cytokinin activation in Arabidopsis log multiple mutants using stable isotope-labeled tracers and characterized the mutants' morphological and developmental phenotypes. In tracer experiments, cytokinin activation was inhibited most pronouncedly by log7, while the other log mutations had cumulative effects. Although sextuple or lower-order mutants did not show drastic phenotypes in vegetative growth, the log1log2log3log4log5log7log8 septuple T-DNA insertion mutant in which the LOG-dependent pathway is impaired, displayed severe retardation of shoot and root growth with defects in the maintenance of the apical meristems. Detailed observation of the mutants showed that LOG7 was required for the maintenance of shoot apical meristem size. LOG7 was also suggested to play a role for normal primary root growth together with LOG3 and LOG4. These results suggest a dominant role of the single-step activation pathway mediated by LOGs for cytokinin production, and overlapping but differentiated functions of the members of the LOG gene family in growth and development. PMID:22059596

Tokunaga, Hiroki; Kojima, Mikiko; Kuroha, Takeshi; Ishida, Takashi; Sugimoto, Keiko; Kiba, Takatoshi; Sakakibara, Hitoshi

2012-01-01

370

Determination of organic-matter content of Appalachian Devonian shales from gamma-ray logs.  

USGS Publications Warehouse

The organic-matter content of the Devonian shale of the Appalachian basin is important for assessing natural-gas resources. In most of the western part of the Appalachian basin the organic-matter content of the Devonian shale can be estimated from gamma-ray wire-line logs. Organic-matter contents estimated using these logs are compared with determinations from direct laboratory analyses of organic carbon for 74 intervals of varying thickness from 12 widely separated wells. The cumulative pool of gamma-ray logs for the Devonian shale forms a large and geographically broad data base. The approach may also be applicable to other formations.-from Author

Schmoker, J. W.

1981-01-01

371

Interpreting Horizontal Well Flow Profiles and Optimizing Well Performance by Downhole Temperature and Pressure Data  

E-print Network

Horizontal well temperature and pressure distributions can be measured by production logging or downhole permanent sensors, such as fiber optic distributed temperature sensors (DTS). Correct interpretation of temperature and pressure data can...

Li, Zhuoyi

2011-02-22

372

40 CFR 147.2104 - Requirements for all wells.  

...A pipe analysis log; or (2) A caliper log. (b) The owner or operator of a new injection well cased with plastic (PVC, ABS, or others) casings shall: (1) Not construct a well deeper than 500 feet; (2) Use cement and additives...

2014-07-01

373

40 CFR 147.305 - Requirements for all wells.  

...A Pipe analysis log; or (2) A Caliper log. (b) The owner or operator of a new injection well cased with plastic (PVC, ABS, and others) casings shall: (1) Not construct a well deeper than 500 feet; (2) Use cement and additives...

2014-07-01

374

40 CFR 147.305 - Requirements for all wells.  

Code of Federal Regulations, 2013 CFR

...A Pipe analysis log; or (2) A Caliper log. (b) The owner or operator of a new injection well cased with plastic (PVC, ABS, and others) casings shall: (1) Not construct a well deeper than 500 feet; (2) Use cement and additives...

2013-07-01

375

40 CFR 147.2104 - Requirements for all wells.  

Code of Federal Regulations, 2012 CFR

...A pipe analysis log; or (2) A caliper log. (b) The owner or operator of a new injection well cased with plastic (PVC, ABS, or others) casings shall: (1) Not construct a well deeper than 500 feet; (2) Use cement and additives...

2012-07-01

376

Comparative measurements between a new logging tool and a reference instrument  

Microsoft Academic Search

Measurements were performed on reference samples (D2O-H2O mixtures) and on highly heterogeneous rocks (Vosges sandstone) with a new logging tool designed to give access to a high spatial resolution, below 1.5 cm on the vertical scale, for a toroidal sensitive volume of 20 cm3. The results were compared to measurements obtained on a clinical magnetic resonance imaging (MRI) equipment working

Marcel Locatelli; Hervè Mathieu; Serge Bobroff; Geneviève Guillot; Bernard Zinszner

1998-01-01

377

Gel-log flocculants treat drainage  

SciTech Connect

Sedimentation ponds are often located at sites difficult to access and where electricity is not available. The problem of flocculant treatment to increase settling rates and of monitoring the system can be met by a new form of flocculant presentation in gel logs. Each log weighs 40 lbs and measures 18 in by 9 in diameter. It is wrapped in wire mesh and placed in the channel feeding the retention pond. The log gradually dissolves at a rate determined by its surface area, the water flow in contact with the gel and the water temperature. Some trial and error is necessary to achieve the correct dosage rate, but the method has been used satisfactorily for over a year.

Not Available

1982-09-01

378

Well tools  

Microsoft Academic Search

A well tool is provided which may be reciprocably moved longitudinally in well tubing for preventing formation of deposits on, and removing deposits from, the internal surfaces of the tubing. The device is movably mounted on the shank of a conventional sucker rod for reciprocating movement. It moves between a pair of vertically spaced stop surfaces on the rod. The

Barnard

1966-01-01

379

Public Wells  

USGS Multimedia Gallery

Example of wellhead plumbing typical of public wells sampled in a USGS study of 932 public wells nationwide. About 105 million people?or more than one-third of the Nation's population?receive their drinking water from one of the 140,000 public water systems across the United States that re...

2010-05-19

380

Wellness programs.  

PubMed

Befitting the economic principles underlying much of the Patient Protection and Affordable Care Act, there is a concerted push toward preventive care and personal responsibility to be as healthy as one can. This is in the form of wellness programs. The authors discuss the history and scope of wellness programs, drawing particular attention to implementation and regulatory challenges. PMID:23206647

Tjoa, Aaron; Ling, Vincent; Bender, Chris; Brittenham, Marissa; Jha, Saurabh

2012-12-01

381

MAIL LOG, program summary and specifications  

NASA Technical Reports Server (NTRS)

The summary and specifications to obtain the software package, MAIL LOG, developed for the Scout Project Automatic Data System, SPADS are provided. The MAIL LOG program has 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; and (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.

Harris, D. K.

1979-01-01

382

The scale-up behavior of coal logs for the coal log pipeline technology  

NASA Astrophysics Data System (ADS)

Coal Log Pipeline (CLP) refers to a new technology for the transportation of coal, which has been developing in the USA over the past several years, and is expected to be used on a commercial scale within the next few years. In a CLP system, coal is prepared in the form of circular cylinders, coal logs, so that the coal can be transported through an underground or overland pipeline. One of the major requirements in the CLP technology is to produce strong and durable coal logs, which can endure a long distance trip through water pipelines without breaking and with a minimum amount of weight loss. To reach this goal, research has taken place on several fabrication methods, such as compaction and extrusion, and good-quality coal logs with a diameter range of 1.8-in. to 5.4-in. have been made, using a simple compaction technique. However, for a commercial application, the size (diameter) of coal logs is expected to be much larger than the range studied in this research, therefore, the relationship in terms of quality between small and large coal logs needs to be investigated in both fabrication process and pipeline transportation operation. This dissertation describes the research work conducted on investigating scale-up behavior of coal logs during fabrication and pipeline transportation, based on the experiments from two different size coal log and pipeline loop systems. The research work covers the scaling-up effect on the strength from 1.8-in. to 5.4-in. coal logs, and on the coal log wearability during pipeline transportation from a 2-in. and a 6-in. loop.

Zhao, Bing

2000-11-01

383

Gulf of Mexico Gas Hydrate Joint Industry Project Leg II logging-while-drilling data acquisition and analysis  

USGS Publications Warehouse

One of the objectives of the Gulf of Mexico Gas Hydrate Joint Industry Project Leg II (GOM JIP Leg II) was the collection of a comprehensive suite of logging-while-drilling (LWD) data within gas-hydrate-bearing sand reservoirs in order to make accurate estimates of the concentration of gas hydrates under various geologic conditions and to understand the geologic controls on the occurrence of gas hydrate at each of the sites drilled during this expedition. The LWD sensors just above the drill bit provided important information on the nature of the sediments and the occurrence of gas hydrate. There has been significant advancements in the use of downhole well-logging tools to acquire detailed information on the occurrence of gas hydrate in nature: From using electrical resistivity and acoustic logs to identify gas hydrate occurrences in wells to where wireline and advanced logging-while-drilling tools are routinely used to examine the petrophysical nature of gas hydrate reservoirs and the distribution and concentration of gas hydrates within various complex reservoir systems. Recent integrated sediment coring and well-log studies have confirmed that electrical resistivity and acoustic velocity data can yield accurate gas hydrate saturations in sediment grain supported (isotropic) systems such as sand reservoirs, but more advanced log analysis models are required to characterize gas hydrate in fractured (anisotropic) reservoir systems. In support of the GOM JIP Leg II effort, well-log data montages have been compiled and presented in this report which includes downhole logs obtained from all seven wells drilled during this expedition with a focus on identifying and characterizing the potential gas-hydrate-bearing sedimentary section in each of the wells. Also presented and reviewed in this report are the gas-hydrate saturation and sediment porosity logs for each of the wells as calculated from available downhole well logs.

Collett, Timothy S.; Lee, Wyung W.; Zyrianova, Margarita V.; Mrozewski, Stefan A.; Guerin, Gilles; Cook, Ann E.; Goldberg, Dave S.

2012-01-01

384

Wellness Support Using Mobile Handsets  

Microsoft Academic Search

The concept of wellness mobile is a novel mobile service wherein wireless handheld devices such as cell phones are equipped with a wellness monitoring application, thereby enabling real-time self-wellness monitoring by the cell phone user. The wellness mobile will provide a safe and protective environment for an increasing cell phone user-population to help combat anti-wellness factors such as stress, fatigue,

Aravind Kailas; Chia-Chin Chong; Fujio Watanabe

2010-01-01

385

Ecological Importance of Submerged Pulpwood Logs in a Maine Reservoir  

Microsoft Academic Search

Log drives in Maine from the 1830s to 1976 left an estimated 3.6–7.2 × 10 m of pulpwood logs submerged in the Kennebec River system, principally in Wyman Lake and Indian Pond. Because favorable economics have led to commercial log salvaging, we assessed the ecological value of submerged pulpwood logs in Wyman Lake. Three species of fishes, longnose suckers Catostomus

John R. Moring; Paul D. Eiler; Mary T. Negus; Elizabeth Gibbs

1986-01-01

386

Conserving tigers Panthera tigris in selectively logged Sumatran forests  

Microsoft Academic Search

The response of most large carnivores to selective logging is poorly understood. On the one hand, selective logging may represent loss of important habitat, yet, on the other hand, selective logging may increase browse availability for a terrestrial ungulate prey base, thereby indirectly benefiting large carnivores. Using a camera trap-based sampling method, we estimate tiger density in two primary-selectively logged

Matthew Linkie; Iding Achmad Haidir; Agung Nugroho; Yoan Dinata

2008-01-01

387

1. GENERAL VIEW OF LOG POND AND BOOM FOR UNLOADING ...  

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

1. GENERAL VIEW OF LOG POND AND BOOM FOR UNLOADING CEDAR LOGS FROM TRUCKS AT LOG DUMP, ADJACENT TO MILL; TRUCKS FORMERLY USED TRIP STAKES, THOUGH FOR SAFER HANDLING OF LOGS WELDED STAKES ARE NOW REQUIRED; AS A RESULT LOADING IS NOW DONE WITH A CRANE - Lester Shingle Mill, 1602 North Eighteenth Street, Sweet Home, Linn County, OR

388

On Efficient Confidence Intervals for the Log-Normal Mean  

NASA Astrophysics Data System (ADS)

Data obtained in biomedical research is often skewed. Examples include the incubation period of diseases like HIV/AIDS and the survival times of cancer patients. Such data, especially when they are positive and skewed, is often modeled by the log-normal distribution. If this model holds, then the log transformation produces a normal distribution. We consider the problem of constructing confidence intervals for the mean of the log-normal distribution. Several methods for doing this are known, including at least one estimator that performed better than Coxxs method for small sample sizes. We also construct a modified version of Coxxs method. Using simulation, we show that, when the sample size exceeds 30, it leads to confidence intervals that have good overall properties and are better than Coxxs method. More precisely, the actual coverage probability of our method is closer to the nominal coverage probability than is the case with Coxxs method. In addition, the new method is computationally much simpler than other well-known methods.

Chami, Peter; Antoine, Robin; Sahai, Ashok

389

Live Well  

MedlinePLUS

... HIV, following a healthy diet offers several benefits. Physical Activity - Exercise offers benefits that can help you maintain ... Well Mental Health Substance Use Smoking Healthy Diet Physical Activity Family Planning Living with HIV: Travel Abroad Resources ...

390

Staying Well  

MedlinePLUS

... and Wellness Acupuncture and MS: The Basic Facts (.pdf) An exploration of what is known and not ... 2004) Download Brochure Clear Thinking About Alternative Therapies (.pdf) Facts and common misconceptions, plus practical ways to ...

391

Exploratory water-well drilling in the Houston District, Texas  

USGS Publications Warehouse

In the spring and summer of 1939 a program of exploratory drilling wad undertaken in the Houston district, Tx., in conjunction with a general initiation of the water resources of the district. The main purposes of the program were to determine the thickness and character of water-bearing sands down to a maximum depth of 2,000 feet, the chemical character of the water at different depths, and the artesian pressure and to provide additional observation wells for studying fluctuations in artesian pressure and possibilities of intrusion of salt water from the direction of the Gulf. Thirteen deep test wells, 5? inches in diameter and ranging in depth from 360 to 2,000 feet, were put down with a hydraulic rotary drill by the city of Houston. The combined drilling footage of all of the wells amounted to 17,460 feet, and their averse depth was 1,246 feet. All were electrically logged. Samples of cuttings were collected from the drilling mud after every 20 feet of drilling. In 6 of the wells sand samples were obtained by core drilling in beds at selected horizons, about 230 feet being recovered. A total of 15 samples of sand and water were obtained in 8 wells by the drill-stem method. Side-wall sampling was attempted. Six of the test holes were cased with 3? casing (inside diameter) and equipped with screens so that water-level measurements could be made and samples of water collected for chemical analyses , Selected sand samples were analyzed and tested in a field laboratory for mechanical composition, permeability, and porosity. The field and laboratory data were studied with special reference to the significance of the electrical logs. A comparison of the electrical logs of the test wells with the driller's logs shows that, on the whole, they agree remarkably well in fixing the upper and lower limits of the thicker beds of sand and clay, but that the agreement is not so close where the beds are thin. Variable results were obtained from attempts to correlate the second curve of the electrical log with the permeability and mechanical composition of the sand samples obtained by core drilling and drill-stem sampling. In the case of the core samples there was no apparent relationship between any of the three characteristics in well 3, but in well 5 a slight but distinct increase in the resistivity was accompanied by a large increase in permeability. In well 6 the resistivity in nearly every case varied with the permeability and coarseness of the samples. In well 6 the drilling mud was local clay enriched with Aquagel, whereas in wells 3 and 5 only local clay was used; the data obtained, however, are too meager to be used on a basis for even a tentative conclusion as to the effect of artificial mud on the correlations. In the 15 drill-stem sand samples the data show that, in general, the resistivity of sands having fluid content varies with but is not proportional to the permeability, but there seems to be little or no relationship between the coarseness of the sands and either the resistivity or the permeability. Studies of the relationship of the electrical logs to the salinity of the water indicate that increasing chloride is accompanied by decreasing resistivity. They suggest .that changes in the chloride content are accompanied by large changes in resistivity when the water contains less than 100 parts per million of chloride and by relatively small changes when the chloride content is over 100 parts per million. On the whole, the results of the test drilling from Houston tend to show that, although electrical logs give much information that is useful in the development of water wells, for the present at least these logs should be used in conjunction with driller's logs and drill-stem sampling of both sand and water in all the more promising sand horizons. The tests indicate that an average of 600 feet of .water-bearing sands occurs between the surface and a depth of 1,500 feet along the line of test wells we

Rose, Nicholas A.; White, W.N.; Livingston, Penn Poore

1944-01-01

392

Model Well  

NSDL National Science Digital Library

In this quick activity about pollutants and groundwater (page 2 of PDF), learners build a model well with a toilet paper tube. Learners use food coloring to simulate pollutants and observe how they can be carried by groundwater and eventually enter water sources such as wells, rivers, and streams. This activity is associated with nanotechnology and relates to linked video, DragonflyTV Nano: Water Clean-up.

Twin Cities Public Television, Inc.

2008-01-01

393

Quantitative lithostratigraphic correlation of digitized borehole-log records: Upper Glen Rose Formation, northeast Texas  

Microsoft Academic Search

Well log correlation can be enhanced by the use of quantitative expressions of curve shape similarity. In order to apply computer-assisted procedures it is necessary to consider the stratigraphic implications of the resulting correlations. To establish stratigraphic units, each individual well must first be segmented. Secondly, a procedure must be included to account for the variation of thickness between wells,

Shaw

1978-01-01

394

Securing Shareable Life-logs Reza Rawassizadeh  

E-print Network

. Sensors are the core components of the life-logs and they are used to sense contextual information. For instance a user can share content, find new friends based on the shared content (common interests) and stay information with a social community might be harmful. Allen [13] described that using life

395

Wideband Planar Log-Periodic Antenna  

Microsoft Academic Search

A compact planar wideband microstrip antenna is introduced. The antenna is a log-periodic antenna with 7 dipole elements. The antenna is designed to function in the frequency range of 500 to 700 MHz. It has a dimension of 268 mm by 145 mm by 3 mm. The matching is better than -10 dB in the working bandwidth. The proposed antenna

M. M. Tajdini; M. Shahabadi

2007-01-01

396

A planar log-periodic antenna  

Microsoft Academic Search

A planar log-periodic antenna structure that has radiation characteristics similar to those of a half-wave dipole has been found. The bandwidth can be as large as desired, and antennas can be easily fabricated by using printed circuit techniques. When fed with a suitable balun, VSWR's lower than 1.8:1 can be obtained over a wide-frequency band.

K. Keen

1974-01-01

397

Mutual coupling between log-periodic antennas  

Microsoft Academic Search

Numerical techniques are used for the analysis of mutual coupling in arrays of log-periodic dipole antennas. The analysis is formulated in terms of impedance and admittance matrices for the dipole and transmission line networks. Approximations are made to allow the solution for moderately sized arrays to be practical with the existing generation of computers. Antenna patterns for the array are

R. Kyle

1970-01-01

398

Stagger tuned microstrip log-periodic antenna  

Microsoft Academic Search

Log-periodic dipole antennas (LPDA) have been extensively used since 1960 when their properties were described by Isbell, whose work was followed by the detailed analysis of Carrel (1961). Progress in microwave integrated circuits in the last decade has created a demand for compact antennas, along with the requirement that the systems have a large bandwidth. The approach for broadband configuration

Rajesh Kakkar; Girish Kumar

1996-01-01

399

[Human development and log-periodic law].  

PubMed

We suggest applying the log-periodic law formerly used to describe various crisis phenomena, in biology (evolutionary leaps), inorganic systems (earthquakes), societies and economy (economic crisis, market crashes) to the various steps of human ontogeny. We find a statistically significant agreement between this model and the data. PMID:12187644

Cash, Roland; Chaline, Jean; Nottale, Laurent; Grou, Pierre

2002-05-01

400

An Effective System for Mining Web Log  

Microsoft Academic Search

The WWW provides a simple yet effective media for users to search, browse, and retrieve information in the Web. Web log mining is a promising tool to study user behaviors, which could further benefit web-site designers with better organization and services. Although there are many existing systems that can be used to analyze the traversal path of web-site visitors, their

Zhenglu Yang; Yitong Wang; Masaru Kitsuregawa

2006-01-01

401

Discussion logs for h-childhood  

NSDL National Science Digital Library

This new moderated H-Net discussion list seeks to link international scholars studying the history of childhood and youth in all regions and time periods. Resources available at the site include discussion threads, message logs, a review project, and academic announcements.

402

ABUNDANCE THEOREM FOR SEMI LOG CANONICAL THREEFOLDS  

E-print Network

. The abundance theorem for semi log canonical surfaces was proved in [12, Chapter 8, 12] by L.­Y. Fong, S. Keel abundance theorem for threefolds proved by S. Keel, K. Matsuki and J. McKernan (See [10]). According to them.1)) and we prove the finiteness of them for curves and surfaces. It plays an important role in our proof

403

29 CFR 1910.266 - Logging operations.  

Code of Federal Regulations, 2010 CFR

...protection, such as heavy-duty logging boots that are waterproof or water repellant, cover...of part 1910. (5) Environmental conditions. All work...the fall of a tree, heavy rain or snow, extreme...contact with poisonous plants or animals....

2010-07-01

404

Modelling tropical forests response to logging  

NASA Astrophysics Data System (ADS)

Tropical rainforests are among the most threatened ecosystems by large-scale fragmentation due to human activity such as heavy logging and agricultural clearance. Although, they provide crucial ecosystem goods and services, such as sequestering carbon from the atmosphere, protecting watersheds and conserving biodiversity. In several countries forest resource extraction has experienced a shift from clearcutting to selective logging to maintain a significant forest cover and understock of living biomass. However the knowledge on the short and long-term effects of removing selected species in tropical rainforest are scarce and need to be further investigated. One of the main effects of selective logging on forest dynamics seems to be the local disturbance which involve the invasion of open space by weed, vines and climbers at the expense of the late-successional state cenosis. We present a simple deterministic model that describes the dynamics of tropical rainforest subject to selective logging to understand how and why weeds displace native species. We argue that the selective removal of tallest tropical trees carries out gaps of light that allow weeds, vines and climbers to prevail on native species, inhibiting the possibility of recovery of the original vegetation. Our results show that different regime shifts may occur depending on the type of forest management adopted. This hypothesis is supported by a dataset of trees height and weed/vines cover that we collected from 9 plots located in Central and West Africa both in untouched and managed areas.

Cazzolla Gatti, Roberto; Di Paola, Arianna; Valentini, Riccardo; Paparella, Francesco

2013-04-01

405

Gentle Logging System Evaluation (PARTICIPANTS' QUESTIONNAIRE REPORT)  

E-print Network

Raymond O. Miller and William E. Cook 1 Abstract Five, new, cut-to-length harvesting systems wereGentle Logging System Evaluation (PARTICIPANTS' QUESTIONNAIRE REPORT) November 26, 2001 Raymond O. Miller William E. Cook Published by Michigan State University Upper Peninsula Tree Improvement Center

406

Activating Metacognition through Online Learning Log (OLL)  

ERIC Educational Resources Information Center

This study aims to investigate the activation process of metacognition of learners who systematically reflect on their learning using Online Learning Logs (OLL) which were designed to encourage them to think about learning. The study is qualitative and attempts to identify the metacognitive strategies of learners and their attitudes towards OLL.…

Kurt, Mustafa

2007-01-01

407

MAIL LOG, program theory, volume 2  

NASA Technical Reports Server (NTRS)

Information relevant to the MAIL LOG program theory is documented. The L-files for mail correspondence, design information release/report, and the drawing/engineering order are given. In addition, sources for miscellaneous external routines and special support routines are documented along with a glossary of terms.

Harris, D. K.

1979-01-01

408

Indonesia to fight illegal logging Kurniawan Hari  

E-print Network

Indonesia to fight illegal logging Kurniawan Hari The government should set up a task force to deal another $8.1 billion. "Indonesia's economy will collapse if these evil practices are not stopped," Ermaya in the current fiscal year and was three times Indonesia's foreign debt budget. Commission members said the sand

409

USGS Training on Borehole Geophysical Logging  

USGS Multimedia Gallery

A USGS hydrologist holds an electromagnetic induction borehole logging tool while the tool is calibrated. The hydrologist was participating in a USGS class on how to use electromagnetic induction geophysical methods for groundwater investigations, conducted by the USGS Office of Groundwater Branch o...

2009-05-01

410

Bulk density logging with high-energy gammas produced by fast neutron reactions with formation oxygen atoms  

Microsoft Academic Search

Borehole logging for formation density has been an important geophysical measurement for many years in the minerals, geotechnical, oil, and natural gas industries. The conventional gamma-gamma backscatter method has performed well in open, smooth boreholes. However, the method has limited depth of investigation and has not been quantitative in cased holes. A new method of logging earth formations for bulk

Robert D. Wilson; Rust Geotech

1995-01-01

411

Recovery Efficiency Test Project: Phase 1, Activity report. Volume 1: Site selection, drill plan preparation, drilling, logging, and coring operations  

SciTech Connect

The recovery Efficiency Test well project addressed a number of technical issues. The primary objective was to determine the increased efficiency gas recovery of a long horizontal wellbore over that of a vertical wellbore and, more specifically, what improvements can be expected from inducing multiple hydraulic fractures from such a wellbore. BDM corporation located, planned, and drilled a long radius turn horizontal well in the Devonian shale Lower Huron section in Wayne County, West Virginia, demonstrating that state-of-the-art technology is capable of drilling such wells. BDM successfully tested drilling, coring, and logging in a horizontal well using air as the circulating medium; conducted reservoir modeling studies to protect flow rates and reserves in advance of drilling operations; observed two phase flow conditions in the wellbore not observed previously; cored a fracture zone which produced gas; observed that fractures in the core and the wellbore were not systematically spaced (varied from 5 to 68 feet in different parts of the wellbore); observed that highest gas show rates reported by the mud logger corresponded to zone with lowest fracture spacing (five feet) or high fracture frequency. Four and one-half inch casting was successfully installed in the borehole and was equipped to isolate the horizontal section into eight (8) zones for future testing and stimulation operations. 6 refs., 48 figs., 10 tabs.

Overbey, W.K. Jr.; Carden, R.S.; Kirr, J.N.

1987-04-01

412

I. (1) (log(|g(x)|)) = g(x) g(x) , (log(logx)) = 1  

E-print Network

A (5/9) I. (1) (log(|g(x)|)) = g(x) g(x) , (log(logx)) = 1 logx(logx) = 1 xlogx (2) ( h(x) g(x) ) = g(x)h(x)-g(x)h(x) g(x)2 , g(x) = e-x + 1, h(x) = ex + 1 ( ex + 1 e-x + 1 ) = (e-x + 1)(ex + 1) - (e-x + 1)(ex + 1) (e-x + 1)2 = 2 + ex + e-x (e-x + 1)2 (3) (1) , (log( x + 1 + x + 2)) = 1 x + 1 + x

Ochiai, Tadashi

413

Monitoring well  

DOEpatents

A monitoring well is described which includes: a conduit defining a passageway, the conduit having a proximal and opposite, distal end; a coupler connected in fluid flowing relationship with the passageway; and a porous housing borne by the coupler and connected in fluid flowing relation thereto. 8 figs.

Hubbell, J.M.; Sisson, J.B.

1999-06-29

414

All's WELL.  

ERIC Educational Resources Information Center

Describes the Workforce Education and Lifelong Learning (WELL) program at the Ohio State University, ranked as the number one school for vocational-technical education by U.S. News & World report for the last three years. Includes a list of the top schools in the field. (JOW)

Husain, Dilshad D.

1999-01-01

415

Anisotropic anomalous diffusion modulated by log-periodic oscillations.  

PubMed

We introduce finite ramified self-affine substrates in two dimensions with a set of appropriate hopping rates between nearest-neighbor sites where the diffusion of a single random walk presents an anomalous anisotropic behavior modulated by log-periodic oscillations. The anisotropy is revealed by two different random-walk exponents ?(x) and ?(y) in the x and y directions, respectively. The values of these exponents as well as the periods of the oscillations are obtained analytically and confirmed by Monte Carlo simulations. PMID:23005367

Padilla, L; Mártin, H O; Iguain, J L

2012-07-01

416

Anisotropic anomalous diffusion modulated by log-periodic oscillations  

NASA Astrophysics Data System (ADS)

We introduce finite ramified self-affine substrates in two dimensions with a set of appropriate hopping rates between nearest-neighbor sites where the diffusion of a single random walk presents an anomalous anisotropic behavior modulated by log-periodic oscillations. The anisotropy is revealed by two different random-walk exponents ?x and ?y in the x and y directions, respectively. The values of these exponents as well as the periods of the oscillations are obtained analytically and confirmed by Monte Carlo simulations.

Padilla, L.; Mártin, H. O.; Iguain, J. L.

2012-07-01

417

Monitoring well  

DOEpatents

The present invention relates to a monitoring well which includes an enclosure defining a cavity and a water reservoir enclosed within the cavity and wherein the reservoir has an inlet and an outlet. The monitoring well further includes a porous housing borne by the enclosure and which defines a fluid chamber which is oriented in fluid communication with the outlet of the reservoir, and wherein the porous housing is positioned in an earthen soil location below-grade. A geophysical monitoring device is provided and mounted in sensing relation relative to the fluid chamber of the porous housing; and a coupler is selectively moveable relative to the outlet of reservoir to couple the porous housing and water reservoir in fluid communication. An actuator is coupled in force transmitting relation relative to the coupler to selectively position the coupler in a location to allow fluid communication between the reservoir and the fluid chamber defined by the porous housing.

Hubbell, Joel M. (Idaho Falls, ID); Sisson, James B. (Idaho Falls, ID)

2002-01-01

418

Log-Periodiska Dipolantenner i Enkla Arrayer (Log-Periodic Dipole Antennas in Simple Arrays).  

National Technical Information Service (NTIS)

The report gives a theoretical description of log-periodic dipole antennas (LPDA) including some practical examples. The possibility of designing an antenna structure which is independent of frequency has been investigated. There are various geometrical c...

A. C. Vogel

1991-01-01

419

Strategy Guideline: HVAC Equipment Sizing  

SciTech Connect

The heating, ventilation, and air conditioning (HVAC) system is arguably the most complex system installed in a house and is a substantial component of the total house energy use. A right-sized HVAC system will provide the desired occupant comfort and will run efficiently. This Strategy Guideline discusses the information needed to initially select the equipment for a properly designed HVAC system. Right-sizing of an HVAC system involves the selection of equipment and the design of the air distribution system to meet the accurate predicted heating and cooling loads of the house. Right-sizing the HVAC system begins with an accurate understanding of the heating and cooling loads on a space; however, a full HVAC design involves more than just the load estimate calculation - the load calculation is the first step of the iterative HVAC design procedure. This guide describes the equipment selection of a split system air conditioner and furnace for an example house in Chicago, IL as well as a heat pump system for an example house in Orlando, Florida. The required heating and cooling load information for the two example houses was developed in the Department of Energy Building America Strategy Guideline: Accurate Heating and Cooling Load Calculations.

Burdick, A.

2012-02-01

420

Equipment Operational Requirements  

SciTech Connect

The Iraq Department of Border Enforcement is rich in personnel, but poor in equipment. An effective border control system must include detection, discrimination, decision, tracking and interdiction, capture, identification, and disposition. An equipment solution that addresses only a part of this will not succeed, likewise equipment by itself is not the answer without considering the personnel and how they would employ the equipment. The solution should take advantage of the existing in-place system and address all of the critical functions. The solutions are envisioned as being implemented in a phased manner, where Solution 1 is followed by Solution 2 and eventually by Solution 3. This allows adequate time for training and gaining operational experience for successively more complex equipment. Detailed descriptions of the components follow the solution descriptions. Solution 1 - This solution is based on changes to CONOPs, and does not have a technology component. It consists of observers at the forts and annexes, forward patrols along the swamp edge, in depth patrols approximately 10 kilometers inland from the swamp, and checkpoints on major roads. Solution 2 - This solution adds a ground sensor array to the Solution 1 system. Solution 3 - This solution is based around installing a radar/video camera system on each fort. It employs the CONOPS from Solution 1, but uses minimal ground sensors deployed only in areas with poor radar/video camera coverage (such as canals and streams shielded by vegetation), or by roads covered by radar but outside the range of the radar associated cameras. This document provides broad operational requirements for major equipment components along with sufficient operational details to allow the technical community to identify potential hardware candidates. Continuing analysis will develop quantities required and more detailed tactics, techniques, and procedures.

Greenwalt, B; Henderer, B; Hibbard, W; Mercer, M

2009-06-11

421

Contribution of logging data to sedimentology and stratigraphy. [Electrofacies  

SciTech Connect

A technique has been developed using multivariate analysis of logging data to give a high-resolution sedimentological description of any sequence of formations. The number of different logs and their range allow determination of many of the physical characteristics of the rock. The definition of a lithofacies has been extended by introducing the concept of an electrofacies, constructed on the basis of all the logging data at any depth interval. Each logging datum is considered a descriptor for purposes of establishing electrofacies in a logged interval. Once established, electrofacies then can be correlated with actual geologic facies, if the logged interval has been cored. 23 refs.

Serra, O.; Abbott, H.T.

1982-02-01

422

Equipment Management Manual  

NASA Technical Reports Server (NTRS)

The NASA Equipment Management Manual (NHB 4200.1) is issued pursuant to Section 203(c)(1) of the National Aeronautics and Space Act of 1958, as amended (42 USC 2473), and sets forth policy, uniform performance standards, and procedural guidance to NASA personnel for the acquisition, management, and use of NASA-owned equipment. This revision is effective upon receipt. This is a controlled manual, issued in loose-leaf form, and revised through page changes. Additional copies for internal use may be obtained through normal distribution.

1992-01-01

423

No chiral truncation of quantum log gravity?  

E-print Network

At the classical level, chiral gravity may be constructed as a consistent truncation of a larger theory called log gravity by requiring that left-moving charges vanish. In turn, log gravity is the limit of topologically massive gravity (TMG) at a special value of the coupling (the chiral point). We study the situation at the level of linearized quantum fields, focussing on a unitary quantization. While the TMG Hilbert space is continuous at the chiral point, the left-moving Virasoro generators become ill-defined and cannot be used to define a chiral truncation. In a sense, the left-moving asymptotic symmetries are spontaneously broken at the chiral point. In contrast, in a non-unitary quantization of TMG, both the Hilbert space and charges are continuous at the chiral point and define a unitary theory of chiral gravity at the linearized level.

Tomas Andrade; Donald Marolf

2009-09-03

424

The Nevada Test Site neutron log calibrator  

SciTech Connect

A new calibrator for neutron logs in large-diameter holes has been built at the Nevada Test Site. It consists of two cylinders, each made of six wedge-shaped cells. The outside diameter of each cylinder is 4.8 m, and the inside diameter is 2.4 m; the height is 2.3 m. The cells were filled with mixtures of hydrated alumina, tabular alumina, sand, and water to achieve a large range of bulk density and hydrogen index. A new calibration algorithm, using three-dimensional interpolation in hydrogen index-gap-density space has been developed to determine hydrogen index from log data. There is evidence that the new algorithm is slightly more accurate than the previous algorithm.

Hearst, J.R.

1994-02-01

425

NetBem: business equipment energy monitoring through network auditing  

Microsoft Academic Search

Modern office buildings are fully equipped and furnished spaces with arrangements including networked business equipment, such as PC-class machines, copiers, wireless routers and fax machines, and other electrical equipment such as home appliances e.g. coffee machines, and appliances for environmental comfort e.g. electric heaters. The unique characteristics of networked business equipment are well-defined usage pattern, low-power current draw, and connectivity

A. Schoofs; A. Sintoni; A. G. Ruzzelli; G. M. P. O'Hare

2010-01-01

426

Wideband quasi-log-periodic microstrip antenna  

Microsoft Academic Search

The paper describes a new design method for a wideband array of log-periodically sealed microstrip resonator antennas. The radiating elements are series-fed by a simple coplanar microstrip network. This network consists of an open-circuited feed line with a branch line connected to each radiating element. Both a network and a radiating model for the complete structure are explained. These models

H. Pues; J. Bogaers; R. Pieck; A. van de Capelle

1981-01-01

427

Using Web Logs in the Science Classroom  

ERIC Educational Resources Information Center

As educators we must ask ourselves if we are meeting the needs of today's students. The science world is adapting to our ever-changing society; are the methodology and philosophy of our educational system keeping up? In this article, you'll learn why web logs (also called blogs) are an important Web 2.0 tool in your science classroom and how they…

Duplichan, Staycle C.

2009-01-01

428

CORRELATOR 5.2 - A program for interactive lithostratigraphic correlation of wireline logs  

USGS Publications Warehouse

The limited radius of investigation of petrophysical measurements made in boreholes and the relatively large distances between wells result in an incomplete sensing of the subsurface through well logging. CORRELATOR is a program for estimating geological properties between logged boreholes. An initial and fundamental step is the lithostratigraphic correlation of logs in different wells. The method employed by the program closely emulates the process of visual inspection used by experienced subsurface geologists in manual correlation. Mathematically, the determination of lithostratigraphical equivalence is based on the simultaneous assessment of similarity in shale content, similarity in the patterns of vertical variation in a petrophysical property that is measured with high vertical resolution, and spatial consistency of stratigraphic relationships as determined by an expert system. Multiple additional options for processing log readings allow maximization in the extraction of information from pairs of logs per well and great flexibility in the final display of results in the form of cross sections and dip diagrams. ?? 2004 Elsevier Ltd. All rights reserved.

Olea, R.A.

2004-01-01

429

Well apparatus  

SciTech Connect

This patent describes an apparatus comprising: a well packer having at least two flow ways therethrough, a conduit providing a first control pressure, vent valve means connected to the conduit and controlling one of the flow ways and having a flow member reciprocal in both directions between open and closed positions for multiple cycles in response to a first control pressure in the conduit. The valve means remains closed in the absence of first control pressure and when subjected to a second ambient pressure less than a selected value, and kill valve means associated with the packer and vent valve and in combination with one of the flow ways, the kill valve means opening in response to a second ambient pressure above the selected value.

Echols, R.H.; Patel, B.H.; Renfroe, J.B. Jr.

1986-11-25

430

Chiral Gravity, Log Gravity and Extremal CFT  

E-print Network

We show that the linearization of all exact solutions of classical chiral gravity around the AdS3 vacuum have positive energy. Non-chiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity-- the theory with logarithmically relaxed boundary conditions --has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic CFT. Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We normally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.

Alexander Maloney; Wei Song; Andrew Strominger

2009-03-26

431

Quantitative Literacy: Working with Log Graphs  

NASA Astrophysics Data System (ADS)

The need for working with and understanding different types of graphs is a common occurrence in everyday life. Examples include anything having to do investments, being an educated juror in a case that involves evidence presented graphically, and understanding many aspect of our current political discourse. Within a science class graphs play a crucial role in presenting and interpreting data. In astronomy, where the range of graphed values is many orders of magnitude, log-axes must be used and understood. Experience shows that students do not understand how to read and interpret log-axes or how they differ from linear. Alters (1996), in a study of college students in an algebra-based physics class, found little understanding of log plotting. The purpose of this poster is to show the method and progression I have developed for use in my “ASTRO 101” class, with the goal being to help students better understand the H-R diagram, mass-luminosity relationship, and digital spectra.

Shawl, S.

2013-04-01

432

Precision pressure/temperature logging tool  

SciTech Connect

Past memory logging tools have provided excellent pressure/temperature data when used in a geothermal environment, and they are easier to maintain and deploy than tools requiring an electric wireline connection to the surface. However, they are deficient since the tool operator is unaware of downhole conditions that could require changes in the logging program. Tools that make ``decisions`` based on preprogrammed scenarios can partially overcome this difficulty, and a suite of such memory tools has been developed at Sandia National Laboratories. The first tool, which forms the basis for future instruments, measures pressure and temperature. Design considerations include a minimization of cost while insuring quality data, size compatibility with diamond-cored holes, operation in holes to 425 C (800 F), transportability by ordinary passenger air service, and ease of operation. This report documents the development and construction of the pressure/temperature tool. It includes: (1) description of the major components; (2) calibration; (3) typical logging scenario; (4) tool data examples; and (5) conclusions. The mechanical and electrical drawings, along with the tool`s software, will be furnished upon request.

Henfling, J.A.; Normann, R.A.

1998-01-01

433

The Dry Eye Disease Activity Log Study  

PubMed Central

Prolonged visually stressful activities aggravate dry eye disease (DED). The duration spent on such activities and their relationship with DED clinical features were investigated. Patients completed an activity log as they performed their usual activities over 1 typical rest day and 1 typical work day. The log included time spent in an air-conditioned environment, windy environment, driving, watching television, computer use, reading, watching a movie in the theatre, and wearing contact lens. Average daily activity hours were calculated and correlated with clinical features of DED. Thirty-five logs were returned. Positive correlation was found between watching television and episodic blurred vision (P < 0.01). Computer use was negatively correlated with episodic blur vision, burning sensation, and gritty sensation (P < 0.05). Negative correlation was found between time spent in windy environments, driving, reading, and certain DED symptoms (P < 0.05). Reading correlated positively with severity of corneal fluorescein staining and reduced Schirmer's values (P < 0.03). The use of air conditioning correlated negatively with episodic blur vision but positively with visual blurring that improves with lubricants (P = 0.02). This study is the first to evaluate the relationship between time spent on DED-aggravating activities and DED clinical features. Negative correlations between certain activities and DED symptoms suggest an unconscious modification of lifestyle to alleviate symptoms. PMID:23193384

Iyer, Jayant V.; Lee, Sze-Yee; Tong, Louis

2012-01-01

434

The dry eye disease activity log study.  

PubMed

Prolonged visually stressful activities aggravate dry eye disease (DED). The duration spent on such activities and their relationship with DED clinical features were investigated. Patients completed an activity log as they performed their usual activities over 1 typical rest day and 1 typical work day. The log included time spent in an air-conditioned environment, windy environment, driving, watching television, computer use, reading, watching a movie in the theatre, and wearing contact lens. Average daily activity hours were calculated and correlated with clinical features of DED. Thirty-five logs were returned. Positive correlation was found between watching television and episodic blurred vision (P < 0.01). Computer use was negatively correlated with episodic blur vision, burning sensation, and gritty sensation (P < 0.05). Negative correlation was found between time spent in windy environments, driving, reading, and certain DED symptoms (P < 0.05). Reading correlated positively with severity of corneal fluorescein staining and reduced Schirmer's values (P < 0.03). The use of air conditioning correlated negatively with episodic blur vision but positively with visual blurring that improves with lubricants (P = 0.02). This study is the first to evaluate the relationship between time spent on DED-aggravating activities and DED clinical features. Negative correlations between certain activities and DED symptoms suggest an unconscious modification of lifestyle to alleviate symptoms. PMID:23193384

Iyer, Jayant V; Lee, Sze-Yee; Tong, Louis

2012-01-01

435

Automatic fracture density update using smart well data and artificial neural networks  

NASA Astrophysics Data System (ADS)

This paper presents a new methodology to continuously update and improve fracture network models. We begin with a hypothetical model whose fracture network parameters and geological information are known. After generating the "exact" fracture network with known characteristics, the data were exported to a reservoir simulator and simulations were run over a period of time. Intelligent wells equipped with downhole multiple pressure and flow sensors were placed throughout the reservoir and put into production. These producers were completed in different fracture zones to create a representative pressure and production response. We then considered a number of wells of which static (cores and well logs) and dynamic (production) data were used to model well fracture density. As new wells were opened, historical static and dynamic data from previous wells and static data from the new wells were used to update the fracture density using Artificial Neural Networks (ANN). The accuracy of the prediction model depends significantly on the representation of the available data of the existing fracture network. The importance of conventional data (surface production data) and smart well data prediction capability was also investigated. Highly sensitive input data were selected through a forward selection scheme to train the ANN. Well geometric locations were included as a new link in the ANN regression process. Once the relationship between fracture network parameters and well performance data was established, the ANN model was used to predict fracture density at newly drilled locations. Finally, an error analysis through a correlation coefficient and percentage absolute relative error performance was performed to examine the accuracy of the proposed inverse modeling methodology. It was shown that fracture dominated production performance data collected from both conventional and smart wells allow for automatically updating the fracture network model. The proposed technique helps in generating another - readily available at no cost - data source for fracture characterization as a supplement to limited 1D data obtained from well logs and cores.

Al-Anazi, A.; Babadagli, T.

2010-03-01

436

Annual Logging Symposium, June 21-24, 2009 HISTORY MATCHING OF MULTIPHASE-FLOW FORMATION-  

E-print Network

-FLOW FORMATION- TESTER MEASUREMENTS ACQUIRED WITH FOCUSED-SAMPLING PROBES IN DEVIATED WELLS Renzo Angeles, Carlos International E&P Copyright 2009, held jointly by the Society of Petrophysicists and Well Log Analysts (SPWLA challenging. The combination of miscibility (between mud-filtrate and in-situ oil) and non-standard probe

Torres-Verdín, Carlos

437

Determining Heterogeneity of Lithologic Units from Flow Logs and Aquifer Tests  

Microsoft Academic Search

Hydraulic conductivities of volcanic and carbonate lithologic units at the Nevada Test Site were estimated from flow logs and single-well aquifer tests. Borehole flow and drawdown were interpreted with results from radial, axisymmetric flow models. This integrated approach was necessitated by complex well completions and heterogeneous aquifers that created vertical flow in the annular space and aquifer that surrounded the

C. Garcia; K. J. Halford; R. J. Laczniak

2008-01-01

438

Confidence Intervals for the Mean of a Log-Normal Distribution  

ERIC Educational Resources Information Center

Methods for calculating confidence intervals for the mean are reviewed for the case where the data come from a log-normal distribution. In a simulation study it is found that a variation of the method suggested by Cox works well in practice. An approach based on Generalized confidence intervals also works well. A comparison of our results with…

Olsson, Ulf

2005-01-01

439

Automatic intelligibility test equipment  

Microsoft Academic Search

The report describes an Automatic Intelligibility Test equipment (AITE) which automatically measures the word intelligibility of a digital voice communication link. The system consists of a Nova 820 mini computer, AID converter, teletype unit (ASR-33), tape recorder, high speed paper tape reader and punch set, and the phoneme test sequence. The phoneme test sequence is recorded on audio tape which

D. J. Jurenko

1974-01-01

440

The EQUIP Program  

ERIC Educational Resources Information Center

Youth who present anti-social behavior need powerful interventions that strengthen empathy, counter negative peer influence, and challenge thinking errors. This article recaps some key points about EQUIP, a Positive Peer Culture (PPC)-based cognitive behavioral intervention program for behaviorally at-risk youth, and notes how the program has…

Gibbs, John C.; Potter, Granville Bud; DiBiase, Ann-Marie; Devlin, Renee

2008-01-01

441

Lennox - Student Training Equipment.  

ERIC Educational Resources Information Center

Presents a series of demonstration units designed by Lennox Industries for the purpose of training students to become familiar with Lennox mechanical equipment. Demonstrators are designed to present technical information in a clear simplified manner thus reducing frustration for the beginning trainee. The following demonstrators are available--(1)…

Lennox Industries, Inc., Marshalltown, IA.

442

Basic Engineer Equipment Mechanic.  

ERIC Educational Resources Information Center

This student guide, one of a series of correspondence training courses designed to improve the job performance of members of the Marine Corps, deals with the skills needed by basic engineer equipment mechanics. Addressed in the four individual units of the course are the following topics: mechanics and their tools (mechanics, hand tools, and power…

Marine Corps Inst., Washington, DC.

443

Homemade Innovative Play Equipment.  

ERIC Educational Resources Information Center

Sponsored by the Title III Elementary and Secondary Education Act Project "Discovery Outdoor Education", this guide is a collection of inexpensive, innovative, homemade equipment and devices for physical activities. Although designed for the impaired, disabled, and handicapped, these materials are adaptable to and applicable for groups and…

Pearson, L. Roger, Comp.

444

Engineer Equipment Chief.  

ERIC Educational Resources Information Center

This student guide, one of a series of correspondence training courses designed to improve the job performance of members of the Marine Corps, deals with the skills needed by engineer equipment chiefs. Addressed in the five individual units of the course are the following topics: construction management (planning, scheduling, and supervision);…

Marine Corps Inst., Washington, DC.

445

Fire protection equipment includes  

E-print Network

The purpose of these requirements is to ensure the adequate provision and operability of fire protection equipment. They cover design and construction review, maintenance, and inspection. They apply to workers and supervisors, building and area managers, the SLAC fire marshal, Fire Department, and Facilities Department.

unknown authors

446

Dairy Equipment Lubrication  

NASA Technical Reports Server (NTRS)

Lake To Lake Dairy Cooperative, Manitowoc, Wisconsin, operates four plants in Wisconsin for processing milk, butter and cheese products from its 1,300 member farms. The large co-op was able to realize substantial savings by using NASA information for improved efficiency in plant maintenance. Under contract to Marshall Space Flight Center, Midwest Research Institute compiled a handbook consolidating information about commercially available lubricants. The handbook details chemical and physical properties, applications, specifications, test procedures and test data for liquid and solid lubricants. Lake To Lake's plant engineer used the handbook to effect savings in maintenance labor and materials costs by reducing the number of lubricants used on certain equipment. Strict U.S. Department of Agriculture and Food and Drug Administration regulations preclude lubrication changes n production equipment, but the co-op's maintenance chief was able to eliminate seven types of lubricants for ancillary equipment, such as compressors and high pressure pumps. Handbook data enabled him to select comparable but les expensive lubricants in the materials consolidation process, and simplified lubrication schedules and procedures. The handbook is in continuing use as a reference source when a new item of equipment is purchased.

1978-01-01

447

Total equipment parts configuration  

SciTech Connect

Florida Power Lights's (FP L's) Turkey Point units were built prior to the establishment of American Society of Mechanical Engineers' Sec. III requirements. Since that time, FP L has voluntarily committed to procuring some spare and replacement parts in compliance with the ordering requirements of ASME Sec. III. New subsystems were designed according to ASME Sec. III requirements. In 1978, 10CFR21 of the Code of Federal Regulations was federally mandated. Environmental qualification concerns and the Three Mile Island incident further complicated the stocking and ordering of spare and replacement parts. Turkey Point assembled a team of quality assurance, quality control, and engineering people and obtained permission to directly access the store department computer so that catalog descriptions could be quickly made available for use by the plant. The total equipment parts configuration (TEPC) system was designed and developed under the direction of the procurement document review team at the Turkey Point nuclear plant. The system is a network of related computer data bases that identifies the equipment at the plant. The equipment (or components that make up a piece of equipment) is identified by a tag/component code system. Each component is further broken down by the manufacturer's parts list or bill of material. A description of the data available to the user, the ways these data can be accessed and displayed, and a description of the data bases and their relation to each other are summarized in this paper.

Ferrare, J.; Panzani, F.

1989-01-01

448

Log-periodic route to fractal functions.  

PubMed

Log-periodic oscillations have been found to decorate the usual power-law behavior found to describe the approach to a critical point, when the continuous scale-invariance symmetry is partially broken into a discrete-scale invariance symmetry.