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1

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

NASA Astrophysics Data System (ADS)

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

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

2011-12-01

2

Chemical analysis of water samples and geophysical logs from cored test holes drilled in the central Oklahoma Aquifer, Oklahoma  

USGS Publications Warehouse

Chemical analyses of water from eight test holes and geophysical logs for nine test holes drilled in the Central Oklahoma aquifer are presented. The test holes were drilled to investigate local occurrences of potentially toxic, naturally occurring trace substances in ground water. These trace substances include arsenic, chromium, selenium, residual alpha-particle activities, and uranium. Eight of the nine test holes were drilled near wells known to contain large concentrations of one or more of the naturally occurring trace substances. One test hole was drilled in an area known to have only small concentrations of any of the naturally occurring trace substances. Water samples were collected from one to eight individual sandstone layers within each test hole. A total of 28 water samples, including four duplicate samples, were collected. The temperature, pH, specific conductance, alkalinity, and dissolved-oxygen concentrations were measured at the sample site. Laboratory determinations included major ions, nutrients, dissolved organic carbon, and trace elements (aluminum, arsenic, barium, beryllium, boron, cadmium, chromium, hexavalent chromium, cobalt, copper, iron, lead, lithium, manganese, mercury, molybdenum, nickel, selenium, silver, strontium, vanadium, and zinc). Radionuclide activities and stable isotope d values also were determined, including: gross-alpha-particle activity, gross-beta-particle activity, radium-226, radium-228, radon-222, uranium-234, uranium-235, uranium-238, total uranium, carbon-13/carbon-12, deuterium/hydrogen-1, oxygen-18/oxygen-16, and sulfur-34/sulfur-32. Additional analyses of arsenic and selenium species are presented for selected samples as well as analyses of density and iodine for two samples, tritium for three samples, and carbon-14 for one sample. Geophysical logs for most test holes include caliper, neutron, gamma-gamma, natural-gamma logs, spontaneous potential, long- and short-normal resistivity, and single-point resistance. Logs for test-hole NOTS 7 do not include long- and short-normal resistivity, spontaneous-potential, or single-point resistivity. Logs for test-hole NOTS 7A include only caliper and natural-gamma logs.

Schlottmann, Jamie L.; Funkhouser, Ron A.

1991-01-01

3

A Model of the Chicxulub Impact Basin Based on Evaluation of Geophysical Data, Well Logs, and Drill Core Samples  

NASA Technical Reports Server (NTRS)

Abundant evidence now shows that the buried Chicxulub structure in northern Yucatan, Mexico, is indeed the intensely sought-after source of the ejecta found world-wide at the Cretaceous-Tertiary (K/T) boundary. In addition to large-scale concentric patterns in gravity and magnetic data over the structure, recent analyses of drill-core samples reveal a lithological assemblage similar to that observed at other terrestrial craters. This assemblage comprises suevite breccias, ejecta deposit breccias (Bunte Breccia equivalents), fine-grained impact melt rocks, and melt-matrix breccias. All these impact-produced lithologies contain diagnostic evidence of shock metamorphism, including planar deformation features in quartz, feldspar, and zircons; diaplectic glasses of quartz and feldspar; and fused mineral melts and whole-rock melts. In addition, elevated concentrations of Ir, Re, and Os, in meteoritic relative proportions, have been detected in some melt-rock samples from the center of the structure. Isotopic analyses, magnetization of melt-rock samples, and local stratigraphic constraints identify this crater as the source of K/T boundary deposits.

Sharpton, Virgil L.; Marin, Luis E.; Carney, John D.; Lee, Scott; Ryder, Graham; Schuraytz, Benjamin C.; Sikora, Paul; Spudis, Paul D.

1996-01-01

4

New Drilling Core Facility  

NASA Astrophysics Data System (ADS)

A new Department of Energy (DOE) facility, dedicated to curating samples, cores, and other materials obtained under the Continental Scientific Drilling Program (CSDP), will become available early in 1985 in Grand Junction, Colo. The facility will be operated by DOE in cooperation with the U.S. Geological Survey and the National Science Foundation. The three agencies are working together on continental scientific drilling in the United States under their formally adopted Interagency Accord on Scientific Drilling.From the time they are gathered at the drill site, these samples and routine logging data will be protected under Curatorial Policy Guidelines and Procedures. These guidelines and procedures are intended to provide maximum sample study opportunity, to preserve samples for future study, and to ensure longrange continuing service to the principle investigator and to the geoscience community.

5

Ice core drilling at Vostok  

NSF Publications Database

Jane Dionne cc: Chairperson, NSF Committee on Environmental Matters Dr. Eric Saltzman Dr. Jean Jouzel Dr. A.I. Danilov DEEP ICE CORE DRILLING AT VOSTOK STATION, ANTARCTICA: ENVIRONMENTAL ASSESSMENT Summary Statement The deep drilling project at Vostok station Antarctica involves the use of a mixture of kerosene and Freon (CFC-11) as a drilling fluid. During each drill run approximately 30 liters of drill fluid is removed from the hole on the cable, drill, and ice core.

6

Suspension Core Drill - Project DRACO,  

National Technical Information Service (NTIS)

A diamond core drill suspended by a single hose and powered by a water turbine has been developed and tested. For deep hole use, quick access and withdrawal are achieved as drill pipe is not used. 1-1/4-inch cores have been taken from blocks of Barre gran...

J. A. Browning

1985-01-01

7

Comparison of hydrogeochemical logging of drilling fluid during coring with the results from geophysical logging and hydraulic testing Example of the Morte-Mérie scientific borehole, Ardèche-France, Deep Geology of France Programme  

NASA Astrophysics Data System (ADS)

A 980-m-deep well was cored on the Ardèche border of the Southeastern basin of France as part of the Deep Geology of France (GPF) programme. Hydrogeochemical logging was carried out during drilling, which involved the monitoring of physico-chemical parameters (pH, Eh, temperature and conductivity), and chemical parameters (concentrations of He, Rn, CO 2, CH 4, O 2 Ca, Cl and SiO 2) of the drilling fluid permanently circulating in the well. This logging programme was complemented by geophysical logging and two hydraulic tests. The combination of these measurements enabled identification of a transmissive interval due to fractures in the Jurassic carbonates, and of fluid inflow both at the base of the porous and slightly permeable Triassic sandstones and from an open fracture in the Permian conglomerates. These intervals are marked by changes in the drilling-fluid chemistry, such as an increase in chemical species content, or a drop in pH. The degree of modification depends on the natural permeability of the fractures and the salinity of the fluids. The porous and permeable intervals are also marked by He anomalies, which act as a tracer for these zones. Comparison between the geophysical and hydrogeochemical logs reveals that the latter provide information on the liquid phase, whether the fractures are productive or not, whereas the geophysical logs are more directly related to the solid phase.

Aquilina, L.; Eberschweiler, C.; Perrin, J.; Deep Geology of France Team

1996-11-01

8

Downhole geophysical data from recent deep drilling in the center of the Thuringian Basin, Germany  

NASA Astrophysics Data System (ADS)

In the framework of the INFLUINS (Integrated Fluid Dynamics in Sedimentary Basins) project, a 1.179 meter deep scientific borehole was drilled in summer 2013. The drill site is situated in the north of Erfurt, in the center of the Thuringian Basin on the crossing point of two seismic reflection profiles, which were acquired in 2011. An almost complete sequence from Keuper to the base of the Buntsandstein was drilled. Drilling, geophysical measurements and well construction were conducted for three depth intervals. First, drilling was undertaken to a depth of 313 m down to the top of the Middle Muschelkalk. Then, the Middle and Upper Muschelkalk were drilled to a depth of 515 m and the third part of the drilling campaign was finished at a depth of 1.179 m at the base of the Lower Buntsandstein. Coring was done in the depth intervals of 285 m to 420 m and 520 m to 914 m. With the help of the borehole geophysical measurements, which were done along the entire depth, stratigraphic information obtained through core samples can be extrapolated from cored sections into those depth sections, where no coring was done. Immediately after finishing drilling through a certain depth interval, borehole geophysical measurements were conducted in the open hole. Using the caliper and inclination instruments, the geometry of the well was determined. In addition, milieu, gamma-ray, spectral gamma-ray, acoustic borehole television, sonic, susceptibility, dipmeter, gamma-gamma, neutron-neutron and the dual latero-log were measured to get information about rock properties. Within rock-salt bearing depth intervals, embedded cm-thin layers of clay can be geophysically resolved. This will e.g. enable to determine and contrast the physical properties of these alternating sequences with high accuracy. Besides the in-situ well measurements rock-physical parameters of the core samples were acquired with a Multi-Sensor Core Logger (MSCL). Here, we present the new data set and discuss some preliminary results. Unexpectedly and contrary to them being prominent aquifers, like at the edges of the Thuringian Basin, the Middle Muschelkalk and Middle Buntsandstein sequences are characterized by very low porosities and no macroscopically recognizable fluid transport here.

Methe, Pascal; Goepel, Andreas; Kukowski, Nina

2014-05-01

9

Test plan for core drilling ignitability testing  

SciTech Connect

The objective of this testing is to determine if ignition occurs while core drilling in a flammable gas environment. Drilling parameters are chosen so as to provide bounding conditions for the core sampling environment. If ignition does not occur under the conditions set forth in this test, then a satisfactory level of confidence will be obtained which would allow field operations under the normal drilling conditions.

Witwer, K.S.

1996-01-01

10

A New Paradigm for Ice Core Drilling  

NASA Astrophysics Data System (ADS)

The search for answers to questions about the changing climate has created an urgent need to discover past climate signatures archived in glaciers and ice sheets, and to understand current ice sheet behavior. Recognizing that U.S. scientific productivity in this area depends upon a mechanism for ensuring continuity and international cooperation in ice coring and drilling efforts, along with the availability of appropriate drills, drilling expertise, and innovations in drilling technology, the U.S. National Science Foundation (NSF) has established the Ice Drilling Program Office (IDPO) and its partner, the Ice Drilling Design and Operations group (IDDO), together known as IDPO/IDDO (Figure 1). This approach to integrated research and technology planning and delivery replaces the prior approach to drilling, which involved a series of NSF contracts with the Polar Ice Coring Office (PICO) and Ice Coring and Drilling Services (ICDS). This contracting approach lacked integrated planning. Previously, NSF had no way to forecast what science the community would propose—it would get compelling climate proposals that needed ice cores for data, but in many cases no existing drill could retrieve the core needed in the proposal. Constructing the needed drill—a process that takes years—forced science objectives to be put on hold. Now the science community is able to give feedback on its needs to IDPO/IDDO continually, allowing those who develop drilling technology to begin designing and constructing drills that scientists will need for the science proposals that they will submit years in the future. As such, IDPO/IDDO represents a new paradigm for integrated science and science support.

Albert, Mary; Bentley, Charles; Twickler, Mark

2010-09-01

11

Geothermal temperature gradient core drill, Santiam Pass  

SciTech Connect

DOE is proposing to share in the cost of drilling a 3000-ft core hole to evaluate temperature gradients, subsurface geology and the geothermal potential of an area in the Cascade Mountains. The proposed core hole will be located in the Deschutes National Forest in Oregon, near Santiam Pass. The proposed action has been described in the Environmental Assessment (EA) for Geothermal Temperature Gradient Core Drill Santiam Pass Area (No. OR-050-9-51) prepared by the US Bureau of Land Management (BLM). DOE has determined that the BLM EA adequately addresses the impacts of the proposal and is hereby adopting the EA in partial fulfillment of its NEPA responsibilities. Based upon a review of the EA and an independent analysis, DOE has concluded that the proposed corehole drilling project does not constitute a major federal action significantly affecting the quality of the human environment within the meaning of NEPA. Therefore, an environmental impact statement will not be prepared.

Not Available

1989-01-01

12

A new hybrid pressure-coring system for the drilling vessel Chikyu  

NASA Astrophysics Data System (ADS)

Retrieving core samples without releasing the in situ hydrostatic pressure during core recovery is one of the many technical challenges in scientific drilling. We report here a newly developed hybrid pressure-coring system for the use on the drilling vessel Chikyu and its successful use during expeditions 906 and 802 in the Nankai Trough of Japan. The system is gas-tight and hence enables researchers to study in situ geophysical and geochemical characteristics of sediments containing gaseous components, such as methane hydrates that cannot be reliably recovered with nonpressure coring systems. In addition, pressure coring is a powerful tool, not only for scientific but also for hydrocarbon resources research.

Kubo, Y.; Mizuguchi, Y.; Inagaki, F.; Yamamoto, K.

2014-04-01

13

Test report for core drilling ignitability testing  

SciTech Connect

Testing was carried out with the cooperation of Westinghouse Hanford Company and the United States Bureau of Mines at the Pittsburgh Research Center in Pennsylvania under the Memorandum of Agreement 14- 09-0050-3666. Several core drilling equipment items, specifically those which can come in contact with flammable gasses while drilling into some waste tanks, were tested under conditions similar to actual field sampling conditions. Rotary drilling against steel and rock as well as drop testing of several different pieces of equipment in a flammable gas environment were the specific items addressed. The test items completed either caused no ignition of the gas mixture, or, after having hardware changes or drilling parameters modified, produced no ignition in repeat testing.

Witwer, K.S.

1996-08-08

14

Barberton drilling project - Buck Reef Chert core BARB3  

NASA Astrophysics Data System (ADS)

As part of the ICDP-sponsored Barberton drilling project a single drill core (BARB3) with a total length of 899 m was obtained from the c. 3.4 Ga old Buck Reef Chert (BRC). The BRC is an unusually thick (up to 350 m) sequence of predominantly black-and-white banded chert and banded ferruginous chert that are steeply dipping. It overlies a shallow intrusive to extrusive sequence of dacitic volcanic rocks of the Hooggenoeg Formation and is separated from ultramafic lapillistone of the Kromberg Formation by a >150 m thick ultramafic sill. Drilling commenced in the ultramafic sill at an angle of c. 45° and c. 200 m of serpentinized peridotite were intersected. The remaining c. 700 m of the core include a great variety of chert lithofacies and minor intrusive mafic to intermediate igneous rocks. The base of the BRC was not intersected. Geophysical logging was done up to a depth of 847 m and included acoustic televiewer, gamma ray, resistivity, magnetic field and caliper logs. Stratigraphic and geophysical logs will be presented that will form the basis of follow-up studies on the BARB3 core. Abundance of organic matter, sulphides and Fe-bearing carbonates in specific intervals or associated with specific facies of the chert succession reflect changes in the oceanic, environmental and/or hydrothermal conditions in a shallow marine early Archaean setting. Evaluating the different processes will require a combined sedimentological, mineralogical, and geochemical approach that will provide insights into the habitat of early life, geochemical cycles and marine/hydrothermal conditions.

Hofmann, Axel; Karykowski, Bartosz; Mason, Paul; Chunnet, Gordon; Arndt, Nick

2013-04-01

15

Spectroscopic Analysis of Hydrothermal Alteration in Geothermal Drill Core  

NASA Astrophysics Data System (ADS)

Water geochemistry can vary with depth and location within a geothermal reservoir, owing to natural factors such as changing rock type, gas content, fluid source and temperature. The interaction of these variable fluids with the host rock will cause changes in the host rock and create a variety of alteration minerals and precipitates. These alteration products can suggest regions of past fluid flow in the subsurface and their mineralogy can be used to determine fluid temperature. Infrared spectroscopy is particularly good at identifying a wide variety of hydrothermal alteration minerals, requires no sample preparation, and is especially helpful in discrimination among clay minerals. We have applied traditional remote sensing hyperspectral techniques in several pilot studies of geothermal drill core and chip analysis. We have surveyed a variety of samples, including drill chip boards, boxed core, and drill cuttings from envelopes and chip trays. Alteration mineralogy can indicate both the presence of thermal fluids and the hottest fluid temperature. These preliminary studies have established reliable methods for core/chip surveys that can rapidly measure samples with high depth resolution and show the efficiency of the technique to sample continuously and provide alteration logs similar to geophysical logs. We have successfully identified a wide variety of phyllosilicates, zeolites, opal, calcite, and iron oxides and hydroxides in drill core and cuttings from geothermal wells. In high vertical resolution measurements (every 10') we note depth-associated changes in alteration minerals, patterns or zones. Temperature dependent mineral assemblages are found, both gradational with depth and as narrow zones associated with vein or fracture fill. Amorphous silica is clearly identified and seen only in the highest temperature wells. We can readily identify montmorillonite/illite transitions that may be associated with Na/Ca/K variation and may eventually be used for geothermometry. We will present an overview of these past studies, with specific comparisons to other geochemical analysis for the Humboldt House location.

Calvin, W. M.; Littlefield, E. F.

2012-12-01

16

Core Drilling For Extra-Terrestrial Mining  

NASA Astrophysics Data System (ADS)

Space Resource Utilization involves the active identification and mining of planetary bodies for commodities ranging from platinum group metals to water, such as might be realized from a dormant comet or carbonaceous chondrite like 1998 KY26, estimated to contain over 1 million gallons of water. Some proposed ET mining processes require access to sub-surface "mining zones" ranging from 10 to 200 metres and beyond. The technology used must support the identification, mining and extraction processes and must operate in milli-gravity, airless and extreme environments. This paper proposes the use of the diamond core drilling apparatus as a multi-purpose enabling technology for any extra-terrestrial sub-surface resource utilization. It specifically examines the mechanics of Diamond Drill Coring and addresses the issues required to adapt the technology to space based operations.

Boucher, D. S.; Dupuis, E.

2000-01-01

17

Creating Classroom Activities About Ocean Drilling Geophysics Through Scientist-Teacher Collaboration  

NASA Astrophysics Data System (ADS)

How can examples of geophysical data used in research be effectively taught to middle and high school students with only general science knowledge? Logging data, or logs, are continuous measurements of physical properties made in situ and at high resolution by lowering instruments into boreholes after completion of coring. As part of the Integrated Ocean Drilling Program (IODP) "School of Rock 2007" (http://www.joilearning.org/schoolofrock2007), we created a classroom activity to introduce pre-college students to representative logging data collected by the R/V JOIDES Resolution during expeditions of the Ocean Drilling Program (ODP) and the Integrated Ocean Drilling Program (IODP). The synergistic model for curriculum development involving a research scientist (Guerin) and classroom teacher (Passow) provides an efficient strategy to disseminate technical research methods and results more widely with students and teachers. The "School of Rock 2007" brought 18 educators and 12 scientists together at the Texas A and M IODP Gulf Coast Observatory for a week in July to learn about techniques in sea floor exploration and advances in understanding the Earth's climate using geophysics, biostratigraphy, geomagnetics, and more. Teachers and researchers then collaborated to produce classroom activities that will add to the existing collection of educational resources available through JOI Learning (http://www.joiscience.org/learning). The activity we developed introduces students to general concepts of downhole logging, then presents sample data from three sites. Using guiding information provided, students engage in simplified interpretation of the data to identify such features as sedimentary layers, igneous rocks, or gas hydrate-bearing formations. Activities include questions about geography, identifying patterns within the data, recognizing distinctive features in gamma ray, resistivity, density and porosity logs. The curriculum materials will be tested with students and teachers in various setting during Fall 2007, including as part of the Earth2Class Workshops for Teachers (http://www.earth2class.org) and the Lamont-Doherty Earth Observatory Open House (http://www.ldeo.columbia.edu.)

Passow, M. J.; Guerin, G.

2007-12-01

18

Concepts and Benefits of Lunar Core Drilling  

NASA Technical Reports Server (NTRS)

Understanding lunar material at depth is critical to nearly every aspect of NASA s Vision and Strategic Plan. As we consider sending human s back to the Moon for brief and extended periods, we will need to utilize lunar materials in construction, for resource extraction, and for radiation shielding and protection. In each case, we will be working with materials at some depth beneath the surface. Understanding the properties of that material is critical, thus the need for Lunar core drilling capability. Of course, the science benefit from returning core samples and operating down-hole autonomous experiments is a key element of Lunar missions as defined by NASA s Exploration Systems Architecture Study. Lunar missions will be targeted to answer specific questions concerning lunar science and re-sources.

McNamara, K. M.; Bogard, D. D.; Derkowski, B. J.; George, J. A.; Askew, R. S.; Lindsay, J. F.

2007-01-01

19

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

20

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

Microsoft Academic Search

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

D. C. Muller; J. E. Kibler

1983-01-01

21

Drilled core holes key to coalbed methane project  

SciTech Connect

An efficient system of drilling core holes for data followed by drilling, fracing, and producing gas wells helped develop economic quantities of coalbed methane. The objective of the Drunkards Wash, Utah, project is to explore for and produce commercial quantities of methane from medium-depth coal seams in east central Utah. Current gas production rates are exceeding the projections made prior to development and used for initial economic feasibility. The paper describes the coring program, drilling operations, completion practices, and production operations.

Willis, C. (River Gas Corp., Northport, AL (United States))

1995-03-06

22

Investigation of Core Drilling in Perennially Frozen Gravels and Rock.  

National Technical Information Service (NTIS)

The problems of obtaining frozen samples by core drilling of perennially frozen gravel and rock were investigated. Most of the core drilling was carried out in ice-bonded, well-graded alluvial gravel with the ground temperature near its freezing point. Bo...

G. R. Lange

1973-01-01

23

Data from core analyses, aquifer testing, and geophysical logging of Denver Basin bedrock aquifers at Castle Pines, Colorado  

USGS Publications Warehouse

This report contains data pertaining to the geologic and hydrologic characteristics of the bedrock aquifers of the Denver basin at a site near Castle Pines, Colorado. Data consist of a lithologic- description of about 2,400 ft of drill core and laboratory determinations of mineralogy, grain size, bulk and grain density, porosity, specific yield, and specific retention for selected core samples. Water-level data, atmospheric-pressure measurements, aquifer-compression measurements, and borehole geophysical logs also are included.

Robson, S. G.; Banta, E. R.

1993-01-01

24

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

25

Recent Developments and Adaptations in Diamond Wireline Core Drilling Technology  

NASA Astrophysics Data System (ADS)

Scientific drilling using diamond wireline technology is presently undergoing a significant expansion and extension of activities that has allowed us to recover geologic samples that have heretofore been technically or financially unattainable. Under the direction and management of DOSECC, a high-capacity hybrid core drilling system was designed and fabricated for the Hawaii Scientific Drilling Project (HSDP) in 1998. This system, the DOSECC Hybrid Coring System (DHCS), has the capacity to recover H-sized core from depths of more than 6 km. In 1999, the DHCS completed the first phase of the HSDP to a depth of 3100 m at a substantially lower cost per foot than any previous scientific borehole to comparable depths and, in the process, established a new depth record for recovery of H-sized wireline core. This system has been offered for use in the Unzen Scientific Drilling Project, the Chicxulub (impact crater) Scientific Drilling Project, and the Geysers Deep Geothermal Reservoir Project. More recently, DOSECC has developed a smaller barge-mounted wireline core drilling system, the GLAD800, that is capable of recovering P-sized sediment core to depths of up to 800 m. The GLAD800 has been successfully deployed on Great Salt Lake and Bear Lake in Utah and is presently being mobilized to Lake Titicaca in South America for an extensive core recovery effort there. The coring capabilities of the GLAD800 system will be available to the global lakes drilling community for acquisition of sediment cores from many of the world's deep lakes for use in calibrating and refining global climate models. Presently under development by DOSECC is a heave-compensation system that will allow us to expand the capabilities of the moderate depth coring system to allow us to collect sediment and bottom core from the shallow marine environment. The design and capabilities of these coring systems will be presented along with a discussion of their potential applications for addressing a range of earth sciences questions.

Thomas, D. M.; Nielson, D. L.; Howell, B. B.; Pardey, M.

2001-05-01

26

Long-Term Effects of Core Decompression by Drilling  

Microsoft Academic Search

Avascular necrosis of the femoral head is associated with bone marrow hyperpression. Although core decompression by drilling is an accepted treatment regimen, until today no experimental results exist concerning the physiological effects of this procedure. Published clinical data are controversial. In an animal study marrow decompression was carried out by drilling of both hips in 18 healthy male sheep. In

H.-G. Simank; J. Graf; A. Kerber; S. Wiedmaier

1997-01-01

27

Ice core drilling at McMurdo Dome  

NSF Publications Database

Title : Ice core drilling at McMurdo Dome Type : Antarctic EAM NSF Org: OD / OPP Date : July 28, 1993 File : opp93111 NATIONAL SCIENCE FOUNDATION OFFICE OF POLAR PROGRAMS OFFICE OF THE ENVIRONMENT 202/357-7766 MEMORANDUM Date: July 28, 1993 From: Acting Environmental Officer Subject: Initial Environmental Evaluation (Ice Core Drilling at McMurdo Dome, Antarctica Environmental Impact Assessment and Finding) To: Office Director, Polar Programs Manager, Polar Operations Health and Safety Officer...

28

Ultrasonic/Sonic Mechanisms for Drilling and Coring  

NASA Technical Reports Server (NTRS)

Two apparatuses now under development are intended to perform a variety of deep-drilling, coring, and sensing functions for subsurface exploration of rock and soil. These are modified versions of the apparatuses described in Ultrasonic/Sonic Drill/Corers With Integrated Sensors (NPO-20856), NASA Tech Briefs, Vol. 25, No. 1 (January 2001), page 38. In comparison with the drilling equipment traditionally used in such exploration, these apparatuses weigh less and consume less power. Moreover, unlike traditional drills and corers, these apparatuses function without need for large externally applied axial forces.

Bar-Cohen, Yoseph; Sherrit, Stewart; Dolgin, Benjamin; Askin, Steve; Peterson, Thomas M.; Bell, Bill; Kroh, Jason; Pal, Dharmendra; Krahe, Ron; Du, Shu

2003-01-01

29

Drilling the Thuringian Syncline, Germany: core processing during the INFLUINS scientific deep drilling campaign  

NASA Astrophysics Data System (ADS)

Deep drilling of the central Thuringian Syncline was carried out in order to gather substantial knowledge of subsurface fluid dynamics and fluid rock interaction within a sedimentary basin. The final depth of the borehole was successfully reached at 1179 m, just a few meters above the Buntsandstein - Zechstein boundary. One of the aspects of the scientific drilling was obtaining sample material from different stratigraphic units for insights in genesis, rock properties and fluid-rock interactions. Parts of the section were cored whereas cuttings provide record of the remaining units. Coring was conducted in aquifers and their surrounding aquitards, i.e. parts of the Upper Muschelkalk (Trochitenkalk), the Middle Muschelkalk, the Upper Buntsandstein (Pelitrot and Salinarrot) and the Middle Buntsandstein. In advance and in cooperation with the GFZ Potsdam team "Scientific Drilling" core handling was discussed and a workflow was developed to ensure efficient and appropriate processing of the valuable core material and related data. Core curation including cleaning, fitting, marking, measuring, cutting, boxing, photographing and unrolled scanning using a DMT core scanner was carried out on the drilling site in Erfurt. Due care was exercised on samples for microbiological analyses. These delicate samples were immediately cut when leaving the core tube and stored within a cooling box at -78°C. Special software for data input was used developed by smartcube GmbH. Advantages of this drilling information system (DIS) are the compatibility with formats of international drilling projects from the IODP and ICDP drilling programs and thus options for exchanges with the international data bases. In a following step, the drill cores were brought to the national core repository of the BGR in Berlin Spandau where the cores were logged for their physical rock properties using a GeoTek multi sensor core logger (MSCL). After splitting the cores into a working and archive half, the cores were scanned for compositional variations using an XRF core scanner at the BGR lab and scan images of the slabbed surfaces were performed. The average core recovery rate was very high at nearly 100%. Altogether, we gained 533 m of excellent core material including sandstones, siltstones and claystones, carbonates, sulfates and chlorides. This provides valuable insight into the stratigraphic column of the Thuringian Syncline.

Abratis, Michael; Methe, Pascal; Aehnelt, Michaela; Kunkel, Cindy; Beyer, Daniel; Kukowski, Nina; Totsche, Kai Uwe

2014-05-01

30

Stress orientations of Taiwan Chelungpu-Fault Drilling Project (TCDP) hole-A as observed from geophysical logs  

USGS Publications Warehouse

The Taiwan Chelungpu-fault Drilling Project (TCDP) drilled a 2-km-deep research borehole to investigate the structure and mechanics of the Chelungpu Fault that ruptured in the 1999 Mw 7.6 Chi-Chi earthquake. Geophysical logs of the TCDP were carried out over depths of 500-1900 in, including Dipole Sonic Imager (DSI) logs and Formation Micro Imager (FMI) logs in order to identify bedding planes, fractures and shear zones. From the continuous core obtained from the borehole, a shear zone at a depth of 1110 meters is interpreted to be the Chelungpu fault, located within the Chinshui Shale, which extends from 1013 to 1300 meters depth. Stress-induced borehole breakouts were observed over nearly the entire length of the wellbore. These data show an overall stress direction (???N115??E) that is essentially parallel to the regional stress field and parallel to the convergence direction of the Philippine Sea plate with respect to the Eurasian plate. Variability in the average stress direction is seen at various depths. In particular there is a major stress orientation anomaly in the vicinity of the Chelungpu fault. Abrupt stress rotations at depths of 1000 in and 1310 in are close to the Chinshui Shale's upper and lower boundaries, suggesting the possibility that bedding plane slip occurred during the Chi-Chi earthquake. Copyright 2007 by the American Geophysical Union.

Wu, H. -Y.; Ma, K. -F.; Zoback, M.; Boness, N.; Ito, H.; Hung, J. -H.; Hickman, S.

2007-01-01

31

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

National Technical Information Service (NTIS)

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

R. E. Hodges, W. E. Teasdale

1991-01-01

32

Selected data fron continental scientific drilling core holes VC-1 and VC-2a, Valles Caldera, New Mexico  

SciTech Connect

This report presents geochemical and isotopic data on rocks and water and wellbore geophysical data from the Continental Scientific Drilling Program core holes VC-1 and VC-2a, Valles Caldera, New Mexico. These core holes were drilled as a portion of a broader program that seeks to answer fundamental questions about magma, water/rock interactions, ore deposits, and volcanology. The data in this report will assist the interpretation of the hydrothermal system in the Jemez Mountains and will stimulate further research in magmatic processes, hydrothermal alteration, ore deposits, hydrology, structural geology, and hydrothermal solution chemistry. 37 refs., 36 figs., 28 tabs.

Musgrave, J.A.; Goff, F.; Shevenell, L.; Trujillo, P.E. Jr.; Counce, D.; Luedemann, G.; Garcia, S.; Dennis, B.; Hulen, J.B.; Janik, C.; Tomei, F.A.

1989-02-01

33

Preliminary report on the geology and geophysics of drill hole UE25a-1, Yucca Mountain, Nevada Test Site  

USGS Publications Warehouse

A subsurface geologic study in connection with the Nevada Nuclear Waste Storage Investigations has furnished detailed stratigraphic and structural information about tuffs underlying northeastern Yucca Mountain on the Nevada Test Site. Drill hole UE25a-1 penetrated thick sequences of nonwelded to densely welded ash-flow and bedded tuffs of Tertiary age. Stratigraphic units that were identified from the drill-hole data include the Tiva Canyon and Topopah Spring Members of the Paintbrush Tuff, tuffaceous beds of Calico Hills, and the Prow Pass and Bullfrog Members of the Crater Flat Tuff. Structural analysis of the core indicated densely welded zones to be highly fractured. Many fractures show near-vertical inclinations and are commonly coated with secondary silica, manganese and iron oxides, and calcite. Five fault zones were recognized, most of which occurred in the Topopah Spring Member. Shear fractures commonly show oblique-slip movement and some suggest a sizable component of lateral compression. Graphic logs are included that show the correlation of lithology, structural properties, and geophysical logs. Many rock units have characteristic log responses but highly fractured zones, occurring principally in the Tiva Canyon and Topopah Spring Members, restricted log coverage to the lower half of the drill hole.

Spengler, Richard W.; Muller, D. C.; Livermore, R. B.

1979-01-01

34

Stratigraphy of the Apollo 15 drill core  

NASA Technical Reports Server (NTRS)

The crew of Apollo 15 collected at 242-centimeter-long core of the regolith of the moon developed on the surface of Palus Putredinis 3 deg 39 min 20 sec E, 26 deg 26 min 00 sec N. The 2.04-centimeter-diameter core, which has a mass of 1333.2 grams, consists of 42 major textural units, with thicknesses ranging from a few milliliters to 13 centimeters thick. The regolith is not homogeneous and is composed of many layers that are mostly ejecta from impact events.

Heiken, G.; Duke, M.; Fryxell, R.; Nagle, J. S.; Scott, R.; Sellers, G. A.

1972-01-01

35

Application of scientific core drilling to geothermal exploration: Platanares, Honduras and Tecuamburro Volcano, Guatemala, Central America  

SciTech Connect

Our efforts in Honduras and Guatemala were part of the Central America Energy Resource Project (CAERP) funded by the United States Agency for International Development (AID). Exploration core drilling operations at the Platanares, Honduras and Tecuamburro Volcano, Guatemala sites were part of a geothermal assessment for the national utility companies of these countries to locate and evaluate their geothermal resources for electrical power generation. In Honduras, country-wide assessment of all thermal areas determined that Platanares was the site with the greatest geothermal potential. In late 1986 to middle 1987, three slim core holes were drilled at Platanares to a maximum depth of 680 m and a maximum temperature of 165{degree}C. The objectives were to obtain information on the geothermal gradient, hydrothermal alterations, fracturing, and possible inflows of hydrothermal fluids. Two holes produced copious amounts of water under artesian conditions and a total of 8 MW(t) of energy. Geothermal investigations in Guatemala focused on the Tecuamburro Volcano geothermal site. The results of surface geological, volcanological, hydrogeochemical, and geophysical studies at Tecuamburro Volcano indicated a substantial shallow heat source. In early 1990 we drilled one core hole, TCB-1, to 808 m depth. The measured bottom hole temperature was 238{degree}C. Although the borehole did not flow, in-situ samples indicate the hole is completed in a vapor-zone above a probable 300{degree}C geothermal reservoir.

Goff, S.J.; Goff, F.E.; Heiken, G.H. [Los Alamos National Lab., NM (United States); Duffield, W.A. [Geological Survey, Flagstaff, AZ (United States); Janik, C.J. [Geological Survey, Menlo Park, CA (United States)

1994-04-01

36

Drilling report and core logs for the 1981 drilling of Kilauea Iki lava lake, Kilauea volcano, Hawaii, with comparative notes on earlier (1967-1979) drilling experiences  

SciTech Connect

The purpose is: (1) to describe the 1981 drilling of Kilauea Iki lava lake, (2) to present the logs for the drill core recovered during the 1981 drilling, and (3) to present a summary of some of the field observations made during the 1967, 1975, 1976 and 1979 drillings that are relevant to the crystallization history of Kilauea Iki lava lake. This report supplements logs for the 1967-1979 core presented in Helz et al. (1980). 21 references, 4 figures, 4 tables.

Helz, R.T.; Wright, T.L.

1983-01-01

37

REVIEW ARTICLE: Geophysical signatures of oceanic core complexes  

NASA Astrophysics Data System (ADS)

Oceanic core complexes (OCCs) provide access to intrusive and ultramafic sections of young lithosphere and their structure and evolution contain clues about how the balance between magmatism and faulting controls the style of rifting that may dominate in a portion of a spreading centre for Myr timescales. Initial models of the development of OCCs depended strongly on insights available from continental core complexes and from seafloor mapping. While these frameworks have been useful in guiding a broader scope of studies and determining the extent of OCC formation along slow spreading ridges, as we summarize herein, results from the past decade highlight the need to reassess the hypothesis that reduced magma supply is a driver of long-lived detachment faulting. The aim of this paper is to review the available geophysical constraints on OCC structure and to look at what aspects of current models are constrained or required by the data. We consider sonar data (morphology and backscatter), gravity, magnetics, borehole geophysics and seismic reflection. Additional emphasis is placed on seismic velocity results (refraction) since this is where deviations from normal crustal accretion should be most readily quantified. However, as with gravity and magnetic studies at OCCs, ambiguities are inherent in seismic interpretation, including within some processing/analysis steps. We briefly discuss some of these issues for each data type. Progress in understanding the shallow structure of OCCs (within ~1 km of the seafloor) is considerable. Firm constraints on deeper structure, particularly characterization of the transition from dominantly mafic rock (and/or altered ultramafic rock) to dominantly fresh mantle peridotite, are not currently in hand. There is limited information on the structure and composition of the conjugate lithosphere accreted to the opposite plate while an OCC forms, commonly on the inside corner of a ridge-offset intersection. These gaps preclude full testing of current models. However, with the data in hand there are systematic patterns in OCC structure, such as the 1-2 Myr duration of this rifting style within a given ridge segment, the height of the domal cores with respect to surrounding seafloor, the correspondence of gravity highs with OCCs, and the persistence of corrugations that mark relative (palaeo) slip along the exposed detachment capping the domal cores. This compilation of geophysical results at OCCs should be useful to investigators new to the topic but we also target advanced researchers in our presentation and synthesis of findings to date.

Blackman, Donna K.; Canales, J. Pablo; Harding, Alistair

2009-08-01

38

Depositional history of the Apollo 16 deep drill core  

NASA Technical Reports Server (NTRS)

Ferromagnetic resonance and magnetic hysteresis loop measurements were performed on 212 samples from the Apollo 16 deep drill core. The total iron content is generally uniform with a mean value of 5.7 plus or minus 0.9 wt%. The soils range in maturity from immature to mature. Two major contacts were observed. The contact at 13 cm depth represents a fossil surface whereas the contact at 190 cm depth has no time-stratigraphic significance. The data suggest that the core section below 13 cm depth was deposited in a single impact event and subjected to meteoritic gardening for about 450 m.y. However, our data do not preclude deposition by a series of closely spaced events. About 50 m.y. ago, the top 13 cm were added. Comparison with the Apollo 16 double drive tube 60009/60010 does not yield any evidence for a stratigraphic correlation with the deep drill core.

Gose, W. A.; Morris, R. V.

1977-01-01

39

Managing Geothermal Exploratory Drilling Risks Drilling Geothermal Exploration and Delineation Wells with Small-Footprint Highly Portable Diamond Core Drills  

NASA Astrophysics Data System (ADS)

Small hydraulic core rigs are highly portable (truck or scow-mounted), and have recently been used for geothermal exploration in areas such as Nevada, California, the Caribbean Islands, Central and South America and elsewhere. Drilling with slim diameter core rod below 7,000' is common, with continuous core recovery providing native-state geological information to aid in identifying the resource characteristics and boundaries; this is a highly cost-effective process. Benefits associated with this innovative exploration and delineation technology includes the following: Low initial Capital Equipment Cost and consumables costs Small Footprint, reducing location and road construction, and cleanup costs Supporting drill rod (10'/3meter) and tools are relatively low weight and easily shipped Speed of Mobilization and rig up Reduced requirements for support equipment (cranes, backhoes, personnel, etc) Small mud systems and cementing requirements Continuous, simplified coring capability Depth ratings comparable to that of large rotary rigs (up to ~10,000'+) Remote/small-location accessible (flown into remote areas or shipped in overseas containers) Can be scow or truck-mounted This technical presentation's primary goal is to share the technology of utilizing small, highly portable hydraulic coring rigs to provide exploratory drilling (and in some cases, production drilling) for geothermal projects. Significant cost and operational benefits are possible for the Geothermal Operator, especially for those who are pursuing projects in remote locations or countries, or in areas that are either inaccessible or in which a small footprint is required. John D. Tuttle Sinclair Well Products jtuttle@sinclairwp.com

Tuttle, J.; Listi, R.; Combs, J.; Welch, V.; Reilly, S.

2012-12-01

40

Drilling cores on the sea floor with the remote-controlled sea floor drilling rig MeBo  

NASA Astrophysics Data System (ADS)

The sea floor drill rig MeBo (acronym for Meeresboden-Bohrgerät, German for sea floor drill rig) is a robotic drill rig that is deployed on the sea floor and operated remotely from the research vessel to drill up to 80 m into the sea floor. It was developed at the MARUM Research Center for Marine Environmental Sciences at Bremen University. The complete system - comprising the drill rig, winch, control station, and the launch and recovery system - is transported in six containers and can be deployed worldwide from German and international research ships. It was the first remote-controlled deep sea drill rig to use a wireline coring technique. Compared to drilling vessels this technology has the advantage of operating from a stable platform at the sea bed, which allows for optimal control over the drilling process. Especially for shallow drillings in the range of tens to hundreds of metres, sea bed drill rigs are time-efficient since no drill string has to be assembled from the ship to the sea floor before the first core can be taken. The MeBo has been successfully operated, retrieving high-quality cores at the sea bed for a variety of research fields, including slope stability studies and palaeoclimate reconstructions. Based on experience with the MeBo, a rig is now being built that will be able to drill to a depth of 200 m.

Freudenthal, T.; Wefer, G.

2013-12-01

41

The Chicxulub Multiring Impact Crater and the Cretaceous/Paleogene Boundary: Results From Geophysical Surveys and Drilling  

NASA Astrophysics Data System (ADS)

The Chicxulub crater has attracted considerable attention as one of the three largest terrestrial impact structures and its association with the Cretaceous/Paleogene boundary (K/Pg). Chicxulub is a 200 km-diameter multi-ring structure formed 65.5 Ma ago in the Yucatan carbonate platform in the southern Gulf of Mexico and which has since been buried by Paleogene and Neogene carbonates. Chicxulub is one of few large craters with preserved ejecta deposits, which include the world-wide K/Pg boundary clay layer. The impact has been related to the global major environmental and climatic effects and the organism mass extinction that mark the K/Pg boundary, which affected more than 70 % of organisms, including the dinosaurs, marine and flying reptiles, ammonites and a large part of the marine microorganisms. The impact and crater formation occur instantaneously, with excavation of the crust down to 25 km depths in fractions of second and lower crust uplift and crater formation in a few hundreds of seconds. Energy released by impact and crustal deformation generates seismic waves traveling the whole Earth, and resulting in intense fracturing and deformation at the target site. Understanding of the physics of impacts on planetary surfaces and modeling of processes of crustal deformation, rheological behavior of materials at high temperatures and pressures remain a major challenge in geosciences. Study of the Chicxulub crater and the global effects and mass extinction requires inter- and multidisciplinary approaches, with researchers from many diverse fields beyond the geosciences. With no surface exposures, geophysical surveys and drilling are required to study the crater. Differential compaction between the impact breccias and the surrounding carbonate rocks has produced a ring-fracture structure that at the surface reflects in a small topographic depression and the karstic cenote ring. The crater structure, located half offshore and half on-land, has been imaged by different geophysical aerial, land and marine methods including gravity, magnetics, electromagnetics and seismic refraction and reflection. The impact lithologies and carbonate sequence have been cored as part of several drilling projects. Here we analyze the stratigraphy of Chicxulub from borehole logging data and core analyses, with particular reference to studies on CSDP Yaxcopoil-1 and UNAM Santa Elena boreholes. Analyses of core samples have examined the stratigraphy of the cover carbonate sequence, impact breccia contact and implications for impact age, K/Pg global correlations and paleoenvironmental conditions following impact. The K/Pg age for Chicxulub has been supported from different studies, including Ar/Ar dating, magnetic polarity stratigraphy, geochemistry and biostratigraphy. A Late Maastrichtian age has also been proposed for Chicxulub from studies in Yaxcopoil-1 basal Paleocene carbonates, with impact occurring 300 ka earlier predating the K/Pg boundary. This proposal calls attention to the temporal resolution of stratigraphic and chronological methods, and the need for further detailed analyses of the basal carbonate sections in existing boreholes and new drilling/coring projects. Stratigraphy of impact ejecta and basal sediments in Yaxcopoil-1 and UNAM boreholes indicates a hiatus in the basal sequence. Modeling of post- impact processes suggest erosion effects due to seawater back surge, block slumping and partial rim collapse of post-impact crater modification. Analyses of stable isotopes and magnetostratigraphic data for the Paleocene carbonate sequences in Yaxcopoil-1 and Santa Elena boreholes permit to investigate the post- impact processes, depositional conditions and age of basal sediments. Correlation of stable isotopes with the global pattern for marine carbonate sediments provides a stratigraphic framework for the basal Paleocene carbonates. The analyses confirm a K/Pg boundary age for the Chicxulub impact. References: Collins et al, 2008. Earth Planetary Science Letters 270, 221-230; Gulick et al, 2008. Nature Geoscience 1, 131-135; Hild

Urrutia-Fucugauchi, J.; Perez-Cruz, Ligia

2010-03-01

42

Conduit drilling at Unzen volcano, Japan: core description and interpretation  

NASA Astrophysics Data System (ADS)

A 1996-m-long hole has been drilled on a slanted trajectory that passed beneath Unzen volcano, Japan. The hole penetrated central conduit region of the volcano at ~1600 m below the summit. Drill cores at 50 m intervals were recovered from the hole. The principal facies of the drill cores in the conduit region are polymictic breccia and coherent dacite. The polymictic breccia is non-stratified, poorly sorted and made up of heterolithologic, polyhedral dacite clasts 10-50 mm across, which are embedded in a cogenetic matrix. Larger clasts up to 50 cm across rarely occur. The clasts consist of non-vesicular, porphyritic dacite, which varies in color (greenish grey to grey), alteration, phenocryst size and phenocryst proportion. They show clast-rotated texture, and no jigsaw-fit texture. The edges of the clasts are commonly rounded. The matrix of the breccia is reddish grey, dense (low porosity) and composed of angular dacite fragments up to 5 mm across. The coherent dacite is grey, massive and porphyritic. It contains plagioclase and hornblende phenocrysts. The matrix of the dacite is mostly crystalline, but gradation from light grey, crystalline dacite to dark grey, glassy dacite occurs. These polymictic breccia and coherent dacite have been in places intruded by veins up to 10 mm wide. The veins vary in color (white, greenish grey and black) and components (fine-grain cray minerals, coarse rock fragments). Some veins show laminations along the vein wall. The morphological features of the polymictic breccia suggest that the breecia formed within the conduit region of the volcano in response to fragmentation of rocks due to explosions, but did not extrude from the vent and recycled within the conduit region. The coherent dacite facies is probably a dyke with chilled margins. The veins may have formed by injections of high-temperature gas and/or liquid into fractures around dykes during dyke intrusions. The descriptions of the drill core, together with composition of drill cuttings, electric conductivity of the borehole (FMS image) and seismological data during 1990-1995 eruption, suggest that the conduit region of the Unzen volcano is 300-350 m wide at ~1600 m below the summit, and consists of polymictic breccia and several, parallel, vertical dykes, intruding the breccia. Each dyke is tabular-shaped and 3-30 m thick. Thin dykes (3-8 m thick) have simple, uniformed interior and are inferred to have formed by single injection of magma. On the other hand, thick dykes (26-30 m) have several cooling units within, and probably formed by several magma injections.

Goto, Y.; Nakada, S.; Yoshimoto, M.; Shimano, T.; Kurokawa, M.; Sakuma, S.; Sugimoto, T.; Noguchi, S.; Toramaru, A.; Hoshizumi, H.; Oguri, K.; Uto, K.

2004-12-01

43

Research core drilling in the Manson impact structure, Iowa  

NASA Technical Reports Server (NTRS)

The Manson impact structure (MIS) has a diameter of 35 km and is the largest confirmed impact structure in the United States. The MIS has yielded a Ar-40/Ar-39 age of 65.7 Ma on microcline from its central peak, an age that is indistinguishable from the age of the Cretaceous-Tertiary boundary. In the summer of 1991 the Iowa Geological Survey Bureau and U.S. Geological Survey initiated a research core drilling project on the MIS. The first core was beneath 55 m of glacial drift. The core penetrated a 6-m layered sequence of shale and siltstone and 42 m of Cretaceous shale-dominated sedimentary clast breccia. Below this breccia, the core encountered two crystalline rock clast breccia units. The upper unit is 53 m thick, with a glassy matrix displaying various degrees of devitrification. The upper half of this unit is dominated by the glassy matrix, with shock-deformed mineral grains (especially quartz) the most common clast. The glassy-matrix unit grades downward into the basal unit in the core, a crystalline rock breccia with a sandy matrix, the matrix dominated by igneous and metamorphic rock fragments or disaggregated grains from those rocks. The unit is about 45 m thick, and grains display abundant shock deformation features. Preliminary interpretations suggest that the crystalline rock breccias are the transient crater floor, lifted up with the central peak. The sedimentary clast breccia probably represents a postimpact debris flow from the crater rim, and the uppermost layered unit probably represents a large block associated with the flow. The second core (M-2) was drilled near the center of the crater moat in an area where an early crater model suggested the presence of postimpact lake sediments. The core encountered 39 m of sedimentary clast breccia, similar to that in the M-1 core. Beneath the breccia, 120 m of poorly consolidated, mildly deformed, and sheared siltstone, shale, and sandstone was encountered. The basal unit in the core was another sequence of sedimentary clast breccia. The two sedimentary clast units, like the lithologically similar unit in the M-1 core, probably formed as debris flows from the crater rim. The middle, nonbrecciated interval is probably a large, intact block of Upper Cretaceous strata transported from the crater rim with the debris flow. Alternatively, the sequence may represent the elusive postimpact lake sequence.

Anderson, R. R.; Hartung, J. B.; Roddy, D. J.; Shoemaker, E. M.

1992-01-01

44

Miniature CVD-Diamond Coring Drills for Robotic Sample Collection and Analysis  

NASA Astrophysics Data System (ADS)

Chemical vapor deposition (CVD) can be used to fabricate small diamond core drills that are relatively transparent to X-rays and to infrared radiation, allowing the drill to double as a sample holder.

Vaniman, D. T.; Trava-Airoldi, V. J.; Bish, D. L.; Chipera, S. J.

2003-03-01

45

Drilling cores on the sea floor with the remote-controlled sea-floor drilling rig MeBo  

NASA Astrophysics Data System (ADS)

Sampling of the upper 50 to 200 m of the sea floor to address questions relating to marine mineral resources and gas hydrates, for geotechnical research in areas of planned offshore installations, to study slope stability, and to investigate past climate fluctuations, to name just a few examples, is becoming increasingly important both in shallow waters and in the deep sea. As a rule, the use of drilling ships for this kind of drilling is inefficient because before the first core can be taken a drill string has to be assembled extending from the ship to the sea floor. Furthermore, movement of the ship due to wave motion disturbs the drilling process and often results in poor core quality, especially in the upper layers of the sea floor. For these reasons, the MeBo drilling rig, which is lowered to the sea floor and operated remotely from the ship to drill up to 80 m into the sea floor, was developed at the MARUM Research Center for Marine Environmental Sciences at Bremen University. The complete system, comprising the drill rig, winch, control station, and the launch and recovery system, is transported in six containers and can be deployed worldwide from German and international research ships. It was the first remote-controlled deep sea drill rig that uses a wireline coring technique. Based on the experiences with the MeBo a rig is now being built that will be able to drill to a depth of 200 m.

Freudenthal, T.; Wefer, G.

2013-07-01

46

Petrophysical analysis of geophysical logs of the National Drilling Company-U.S. Geological Survey ground-water research project for Abu Dhabi Emirate, United Arab Emirates  

USGS Publications Warehouse

A program of borehole-geophysical logging was implemented to supply geologic and geohydrologic information for a regional ground-water investigation of Abu Dhabi Emirate. Analysis of geophysical logs was essential to provide information on geohydrologic properties because drill cuttings were not always adequate to define lithologic boundaries. The standard suite of logs obtained at most project test holes consisted of caliper, spontaneous potential, gamma ray, dual induction, microresistivity, compensated neutron, compensated density, and compensated sonic. Ophiolitic detritus from the nearby Oman Mountains has unusual petrophysical properties that complicated the interpretation of geophysical logs. The density of coarse ophiolitic detritus is typically greater than 3.0 grams per cubic centimeter, porosity values are large, often exceeding 45 percent, and the clay fraction included unusual clays, such as lizardite. Neither the spontaneous-potential log nor the natural gamma-ray log were useable clay indicators. Because intrinsic permeability is a function of clay content, additional research in determining clay content was critical. A research program of geophysical logging was conducted to determine the petrophysical properties of the shallow subsurface formations. The logging included spectral-gamma and thermal-decay-time logs. These logs, along with the standard geophysical logs, were correlated to mineralogy and whole-rock chemistry as determined from sidewall cores. Thus, interpretation of lithology and fluids was accomplished. Permeability and specific yield were calculated from geophysical-log data and correlated to results from an aquifer test. On the basis of results from the research logging, a method of lithologic and water-resistivity interpretation was developed for the test holes at which the standard suite of logs were obtained. In addition, a computer program was developed to assist in the analysis of log data. Geohydrologic properties were estimated, including volume of clay matrix, volume of matrix other than clay, density of matrix other than clay, density of matrix, intrinsic permeability, specific yield, and specific storage. Geophysical logs were used to (1) determine lithology, (2) correlate lithologic and permeable zones, (3) calibrate seismic reprocessing, (4) calibrate transient-electromagnetic surveys, and (5) calibrate uphole-survey interpretations. Logs were used at the drill site to (1) determine permeability zones, (2) determine dissolved-solids content, which is a function of water resistivity, and (3) design wells accordingly. Data and properties derived from logs were used to determine transmissivity and specific yield of aquifer materials.

Jorgensen, Donald G.; Petricola, Mario

1994-01-01

47

Learning Activities Developed at The University of Texas at Austin Institute for Geophysics Using Ocean Drilling Science, Technology and Data  

Microsoft Academic Search

NSF GK-12 Fellows at The University of Texas at Austin Institute for Geophysics (UTIG) actively contribute to K-12 education by linking K-12 students and teachers to research scientists and recent discoveries, and by developing hands-on learning activities designed primarily for secondary school learning environments. The excitement of the new Integrated Ocean Drilling Program (IODP), an international research program that explores

D. M. Bailey; J. Stevens; D. Clarke; K. Ellins; G. Tynes; M. Petkovsek

2004-01-01

48

Discoveries Within the Ice: Plans of the Ice Coring and Drilling Science Community  

NASA Astrophysics Data System (ADS)

The search for answers to questions about our changing climate creates an urgent need to discover the clues to the past archived in glaciers and ice sheets, and to understand current ice sheet behavior. Recognizing that U.S. scientific productivity in this area depends upon a mechanism for ensuring continuity and international cooperation in ice coring and drilling efforts, along with availability of appropriate drills, drilling expertise, and innovations in drilling technology, the Ice Drilling Program Office (IDPO) and its partner, the Ice Drilling Design and Operations group (IDDO), collectively known as IDPO/IDDO, work with the science community to articulate integrated research, technological planning and delivery. This presentation highlights science goals articulated in the IDPO Long Range Science Plan, which lays out the scientific goals and future directions of the multidisciplinary research community and international partners. The science fits into four broad categories: Climate; Ice Dynamics and History; the Sub-ice Environment; and Ice as a Scientific Observatory. A companion plan, the IDDO Long Range Drilling Technology Plan, discusses details of the drills and new development driven by the Long Range Science Plan. The ice drilling technology described in the Long Range Drilling Technology Plan spans from the use of the multi-ton Deep Ice Sheet Coring (DISC) drill for deep drilling projects such as the West Antarctic Ice Sheet Divide, in Antarctica, to shallow drilling endeavors using hand augers, and beyond to identification of new drilling tools not yet in existence.

Albert, M. R.; Bentley, C. R.; Twickler, M.; Idpo/Iddo

2010-12-01

49

Physical-Property Measurements on Core samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect, North-Central Nevada  

USGS Publications Warehouse

From May to June 2008, the U.S. Geological Survey (USGS) collected and measured physical properties on 36 core samples from drill-hole Deep Blue No. 1 (DB-1) and 46 samples from drill-hole Deep Blue No. 2 (DB-2) along the west side of Blue Mountain about 40 km west of Winnemucca, Nev. These data were collected as part of an effort to determine the geophysical setting of the Blue Mountain geothermal prospect as an aid to understanding the geologic framework of geothermal systems throughout the Great Basin. The physical properties of these rocks and other rock types in the area create a distinguishable pattern of gravity and magnetic anomalies that can be used to infer their subsurface geologic structure. Drill-holes DB-1 and DB-2 were spudded in alluvium on the western flank of Blue Mountain in 2002 and 2004, respectively, and are about 1 km apart. Drill-hole DB-1 is at a ground elevation of 1,325 m and was drilled to a depth of 672 m and drill-hole DB-2 is at a ground elevation of 1,392 m and was drilled to a depth of 1522 m. Diameter of the core samples is 6.4 cm. These drill holes penetrate Jurassic and Triassic metasedimentary rocks predominantly consisting of argillite, mudstone, and sandstone; Tertiary diorite and gabbro; and younger Tertiary felsic dikes.

Ponce, David A.; Watt, Janet T.; Casteel, John; Logsdon, Grant

2009-01-01

50

Physical parameters measured on cores and cuttings from the pilot well (0 m 4000.1 m) of the German continental deep drilling program (KTB) in the Oberfalz area, Bavaria, Federal Republic of Germany  

NASA Astrophysics Data System (ADS)

The project of an ultradeep drill hole (KTB) in the Oberpfalz area at the western margin of the Bohemian Massif has completed a pilot drill hole to a depth of 4000.1 m in April 1989. This well is situated only about 200m away from the main drill hole aimed at 10 km depth where drilling started in September 1990. The cores of the pilot well have a diameter of 9.4 cm or 10.16 cm, respectively. In addition to cores and cuttings there was also mud available for geochemical, petrological and some geophysical measurements. The pilot drill hole has a core recovery length of as much as 3042.6 m (about 76%), among which 193.1 m were obtained by rotary drilling and 2849.5 m by wireline drilling. Several petrophysical parameters were measured in a specially established field laboratory at the drill site immediately after sampling in order to obtain as good as possible in-situ values. Results for the following parameters are reported: density, natural gamma ray activity, velocities of seismic longitudinal and shear waves, thermal conductivity, electrical resistivity, natural remanent magnetization, magnetic susceptibility, porosity and inner surface. The methods of measurement are characterized briefly and the results of the pilot drill hole are presented and discussed in connection with the lithology and the geophysical anomalies, which have been observed on the surface.

Soffel, H. C.; Bücker, Ch.; Gebrande, H.; Huenges, E.; Lippman, E.; Pohl, J.; Rauen, A.; Schult, A.; Streit, K. M.; Wienand, F.

1992-01-01

51

Application of three-dimensional digital image correlation to the core-drilling method  

Microsoft Academic Search

We present a non-destructive technique for the determination ofin situ stresses in concrete structures, reterred to as the core-drilling method. The method is similar to the American Society for\\u000a Testing and Materials (ASTM) hole-drilling strain gage method, except that the core-drilling method is formulated in the current\\u000a work are performed with traditional photogrammetry, and the more novel (and more accurate)

M. J. McGinnis; S. Pessiki; H. Turker

2005-01-01

52

Agglutinates as recorders of regolith evolution - Application to the Apollo 17 drill core  

NASA Technical Reports Server (NTRS)

Chemical data are reported for agglutinates from 26 depth intervals of the Apollo 17 deep drill core, and the compositions of the agglutinates are compared with those of the soils in which they occur. The agglutinate sequence suggests a scenario in which several closely-spaced depositional events were involved in the formation of the drill core, rather than a continuous accumulation process.

Laul, J. C.; Smith, M. R.; Papike, J. J.; Simon, S. B.

1984-01-01

53

Geophysics  

NSDL National Science Digital Library

This website contains abbreviated course notes from a geophysics class at California State University at Sacramento. The notes contain topic summaries and formulas, including gravity, Newton's laws, radioactivity, radioactive decay, Rb/Sr dating, Uranium-Thorium-Lead dating, uses of Lead, fission-track dating, Potassium-Argon dating, Carbon dating, heat, magnetism, seismology and earthquake prediction.

Slaymaker, Susan

54

Tecuamburro Volcano, Guatemala geothermal gradient core hole drilling, operations, and preliminary results  

Microsoft Academic Search

A geothermal gradient core hole (TCB-1) was drilled to a depth of 700+ m at the Tecuamburro geothermal site, Guatemala during February and March, 1990. The core hole is located low on the northern flank of the Tecuamburro Volcano complex. Preliminary analysis of cores (>98% core recovery) indicates that the hydrothermal system may be centered in the 4-km-diameter Chupadero Crater,

S. Goff; G. Heiken; F. Goff; J. Gardner; W. Duffield; L. Martinelli; S. Aycinena; O. Castaneda

1990-01-01

55

Fluid flow restrictor valve for a drill hole coring tool  

SciTech Connect

An apparatus operable on a wireline logging cable for drilling a hole in the sidewall of a drill hole which comprises a hydraulically operated backup shoe for wedging the apparatus at a selected location in the drill hole, a hydraulic motor with a drilling bit connected thereto for rotation by the hydraulic motor and hydraulic means connected to the hydraulic motor for moving the bit into drilling engagement with the sidewall of the drill hole. In the improvement of this invention, the hydraulic means for moving the bit into drilling engagement comprises a new flow restrictor valve. This flow restrictor valve has an orifice and a slender pointed rod for restricting the flow of fluid through the orifice. Opposing spring means and control fluid means engage the rod for controlling its movement toward and away from the orifice.

Mount, H.B.

1981-07-28

56

Seismic-Stratigraphic Framework for Drill Cores and Paleoclimate Records in Bear Lake, Utah-Idaho  

Microsoft Academic Search

A 200-km network of high-resolution seismic-reflection profiles was collected in Bear Lake, Utah-Idaho, in order to explore the sedimentary framework of the lake's paleoclimate record as derived from cores and drill holes. In addition to a series of short cores, including piston cores as much as 5 m long, two deep holes were drilled at a site on one of

S. M. Colman

2001-01-01

57

Surface elevation change artifact at the NEEM ice core drilling site, North Greenland.  

NASA Astrophysics Data System (ADS)

The NEEM deep drilling site (77.45°N 51.06°W) is located at the main ice divide in North Greenland. For the ice core drilling project, a number of buildings was erected and left on the snow surface during the five-year project period. The structures created snowdrifts that formed accordingly to the predominant wind direction on the lee side on the buildings and the overwintering cargo. To get access to the buildings, the snowdrifts and the accumulated snow were removed and the surface in the camp was leveled with heavy machinery each summer. In the camp a GPS reference pole was placed as a part of the NEEM strain net, 12 poles placed in three diamonds at distances of 2,5 km, 7,5 km and 25 km they were all measured with high precision GPS every year. Around the reference pole, a 1 km x 1 km grid with a spacing of 100 m was measured with differential GPS each year. In this work, we present results from the GPS surface topography measurements in and around the campsite. The mapping of the topography in and around the campsite shows how the snowdrifts evolve and are the reason for the lift of the camp site area. The accumulated snowdrifts are compared to the dominant wind directions from year to year. The annual snow accumulation at the NEEM site is 0.60 m. The reference pole in the camp indicates an additional snow accumulation of 0.50 m per year caused by collected drifting snow. The surface topography mapping shows that this artificially elevated surface extends up to several kilometers out in the terrain. This could have possible implications on other glaciological and geophysical measurements in the area i.e. pit and snow accumulation studies.

Berg Larsen, Lars; Schøtt Hvidberg, Christine; Dahl-Jensen, Dorthe; Lilja Buchardt, Susanne

2014-05-01

58

Melt in the impact breccias from the Eyreville drill cores, Chesapeake Bay impact structure, USA  

Microsoft Academic Search

The center of the 35.3 Ma Chesapeake Bay impact structure (85 km diameter) was drilled during 2005\\/2006 in an ICDP-0USGS drilling project. The Eyreville drill cores include polymict impact breccias and associated rocks (1397-01551 m depth). Tens of melt particles from these impactites were studied by optical and electron microscopy, electron microprobe, and microRaman spectroscopy, and classified into six groups:

Katerina Bartosova; Lutz Hecht; Christian Koeberl; Eugen Libowitzky; Wolf Uwe Reimold

2011-01-01

59

Application of drilling, coring, and sampling techniques to test holes and wells  

USGS Publications Warehouse

The purpose of this manual is to provide ground-water hydrologists with a working knowledge of the techniques of test drilling, auger drilling, coring and sampling, and the related drilling and sampling equipment. For the most part, the techniques discussed deal with drilling, sampling, and completion of test holes in unconsolidated sediments because a hydrologist is interested primarily in shallow-aquifer data in this type of lithology. Successful drilling and coring of these materials usually is difficult, and published research information on the subject is not readily available. The authors emphasize in-situ sampling of unconsolidated sediments to obtain virtually undisturbed samples. Particular attention is given to auger drilling and hydraulic-rotary methods of drilling because these are the principal means of test drilling performed by the U.S. Geological Survey during hydrologic studies. Techniques for sampling areas contaminated by solid or liquid waste are discussed. Basic concepts of well development and a detailed discussion of drilling muds, as related to hole conditioning, also are included in the report. The information contained in this manual is intended to help ground-water hydrologists obtain useful subsurface data and samples from their drilling programs.

Shuter, Eugene; Teasdale, Warren E.

1989-01-01

60

Possible reasons of shock melt deficiency in the Bosumtwi drill cores  

Microsoft Academic Search

Pre-drilling numerical modeling of the Bosumtwi impact event predicted a 200 m thick coherent melt layer, as well as abundant highly shocked target material within the central part of the crater structure. However, these predictions are in disagreement with data from drill core obtained in 2004-2005. Here I provide a brief overview of previous results and discuss possible reasons behind

N. Artemieva

2007-01-01

61

Improved diamond coring bits developed for dry and chip-flush drilling  

NASA Technical Reports Server (NTRS)

Two rotary diamond bit designs, one operating with a chip-flushing fluid, the second including auger section to remove drilled chips, enhance usefulness of tool for exploratory and industrial core-drilling of hard, abrasive mineral deposits and structural masonry.

Decker, W. E.; Hampe, W. R.; Hampton, W. H.; Simon, A. B.

1971-01-01

62

Application of scientific core drilling to geothermal exploration: Platanares, Honduras and Tecuamburro Volcano, Guatemala, Central America.  

National Technical Information Service (NTIS)

Our efforts in Honduras and Guatemala were part of the Central America Energy Resource Project (CAERP) funded by the United States Agency for International Development (AID). Exploration core drilling operations at the Platanares, Honduras and Tecuamburro...

S. J. Goff F. E. Goff G. H. Heiken W. A. Duffield C. J. Janik

1994-01-01

63

Gravelly Sand Interval of the Eyreville Drill Core, Chesapeake Bay Impact Structure, USA  

NASA Astrophysics Data System (ADS)

Results of detailed investigations of the gravelly sand interval (1371-1397 m depth) of the Eyreville drill core including macro- and microscopic observations, modal point counting, X-ray diffraction analyses, and geochemical analyses are presented.

Bartosova, K.; Koeberl, C.; Gier, S.; Horton, J. W.; Mader, D.; Dypvik, H.

2010-03-01

64

Report on ignitability testing of flammable gasses in a core sampling drill string  

SciTech Connect

This document describes the results from testing performed at the Pittsburgh Research Center to determine the effects of an ignition of flammable gasses contained in a core sampling drill string. Testing showed that 1) An ignition of stoichiometric hydrogen and air in a vented 30 or 55 ft length of drill string will not force 28`` or more of water out the bottom of the drill string, and 2) An ignition of this same gas mixture will not rupture a vented or completely sealed drill string.

Witwer, K.S., Westinghouse Hanford

1996-12-01

65

Deep Rotary-Ultrasonic Core Drill for Exploration of Europa and Enceladus  

NASA Astrophysics Data System (ADS)

Since water is an important requisite for life as we know it, likely exobiologic exploration targets in our Solar System include Mars, Europa, and Enceladus, where water/ice is known to exist. Because of oxidizing nature of Mars atmosphere, as well as increased radiation at the surfaces of Mars, Europa and Enceladus, samples must be acquired from the subsurface at greater depths, presenting a great challenge to off-world drilling design. For the past 3 years, we have been developing a prototype wireline coring drill, called the Auto-Gopher, for the capability to acquire samples from hundreds of meters depth. The drill is capable of penetrating both rock and ice. However, because of large geological uncertainty on Mars and issues related to borehole collapse, we specifically target ice formations present on Europa and Enceladus. The main feature of the Auto-Gopher is its wireline operation. The drill is essentially suspended on a tether and the motors and mechanisms are built into a tube that ends with a coring bit. The tether provides the mechanical connection to a rover/lander on a surface as well as power and data communication. Upon penetrating to a target depth, the drill (plus core) is retracted from the borehole by a pulley system (the pulley system can be either on the surface or integrated into a top part of the drill itself). Once on the surface, the core is deposited into a sample transfer system, and the drill is lowered back into the hole in order to drill the next segment. Each segment is typically 10 cm long. Wireline operation sidesteps one of the major drawbacks of traditional continuous drill string systems by obviating the need for multiple drill sections. With traditional continuous drill string systems (the major competition to the Autor-Gopher), new drill sections need to be added to the string as the drill gets deeper. This of course requires multiple drill sections, which add significantly to the mass of the system very quickly, and requires a complicated drill string feeding and coupling mechanism, thus increasing the system complexity. The Auto-gopher has been successfully tested in a lab environment in rock to a depth of 2 meters and in the field. The average drilling power was in the range of 100-150 Watt, while penetration rate was approximately 1 cm/min.

Paulsen, G. L.; Zacny, K.; Bar-Cohen, Y.; Beegle, L. W.; Corsetti, F. A.; Mellerowicz, B.; Badescu, M.; Sherrit, S.; Ibarra, Y.

2012-12-01

66

Optimization of Fluids for Diamond Core Drilling of Silicates.  

National Technical Information Service (NTIS)

The zeta-potential of Westerly granite and its component phases, quartz and microcline in aqueous solutions of dodecyl trimethyl ammonium bromide (DTAB) are reported together with the influence of this surfactant on the rate of drilling these materials wi...

N. H. Macmillan R. E. Jackson W. M. Mularie A. R. C. Westwood

1975-01-01

67

Footwall rotation in an oceanic core complex quantified using reoriented Integrated Ocean Drilling Program core samples  

NASA Astrophysics Data System (ADS)

Oceanic core complexes expose lower crustal and upper mantle rocks on the seafloor by tectonic unroofing in the footwalls of large-slip detachment faults. The common occurrence of these structures in slow and ultra-slow spread oceanic crust suggests that they accommodate a significant component of plate divergence. However, the subsurface geometry of detachment faults in oceanic core complexes remains unclear. Competing models involve either: (a) displacement on planar, low-angle faults with little tectonic rotation; or (b) progressive shallowing by rotation of initially steeply dipping faults as a result of flexural unloading (the "rolling-hinge" model). We address this debate using palaeomagnetic remanences as markers for tectonic rotation within a unique 1.4 km long footwall section of gabbroic rocks recovered by Integrated Ocean Drilling Program (IODP) sampling at Atlantis Massif oceanic core complex on the Mid-Atlantic Ridge (MAR). These rocks contain a complex record of multipolarity magnetizations that are unrelated to alteration and igneous stratigraphy in the sampled section and are inferred to result from progressive cooling of the footwall section over geomagnetic polarity chrons C1r.2r, C1r.1n (Jaramillo) and C1r.1r. For the first time we have independently reoriented drill-core samples of lower crustal gabbros, that were initially azimuthally unconstrained, to a true geographic reference frame by correlating structures in individual core pieces with those identified from oriented imagery of the borehole wall. This allows reorientation of the palaeomagnetic data, placing far more rigorous constraints on the tectonic history than those possible using only palaeomagnetic inclination data. Analysis of the reoriented high temperature reversed component of magnetization indicates a 46° ± 6° anticlockwise rotation of the footwall around a MAR-parallel horizontal axis trending 011° ± 6°. Reoriented lower temperature components of normal and reversed polarity suggest that much of this rotation occurred after the end of the Jaramillo chron (0.99 Ma). The data provide unequivocal confirmation of the key prediction of flexural, rolling-hinge models for oceanic core complexes, whereby oceanic detachment faults initiate at higher dips and rotate to their present day low-angle geometries as displacement increases.

Morris, A.; Gee, J. S.; Pressling, N.; John, B. E.; MacLeod, C. J.; Grimes, C. B.; Searle, R. C.

2009-09-01

68

Application of Ground Penetrating Radar and Geodetics to the Selection of an Ice Core Drill Site on the Kahiltna Glacier of Mount McKinley, Alaska  

NASA Astrophysics Data System (ADS)

Interest in global climate change continues to fuel the search for more sources of quality paleo-climate information in hopes of accurately reconstructing and predicting past and future climates respectively. Ice core records from the Arctic and Antarctic have provided some of the most reliable data for paleo-climate modeling however, the validity of these data and models rely heavily on a number of assumptions regarding ice stratigraphy and glacier structure. Unfortunately, many Arctic valley glaciers are unsuitable for ice core drilling because they exhibit significant melt, ice flow, deformation, and dipping stratigraphy due to their thermal regime and confined flow boundary conditions. Other valley glaciers do exhibit stable accumulation basins with conditions suitable for ice core drilling, however these sites need to be validated through a variety of geophysical and glacio-chemical techniques. A thorough assessment of local meteorological data, snow chemistry, ice flow dynamics, glacier structure, and stratigraphy prior to ice core drilling in a valley glacier is important to determine if the site meets the proper criteria. A glacio-chemical and geophysical reconnaissance of the Kahiltna Glacier on Mount McKinley, Alaska, was performed in 2008 and 2009 to search for an appropriate deep ice core drill location in Central Alaska. Surface velocity measurements from a rapid static GPS survey were coupled with approximately 10 km of 100 MHz GPR profiles to determine surface and subsurface glacier structure and dynamics at a promising drill site near Kahiltna Pass (3078 masl). The GPR profiles reveal a pocket of ice east of Kahiltna Pass with horizontal stratigraphy and 300 meters of ice; based on local accumulation rates and ice flow modeling, this depth of ice likely represents 500 +/- years of climate record. Preliminary geodetic data suggest low velocities (less the 0.1 m/day) at the potential drill site and velocities up to 0.45 m/day 7 km down slope of the drill site. These velocities are comparable to previous velocity measurements recorded on the Kahiltna Glacier. Stratigtraphic complexities do exist in the upper Kahiltna Glacier region; interpretation of these features and their relevance to local ice flow and drill site selection will be discussed.

Campbell, S. W.; Kreutz, K. J.; Wake, C. P.; Osterberg, E. C.; Arcone, S. A.; Volkening, K.; Lurie, M.

2009-12-01

69

3. A SYNOPSIS OF THE BAHAMAS DRILLING PROJECT: RESULTS FROM TWO DEEP CORE BORINGS DRILLED ON THE GREAT BAHAMA BANK 1  

Microsoft Academic Search

Two continuous cores (Unda and Clino) drilled during the initial phase of the Bahamas Drilling Project on top of the west- ern Great Bahama Bank (GBB) penetrated proximal portions of prograding seismic sequences. As such, these cores provide the shallow-water record of sea-level changes and fluid flow of the Bahamas Transect that was completed with the deeper water sites of

G. P. Eberli; P. K. Swart; D. F. McNeill; J. A. M. Kenter; F. S. Anselmetti; L. A. Melim; R. N. Ginsburg

70

Fischer Assays of Oil Shale Drill Cores and Rotary Cuttings from the Piceance Basin, Colorado - 2009 Update  

USGS Publications Warehouse

This CD-ROM includes updated files containing Fischer assays of samples of core holes and cuttings from exploration drill holes drilled in the Eocene Green River Formation in the Piceance Basin of northwestern Colorado. A database was compiled that includes more than 321,380 Fischer assays from 782 boreholes. Most of the oil yield data were analyzed by the former U.S. Bureau of Mines oil shale laboratory in Laramie, Wyoming, and some analyses were made by private laboratories. Location data for 1,042 core and rotary holes, oil and gas tests, as well as a few surface sections are listed in a spreadsheet and included in the CD-ROM. These assays are part of a larger collection of subsurface information held by the U.S. Geological Survey, including geophysical and lithologic logs, water data, and chemical and X-ray diffraction analyses having to do with the Green River oil shale deposits in Colorado, Wyoming, and Utah. Because of an increased interest in oil shale, this CD-ROM disc containing updated Fischer assay data for the Piceance Basin oil shale deposits in northwestern Colorado is being released to the public.

Mercier, Tracey J.; Brownfield, Michael E.; Johnson, Ronald C.; Self, Jesse G.

1998-01-01

71

The ICDP Hotspot Scientific Drilling Program: Overview of geophysical logging and seismic imaging through basaltic and rhyolitic volcanic deposits  

NASA Astrophysics Data System (ADS)

The recently completed ICDP Hotspot drilling program consisted of drilling of three scientific drill holes each to at least 1800 m depth across the Snake River Plain of Idaho. The three boreholes include i) Kimama: thick sequences of basalt flows with sediment interbeds; ii) Kimberley: near surface basalt flows overlying rhyolite deposits, and iii) Mountain Home: geothermally altered basalts overlain by lacustrine sediments. The program consisted of high resolution 2D surface tied to vertical and walk-a-way borehole seismic profiles and an extensive suite of full waveform sonic, ultrasonic televiewer, electrical resistivity, magnetic susceptibility, and hydrogen index neutron logging. There are a number of highlights out of this work. First, seismic imaging beneath basalt flows is a classic problem in reflection seismology and has long been believed to be due to rapid attenuation of the downgoing seismic pulse. Here, however, we observed strong arrivals at all depths suggesting that seismic energy is penetrating such formations and that issues in imaging may be a result of the heterogeneous nature of the formations. Second, the neutron log responses correlate well with the structure of individual basalt flows. High and low backscattered neutron counts correspond to massive low porosity basalt rock and with the higher porosity and sediment filled flow tops, respectively. Third, the ultrasonic borehole televiewer information is being used to orient the nearly complete sets of core in order to obtain information on the azimuths of natural and drilling induced core fractures. This together with examination of borehole breakouts and drilling induced tensile fractures on the wellbore wall will allow for semi-quantitative stress estimates across the Snake River Plain. Finally, the Mountain Home borehole provides an unique opportunity to study the geothermally altered basalts. There are a number of correlations between, for example, the sonic and electrical logs that must relate to the style of alteration.

Schmitt, D. R.; Liberty, L. M.; Kessler, J. A.; Kueck, J.; Kofman, R. S.; Bishop, R. A.; Shervais, J. W.; Evans, J. P.; Champion, D. E.

2012-12-01

72

Fischer Assays of Oil-Shale Drill Cores and Rotary Cuttings from the Greater Green River Basin, Southwestern Wyoming  

USGS Publications Warehouse

Chapter 1 of this CD-ROM is a database of digitized Fischer (shale-oil) assays of cores and cuttings from boreholes drilled in the Eocene Green River oil shale deposits in southwestern Wyoming. Assays of samples from some surface sections are also included. Most of the Fischer assay analyses were made by the former U.S. Bureau of Mines (USBM) at its laboratory in Laramie, Wyoming. Other assays, made by institutional or private laboratories, were donated to the U.S. Geological Survey (USGS) and are included in this database as well as Adobe PDF-scanned images of some of the original laboratory assay reports and lithologic logs prepared by USBM geologists. The size of this database is 75.2 megabytes and includes information on 971 core holes and rotary-drilled boreholes and numerous surface sections. Most of these data were released previously by the USBM and the USGS through the National Technical Information Service but are no longer available from that agency. Fischer assays for boreholes in northeastern Utah and northwestern Colorado have been published by the USGS. Additional data include geophysical logs, groundwater data, chemical and X-ray diffraction analyses, and other data. These materials are available for inspection in the office of the USGS Central Energy Resources Team in Lakewood, Colorado. The digitized assays were checked with the original laboratory reports, but some errors likely remain. Other information, such as locations and elevations of core holes and oil and gas tests, were not thoroughly checked. However, owing to the current interest in oil-shale development, it was considered in the public interest to make this preliminary database available at this time. Chapter 2 of this CD-ROM presents oil-yield histograms of samples of cores and cuttings from exploration drill holes in the Eocene Green River Formation in the Great Divide, Green River, and Washakie Basins of southwestern Wyoming. A database was compiled that includes about 47,000 Fischer assays from 186 core holes and 240 rotary drill holes. Most of the oil yield data are from analyses performed by the former U.S. Bureau of Mines oil shale laboratory in Laramie, Wyoming, with some analyses made by private laboratories. Location data for 971 Wyoming oil-shale drill holes are listed in a spreadsheet that is included in the CD-ROM. These Wyoming Fischer assays and histograms are part of a much larger collection of oil-shale information, including geophysical and lithologic logs, water data, chemical and X-ray diffraction analyses on the Green River oil-shale deposits in Colorado, Utah, and Wyoming held by the U.S. Geological Survey. Because of an increased interest in oil shale, this CD-ROM containing Fischer assay data and oil-yield histograms for the Green River oil-shale deposits in southwestern Wyoming is being released to the public. Microsoft Excel spreadsheets included with Chapter 2 contain the Fischer assay data from the 426 holes and data on the company name and drill-hole name, and location. Histograms of the oil yields obtained from the Fischer assays are presented in both Grapher and PDF format. Fischer assay text data files are also included in the CD-ROM.

U.S. Geological Survey Oil Shale Assessment Team

2008-01-01

73

Geophysical constraints on extensional deformation at slow-spreading rate ridges and the evolution of oceanic core complexes  

NASA Astrophysics Data System (ADS)

Oceanic core complexes expose lower crustal and upper mantle rocks on the seafloor by tectonic unroofing in the footwalls of large-slip extensional detachment faults. The common occurrence of these structures in slow and ultra-slow spreading oceanic crust suggests they accommodate a significant component of plate divergence. However, the sub-surface geometry of oceanic detachment faults remains unclear. Competing models involve either: (a) displacement on planar, low-angle faults with little tectonic rotation; or (b) progressive shallowing by rotation of initially steeply dipping faults as a result of flexural unloading (the "rolling-hinge" model). We address this debate using paleomagnetic remanences to test for tectonic rotation of a unique 1.4 km long footwall section of gabbroic rocks recovered by Integrated Ocean Drilling Program (IODP) Expedition 304/305 to Atlantis Massif oceanic core complex on the Mid Atlantic Ridge (MAR). This forms an inside-corner bathymetric high at the intersection of the Atlantis Transform Fault and the MAR. The central dome of the massif exposes the corrugated detachment fault surface, which has tectonically unroofed a faulted and complexly layered footwall section dominated by gabbroic lithologies with minor ultramafic rocks. The core (IODP Hole U1309D) reflects the interplay between magmatism and deformation prior to, during, and subsequent to a period of footwall displacement and denudation associated with slip on the detachment fault. Palaeomagnetic remanence directions are routinely used as markers for tectonic rotation in a variety of tectonic settings, However, in ODP and IODP hard rock core materials their utility is limited by the lack of azimuthal control on the orientation of core samples. Individual core pieces are free to rotate within the core barrel, effectively randomising remanence declinations and allowing only the inclination of the magnetic vector to be used in tectonic analyses. In these circumstances, tectonic rotation may be inferred from differences between observed and reference inclinations, but the amount of rotation and the orientation of the rotation axis cannot be constrained directly. Robust, quantitative constraints on tectonic rotation parameters can only be obtained from fully oriented palaeomagnetic data (i.e. both remanence declination and inclination), yet current IODP hard rock drilling technologies do not permit collection of oriented drill core samples. For the first time we have overcome this limitation by independently reorienting core pieces to a true geographic reference frame by correlating structures within individual pieces with those identified from oriented geophysical imagery of the borehole wall. This allows reorientation of paleomagnetic data and subsequent tectonic interpretation without the need for a priori assumptions on the azimuth of the rotation axis. The resulting dataset from Atlantis Massif indicates a 46°±6° counterclockwise rotation of the footwall around a MAR-parallel horizontal axis trending 011°±6°. This provides unequivocal confirmation of the key prediction of flexural, rolling-hinge models for oceanic core complexes. The data demonstrate that the Atlantis Massif detachment fault initiated at a dip of at least 50° and subsequently rotated to its present day low angle geometry during extensional deformation and unroofing.

Morris, Antony; Pressling, Nicola; Gee, Jeffrey; John, Barbara; MacLeod, Christopher

2010-05-01

74

Interpretation of geology, geophysics and hydrochemistry for selection of geothermal drilling sites, Canon de San Diego Grant, Sandoval county, New Mexico  

SciTech Connect

This project began in mid-1977 as an evaluation of the geology and hydrogeology of the Canon de San Diego Grant for Sunoco Energy Development Co. (Sunedco) and evolved late in 1977, at Sunedco's direction, into a more comprehensive study of geophysical, geologic and hydrogeochemical data. This has been used to select sites for the possible drilling of deep geothermal wells.

Koenig, J.B.; McIntyre, J.R.; Klein, C.W.; Beyer, J.H.

1978-11-01

75

Scientific Plan for Deep Ice Core Drilling in Central Greenland (GISP 2 - Greenland Ice Sheet Project).  

National Technical Information Service (NTIS)

Ice sheets are natural archival systems that continuously collect and preserve the physical and chemical history of the Earth's atmosphere. Ice cores drilled from the ice sheets offer a practical way to study the layers of ice. Deep ice cores have been dr...

E. Mosley-Thompson A. J. Gow M. M. Herron K. Jezek B. Kamb

1985-01-01

76

Tecuamburro Volcano, Guatemala geothermal gradient core hole drilling, operations, and preliminary results.  

National Technical Information Service (NTIS)

A geothermal gradient core hole (TCB-1) was drilled to a depth of 700+ m at the Tecuamburro geothermal site, Guatemala during February and March, 1990. The core hole is located low on the northern flank of the Tecuamburro Volcano complex. Preliminary anal...

S. Goff G. Heiken F. Goff J. Gardner W. Duffield

1990-01-01

77

U. S. Geological Survey core drilling on the Atlantic shelf  

Microsoft Academic Search

The first broad program of scientific shallow drilling on the US Atlantic continental shelf has delineated rocks of Pleistocene to Late Cretaceous age, including phosphoritic Miocene strata, widespread Eocene carbonate deposits that serve as reflective seismic markers, and several regional unconformities. Two sites, off Maryland and New Jersey, showed light hydrocarbon gases having affinity to mature petroleum. Pore fluid studies

J. C. Hathaway; C. W. Poag; P. C. Valentine; R. E. Miller; D. M. Schultz; F. T. Manheim; F. A. Kohout; M. H. Bothner; D. A. Sangrey

1979-01-01

78

Chattanooga shale (Devonian and Mississippian) from the Tennessee Division of Geology: U. S. Department of Energy cored drill holes Number 4 and 5, Hawkins County, Tennessee  

SciTech Connect

The Tennessee Division of Geology under contract to the Morgantown Energy Technology Center of the US Department of Energy has drilled eight NX coreholes in eastern Tennessee. The coring program was designed to retrieve continuous cores for a detailed study of the character of the Chattanooga Shale. The geophysical wire-line logging of the NX drill holes was performed by the US Geological Survey. The lithologic and wire-line log data in conjunction with two seismic surveys will be used to evaluate the hydrocarbon potential of the Chattanooga Shale in northeastern Tennessee. The purpose of this report is to present a detailed lithologic description and gamma-ray log of the Tennessee Division of Geology and US Department of Energy cored drill holes no. 4 and 5 (TDG-DOE no. 4 and no. 5). In spite of the overlap, no distinct marker beds were found to facilitate a positive correlation between the two cores. Reconstruction of the total Chattanooga section was based on detailed field mapping of the uppermost dark-gray shale below the base of the Grainger Formation and the projection of the beds. The total thickness of the Chattanooga Shale at the coring locations is estimated to be 1650 to 1700 ft.

Roen, J.B.; Wallace, L.G.; Milici, R.C.

1980-01-01

79

Improving the Accuracy of Core Location and Recovery Estimates Through the Integration of Core Data, Wireline Logs and Drilling Parameters: an Example From IODP Expedition 310, Tahiti Sea Level  

NASA Astrophysics Data System (ADS)

In palaeoclimate and sea-level studies accurate depth positioning of core pieces is critical in assessing the usefulness of a specific drill site. The location and amounts of core recovered during a drilling program can often place severe constraints on the subsequent applications of core measurements. The principle objectives of Expedition 310 are to establish the course of postglacial sea level rise at Tahiti in the South Pacific, to define sea surface temperature (SST) variations for the region over the period 20 to10 ka, and to analyse the impact of sea level changes on reef growth and geometry. Average conventionally-calculated core recovery for the 37 boreholes drilled during this expedition is 57.47 percent, although for an individual borehole core recovery is highly variable. Depth inaccuracies increase as recovery falls below 100 percent as, by convention, core is placed at the top of the core barrel run from which it was recovered. Careful integration of datasets can improve the positioning of core. The Expedition 310 logging programme included the collection of high resolution optical and acoustic images. Visual correlation of the recovered core with these image logs provides an extremely effective method of integrating these datasets. Comparison of drilling parameters (rate of drilling, pullback pressure and torque on bit) with the downhole logs indicates a clear correlation between these datasets and allows the logging data to be accurately matched to the drilling data. The final integrated depths comprise the underlying framework for all subsequent scientific analyses of recovered core employing interpretations based on depth. There are two principle outcomes of the integration process: (i) Accurate depth positioning can be achieved. In coral reefs where regions of high porosity and large void spaces are common, without careful integration of discrete core pieces with continuous records of the nature of the borehole, large depth errors can result and propagate through analyses. (ii) Core recoveries can be accurately estimated. Estimates based on core alone cannot take into consideration meso or macro scale porosities. Utilising continuous geophysical measurements allows areas of high porosity to be identified and incorporated into the calculation of recovery percentages.

Inwood, J.; Brewer, T.; Braaksma, H.; Pezard, P.

2007-12-01

80

Petrologic studies of drill cores USW-G2 and UE25b-1H, Yucca Mountain, Nevada  

SciTech Connect

The tuffs of the Nevada Test Site are currently under investigation as a possible deep geologic site for high-level radioactive waste disposal. This report characterizes tuff retrieved in core from two drill holes, USW-G2 and UE25b-1H, at the Yucca Mountain block. The USW-G2 drill core is from the northernmost extent of the block, whereas UE25b-1H is adjacent to an earlier drill hole, UE25a-1. The drill cores USW-G2 and UE25b-1H bottomed at 6000 and 4200 ft, respectively. Petrographic and x-ray diffraction studies of the two drill cores are presented in this report and indicate that tuffs (composed primarily of variably welded ash flows) are partially recrystallized to secondary minerals. Correlations of stratigraphy are also made with previous drill cores from Yucca Mountain.

Caporuscio, F.; Vaniman, D.; Bish, D.; Broxton, D.; Arney, B.; Heiken, G.; Byers, F.; Gooley, R.; Semarge, E.

1982-07-01

81

Paleomagnetism of the Astrobiology Drilling Project 8 drill core, Pilbara, Western Australia: implications for the early geodynamo and Archean tectonics  

NASA Astrophysics Data System (ADS)

Paleomagnetic measurements from the Archean Pilbara craton have recently been used to argue for the presence of a substantial magnetic field at 3.2 Ga (Tarduno et al., 2007), as well as for extremely fast plate motions or true polar wander (Strik et al., 2003, Suganuma et al., 2006). Paleomagnetic records in the Archean are fundamentally limited by the scarcity of well-preserved, low metamorphic grade Archean rocks. Where such rocks are exposed, paleomagnetic sampling is often difficult or impossible due to pervasive lightning remagnetization and deep weathering of the cratonic surface. More pristine samples can potentially be obtained from shallow drill cores like those obtained by the Astrobiology Drilling Project (ABDP). We present a paleomagnetic analysis of the ~350 m deep ABDP-8 drill core, which was drilled in the East Strelley greenstone belt and which penetrated the Double Bar Formation of the Warrawoona Group, as well as the unconformably overlying Euro Basalt and Strelley Pool Chert units of the Kelly Group. Full sample orientation (declination and inclination) was achieved through the use of a Ballmark orientation system. A strong drilling overprint was removed for most samples by alternating field demagnetization to 20 mT. Subsequent thermal demagnetization revealed single-polarity magnetic directions within the Euro Basalt and Double Bar Formation carried by magnetite. The directions from these two Formations are statistically different to >95% confidence, which constitutes a positive unconformity test and indicates that the Euro Basalt direction is primary. Upon tilt correction, the ~3.34-3.37 Ga Euro Basalt direction is indistinguishable from the tilt-corrected direction found previously in the ~3.46 Ga Duffer Formation of the Warrawoona Group (McElhinny and Senanayake, 1980). The Euro Basalt direction, if taken at face value, implies small relative motion of the Pilbara Craton from ~3.46 Ga to ~3.34 Ga. This is inconsistent with the apparent polar wander path presented for the ~3.46 Ga Marble Bar Chert Member of the Towers Formation (Suganuma et al., 2006). The lack of reversals in the sequence is consistent with a low reversal frequency in early Earth history, as has been suggested by dynamo models for the Earth with a small inner core (Coe and Glatzmaier, 2006).

Bradley, K.; Weiss, B.; Carporzen, L.; Anbar, A.; Buick, R.

2008-12-01

82

Diaplectic transformation of minerals: Vorotilov drill core, Puchezh-Katunki impact crater, Russia  

NASA Technical Reports Server (NTRS)

The Vorotilov core was drilled in the central uplift of the Puchezh-Katunki astrobleme to a depth of 5.1 km. Impactites are revealed in the rocks of the core beginning from a depth of 366 m: suevites (66 m), allogenic breccias (112 m), and autogenic breccias (deeper than 544 m). These rocks are represented by shocked-metamorphic gneisses, schists, amphibolites of Archean age, and magmatic rocks (dolerites, olivines, and peridotites) that lie between them.

Feldman, V. I.

1992-01-01

83

Inert gas stratigraphy of Apollo 15 drill core sections 15001 and 15003  

NASA Technical Reports Server (NTRS)

Rare gase contents were studied in Apollo 15 drill core sections corresponding to 207 to 238 and 125 to 161-cm depths, with respect to layering of the core, turnover on a centimeter scale, and cosmic proton bombardment history. Trapped gas abundance was established in all samples, the mean grain size being a major factor influencing the absolute rare gas contents. Analysis of the results suggests that the regolith materials were exposed to galactic and solar cosmic rays long before their deposition.

Huebner, W.; Kirsten, T.; Heymann, D.

1973-01-01

84

The remarkable chemical uniformity of Apollo 16 layered deep drill core section 60002  

NASA Technical Reports Server (NTRS)

Atomic absorption and colorimetric spectrophotometers were used to determine major- and minor-element abundances in 12 samples from layered section 60002 of the Apollo 16 deep drill core. It is suggested that gardening of a relatively thick local unit produced the layering in this section in such a manner that the proportions of materials of different compositions remained virtually unchanged.

Nava, D. F.; Philpotts, J. A.; Lindstrom, M. M.; Schuhmann, P. J.; Lindstrom, D. J.

1976-01-01

85

Application of scientific core drilling to geothermal exploration: Platanares, Honduras and Tecuamburro Volcano, Guatemala, Central America  

Microsoft Academic Search

Our efforts in Honduras and Guatemala were part of the Central America Energy Resource Project (CAERP) funded by the United States Agency for International Development (AID). Exploration core drilling operations at the Platanares, Honduras and Tecuamburro Volcano, Guatemala sites were part of a geothermal assessment for the national utility companies of these countries to locate and evaluate their geothermal resources

S. J. Goff; F. E. Goff; G. H. Heiken; W. A. Duffield; C. J. Janik

1994-01-01

86

Low and high temperature susceptibility data of the Chicxulub Yax-1 drill core: link to magnetic carriers.  

NASA Astrophysics Data System (ADS)

Temperature variations of weak-field magnetic susceptibility of Yax-1 drill core of the Chicxulub impact structure were examined in order to characterize magnetic minerals carrying the induced and remanent magnetization. Measurements were carried out at the Solid Earth Geophysics Laboratory, University of Helsinki, using KLY-3 kappabridge coupled with CS-3 temperature control. The applied temperature ranged from -192 °C to room temperature (low temperature treatment) and from ambient temperature to 700 °C (high temperature treatment). Both air and argon environments were used at high temperatures. Preliminary results show that in the impact samples there is a distinct change in the slope of the susceptibility vs. temperature curve at 450 °C. This possibly corresponds to titanomagnetite with relatively low Ti content. In some samples the data show also presence of nearly pure magnetite and/or pyrrhotite. Fe-Ti-oxides has been observed in impact rocks also before (Pilkington et al. 2004). Paleomagnetic data have previously (Elbra et al. 2004) shown that there are often two polarities present in same impact samples. Current data reveal also two magnetic carriers. We are now looking whether the polarity observations can be linked to these magnetic carriers. References Elbra, T., Pesonen, L.J., Kenkmann, T., Smit, J., 2004. A new preliminary paleomagnetic and petrophysical data of the Yaxcopoil drillcore, Chicxulub impact, Mexico. Geophysical Research Abstracts, EGU General Assembly, Nice, France. Volume 6. ISSN: 1029-7006. Pilkington, M., Ames, D. E.,Hildebrand A. R., 2004. Magnetic mineralogy of the Yaxcopoil-1 core, Chicxulub. Meteoritics & Planetary Science 39, Nr 6, 831-841

Elbra, T.; Pesonen, L. J.; Rebolledo-Vieyra, M.

2005-05-01

87

Al26 depth profile in Apollo 15 drill core  

Microsoft Academic Search

Accelerator mass spectrometry is used in a study of galactic cosmic ray production profiles based on cosmic ray-produced Al-26 in the Apollo 15 long core. The results, which are in general agreement with earlier nondestructive counting data, are of significantly higher precision, yet systematically lower. The half-attenuation length for Al-26 production is presently calculated to be 122 g\\/sq cm, after

K. Nishiizumi; J. R. Arnold; J. Klein; R. Middleton

1984-01-01

88

Pervasive, high temperature hydrothermal alteration in the RN-17B drill core, Reykjanes Geothermal System-Iceland Deep Drilling Project  

NASA Astrophysics Data System (ADS)

In November 2008, 9.5 m of core were recovered from Reykjanes production well RN-17B at a depth of 2800m. The core consists mainly of hyaloclastite breccias, hetrolithic breccias with clasts of crystalline basalt, and volcaniclastic sandstones/siltstones. Much of the material appears to have been transported and redeposited, but homolithic breccias and hyaloclastites, some with upright flow lobes of basalt with quenched rims, are interpreted to have erupted in situ. Fine-scale features (glass rims, quench crystals, vesicles, phenocrysts) are well preserved, but all lithologies are pervasively hydrothermally altered such that primary clinopyroxene is ubiquitously uralitized and primary plagioclase (An42-80) is replaced by albite and/or more calcic plagioclase. In contrast, cuttings of similar lithologies, recovered by rotary drilling in intervals immediately above and below the core, exhibit much lesser degrees of hydrothermal alteration and commonly contain igneous plagioclase and clinopyroxene. Vitric clasts in the core are recrystallized into aggregates of chlorite and actinolite. In some breccias, cm-scale metadomains are composed of patchy albite or actinolite/magnesiohornblende giving the core a green and white spotted appearance. Minor amounts (<1%) of disseminated pyrite occur throughout the core, but two intervals with more abundant sulfide contain chalcopyrite and sphalerite in addition to pyrite. Amygdales and vugs in the breccias, initially filled with chlorite, actinolite, epidote, and/or albite, have been partly overprinted with hornblende and anorthite. The core is cut in places by < 1 cm- wide veins composed of early epidote + actinolite + titanite and later anorthite + magnesiohornblende/pargasite. Quartz is not present in any alteration domains observed in the core, although it is reported from virtually all of the cutting intervals above and below the cored section. Seawater-basalt reaction calculations suggest that albite formed during early burial at T<300 is replaced by more calcic plagioclase at higher temperature. Texturally, hydrothermal anorthite (An90-98) and pargasite (up to 13.5 wt % Al2O3) appear to have grown at the expense of earlier formed epidote + chlorite + actinolite. Measured downhole temperature at 2800m in RN-17B following reequilibration was 320°C, although amphibole-plagioclase geothermometry imply that anorthite + pargasite, if in equilibrium, should have formed at much higher temperatures. The differences in extent and intensity of alteration inferred from examination of cuttings compared to drill core indicate that selective recovery and mixing of cuttings from multiple depths may be a larger problem than presently appreciated. Previous work has shown that the Reykjanes geothermal system has evolved from a meteoric water-dominated system to higher salinity system dominated by seawater-recharge. The paragenetic relationships that are discernible in the core hopefully will allow us to quantify the alteration processes related to the change in salinity.

Zierenberg, R. A.; Schiffman, P.; Marks, N. E.; Reed, M. H.; Elders, W. A.; Fridleifsson, G. O.

2010-12-01

89

Hyaloclastites and the slope stability of Hawaiian volcanoes: Insights from the Hawaiian Scientific Drilling Project's 3-km drill core  

NASA Astrophysics Data System (ADS)

Core samples recovered during the Hawaiian Scientific Drilling Project (HSDP) drilling project reveal that the upper 1 km of the submarine flank of Mauna Kea is comprised mainly of hyaloclastites. Progressive, very low-temperature alteration of these hyaloclastites has been accompanied by systematic transformations in physical properties of these deposits. Hyaloclastite deposits which directly underlie ca. 1 km of subaerially-emplaced lavas are very poorly consolidated. But over a depth interval of ca. 500 m, compaction and, especially, precipitation of zeolitic, pore-filling cements associated with palagonitization of sideromelane, have eliminated porosity as well as promoted the consolidation of these hyaloclastites. The latter is reflected in unconfined compressive strengths which increase from mean values, respectively, of 2.5 and 4.6 MPa in weakly consolidated, smectite-rich hyaloclastites from the incipient (1080 to 1335 mbsl) and smectitic (1405-1573 mbsl) alteration zones, to a mean value of 10.0 MPa in the more highly consolidated hyaloclastites of the palagonitic zone of alteration (from 1573 mbsl to the bottom of the drill hole). Conversely, overlying, intercalated, and underlying lava flows are generally much less altered, and have mean compressive strengths which are 1 to 2 orders of magnitude greater then hyaloclastites at equivalent depths. The shear strengths of the hyaloclastites also increase with depth and grade of alteration, but are uniformly and substantially lower in the lavas. Those hyaloclastites exhibiting the highest grade of alteration (i.e., palagonitic) also exhibit the highest measured strengths, and thus the alteration of hyaloclastites appears to strengthen as opposed to weaken the flanks of the edifice. However, the contrast in strength between hyaloclastites and lavas may be a primary factor in localizing destabilization, and the zones of weak and poorly consolidated hyaloclastites may facilitate slumping by servings as hosts for shallow detachment surfaces on the unsupported flanks of these volcanoes.

Schiffman, Peter; Watters, Robert J.; Thompson, Nick; Walton, Anthony W.

2006-03-01

90

Bacterial study of Vostok drilling fluid: the tool to make ice core finding confident  

NASA Astrophysics Data System (ADS)

Decontamination of Vostok ice core is a critical issue in molecular biology studies. Core surface contains a film of hardly removable 'dirty' drilling fluid representing a mixture of polyhydrocarbons (PHC) including polyaromatic hydrocarbons (PAH) and freon. To make ice microbial finding more confident the original Vostok drilling fluid sampled from different depths (110m - 3600m) was analyzed for bacterial content by ribosomal DNA sequencing. Total, 33 clones of 16S ribosomal DNA were recovered from four samples of drilling fluid at 110, 2750, 3400, and 3600m leading to identification of 8 bacterial species. No overlapping was observed even for neighboring samples (3400m and 3600m). At present four major bacteria with the titer more than 103-104 cells per ml (as estimated from PCR results) are identified. Among them we found: unknown representative of Desulfobacteraceae which are able to oxidize sulphates and degrade benzenes (110m); PAH-degrading alpha-proteobacterium Sphingomonas natatoria (3400m); alpha-proteobacterium representing closely-related group of Sphingomonas sp. (e.g., S. aurantiaca) which are able to degrade PAH as well, and human pathogen closely related to Haloanella gallinarum of CFB group (3600m). Four additional species were revealed as single clones and showed relatedness to human pathogens and saprophytes as well as soil bacteria. These bacteria may represent drilling fluid contaminants introduced during its sampling or DNA extraction procedure. Of four major bacteria revealed, one species, Sphingomonas natatoria, has been met by us in the Vostok core from 3607 m depth (AF532054) whereas another Sphingomonas sp. which we refer to as S. aurantiaca was found in Antarctic microbial endolithic community (AF548567), hydrocarbon-containing soil near Scott Base in Antarctica (AF184221) and even isolated from 3593m Vostok accretion ice (AF324199) and Taylor Dome core (AF395031). The source for major human pathogen-related bacteria is rather uncertain indicating that very unusual microbes can be contained in a drilling fluid. All this testifies that kerosene film is indeed hard to remove and everyone should be aware on bacteria introduced with any drilling fluid. Our results demonstrate the necessity to have a drilling fluid data base when studying the microbial contents of ice cores.

Alekhina, I. A.; Petit, J. R.; Lukin, V. V.; Bulat, S. A.

2003-04-01

91

Paleomagnetic Reorientation of Structural Elements in Drill Cores: an example from Tolhuaca Geothermal Field  

NASA Astrophysics Data System (ADS)

Reorientation of mesoscopic faults, veins and fractures recovered from drilling is critical to construct reliable structural models that can account for their architecture and deformation regime. However, oriented cores are expensive and time consuming to drill. Some techniques achieve reorientation by introducing tools into the borehole. Problems arise when boreholes are unstable or collapse. One alternative technique allowing reorientation is to obtain reliable paleomagnetic vectors to reorient each core piece after drilling. Here, we present stable and reliable remnant magnetic vectors calculated from the Tol-1 core to analyze the geometry of the fracture network and its relationship to regional tectonic. Tol-1 core is a vertical, 1073 m deep geothermal well, drilled at the Tolhuaca Geothermal Field in the Southern Volcanic Zone of the Andes by MRP Geothermal Chile Ltda (formerly GGE Chile SpA) in 2009. The core consists of basaltic/andesitic volcanic rocks with subordinate pyroclastic/volcaniclastic units, with probable Pleistocene age. Fault planes with slickenlines and mineral fiber kinematic indicators are common in the upper 700 m of the core. Calcite, quartz and calcite-quartz veins are recognized along of entire core, whereas epidote-quartz and calcite-epidote veins occur in the last 350 m, minor chlorite, anhydrite and clay-minerals are present. Orientations of structural features in the core were measured with a goniometer using the core's axis and a false north for each piece; hence, orientation data has a false strike but a real dip. To achieve total reorientation of the pieces, we collected 200 standard-size paleomagnetic specimens, ensuring that at least four of them were recovered from continuous pieces. Thermal (up to 700°C) and alternating field demagnetization (up to 90mT on steps of 2mT) methods were used to isolate a stable remnant magnetization (RM) vector, and each technique yielded similar results. RM vectors were recovered between 0 to 25mT, and between 0 to 625°C. The declination of RM vectors was used to bring pieces to a common anchor orientation calculated through the Geocentric Axial Dipole Model (GAD). The paleomagnetic technique proved to be reliable to reorient the Tol-1 core. Structural analyses along the core show N50-60E-striking preferential vein orientation. In addition, N40-50E- and N60-70W-striking preferential fault orientations were identified. Kinematic analysis of fault-slip data shows a N60E-striking bulk fault plane solution with normal strain regime. The veins and faults orientation show strain axes compatible with published regional stress field (?max N238E).

Perez-Flores, P.; Veloso, E. E.; Cembrano, J. M.; Sánchez, P.; Iriarte, S.; Lohmar, S.

2013-12-01

92

Characteristics of crushed rocks observed in drilled cores in landslide bodies located in accretionary complexes  

NASA Astrophysics Data System (ADS)

The recent development of high-quality boring, which uses foam surfactants, has made it possible to examine the detailed geological constitution and structure of landslide bodies. However, geological information related to landslides has not been obtained appropriately even from undisturbed high-quality drilled cores. Moreover, it has been difficult to distinguish between rocks crushed by landslide movement and the fault breccia in accretionary complexes. We examined the detailed geology of high-quality drilled cores of landslide bodies on the Shimanto Belt and the Chichibu Belt. The fault breccia near the landslide bodies was found to exhibit planar fabrics while the crushed breccias in the landslide bodies showed a random fabric. We discovered that classifying the degree of crushing and inspecting the planar fabrics of rocks are effective in the geological determination of landslide bodies.

Wakizaka, Yasuhiko

2013-10-01

93

Lithologic and geophysical logs of drill holes Felderhoff Federal 5-1 and 25-1, Amargosa Desert, Nye County, Nevada  

SciTech Connect

Two wildcat oil and gas exploration holes drilled in 1991 on the northern edge of the Amargosa Desert penetrated Tertiary and Quaternary sedimentary rocks, alluvium, and basalt, possible Tertiary volcanic or volcaniclastic rocks, and Tertiary (?) and Paleozoic carbonate rocks. The easternmost of the two holes, Felderhoff-Federal 5-1, encountered about 200 feet of alluvium, underlain by 305 feet of basalt breccia and basalt, about 345 feet of probable Tertiary tuffaceous sedimentary rocks, and 616 feet of dense limestone and dolomite of uncertain age. Drill hole 25-1 penetrated 240 feet of alluvium and marl (?), and 250 feet of basalt breccia (?) and basalt, 270 feet of tuff (?) and/or tuffaceous sedimentary rocks, 360 feet of slide blocks (?) and large boulders of Paleozoic carbonate rocks, and 2,800 feet of Paleozoic limestone and dolomite. The two drill holes are located within a northerly trending fault zone defined largely by geophysical data; this fault zone lies along the east side of a major rift containing many small basalt eruptive centers and, farther north, several caldera complexes. Drill hole 25-1 penetrated an inverted paleozoic rock sequence; drill hole 5-1 encountered two large cavities 24-inches wide or more in dense carbonate rock of uncertain, but probable Paleozoic age. These openings may be tectonic and controlled by a regional system of northeast-striking faults.

Carr, W.J.; Grow, J.A. [Geological Survey, Denver, CO (United States); Keller, S.M. [Science Applications International Corp., Golden, CO (United States)

1995-10-01

94

Neutron capture effects on samarium, europium, and gadolinium in Apollo 15 deep drill-core samples  

Microsoft Academic Search

The isotopic compositions of Sm and Gd in seven lunar samples from the Apollo 15 deep drill core were determined to discuss the effects of neutron capture near the lunar surface. Large isotopic deviations of 150Sm\\/149Sm, 156Gd\\/155Gd and 158Gd\\/157Gd derived from neutron capture effects were observed in all samples. Although neutron capture products in lunar samples were extensively in the

Hiroshi Hidaka; Mitsuru Ebihara; Shigekazu Yoneda

2000-01-01

95

Mineralogic variation in drill core UE-25 UZ{number_sign}16, Yucca Mountain, Nevada  

SciTech Connect

Quantitative X-ray powder diffraction methods have been used to analyze 108 samples from drill core UE-25 UZ{number_sign}16 at Yucca Mountain, Nevada. This drill hole, located within the imbricate fault zone east of the potential Yucca Mountain repository site, confirms the authors` previous knowledge of gross-scale mineral distributions at Yucca Mountain and provides insight into possible shallow pathways for hydrologic recharge into the potential host rock. Analyses of samples from UE-25 UZ{number_sign}16 have shown that the distribution of major zeolitized horizons, of silica phases, and of glassy tuffs are similar to those noted in nearby drill cores. However, the continuous core and closer sample spacing in UE-25 UZ{number_sign}16 provide a more exact determination of mineral stratigraphy, particularly in hydrologically important units such as the Paintbrush bedded tuffs above the Topopah Spring Tuff and in the upper vitrophyre of the Topopah Spring Tuff. The discovery of matrix zeolitization in the devitrified Topopah Spring Tuff of UE25 UZ{number_sign}16 shows that some unexpected mineralogic features can still be encountered in the exploration of Yucca Mountain and emphasizes the importance of obtaining a more complete three-dimensional model of Yucca Mountain mineralogy.

Chipera, S.J.; Vaniman, D.T.; Carlos, B.A.; Bish, D.L.

1995-02-01

96

Integrated Geologic, Hydrologic, and Geophysical Investigations of the Chesapeake Bay Impact Structure, Virginia, USA: A Multi-Agency Program  

NASA Astrophysics Data System (ADS)

The Chesapeake Bay impact structure is the focus of an ongoing federal-state-local research program. Recent core drilling and geophysical surveys address the formative processes and hydrogeologic properties of this major 'wet-target' impact.

Gohn, G. S.; Bruce, T. S.; Catchings, R. D.; Emry, S. R.; Johnson, G. H.; Levine, J. S.; McFarland, E. R.; Poag, C. W.; Powars, D. S.

2001-03-01

97

Integrated Geologic, Hydrologic, and Geophysical Investigations of the Chesapeake Bay Impact Structure, Virginia, USA: A Multi-Agency Program  

Microsoft Academic Search

The Chesapeake Bay impact structure is the focus of an ongoing federal-state-local research program. Recent core drilling and geophysical surveys address the formative processes and hydrogeologic properties of this major 'wet-target' impact.

G. S. Gohn; T. S. Bruce; R. D. Catchings; S. R. Emry; G. H. Johnson; J. S. Levine; E. R. McFarland; C. W. Poag; D. S. Powars

2001-01-01

98

Study of drill core from the East Chaco Canyon area, San Juan Basin. Part I. Geochemical studies  

Microsoft Academic Search

The East Chaco Canyon (ECC) drilling program was undertaken by the US Department of Energy (DOE) to compare the Westwater Canyon Member of the Morrison Formation from the ECC part of the San Juan Basin with the highly uranium mineralized Westwater Canyon Member of the Grants Mineral Belt (GMB). Core from fifteen DOE drill holes was made available in part

Brookins

1979-01-01

99

Geophysical signatures of past and present hydration within a young oceanic core complex  

NASA Astrophysics Data System (ADS)

logging at the Atlantis Massif oceanic core complex provides new information on the relationship between the physical properties and the lithospheric hydration of a slow-spread intrusive crustal section. Integrated Ocean Drilling Program Hole U1309D penetrates 1.4 km into the footwall to an exposed detachment fault on the 1.2 Ma flank of the mid-Atlantic Ridge, 30°N. Downhole variations in seismic velocity and resistivity show a strong correspondence to the degree of alteration, a recorder of past seawater circulation. Average velocity and resistivity are lower, and alteration is more pervasive above a fault around 750 m. Deeper, these properties have higher values except in heavily altered ultramafic zones that are several tens of meters thick. Present circulation inferred from temperature mimics this pattern: advective cooling persists above 750 m, but below, conductive cooling dominates except for small excursions within the ultramafic zones. These alteration-related physical property signatures are probably a characteristic of gabbroic cores at oceanic core complexes.

Blackman, Donna K.; Slagle, Angela; Guerin, Gilles; Harding, Alistair

2014-02-01

100

A Long Record of Tropical Glaciation and Climate Change in Drill Cores From Lake Titicaca  

NASA Astrophysics Data System (ADS)

A long and continuous continental record of climate change from the tropics could provide a measure of climate variability and pacing comparable to marine and high-latitude terrestrial records. Lake Titicaca (16° S, 69° W), one of the largest extant lakes in South America, is located at 3810 m between the eastern and western cordillera of the Peruvian-Bolivian Andes. In April-May 2001 we used the GLAD800 drill rig to recover 625 m of sediment core from three sites in the lake. Our principal drill site in 235 m water depth yielded a 136 m core. Five intervals of sediments high in magnetic susceptibility are separated by thinner intervals of sediments with low magnetic susceptibility characterized by relatively high organic (0.2 to 12.9%) and inorganic carbon (0.2 to 9.8%). Radiocarbon analysis of bulk organic matter from the core catchers indicates that the most recent interval of high magnetic susceptibility lasted from ca. 22,000 to <52,000 14C yr BP. Our previous work on piston cores from Lake Titicaca indicated that sediments high in magnetic susceptibility and low in organic carbon were associated with a greater influx of glacially derived silts from the neighboring cordillera. In contrast, sediments with high organic and inorganic carbon and low magnetic susceptibility represented time periods when glaciers had retreated and perhaps disappeared entirely from the watershed. We believe that the stratigraphic variations in the new drill cores from Lake Titicaca represent at least five periods of glaciation in the tropical Andes. Diatom and geochemical analysis of piston cores from Lake Titicaca also indicated that wet climatic conditions prevailed during the most recent glaciation. However, the extent of glaciation in the tropics is highly constrained by mean monthly temperatures that are relatively constant throughout the year. Thus glaciers can only expand significantly when there is also a reduction in mean annual temperature. The most recent period of glaciation and the older glacial phases represented in the stratigraphy of the new drill cores were probably associated with both colder and wetter conditions than today. In contrast, the interglacials/interstadials were characterized by warmer and drier conditions, including significant drops in lake level.

Seltzer, G.; Baker, P.; Fritz, S.; Arnold, K.; Ballantine, A.; Tapia, P.; Veliz, C.

2001-12-01

101

First CSDP (Continental Scientific Drilling Program)/thermal regimes core hole project at Valles Caldera, New Mexico (VC-1): Drilling report  

SciTech Connect

This report is a review and summary of the core drilling operations of the first Valles Caldera research borehole (VC-1) under the Thermal Regimes element of the Continental Scientific Drilling Program (CSDP). The project is a portion of a broader program that seeks to answer fundamental scientific questions about magma, rock/water interactions, and volcanology through shallow (<1-km) core holes at Long Valley, California; Salton Sea, California; and the Valles Caldera, New Mexico. The report emphasizes coring operations with reference to the stratigraphy of the core hole, core quality description, core rig specifications, and performance. It is intended to guide future research on the core and in the borehole, as well as have applications to other areas and scientific problems in the Valles Caldera. The primary objectives of this Valles Caldera coring effort were (1) to study the hydrogeochemistry of a subsurface geothermal outflow zone of the caldera near the source of convective upflow, (2) to obtain structural and stratigraphic information from intracaldera rock formations in the southern ring-fracture zone, and (3) to obtain continuous core samples through the youngest volcanic unit in Valles Caldera, the Banco Bonito rhyolite (approximately 0.1 Ma). All objectives were met. The high percentage of core recovery and the excellent quality of the samples are especially notable. New field sample (core) handling and documentation procedures were successfully utilized. The procedures were designed to provide consistent field handling of the samples and logs obtained through the national CSDP.

Rowley, J.; Hawkins, W.; Gardner, J. (comps.)

1987-02-01

102

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

NASA Astrophysics Data System (ADS)

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

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

2011-12-01

103

Theoretical formulation of the core drilling method to evaluate stresses in concrete structures  

NASA Astrophysics Data System (ADS)

The hole drilling method is an ASTM Standard Test Method that is used to evaluate residual stresses in isotropic linearly elastic materials. In civil engineering, the method is often used to evaluate stresses in metal structures. However, the method is not applicable to concrete because the heterogeneous composition of concrete prevents strain measurements from being made over small gage lengths. This paper presents the theoretical formulation of a modified hole drilling method that is applicable to concrete structures. This modified method is referred to as the core drilling method. Potential applications of the method include the determination of insitu stress in a variety of reinforced concrete, prestressed concrete, and steel-concrete composite structures, including bridges, buildings, dams, retaining walls, tunnels, shafts, and containment vessels. Equations are derived to relate the displacements caused by local stress relaxation as a core hole is cut into a structure to the magnitudes and directions of the in situ stresses. Several practical stress states are treated in the formulation. Numerical examples are presented to verify the theoretical formulation and to further explain the method. .

Pessiki, Stephen; Turker, Hakan

2000-05-01

104

Quaternary paleoceanography of the central Arctic based on Integrated Ocean Drilling Program Arctic Coring Expedition 302 foraminiferal assemblages  

USGS Publications Warehouse

The Integrated Ocean Drilling Program (IODP) Arctic Coring Expedition (ACEX) Hole 4C from the Lomonosov Ridge in the central Arctic Ocean recovered a continuous 18 in record of Quaternary foraminifera yielding evidence for seasonally ice-free interglacials during the Matuyama, progressive development of large glacials during the mid-Pleistocene transition (MPT) ???1.2-0.9 Ma, and the onset of high-amplitude 100-ka orbital cycles ???500 ka. Foraminiferal preservation in sediments from the Arctic is influenced by primary (sea ice, organic input, and other environmental conditions) and secondary factors (syndepositional, long-term pore water dissolution). Taking these into account, the ACEX 4C record shows distinct maxima in agglutinated foraminiferal abundance corresponding to several interglacials and deglacials between marine isotope stages (MIS) 13-37, and although less precise dating is available for older sediments, these trends appear to continue through the Matuyama. The MPT is characterized by nearly barren intervals during major glacials (MIS 12, 16, and 22-24) and faunal turnover (MIS 12-24). Abundant calcareous planktonic (mainly Neogloboquadrina pachyderma sin.) and benthic foraminifers occur mainly in interglacial intervals during the Brunhes and very rarely in the Matuyama. A distinct faunal transition from calcareous to agglutinated foraminifers 200-300 ka in ACEX 4C is comparable to that found in Arctic sediments from the Lomonosov, Alpha, and Northwind ridges and the Morris Jesup Rise. Down-core disappearance of calcareous taxa is probably related to either reduced sea ice cover prior to the last few 100-ka cycles, pore water dissolution, or both. Copyright 2008 by the American Geophysical Union.

Cronin, T. M.; Smith, S. A.; Eynaud, F.; O'Regan, M.; King, J.

2008-01-01

105

The Chicxulub impact structure: What does the Yaxcopoil-1 drill core reveal?  

NASA Astrophysics Data System (ADS)

The Chicxulub impact structure, one of the largest impact structures on Earth, was formed 65 Ma by hypervelocity impact which led to the large mass-extinction at K-Pg boundary. This well preserved but buried structure has undergone numerous drillings and studies aimed to understand the formation mechanism, structure and age of the crater. The Yaxcopoil-1 (Yax-1) drill core, located in the southern sector of the Chicxulub crater, in the outer part of an annular trough, 62 km from the crater center, was drilled by ICDP in 2001-2002. Petrophysical, rock- and paleomagnetic studies of Yax-1 (Elbra and Pesonen, 2011) showed that physical properties characterize the various lithological units. Dependence on mineral composition rather than fabric was observed in pre-impact lithologies contrarily to the post-impact and impact rocks where the physical properties were dominated by porosity and reflected, in case of impactites, the impact formation mechanism with its numerous features resulting from melting, brecciation and fracturing. Furthermore, while the pre- and post-impact lithologies in Yax-1 are mostly dia- or paramagnetic, the impactite units indicated enhanced magnetizations and the presence of ferromagnetic, probably hydrothermally deposited magnetite and pyrrhotite. The sharp contrast of the impactites to the target and to post-impact lithologies allowed establishing the contact (especially the K-Pg boundary) between. The anisotropy, shape and orientation of the magnetic fraction illustrated the fabric randomization and showed the influence of impact-related redeposition and hydrothermal activity. The paleomagnetic data suggested that the Chicxulub impact occurred during the reverse polarity geomagnetic chron 29R, which is in agreement with the isotopic dates of the Chicxulub impact as well as with expected K-Pg boundary polarity. Reference Elbra, T. and Pesonen, L.J., 2011. Physical properties of the Yaxcopoil-1 deep drill core, Chicxulub impact structure, Mexico. Meteoritics & Planetary Science 46, 11, p. 1640-1652.

Elbra, T.

2013-05-01

106

Procedures for use of, and drill cores and cuttings available for study at, the Lithologic Core Storage Library, Idaho National Engineering Laboratory, Idaho  

SciTech Connect

In 1990, the US Geological Survey, in cooperation with the US Department of Energy, Idaho Operations Office, established the Lithologic Core Storage Library at the Idaho National Engineering Laboratory (INEL). The facility was established to consolidate, catalog, and permanently store nonradioactive drill cores and cuttings from investigations of the subsurface conducted at the INEL, and to provide a location for researchers to examine, sample, and test these materials. The facility is open by appointment to researchers for examination, sampling, and testing of cores and cuttings. This report describes the facility and cores and cuttings stored at the facility. Descriptions of cores and cuttings include the well names, well locations, and depth intervals available. Most cores and cuttings stored at the facility were drilled at or near the INEL, on the eastern Snake River Plain; however, two cores drilled on the western Snake River Plain are stored for comparative studies. Basalt, rhyolite, sedimentary interbeds, and surficial sediments compose the majority of cores and cuttings, most of which are continuous from land surface to their total depth. The deepest core stored at the facility was drilled to 5,000 feet below land surface. This report describes procedures and researchers` responsibilities for access to the facility, and examination, sampling, and return of materials.

Davis, L.C.; Hannula, S.R.; Bowers, B.

1997-03-01

107

Secondary mineralization and hydrothermal alteration in the Reydarfjordur drill core, eastern Iceland  

NASA Astrophysics Data System (ADS)

Deep crustal drilling in eastern Iceland has allowed study of a fossil hydrothermal system at a constructive plate margin. The drilled sequence consists of partly to completely altered subaerial lava flows, basaltic dikes, and minor clastic material. Alteration and secondary mineralization are most intense in the flow top breccias where water/rock ratios are presumed to have been the highest. In the upper portion of the cored sequence (to a depth of about 1200 m) alteration is characterized by the deposition of clay minerals ± calcite ± quartz ± laumontite into open spaces such as vugs and vesicles. Low-temperature zeolites, such as stilbite, epistilbite, mordenite, and heulandite, are also present but are restricted to the upper 500 m of the drill core. Below 1200 m, alteration is characterized by the dissolution and replacement of both primary minerals and earlier authigenic minerals, followed by partial filling of dissolution cavities. Early mineral assemblages consist of epidote ± quartz ± prehnite ± chlorite ± albite, and a later superimposed assemblage consists of calcite + laumontite ± anhydrite. Authigenic sphene, pyrite, chalcopyrite, pumpellyite, actinolite, and wairakite also occur sporadically in the cored sequence. Secondary mineral assemblages and temperature measurements of fluid inclusions suggest a maximum temperature of alteration of about 300°C. Fluid inclusion compositions indicate that the geothermal fluid was meteoric water with very low salinities and high calcium activities. Iron activities and oxygen fugacities were highest in the deeper portions of the systems. The mineral paragenesis suggests that the fluid composition, temperature, and PCO2 varied significantly with time. The thermal energy for the geothermal system was probably derived from a high-level magma chamber associated with nearby Thingmuli volcano. Local contact metamorphism, indicated by the formation of garnet, occurred during late stage emplacement of dikes into the lava pile. Chlorite ± calcite ± laumontite assemblages were also deposited along subvertical fractures at this time.

Mehegan, James M.; Robinson, Paul T.; Delaney, John R.

1982-08-01

108

Rare gases and Ca, Sr, and Ba in Apollo 17 drill-core fines  

NASA Technical Reports Server (NTRS)

Trapped gas isotopic compositions and spallation gas concentrations as functions of depth in the Apollo 17 drill core were determined from mass spectrometer studies by means of correlation techniques. The distribution of He, Ne, Ar, Kr, and Xe as well as Ca, Sr, and Ba was investigated, and rare-gas spallation and neutron capture profiles are compared with attention to proposed depositional models for the Taurus-Littrow regolith. The data exclude a sedimentation pattern similar to that found at the Apollo 15 site but are possibly compatible with long-term continuous accretion models or models of very recent rapid accumulation of regolith.

Pepin, R. O.; Dragon, J. C.; Johnson, N. L.; Bates, A.; Coscio, M. R., Jr.; Murthy, V. R.

1975-01-01

109

Characterization and depositional and evolutionary history of the Apollo 17 deep drill core  

NASA Technical Reports Server (NTRS)

With a depth resolution of about 0.5 cm, the stratigraphy of the approximately 3 m Apollo 17 deep drill core by measurement of the total FeO concentration is characterized along with the FMR surface exposure (maturity) index Is/FeO, the metallic iron concentration Fe-vsm, and the FMR linewidth delta-H. For stratigraphic characterization, the first two parameters are the most important. Most of the core is characterized by a FeO concentration of approximately 15.5 wt. %; there is a more mafic zone in the upper approximately 75 cm where the maximum FeO concentration is approximately 18.5 wt. %, and a more felsic zone between approximately 225 and 260 cm where the minimum FeO concentration is approximately 14.0%. As indicated by Is/FeO, most of the soil in the core is submature to mature; the only immature zone is located between approximately 20 and 60 cm and is one of the most distinctive features in the core. A two stage model for the depositional and evolutionary history of the Apollo 17 deep drill core is proposed: (1) deposition by one event approximately 110 m.y. ago or deposition by a sequence of closely spaced events initating a maximum of approximately 200 m.y. ago and terminating approximately 110 m.y. ago, (2) in situ reworking (gardening) to a depth of approximately 26 cm in the period between approximately 110 m.y. ago and the present day.

Morris, R. V.; Lauer, H. V., Jr.; Gose, W. A.

1979-01-01

110

Interrelating the breakage and composition of mined and drill core coal  

NASA Astrophysics Data System (ADS)

Particle size distribution of coal is important if the coal is to be beneficiated, or if a coal sales contract includes particle size specifications. An exploration bore core sample of coal ought to be reduced from its original cylindrical form to a particle size distribution and particle composition that reflects, insofar as possible, a process stream of raw coal it represents. Often, coal cores are reduced with a laboratory crushing machine, the product of which does not match the raw coal size distribution. This study proceeds from work in coal bore core reduction by Australian investigators. In this study, as differentiated from the Australian work, drop-shatter impact breakage followed by dry batch tumbling in steel cylinder rotated about its transverse axis are employed to characterize the core material in terms of first-order and zeroth-order breakage rate constants, which are indices of the propensity of the coal to degrade during excavation and handling. Initial drop-shatter and dry tumbling calibrations were done with synthetic cores composed of controlled low-strength concrete incorporating fly ash (as a partial substitute for Portland cement) in order to reduce material variables and conserve difficult-to-obtain coal cores. Cores of three different coalbeds--Illinois No. 6, Upper Freeport, and Pocahontas No. 5 were subjected to drop-shatter and dry batch tumbling tests to determine breakage response. First-order breakage, characterized by a first-order breakage index for each coal, occurred in the drop-shatter tests. First- and zeroth-order breakage occurred in dry batch tumbling; disappearance of coarse particles and creation of fine particles occurred in a systematic way that could be represented mathematically. Certain of the coal cores available for testing were dry and friable. Comparison of coal preparation plant feed with a crushed bore core and a bore core prepared by drop-shatter and tumbling (all from the same Illinois No.6 coal mining property) indicated that the size distribution and size fraction composition of the drop-shattered/tumbled core more closely resembled the plant feed than the crushed core. An attempt to determine breakage parameters (to allow use of selection and breakage functions and population balance models in the description of bore core size reduction) was initiated. Rank determination of the three coal types was done, indicating that higher rank associates with higher breakage propensity. The two step procedure of drop-shatter and dry batch tumbling simulates the first-order (volume breakage) and zeroth-order (abrasion of particle surfaces) that occur in excavation and handling operations, and is appropriate for drill core reduction prior to laboratory analysis.

Wilson, Terril Edward

111

Tecuamburro Volcano, Guatemala geothermal gradient core hole drilling, operations, and preliminary results  

SciTech Connect

A geothermal gradient core hole (TCB-1) was drilled to a depth of 700+ m at the Tecuamburro geothermal site, Guatemala during February and March, 1990. The core hole is located low on the northern flank of the Tecuamburro Volcano complex. Preliminary analysis of cores (>98% core recovery) indicates that the hydrothermal system may be centered in the 4-km-diameter Chupadero Crater, which has been proposed as the source of pyroxene pumice deposits in the Tecuamburro area. TCB-1 is located 300 m south of a 300-m-diameter phreatic crater, Laguna Ixpaco; the core hole penetrates the thin edge of a tuff ring surrounding Ixpaco and zones of hydrothermal brecciation within the upper 150 m may be related to the phreatic blast, dated at 2,910 {sup 14}C years. At the time of this writing, the unequilibrated temperature at a depth of 570m was 180{degree}C. Data on fracturing, permeability, hydrothermal alteration, and temperature will be presented. 3 refs., 3 figs.

Goff, S.; Heiken, G.; Goff, F.; Gardner, J. (Los Alamos National Lab., NM (USA)); Duffield, W. (Geological Survey, Flagstaff, AZ (USA)); Martinelli, L.; Aycinena, S. (Swissboring Overseas Corp. Ltd., Guatemala City (Guatemala)); Castaneda, O. (Unidad de Desarrollo Geotermico, Guatemala City (Guatemala). Inst. Nacional de Electrificacion)

1990-01-01

112

Physical properties of the drill core from the El'gygytgyn impact structure, NE Russia  

NASA Astrophysics Data System (ADS)

The El'gygytgyn impact structure in northeast Russia was drilled in 2008/2009. The 3.5 Ma old structure has a rim-to-rim diameter of 18 km and is the only known impact structure that has been formed on a siliceous volcanic target. The petrophysical, rock- and paleomagnetic properties, including attempted reorientation of samples, along the El'gygytgyn drill core were analyzed. Physical properties, such as bulk density, porosity, seismic velocity, and electrical conductivity, clearly showed the propagation of shock and the associated fracturing. The grain density, however, was probably influenced by the postimpact hydrothermal activity and/or the distribution of impact melt. The highest values of electrical conductivity coincided with higher concentrations of particular metals as indicated by Raschke et al. (2012a). The rock- and paleomagnetic investigations showed iron-titanium oxides with varying oxidation/reduction states as the main magnetic fraction in the core samples and indicated them as carriers for remanent magnetization. With few exceptions, most samples showed normal polarity of characteristic remanent magnetization and confirmed that the impact occurred after the Gauss/Gilbert (approximately 3.596 Ma) reversal. Shallower inclinations than that expected for a 3.5 Ma dipole field were probably due to impact-related block movements and/or compaction.

Maharaj, Dharmindar; Elbra, Tiiu; Pesonen, Lauri J.

2013-07-01

113

Evaluation of commercial drilling and geological software for deep drilling applications  

NASA Astrophysics Data System (ADS)

The avoidance of operational delays, financial losses and drilling hazards are key indicators for successful deep drilling operations. Real-time monitoring of drilling operation data as well as geological and petrophysical information obtained during drilling provide valuable knowledge that can be integrated into existing geological and mechanical models in order to improve the drilling performance. We have evaluated ten different geological and drilling software packages capable to integrate real-time drilling and planning data (e.g. torque, drag, well path, cementing, hydraulic data, casing design, well control, geo-steering, cost and time) as well as other scientific and technical data (i.e. from drilling core, geophysical downhole logging, production test) to build geological and geophysical models for planning of further deep drillings in a given geological environment. To reach this goal, the software has to be versatile to handle different data formats from disciplines such as geology, geophysics, petrophysics, seismology and drilling engineering as well as data from different drilling targets, such as geothermal fluids, oil/gas, water reservoirs, mining purpose, CO2 sequestration, or scientific goals. The software must be capable to analyze, evaluate and plan in real-time the next drilling steps in the best possible way and under safe conditions. A preliminary geological and geophysical model with the available data from site surveys and literature is built to address a first drilling plan, in which technical and scientific aspects are taken into consideration to perform the first drilling (wildcat well). During the drilling, the acquired scientific and technical data will be used to refine the previous geological-drilling model. The geological model hence becomes an interactive object strongly linked to the drilling procedure, and the software should allow to make rapid and informed decisions while drilling, to maximize productivity and minimize drilling risks and costs. This procedure enables a timely, efficient and accurate data access and exchange among the rig site data acquisition system, office-based software applications and data storage. The loading of real-time data has to be quick and efficient in order to refine the model and learn the lessons for the next drilling operations.

Pierdominici, Simona; Prevedel, Bernhard; Conze, Ronald; Tridec Team

2013-04-01

114

Mineralogical and petrological investigations of rocks cored from depths higher than 440m during the CFDDP drilling activities at the Campi Flegrei caldera (southern Italy).  

NASA Astrophysics Data System (ADS)

The Campi Flegrei caldera is one of the highest-risk volcanic areas on the Earth and the drilling exploiting activities carried by the Azienda Geologica Italiana Petroli (AGIP) and the Società Anonima Forze Endogene Napoletane (SAFEN) since the '40 have produced the main constrains to the definition of the subsurface structure of the caldera. The eastern part of the caldera represents among the least known in the area in terms of both volcanic and geothermal evolution. Recently, in the 2012, the Campi Flegrei Deep Drilling Project (CFDDP) allowed performing a 506m hole in this sector of the caldera, i.e. in the Bagnoli Plain, where the western districts of the Neapolitan city developed. Here, we present the preliminary results from mineralogical, geochemical and petrological investigations of drilling core samples collected at -443 m and -506 m of depths. Scanning electron microscopy (SEM), microanalysis by energy dispersive spectroscopy (EDS) together with investigations by back-scattered electron mode (SEM-BSE), and powder X-Ray diffraction (XRD) allowed: 1) defining the primary sample lithology; 2) examining the features of both primary and secondary minerals; 3) describing the relationships among texture and secondary mineralization. Sr isotope analyses were furthermore performed on separated feldspars. Density measurements were also carried out on the bottom core. The investigated samples are representative of strongly altered, massive pyroclastic tuffs, which made of a chaotic ashy to sandy matrix including low crystalline juvenile scoria and pumice fragments. Textural features of secondary mineralization are consistent with circulation of hydrothermal fluids as the results of a wide geothermal resource in the caldera. Comparing the paleo-temperature inferred by authigenic minerals occurrence and the temperature measured at the bottom hole (~60°C) during geophysical logs, we suggest the cooling of the hydrothermal system in the eastern sector of the caldera.

Mormone, Angela; Piochi, Monica; Balassone, Giuseppina; Carlino, Stefano; Somma, Renato; Troise, Claudia; De Natale, Giuseppe

2014-05-01

115

Visible-Near Infrared Point Spectrometry of Drill Core Samples from Río Tinto, Spain: Results from the 2005 Mars Astrobiology Research and Technology Experiment (MARTE) Drilling Exercise  

NASA Astrophysics Data System (ADS)

Sampling of subsurface rock may be required to detect evidence of past biological activity on Mars. The Mars Astrobiology Research and Technology Experiment (MARTE) utilized the Río Tinto region, Spain, as a Mars analog site to test dry drilling technologies specific to Mars that retrieve subsurface rock for biological analysis. This work examines the usefulness of visible-near infrared (VNIR) (450-1000 nm) point spectrometry to characterize ferric iron minerals in core material retrieved during a simulated Mars drilling mission. VNIR spectrometry can indicate the presence of aqueously precipitated ferric iron minerals and, thus, determine whether biological analysis of retrieved rock is warranted. Core spectra obtained during the mission with T1 (893-897 nm) and T2 (644-652 nm) features indicate goethite-dominated samples, while relatively lower wavelength T1 (832-880 nm) features indicate hematite. Hematite/goethite molar ratios varied from 0 to 1.4, and within the 880-898 nm range, T1 features were used to estimate hematite/goethite molar ratios. Post-mission X-ray analysis detected phyllosilicates, which indicates that examining beyond the VNIR (e.g., shortwave infrared, 1000-2500 nm) will enhance the detection of other minerals formed by aqueous processes. Despite the limited spectral range of VNIR point spectrometry utilized in the MARTE Mars drilling simulation project, ferric iron minerals could be identified in retrieved core material, and their distribution served to direct core subsampling for biological analysis.

Sutter, Brad; Brown, Adrian J.; Stoker, Carol R.

2008-10-01

116

High permafrost ice contents in Holocene slope deposits as observed from shallow geophysics and a coring program in Pangnirtung, Nunavut, Canada  

NASA Astrophysics Data System (ADS)

A study of permafrost conditions was undertaken in the Hamlet of Pangnirtung, Nunavut, by the Geological Survey of Canada (GSC) and Université Laval's Centre d'études nordiques (CEN) to support decision makers in their community planning work. The methods used for this project were based on geophysical and geomorphological approaches, including permafrost cores drilled in surficial deposits and ground penetrating radar surveys using a GPR Pulse EKKO 100 extending to the complete community area and to its projected expansion sector. Laboratory analysis allowed a detailed characterization of permafrost in terms of water contents, salinity and grain size. Cryostratigraphic analysis was done via CT-Scan imagery of frozen cores using medical imaging softwares such as Osiris. This non destructive method allows a 3D imaging of the entire core in order to locate the amount of the excess ice, determine the volumetric ice content and also interpret the ice-formation processes that took place during freezing of the permafrost. Our new map of the permafrost conditions in Pangnirtung illustrates that the dominant mapping unit consist of ice-rich colluvial deposits. Aggradationnal ice formed syngenitically with slope sedimentation. Buried soils were found imbedded in this colluvial layer and demonstrates that colluviation associated with overland-flow during snowmelt occurred almost continuously since 7080 cal. BP. In the eastern sector of town, the 1 to 4 meters thick colluviums cover till and a network of ice wedges that were revealed as spaced hyperbolic reflectors on GPR profiles. The colluviums also cover ice-rich marine silt and bedrock in the western sector of the hamlet; marine shells found in a permafrost core yielded a radiocarbon date of 9553 cal. BP which provides a revised age for the local deglaciation and also a revised marine submergence limit. Among the applied methods, shallow drilling in coarse grained permafrost, core recovery and CT-Scan allowed the discovery of the importance of Holocene slope processes on shaping the surface of the terrain and leading to the observed cryostructures and ice contents in the near surface permafrost.

Carbonneau, A.; Allard, M.; L'Hérault, E.; LeBlanc, A.

2011-12-01

117

Petrophysical Properties of Twenty Drill Cores from the Los Azufres, Mexico, Geothermal Field  

SciTech Connect

For this study we selected 20 drill cores covering a wide range of depths (400-3000 m), from 15 wells, that provide a reasonable coverage of the field. Only andesite, the largely predominant rock type in the field, was included in this sample. We measured bulk density, grain (solids) density, effective porosity and (matrix) permeability on a considerable number of specimens taken from the cores; and inferred the corresponding total porosity and fraction of interconnected total porosity. We characterized the statistical distributions of the measured and inferred variables. The distributions of bulk density and grain density resulted approximately normal; the distributions of effective porosity, total porosity and fraction of total porosity turned out to be bimodal; the permeability distribution resulted highly skewed towards very small (1 mdarcy) values, though values as high as 400 mdarcies were measured. We also characterized the internal inhomogeneity of the cores by means of the ratio (standard deviation/mean) corresponding to the bulk density in each core (in average there are 9 specimens per core). The cores were found to present clearly discernible inhomogeneity; this quantitative characterization will help design new experimental work and interpret currently available and forthcoming results. We also found statistically significant linear correlations between total density and density of solids, effective porosity and total density, total porosity and total density, fraction of interconnected total porosity and the inverse of the effective porosity, total porosity and effective porosity; bulk density and total porosity also correlate with elevation. These results provide the first sizable and statistically detailed database available on petrophysical properties of the Los Azufres andesites. 1 tab., 16 figs., 4 refs.

Iglesias, E.R.; Contreras L., E.; Garcia G., A.; Dominquez A., Bernardo

1987-01-20

118

HSDP II Drill Core: Preliminary Rock Strength Results and Implications to Flank Stability, Mauna Kea Volcano  

NASA Astrophysics Data System (ADS)

Selected portions of the 3-km HSDP II core were tested to provide unconfined rock strength data from hyaloclastite alteration zones and pillow lavas. Though the drilling project was not originally intended for strength purpose, it is believed the core can provide unique rock strength insights into the flank stability of the Hawaiian Islands. The testing showed that very weak rock exists in the hyaloclastite abundant zones in the lower 2-km of the core with strength dependent on the degree of consolidation and type of alteration. Walton and Schiffman identified three zones of alteration, an upper incipient alteration zone (1080-1335m), a smectitic zone (1405-1573m) and a lower palagonitic zone from about 1573 m to the base of the core. These three zones were sampled and tested together with pillow lava horizons for comparison. Traditional cylindrical core was not available as a consequence of the entire core having been split lengthwise for archival purposes. Hence, point load strength testing was utilized which provides the unconfined compressive strength on irregular shaped samples. The lowest unconfined strengths were recorded from incipient alteration zones with a mean value of 9.5 MPa. Smectitic alteration zones yielded mean values of 16.4 MPa, with the highest measured alteration strengths from the palagonite zones with a mean value of 32.1 MPa. As anticipated, the highest strengths were from essentially unaltered lavas with a mean value of 173 MPa. Strength variations of between one to two orders of magnitude were identified in comparing the submarine hyaloclastite with the intercalated submarine lavas. The weakest zones within the hyaloclastites may provide horizons for assisting flank collapse by serving as potential thrust zones and landslide surfaces.

Thompson, N.; Watters, R. J.; Schiffman, P.

2004-12-01

119

Physical properties of the Yaxcopoil-1 deep drill core, Chicxulub impact structure, Mexico  

NASA Astrophysics Data System (ADS)

The Chicxulub structure in Mexico, one of the largest impact structures on Earth, was formed 65 Ma by a hypervelocity impact that led to the large mass extinction at the K-Pg boundary. The Chicxulub impact structure is well preserved, but is buried beneath a sequence of carbonate sediments and, thus, requires drilling to obtain subsurface information. The Chicxulub Scientific Drilling Program was carried out at Hacienda Yaxcopoil in the framework of the International Continental Scientific Drilling Program in 2001-2002. The structure was cored from 404 m down to 1511 m, through three intervals: 794 m of postimpact Tertiary sediments, a 100 m thick impactite sequence, and 616 m of preimpact Cretaceous rocks thought to represent a suite of megablocks. Physical property investigations show that the various lithologies, including the impactite units and the K-Pg boundary layer, can be characterized by their physical properties, which depend on either changes in fabric or on mineralogical variations. The magnetic properties show mostly dia- or paramagnetic behavior, with the exception of the impactite units that indicate the presence of ferromagnetic, probably hydrothermally deposited magnetite and pyrrhotite. The magnetic fraction contributes mainly to enhanced magnetization in the impactite lithologies and, in this way, to the observed magnetic anomalies. The shape and orientation of the magnetic grains are varied and reflect inhomogeneous fabric development and the influence of impact-related redeposition and hydrothermal activity. The Chicxulub impact occurred at the time of the reverse polarity geomagnetic chron 29R, and this finding is consistent with the age of the K-Pg boundary.

Elbra, Tiiu; Pesonen, Lauri J.

2011-11-01

120

Drilling, Coring and Sampling Using Piezoelectric Actuated Mechanisms: From the USDC to a Piezo-Rotary-Hammer Drill  

NASA Technical Reports Server (NTRS)

NASA exploration missions are increasingly including sampling tasks but with the growth in engineering experience (particularly, Phoenix Scout and MSL) it is now very much recognized that planetary drilling poses many challenges. The difficulties grow significantly with the hardness of sampled material, the depth of drilling and the harshness of the environmental conditions. To address the requirements for samplers that could be operated at the conditions of the various bodies in the solar system, a number of piezoelectric actuated drills and corers were developed by the Advanced Technologies Group of JPL. The basic configuration that was conceived in 1998 is known as the Ultrasonic/Sonic Driller/Corer (USDC), and it operates as a percussive mechanism. This drill requires as low preload as 10N (important for operation at low gravity) allowing to operate with as low-mass device as 400g, use an average power as low as 2- 3W and drill rocks as hard as basalt. A key feature of this drilling mechanism is the use of a free-mass to convert the ultrasonic vibrations generated by piezoelectric stack to sonic impacts on the bit. Using the versatile capabilities f the USDC led to the development of many configurations and device sizes. Significant improvement of the penetration rate was achieved by augmenting the hammering action by rotation and use of a fluted bit to remove cuttings. To reach meters deep in ice a wireline drill was developed called the Ultrasonic/Sonic Gopher and it was demonstrated in 2005 to penetrate about 2-m deep at Antarctica. Jointly with Honeybee Robotics, this mechanism is currently being modified to incorporate rotation and inchworm operation forming Auto-Gopher to reach meters deep in rocks. To take advantage of the ability of piezoelectric actuators to operate over a wide temperatures range, piezoelectric actuated drills were developed and demonstrated to operate at as cold as -200oC and as hot as 500oC. In this paper, the developed mechanisms will be reviewed and discussed including the configurations, capabilities, and challenges.

Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea; Bao, Xiaoqi

2012-01-01

121

Paleomagnetic records from carbonate legs in the Southern Oceans and attendant drilling and coring related effects  

NASA Astrophysics Data System (ADS)

Ocean Drilling Program (ODP) Leg 182, to the Great Australian Bight (GAB), Leg 189 around Tasmania, and Leg 194 off the Great Barrier Reef on the Marion Plateau, all sampled thick carbonate sections that tested the coring techniques and the magnetics instrumentation on the JOIDES Resolution. Coring overprints were demonstrated due to: (1) sediment deformation during initial penetration of the advanced piston corer, (2) disturbance by core "suck in" during recovery, (3) the magnetic fields of the bottom hole assembly, (4) magnetic contamination of core liners, and (5) core splitting and storage. All of these effects can cause problems in determining the magnetostratigraphy of carbonates. The principal highlights of the magnetostratigraphy of these three ODP legs were as follows. (1) The discovery during Leg 182 of an extended Brunhes section of carbonates in the GAB that was hundreds of meters thick. (2) Documentation in Hole 1172 of Leg 189 of the timing of the Eocene-Oligocene transition from the "Greenhouse" to "Icehouse" state and the rapid deepening of the Tasmanian Gateway. (3) Recovery of a complete magnetostratigraphy from Plio-Pleistocene carbonates with a sedimentation rate of some 20 m/Ma and the discovery of a small hiatus including the top of the Matuyama (C1r) and the Jaramillo (C1r.1n). (4) The documentation of a chronology from Sites 1193, 1194, and 1195 of Leg 194 gave ages for the critical sequence boundary at each site consistent with biostratigraphy that was used to evaluate the late middle Miocene eustatic sea level fall.

Fuller, M.; Molina-Garza, R.; Touchard, Y.; Kidane, T.

2006-07-01

122

Very low Ti /VLT/ basalts - A new mare rock type from the Apollo 17 drill core  

NASA Technical Reports Server (NTRS)

Phaneritic fragments, vitrophyres, and glass beads of a new very low Ti (VLT) mare basalt are found in the Apollo 17 drill core. VLT lithic fragments are characterized by TiO2 content of approximately 0.5%, Mg/(Mg + Fe) of approximately 0.52, CaO/Al2O3 of approximately 0.9, and low alkali content. Although mineral systematics and modal composition of VLT basalt are similar to Apollo 12 and 15 low Ti basalts, VLT basalts cannot be related to these mare basalts by crystal fractionation. Since VLT basalt is isochemical with some of the less mafic green glasses, fractionation of VLT magma from a liquid of green-glass composition is a possibility. Spectral reflectance studies suggest that VLT-type basalts may be relatively common in mare basins.

Vaniman, D. T.; Papike, J. J.

1977-01-01

123

Petrography of shock features in the 1953 Manson 2-A drill core  

NASA Technical Reports Server (NTRS)

Drilling of Nx core in late 1953 into an anomalous zone of disturbed rocks northwest of Manson, Iowa disclosed presence of extensive breccias including crystalline rocks brought to the surface from depths of 4 km or more. Hole 2-A penetrated breccias dominated by leucocratic igneous and metamorphic lithologies, later interpreted to be part of a general ringed peak complex within a 35 km wide impact structure produced about 65 Ma ago. Proof of this origin was given in 1966 by NMS through recognition of shock metamorphic features in 2-A materials during a cursory examination of samples provided by R.A. Hoppin, University of Iowa. A detailed study of this material now underway has revealed that most breccia clasts in 2-A show abundant and varied evidence of shock damage, including extensive planar deformation features (PDF) in quartz, K-feldspar, plagioclase, and a pyroxene and varying degrees of isotropization and incipient melting in feldspars.

Short, N. M.; Gold, D. P.

1993-01-01

124

U.S. geological survey core drilling on the Atlantic shelf  

USGS Publications Warehouse

The first broad program of scientific shallow drilling on the U.S. Atlantic continental shelf has delineated rocks of Pleistocene to Late Cretaceous age, including phosphoritic Miocene strata, widespread Eocene carbonate deposits that serve as reflective seismic markers, and several regional unconformities. Two sites, off Maryland and New Jersey, showed light hydrocarbon gases having affinity to mature petroleum. Pore fluid studies showed that relatively fresh to brackish water occurs beneath much of the Atlantic continental shelf, whereas increases in salinity off Georgia and beneath the Florida-Hatteras slope suggest buried evaporitic strata. The sediment cores showed engineering properties that range from good foundation strength to a potential for severe loss of strength through interaction between sediments and manmade structures. Copyright ?? 1979 AAAS.

Hathaway, J. C.; Poag, C. W.; Valentine, P. C.; Miller, R. E.; Schultz, D. M.; Manheim, F. T.; Kohout, F. A.; Bothner, M. H.; Sangrey, D. A.

1979-01-01

125

Petrology and geochemistry of lithic fragments separated from the Apollo 15 deep-drill core  

NASA Technical Reports Server (NTRS)

Petrological and geochemical analysis of lithic fragments separated from the Apollo 15 deep-drill core showed these fragments to fall into the essentially the same range of rock types as observed in surface soil samples and large rock samples. Three particles are singled out as being of special interest. One sample is a mare basalt containing extremely evolved phases. The particle may represent small-scale imperfect crystal/liquid separation in a lava flow. A green glass particle is not the ultramafic emerald green glass described from the Apollo 15 site, but rather an ANT-like light green color, and has a quite different chemical composition from the ultramafic variety. One mare basalt displays a positive Eu anomaly and is enriched in plagioclase relative to olivine plus pyroxene.

Lindstrom, M. M.; Nielsen, R. L.; Drake, M. J.

1977-01-01

126

Characterization of tuyere-level core-drill coke samples from blast furnace operation  

SciTech Connect

A suite of tuyere-level coke samples have been withdrawn from a working blast furnace during coal injection, using the core-drilling technique. The samples have been characterized by size exclusion chromatography (SEC), Fourier transform Raman spectroscopy (FT-RS), and X-ray powder diffraction (XRD) spectroscopy. The 1-methyl-2-pyrrolidinone (NMP) extracts of the cokes sampled from the 'bosh', the rear of the 'bird's nest', and the 'dead man' zones were found by SEC to contain heavy soot-like materials (ca. 10{sup 7}-10{sup 8} apparent mass units). In contrast, NMP extracts of cokes taken from the raceway and the front of the 'bird's nest' only contained a small amount of material of relatively lower apparent molecular mass (up to ca. 10{sup 5} u). Since the feed coke contained no materials extractable by the present method, the soot-like materials are thought to have formed during the reactions of volatile matter released from the injectant coal, probably via dehydrogenation and repolymerization of the tars. The Raman spectra of the NMP-extracted core-drilled coke samples showed variations reflecting their temperature histories. Area ratios of D-band to G-band decreased as the exposure temperature increased, while intensity ratios of D to G band and those of 2D to G bands increased with temperature. The graphitic (G), defect (D), and random (R) fractions of the carbon structure of the cokes were also derived from the Raman spectra. The R fractions decreased with increasing temperature, whereas G fractions increased, while the D fractions showed a more complex variation with temperature. These data appear to give clues regarding the graphitization mechanism of tuyere-level cokes in the blast furnace. 41 refs., 9 figs., 6 tabs.

S. Dong; N. Paterson; S.G. Kazarian; D.R. Dugwell; R. Kandiyoti [Imperial College London, London (United Kingdom). Department of Chemical Engineering

2007-12-15

127

Nondestructive continuous physical property measurements of core samples recovered from hole B, Taiwan Chelungpu-Fault Drilling Project  

Microsoft Academic Search

The Taiwan Chelungpu-Fault Drilling Project was undertaken in 2002 to investigate the faulting mechanism of the 1999 Mw 7.6 Taiwan Chi-Chi earthquake. Hole B penetrated the Chelungpu fault, and core samples were recovered from between 948.42- and 1352.60-m depth. Three major zones, designated FZB1136 (fault zone at 1136-m depth in hole B), FZB1194, and FZB1243, were recognized in the core

Tetsuro Hirono; En-Chao Yeh; Weiren Lin; Hiroki Sone; Toshiaki Mishima; Wonn Soh; Yoshitaka Hashimoto; Osamu Matsubayashi; Kan Aoike; Hisao Ito; Masataka Kinoshita; Masafumi Murayama; Sheng-Rong Song; Kuo-Fong Ma; Jih-Hao Hung; Chien-Ying Wang; Yi-Ben Tsai; Tomomi Kondo; Masahiro Nishimura; Soichi Moriya; Tomoyuki Tanaka; Toru Fujiki; Lena Maeda; Hiroaki Muraki; Toshikatsu Kuramoto; Kazuhiro Sugiyama; Toshikatsu Sugawara

2007-01-01

128

Application of borehole geophysics to fracture identification and characterization in low porosity limestones and dolostones  

SciTech Connect

Geophysical logging was conducted in exploratory core holes drilled for geohydrological investigations at three sites used for waste disposal on the US Department of Energy's Oak Ridge Reservation. Geophysical log response was calibrated to borehole geology using the drill core. Subsequently, the logs were used to identify fractures and fractured zones and to characterize the hydrologic activity of such zones. Results of the study were used to identify zones of ground water movement and to select targets for subsequent piezometer and monitoring well installation. Neutron porosity, long- and short-normal resistivity, and density logs exhibit anomalies only adjacent to pervasively fractured zones and rarely exhibit anomalies adjacent to individual fractures, suggesting that such logs have insufficient resolution to detect individual fractures. Spontaneous potential, single point resistance, acoustic velocity, and acoustic variable density logs, however, typically exhibit anomalies adjacent to both individual fractures and fracture zones. Correlation is excellent between fracture density logs prepared from the examination of drill core and fractures identified by the analysis of a suite of geophysical logs that have differing spatial resolution characteristics. Results of the study demonstrate the importance of (1) calibrating geophysical log response to drill core from a site, and (2) running a comprehensive suite of geophysical logs that can evaluate both large- and small-scale rock features. Once geophysical log responses to site-specific geological features have been established, logs provide a means of identifying fracture zones and discriminating between hydrologically active and inactive fracture zones. 9 figs.

Haase, C.S.; King, H.L.

1986-01-01

129

Biostratigraphic Analysis of Core Samples from Wells Drilled in the Devonian Shale Interval of the Appalachian and Illinois Basins.  

National Technical Information Service (NTIS)

A palynological investigation was performed on 55 samples of core material from four wells drilled in the Devonian Shale interval of the Appalachian and Illinois Basins. Using a combination of spores and acritarchs, it was possible to divide the Middle De...

S. J. Martin R. E. Zielinski

1978-01-01

130

Structure and stress state of Hawaiian island basalts penetrated by the Hawaii Scientific Drilling Project deep core hole  

NASA Astrophysics Data System (ADS)

As part of the Hawaii Scientific Drilling Project (HSDP), an exploratory hole was drilled in 1993 to a depth of 1056 meters below sea level (mbsl) and a deeper hole was drilled to 3098 mbsl in 1999. A set of geophysical well logs was obtained in the deeper hole that provides fundamental information regarding the structure and the state of stress that exist within a volcanic shield. The acoustic televiewer generates digital, magnetically oriented images of the borehole wall, and inspection of this log yields a continuous record of fracture orientation with depth and also with age to 540 ka. The data depict a clockwise rotation in fracture strike through the surficial Mauna Loa basalts that settles to a constant heading in the underlying Mauna Kea rocks. This behavior reflects the depositional slope directions of lavas and the locations of volcanic sources relative to the drill site. The deviation log delineates the trajectory of the well bore in three-dimensional space. This path closely follows changes in fracture orientation with depth as the drill bit is generally prodded perpendicular to fracture strike during the drilling process. Stress-induced breakouts observed in the televiewer log identify the orientations of the maximum and minimum horizontal principal stresses to be north-south and east-west, respectively. This stress state is attributed to the combination of a sharp break in onshore-offshore slope that reduces stress east-west and the emergence of Kilauea that increases stress north-south. Breakouts are extensive and appear over approximately 30% of the open hole.

Morin, Roger H.; Wilkens, Roy H.

2005-07-01

131

The ICDP Dead Sea deep drill cores: records of climate change and tectonics in the Levant  

NASA Astrophysics Data System (ADS)

The Dead Sea drainage basin sits at the boundary of the Mediterranean and the Saharan climate zones, and the basin is formed by the Dead Sea transform fault. The ICDP-funded Dead Sea Deep Drilling Project recovered the longest and most complete paleo-environmental and paleo-seismic record in the Middle East, drilling holes of ~450 and ~350 meters in deep (~300 m below the lake level) and shallow sites (~3 m), respectively, and. The sediments record the evolving environmental conditions (e.g. droughts, rains, floods, dust-storms), as well as tectonics (earthquake layers). The core can be dated using 14C on organic materials, U-Th on inorganic aragonite, stable isotopes, and layer counting. They were opened, described, and XRF-scanned during June to November 2011, the first sampling party took place in July 2012, and study is now underway. Some important conclusions can already be drawn. The stratigraphy reflects the climate conditions. During wet climate intervals the lithology is typically varve-like laminated aragonite and detritus (aad), reflecting summer and winter seasons, respectively, and sequences of mud. Gypsum layers reflect more arid climate, and salt (halite) indicates extreme aridity. The Dead Sea expands during glacials, and the portion of the core that corresponds to the last glacial Lisan Formation above the shoreline is easily recognized in the core based on the common lithological sequence, and this allows us to infer a broad scale age model. Interglacials show all the lithologic facies (aad, mud, gypsum, salt), reflecting extreme climate variability, while glacials contain the aad, mud, and gypsum but lack salt layers. Thus we estimate that the deep site hole extends into MIS 7 (to ~200,000 years). Thin (up to several cm thick) seismic layers occur throughout the core, but thick (up to several meters) landslide deposits only occur during glacial intervals. The most dramatic discovery is evidence of an extreme dry interval during MIS 5 at the deep site. There is a ~40 cm thick interval of partly rounded pebbles in the core at ~235 m below the lake floor. It is the only clean pebbly unit in the core, and resembles a beach deposit. Below the layer there is ~45 meters of mainly salt. These observations indicate a severe dry interval during MIS 5. This observation has implications for the Middle East today, where the Dead Sea level is dropping at rates >1m/year, as all the countries in the area are using all the runoff. GCM models indicate a more arid future in the region. The core shows that the runoff nearly stopped during the last interglacial without human intervention. Dating is underway to constrain the timing of the extreme drydown.

Goldstein, S. L.; Stein, M.; Ben-Avraham, Z.; Agnon, A.; Ariztegui, D.; Brauer, A.; Haug, G. H.; Ito, E.; Kitagawa, H.; Torfstein, A.

2012-12-01

132

Workshop on core and sample curation for the National Continental Scientific Drilling Program  

SciTech Connect

The Workshop on Core and Sample Curation was held to discuss the best means of handling, distributing, and advertising samples and data collected during a Continental Scientific Drilling Program (CSDP) and to establish better communication between sample curators regarding common problems. It was geneerally agreed that CSDP samples should be handled, on a regional basis, by existing data systems and sample repositories judged to have adequate staff and support. Repository design, sample handling procedures, and sample accounting systems were discussed. Across North America, support for curation of geological samples was varied, but it was strongest within states or regions with well-established energy and mineral industries. A well-supported repository pays for itself through the circulation and preservation of samples and stratigraphic information. A national CSDP must have a well-established curatorial policy and system of regional repositories to circulate information and samples throughout the scientific community. Well-curated samples and data are a national resource with considerable benefits for industry and academia. Attendees agreed to form a Society of Geoscience Curators to maintain communication between curators from private, government, and university repositories and core research laboratories.

Goff, S.; Heiken, G. (eds.)

1981-05-06

133

Analysis of hydrologic structures within Mauna Kea volcano using diamond wireline core drilling  

NASA Astrophysics Data System (ADS)

The Humu'ula Groundwater Research Project was undertaken on the Island of Hawaii in an effort to characterize the hydrologic structures controlling groundwater movement and storage within the dry (~430 mm/year annual rainfall) saddle region between Mauna Loa and Mauna Kea volcanoes. The project drilled a 1764 m, continuously-cored, borehole from an elevation of 1946 m amsl. The shallow stratigraphy consisted of alluvial outwash of clastic debris, of both volcanic and glacial origin, from the upper slopes of Mauna Kea, and was underlain by highly permeable post-shield lavas to depths of a few hundred meters. Below this depth, shield stage lavas were dominated by highly-fractured and permeable pahoehoe lavas and (less common) a'a flows and occasional soil and ash accumulations at flow boundaries. As depths increased below 1000 m, progressive compaction of fragmental material was found at the flow boundaries and, by depths of ~1500 m, much of the void space in the flow boundaries had been collapsed and compacted. Increasing secondary mineralization was observed below about 1000 m depth that was exacerbated by rising temperatures and temperature gradients toward the bottom of the hole. Hydrologic conditions were strikingly different from those predicted by conventional models for ocean islands: the formation was dry down to only ~150 m where the first, thin, perched aquifer was encountered; a second, more substantial, perched aquifer was reached at only ~220 m depth that extended to ~360 m where a sequence of (remarkably thin) perching formations were recovered in the core down to about 420 m where unsaturated rocks were again encountered. Saturated conditions resumed at 550 m depth that continued to the total depth drilled; this latter zone is inferred to be the basal aquifer for Mauna Kea within this region of the island. Our initial analysis of the core suggests that thin, clay-rich, perching formations in the shallow stratigraphic column play a much larger role in groundwater transport than has generally been recognized; in the deeper interior of the volcano, compaction of flow boundaries (the major water carriers in the shallow stratigraphy) leads to a progressive decrease in permeability and reduction in the transport rates of recharge toward the shoreline aquifers.

Thomas, D. M.; Haskins, E.

2013-12-01

134

Subsurface Organics in Aseptic Cores From the MARTE Robotic Drilling Experiment: Ground truth and Contamination Issues  

NASA Astrophysics Data System (ADS)

The subsurface is the key environment for searching for life on planets lacking surface life. This includes the search for past/present life on Mars where possible subsurface life could exist [1]. The Mars-Analog-Rio-Tinto-Experiment (MARTE) performed a simulation of a Mars robotic drilling at the RT Borehole#7 Site ~6.07m, atop a massive-pyrite deposit from the Iberian Pyritic Belt. The RT site is considered an important analog of Sinus Meridiani on Mars, an ideal model analog for a subsurface Martian setting [2], and a relevant example of deep subsurface microbial community including aerobic and anaerobic chemoautotrophs [4-5]. Searching for microbes or bulk organics of biological origin in a subsurface sample from a planet is a key scientific objective of Robotic drilling missions. During the 2005 Field experiment 28 minicores were robotically handled and subsampled for life detection experiments under anti-contamination protocols. Ground truth included visual observation of cores and lab based Elemental and Isotope Ratios Mass Spectrometry analysis (EA-IRMS) of bulk organics in Hematite and Gohetite-rich gossanized tuffs, gossan and clay layers within 0-6m-depth. C-org and N-tot vary up to four orders of magnitude among the litter (~11Wt%, 0-1cm) and the mineralized (~3Wt%, 1-3cm) layers, and the first 6 m-depth (C-org=0.02-0.38Wt%). Overall, the distribution/ preservation of plant and soil-derived organics (d13C-org = 26 per mil to 24 per mil) is ten times higher (C-org=0.33Wt%) that in hematite-poor clays, or where rootlets are present, than in hematite- rich samples (C-org=<0.01Wt%). This is consistent with ATP assay (Lightning-MVP, Biocontrol) for total biomass in subsurface (Borehole#7 ~6.07m, ~avg. 153RLU) vs. surface soil samples (~1,500-81,449RLU) [5]. However, the in-situ ATP assay failed in detecting presence of roots during the in-situ life detection experiment. Furthermore, cm-sized roots were overlooked during remote observations. Finally, ATP Luminometry provided insights for potential contamination from core-handling and environmental dust loadings on cleaned/sterilized control surfaces (e.g., 6,782-36,243RLU/cm2). Cleanliness/sterility can be maintained by applying a simple sterile protocol under field conditions. Science results from this research will support future Astrobiology driven drilling mission planned on Mars. Specifically, ground truth offers relevant insights to assess strengths and limits of in-situ/remote observations vs. laboratory measurements. Results from this experiment will also aid the debate on advantages/ disadvantages of manned vs. robotic drilling missions on Mars or other planets. [1] Boston et al., 1997; [2] http://marte.arc.nasa.gov; [3] Stoker, C., et al., 2006 AbSciCon, [4] Stoker et al., submitted; [5] Bonaccorsi., et al., 2006 AbSciCon.

Bonaccorsi, R.; Stoker, C. R.

2006-12-01

135

Faulting processes in active faults - Evidences from TCDP and SAFOD drill core samples  

NASA Astrophysics Data System (ADS)

The microstructures, mineralogy and chemistry of representative samples collected from the cores of the San Andreas Fault drill hole (SAFOD) and the Taiwan Chelungpu-Fault Drilling project (TCDP) have been studied using optical microscopy, TEM, SEM, XRD and XRF analyses. SAFOD samples provide a transect across undeformed host rock, the fault damage zone and currently active deforming zones of the San Andreas Fault. TCDP samples are retrieved from the principal slip zone (PSZ) and from the surrounding damage zone of the Chelungpu Fault. Substantial differences exist in the clay mineralogy of SAFOD and TCDP fault gouge samples. Amorphous material has been observed in SAFOD as well as TCDP samples. In line with previous publications, we propose that melt, observed in TCDP black gouge samples, was produced by seismic slip (melt origin) whereas amorphous material in SAFOD samples was formed by comminution of grains (crush origin) rather than by melting. Dauphiné twins in quartz grains of SAFOD and TCDP samples may indicate high seismic stress. The differences in the crystallographic preferred orientation of calcite between SAFOD and TCDP samples are significant. Microstructures resulting from dissolution-precipitation processes were observed in both faults but are more frequently found in SAFOD samples than in TCDP fault rocks. As already described for many other fault zones clay-gouge fabrics are quite weak in SAFOD and TCDP samples. Clay-clast aggregates (CCAs), proposed to indicate frictional heating and thermal pressurization, occur in material taken from the PSZ of the Chelungpu Fault, as well as within and outside of the SAFOD deforming zones, indicating that these microstructures were formed over a wide range of slip rates.

Janssen, C.; Wirth, R.; Wenk, H.-R.; Morales, L.; Naumann, R.; Kienast, M.; Song, S.-R.; Dresen, G.

2014-08-01

136

The Apollo 17 drill core - Petrologic systematics and the identification of a possible Tycho component  

NASA Technical Reports Server (NTRS)

Modal data support a five-unit stratigraphy for the Apollo 17 drill core. The upper unit E (0-22 cm depth) is marked by high content of fused soil, brown glass, and mare basalt fragments. This unit corresponds with a portion of the core excavated and refilled within the last 2 m.y. The underlying unit D (22071 cm depth) has a low abundance of fused soil (i.e., low maturity) and is rich in coarse (less than 200 microns) mare fragments. A large section of the core, unit C (71-224 cm depth), is finer-grained, more mature (richer in agglutinates), more feldspathic and has more highland lithic, mineral and glass fragments than unit D. The next underlying unit, B (224-256 cm depth), has yellow/colorless KREEP glasses with a high Si, low-alkali composition unlike the common Apollo 15 or Apollo 17 KREEP series. The petrologic (fused soil) and Is/FeO maturity of this layer is also lower than the units above and below. The deepest unit, A (256-284 cm depth), is marked by its relatively higher maturity and lower yellow/colorless KREEP glass content. The most prominent petrographic/stratigraphic indicators are the pyroxene-rich immature mare unit D and the abundance of KREEP glass in unit B. This KREEP glass is distinctive petrographically and compositionally, and is probably exotic to the Apollo 17 site. It is suggested here that the KREEP glass in unit B is derived from Tycho, which implies widespread distribution of KREEP on the lunar nearside.

Vaniman, D. T.; Labotka, T. C.; Papike, J. J.; Simon, S. B.; Laul, J. C.

1979-01-01

137

Invasion of drilling mud into gas-hydrate-bearing sediments. Part II: Effects of geophysical properties of sediments  

NASA Astrophysics Data System (ADS)

This study examines the dynamic behaviour of drilling-mud invasion into gas-hydrate-bearing sediment (GHBS) and the effects of such an invasion on wellbore stability and the reliability of well logging. The effects of mud properties on mud invasion into the GHBS are detailed in Part I. Here, we discuss the effects of sediment properties on mud invasion by considering the Chinese first gas-hydrate-drilling expedition in the South China Sea and other hydrate projects. Our simulation results further show that mud-invasion coupling hydrate dissociation and reformation is the main unique characteristic observed during mud invasion in GHBS compared with conventional oil/gas sediments. The appearance of a high-saturation hydrate ring during mud-invasion process is related to not only mud density, temperature and salinity but also sediment properties. On the whole, the effective permeability and initial hydrate saturation plays a critical role in mud invasion in GHBS. The effect of initial hydrate saturation, which corresponds to effective permeability and porosity on the mud invasion in SH7 is pronounced because initial hydrate saturations vary greatly. For pore-filling GHBS without fractures, well-logging results in high-saturation hydrate intervals are more reliable and accurate than those in low-saturation hydrate intervals. The log results at the interbeds with low-saturation hydrates are easily distorted by mud invasion.

Ning, Fulong; Wu, Nengyou; Yu, Yibing; Zhang, Keni; Jiang, Guosheng; Zhang, Ling; Sun, Jiaxin; Zheng, Mingming

2013-06-01

138

Tectonic implications deduced from drill cores in the Qaidam basin, NE Tibetan Plateau (Invited)  

NASA Astrophysics Data System (ADS)

The Qaidam Basin is the largest intermontane basin of the NE Tibetan Plateau and an ideal place to study the paleoenvironmental evolution and erosion history related to tectonic activity and climate change. We studied two cores of lacustrine sediments drilled in the western basin within a distance of about 25 km, the 940 m deep SG-1 core in the Chahansilatu sub-depression and the 723 m deep SG-1b core in the Jianshan anticline. These cores comprise fine-grained lacustrine sediments and according to our magnetostratigraphic results span the ages of ~2.8-1.1 Ma (SG-1) and ~7.3-1.6 Ma (SG-1b). The proxy record reveals a long-term drying trend, and several proxy parameters can be matched with the marine oxygen isotope curve indicating a tie to global climate change. However, overlying trends and stepwise changes of average sediment accumulation rates (SAR) point towards an influence of tectonic processes. The results of average SARs of core SG-1b show three intervals with relatively higher values from the bottom (>7.3 Ma) to 6.0 Ma, between 5.2 and 4.2 Ma and between 3.6 and 2.6 Ma. These phases are in temporal agreement with the deposition of thick coarse-grained deposits in other parts of the Qaidam basin, the development of the en-echelon s-shaped structure of the basin, the separation of the western basin into shallow subbasins and the formation of a large synclinal trough in the eastern basin, and tectonic activities at the north-eastern plateau and other plateau regions. Growth strata are crucial to interpret the fold-and-thrust geometry, and the kinematics modeled by variations of the sedimentation rate and the uplift rate in the folding region. Several features indicate that the geometry of growth strata at our study site has developed by limb rotation with clear changes of growth strata dip and thicknesses on the forelimb, rather than by kink-band migration. Comparison of the SARs from SG-1 and SG-1b demonstrates that the development of the limb rotation was controlled by overlap before ~1.6 Ma. Rapid uplift is indicated after ~1.6 Ma caused the occurrence of offlap and the termination of deposition at the Jianshan anticline region. This all can be probably related to pulse tectonic uplift of the NE Tibetan Plateau and fault-propagation-folding in the Qaidam Basin.

Appel, E.; Zhang, W.; Fang, X.; Song, C.; Setzer, F.; Herb, C.

2013-12-01

139

Practical guide for testing and maintenance of high temperature drilling fluids during drilling, coring, logging, and cementing wellbores  

SciTech Connect

Control of mud weight, fluid rheology, and loss of fluids from the mud system are the most important parameters that must be monitored and controlled during any drilling operation on a mud system. Also, alkalinity control is of paramount importance of systems where the pH is kept below 10.0 because of the differences in the chemical reactions on clays and precipitation of carbonates. Ideally, one must be able to duplicate down-hole conditions of temperature, pressure, shear stress and differential pressure between the column of fluid and the formation. Unfortunately, the instrumentation for monitoring the above is either very scarce, nonexistent, or does not completely duplicate downhole conditions. Therefore, a thorough working knowledge and understanding of chemical reactions from laboratory studies that will take place in a given system under downhole conditions is helpful. There should be a sound scientific foundation established for any phenomenon before attempting to apply it in field procedures and utilization. During the past several years the authors have conducted detailed research on a variety of clay minerals for use as a primary viscosifier for water base drilling fluids. The following is a review of their findings. 6 refs., 6 figs., 3 tabs.

Carney, L.L.; Guven, N. (Texas Tech Univ., Lubbock, TX (USA). Dept. of Geosciences)

1991-02-01

140

A new high altitude paleoclimate record from the first ice core drilled in the eastern European Alps: preliminary results  

NASA Astrophysics Data System (ADS)

Low latitude ice cores offer unique and detailed paleoclimate information from high elevations. Multiple proxies synchronized within the same ice medium offer the possibility to precisely link past climate variations to changes in the surrounding ecosystems and human activities, providing a unique paleo-geographic perspective of the Earth system. However, as most of the accessible low latitude drilling sites have already been exploited and as glaciers are melting worldwide, it is difficult to identify ice fields that contain novel and intact ice core records. We drilled the first ice cores to bedrock in the eastern European Alps during autumn 2011. These cores were extracted from the Alto dell'Ortles glacier (3859 m, South Tyrol, Italy) and their length was up to 75 m. The firn-ice transition was found at ~30 m depth. Below the temperate firn portion, cold ice layers sitting on frozen bedrock still exist and represent remnants from the colder climate before ~1980 AD. Analysis of beta emissions and tritium indicate the well-known 1963 peak (originating from radioactive nuclear fallout) to be at 41 m depth. Together with a measured density profile, this allows us to estimate an average accumulation rate of ~ 850 mm of water equivalent per year during the last 50 years. This confirms this drilling site as one with the lowest snow accumulation rate in the Alps, potentially containing older ice than most of the other Alpine glaciers. Preliminary analyses reveal that the deep and cold ice layers of this glacier preserve clearly distinguishable annual variations in stable isotopes, dust and major ions that can be precisely dated. Alto dell'Ortles is the first low-accumulation alpine drilling site where both winter and summer layers can be clearly identified. Application of a conventional flow model and preliminary annual layer counting suggest that the high altitude records contained in these ice cores may span at least several centuries.

Gabrielli, P.; Barbante, C.; Carturan, L.; Davis, M. E.; Dalla Fontana, G.; Dinale, R.; Dragà, G.; Gabrieli, J.; Kehrwald, N. M.; Mair, V.; Mikhalenko, V.; Oeggl, K.; Schotterer, U.; Seppi, R.; Thompson, L. G.; Tonidandel, D.

2012-12-01

141

Results of NanTroSEIZE Expeditions Stages 1 & 2: Deep-sea Coring Operations on-board the Deep-sea Drilling Vessel Chikyu and Development of Coring Equipment for Stage 3  

NASA Astrophysics Data System (ADS)

The Nankai-Trough Seismogenic Zone Experiment (NanTroSEIZE) has carried out several drilling expeditions in the Kumano Basin off the Kii-Peninsula of Japan with the deep-sea scientific drilling vessel Chikyu. Core sampling runs were carried out during the expeditions using an advanced multiple wireline coring system which can continuously core into sections of undersea formations. The core recovery rate with the Rotary Core Barrel (RCB) system was rather low as compared with other methods such as the Hydraulic Piston Coring System (HPCS) and Extended Shoe Coring System (ESCS). Drilling conditions such as hole collapse and sea conditions such as high ship-heave motions need to be analyzed along with differences in lithology, formation hardness, water depth and coring depth in order to develop coring tools, such as the core barrel or core bit, that will yield the highest core recovery and quality. The core bit is especially important in good recovery of high quality cores, however, the PDC cutters were severely damaged during the NanTroSEIZE Stages 1 & 2 expeditions due to severe drilling conditions. In the Stage 1 (riserless coring) the average core recovery was rather low at 38 % with the RCB and many difficulties such as borehole collapse, stick-slip and stuck pipe occurred, causing the damage of several of the PDC cutters. In Stage 2, a new design for the core bit was deployed and core recovery was improved at 67 % for the riserless system and 85 % with the riser. However, due to harsh drilling conditions, the PDC core bit and all of the PDC cutters were completely worn down. Another original core bit was also deployed, however, core recovery performance was low even for plate boundary core samples. This study aims to identify the influence of the RCB system specifically on the recovery rates at each of the holes drilled in the NanTroSEIZE coring expeditions. The drilling parameters such as weight-on-bit, torque, rotary speed and flow rate, etc., were analyzed and conditions such as formation, tools, and sea conditions which directly affect core recovery have been categorized. Also discussed will be the further development of such coring equipment as the core bit and core barrel for the NanTroSEIZE Stage 3 expeditions, which aim to reach a depth of 7000 m-below the sea floor into harder formations under extreme drilling conditions.

Shinmoto, Y.; Wada, K.; Miyazaki, E.; Sanada, Y.; Sawada, I.; Yamao, M.

2010-12-01

142

Development of a portable x-ray computed tomographic imaging system for drill-site investigation of recovered core  

SciTech Connect

A portable x-ray computed tomography (CT) system was constructed for imaging core at drill sites. Performing drill-site-based x-ray scanning and CT analysis permits rapid evaluation of core properties (such as density, lithologic structure, and macroporosity distribution) and allows for real-time decision making for additional core-handling procedures. Because of the speed with which scanning is performed, systematic imaging and electronic cataloging of all retrieved core is feasible. Innovations (such as a novel clamshell shielding arrangement integrated with system interlocks) permit safe operation of the x-ray system in a busy core handling area. The minimization of the volume encapsulated with shielding reduces the overall system weight and facilitates instrument portability. The x-ray system as originally fabricated had a 110 kV x-ray source with a fixed 300-micron focal spot size. A 15 cm image intensifier with a cesium iodide phosphor input screen was coupled to a CCD for image capture. The CT system has since been modified with a 130 kV micro-focal x-ray source. With the x-ray system's variable focal spot size, high-resolution studies (10-micron resolution) can be performed on core plugs and coarser (100-micron resolution) images can be acquired of whole drill cores. The development of an aluminum compensator has significantly improved the dynamic range and accuracy of the system. An x-ray filter has also been incorporated, permitting rapid acquisition of multi-energy scans for more quantitative analysis of sample mineralogy. The x-ray CT system has operated reliably under extreme field conditions, which have varied from shipboard to arctic.

Freifeld, Barry M.; Kneafsey, Timothy J.; Tomutsa, Liviu; Pruess, Jacob

2003-05-01

143

Alteration of hyaloclastites in the HSDP 2 Phase 1 Drill Core 1. Description and paragenesis  

NASA Astrophysics Data System (ADS)

The core from the Hawaii Scientific Drilling Project 2 Phase 1 provides a unique opportunity for studying the low-temperature alteration processes affecting basalt in suboceanic-island environments. In hyaloclastites, which make up about one half of the lower 2 km of this core (the portion that accumulated below sea level), these processes have resulted in zones of incipient, smectitic, and palagonitic alteration. The alteration of sideromelane in these hyaloclastites has four distinct outcomes: dissolution, replacement by two different textural varieties of smectite (i.e., reddened and green grain-replacive), and conversion to palagonite. All samples show evidence of the incipient stage of alteration, suggesting that every sample passed through that zone. However, most samples that show palagonitic alteration do not also show evidence of smectitic alteration and vice versa, suggesting these two outcomes represent divergent paths of alteration. Incipient alteration (1080 to 1335 m depth) includes fracturing and mechanical reduction of porosity from 40-45% to about 20-30%; growth of one form of pore-lining smectite; dissolution of sideromelane; and formation of sideromelane-grain replacements consisting of Fe-hydroxide-strained smectite, titaniferous nodules, and tubules. DNA-specific stains and morphological features indicate that tubules are the result of microbial activity. Smectitic alteration (1405 to 1573 m) includes growth of a second variety of pore-lining smectite, pore-filling and grain-replacing smectite, and cements of phillipsite and Ca-silicate minerals. Palagonitic alteration (1573 m to the deepest samples) includes replacement of margins of shards with palagonite and growth of pore-filling chabazite. The porosity is reduced by cementation to less than 4% at 1573 m. Porosity does not decrease further down hole, nor does the thickness of palagonite rims on shards increase through the zone of palagonitic alteration. In these samples, palagonite is not an intermediate alteration product in the development of smectite. Rather, in hyaloclastites from the HSDP core, palagonite has formed after all observed smectites. Current downhole temperatures at the boundaries between the three alteration zones are in the range from 12° to 15°C, suggesting that geochemical thresholds or vital effects, not temperature conditions, control different outcomes of alteration.

Walton, Anthony W.; Schiffman, Peter

2003-05-01

144

The Apollo 17 drill core - Chemistry of size fractions and the nature of the fused soil component  

NASA Technical Reports Server (NTRS)

It is shown that the Apollo 17 drill core 70009-70001 is heterogeneous with depth, containing five stratigraphic units, and has a bulk soil chemistry governed by the coarse fractions because of their greater weight proportions. The four components (1) KREEP, (2) anorthositic gabbro, (3) mare basalt, and (4) orange glass are used to model the compositions of the coarse and fine fractions of the entire drill core. It is found that the chemistry of the fused soil component in the five stratigraphic units is more similar to the chemistry of the fine, less than 20-micron fractions than the coarse fraction, suggesting that agglutinates may prefferentially meld and replicate the chemistry of the finer size fractions. The sources of Zn are the orange/black glasses, and the Zn profile is anticorrelated with the maturity index of Morris et al (1979), indicating the liberation of Zn during soil maturation.

Laul, J. C.; Papike, J. J.

1980-01-01

145

Can tephra be recognized in Hawaiian drill core, and if so, what can be learned about the explosivity of Hawaiian volcanoes?  

NASA Astrophysics Data System (ADS)

Nearly 6000 feet of drill core was recently recovered from the Pohakula Training Area (PTA) near the Saddle Road between Mauna Loa and Mauna Kea volcanoes on Hawaii Island. Drilling was funded by the US Army with an objective to find a potable water source; the rock core was logged and archived thanks to funding from the National Science Foundation. Within the first few hundred meters, alluvial outwash from the slopes of Mauna Kea is underlain by post-shield Mauna Kea lavas. Below this depth the core is predominantly pahoehoe and to a lesser extent a'a lavas expected to be from Mauna Kea's shield stage volcanism. During the logging effort, and throughout the core, a number of suspect-pyroclastic deposits were identified (largely based on particle texture). These deposits will be examined in more detail, with results presented here. An effort will be made to determine whether explosive deposits can, in fact, be unequivocally identified in drill core. Two anticipated challenges are differentiating between: scoria and 'clinker' (the latter associated with a'a lava flows), and primary volcanic ash, loess, and glacial sediments. Recognition of explosive deposits in the PTA drill core would lend insight into Mauna Kea's explosive history, and potentially that of other Big Island volcanoes as well. If the characteristics of tephra in Hawaiian drill core can be identified, core from the Hawaiian Scientific Drilling Project (HSDP) and Scientific Observation Holes (SOH-1,2,4) may also be examined.

Lautze, N. C.; Haskins, E.; Thomas, D. M.

2013-12-01

146

A composite lithology log while drilling  

SciTech Connect

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

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

1988-01-01

147

Development of a seismic borehole sonde for high resolution geophysical exploration ahead and around the drill bit  

NASA Astrophysics Data System (ADS)

The importance of exploration with high resolution increases more and more because reservoirs especially in geothermal fields are characterized of small-scale geological structures. Today, surface seismic surveys were often combined with borehole seismic measurements like VSP or SWD to improve the velocity model and to image the structures with higher resolution. The accuracy of structure localization depends strongly on the surveying depth. There is the need for resolution of such small-scale structures in the range of meters to explore deeper structures with a high resolution. In the project "Seismic Prediction While Drilling" (SPWD) a new approach for a seismic exploration method in boreholes will be examined. SPWD comprises the seismic sources and receivers in one device. This allows an exploration with a resolution independent from depth and a system development for an exploration ahead and around the drill bit. At first a prototype of a borehole device for dry horizontal boreholes in a mine was developed and tested. The source device consists of four magnetostrictive vibrators emitting sweep signals from 500 Hz to 5000 Hz. To achieve a radiation pattern for focusing the seismic wave energy in predefined directions the signals of each vibrator must be independently controlled in amplitude and phase. The adjustment of amplitudes and phases of each sweep signal resulting in constructive interference with a predefined direction. A control of the emitted signals is retained by 30 three-component receivers mounted along the surrounding galleries in distances of up to 50 m. In measurements several parameters were examined to control the radiation pattern. The enhancement and diminishment of the wave amplitudes in the predefined directions of the radiation pattern is clearly exhibited also a dependency of the frequency. Using a three-component Fresnel-Volume-Migration to image the reflected wave field the results show clearly the effect of the radiation pattern on the distribution of the seismic wave energy. The migration of the reflected wave field reveals an amplification of the reflected amplitudes at the galleries corresponding to the radiation pattern of the complex borehole source. Also, structures passing through the borehole can be detected with an additional characterization by different radiation patterns. Further improvements were realized in focusing the seismic energy with advances in technical devices and also in the control of the vibrators. As a next step a wireline prototype for borehole measurements was designed and constructed. Currently the manufacturing is in progress. This prototype will be used in vertical boreholes up to 2000 m depth. After completion first measurements are planned to verify the exploration method for a directional investigation in boreholes. The measurements will take place in different geologies of hard and soft rocks and also depths. Also the mine was expanded with a 70 m vertical borehole for further research aspects. This project is funded by the German Federal Environment Ministry.

Jaksch, K.; Giese, R.; Kopf, M.

2012-04-01

148

Records of Long-chain Alkenones From the Drilling Core in Lake Qinghai Over the Last 13,000 Years  

Microsoft Academic Search

We tended to concentrate on alkenone distribution patterns in Lake Qinghai region around 2005 and found the long-chain alkenones were widely distributed in surface water and modern sediments. Alkenone proxy could be used in palaeoenvironment change research in this region. In here, we present the C37 content, %C37:4 value and Uk'37 of lacustrine sediments from a drilling core LQDP05-1F of

W. Liu; Z. Wang; M. Fu; Z. An

2008-01-01

149

Quaternary paleoceanography of the central Arctic based on Integrated Ocean Drilling Program Arctic Coring Expedition 302 foraminiferal assemblages  

Microsoft Academic Search

(1) The Integrated Ocean Drilling Program (IODP) Arctic Coring Expedition (ACEX) Hole 4C from the Lomonosov Ridge in the central Arctic Ocean recovered a continuous 18 m record of Quaternary foraminifera yielding evidence for seasonally ice-free interglacials during the Matuyama, progressive development of large glacials during the mid-Pleistocene transition (MPT) ? 1.2-0.9 Ma, and the onset of high-amplitude 100-ka orbital

Thomas M. Cronin; Shannon A. Smith; Frédérique Eynaud; Matthew O'Regan; John King

2008-01-01

150

Thermal property and density measurements of samples taken from drilling cores from potential geologic media  

SciTech Connect

Density, steady-state conductivity, enthalpy, specific heat, heat capacity, thermal diffusivity and linear thermal expansion were measured on 59 materials from core drill samples of several geologic media, including rock salt, basalt, and other associated rocks from 7 potential sites for nuclear waste isolation. The measurements were conducted from or near to room temperature up to 500/sup 0/C, or to lower temperatures if limited by specimen cracking or fracturing. Ample documentation establishes the reliability of the property measurement methods and the accuracy of the results. Thermal expansions of salts reached 2.2 to 2.8 percent at 500/sup 0/C. Associated rocks were from 0.6 to 1.6 percent. Basalts were close to 0.3 percent at 500/sup 0/C. Specific heats of salts varied from 0.213 to 0.233 cal g/sup -1/C/sup -1/, and basalts averaged 0.239 cal g/sup -1/C/sup -1/. Thermal conductivities of salts at 50/sup 0/C were from 0.022 to 0.046 wcm/sup -1/C/sup -1/, and at 500/sup 0/C, from 0.012 to 0.027 wcm/sup -1/C/sup -1/. Basalts conductivities ranged from 0.020 to 0.022 wcm/sup -1/C/sup -1/ at 100/sup 0/C and 0.016 to 0.018 at 500/sup 0/C. There were no obvious conductivity trends relative to source location. Room temperature densities of salts were from 2.14 to 2.29 gcm/sup -3/, and basalts, from 2.83 to 2.90 gcm/sup -3/. The extreme friability of some materials made specimen fabrication difficult. 21 references, 17 figures, 28 tables.

Lagedrost, J.F.; Capps, W.

1983-12-01

151

Paleomagnetic records of core samples of the plate-boundary thrust drilled during the IODP Japan Trench Fast Drilling Project (JFAST)  

NASA Astrophysics Data System (ADS)

IODP Expedition 343, Japan Trench Fast Drilling Project (JFAST), drilled across the plate-boundary décollement zone near the Japan Trench where large slip occurred during the March 2011 Tohoku-oki earthquake. We conducted paleomagnetic measurements of the core sample retrieved from the highly-deformed sediments comprising the plate-boundary décollement zone. Whole-round samples for structural analyses from five depth intervals of the core (0-12 cm, 12-30 cm, 43-48 cm, 48-58 cm, and 87.5-105 cm), were trimmed into oriented slabs with typical dimensions of 3x3x5 cm that are now being used to make petrographic sections for microstructural and chemical study. The remainder of the core sample was split into working and archive halves. We measured remanent magnetization of 16 trimmed slabs and the archive half of the core sample. The slabs were subjected to natural remanent magnetization (NRM) measurements in 0.5-1 cm intervals and progressive alternating field demagnetization (AFD) up to 80 mT with a 2G755 pass-through superconducting rock magnetometer at Kochi University. The archive half of the core sample was subjected to NRM measurement and AFD up to 20 mT with a 2G760 superconducting rock magnetometer installed on R/V Chikyu. Typically, two or three paleomagnetic components were isolated during the AFD of slab samples up to 80 mT. One ';soft' component was demagnetized below 20-30 mT, and another ';hard' component was not demagnetized even with AFD in 80 mT. A third component may be separated during AFD at the intermediate demagnetizing field, and may overlap the soft and hard components. The multiple slab samples cut from an identical whole-round sample have generally consistent paleomagnetic direction of the hard component. Contrastingly, the direction of the soft component is less consistent between adjacent slabs, and even varies within a single slab. The direction variation of the soft component possibly reflects the cm-scale strain and rotation of the highly-deformed sediments within the plate-boundary décollement zone. Studies of the relationship of the direction variation to the microstructure are ongoing, and will be reported at the meeting. The consistency of the hard component direction within highly deformed sediment implies it was recently acquired. Further studies of the acquisition mechanism of the hard component are also intended.

Mishima, T.; Yang, T.; Ujiie, K.; Kirkpatrick, J. D.; Chester, F. M.; Moore, J. C.; Rowe, C. D.; Regalla, C.; Remitti, F.; Kameda, J.; Wolfson-Schwehr, M.; Bose, S.; Ishikawa, T.; Toy, V. G.

2013-12-01

152

Drilling overdeepened Alpine Valleys (DOVE)  

NASA Astrophysics Data System (ADS)

A recently submitted ICDP drilling proposal targets formerly glaciated areas, which are often characterized by deeply incised structures filled by thick Quaternary deposits. These buried troughs and valleys were formed by glacial overdeepening, likely caused by pressurized subglacial meltwater below warm-based glaciers. The proposed multinational drilling initiative consists of 14 drill sites in six different countries, all linked by the fact that they surround a formerly glaciated, densely populated mountain range, the European Alps. Being the best studied mountain range, the Alps will serve as textbook example allowing application of drilling results to other glaciated areas around the world. The drill holes, to be cored all the way to bedrock, will explore the type and age of the infillings of these overdeepened troughs. Such drill cores, paired with matching geophysical and instrumental data, hold the keys to understand how and how fast mountain ranges and their foreland are shaped by repetitive glaciations. The overarching goal will be to date the age and extent of past glaciations and their connection to paleoclimate, paleoecology and landscape history. As of today, it is not known how these glaciations varied along and across the Alps during the past, and to what extent the ice build-up along and across the Alps reflects changes in atmospheric circulation patterns. First results of drill holes in similar settings have produced local knowledge of the timing of glacial activity. Only an alpine-wide drilling initiative, however, will allow to reconstruct the full spatial and temporal scale of glacier advances and erosion and related landscape-forming processes over several glacial-interglacial cycles. Next to these paleoglacial, paleoecological and paleoclimatic aspects, the thick valley fills hold large, untapped aquifers. In the light of an increasing demand for water resources likely amplified by the projected climate change, testing these aquifers in the framework of this project is of high relevance for future hydrogeological applications. Related to this role, these drill holes may be used for shallow geothermal applications, which, however, to date rely on poorly constrained physical properties of the infilling sections. In addition, the areas represent areas of high seismic hazards related to their unfavorable seismic site effects. All these goals will be first addressed by state-of-the-art geophysical surveys that quantify the geometry of the overdeepenings. Drillholes will be analyzed by downhole logging, groundwater sampling and subsurface biosphere testing. Sedimentological, geochemical and palaeobiological analyses will characterize the sediment cores, and a combination of different approaches (biostratigraphy, luminescence dating, cosmogenic nuclide dating, magnetostratigraphy, and tephrastratigraphy) will establish the chronological framework. Eventually, the results from the above approaches will be cross-checked with the outcome of modeling both glacial flow and erosion and atmospheric circulation.

Anselmetti, Flavio S.; Preusser, Frank; Bavec, Milos; Crouzet, Christian; Fiebig, Markus; Gabriel, Gerald; Ravazzi, Cesare; Spoetl, Christoph

2014-05-01

153

Core Angular Momentum and the IERS Sub-Centers Activity for Monitoring Global Geophysical Fluids. Part 1; Core Angular Momentum and Earth Rotation  

NASA Technical Reports Server (NTRS)

The part of the grant was to use recordings of seismic waves travelling through the earth's core (PKP waves) to study the inner core rotation and constraints on possible density anomalies in the fluid core. The shapes and relative arrival times of such waves associated with a common source were used to reduce the uncertainties in source location and excitation and the effect of unknown mantle structure. The major effort of the project is to assemble historical seismograms with long observing base lines. We have found original paper records of SSI earthquakes at COL between 1951 and 1966 in a warehouse of the U.S. Geological Survey office in Golden, Colorado, extending the previous measurements at COL by Song and Richards [1996] further back 15 years. Also in Alaska, the University of Alaska, Fairbanks Geophysical Institute (UAFGI) has been operating the Alaskan Seismic Network with over 100 stations since the late 1960s. Virtually complete archives of seismograms are still available at UAFGI. Unfortunately, most of the archives are in microchip form (develocorders), for which the use of waveforms is impossible. Paper seismograms (helicorders) are available for a limited number of stations, and digital recordings of analog signals started around 1989. Of the paper records obtained, stations at Gilmore Dome (GLM, very close to COL), Yukon (FYU), McKinley (MCK), and Sheep Creek Mountain (SCM) have the most complete continuous recordings.

Song, Xia-Dong; Chao, Benjamin (Technical Monitor)

1999-01-01

154

On the joint inversion of geophysical data for models of the coupled core-mantle system  

NASA Technical Reports Server (NTRS)

Joint inversion of magnetic, earth rotation, geoid, and seismic data for a unified model of the coupled core-mantle system is proposed and shown to be possible. A sample objective function is offered and simplified by targeting results from independent inversions and summary travel time residuals instead of original observations. These data are parameterized in terms of a very simple, closed model of the topographically coupled core-mantle system. Minimization of the simplified objective function leads to a nonlinear inverse problem; an iterative method for solution is presented. Parameterization and method are emphasized; numerical results are not presented.

Voorhies, Coerte V.

1991-01-01

155

Hawaiian Volcano Flank Stability Appraised From Strength Testing the Hawaiian Scientific Drilling Project's (HSDP) 3.1-km Drill Core  

NASA Astrophysics Data System (ADS)

Strength results from limited testing of HSDP core samples reveal significant differences in their unconfined compressive and shear strength. The median strength values show a progressive increase from the incipient (2.4 MPa) to smectitic (4.2 MPa) to palagonitic (9.4 MPa) alteration zones. The strength differences include differences among hyaloclastites as a function of their alteration, as well as differences between hyaloclastites and the various forms of lava flows and intrusive bodies. The unconfined compressive strengths of extrusive submarine and subaerial lavas and intrusive rocks from the HSDP core samples are much greater than that of any of the hyaloclastites, and range from 82 to 150 MPa. The cohesive shear strengths of hyaloclastites increase successively with depth and type of alteration (from 0.9 MPa for the incipient zone to 3.2 MPa for the palagonite zone). Conversely, the frictional strengths of the hyaloclastites show a decrease with increasing depth and alteration zone (from 17.6° for hyaloclastites from the incipient zone to 13.7° for the palagonitic zone). The Mohr strength envelope changes from a linear relationship at shallow depth to become curvilinear with increasing depth and consequently shows higher cohesion and lower friction. Comparison of the three groups of the altered hyaloclastites showed that they had p values < 0.05, and that the mean strength results from the incipient, smectitic and palagonitic altered hyaloclastites were significantly different from each other. The greatest difference was calculated between the mean value of the palagonitic alteration and the mean values from the smectitic and incipient alteration though subsequent statistical testing showed that the means of the incipient and smectitic alteration were not significantly different from each other. The palagonitic mean remains significantly different from both the incipient and smectitic means. No statistically significant difference was found in comparing the means of the basaltic flows, intrusive and pillow lava values. The test results imply that shallow rotational slumps that develop within the upper few kilometers of spreading Hawai'ian volcanoes within low strength, poorly-consolidated, smectite-rich hyaloclastites are similar to those we have found from the incipient and smectitic alteration zones of the HSDP cores. Deeper slumps might be directed through over-pressured pillow lava units as a result of the stronger pillow lava units permitting deeper failure surfaces to develop. Petrographically the Mauna Kea hyaloclastites appear similar to those from actively spreading Hawai'ian shield volcanoes. Alteration processes apparently affect the strength of these hyaloclastites. In the shallower zones of incipient and smectitic alteration, hyaloclastites generally retain their high primary porosities. In the deeper, palagonitic zone of alteration, the hyaloclastites gain both compressive and shear strength, primarily through consolidation and zeolitic cementation. The marked strength contrast between hyaloclastites, and the lavas that overlie and underlie them is significant, and may be a primary factor in localizing the destabilization of the flanks of Hawaiian volcanoes.

Thompson, N.; Watters, R. J.; Schiffman, P.

2005-12-01

156

A geophysical study of oceanic core complexes and surrounding terrain, Mid-Atlantic Ridge 13°N-14°N  

NASA Astrophysics Data System (ADS)

We describe a geophysical study of oceanic core complexes (OCC) and surrounding seafloor on the Mid-Atlantic Ridge at 13°N-14°N and off-axis to ˜1.9 Myr. Data include a detailed, deep-towed side scan sonar, magnetic field and bathymetry survey, supplemented by concurrent sea-surface bathymetry, magnetic field and gravity measurements. Using side scan and bathymetry, we infer areas and relative ages of seafloor volcanism, revealing a complex pattern of melt accretion across the median valley including close to its walls. We estimate tectonic and magmatic extension throughout the area, and find that average tectonic extension since chron 2 on plates containing OCCs is up to three times that on their conjugates. Deep-towed magnetic data reveal asymmetric spreading (faster on OCC-containing plates) and crustal magnetization that is highly heterogeneous on a scale of ˜5 km, suggesting that exhumed domes of OCCs have highly variable lithologies, perhaps comprising both serpentinized peridotite and gabbro. Improved fits to magnetic data are provided by models incorporating ˜45°of OCC footwall rotation. An axial zone of normal magnetization, of presumed Brunhes epoch, has highly variable width and amplitude, with parts of the ridge axis displaying very low or apparently reversed magnetization. Gravity requires that OCCs have dense cores capped by lower density zones several kilometers thick. Gravity data indicate longer term patterns of crustal thickness and melt distribution that are broadly consistent with numerical models of OCC formation and show that waxing magmatism may terminate OCCs.

Mallows, C.; Searle, R. C.

2012-06-01

157

A composite lithology log while drilling  

SciTech Connect

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

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

1988-02-01

158

Plio-Pleistocene evolution of the southern Victoria Land climate system as seen in New Harbor drill cores  

NASA Astrophysics Data System (ADS)

The Taylor Valley (DVDP-10, -11) and Ferrar Fiord (CIROS-2) drill cores offer a window into the history of Southern Victoria Land glaciers and the Antarctic climate system during the late- Neogene. Here we present new paleomagnetic studies from these drill cores which date five phases of sedimentation in the Taylor/Ferrar fiords and reveal a climate modulation of magnetic mineralogy in southern Victoria Land during the late Neogene. Magnetostratigraphies were constructed from stepwise AF and/or thermal demagnetisation of discrete specimens from drill cores. Correlation of magnetostratigraphies with the magnetic polarity timescale was guided by biostratigraphic and radiometric constraints. Environmental magnetic studies were conducted to determine changes in concentration, gainsize and magnetic mineralogy through time. A parallel rock magnetic study was also conducted of regional basement rocks to quantify the source of magnetic minerals. The new ages models and environmental magnetic records indicate that during the latest Miocene - early Pliocene, wet based glaciers filled the Taylor and Ferrar fiords and that glaciers retreated during the Pliocene warm period leaving open marine conditions and deep fiords (>300 m). Magnetic minerals in these sediments are variably oxidised indicating terrestrial soil formation and probably warmer and wetter conditions at a time when the Ross Sea was free of ice and sea surface temperatures were 5°C warmer than today. We recognise the first significant cooling in DVDP-11 after 2.6 Ma by a shift to current winnowed sediments sourced from the Ross Sea. After 1.7 Ma sediments are almost exclusively lacustrine and were deposited in ice dammed lakes which formed when West Antarctic ice expanded across the Ross Embayment and abutted the Transantarctic Mountains. Magnetic mineralogy after ~2.6 Ma is dominated by a ubiquitous, paramagnetic component which coincides with the shift from warmer/wetter, sub-polar conditions to dry, polar dominated conditions.

Ohneiser, C.; Wilson, G. S.

2012-04-01

159

Development of Oceanic Core Complexes on the Mid-Atlantic Ridge at 13-14N: Deep-Towed Geophysical Measurements and Detailed Seafloor Sampling  

NASA Astrophysics Data System (ADS)

The first scientific cruise of research vessel James Cook in March-April 2007 targeted the Mid-Atlantic Ridge at 13-14°N, to investigate details of lithospheric generation and development in a low-magmatic setting. Overall objectives were to 1) investigate the 3D pattern of mantle upwelling and melt focusing; 2) study how plate accretion and separation mechanisms differ between magma-rich and magma-poor areas; and 3) test mechanisms of detachment faulting and extensional strain localisation in the lower crust and upper mantle. Smith et al. (Nature 2006) had shown this to be an area of widespread detachment faulting and formation of oceanic core complexes (OCC), and published bathymetry showed an extensive area of blocky rather than lineated topography, which elsewhere has correlated with areas of low effusive magmatism. We conducted a TOBI deep-towed geophysical survey over a 70 km length of ridge extending to magnetic chron C2n (1.9 Ma) on each flank. This included sidescan sonar and high resolution bathymetry and magnetic measurements on 13 E-W tracks spaced 3 - 6 km apart. The area includes 1 active, 1 dying, and 1 defunct OCC and borders well-lineated, apparently magmatically robust seafloor to the north. The geophysical survey was complimented by recovery of 7 oriented and 18 unoriented core and 29 dredge samples, including some from a probable OCC south of the TOBI survey. Deep-towed sidescan, bathymetry and video show the OCCs typically comprise a steeply outward tilted volcanic ridge marking the breakaway (as suggested by Smith et al., 2006); a high, rugged central massif that is complexly deformed as a result of uplift and bending, and may be separated from the breakaway ridge by what we interpret as a late outward dipping normal fault; and a smooth, corrugated surface that generally dips c. 20° towards the ridge axis at the termination but gradually rotates to horizontal or gently outward dipping near its junction with the central massif. Older OCCs have flatter central areas than the youngest OCC, perhaps as a result of unbending late in their development. They also have steep, ridge-dipping normal faults at or near their terminations that may play a role in ending the detachment faulting. The axial neovolcanic zone is absent or poorly developed opposite the active and dying OCCs, and appears to be propagating towards them, thus playing an important part in terminating OCC activity. We recovered peridotite from the central parts of the three northern OCCs, the median valley walls near 13°00'N, and the neovolcanic ridge near the OCC at 13°20'N. Basalt was recovered from the breakaway ridges and often the central massifs. Most of the corrugated surfaces were extensively covered in sediment and basaltic rubble which prevented us obtaining drill samples, though dredging recovered peridotite, fault rocks and basalt rubble. The toes of the 13°30'N and 13°20'N OCCs showed evidence of extensive and some recent hydrothermal activity. Basalt and fresh glass were recovered from axial volcanic ridges. We recovered very little gabbro. A reasonably coherent magnetic central anomaly is seen in the sea-surface field, but the higher-resolution deep- towed magnetic data reveal a pattern of crustal magnetisation that does not obviously match a simple reversal history, even in areas away from obvious OCCs. We are modelling these results in terms of asymmetric spreading, ridge jumping and tectonic rotations varying in time and space.

Searle, R.; MacLeod, C.; Murton, B.; Mallows, C.; Casey, J.; Achenbach, K.; Unsworth, S.; Harris, M.

2007-12-01

160

Influence of Steel Reinforcement on In-Situ Stress Evaluation in Concrete Structures by the Core-Drilling Method  

SciTech Connect

The core-drilling method is an emerging technique for evaluating in-situ stress in a concrete structure. A small hole is drilled into the structure, and the deformations in the vicinity of the hole are measured and related via elasticity theory to the stress. The method is similar to the ASTM hole-drilling strain-gauge method excepting that displacements rather than strains are the measured quantities. The technique may be considered nondestructive since the ability of the structure to perform its function is unaffected, and the hole is easily repaired. Displacement measurements in the current work are performed using 3D digital image correlation and industrial photogrammetry. The current paper addresses perturbations in the method caused by steel reinforcement within the concrete. The reinforcement is significantly stiffer than the surrounding concrete, altering the expected displacement field. A numerical investigation performed indicates an under-prediction of stress by as much as 18 percent in a heavily reinforced structure, although the effect is significantly smaller for more common amounts of reinforcement.

McGinnis, M. J.; Pessiki, S. [Lehigh University Dept. of Civil and Environmental Engineering, Bethlehem, PA 18015 (United States)

2006-03-06

161

Theoretical formulation of the core drilling method to evaluate stresses in concrete structures  

Microsoft Academic Search

The hole drilling method is an ASTM Standard Test Method that is used to evaluate residual stresses in isotropic linearly elastic materials. In civil engineering, the method is often used to evaluate stresses in metal structures. However, the method is not applicable to concrete because the heterogeneous composition of concrete prevents strain measurements from being made over small gage lengths.

Stephen Pessiki; Hakan Turker

2000-01-01

162

Methane hydrate pore saturation evaluation from geophysical logging and pressure core analysis, at the first offshore production test site in the eastern Nankai Trough, Japan  

NASA Astrophysics Data System (ADS)

On March 2013, the first offshore production test form methane hydrate (MH) concentrated zone (MHCZ) was conducted by the Research Consortium for Methane Hydrate Resource Development in Japan (MH21) at the AT1 site located in the north-western slope of Daini-Atsumi Knoll in the eastern Nankai Trough, Japan. Before the production test, extensive geophysical logging and pressure coring using Hybrid Pressure Coring System were conducted in 2012 at monitoring well (AT1-MC) and coring well (AT1-C), in order to obtain basic information for the MH reservoir characterization. MH pore saturation (Sh) is one of the important basic parameters not only for reservoir characterization, but also the resource assessment. However, precise evaluation of Sh from geophysical logging is still challenging technical issue. The MHCZ confirmed by the geophysical logging at AT1-MC has a turbidite assemblage (from several tens of centimeters to a few meters) with 60 m of gross thickness; it is composed of lobe/sheet type sequences in the upper part, and relatively thick channel sand sequences in the lower part. In this study, the Sh evaluated from geophysical logging data were compared with those evaluated from pressure core analysis. Resistivity logs and nuclear magnetic resonance (NMR) log were used for the Sh evaluation by geophysical logging. Standard Archie equation was applied for Sh evaluation from resistivity log, while density magnetic resonance (DMR) method was used for Sh evaluation from NMR log. The Sh from pressure core samples were evaluated using the amount of dissociated gas volume, together with core sample bulk volume, measured porosity, net sand intervals, and assumed methane solubility in pore water. In the upper part of the MHCZ, Sh estimated from resistivity log showed distinct difference in value between sand and mud layers, compared to Sh from NMR log. Resistivity log has higher vertical resolution than NMR log, so it is favorable for these kinds of thin bed evaluation. In this part, 50 to 80% of Sh was observed in sandy layer, which showed fairly good agreement with core derived Sh. On the other hand, lower part of the MHCZ, Sh estimated from both resistivity and NMR log showed higher background value and relatively smoother curve than upper part. In this part, 50 to 80% of Sh was observed in sandy layer, which was also showed good agreement with core derived Sh. This study was conducted by the Research Consortium for Methane Hydrate Resource Development in Japan (MH21).

Fujii, T.; Suzuki, K.; Takayama, T.; Konno, Y.; Yoneda, J.; Egawa, K.; Ito, T.; Nagao, J.

2013-12-01

163

Whole-rock analyses of core samples from the 1988 drilling of Kilauea Iki lava lake, Hawaii  

USGS Publications Warehouse

This report presents and evaluates 64 major-element analyses of previously unanalyzed Kilauea Iki drill core, plus three samples from the 1959 and 1960 eruptions of Kilauea, obtained by X-ray fluorescence (XRF) analysis during the period 1992 to 1995. All earlier major-element analyses of Kilauea Iki core, obtained by classical (gravimetric) analysis, were reported and evaluated in Helz and others (1994). In order to assess how well the newer data compare with this earlier suite of analyses, a subset of 24 samples, which had been analyzed by classical analysis, was reanalyzed using the XRF technique; those results are presented and evaluated in this report also. The XRF analyses have not been published previously. This report also provides an overview of how the chemical variations observed in these new data fit in with the chemical zonation patterns and petrologic processes inferred in earlier studies of Kilauea Iki.

Helz, Rosalind Tuthill; Taggart, Joseph E. Jr.

2010-01-01

164

Geophysical evidence for the evolution of the California Inner Continental Borderland as a metamorphic core complex  

USGS Publications Warehouse

We use new seismic and gravity data collected during the 1994 Los Angeles Region Seismic Experiment (LARSE) to discuss the origin of the California Inner Continental Borderland (ICB) as an extended terrain possibly in a metamorphic core complex mode. The data provide detailed crustal structure of the Borderland and its transition to mainland southern California. Using tomographic inversion as well as traditional forward ray tracing to model the wide-angle seismic data, we find little or no sediments, low (?6.6 km/s) P wave velocity extending down to the crust-mantle boundary, and a thin crust (19 to 23 km thick). Coincident multichannel seismic reflection data show a reflective lower crust under Catalina Ridge. Contrary to other parts of coastal California, we do not find evidence for an underplated fossil oceanic layer at the base of the crust. Coincident gravity data suggest an abrupt increase in crustal thickness under the shelf edge, which represents the transition to the western Transverse Ranges. On the shelf the Palos Verdes Fault merges downward into a landward dipping surface which separates "basement" from low-velocity sediments, but interpretation of this surface as a detachment fault is inconclusive. The seismic velocity structure is interpreted to represent Catalina Schist rocks extending from top to bottom of the crust. This interpretation is compatible with a model for the origin of the ICB as an autochthonous formerly hot highly extended region that was filled with the exhumed metamorphic rocks. The basin and ridge topography and the protracted volcanism probably represent continued extension as a wide rift until ?13 m.y. ago. Subduction of the young and hot Monterey and Arguello microplates under the Continental Borderland, followed by rotation and translation of the western Transverse Ranges, may have provided the necessary thermomechanical conditions for this extension and crustal inflow.

ten Brink, Uri S.; Zhang, Jie; Brocher, Thomas M.; Okaya, David A.; Klitgord, Kim D.; Fuis, Gary S.

2000-01-01

165

Source and Crystallization Characteristics of Basalts in the Kimama core: Project Hotspot Snake River Scientific Drilling Project, Idaho  

NASA Astrophysics Data System (ADS)

Mineral chemistry and petrography of basalts from the Kimama drill core recovered by Hotspot: Snake River Scientific Drilling Project, Idaho establish crystallization conditions of these lavas. Twenty-three basalt samples, from 20 individual lava flows were sampled from the upper 1000 m (of the 1912 m drilled) core drilled on the axis of the Snake River Plain, and represent approximately 3 m.y. of volcanism (rocks at the bottom of the hole are ~6 Ma). Rock from the upper 1000 m are typically fresh, while those lower in the core are more altered and are less likely to preserve fresh phenocrysts to analyze. Intratelluric phenocrysts (pre-eruption) are: olivine, plagioclase and Cr-spinel inclusions in olivine and plagioclase; groundmass phases (post-eruption) are: olivine, plagioclase, clinopyroxene, magnetite and ilmenite. Olivine core compositions range from Fo84-68, plagioclase cores range from An80-62, clinopyroxene ranges in composition from Wo47-34, En47-28, Fs30-15, spinel inclusions are Cr (up to 20 wt % Cr2O3) and Al-rich (up to 35 wt % Al2O3) and evolve to lower concentrations of Cr and Al and higher Fe and Ti, chromian titanomagnetite to magnetite, and ilmenite are groundmass oxide phases. Thermobarometry of Kimama core basalts indicates that the phenocryst phases crystallized at temperatures of 1155 to 1255°C at depths of 7 to 17 km, which is within or near the seismically imaged mid-crustal sill. Plagioclase hygrometry suggests that these lavas are relatively anhydrous with less than 0.4 wt % H2O. Groundmass phases crystallized at lower temperatures (<1140°C) after eruption. Oxygen fugacity inferred from Fe-Ti oxide equilibria is at or just below the QFM buffer. The origin of the basaltic rocks of the Snake River Plain has been attributed to a mantle plume or to other, shallow mantle processes. Mineral and whole rock major and trace element geochemistry of the olivine tholeiites from the Kimama core are used to distinguish between these two sources (deep or shallow mantle). Whole rock compositions were corrected for plagioclase and olivine fractionation to calculate primary liquids to estimate mantle potential temperatures. Olivine phenocrysts have the pyroxenite source characteristics of low Mn and Ca, but a peridotite source characteristic of low Ni. Thus, trace element models were used to test whether there is pyroxenite in the source of the Snake River Plain basalts, as hypothesized for Hawaii and other plume-related hotspots (e.g., Sobolev et al., 2005; Herzberg, 2011). Olivine chemistry and trace element models establish that the basalt source is a spinel peridotite, not a pyroxenite. The average mantle potential temperature obtained for these samples is 1577°C, 177°C hotter than ambient mantle, suggesting that the basaltic liquids were derived from a thermal plume. Silica activity barometry shows that melt segregation occurs between 80 and 110 km depth, which is within or very near the spinel stability field, and suggests that the lithosphere has been eroded by the plume to a maximum depth of 80 km, and recent mantle tomography suggests that it may be even thinner.

Bradshaw, R. W.; Christiansen, E. H.; Dorais, M. J.; Shervais, J. W.; Potter, K. E.

2012-12-01

166

Brines and interstitial brackish water in drill cores from the deep gulf of Mexico  

USGS Publications Warehouse

Marked increases in interstitial salinity occur in two drill holes located in the Gulf of Mexico at a water depth of more than 3500 meters. The increases probably arose through diffusion of salt from buried evaporites. In one hole, however, brackish water was encountered on penetrating the oil-permeated cap rock of a salt dome. The phenomenon is attributed to production of fresh water during oxidation of petroleum hydrocarbons and decomposition of gypsum to form native sulfur.

Manheim, F. T.; Sayles, F. L.

1970-01-01

167

Status Report: Prospect Drilling Technique.  

National Technical Information Service (NTIS)

An attempt is made to give a survey of the available drilling systems (processes and equipment), which are used in prospect drilling. Starting from the diamond core drilling technique system, the systems are described which can be distinguished according ...

J. Behrens C. Marx H. Schlueter

1981-01-01

168

An ultra-clean firn core from the Devon Island Ice Cap, Nunavut, Canada, retrieved using a titanium drill specially designed for trace element studies.  

PubMed

An electromechanical drill with titanium barrels was used to recover a 63.7 m long firn core from Devon Island Ice Cap, Nunavut, Canada, representing 155 years of precipitation. The core was processed and analysed at the Geological Survey of Canada by following strict clean procedures for measurements of Pb and Cd at concentrations at or below the pg g(-1) level. This paper describes the effectiveness of the titanium drill with respect to contamination during ice core retrieval and evaluates sample-processing procedures in laboratories. The results demonstrate that: (1) ice cores retrieved with this titanium drill are of excellent quality with metal contamination one to four orders of magnitude less than those retrieved with conventional drills; (2) the core cleaning and sampling protocols used were effective, contamination-free, and adequate for analysis of the metals (Pb and Cd) at low pg g(-1) levels; and (3) results from 489 firn core samples analysed in this study are comparable with published data from other sites in the Arctic, Greenland and the Antarctic. PMID:16528426

Zheng, J; Fisher, D; Blake, E; Hall, G; Vaive, J; Krachler, M; Zdanowicz, C; Lam, J; Lawson, G; Shotyk, W

2006-03-01

169

The 1997 core drilling through Ordovician and Silurian strata at Ro??sta??nga, S. Sweden: Preliminary stratigraphic assessment and regional comparison  

USGS Publications Warehouse

A core drilling at Ro??sta??nga, the first such drilling ever undertaken in this classical Lower Paleozoic outcrop area in W-central Scania, penetrated an approximately 96 m thick succession of Lower Silurian-upper Middle Ordovician marine rocks. The drilling was stopped at a depth of 132.59 m in an interval of crushed rocks, probably a prominent fault zone, that proved impossible to drill through. The core contains a stratigraphical sequence from the basal Upper Llandoverian (Telychian Stage) to the upper Middle Ordovician (Harjuan Stage). The following units are recognized in descending stratigraphic order (approximate thickness in parenthesis): Kallholn Formation (35 m), Lindega??rd Mudstone (27 m), Fja??cka Shale (13 m), Mossen Formation (0.75 m), Skagen Formation (2.5 m), and Sularp Shale (19 m+). Except for the Skagen Formation, the drilled sequence consists of shales and mudstones with occasional thin limestone interbeds and is similar to coeval successions elsewhere in Scania. There are 11 K-bentonite beds in the Kallholn Formation, 2(3?) in the Lindega??rd Mudstone, 1 in the Mossen Formation, 7 in the Skagen Formation, and 33 in the Sularp Shale. The core serves as an excellent Lower Silurian-upper Middle Ordovician reference standard not only for the Ro??sta??nga area but also for southernmost Sweden in general because the cored sequence is the stratigraphically most complete one known anywhere in this region.

Bergstrom, S. M.; Huff, W. D.; Koren', T.; Larsson, K.; Ahlberg, P.; Kolata, D. R.

1999-01-01

170

Records of Long-chain Alkenones From the Drilling Core in Lake Qinghai Over the Last 13,000 Years  

NASA Astrophysics Data System (ADS)

We tended to concentrate on alkenone distribution patterns in Lake Qinghai region around 2005 and found the long-chain alkenones were widely distributed in surface water and modern sediments. Alkenone proxy could be used in palaeoenvironment change research in this region. In here, we present the C37 content, %C37:4 value and Uk'37 of lacustrine sediments from a drilling core LQDP05-1F of Lake Qinghai. (The 14C chronology is from Zhou et al, unpublished data). C37 contents range from 0.6 to 60 g/g around the average value of 10 g/g and represent several significant higher values stages in the Holocene, which reflects greater biomass level of LCAs producer algae's. In the other words, it is records the producer algae's suitable growth period and the information of algae growth environment. The long period existence of LCAs in drilling core also indicates that it can be used as a continuous biological proxy in Lake Qinghai over late Pleistocene. Based on the recognition of %C37:4 distribution of modern Lake Qinghai, there is negative correlation between %C37:4 value and salinity within a certain salinity range. The salinity indicated by %C37:4 values represent three stages of different change trends over the last 13 kyr. From late Pleistocene to early Holocene, %C37:4 range from 5.9 to 42.7% and salinity shows several significant fluctuations. During middle Holocene, %C37:4 values firstly stabilize on the lower level around the average value 17% and increase to 60%, a lower salinity exhibit in this period. During the late Holocene, the salinity change strongly with significant fluctuations of %C37:4, the variation range over 40%. We suggest it can be used to explain the salinity changes in three stages by the interaction of the climate change and the evolution of Lake Qinghai. Uk'37 values change slightly around the average value of 0.17 during the late Pleistocene generally. However, it shows several significant peaks of higher values respectively, which is difficult to explain by the usual recognition of temperature change during the Holocene period. We suggest that Uk'37 is still strongly effected by other environment factors in Lake Qinghai or other closed interior brackish-salt lakes, except for the temperature of lake water. It needs more mechanisms research of modern LCAs distribution in Lake Qinghai. Keywords: long-chain alkenones, Lake Qinghai, drilling core

Liu, W.; Wang, Z.; Fu, M.; An, Z.

2008-12-01

171

Project Hotspot: Mineral chemistry of high-MgO basalts from the Kimama core, Snake River Scientific Drilling Project, Idaho  

NASA Astrophysics Data System (ADS)

Mineral compositions can be used to deduce magma crystallization temperatures and to infer key characteristics of magma source regions including delving into the plume or no-plume sources of intraplate basalts. To this end, mineral compositions in basalt acquired by the Snake River Scientific Drilling Project have been analyzed by electron microprobe. The samples are from the Kimama drill hole on the axis of the Central Snake River Plain, Idaho which was drilled through 1912 m of basalt and interbedded sediments. Five of the least evolved basalt flows (i.e., low Fe, Ti, and high Ni and Cr) were chosen based on semiquantitative analyses using a Bruker Tracer IV handheld X-ray fluorescence spectrometer. Phenocryst phases include olivine and plagioclase; many olivine phenocrysts also contain inclusions of Cr-Al-rich spinel. Groundmass phases are olivine, plagioclase, clinopyroxene, magnetite, and ilmenite. Olivine phenocrysts are normally zoned with cores of Fo 81-70; the rims of Fo 70-50 overlap with the compositions of olivine in the groundmass. Spinels included in olivines in the most MgO-rich lavas are Al-rich (up to 34 wt% Al2O3), similar to those in ocean island basalts (Barnes and Roeder, 2001) and some zone to higher Fe and Ti. Plagioclase phenocryst cores (An 76-65) overlap significantly with the compositions of groundmass plagioclase (An 72-40). Clinopyroxene is confined to the groundmass and creates an ophitic texture. Pyroxene compositions are typically: Wo 45-37, En 42-30, Fs 30-15 and more evolved pyroxenes trend towards Craters of the Moon pyroxenes which have lower Ca. Temperature and oxygen fugacity were calculated from magnetite-ilmenite pairs using QUILF (Anderson et al., 1993), which yielded temperatures of 750-1000°C and fO2 near or just below the QFM buffer. The magnetite-ilmenite pairs are all groundmass phases; thus, these are post-eruption temperatures and fO2 estimates. Olivine compositions were used to test if the source of the Snake River Plain basalts contains a subducted oceanic crustal component as suggested by Sobolev et al. (2005) and Herzberg (2011). The olivines in the Kimama core have Mn, Fe/Mn, and Ca concentrations that are similar to Hawaiian shield-building basalts, and are consistent with derivation of their parent magmas from pyroxenite sources, such as those hypothesized for some mantle plumes. However, Ni concentrations (500-1500 ppm) in olivines from Kimama are relatively low, and the olivines are too evolved (Fo <81) to be definitive with regard to the presence or absence of pyroxenite in the source.

Bradshaw, R. W.; Christiansen, E. H.; Dorais, M. J.; Potter, K. E.; Shervais, J. W.

2011-12-01

172

Petrology and hydrothermal mineralogy of US Geological Survey Newberry 2 drill core from Newberry Caldera, Oregon  

USGS Publications Warehouse

USGS Newberry 2 was drilled to a depth of 932 m within Newberry caldera. The bottom-hole temperature of 265??C is the highest reported temperature of any drill hole in the Cascades region of the US. The upper part of the stratigraphic section penetrated by Newberry 2 consists of caldera fill below which are increasingly more mafic lavas ranging from rhyodacite at 501 m to basalt at 932 m. Measured temperatures shallower than 300 m are less than 35??C, and rock alteration consists of hydration of glass and local palagonitization of basaltic tuffs. Incipient zeolitization and partial smectite replacement of ash and pumice occurred of basaltic tuffs. Incipient zeolitization and partial smectite replacement of ash and pumice occurred throughout the pumiceous lithic tuffs from 300 to 500 m. Higher-temperature alteration of the tuffs to chlorite and mordenite occurs adjacent to a rhyodacite sill at 460-470 m; alteration minerals within the sill consist of pyrrhotite, pyrite, quartz, calcite, and siderite. Below 697 m the rocks are progressively more altered with depth mainly because of increased temperature along a conductive gradient from 100??C at 697 m to 265??C at 930 m. -from Authors

Keith, T. E. C.; Bargar, K. E.

1988-01-01

173

Results of core drilling for uranium-bearing carbonaceous shale and lignite in the Goose Creek district, Cassia County, Idaho  

USGS Publications Warehouse

Thirteen core holes, totaling 2,023 feet, were drilled during the fall of 1953 to explore the grade and extent of uranium-bearing beds of carbonaceous shale and lignite in the east-central part of the Goose Creek district, Cassia County, Idaho. The beds tested are interbedded with volcanic ash, bentonite, greenish-gray shale, sandstone, and conglomerate in two fairly well defined zones in the lower part of the Salt Lake formation of lower Pliocene age. Nine holes penetrated carbonaceous shale beds in the Barrett zone, and one hole penetrated carbonaceous shale and lignite beds in zone B, 160 feet stratigraphically below the Barrett zone. The highest concentration of uranium found by drilling is 0.10 percent in the upper part of a 4-foot bed of carbonaceous shale and lignite in zone B. The grade of carbonaceous shale beds in the Barrett zone ranges from 0.044 percent to less than 0.003 percent uranium. Inferred reserves in the district are estimated to be 790,000 tons in beds 1 foot or more thick containing an average of 0.014 percent or 120 tons of uranium.

Mapel, William J.; Hail, William J., Jr.

1954-01-01

174

Thermal conductivity and thermal diffusivity of cores from a 26 meter deep borehole drilled in Livingston Island, Maritime Antarctic  

NASA Astrophysics Data System (ADS)

During the month of January of 2008 a borehole (Permamodel-Gulbenkian 1 — PG1) 26 m deep was drilled on the top of Mount Reina Sofia (275 m a.s.l.) near the Spanish Antarctic Station of Livingston Island, South Shetland Islands. Cores from 1.5 m to about 26 m deep were collected for measuring several physical properties. The objective of the present work is to report the values of the thermal conductivity and the thermal diffusivity that were measured in the cores from the borehole and the heat production that was estimated for the geological formations intercepted by it. Seven cores were selected to measure the thermal conductivity and the thermal diffusivity. The measured values for the thermal conductivity vary from 2.6 W/mK to 3.3 W/mK while the measured values for the thermal diffusivity vary from 1.1 × 10- 6 m2/s to 1.6 × 10- 6 m2/s. Both thermal conductivity and thermal diffusivity, on average, show a slight increase with depth. Average heat production was also estimated for two portions of the borehole: one from 2 to 12 m and the other from 12 to 25 m. A gamma-ray spectrometer was used to estimate the concentrations of uranium, thorium, and potassium of the cores, from which the heat production per unit volume was calculated. The estimated heat production for the first half of the borehole is 2.218 ?W/m3 while for the second half it is 2.173 ?W/m3; these heat production values are compatible with acidic rock types. Porosity and density were also estimated for the same cores.

Correia, A.; Vieira, G.; Ramos, M.

2012-06-01

175

Integrated Geologic, Hydrologic, and Geophysical Investigations of the Chesapeake Bay Impact Structure, Virginia, USA: A Multi-Agency Program  

NASA Technical Reports Server (NTRS)

The Chesapeake Bay impact structure is the focus of an ongoing federal-state-local research program. Recent core drilling and geophysical surveys address the formative processes and hydrogeologic properties of this major "wet-target" impact. Additional information is contained in the original extended abstract.

Gohn, G. S.; Bruce, T. S.; Catchings, R. D.; Emry, S. R.; Johnson, G. H.; Levine, J. S.; McFarland, E. R.; Poag, C. W.; Powars, D. S.

2001-01-01

176

SALTON SEA SCIENTIFIC DRILLING PROJECT: SCIENTIFIC PROGRAM.  

USGS Publications Warehouse

The Salton Sea Scientific Drilling Project, was spudded on 24 October 1985, and reached a total depth of 10,564 ft. (3. 2 km) on 17 March 1986. There followed a period of logging, a flow test, and downhole scientific measurements. The scientific goals were integrated smoothly with the engineering and economic objectives of the program and the ideal of 'science driving the drill' in continental scientific drilling projects was achieved in large measure. The principal scientific goals of the project were to study the physical and chemical processes involved in an active, magmatically driven hydrothermal system. To facilitate these studies, high priority was attached to four areas of sample and data collection, namely: (1) core and cuttings, (2) formation fluids, (3) geophysical logging, and (4) downhole physical measurements, particularly temperatures and pressures.

Sass, J. H.; Elders, W. A.

1986-01-01

177

Petrography, geochemistry, and Hf-Nd isotope evolution of drill core samples and target rocks from the El'gygytgyn impact crater, NE Chukotka, Arctic Russia  

NASA Astrophysics Data System (ADS)

El'gygytgyn in northeast Chukotka (Russia) is a 3.6 Ma, 18-km-diameter impact structure. The impact crater was recently drilled in the framework of a project sponsored by the International Continental Scientific Drilling Program (ICDP). Target rocks at the El'gygytgyn area are dominated by the felsic members of the Late Cretaceous Okhotsk-Chukotka Volcanic Belt (OCVB). Such a target lithology is unique among terrestrial impact craters, thereby providing the opportunity to study shock metamorphism in siliceous volcanic rocks. Here, we present a petrographic, geochemical, and isotopic study of the section of the drill core underneath the lacustrine sediments, extending from ˜316 m to 517 m below the lake bottom (blb). The drill core stratigraphy includes ˜80 m of suevite and a cross section through a volcanic suite, which consists of (1) a middle section (˜390-423 mblb) with dominant felsic tuffs and a few mafic members, and (2) a welded rhyolitic-dacitic ignimbrite (˜423-517 mblb). The melt fragments embedded in the suevite are interpreted as being impact-related by comparison with impact glasses from the crater and in opposition to the target rock, which does not include similar melts. A suevitic dyke crosscuts the lower section of the core at the depth 471.40 mblb. Evidence for shock metamorphism is concentrated in the upper 10 m of the drill core and almost limited to the suevitic breccia. The geochemical and isotope (Nd and Hf) composition of samples from the target and the drill core reveals relationships to the "Berlozhya magmatic assemblage" (BMA) arguing for similar source magmas. The primitive upper mantle (PUM)-normalized trace element plot of rocks investigated here confirms a subduction-related signature, as previously proposed for rocks from both OCVB and BMA.

Pittarello, Lidia; Schulz, Toni; Koeberl, Christian; Hoffmann, J. Elis; Münker, Carsten

2013-07-01

178

In-situ rock melting applied to lunar base construction and for exploration drilling and coring on the moon  

SciTech Connect

An excavation technology based upon melting of rock and soil has been extensively developed at the prototype hardware and conceptual design levels for terrestrial conditions. Laboratory and field tests of rock-melting penetration have conclusively indicated that this excavation method is insensitive to rock, soil types, and conditions. Especially significant is the ability to form in-place glass linings or casings on the walls of boreholes, tunnels, and shafts. These factors indicate the unique potential for in situ construction of primary lunar base facilities. Drilling and coring equipment for resource exploration on the moon can also be devised that are largely automated and remotely operated. It is also very likely that lunar melt-glasses will have changed mechanical properties when formed in anhydrous and hard vacuum conditions. Rock melting experiments and prototype hardware designs for lunar rock-melting excavation applications are suggested.

Rowley, J.C.; Neudecker, J.W.

1984-01-01

179

Cretaceous shallow drilling, U.S. Western Interior: Core research. Final technical report  

SciTech Connect

The primary objective of the project is to construct a subsurface transect of Cretaceous strata that were deposited in the Kansas-Colorado-Utah corridor, going from marine sequences that contain organic-carbon-rich hydrocarbon source rocks in Kansas and eastern Colorado to nearshore coal-bearing units in western Colorado and Utah. The drilling transect will provide continuous, unweathered samples for inorganic, organic, and isotopic geochemical studies and mineralogical investigations to determine the characteristics of hydrocarbon source rocks. This transect also will provide information on the extent of thermal maturation and migration of hydrocarbons in organic-carbon-rich strata along a burial gradient. In addition, the eastern Colorado hole will provide characteristics of an important fractured reservoir (the Pierre Shale) in the Florence oil field, the oldest continuously producing field in the United States (>100 years; 600 wells; >14 Mbbls).

Arthur, M.A.

1998-07-08

180

Dynamics of the late Plio-Pleistocene West Antarctic Ice Sheet documented in subglacial diamictites, AND-1B drill core  

NASA Astrophysics Data System (ADS)

Geologic studies of sediment deposited by glaciers can provide crucial insights into the subglacial environment. We studied muddy diamictites in the ANtarctic geological DRILLing (ANDRILL) AND-1B drill core, acquired from beneath the Ross Ice Shelf in McMurdo Sound, with the aim of identifying paleo-ice stream activity in the Plio-Pleistocene. Glacial advances were identified from glacial surfaces of erosion (GSEs) and subglacial diamictites within three complete sequences were investigated using lithofacies associations, micromorphology, and quartz sand grain microtextures. Whereas conditions in the Late Pliocene resemble the modern Greenland Ice Sheet where fast flowing glaciers lubricated by surface meltwater terminate directly in the sea (interval 201-212 mbsl) conditions in the Late Pleistocene are similar to modern West Antarctic Ice Sheet (WAIS) ice streams (38-49 mbsl). We identify the latter from ductile deformation and high pore-water pressure, which resulted in pervasive rotation and formation of till pellets and low relief, rounded sand grains dominated by abrasion. In the transitional period during the Mid-Pleistocene (55-68 mbsf), a slow moving inland ice sheet deposited tills with brittle deformation, producing lineations and bi-masepic and unistrial plasma fabric, along with high relief, conchoidally fractured quartz grains. Changes in the provenance of gravel to cobble-size clasts support a distant source area of Byrd Glacier for fast-flowing paleo-ice streams and a proximal area between Darwin and Skelton Glaciers for the slow-moving inland ice sheet. This difference in till provenance documents a shift in direction of glacial flow at the core site, which indirectly reflects changes in the size and thickness of the WAIS. Hence, we found that fast ice streaming motion is a consequence of a thicker WAIS pushing flow lines to the west and introducing clasts from the Byrd Glacier source area to the drill site. The detailed analysis of diamictites in AND-1B demonstrates that Pliocene glacial intervals were warmer than in the Pleistocene when polar ice sheets grew from local inland ice to regional ice streams.

Cowan, Ellen A.; Christoffersen, Poul; Powell, Ross D.; Talarico, Franco M.

2014-08-01

181

Multiple sulfur isotope characteristics of 3.46-2.7 Ga sedimentary rocks from drill cores of the Archean Biosphere Drilling Project (Invited)  

Microsoft Academic Search

As part of the Archean Biosphere Drilling Project (ABDP), we have determined the multiple sulfur isotope ratios and examined the mineralogical and geochemical characteristics of the sulfur-bearing minerals (e.g., pyrite, sphalerite, barite) and the host rocks (e.g., major and trace element chemistry; Corg, Ccarb and S contents; delta13Corg and delta13Ccarb) of >100 samples of sedimentary rocks from five ABDP drill

Y. Watanabe; H. Ohmoto

2010-01-01

182

Physical-Property Measurements on Core Samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect, North-Central Nevada.  

National Technical Information Service (NTIS)

From May to June 2008, the U.S. Geological Survey (USGS) collected and measured physical properties on 36 core samples from drill-hole Deep Blue No. 1 (DB-1) and 46 samples from drillhole Deep Blue No. 2 (DB-2) along the west side of Blue Mountain about 4...

D. A. Ponce G. Logsdon J. Casteel J. T. Watt

2009-01-01

183

Detrital dating on drill-core records from McMurdo Sound, Ross Sea (Antarctica)  

NASA Astrophysics Data System (ADS)

The influence of Antarctic ice sheets on the global climate system during the Cenozoic has been intensely investigated in the last years, especially after the successful drilling projects off-shore the western Ross Sea. While the role of the Western Ice Sheet (WAIS) during the Miocene it is not clear, the East Antarctic Ice Sheet (EAIS) has been suggested to be more or less stable and cold for the last 14 Ma. Records from drilling projects in syn-tectonic basins located on the continental shelf along the western margin of the West Antarctica Rift System (DSDP, CIROS, CRP and ANDRILL projects) may provide crucial information on the tectonic and paleo-climatic evolution of that region during Cenozoic. The drilled sedimentary records have been therefore investigated by detrital geochronology which, integrated by sandstone and gravel petrography, can provide valuable information on the dynamics of the ice sheets as provenance data are sensitive to variations in the ice-flow patterns. Apatite fission-track (AFT) data from ANDRILL and CRP records show multiple peaks in most of the samples. In the AND-2A well, whose stratigraphic record spans the last 20 Ma, the grain-age distributions are dominated by grains between 20 and 40 Ma. A young peak with a comparable age has been also episodically detected in CRP wells where conversely the most relevant population is made by grain ages between 45 and 70 Ma. Samples from Late Miocene-Pleistocene sediments of AND-1B well show a completely different AFT age distribution as a single peak is usually detected and ages are younger than 20 Ma. The AFT age range is well represented in bedrock data along the entire Transantarctic Mountains (TAM). The main denudation phase in the TAM began at 55-50 Ma but the occurrence of a young peak in the detrital data at ca. 35 Ma indicates the presence of an Oligocene pulse, as testified also by the small gap between AFT and some (U-Th-Sm)/He ages that have been detected on AND-2A samples. Such young ages are absent in the onshore portion of the TAM proximal to wells while they are present in regions located to the south. This suggests that the TAM are segmented by transversal lineaments and that significant vertical displacements occurred south of the so-called Discovery Accommodation Zone during the Oligocene. Single grain U-Pb ages on apatites from AND-2A well testify that some volcanism was concurrent with this exhumation event. The location of the volcanic centers is unknown, but aeromagnetic anomalies suggest the presence of subglacial volcanic centers beneath the Ross Ice Shelf and the WAIS. After the Oligocene, the TAM have been in a post-orogenic decay, with exhumation rates of the order of 0.1 km/Ma. As a whole, detrital ages and petrographic data agree on the idea of an ice pattern dominated by south to north trending flow lines parallel to the TAM front. Our record supports the presence of large-scale advance of WAIS across the Ross Sea. Local ice lobes from the TAM glaciers were able to transport debris only during glacial-minima settings while during periods with presence of large ice volumes, W-E flows from the TAM were obstructed by the major flow running S to N.

Zattin, M.; Andreucci, B.; Balestrieri, M.; Olivetti, V.; Pace, D.; Reiners, P. W.; Rossetti, F.; Talarico, F.; Thomson, S. N.

2012-12-01

184

Piggyback drilling in Kansas: An example for the Continental Scientific Drilling Program  

NASA Astrophysics Data System (ADS)

As the development of plate tectonic theory has provided a framework within which to interpret new geological and geophysical data, the need for an organized deep-drilling effort on the continents has become apparent. Since the expense of such a venture will be large, it is important to perform as many scientific experiments as practical on each hole drilled. This paper is a report on scientific, administrative, and financial aspects of a drilling program in Kansas. Experiences related here should be of some use to other groups planning scientific drilling ventures.Four holes were drilled to 0.5-1.1-km depth in Kansas as part of a hydrological study of the Arbuckle Formation. Two of the holes penetrated igneous rock of Precambrian age, and several meters of granitic core were recovered. At least one of the cores is highly magnetic and more radioactive than normal granite. Both cores have U/Pb zircon ages of 1340-1360 million years, presenting evidence for a previously unknown episode of intrusive activity. All four holes have been thermally logged with geothermal gradients ranging from 28° C/km to 36° C/km. The cased boreholes will be available in the future for additional experiments by other scientists.

Steeples, Donald W.; Bickford, M. E.

185

Clay-mineral assemblages from some levels of K-118 drill core of Maha Sarakham evaporites, northeastern Thailand  

NASA Astrophysics Data System (ADS)

Clay-mineral assemblages in Middle Clastic, Middle Salt, Lower Clastic, Potash Zone, and Lower Salt, totalling 13 samples from K-118 drill core, in the Maha Sarakham Formation, Khorat Basin, northeastern Thailand were studied. The clay-size particles were separated from the water-soluble salt by water leaching. Then the samples were leached again in the EDTA solution and separated into clay-size particles by using the timing sedimentation. The EDTA-clay residues were divided and analyzed by using the XRD and XRF method. The XRD peaks show that the major-clay minerals are chlorite, illite, and mixed-layer corrensite including traces of rectorite? and paragonite? The other clay-size particles are quartz and potassium feldspar. The XRF results indicate Mg-rich values and moderate Mg?Al atom ratio values in those clay minerals. The variable Fe, Na, and K contents in the clay-mineral assemblages can explain the environment of deposition compared to the positions of the samples from the core. Hypothetically, mineralogy and the chemistry of the residual assemblages strongly indicate that severe alteration and Mg-enrichment of normal clay detritus occurred in the evaporite environment through brine-sediment interaction. The various Mg-enrichment varies along the various members reflecting whether sedimentation is near or far from the hypersaline brine.

Suwanich, Parkorn

186

Magnetostratigraphy of drill-core SG-1b in the western Qaidam Basin (NE Tibetan Plateau) and tectonic implications  

NASA Astrophysics Data System (ADS)

The Qaidam Basin is an ideal archive to study long-term climate and erosion histories at the NE Tibetan Plateau. We present a magnetostratigraphic study of the 723 m deep drill-core SG-1b of lacustrine sediments at the Jianshan anticline in the western Qaidam Basin. The polarity sequence shows 18 normal and 19 reverse polarity zones which can be readily correlated with chrons C1n-C3Br of the Geomagnetic Polarity Time Scale 2004 (GPTS 2004), dating the core at about 7.3-1.6 Ma. The resulting mean sediment accumulation rate (SAR) between polarity boundaries ranges from 6.5 to 30.4 cm ka-1. High SARs occur within the intervals of >7.3-6.0, 5.2-4.2 and 3.6-2.6 Ma indicating three episodic phases of higher erosion. From the derived variation of SARs and previous results, we conclude that growth strata at the Jianshan anticline started to develop at ˜1.6 Ma by limb rotation. All this we relate to pulse tectonic uplift of the NE Tibetan Plateau and fault-propagation-folding in the Qaidam Basin.

Zhang, Weilin; Appel, Erwin; Fang, Xiaomin; Song, Chunhui; Setzer, Fabian; Herb, Christian; Yan, Maodu

2014-02-01

187

Teaching Marine Geoscience at Sea: Integrated Ocean Drilling Program's School of Rock Explores Cascadia Subduction Zone - Cores, Logs, and ACORKs  

NASA Astrophysics Data System (ADS)

For twelve days this past September, seventeen formal and informal educators from the US, UK, and France joined six instructors and a small science party on the scientific drillship JOIDES Resolution for the Integrated Ocean Drilling Program (IODP)’s Cascadia ACORK Expedition. The educators were part of the annual “School of Rock (SOR)” education program. SOR is coordinated by the U.S. Implementing Organization (USIO) of IODP and is designed to engage participants in seagoing Earth systems research and education workshops onboard the JOIDES Resolution and on shore at the Gulf Coast Core Repository in Texas. The scientific objective of the Cascadia ACORK expedition was to install a new permanent hydrologic observatory at ODP Site 889 to provide long-term monitoring of the pressure at the frontal part of the Cascadia accretionary prism. This year’s SOR workshop focused on how cores, logs, and ACORKs shed light on the hydrology and geology of the Cascadia subduction zone in the Northeast Pacific. In addition to observing the deployment of the ACORK, the SOR participants conducted daily hands-on analyses of archived sediment and hard-rock cores with scientists and technicians who specialize in IODP research using the lab facilities on the ship. Throughout the expedition, participants engaged in different activities and lessons designed to explore the deep biosphere, methane hydrates, paleoceanography, sedimentology, biostratigraphy, seafloor spreading, and drilling technology. The workshop also provided participants with “C3” time; time to communicate their experience using the successful joidesresolution.org website and other tools, make connections to their prior knowledge and expertise, and to be creative in developing and planning new education and outreach activities based on their new knowledge and research. As part of participating in the expedition, participants committed to further developing and testing their education and outreach products after the expedition, conducting post-expedition projects in conjunction with the U.S. Implementing Organization and their own institutions, and to participating actively in post-cruise evaluation. Since its inception in 2005, 75 SOR graduates and staff have conducted over 150 workshops and short courses for 3,000 participants in more than 30 U.S. states and five other nations. Integral to the success of the program is the evaluation process that takes place during and after each SOR. In particular, SOR evaluations take advantage of the power of video data collection to demonstrate the transformative nature of SOR expeditions. Video evaluations offer a unique opportunity to collect and preserve participant “voice” to document true transformative broader impacts. Along with video evaluations, the program also employs more traditional evaluation methods such as internal evaluator observations, open-ended questionnaires, and participant journals.

Reagan, M.; Collins, J.; Ludwig, K. A.; Slough, S.; Delaney, M. L.; Hovan, S. A.; Expedition 328 Scientists

2010-12-01

188

Effects of fluids on faulting within active fault zones - evidence from drill core samples recovered during the San Andreas Fault Observatory at Depth (SAFOD) drilling project  

NASA Astrophysics Data System (ADS)

Low temperature microstructures observed in samples from SAFOD drill cores indicate fluid-related deformation and chemical reactions occurring simultaneously and interacting with each other. Transmission Electron Microscopy (TEM) observations, document open pores that formed in-situ during or after deformation. In TEM images, many pores with high aspect ratio appear to be unconnected. They were possibly filled with formation water and/or hydrothermal fluids suggesting that elevated pore fluid pressure exist in the fault gouge, preventing pore collapse. The chemical influence of fluids on mineralogical alteration and geomechanical processes in fault rocks is visible in pronounced dissolution-precipitation processes (stylolites, solution seams) as well as in the formation of new phases. Detrital quartz and feldspar grains are partially dissolved and replaced by authigenic illite-smectite (I-S) mixed-layer clay minerals. TEM imaging of these grains reveals that the alteration processes initiated within pores and small intra-grain fissures. In few samples syntectonic fluid-assisted overgrowth of chlorite-rich films on slickensides partly replaced sedimentary quartz grains. Quartz and feldspar grains are partially dissolved with sutured boundaries. Newly-formed phyllosilicates are illite-smectite phases, Mg-rich smectites and chlorite minerals. They are very fine-grained (down to 20 nm) and nucleate at grain surfaces (interfaces), which in many cases are pore or fracture walls. These relatively straight or curved crystals grow into open pore spaces and fractures. They are arranged in a card-house fabric with open pore spaces between the flakes. Locally, clay flakes are bent, folded or show sigmoidal shapes indicating that they were involved in faulting. The clay particles do not show a preferred shape orientation. The predominantly random orientation distribution of the clay minerals was confirmed by x-ray synchrotron texture analysis. Pole figures show very weak textures with maxima around 1.2 m.r.d. and minima around around 0.8 m.r.d., indicating that a majority of crystals are oriented randomly. The dominance of randomly oriented clay particles, characterized by weak fabrics, may influence the mechanical stability of fault zone rocks. Formation of secondary calcite cement reveals fluid-assisted fracture healing. Cathodoluminescence microscopy shows at least three different generations of calcite veins confined to lithoclasts, displaying dissolution seams. Additionally, crack and seal processes in K-feldspar are identified. The calcite grains exhibit different degrees of deformation with evidence for twinning and crystal plasticity.

Janssen, C.; Wirth, R.; Kienast, M.; Morales, L. G.; Rybacki, E.; Wenk, H.; Dresen, G. H.

2011-12-01

189

Heterogeneous Shallow-Shelf Carbonate Buildups in the Paradox Basin, Utah and Colorado: Targets for Increased Oil Production and Reserves Using Horizontal Drilling Techniques  

SciTech Connect

This report covers research activities for the second half of the second project year (October 6, 2001, through April 5, 2002). This work includes description and analysis of cores, correlation of geophysical well logs, reservoir mapping, petrographic description of thin sections, cross plotting of permeability and porosity data, and development of horizontal drilling strategies for the Little Ute and Sleeping Ute fields in Montezuma County, Colorado. Geological characterization on a local scale focused on reservoir heterogeneity, quality, and lateral continuity, as well as possible compartmentalization, within these fields. This study utilizes representative core, geophysical logs, and thin sections to characterize and grade each field's potential for drilling horizontal laterals from existing development wells.

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

2002-07-24

190

Manson impact structure, Iowa: First geochemical results for drill core M-1  

NASA Technical Reports Server (NTRS)

The Manson Impact Structure is a large complex impact crater centered ca. S km north of the town of Manson, Iowa. It is the largest intact impact structure recognized in the United States (35 km in diameter). Its Ar-40/Ar-39 age is indistinguishable from that of the Cretaceous-Tertiary (K-T) boundary. The Manson structure may be one element of the events at the K-T boundary. The crater is completely covered by Quaternary glacial sedimentary deposits that are normally underlain by Cretaceous clastic sediments and flat-lying carbonate sediments of Phanerozoic age, as well as Proterozoic red clastic, metamorphic, volcanic, and plutonic rock sequences. The study of a reflection seismic profile, provided by Amoco, was critical in interpreting the structure. In the 35 km diameter zone that marks the extension of the crater the normal rock sequence is disturbed due to the impact, and at the center of the structure granitic basement rocks are present that have been uplifted from about 4 km depth. Our studies consist of detailed petrological and geochemical characterization of all cores, with emphasis on a detailed description of all rock types found in the core samples and their relationship to target rocks. Geochemical data on samples from the Manson M-1 core are presented.

Koeberl, Christian; Anderson, Raymond R.; Hartung, Jack B.; Reimold, Wolf Uwe

1993-01-01

191

Stratigraphy of the Hawai‘i Scientific Drilling Project core (HSDP2): Anatomy of a Hawaiian shield volcano  

Microsoft Academic Search

The Hawai‘i Scientific Drilling Project (HSDP2) successfully drilled ?3.1 km into the island of Hawai‘i. Drilling started on Mauna Loa volcano, drilling 247 m of subaerial lavas before encountering 832 m of subaerial Mauna Kea lavas, followed by 2019 m of submarine Mauna Kea volcanic and sedimentary units. The 2.85 km stratigraphic record of Mauna Kea volcano spans back to

Michael O. Garcia; Eric H. Haskins; Edward M. Stolper; Michael Baker

2007-01-01

192

Multiple sulfur isotope characteristics of 3.46-2.7 Ga sedimentary rocks from drill cores of the Archean Biosphere Drilling Project (Invited)  

NASA Astrophysics Data System (ADS)

As part of the Archean Biosphere Drilling Project (ABDP), we have determined the multiple sulfur isotope ratios and examined the mineralogical and geochemical characteristics of the sulfur-bearing minerals (e.g., pyrite, sphalerite, barite) and the host rocks (e.g., major and trace element chemistry; Corg, Ccarb and S contents; ?13Corg and ?13Ccarb) of >100 samples of sedimentary rocks from five ABDP drill cores in the Pilbara Craton, Western Australia. The total ranges of ?33S and ?34S values of the studied samples are -0.9 to +1.2‰ and -4 to +8‰, respectively. We have found that the ?33S and ?34S relationships show unique values depending on their depositional environment: (1) Pyrites in the 3.46 Ga Marble Bar Chert Member (ABDP #1), which were formed by submarine hydrothermal fluids, show no AIF-S (anomalously fractionated sulfur isotope) signatures: ?33S = -0.08 to +0.08‰ and ?34S = -3.3 to +0.6‰ (n = 5). This indicates that the H2S presented in the submarine hydrothermal fluid, which was partly generated through seawater sulfate reduction by Fe2+, did not possess AIF-S signatures. (2) Pyrites in organic C-poor lacustrine shales of the 2.76 Ga Hardey Formation (ABDP #3) also show no or very little AIF-S signatures: ?33S = -0.38 to +0.25‰ and ?34S = -2.7 to +1.9‰ (n = 18). (3) Pyrites in organic C-poor marine shales of the 2.92 Ga Mosquito Creek Formation (ABDP#5) show no or small negative AIF-S signatures: ?33S = -0.59 to 0.19 ‰ and all positive ?34S = +1.4 to +7.7‰ (n = 24). (4) Pyrites in organic C-rich (> 1 wt%) and hydrothermally altered marine shales in the 3.46 Ga Panorama Formation (ABDP #2) show constant and small positive AIF-S signatures (+0.44 to +0.61‰) and the smallest variation in ?34S (-1.1 to +1.6‰) (n = 35). In contrast, pyrites in organic C-rich shales in the 2.72 Ga Mt. Roe Basalt show negative ?33S = -0.50 to -0.10‰ and ?34S = -3.7 to 1.8‰ (n = 10). (5) Pyrites in stromatolitic carbonates of the 2.7 Ga Tumbiana Formation (ABDP #10), which deposited in shallow evaporating marine basins, possess the largest variation in AIF-S signatures among five ABDP cores: ?33S = -0.86 to 1.19‰ and ?34S = -3.2 to +1.5‰ (n = 10). (6) Compared to the negative ?33S values (-1.28 to -0.47‰) of barites in the 3.2 Ga Dresser Formation (e.g., Ueno et al., 2009), ?33S values of barites in the 3.46 Ga Panorama Formation (ABDP #2) are all positive (+0.55 to +0.61‰) and identical to those of reduced sulfur species (sphalerite and pyrite) in the same sample. The observed relationships between AIF-S signatures and depositional environments, and the abundance of samples with no AIF-S signatures, are difficult to explain by the current popular model that links AIF-S to atmospheric UV reactions. However, the data can be best explained by our model that links AIF-S to thermochemical sulfate reduction (TSR) by various solid phases and S-bearing aqueous/gaseous species (e.g., TSR by organic matter; replacement of iron oxides by pyrite) under hydrothermal conditions in a local and/or regional (basin wide) scale. Therefore, the AIF-S record of sedimentary rocks may be linked to the Earth’s thermal and biological evolution, rather than to the atmospheric evolution.

Watanabe, Y.; Ohmoto, H.

2010-12-01

193

Core drilling through the ross ice shelf (antarctica) confirmed Basal freezing.  

PubMed

New techniques that have been used to obtain a continuous ice core through the whole 416-meter thickness of the Ross Ice Shelf at Camp J-9 have demonstrated that the bottom 6 meters of the ice shelf consists of sea ice. The rate of basal freezing that is forming this ice is estimated by different methods to be 2 centimeters of ice per year. The sea ice is composed of large vertical crystals, which form the waffle-like lower boundary of the shelf. A distinct alignment of the crystals throughout the sea ice layer suggests the presence of persistent long-term currents beneath the ice shelf. PMID:17779616

Zotikov, I A; Zagorodnov, V S; Raikovsky, J V

1980-03-28

194

A chronostratigraphic framework for Neogene drill cores from McMurdo Sound, Antarctica and application to paleoclimatic and tectonic studies.  

NASA Astrophysics Data System (ADS)

New age and correlation models for Late Neogene drill cores from the McMurdo Sound Region (AND-1B, CIROS-2, and DVDP-10 and 11) have been developed using constrained optimisation, a computer assisted quantitative biostratigraphic technique. These models are used to establish ties between lithostratigraphic units and hiatuses in the cores and provide a mechanism to evaluate the regional signature of climatic variability and tectonic episodes during the Plio-Pleistocene. The models also allow us to focus on key events including warm periods and periods of increased basin subsidence. In addition these high-precision models allow us to examine the glacial-interglacial signature preserved during isochronous intervals at different locations in the basin and enable us to begin to evaluate regional response of the East and West Antarctic Ice Sheets to climate change. Several regional seismic reflectors have been mapped throughout the southern portion of the Victoria Land Basin (VLB) and are tied to the McMurdo Sound drill cores. In this study we focus on a major sequence boundary (red reflector) that forms the base of a prominent interval of clinoform sets in the southern portion of the VLB. The age of the red reflector is 4.7-4.3 Ma based on a tie to AND-1B. Although the surface cannot be tied directly to coastal margin cores (CIROS-2, and DVDP-10 and 11) our correlation models provide a framework to examine the lithostratigraphic signature of the sediments that likely encase the sequence boundary at these sites. For example, a transition from marine to terrestrial sediments is preserved in DVDP-10. This transition occurred between 4.8-4.3 Ma and indicates that the red reflector is associated with relative sea-level fall resulting from ice-sheet growth and/or tectonic uplift. Age correlative sediments preserved in AND-1B indicate regional climatic warmth, which suggests that the red reflector is more likely related to a tectonic event than significant ice volume increase. Furthermore, the onset of sediment accumulation at CIROS-2 post-dates 4.5 Ma suggesting that local subsidence and creation of accommodation space began at this time. In addition to age constraint on regional seismic reflectors, correlation models for the AND-1B and CIROS-2 cores provide an opportunity to examine sedimentation patterns across a coastal-offshore transect. Current models produce results that indicate an ‘alternating' pattern of accumulation at each site. Intervals of increased sediment accumulation at the CIROS-2 site are often tied to condensed intervals at AND-1B and vice versa. These accumulation patterns may reflect glacial-interglacial dynamics, tectonic episodes, or a combination of both. Ongoing integrated studies will focus on producing models to further examine and explain these observations.

Levy, R.; Cody, R.; Crampton, J.; Fielding, C.; Harwood, D.; Henrys, S.; Mackay, R.; Wilson, G.; Winter, D.

2009-04-01

195

Petrological and Geochemical Studies of Samples from the Nicor Chestnut 18-4 Drill Core, AMES Impact Structure, Oklahoma  

NASA Astrophysics Data System (ADS)

The near-circular 15-km-diameter Ames structure is located at 36 degrees 15' N and 98 degrees 12' W in southeastern Major County (NW Oklahoma). The structure, which is set in Cambro-Ordovician Arbuckle dolomite, consists of two concentric rims, an outer rim, which is about 1.5 to 3 km wide, and an inner "rim". The rocks of the outer rim consist mainly of fractured and brecciated Arbuckle dolomite. The inner "ring" (about 5 km in diameter) seems to be the eroded remnant of a central structural uplift, with rocks comprising brecciated Precambrian granite and Arbuckle dolomite. The depression is covered by Middle Ordovician Oil Creek shale. The structure is penetrated by a number of oil- and gas-producing wells in the crater rim and the central uplift. The production from these wells indicate that Ames represents one of the largest - if not the largest - single oil fields in Oklahoma. Currently the structural disturbance is buried beneath almost 3000 m of sedimentary rock. The origin of the structure has been intensely debated since the discovery of the structural anomaly, but geophysical and geological, as well as petrological and geochemical data provide very good evidence that it was formed by impact, and not by volcanism or even more esoteric processes. In the present study, we analyzed 17 samples, including impact melt breccia, from the Nicor Chestnut 18-4 core. These samples represent the largest and best examples of impact melt breccias and melt rock obtained so far from the Ames structure. One important result of the petrographic analyses is the observation that not all carbonate rocks postdate the impact, but some were clearly present among the target rocks. The chemical composition of the impact melt breccias is similar to that of other melt rocks from the Dorothy 1-19 core, as well as to the target granite, with variable carbonate admixtures. Some impact melt rocks are enriched in siderophile elements, indicating a possible meteoritic component.

Koeberl, C.; Reimold, W. U.

1996-03-01

196

Characterization of exposures to nanoscale particles and fibers during solid core drilling of hybrid carbon nanotube advanced composites.  

PubMed

This work investigated exposures to nanoparticles and nanofibers during solid core drilling of two types of advanced carbon nanotube (CNT)-hybrid composites: (1) reinforced plastic hybrid laminates (alumina fibers and CNT); and (2) graphite-epoxy composites (carbon fibers and CNT). Multiple real-time instruments were used to characterize the size distribution (5.6 nm to 20 microm), number and mass concentration, particle-bound polyaromatic hydrocarbons (b-PAHs), and surface area of airborne particles at the source and breathing zone. Time-integrated samples included grids for electron microscopy characterization of particle morphology and size resolved (2 nm to 20 microm) samples for the quantification of metals. Several new important findings herein include generation of airborne clusters of CNTs not seen during saw-cutting of similar composites, fewer nanofibers and respirable fibers released, similarly high exposures to nanoparticles with less dependence on the composite thickness, and ultrafine (< 5 nm) aerosol originating from thermal degradation of the composite material. PMID:21222387

Bello, Dhimiter; Wardle, Brian L; Zhang, Jie; Yamamoto, Namiko; Santeufemio, Christopher; Hallock, Marilyn; Virji, M Abbas

2010-01-01

197

Thermal Gradient and Heat Flow Drilling. Volume 5.  

National Technical Information Service (NTIS)

During the summer of 1975, the Department of Geology and Geophysics drilled nine drill thermal gradient/heat flow holes. Total footage drilled was 2125 feet. Seven holes were drilled with a Mayhew 1000 drill using various combinations of down the hole ham...

J. A. Whelan

1977-01-01

198

Geophysics in INSPIRE  

NASA Astrophysics Data System (ADS)

INSPIRE is a European directive to harmonize spatial data in Europe. Its' aim is to establish a transparent, multidisciplinary network of environmental information by using international standards and OGC web services. Spatial data themes defined in the annex of the directive cover 34 domains that are closely bundled to environment and spatial information. According to the INSPIRE roadmap all data providers must setup discovery, viewing and download services and restructure data stores to provide spatial data as defined by the underlying specifications by 2014 December 1. More than 3000 institutions are going to be involved in the progress. During the data specification process geophysics as an inevitable source of geo information was introduced to Annex II Geology. Within the Geology theme Geophysics is divided into core and extended model. The core model contains specifications for legally binding data provisioning and is going to be part of the Implementation Rules of the INSPIRE directives. To minimize the work load of obligatory data transformations the scope of the core model is very limited and simple. It covers the most essential geophysical feature types that are relevant in economic and environmental context. To fully support the use cases identified by the stake holders the extended model was developed. It contains a wide range of spatial object types for geophysical measurements, processed and interpreted results, and wrapper classes to help data providers in using the Observation and Measurements (O&M) standard for geophysical data exchange. Instead of introducing the traditional concept of "geophysical methods" at a high structural level the data model classifies measurements and geophysical models based on their spatial characteristics. Measurements are classified as geophysical station (point), geophysical profile (curve) and geophysical swath (surface). Generic classes for processing results and interpretation models are curve model (1D), surface model (2D), and solid model (3D). Both measurements and models are derived from O&M sampling features that may be linked to sampling procedures and observation results. Geophysical products are output of complex procedures and can precisely be described as chains of consecutive O&M observations. For describing geophysical processes and results the data model both supports the use of OGC standard XML encoding (SensorML, SWE, GML) and traditional industry standards (SPS, UKOOA, SEG formats). To control the scope of the model and to harmonize terminology an initial set of extendable code lists was developed. The attempt to create a hierarchical SKOS vocabulary of terms for geophysical methods, resource types, processes, properties and technical parameters was partly based on the work done in the eContentPlus GEOMIND project. The result is far from being complete, and the work must be continued in the future.

S?rés, László

2013-04-01

199

Physical properties of fault zone rocks from SAFOD: Tying logging data to high-pressure measurements on drill core  

NASA Astrophysics Data System (ADS)

In the summer of 2005, Phase 2 of the San Andreas Fault Observatory at Depth (SAFOD) borehole was completed and logged with wireline tools including a dipole sonic tool to measure P- and S-wave velocities. A zone of anomalously low velocity was detected from 3150 to 3414 m measured depth (MD), corresponding with the subsurface location of the San Andreas Fault Zone (SAFZ). This low velocity zone is 5-30% slower than the surrounding host rock. Within this broad low-velocity zone, several slip surfaces were identified as well as two actively deforming shear zones: the southwest deformation zone (SDZ) and the central deformation zone (CDZ), located at 3192 and 3302 m MD, respectively. The SAFZ had also previously been identified as a low velocity zone in seismic velocity inversion models. The anomalously low velocity was hypothesized to result from either (a) brittle deformation in the damage zone of the fault, (b) high fluid pressures with in the fault zone, or (c) lithological variation, or a combination of the above. We measured P- and S-wave velocities at ultrasonic frequencies on saturated 2.5 cm diameter core plug samples taken from SAFOD core obtained in 2007 from within the low velocity zone. The resulting values fall into two distinct groups: foliated fault gouge and non-gouge. Samples of the foliated fault gouge have P-wave velocities between 2.3-3.5 km/s while non-gouge samples lie between 4.1-5.4 km/s over a range of effective pressures from 5-70 MPa. There is a good correlation between the log measurements and laboratory values of P-and S wave velocity at in situ pressure conditions especially for the foliated fault gouge. For non-gouge samples the laboratory values are approximately 0.08-0.73 km/s faster than the log values. This difference places the non-gouge velocities within the Great Valley siltstone velocity range, as measured by logs and ultrasonic measurements performed on outcrop samples. As a high fluid pressure zone was not encountered during SAFOD drilling, we use the ultrasonic velocities of SAFOD core and analogous outcrop samples to determine if the velocity reduction is due to lithologic variations or the presence of deformational fabrics and alteration in the fault zone. Preliminary analysis indicates that while the decrease in velocity across the broad fault zone is heavily influenced by fractures, the extremely low velocities associated with the actively deforming zones are more likely caused by the development of scaly fabric with clay coatings on the fracture surfaces. Analysis of thin sections and well logs are used to support this interpretation.

Jeppson, T.; Tobin, H. J.

2013-12-01

200

The first microbiological contamination assessment by deep-sea drilling and coring by the D/V Chikyu at the Iheya North hydrothermal field in the Mid-Okinawa Trough (IODP Expedition 331)  

PubMed Central

During the Integrated Ocean Drilling Program (IODP) Expedition 331 at the Iheya North hydrothermal system in the Mid-Okinawa Trough by the D/V Chikyu, we conducted microbiological contamination tests of the drilling and coring operations. The contamination from the drilling mud fluids was assessed using both perfluorocarbon tracers (PFT) and fluorescent microsphere beads. PFT infiltration was detected from the periphery of almost all whole round cores (WRCs). By contrast, fluorescent microspheres were not detected in hydrothermally active core samples, possibly due to thermal decomposition of the microspheres under high-temperature conditions. Microbial contamination from drilling mud fluids to the core interior subsamples was further characterized by molecular-based evaluation. The microbial 16S rRNA gene phylotype compositions in the drilling mud fluids were mainly composed of sequences of Beta- and Gammaproteobacteria, and Bacteroidetes and not archaeal sequences. The phylotypes that displayed more than 97% similarity to the sequences obtained from the drilling mud fluids were defined as possible contaminants in this study and were detected as minor components of the bacterial phylotype compositions in 13 of 37 core samples. The degree of microbiological contamination was consistent with that determined by the PFT and/or microsphere assessments. This study suggests a constructive approach for evaluation and eliminating microbial contamination during riser-less drilling and coring operations by the D/V Chikyu.

Yanagawa, Katsunori; Nunoura, Takuro; McAllister, Sean M.; Hirai, Miho; Breuker, Anja; Brandt, Leah; House, Christopher H.; Moyer, Craig L.; Birrien, Jean-Louis; Aoike, Kan; Sunamura, Michinari; Urabe, Tetsuro; Mottl, Michael J.; Takai, Ken

2013-01-01

201

National Geophysical Data Center  

NSDL National Science Digital Library

The National Geophysical Data Center (NGDC), located in Boulder, Colorado is a project of the US Department of Commerce, National Oceanic & Atmospheric Administration, and National Environmental Satellite, Data and Information Service. This site is an informational resource for glaciology, marine geology and geophysics, paleoclimatology, solar-terrestrial physics, and solid earth geophysics. The glaciology section is linked to the National Snow and Ice Data Center website, which offers resources for those interested in studying snow and ice and their relation to Earth systems. The other four sections contain data (often searchable), images, reports, publications and general information on a variety of areas such as bathymetry, ocean drilling/seafloor sediment/rock sample data, the geomagnetic field, solar and upper atmospheric data, global climate, heatflow, and much more.

1997-01-01

202

Petrophysical characterization of first ever drilled core samples from an active CO2 storage site, the German Ketzin Pilot Site - Comparison with long term experiments  

NASA Astrophysics Data System (ADS)

Petrophysical properties like porosity and permeability are key parameters for a safe long-term storage of CO2 but also for the injection operation itself. These parameters may change during and/or after the CO2 injection due to geochemical reactions in the reservoir system that are triggered by the injected CO2. Here we present petrophysical data of first ever drilled cores from a newly drilled well at the active CO2 storage site - the Ketzin pilot site in the Federal State of Brandenburg, Germany. By comparison with pre-injection baseline data from core samples recovered prior to injection, the new samples provide the unique opportunity to evaluate the impact of CO2 on pore size related properties of reservoir and cap rocks at a real injection site under in-situ reservoir conditions. After injection of 61 000 tons CO2, an additional well was drilled and new rock cores were recovered. In total 100 core samples from the reservoir and the overlaying caprock were investigated by NMR relaxation. Permeability of 20 core samples was estimated by nitrogen and porosity by helium pycnometry. The determined data are comparable between pre-injection and post-injection core samples. The lower part of the reservoir sandstone is unaffected by the injected CO2. The upper part of the reservoir sandstone shows consistently slightly lower NMR porosity and permeability values in the post-injection samples when compared to the pre-injection data. This upper sandstone part is above the fluid level and CO2 present as a free gas phase and a possible residual gas saturation of the cores distorted the NMR results. The potash-containing drilling fluid can also influence these results: NMR investigation of twin samples from inner and outer parts of the cores show a reduced fraction of larger pores for the outer core samples together with lower porosities and T2 times. The drill mud penetration depth can be controlled by the added fluorescent tracer. Due to the heterogeneous character of the Stuttgart Formation it is difficult to estimate definite CO2 induced changes from petrophysical measurements. The observed changes are only minor. Several batch experiments on Ketzin samples drilled prior injection confirm the results from investigation of the in-situ rock cores. Core samples of the pre-injection wells were exposed to CO2 and brine in autoclaves over various time periods. Samples were characterized prior to and after the experiments by NMR and Mercury Injection Porosimetry (MIP). The results are consistent with the logging data and show only minor change. Unfortunately, also in these experiments observed mineralogical and petrophysical changes were within the natural heterogeneity of the Ketzin reservoir and precluded unequivocal conclusions. However, given the only minor differences between post-injection well and pre-injection well, it is reasonable to assume that the potential dissolution-precipitation processes appear to have no severe consequences on reservoir and cap rock integrity or on the injection behaviour. This is also in line with the continuously recorded injection operation parameter. These do not point to any changes in reservoir injectivity.|

Zemke, Kornelia; Liebscher, Axel

2014-05-01

203

Geophysical methods  

Microsoft Academic Search

Geophysical measurements involve no magic or mystery but straightforward applications of physical principles. This book is both a geophysical survey and a reference guide. It explains the physical principles involved in geophysical methods. Over one-third of the text is devoted to seismic methods. Comprehensive topics in the volume include: the measurement of different physical properties and their geological significance; how

1989-01-01

204

Drill, Baby, Drill  

ERIC Educational Resources Information Center

School fire drills are quickly becoming insignificant and inconvenient to school administrators. When the time for the monthly fire drill rolls around, it is often performed with a "let's get this over with" attitude. Although all schools conduct fire drills, seldom do they effectively train students and staff members how to respond in a real…

Kerkhoff, Todd

2009-01-01

205

Summary of micrographic analysis of fracture coating phases on drill cores from Pahute Mesa, Nevada Test Site. Revision 1  

SciTech Connect

The flow path between Pahute Mesa and the groundwater discharge area in Oasis Valley (approximately 18 miles to the southwest) is of concern due to the relatively short travel distance between a recharge area where underground nuclear testing has been conducted and the off-site water users. Groundwater flow and transport modeling by IT Corporation (IT) has shown rapid tritium transport in the volcanic rock aquifers along this flow path. The resultant estimates of rapid transport were based on water level data, limited hydraulic conductivity data, estimates of groundwater discharge rates in Oasis Valley, assumed porosities, and estimated retardation rates. Many of these parameters are poorly constrained and may vary considerably. Sampling and analytical techniques are being applied as an independent means to determine transport rates by providing an understanding of the geochemical processes that control solute movement along the flow path. As part of these geochemical investigations, this report summarizes the analysis of fracture coating mineral phases from drill core samples from the Pahute mesa area of the Nevada Test Site (NTS). Archived samples were collected based on the presence of natural fractures and on the types and abundance of secondary mineral phases present on those fracture surfaces. Mineral phases present along fracture surfaces are significant because, through the process of water-rock interaction, they can either contribute (as a result of dissolution) or remove (as a result of precipitation or adsorption) constituents from solution. Particular attention was paid to secondary calcite occurrences because they represent a potential source of exchangeable carbon and can interact with groundwater resulting in a modified isotopic signature and apparent water age.

NONE

1998-12-01

206

HYDRATE CORE DRILLING TESTS  

Microsoft Academic Search

The ''Methane Hydrate Production from Alaskan Permafrost'' project is a three-year endeavor being conducted by Maurer Technology Inc. (MTI), Noble, and Anadarko Petroleum, in partnership with the U.S. DOE National Energy Technology Laboratory (NETL). The project's goal is to build on previous and ongoing R&D in the area of onshore hydrate deposition. The project team plans to design and implement

John H. Cohen; Thomas E. Williams; Ali G. Kadaster; Bill V. Liddell

2002-01-01

207

Paleogene and Cretaceous sediment cores from the Kilwa and Lindi areas of coastal Tanzania: Tanzania Drilling Project Sites 1-5  

NASA Astrophysics Data System (ADS)

Initial results of scientific drilling in southern coastal Tanzania are described. A total of five sites was drilled (mostly using continuous coring) by the Tanzania Drilling Project for paleoclimate studies. The sediments are predominantly clays and claystones deposited in a deep marine shelf environment and often contain excellently preserved microfossils suitable for geochemical analysis. The studies reported here include summaries of the lithostratigraphy, biostratigraphy (planktonic foraminifers, calcareous nannofossils, benthic foraminifers, and palynology), magnetostratigraphy, and organic geochemistry. TDP Site 1 was drilled near Kilwa Masoko airstrip (8°54.516 'S, 39°30.397 'E). It yielded 8.55 m of barren blue-grey clays that may be Miocene in age, followed by 1.2 m of greenish-black to dark greenish-grey clay probably of the same age. The remainder of the hole cored 62.35 m of lower Oligocene sediments (nannofossil Zone NP23), which are predominantly greenish-black to dark greenish-grey clays. Total penetration was 74.10 m. The coring represents the first report of a thick Oligocene clay formation in the area. TDP Site 2 was drilled near Kilwa Masoko prison (8°55.277 'S, 39°30.219 'E). It yielded 92.78 m of predominantly dark greenish-grey clay with occasional allochthonous limestone beds that consist mostly of redeposited larger foraminifers. The site encompasses lower to middle Eocene planktonic foraminifer Zones P8/9 to P11 and nannofossil Subzones NP14b to NP15c. It encompasses a rarely cored interval across the Ypresian-Lutetian transition. TDP Site 3 was drilled near Mpara in the Kilwa area (8°51.585 'S, 39°27.655 'E). It yielded 56.4 m of predominantly dark greenish-grey clays and claystones. The site is assigned to lower Eocene planktonic foraminifer Zone P6 and nannofossil Zone NP11. TDP Site 4 was drilled near Ras Tipuli on the northwest side of Lindi creek (9°56.999 'S, 39°42.985 'E). It yielded 19.8 m of predominantly dark greenish-grey clay with allochthonous limestone interbeds. The site encompasses middle Eocene planktonic foraminifer Zones P12-P14 and nannofossil Zone NP17. TDP Site 5 was drilled at Machole, near Lindi, south of Kitulo Hill (10°01.646 'S, 39°41.375 'E). It yielded 31.6 m of predominantly greenish-black to dark greenish-grey clay assigned to the upper Cretaceous Globotruncana falsostuarti planktonic foraminifer zone and nannofossil zones UC15e-UC17 (upper Campanian-lower Maastrichtian). Paleomagnetic analysis suggests that the site straddles two magnetic reversals, between Chrons C32r.2r and C32r.1n. Samples from TDP Sites 1-5 yielded dinocyst and miospore assemblages that are integrated with the calcareous stratigraphy. Organic geochemical analyses of samples from each of the cores revealed biomarkers of predominantly terrestrial origin and an unusually low degree of thermal maturity, suggesting shallow burial depths. X-ray diffraction studies suggest that much of the Paleogene clay may be reworked from eroded Mesozoic formations.

Pearson, Paul N.; Nicholas, Christopher J.; Singano, Joyce M.; Bown, Paul R.; Coxall, Helen K.; van Dongen, Bart E.; Huber, Brian T.; Karega, Amina; Lees, Jackie A.; Msaky, Emma; Pancost, Richard D.; Pearson, Marion; Roberts, Andrew P.

2004-05-01

208

Subsurface structure, physical properties, fault-zone characteristics and stress state in scientific drill holes of Taiwan Chelungpu Fault Drilling Project  

Microsoft Academic Search

Continuous cores and a suit of geophysical measurements were collected in two scientific drill holes to understand physical mechanisms involved in the large displacements during the 1999 Chi-Chi earthquake. Physical properties obtained from wire-line logs including P- and S-wave sonic velocity, gamma ray, electrical resistivity, density and temperature, are primarily dependent on parameters such as lithology, depth and fault zones.

Jih-Hao Hung; Kuo-Fong Ma; Chien-Yin Wang; Hisao Ito; Weiren Lin; En-Chao Yeh

2009-01-01

209

Melt layer statistic of two firn cores recently drilled at Dye3 and South dome in the dry snow zone of Southern Greenland  

NASA Astrophysics Data System (ADS)

In the last couple of years remote sensing data have shown large areas of wet snow in the Southern part of the Greenland ice sheet. These melt features are attributed to the overall warming trend. Persistent warming implies changes in the firn layer as well. Even in areas of the dry snow zone one can observe sporadically a few ice lenses within the firn column indicating refrozen meltwater from warm events in the past. In our contribution we want to close the gap between investigations of firn cores drilled in the 70's and the observational record of remote sensing data over the last decade in South Greenland. The focus lies on firn of the dry snow zone which is sensitive against changes in a warming atmosphere and cold enough to prevent a longway percolation path of meltwater to several firn layers. To this end we had drilled two 45m-long firn cores at the former drilling sites of DYE3 (65°11'N, 43°49'W) and South Dome (SD) (63°32'N, 44°34'W) during a aircraft-supported field campaign 2012. The retrieved 3inch-firn core segments of 1m length are measured by a X-ray-scanning routine with the means of the core-scale AWI-ICE-CT. The 2d-density fields are calculated and allow to distinguish between refreezing meltwater and compacted firn. The depth-scales are converted to time-scales by using DEP (dielectric profiling) and (in case of DYE3) discrete sampled d18O measurements. Number density of melt layers and relative amount of melt show an synchronized behavior with an general increase over the last 30 years. Local maxima are observed in both sites at around 6-9m and 25m at DYE3 and 5-8m, 22m and 40m at SD.

Freitag, Johannes; Kipfstsuhl, Sepp; Hoerz, Sebastian; Eling, Lukas; Vinther, Bo; Popp, Trevor

2014-05-01

210

Oceanic Core Complexes and Crustal Accretion at Slow-Spreading Ridges. Indications From IODP Expeditions 304-305 and Previous Ocean Drilling Results  

NASA Astrophysics Data System (ADS)

Oceanic core complexes expose intrusive crustal rocks on the seafloor via detachment faulting and are often associated with significant extents of serpentinized mantle peridotite at the seafloor. These serpentinite units have unknown thickness in most cases. Assuming that steep slopes surrounding the domal core provide a cross section, one would infer they comprise much of the section for depths of at least several hundred meters. IODP expeditions 304-305 results at the Mid-Atlantic Ridge 30°N (Atlantis Massif), taken together with recent results from seafloor mapping and ODP drilling in the Atlantic as well as on the SWIR, suggest that a revised model of oceanic core complex (OCC) development should be considered. All of the ODP/IODP drilling at 4 different core complexes and/or inside corner highs so far have recovered only gabbroic sections, with almost no serpentinized peridotite. Here we explore aspects of a possible revised model for oceanic core complex development in which the "core" of these structural complexes represents a period of greater than typical mafic intrusion in overall magma-poor regions of slow and ultra-slow spreading ridges. Exposure of the gabbroic intrusion(s) is enabled by deformation that localized predominantly within the serpentinized peridotite that initially surrounded them. The development of a detachment fault system on the central dome of Atlantis massif may have occurred relatively late in its evolution, controlling the exposure along a domal high via mostly brittle faulting. The proposed model is different from previous published models in that OCC represent the tectonic and morphoplogic expression of the magma-rich end-member of a fundamental mode of crustal accretion- the intrusion of gabbro plutons at depth. The model resembles a system of ball-bearings, in which episodically some gabbroic "balls" are larger. It does not necessarily imply that the detachment fault capping OCC is a single, deep-rooting fault. The geometry of the fault system may vary on a case-by-case basis, depending on the volume of gabbro present beneath the axis and on its crystallization depth. The model implies that serpentinized fault zones envelop the gabbro intrusions, thus explaining the paradox of dominantly gabbroic cores in the vicinity of seafloor serpentinites on top or on the flanks of OCC. We predict that dominant serpentinites on the southern wall of Atlantis massif may form a relatively thin sheath on the terminus of a dominantly gabbroic core. Further work (e.g., deep drilling on the southern ridge) is required to determine if this working model is correct since current data are equivocal.

Ildefonse, B.; Blackman, D. K.; John, B. E.; Ohara, Y.; Miller, D. J.; MacLeod, C. J.; Iodp Expeditions 304/305 Science Party

2006-12-01

211

Crystallization history of Kilauea Iki lava lake as seen in drill core recovered in 1967-1979  

USGS Publications Warehouse

Kilauea Iki lava lake formed during the 1959 summit eruption, one of the most picritic eruptions of Kilauea Volcano in the twentieth century. Since 1959 the 110 to 122 m thick lake has cooled slowly, developing steadily thickening upper and lower crusts, with a lens of more molten lava in between. Recent coring dates, with maximum depths reached in the center of the lake, are: 1967 (26.5 m). 1975 (44.2 m), 1976 (46.0 m) and 1979 (52.7 m). These depths define the base of the upper crust at the time of drilling. The bulk of the core consists of a gray, olivine-phyric basalt matrix, which locally contains coarser-grained diabasic segregation veins. The most important megascopic variation in the matrix rock is its variation in olivine content. The upper 15 m of crust is very olivine-rich. Abundance and average size of olivine decrease irregularly downward to 23 m; between 23 and 40 m the rock contains 5-10% of small olivine phenocrysts. Below 40 m. olivine content and average grainsize rise sharply. Olivine contents remain high (20-45%, by volume) throughout the lower crust, except for a narrow (< 6 m) olivine depleted zone near the basalt contact. Petrographically the olivine phenocrysts in Kilauea Iki can be divided into two types. Type 1 phenocrysts are large (1-12 mm long), with irregular blocky outlines, and often contain kink bands. Type 2 crystals are relatively small (0.5-2 mm in length), euhedral and undeformed. The variations in olivine content of the matrix rock are almost entirely variations in the amount of type 1 olivines. Sharp mineral layering of any sort is rare in Kilauea Iki. However, the depth range 41-52 m is marked by the frequent occurrence of steeply dipping (70??-90??) bands or bodies of slightly vuggy olivine-rich rock locally capped with a small cupola of segregation-vein material. In thin section there is clear evidence for relative movement of melt and crystals within these structures. The segregation veins occur only in the upper crust. The most widely distributed (occurring from 4.5-59.4 m) are thin veins (most < 5 cm thick), which cut the core at moderate angles and appear to have been derived from the immediately adjacent wall-rock by filter pressing. There is also a series of thicker (0.1-1.5 m) segregation veins, which recur every 2-3 m, between 20 and 52 m. These have subhorizontal contacts and appear, from similarities in thickness and spacing, to correlate between drill holes as much as 100 m apart. These large veins are not derived from the adjacent wallrock: their mechanism of formation is still problematical. The total thickness of segregation veins in Kilauea Iki is 3-6 m in the central part of the lake, corresponding to 6-11% of the upper crust. Whole-rock compositions for Kilauea Iki fall into two groups: the matrix rock ranges from 20-7.5% MgO, while the segregation veins all contain between 6.0 and 4.5% MgO. There are no whole-rock compositions of intermediate MgO content. Samples from < 12 m show eruption-controlled chemistry. Below that depth, matrix rock compositions have higher Al2O3, TiO2 and alkalies, and lower CaO and FeO, at a given MgO content than do the eruption pumices. The probable causes of this are assimilation of low-melting components from foundered crust, plus removal of olivine, plus removal of minor augite, for rocks with MgO contents of < 8.0%. Given the observed rate of growth of the upper crust, one can infer that significant removal of the type 1 olivine phenocrysts from the upper part of the lake began in 1963 and ceased sometime prior to 1972. The process. probably gravitative settling, appears to have been inhibited earlier by gas streaming from the lower part of the lens of melt. The olivine cumulate zone, which extends into the upper crust, contains relatively few (25-40%) olivine crystals, few of which actually touch each other. The diffuseness of the cumulate zone raises the possibility that the crystals were coated with a relatively visous boundary layer

Helz, R. T.

1980-01-01

212

Ages and stable-isotope compositions of secondary calcite and opal in drill cores from Tertiary volcanic rocks of the Yucca Mountain area, Nevada  

USGS Publications Warehouse

Stable-isotope compositions of fracture- and cavity-filling calcite from the unsaturated zone of three drill cores at Yucca Mountain Tertiary volcanic complex indicate that the water from which the minerals precipitated was probably meteoric in origin. A decrease in 18O in the calcite with depth is interpreted as being due to the increase in temperature in drill holes corresponding to an estimated average geothermal gradient of 34?? per kilometer. A few of the calcite samples and all of the opal samples yielded uranium-series ages older than 400 000 yr, although most of the calcite samples yielded ages between 26 000 and 310 000 yr. The stable-isotope and uranium-series dates from precipitated calcite and opal of this reconnaissance study suggest a complex history of fluid movement through the volcanic pile, and episodes of fracture filling predominantly from meteoric water during at least the past 400 000 yr. -Authors

Szabo, B. J.; Kyser, T. K.

1990-01-01

213

U-Th and ESR dating of drilled cores from a giant hydrothermal mounds in South Mariana  

NASA Astrophysics Data System (ADS)

The time scale for hydrothermal activity is an important factor controlling the size of hydrothermal ore deposits and the evolution of chemosynthesis-based communities in a submarine hydrothermal system. We determined the age of hydrothermal deposits samples, both collected samples by submersible and drilled core samples from South Mariana Trough. Samples were collected from four hydrothermal sites, Snail (near the spreading axis), Archean ( 1.5km from the axis), Pika ( 4.9km from the axis) and Urashima ( 4.9km from the axis). 230Th-234U radioactive disequilibrium dating was applied to hydrothermal sufide minerals consisting of pyrite and sphalerite while electron spin resonance (ESR) dating was applied to barite. For 230Th-234U radioactive disequilibrium dating, we carried out magnetic separation for bulk samples, then we digested samples with nitric acid. U and Th were purified by two-step column separations, and isotopic compositions of spiked and unspiked U and Th were measured by a MC-ICP-MS. Analytical methods for ESR age determination were described in a companion abstract by Toyoda et al. We found that the magnetic fractions had significantly higher U/Th ratios, which enabled 230Th-234U age determinations as precise as ±2% (2?). This probably reflects that pyrite enriched in magnetic fractions has high U/Th ration. In a sulfide crust sample collected from Archean site, the 230Th-234U ages of the sulfide minerals (0.3-2.2 ka) were compared with ESR ages of barites separated from 12 subsamples of the same sulfide crust. ESR ages (0.27 - 1.7 ka) show a spatial pattern broadly resembling that observed in 230Th-234U dating method. While there are some significant offsets, these results illustrate the potential of the two methods for use in provide information on evolution history of a hydrothermal system. Samples from Pika, Archean and Snail sites yield from 0.5 to ~9 ka, from 0.1 to 3 ka and < ~90 a, respectively. The oldest ages from each site are correlated with the distance from spreading axis.

Takamasa, A.; Nakai, S.; Sato, F.; Toyoda, S.; Ishibashi, J.

2012-12-01

214

Predicting Sediment Strength in Accretionary Complexes Using Geophysical Logs  

NASA Astrophysics Data System (ADS)

A new approach has been taken to predict undrained shear strength of fine grained sediment and soft rock from geophysical logs and core measurements using neural networks. A limited number of undrained shear strength measurements are performed on scientific ocean drilling sediment cores, resulting in a limited, discontinuous data set. A series of neural networks were developed to predict the undrained shear strength of sediments over intervals where strength was not directly measured. The prediction is based on a learned relationship between the suite of downhole geophysical logs and the measurements of undrained shear strength. The use of neural networks to predict shear strength in cores requires that a statistically significant number of shear strength measurements are available to train and test the neural network. Geophysical logs are necessary to develop a relationship with the shear strength measurements. The approach was developed using shear strength data measured on sediment core samples from Ocean Drilling Program (ODP) Leg 162 in intervals ranging from 15 cm to greater than 200 cm. The neural network was able to resolve the shear strength measurements to a depth resolution of approximately 20 cm. The trained neural network was then used to predict the undrained shear strength in an additional borehole that was not used in training the neural network. The predicted shear strength values, when compared with actual shear strength measurements, show good correlation. This proven technique was then applied to the Nankai Trough accretionary prism using data from ODP Legs 131, 190, and 196, resulting in a high depth resolution prediction of shear strength at the deformation front of the prism. The shear strength predictions through the accretionary prism are important when determining the deformation history of the prism. The deformation history controls the fluid flow of the system through the development of faults.

Paulson, M.; Merrill, J.; Moran, K.; Baxter, C.; Ressler, J.

2006-12-01

215

Ocean Drilling Program  

NSDL National Science Digital Library

This site describes the Ocean Drilling Program (ODP). The ODP conducts basic research into the history of the ocean basins and the overall nature of the crust beneath the ocean floor using the scientific drill ship JOIDES Resolution. There are also links to photographs, core data, and educational material on the site.

Program, Ocean D.; Texas A&M University

216

Lunar deep drill apparatus  

NASA Technical Reports Server (NTRS)

A self contained, mobile drilling and coring system was designed to operate on the Lunar surface and be controlled remotely from earth. The system uses SKITTER (Spatial Kinematic Inertial Translatory Tripod Extremity Robot) as its foundation and produces Lunar core samples two meters long and fifty millimeters in diameter. The drill bit used for this is composed of 30 per carat diamonds in a sintered tungsten carbide matrix. To drill up to 50 m depths, the bit assembly will be attached to a drill string made from 2 m rods which will be carried in racks on SKITTER. Rotary power for drilling will be supplied by a Curvo-Synchronous motor. SKITTER is to support this system through a hexagonal shaped structure which will contain the drill motor and the power supply. A micro-coring drill will be used to remove a preliminary sample 5 mm in diameter and 20 mm long from the side of the core. This whole system is to be controlled from earth. This is carried out by a continuously monitoring PLC onboard the drill rig. A touch screen control console allows the operator on earth to monitor the progress of the operation and intervene if necessary.

Harvey, Jill (editor)

1989-01-01

217

Sedimentary dynamics on isolated highs in Lake Baikal: evidence from detailed high-resolution geophysical data and sediment cores  

Microsoft Academic Search

High- and very-high-resolution seismic data, side-scan sonar mosaics and piston cores from three isolated highs in Lake Baikal (Vydrino Shoulder, Posolsky Bank, Continent Ridge) have allowed to document in unprecedented detail the depositional, re-depositional and tectonic processes and to characterise the overal sedimentary environment on such isolated highs. Our data show that Vydrino Shoulder actually represents a turbidity- or underflow-sourced

F. Charlet; N. Fagel; M. De Batist; F. Hauregard; B. Minnebo; D. Meischner; SONIC Teamd

2005-01-01

218

Geochemical and Diatom Records of Hydrologic Variability in the Tropical Andes During the Late Quaternary From Drill Cores of Lake Titicaca  

NASA Astrophysics Data System (ADS)

Seven drill cores were recovered from Lake Titicaca during the NSF/ICDP/DOSECC drilling expedition of 2001. Sub-lake floor drilling depths ranged from 53 to 139 m; water depths ranged from 40 to 232 m; recoveries ranged from 75 to 112%. Our most detailed multi-proxy analyses to date have been done on Core 2B raised from the central basin of the lake from 232 m water depth, drilled to 139.26 m sub-lakefloor with 140.61 m of total sediment recovered (101%). A basal age of 200 Ka is estimated by linear extrapolation from radiocarbon measurements in the upper 25 m of core; Ar-Ar dating of interbedded ashes is underway. The volume and lake level of Lake Titicaca have undergone large changes several times during the late Quaternary. Proxies for these water level changes (each of different fidelity) include the ratio of planktonic-to-benthic diatoms, sedimentary carbonate content, and stable isotopic content of organic carbon. The most recent of these changes, have been described previously from earlier piston cores. In the early and middle Holocene the lake fell below its outlet to 85 m below modern level, lake salinity increased several times, and the Salar de Uyuni, which receives overflow from Titicaca, dessicated. In contrast, Lake Titicaca was deep, fresh, and overflowing (southward to the Salar de Uyuni) throughout the last glacial maximum from prior to 25,000 BP to at least 15,000 BP. According to our extrapolated ages, the penultimate major lowstand of Lake Titicaca occurred around 75,000 to 80,000 BP, when seismic evidence indicates that lake level was about 240 m lower than present. Near the end of this lowstand, the lake also became quite saline. There are at least three, and possibly more, older lowstands, each separated temporally by periods in which the lake freshened dramatically and overflowed. Our analyses include decadal resolution of the stable isotopic composition of lowstand carbonate sediments. Taking advantage of a quantitative relationship between precipitation amount and ?18O of the precipitation, we use model calculations and the observed oxygen isotopic record to reconstruct precipitation rates during the carbonate-bearing intervals. These are compared with similar analyses and calculations done on the highstand deposits in the Salar de Uyuni (contemporaneous deposits in Lake Titicaca contain no carbonate).

Baker, P. A.; Fritz, S. C.; Seltzer, G. O.; Arnold, K. K.; Tapia, P. M.

2002-12-01

219

Kilauea iki lava lake: geophysical constraints on its present (1980) physical state  

NASA Astrophysics Data System (ADS)

A model is presented representing the present-day (1980) configuration of Kilauea Iki lava lake. This interpretation is a synthesis of the results of drilling, thermal modelling, petrology and geophysical sensing experiments. According to this model, the crust of the lava lake is characterized by a thick two-phase convection-dominated zone and a singlephase (steam) dry-out zone. Geophysical measurements (namely electromagnetic sounding experiments) suggest the presence of an anomalous zone which is significantly thicker (more than 30 m thick at 40 m depth) than the zone of melt-slush (10 m thick at 54 m depth seen in petrological investigations of the drill core. This suggests that the geophysically active zone is caused by physical processes not directly related to the presence of magma or that the magma is thinly disseminated over a broader region than indicated in petrological inspections of recent (1979) drill cores. We cannot at this time rule out (or support) the possibility of a plexus of segregation veins distributed throughout the hightemperature region of the lake, particularly below the melt-slush region where information is sparse.

Hermance, John F.; Colp, John L.

1982-07-01

220

Quaternary evolution of the delta systems and the coast line of Lake Ohrid (FYROM/Albania) revealed by shallow geophysical and drilling data  

NASA Astrophysics Data System (ADS)

The Lake Ohrid Basin (40°54´ - 41°10`N, 20°38`- 20°48`E) is a cross boundary lake (FYROM/Albania) stretching over a length of c. 30 km and a width of c. 15 km. It is situated in a karstic environment in the Balkanides, an active tectonic region. The general geodynamic setting of the Lake Ohrid area can be described as a "basin and range" situation which is influenced by the northern part of the Hellenic trench and is underlain by ongonig extension so that the Ohrid basin is still actively subsiding. Typical sedimentation patterns supported by the topography give evidence for a tectonically controlled regime. Inactive, Pleistocene lobe-shaped fans are cut off relatively linear by the lake. Drowned alluvial fans along the west coast give evidence for lake-level fluctuations or tectonic subsidence along the western basin margin. In contrast the Struga plain in the North is a vast dried up area, which acts either as a sedimentary catchment for a fan system or as a tectonic basement which is subject to subsidence. Thus, the investigation areas concentrated close to the shorelines including extensive parts at the west coast, in the Struga Plain to the North, the deltas of the inflowing rivers and mass movement bodies at the east coast. Ground Penetrating Radar and Electric Resistivity have been applied, as a non-invasive shallow subsurface mapping methods, to image the sedimentary and tectonic structures. Sediment cores were taken and grain size and sediment composition were analysed. In the aggradation and deltaic plains of the Dajan river in the north and of the Cerava river in the south sets of channels cutting into horizontal layers were identified close to the shoreline. Several S-ward dipping foreset-like structures were found in the north near Struga. The cores show sequences of grain sizes varying between clay and gravel intersected by intervals that are fining upward, and are interpreted as fluvial sediments. No evidences for a higher lake-level were found, such as fine-grained limnic sediments, organic material or shells in the cores. In conclusion, during the Pleistocene higher erosion rates are observed around Lake Ohrid, but no evidence for higher lake-level was found in the plains north and south of the lake. Thus the Pleistocene sediments are affected by erosion and by fault activity, mainly along N-S striking normal faults. Flooding of the Struga plain is only subject to a lower ground level presuming that the old shorelines where limited by the deposits of the fans.

Hoffmann, Nadine; Reicherter, Klaus; Gruetzner, Christoph

2010-05-01

221

Use of seismic data can cut Arctic drilling costs  

Microsoft Academic Search

In the frontier drilling areas, geophysical data are important tools in planning drilling programs since information from offset wells is seldom available. By using seismic interval velocity profiles, Gulf Oil Canada has been able to predict troublesome drilling areas and abnormally high pressures in addition to reducing drilling costs through better utilization of bits and casing.

A. E. Dumont; V. S. Purdy

1976-01-01

222

Structure in continuously cored, deep drill holes at Yucca Mountain, Nevada, with notes on calcite occurrence; Yucca Mountain Site Characterization Project  

SciTech Connect

A study of more than 22,000 feet of core from five deep drill holes at Yucca Mountain, Nevada, provided data on the attitude and vertical distribution of faults and fractures, the sense of fault displacement, and the occurrence of calcite. The study was done mainly to look for evidence of fault flattening at depth, but no consistent downward decrease in dip of faults was found, and no increase in strata rotation was evident with increasing depth. In the two drill holes located near prominent faults that dip toward the holes (USW G-3 and G-2), an apparent increase in the frequency of faults occurs below the tuffs and lavas of Calico Hills. Some of this increase occurs in brittle lavas and flow breccias in the lower part of the volcanic section. In the two holes presumed to be relatively removed from the influence of important faults at depth, the vertical distribution of faults is relatively uniform. Calcite occurs mainly in two general zones, voids in welded portions of the Paintbrush Tuff, and in a deeper zone, mostly below 3,500 feet. Calcite is least abundant in USW G-4, which may reflect the fewer faults and fractures encountered in that drill hole.

Carr, W.J. [Carr (Wilfred J.), Wheat Ridge, CO (United States)

1992-12-01

223

Polar organic compounds in pore waters of the Chesapeake Bay impact structure, Eyreville core hole: Character of the dissolved organic carbon and comparison with drilling fluids  

USGS Publications Warehouse

Pore waters from the Chesapeake Bay impact structure cores recovered at Eyreville Farm, Northampton County, Virginia, were analyzed to characterize the dissolved organic carbon. After squeezing or centrifuging, a small volume of pore water, 100 ??L, was taken for analysis by electrospray ionization-mass spectrometry. Porewater samples were analyzed directly without filtration or fractionation, in positive and negative mode, for polar organic compounds. Spectra in both modes were dominated by low-molecular-weight ions. Negative mode had clusters of ions differing by -60 daltons, possibly due to increasing concentrations of inorganic salts. The numberaverage molecular weight and weight-average molecular weight values for the pore waters from the Chesapeake Bay impact structure are higher than those reported for other aquatic sources of natural dissolved organic carbon as determined by electrospray ionization-mass spectrometry. In order to address the question of whether drilling mud fluids may have contaminated the pore waters during sample collection, spectra from the pore waters were compared to spectra from drilling mud fluids. Ions indicative of drilling mud fluids were not found in spectra from the pore waters, indicating there was no detectable contamination, and highlighting the usefulness of this analytical technique for detecting potential contamination during sample collection. ?? 2009 The Geological Society of America.

Rostad, C. E.; Sanford, W. E.

2009-01-01

224

Chemical geodynamics of continental subduction-zone metamorphism: Insights from studies of the Chinese Continental Scientific Drilling (CCSD) core samples  

NASA Astrophysics Data System (ADS)

The Dabie-Sulu orogenic belt of east-central China has long been a type location for the study of geodynamic processes associated with ultrahigh-pressure (UHP) tectonics. Much of our understanding of the world's most enigmatic processes in continental deep-subduction zones has been deduced from various records in this belt. By taking advantage of having depth profiles from core samples of the Chinese Continental Scientific Drilling (CCSD) project in the Sulu orogen, a series of combined studies were carried out for UHP metamorphic rocks from the main hole (MH) at continuous depths of 100 to 5000 m. The results provide new insights into the chemical geodynamics of continental subduction-zone metamorphism, especially on the issues that are not able to be resolved from the surface outcrops. Available results from our geochemical studies of CCSD-MH core samples can be outlined as follows. (1) An O isotope profile of 100 to 5000 m is established for the UHP metamorphic minerals, with finding of 18O depletion as deep as 3300 m. Along with areal 18O depletion of over 30,000 km 2 along the Dabie-Sulu orogenic belt, three-dimensional 18O depletion of over 100,000 km 3 occurs along the northern margin of the South China Block. (2) Changes in mineral O isotope, H isotope and water content occur in eclogite-gneiss transitions, concordant with petrographic changes. The contact between different lithologies is thus the most favorable place for fluid action; fluid for retrogression of the eclogites away from the eclogite-gneiss boundary was derived from the decompression exsolution. For the eclogites adjacent to gneiss, in contrast, the retrograde metamorphism was principally caused by aqueous fluid from the gneiss that is relatively rich in water. Inspection of the relationship between the distance, petrography and ?18O values of adjacent samples shows O isotope heterogeneities between the different and same lithologies on scales of 20 to 50 cm, corresponding to the maximum scales of fluid mobility during the continental collision. (3) Studies of major and trace elements in the two continuous core segments indicate high mobility of LILE and LREE but immobility of HFSE and HREE. Some eclogites have andesitic compositions with high SiO 2, alkalis, LREE and LILE but low CaO, MgO and FeO contents. These features likely result from chemical exchange with gneisses, possibly due to the metasomatism of felsic melt produced by partial melting of the associated gneisses during the exhumation. On the other hand, some eclogites appear to have geochemical affinity to refractory rocks formed by melt extraction as evidence by strong LREE and LILE depletion and the absence of hydrous minerals. These results provide evidence for melt-induced element mobility in the UHP metamorphic rocks, and thus the possible presence of supercritical fluid during exhumation. In particular, large variations in the abundance of such elements as SiO 2, LREE and LILE occur at the contact between eclogite and gneiss. This indicates their mobility between different slab components, although it only occurs on small scales and is thus limited in local open-systems. (4) Despite the widespread retrogression, retrograde fluid was internally buffered in stable isotope compositions, and the retrograde fluid was of deuteric origin and thus was derived from the decompression exsolution of structural hydroxyl and molecular water in nominally anhydrous minerals. (5) A combined study of petrography and geochronology reveals the episode of HP eclogite-facies recrystallization at 216 ± 3 Ma, with timescale of 1.9 to 9.3 Myr or less. Collectively, the Dabie-Sulu UHP terrenes underwent the protracted exhumation (2-3 mm/yr) in the HP-UHP regime. (6) Zircon U-Pb ages and Hf isotopes indicate that mid-Neoproterozoic protoliths of bimodal UHP metaigneous rocks formed during supercontinental rifting along preexisting arc-continent collision orogen, corresponding to dual bimodal magmatism in response to the attempted breakup of the supercontinent Rodinia at about 780 Ma. The first type of bim

Zheng, Yong-Fei; Chen, Ren-Xu; Zhao, Zi-Fu

2009-09-01

225

IODP drilling at Chicxulub  

NASA Astrophysics Data System (ADS)

The terrestrial record is the only source of 3-D ground truth observations on the lithological and structural character of natural impact structures. Of the three largest known impact craters on Earth, Chicxulub is the best preserved because of a slow burial on a tectonically quiet carbonate platform. Our proposal is to drill two wells that address fundamental issues about the structure of the Chicxulub impact crater and its environmental effects. CHICX-01A will focus on constraining the environmental effects of the impact. Current emphasis is on the potential effects of vapor species derived from shocked carbonates and sulfates. Chicx-01A will supply a complete litho-stratigraphic section of the offshore sedimentary portion of the target. Anhydrite is likely to be the most lethal component of the target rocks, but estimates of its constituent percentage range between 10 and 40 %. Half of the crater lies offshore, and seismic indicate that the Mesozoic section is > 1-km thicker offshore than onshore. The thicker the sedimentary layer, the greater the volume of potential pollutants released. If we drill Chicx-01A, we will be able to calibrate the marine reflection data, in terms of depth, strata and lithology, and be better able to convert travel-time to depth for the entire marine reflection dataset. Onshore drilling at Yaxcopoil-1 penetrated 600 m of late Cretaceous calcarenite, dolomite and anhydrite rocks. These data are of significant value in establishing the chemistry of the uppermost section of target rock, and will serve as a baseline for onshore-offshore comparisons if Chicx-01A is drilled. CHICX-02A is specifically designed to sample the peak ring and provide information to constrain formational processes. It is widely believed that peak rings form from hydrodynamic collapse in some form of extension of the structural uplift process that leads to central peaks in smaller complex craters. However, annular rings within terrestrial craters correspond to different morphological elements and this diversity, as well as a lack of common understanding as to what constitutes the planetary equivalent of a peak ring, means that there is currently no consensual agreement on the nature of a topographic peak ring. Drilling through the peak ring at Chicxulub will answer this fundamental cratering question. Geophysical property measurements on the core will be used to improve 3D structural models of the central crater. Of particular interest is the source of the short-wavelength magnetic anomalies that appear to track the peak ring, and may represent enhanced hydrothermal circulation. Our high-resolution 3-D seismic survey, shot in early 2005, will place the drill-hole in its correct structural context. Understanding the mechanism for peak-ring formation is fundamental to understanding cratering. When we can model crater formation in detail, we can better use craters as a diagnostic tool for understanding the surface evolution of the other terrestrial planets. Subtle differences in crater morphology between different planetary bodies provide clues to their near-surface rheology.

Morgan, J.; Urrutia, J.; Gulick, S.; Grieve, R.; Rebolledo, M.; Melosh, J.; Warner, M.; Christeson, G.; Barton, P.

2005-05-01

226

Parallelization of GeoClaw code for modeling geophysical flows with adaptive mesh refinement on many-core systems  

USGS Publications Warehouse

We parallelized the GeoClaw code on one-level grid using OpenMP in March, 2011 to meet the urgent need of simulating tsunami waves at near-shore from Tohoku 2011 and achieved over 75% of the potential speed-up on an eight core Dell Precision T7500 workstation [1]. After submitting that work to SC11 - the International Conference for High Performance Computing, we obtained an unreleased OpenMP version of GeoClaw from David George, who developed the GeoClaw code as part of his PH.D thesis. In this paper, we will show the complementary characteristics of the two approaches used in parallelizing GeoClaw and the speed-up obtained by combining the advantage of each of the two individual approaches with adaptive mesh refinement (AMR), demonstrating the capabilities of running GeoClaw efficiently on many-core systems. We will also show a novel simulation of the Tohoku 2011 Tsunami waves inundating the Sendai airport and Fukushima Nuclear Power Plants, over which the finest grid distance of 20 meters is achieved through a 4-level AMR. This simulation yields quite good predictions about the wave-heights and travel time of the tsunami waves. ?? 2011 IEEE.

Zhang, S.; Yuen, D. A.; Zhu, A.; Song, S.; George, D. L.

2011-01-01

227

Geophysical methods  

SciTech Connect

Geophysical measurements involve no magic or mystery but straightforward applications of physical principles. This book is both a geophysical survey and a reference guide. It explains the physical principles involved in geophysical methods. Over one-third of the text is devoted to seismic methods. Comprehensive topics in the volume include: the measurement of different physical properties and their geological significance; how different kinds of measurements are combined to draw geological conclusions; surface, borehole, airborne, and satellite measurements; computer processing and interactive methods; geodetic, gravity, magnetic, radioactive, heat flow, and electrical methods; interpretation of natural processes such as earthquakes and heat flow; and a summation of present knowledge of the earth.

Robert, E.S.

1989-01-01

228

Footwall Structure of Oceanic Core Complexes: New Insights from Geophysical Data for Footwall Capture of Ascending Melt  

NASA Astrophysics Data System (ADS)

Oceanic core complexes (OCCs) are the footwalls of long-lived detachment faults which form in response to magma-poor crustal accretion processes along the mid-ocean ridge. Although OCC formation is expected to occur at intermediate levels of melt supply to the ridge axis (e.g. Buck et al., 2005), sidescan sonar data have shown that surficial volcanism is absent during part of the OCC life cycle (MacLeod et al., 2009). This implies that footwall capture of ascending melt is an active process during OCC formation. Here, we present the results of a shipboard gravity and deep-towed magnetic survey across actively forming OCCs on the Mid-Atlantic Ridge between 12-14°N. Forward modelling of magnetic data show that the oldest parts of OCCs generally have zero magnetisation, and thus we interpret these areas as comprising non- or low-magnetic upper crustal material such as sheeted dikes and gabbros. In contrast, the younger, domal sections of OCCs often record a very heterogeneous magnetisation pattern, indicative of significant local variations in footwall magnetisation and/or composition over distances of < 6 km (our track spacing). Furthermore, 2.5D and 3D modelling of gravity data reveal a zone of relatively low density material within the ultramafic footwalls of near-axis OCCs. For a density of 2900 kg/m^3, this low density zone (LDZ) must extend for ~3-4 km beneath the seafloor. We interpret this LDZ as comprising a mixture (based on magnetic results) of serpentinised peridotite and gabbroic material that has accreted within the OCC footwall as the detachment fault has captured ascending melt beneath the ridge axis. Older near-axis OCCs in the region are generally associated with a thicker LDZ, which most likely represents more pervasive serpentinisation and melt accumulation with age. References: Buck, W. R., L. L. Lavier & A. N. B. Poliakov, 2005. Modes of faulting at mid-ocean ridges, Nature, 434, 719-723. MacLeod, C. J., R. C. Searle, B. J. Murton, J. F. Casey, C. Mallows, S. C. Unsworth, K. L. Achenbach & M. Harris, 2009. Life cycle of oceanic core complexes, Earth and Planetary Science Letters, 287, 333-344.

Mallows, C.; Searle, R. C.

2010-12-01

229

Geostatistical study of coal and overburden data from the Wasatch Formation in the Powder River Basin, Wyoming. [R-squared statistics used as measure of correlation between drill cutting samples and core samples  

SciTech Connect

A statistical analysis was performed with overburden characterization data that was obtained from a US Forest Service study site in the Powder River Basin, Wyoming. The drilling and overburden characterization program had been performed during 1977 and 1978 and this information was provided to the Laramie Energy Technology Center by the US Forest Service. There were three basic goals that were accomplished during this study. First, find out how overburden data obtained from drill cuttings compares with overburden data obtained from core samples. Second, determine the basic chemical and physical characteristics of the overburden. Third, determine the minimum drill hole spacing required to adequately characterize the overburden. The R-Squared statistic was used as a measure of correlation between drill cutting samples and core samples. Most R-Squared values were less than 50%, therefore, it was concluded that geostatistical structure cannot be predicted accurately during an overburden study when drill cuttings are used. Principal component R-Mode factor analysis with Varimax rotation was used to characterize the overburden. Thirty-one variables were used in the factor analysis. The factor analysis yielded twelve distinct factors which explained ninety percent of the total variation. A two state sequential drilling procedure was developed that moves in a stepwise manner towards the goal of a predetermined level of accuracy until that level is reached. Thus, the desired level of accuracy can be reached without over-drilling an area. 7 figures, 11 tables.

Borgman, L.; Quimby, W.; Sever, C.; Andrew, M.; Youngberg, D.; Davis, F.

1983-05-01

230

Exploration Geophysics  

ERIC Educational Resources Information Center

Describes geophysical techniques such as seismic, gravity, and magnetic surveys of offshare acreage, and land-data gathering from a three-dimensional representation made from closely spaced seismic lines. (MLH)

Espey, H. R.

1977-01-01

231

Exploration Geophysics  

ERIC Educational Resources Information Center

Expansion of activity and confirmation of new technological directions characterized several fields of exploration geophysics in 1977. Advances in seismic-reflection exploration have been especially important. (Author/MA)

Savit, Carl H.

1978-01-01

232

Geophysical signatures of some recently discovered large (> 40 ha) kimberlite pipes on the Alto Cuilo concession in northeastern Angola  

NASA Astrophysics Data System (ADS)

This paper presents a comparison of geophysical responses from several large kimberlite complexes discovered and delineated on the Alto Cuilo concession in the diamond fields of northeastern Angola in the years 2005 to 2008. Several geophysical methods were used in combination with geochemical and mineralogical prioritization techniques to guide exploratory, delineation and bulk sample drilling, in order to rapidly identify and evaluate the kimberlite bodies. The kimberlites were emplaced through Karoo Supergroup sandstones and shales, have eruption ages contemporaneous with the sand-dominated Cretaceous-age Calonda Formation, and are covered by sand-dominated poorly consolidated sediments of the Kalahari Group. Given that sand-dominated non-kimberlite lithologies are magnetically transparent, a low level, high resolution helicopter-borne magnetic gradiometer survey proved to be exceptionally effective in discriminating kimberlite targets, even for low-amplitude anomalies (e.g. 1-2 nT). The helicopter magnetic data outlined approximately 244 probable kimberlite targets and drilling of 103 targets confirmed 80 new kimberlites greater than 5 ha in area. Most kimberlites take the form of well-preserved crater edifices containing a full range of crater-related kimberlite lithologies. Ground gravity and electromagnetic surveys were conducted over all kimberlites prioritized for follow-up investigation. Geophysical responses were ground-truthed against magnetic susceptibility and density measurements, which were routinely collected on all drill cores. The geophysical signatures resolved by the three independent geophysical methods were surprisingly variable and are inferred to be sourced primarily in the crater facies materials, which demonstrate characteristically variable lithologies. Geophysical interpretations guided the drill targeting at all stages of the program at Alto Cuilo, from exploration to evaluation. Combined with geochemical and mineralogical prioritization techniques, the geophysical signatures in magnetic, gravity and electromagnetic data provide a sound basis to guide exploratory, delineation and mini bulk sample drilling of kimberlites buried under 10-70 m of overburden. The significant variability in the geophysical responses from kimberlites that are similar in size, structure and geometry highlights the importance of applying all three independent geophysical methods in order to effectively achieve kimberlite exploration and evaluation goals. The effectiveness of a multidisciplinary approach to kimberlite evaluation is demonstrated in the rapid assessment of a cluster of large kimberlites discovered at Project Alto Cuilo.

Pettit, Wayne

2009-11-01

233

Iron-oxide Magnetic, Morphologic, and Compositional Tracers of Sediment Provenance and Ice Sheet Extent in the ANDRILL AND-1B Drill Core, Ross Sea, Antarctica (Invited)  

NASA Astrophysics Data System (ADS)

The first drilling season of the Antarctic Drilling Program (ANDRILL) recovered a 13.57 million year Miocene through Pleistocene record of paleoclimate change (core AND-1B) within the Ross Sea. The magnetic mineral assemblage records the varying contributions of biological productivity, changing sediment sources, the emergence of volcanic centers, and post-depositional diagenesis. Characterization of bedrock samples from the McMurdo Volcanic Group (MVG) and Transantarctic Mountain (TAM) lithologic units allows us to construct fingerprints for the major source rocks bordering the Ross Sea, and identify their signatures within the AND-1B sediment. Key parameters that can be traced from source rock to sediment for the MVG-derived sediment include a 100-200 C order-disorder transition, titanomaghemite grains with homogenous textures but with substantial Al and Mg content, Fe-spinels with substantial Al, Cr, Mg, and Ti content, and titanomagnetite host grains with 1-3 swarms of ilmenite lamellae (both with variable amounts of oxidation). Distinctive signatures in TAM lithologies include low S-ratios in Koettlitz Group gneisses and Fe-sulfides with magnetite intergrowths in Byrd Glacier basement samples. The Cambrian Granite Harbor Intrusive Complex is characterized by coarse, homogeneous Mn-bearing ilmenite and nearly pure magnetite. The Jurassic dolerites and basalts of the Ferrar Group contain pseudo single domain to stable single domain-sized Fe-oxides with low-Ti content and homogeneous textures. Cu-Fe sulfides are also present in the Ferrar Group. Diamictites in the Pliocene-Pleistocene section of the AND-1B drill core contains Fe-oxide assemblages with MVG-type rock magnetic and textural characteristics, while the Miocene diamictites contain TAM-type signatures. These observations can be explained by increased ice flow from the west during the Miocene and/or the absence of MVG volcanic centers, which had not yet reached a significant size. During the Pliocene and Pleistocene, ice flow was from the south, entraining sediment from MVG volcanic centers south of the drill site. This work demonstrates the utility of using the combination of rock magnetic and electron microscopy signatures of Fe-oxides and Fe-sulfides to serve as provenance tracers in both ice proximal and distal sedimentary units, aiding in the study of ice sheet dynamics, and the identification of ice rafted debris sources and dispersal patterns in the Ross Sea sector of Antarctica.

Brachfeld, S. A.; Pinzon, J.; Darley, J. S.; Sagnotti, L.; Kuhn, G.; Florindo, F.; Wilson, G. S.; Ohneiser, C.; Monien, D.; Joseph, L. H.

2013-12-01

234

Petrology of impactites from El'gygytgyn crater: Breccias in ICDP-drill core 1C, glassy impact melt rocks and spherules  

NASA Astrophysics Data System (ADS)

AbstractEl'gygytgyn is a 18 km diameter, 3.6 Ma old impact crater in NE Siberia. International Continental Scientific <span class="hlt">Drilling</span> Program—El'gygytgyn hole 1C was <span class="hlt">drilled</span> on the frozen crater lake, 2.3 km from the crater center to a final depth of 517 m below the lake floor. Petrographic and geochemical analyses of 26 <span class="hlt">drill</span> <span class="hlt">core</span> samples, three impact melt rocks from the surface, and seven glass spherules from surface deposits outside the crater are used to characterize the impactite inventory at El'gygytgyn. The bottom 98 m of hole 1C intersected monomict brecciated, unshocked, rhyolitic ignimbrite with minor intercalations of polymict breccia and mafic inclusions. These lithologies are overlain by 89 m of polymict breccia whose components occasionally exhibit scarce, low-degree shock metamorphic features. This unit is succeeded by 10 m of suevite that contains about 1 vol% glassy impact melt shards <1 cm in size and a low amount of shock metamorphosed lithic clasts. The suevite is capped by a reworked fallout deposit that constitutes a transition over 4 m into lacustrine sedimentation. A higher abundance of shock metamorphosed lithic clasts, and glass spherules, some with Ni-rich spinel and admixture of an ultramafic component, characterize this unit. We tentatively interpret this impactite section as allochthonous breccia in the vicinity of El'gygytgyn's central ring uplift. The geochemical compositions of seven glass spherules from terrace deposits 2 km outside the crater and eight spherules from the reworked fallout deposit in hole 1C show far greater variability than the composition of impact melt shards and impact melt rocks. Some of these spherules also show strong enrichments in siderophile elements.</p> <div class="credits"> <p class="dwt_author">Wittmann, Axel; Goderis, Steven; Claeys, Philippe; Vanhaecke, Frank; Deutsch, Alexander; Adolph, Leonie</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-07-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">235</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6970158"> <span id="translatedtitle">Petrology and hydrothermal mineralogy of U. S. Geological Survey Newberry 2 <span class="hlt">drill</span> <span class="hlt">core</span> from Newberry caldera, Oregon</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">U.S. Geological Survey Newberry 2 was <span class="hlt">drilled</span> to a depth of 932 m within Newberry caldera. The bottom-hole temperature of 265/sup 0/C is the highest reported temperature of any <span class="hlt">drill</span> hole in the Cascades region of the United States. The upper part of the stratigraphic section pentrated by Newberry 2 consists of caldera fill below which are increasingly more mafic lavas ranging from rhyodacite at 501 m to basalt at 932 m. Measured temperatures shallower than 300 m are less than 35/sup 0/C, and rock alteration consists of hydration of glass and local palagonitization of basaltic tuffs. Incipient zeolitization and partial smectite replacement of ash and pumice occurred throughout the pumiceous lithic tuffs from 300 to 500 m. Higher-temperature alteration of the tuffs to chlorite and mordenite occurs adjacent to a rhyodacite sill at 460--470 m; alteration minerals within the sill consist of pyrrhotite, pyrite, quartz, calcite, and siderite. Below 697 m the rocks are progressively more altered with depth mainly because of increased temperature along a conductive gradient from 100/sup 0/C at 697 m to 265/sup 0/C at 930 m. Fluid inclusions in quartz and calcite indicate that temperature in the past have been higher than at present, most likely due to local confining pressures between impermeable lava flows.</p> <div class="credits"> <p class="dwt_author">Keith, T.E.C.; Bargar, K.E.</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-09-10</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">236</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012AGUFMNS52A..04W"> <span id="translatedtitle">AfricaArray International <span class="hlt">Geophysics</span> Field School: Applications of Near Surface <span class="hlt">Geophysics</span> to challenges encountered in mine planning</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Hard rock exploration and mining presents many opportunities for the effective use of near surface <span class="hlt">geophysics</span>. For over 10 years the AfricaArray international <span class="hlt">geophysics</span> field school has been hosted at a variety of mines in South Africa. While the main objective of the field school is practical training for the next generation of geophysicists, being hosted at a mine has allowed us to investigate applications of near surface <span class="hlt">geophysics</span> in the early stages of mine planning and development as <span class="hlt">geophysics</span> is often cheaper and faster than <span class="hlt">drilling</span>. Several applications include: detailed delineation of dykes and stringer dykes, physical property measurements on <span class="hlt">drill</span> <span class="hlt">core</span> for modeling and marker horizons, determination of overburden thickness, locations of water and faults. Dolerite dykes are usually magnetic and are associated with loss of ground (i.e. where the dyke replaces the ore and thus reduces the amount of ore available) and safety/stability concerns. Thus the accurate mapping of dykes and narrow stringers that are associated with them are crucial to the safe planning of a mine. We have acquired several case studies where ground magnetic surveys have greatly improved on the resolution and detail of airborne magnetic surveys in regions of complicated dyke swarms. In many cases, thin stringer dykes of less than 5 cm have been detected. Physical property measurements of these dykes can be used to distinguish between different ages of dykes. It is important to accurately determine overburden thickness when planning an open pit mine as this directly affects the cost of development. Depending on the nature of the overburden, both refraction seismic and or DC resistivity can provide continuous profiling in the area of interest that fills in gaps between boreholes. DC resistivity is also effective for determining water associated with dykes and structures that may affect mine planning. The field school mainly addresses the training of a variety of students. The <span class="hlt">core</span> students are the <span class="hlt">geophysics</span> Honours students (~4th year undergraduates). In addition, up to 8 students from all over Africa are included in the program to help address practical training in Africa. The final cohort are minority students from the USA. Participants spend a week planning and costing out surveys, a week in the field collecting data using different methods including: gravity, DGPS, magnetics, resistivity, refraction seismic, EM methods, <span class="hlt">core</span> logging and physical property measurements. The final week is spent interpreting and integrating their results. Graduate students are given the opportunity to instruct on the field school and manage the logistics for a particular method. The field school is unique in Africa and satisfies a need for practical training with limited resources, with a rare blend of cultural interactions!</p> <div class="credits"> <p class="dwt_author">Webb, S. J.; Jones, M. Q.; Durrheim, R. J.; Nyblade, A.; Snyman, Q.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">237</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://files.eric.ed.gov/fulltext/ED327713.pdf"> <span id="translatedtitle"><span class="hlt">Drill</span> Presses.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p class="result-summary">These instructional materials provide an orientation to the <span class="hlt">drill</span> press for use at the postsecondary level. The first of seven sections lists seven types of <span class="hlt">drill</span> presses. The second section identifies 14 <span class="hlt">drill</span> press parts. The third section lists 21 rules for safe use of <span class="hlt">drilling</span> machines. The fourth section identifies the six procedures for…</p> <div class="credits"> <p class="dwt_author">Engelbrecht, Nancy; And Others</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">238</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFMPP41A1611A"> <span id="translatedtitle">Temperature and Aridity in Tropical East Africa Over the Past 200,000 Years: Reconstructions from the Lake Malawi <span class="hlt">Drill</span> <span class="hlt">Core</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Tropical heating is the driving force behind global atmospheric circulation and thus is an essential component to our understanding of climate dynamics through time. We present a record of temperature and aridity from Lake Malawi, the largest and southern-most of the large East African Rift lakes, which extends from 9 to 14 °S. The temperature record is based on TEX86 (TetraEther indeX of tetraethers with 86 carbon atoms) analyses on a <span class="hlt">drill</span> <span class="hlt">core</span> from the central basin of the lake, which provides a new record from 39 to 140 m burial depth, extending to approximately 200kyr BP. (This record will extend to the <span class="hlt">core</span> bottom at 378 m below lake floor when completed.) Average lake surface temperature during the past 200kyr was ~25.5°C, with temperature values ranging from 22 to 29°C. When compared to earlier studies, the range of temperatures over the most recent glacial-interglacial transition (MIS 2 to 1) exceeds that of any time earlier in this ~ 200kyr record. No consistent relationship exists between temperature and aridity as indicated by Ca (calcite) abundance in the sediments. Cyclic behavior on orbital time scales is apparent in both temperature and Ca records, however not at the same frequencies. Superimposed on the orbital scale variability are higher frequency, millennial shifts of 2 - 3°C, which undoubtedly impacted ecosystem dynamics and hominin migration on the East African landscape, at least in the vicinity of Lake Malawi, over the past 200,000 years. The regional extent of this climate history cannot be ascertained until comparable records are recovered through <span class="hlt">drilling</span> the other great lakes of the East African Rift Valley.</p> <div class="credits"> <p class="dwt_author">Abbott, A. N.; Johnson, T. C.; Berke, M. A.; Werne, J. P.; Schouten, S.; Sinninghe Damste, J. S.; Brown, E. T.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">239</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.er.usgs.gov/publication/70013111"> <span id="translatedtitle">Element mobility studies of two <span class="hlt">drill-cores</span> from the Go??temar Granite (Kra??kema??la test site), southeast Sweden</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">A pilot study was carried out on two relatively deep <span class="hlt">drill-cores</span> (??? 600 m) from the Go??temar Granite massif in S.E. Sweden. This granite is typical of the 1400-Ma anorogenic granites of the northern hemisphere. Samples from representative, unfractured parts of the <span class="hlt">cores</span>, together with four samples taken along a profile tangential to a fracture plane at ??? 280-m depth, were investigated chemically, mineralogically and isotopically. The results show that after crystallisation, subtle and pervasive open-system modifications of the trace-element chemistry of the granite took place. Whereas the major-element chemistry and minera-logical data emphasised the relative homogeneity of the Go??temar Granite samples investigated, trace elements such as U, Rb, and Pb revealed irregular distributions which are probably the result of large-scale hydrothermal alteration processes. This conclusion is supported by isotopic studies which indicate that whole-rock samples were open to a gain or loss of Pb and possibly U at ??? 420 ?? 171 Ma ago. In addition, isotopic data for U-Pb and U-Ra are consistent with a recent minor loss of U. The pervasive alteration and the more recent mobilisation of U are evident to a depth of at least 600 m. The effects are most prevalent along major fracture zones and within the upper 250-300 m of one <span class="hlt">drill</span>-hole where a high frequency of crush zones has been noted. Higher Fe oxidation ratios, higher Rb contents, lower U contents and correspondingly higher Th/U ratios, all characterise this zone. ?? 1985.</p> <div class="credits"> <p class="dwt_author">Smellie, J. A. T.; Stuckless, J. S.</p> <p class="dwt_publisher"></p> <p class="publishDate">1985-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">240</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5568347"> <span id="translatedtitle">1991 <span class="hlt">drill</span> bit classifier</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Whether <span class="hlt">drilling</span> soft, swelling gumbo formations along the Gulf Coast, harder Green River shales in Wyoming or really tough and abrasive quartzite, basalt or Devonian chert deposits in the Permian basin, choosing the best bit for the job is important if optimum <span class="hlt">drilling</span> and cost efficiency are to be maintained. To make the selection process easier, WORLD OIL has compiled a comprehensive, yet simple-to-use guide for classifying bits. This paper is divided into six major formation categories roughly corresponding to those used by the International Association of <span class="hlt">Drilling</span> Contractors (IADC). Within these are listed virtually all commonly available <span class="hlt">drilling</span> and <span class="hlt">coring</span> bits by type and manufacturer. To use the guide, simply identify the formation to be <span class="hlt">drilled</span>, decide whether a rock, diamond, PDC or hybrid bit is most appropriate, choose the manufacturer and scan the bits available. In fact, bits from all manufacturers can readily be compared.</p> <div class="credits"> <p class="dwt_author">Not Available</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-09-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_11");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return 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title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">241</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.usgs.gov/ds/660/"> <span id="translatedtitle">Construction diagrams, <span class="hlt">geophysical</span> logs, and lithologic descriptions for boreholes USGS 103, 105, 108, 131, 135, NRF-15, and NRF-16, Idaho National Laboratory, Idaho</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">This report, prepared in cooperation with the U.S. Department of Energy, summarizes construction, <span class="hlt">geophysical</span>, and lithologic data collected from about 4,509 feet of <span class="hlt">core</span> from seven boreholes deepened or <span class="hlt">drilled</span> by the U.S. Geological Survey (USGS), Idaho National Laboratory (INL) Project Office, from 2006 to 2009 at the INL. USGS 103, 105, 108, and 131 were deepened and <span class="hlt">cored</span> from 759 to 1,307 feet, 800 to 1,409 feet, 760 to 1,218 feet, and 808 to 1,239 feet, respectively. Boreholes USGS 135, NRF-15, and NRF-16 were <span class="hlt">drilled</span> and continuously <span class="hlt">cored</span> from land surface to 1,198, 759, and 425 feet, respectively. <span class="hlt">Cores</span> were photographed and digitally logged by using commercially available software. Borehole descriptions summarize location, completion date, and amount and type of <span class="hlt">core</span> recovered.</p> <div class="credits"> <p class="dwt_author">Hodges, Mary K.V.; Orr, Stephanie M.; Potter, Katherine E.; LeMaitre, Tynan</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">242</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/59914"> <span id="translatedtitle">Reaction of Topopah Spring tuff with J-13 water at 150{sup 0}C: samples from <span class="hlt">drill</span> <span class="hlt">cores</span> USW G-1, USW GU-3, USW G-4, and UE-25h No. 1</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Samples of Topopah Spring tuff selected from vertical <span class="hlt">drill</span> holes USW G-1, GU-3, and G-4, and from the horizontal air-<span class="hlt">drilled</span> hole at Fran Ridge were reacted with J-13 water at 150{sup 0}C. The primary purpose of these experiments was to compare the resulting solution chemistries to estimate the degree of homogeneity that might be expected in thermally affected ground water in a potential nuclear waste repository at Yucca Mountain. The second purpose was to relate data obtained from welded devitrified Topopah Spring tuff collected from the potential repository depth to that previously obtained using outcrop samples. The results show very similar aqueous phase chemistries for all samples after reaction for times up to 70 days. The largest difference in final solution concentrations was for silica in one of the samples from Fran Ridge. All vertical <span class="hlt">drill</span> <span class="hlt">core</span> samples gave results for silica that were in agreement to within +-6 ppM and indicated solubility controlled by cristobalite. The results for reaction at 150{sup 0}C are in agreement with those obtained in previous experiments using surface outcrop samples from Fran Ridge. The major difference between the <span class="hlt">drill</span> <span class="hlt">core</span> results and the outcrop samples is found in the data for room-temperature rinse solutions. The outcrop samples show relatively large amounts of soluble salts that can be easily removed at room temperature. The data for room-temperature rinsing of <span class="hlt">drill</span> <span class="hlt">core</span> samples show no significant quantities of readily soluble salts. This result is particularly significant for the samples from the air-<span class="hlt">drilled</span> hole at Fran Ridge, since <span class="hlt">drilling</span> fluid that might have removed soluble salts was not used in the portion of the hole from which the samples were obtained. This result strongly suggests that the presence of soluble salts is a surface evaporation phenomenon, and that such materials are unlikely to be present at the depth of the repository.</p> <div class="credits"> <p class="dwt_author">Oversby, V.M.</p> <p class="dwt_publisher"></p> <p class="publishDate">1985-03-03</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">243</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013GPC...110..420B"> <span id="translatedtitle">Iron oxide tracers of ice sheet extent and sediment provenance in the ANDRILL AND-1B <span class="hlt">drill</span> <span class="hlt">core</span>, Ross Sea, Antarctica</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The AND-1B <span class="hlt">drill</span> <span class="hlt">core</span> recovered a 13.57 million year Miocene through Pleistocene record from beneath the McMurdo Ice Shelf in Antarctica (77.9°S, 167.1°E). Varying sedimentary facies in the 1285 m <span class="hlt">core</span> indicate glacial-interglacial cyclicity with the proximity of ice at the site ranging from grounding of ice in 917 m of water to ice free marine conditions. Broader interpretation of climatic conditions of the wider Ross Sea Embayment is deduced from provenance studies. Here we present an analysis of the iron oxide assemblages in the AND-1B <span class="hlt">core</span> and interpret their variability with respect to wider paleoclimatic conditions. The <span class="hlt">core</span> is naturally divided into an upper and lower succession by an expanded 170 m thick volcanic interval between 590 and 760 m. Above 590 m the Plio-Pleistocene glacial cycles are diatom rich and below 760 m late Miocene glacial cycles are terrigenous. Electron microscopy and rock magnetic parameters confirm the subdivision with biogenic silica diluting the terrigenous input (fine pseudo-single domain and stable single domain titanomagnetite from the McMurdo Volcanic Group with a variety of textures and compositions) above 590 m. Below 760 m, the Miocene section consists of coarse-grained ilmenite and multidomain magnetite derived from Transantarctic Mountain lithologies. This may reflect ice flow patterns and the absence of McMurdo Volcanic Group volcanic centers or indicate that volcanic centers had not yet grown to a significant size. The combined rock magnetic and electron microscopy signatures of magnetic minerals serve as provenance tracers in both ice proximal and distal sedimentary units, aiding in the study of ice sheet extent and dynamics, and the identification of ice rafted debris sources and dispersal patterns in the Ross Sea sector of Antarctica.</p> <div class="credits"> <p class="dwt_author">Brachfeld, Stefanie; Pinzon, Juliana; Darley, Jason; Sagnotti, Leonardo; Kuhn, Gerhard; Florindo, Fabio; Wilson, Gary; Ohneiser, Christian; Monien, Donata; Joseph, Leah</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-11-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">244</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6565005"> <span id="translatedtitle">Cascade geothermal <span class="hlt">drilling</span>/corehole N-3</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Two <span class="hlt">core</span> holes have been completed on the flanks of Newberry Volcano, Oregon. <span class="hlt">Core</span> holes GEO N-1 has a heat flow of 180 mWm-2 reflecting subsurface temperature sufficient for commercial exploitation of geothermally generated electricity. GEO N-3, which has a heat flow of 86 mWm-2, is less encouraging. Considerable emphasis has been placed on the rain curtain'' effect with the hope that a detailed discussion of this phenomenon at two distinct localities will lead to a better understanding of the physical processes in operation. <span class="hlt">Core</span> hole GEO N-1 was <span class="hlt">cored</span> to a depth of 1387 m at a site located 9.3 km south of the center of the volcano. <span class="hlt">Core</span> hole GEO N-3 was <span class="hlt">cored</span> to a depth of 1220 m at a site located 12.6 km north of the center of the volcano. Both <span class="hlt">core</span> holes penetrated interbedded pyroclastic lava flows and lithic tuffs ranging in composition from basalt to rhyolite with basaltic andesite being the most common rock type. Potassium-argon age dates range up to 2 Ma. Difficult <span class="hlt">drilling</span> conditions were encountered in both <span class="hlt">core</span> holes at depths near the regional water table. Additionally, both <span class="hlt">core</span> holes penetrate three distinct thermal regimes (isothermal (the rain curtain), transition, and conductive) each having its own unique features based on <span class="hlt">geophysical</span> logs, fluid geochemistry, age dates, and rock alteration. Smectite alteration, which seems to control the results of surface geoelectrical studies, begins in the isothermal regime close to and perhaps associated with the regional water table.</p> <div class="credits"> <p class="dwt_author">Swanberg, C.A.</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-07-19</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">245</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6659034"> <span id="translatedtitle">Cascade geothermal <span class="hlt">drilling</span>/corehole N-1</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Two <span class="hlt">core</span> holes have been completed on the flanks of Newberry Volcano, Oregon. <span class="hlt">Core</span> hole GEO N-1 has a heat flow of 180 mWm-2 reflecting subsurface temperature sufficient for commerical exploitation of geothermally generated electricity. GEO N-3, which has a heat flow of 86 mWm-2, is less encouraging. Considerable emphasis has been placed on the ''rain curtain'' effect with the hope that a detailed discussion of this phenomenon at two distinct localities will lead to a better understanding of the physical processes in operation. <span class="hlt">Core</span> hole GEO N-1 was <span class="hlt">cored</span> to a depth of 1387 m at a site located 9.3 km south of the center of the volcano. <span class="hlt">Core</span> hole GEO N-3 was <span class="hlt">cored</span> to a depth of 1220 m at a site located 12.6 km north of the center of the volcano. Both <span class="hlt">core</span> holes penetrated interbedded pyroclastic lava flows and lithic tuffs ranging in composition from basalt to rhyolite with basaltic andesite being the most common rock type. Potassium-argon age dates range up to 2 Ma. Difficult <span class="hlt">drilling</span> conditions were encountered in both <span class="hlt">core</span> holes at depths near the regional water table. Additionally, both <span class="hlt">core</span> holes penetrate three distinct thermal regimes (isothermal (the rain curtain), transition, and conductive) each having its own unique features based on <span class="hlt">geophysical</span> logs, fluid geochemistry, age dates, and rock alteration. Smectite alteration, which seems to control the results of surface geoelectrical studies, begins in the isothermal regime close to and perhaps associated with the regional water table. 28 refs., 15 figs., 2 tabs.</p> <div class="credits"> <p class="dwt_author">Swanberg, C.A.; Combs, J. (Geothermal Resources International, Inc., San Mateo, CA (USA)); Walkey, W.C. (GEO Operator Corp., Bend, OR (USA))</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-07-19</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">246</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.er.usgs.gov/publication/70047525"> <span id="translatedtitle">Correction to “Constraints on the stress state of the San Andreas Fault with analysis based on <span class="hlt">core</span> and cuttings from San Andreas Fault Observatory at Depth (SAFOD) <span class="hlt">drilling</span> phases 1 and 2”</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">This article corrects: Constraints on the stress state of the San Andreas Fault with analysis based on <span class="hlt">core</span> and cuttings from San Andreas Fault Observatory at Depth (SAFOD) <span class="hlt">drilling</span> phases 1 and 2. Vol. 114, Issue B11, Article first published online: 5 NOV 2009.</p> <div class="credits"> <p class="dwt_author">Tembe, Sheryl; Lockner, David; Wong, Teng-fong</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">247</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFM.T51B2048K"> <span id="translatedtitle">Microstructure and heterogeneity of the Chelungpu fault revealed by Taiwan Chelungpu fault <span class="hlt">Drilling</span> project (TCDP) Hole C <span class="hlt">cores</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Chelungpu thrust fault is an active fault having generated earthquake the 1999 Mw7.6 Chi-Chi earthquake. The Taiwan Chelungpu fault <span class="hlt">Drilling</span> project (TCDP) <span class="hlt">drilled</span> two vertical holes (Hole A and B) and one side-track hole from Hole B (Hole C). The samples from Hole C preserve whole structures including a possible primary slip zone and other older slip zones. Identification of the slip zone of a recent earthquake is important to understand slip mechanism with combining seismological and geological data. In this presentation we show microstructure and chemical composition of the fault zone and discuss its heterogeneity on the fault surface by comparing the Chi-Chi principle slip zone (PSZ) in Hole C with those in Hole A and B. The 12 cm-thick Hole C fault zone is divided into thin 16 layers made of gouges composed of quartz, feldspar and clay minerals. Results of microstructural observation suggest that 2 cm - thick lowest layer in the 12 cm fault zone is related to Chi-Chi earthquake and its PSZ is located within a thin 2mm zone with adjoining drag structure. Comparing our results from Hole C samples with previous studies on the holes A and B, it appears that the PSZ activated by Chi-Chi earthquake is heterogeneious on the fault zone. PSZ in Hole B is also 2 mm-thick and showed a layered structure with very fine grains (Aubourg et al., 2010 presentation in WPGM T33B-03; Chou et al., 2010 poster in WPGM T31A-061). In contranst, PSZ in Hole A is 2 cm-thick and shows ramdom fabric (Boullier et al., 2009). These structures are comparable to those obtained by high velocity rotary shear experiment under not water saturated condition (Ujiie et al., 2010 presentation in JPGU SSS019-15; Boutareaud et al., 2008) where thermal pressurization occurred in the slip zone. From the observations of the PSZ in the three holes, we discuss the slip zone heterogeneity by thermal pressurization model applying to the observed different microstructures to understand the possible dynamic mechanism of faulting for a large slip.</p> <div class="credits"> <p class="dwt_author">Kawabata, K.; Chen, C.; Ma, K.; Boullier, A.; Iizuka, Y.; Tanaka, H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">248</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/936573"> <span id="translatedtitle">Site Selection for DOE/JIP Gas Hydrate <span class="hlt">Drilling</span> in the Northern Gulf of Mexico</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">In the late spring of 2008, the Chevron-led Gulf of Mexico Gas Hydrate Joint Industry Project (JIP) expects to conduct an exploratory <span class="hlt">drilling</span> and logging campaign to better understand gas hydrate-bearing sands in the deepwater Gulf of Mexico. The JIP Site Selection team selected three areas to test alternative geological models and <span class="hlt">geophysical</span> interpretations supporting the existence of potential high gas hydrate saturations in reservoir-quality sands. The three sites are near existing <span class="hlt">drill</span> holes which provide geological and <span class="hlt">geophysical</span> constraints in Alaminos Canyon (AC) lease block 818, Green Canyon (GC) 955, and Walker Ridge (WR) 313. At the AC818 site, gas hydrate is interpreted to occur within the Oligocene Frio volcaniclastic sand at the crest of a fold that is shallow enough to be in the hydrate stability zone. <span class="hlt">Drilling</span> at GC955 will sample a faulted, buried Pleistocene channel-levee system in an area characterized by seafloor fluid expulsion features, structural closure associated with uplifted salt, and abundant seismic evidence for upward migration of fluids and gas into the sand-rich parts of the sedimentary section. <span class="hlt">Drilling</span> at WR313 targets ponded sheet sands and associated channel/levee deposits within a minibasin, making this a non-structural play. The potential for gas hydrate occurrence at WR313 is supported by shingled phase reversals consistent with the transition from gas-charged sand to overlying gas-hydrate saturated sand. <span class="hlt">Drilling</span> locations have been selected at each site to 1) test geological methods and models used to infer the occurrence of gas hydrate in sand reservoirs in different settings in the northern Gulf of Mexico; 2) calibrate <span class="hlt">geophysical</span> models used to detect gas hydrate sands, map reservoir thicknesses, and estimate the degree of gas hydrate saturation; and 3) delineate potential locations for subsequent JIP <span class="hlt">drilling</span> and <span class="hlt">coring</span> operations that will collect samples for comprehensive physical property, geochemical and other analyses.</p> <div class="credits"> <p class="dwt_author">Hutchinson, D.R. (USGS); Shelander, D. (Schlumberger, Houston, TX); Dai, J. (Schlumberger, Hoston, TX); McConnell, D. (AOA Geophysics, Inc., Houston, TX); Shedd, W. (Minerals Management Service); Frye, M. (Minerals Management Service); Ruppel, C. (USGS); Boswell, R.; Jones, E. (Chevron Energy Technology Corp., Houston, TX); Collett, T.S. (USGS); Rose, K.; Dugan, B. (Rice Univ., Houston, TX); Wood, W. (U.S. Naval Research Laboratory); Latham, T. (Chevron Energy Technology Corp., Houston, TX)</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-07-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">249</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/7160101"> <span id="translatedtitle">Well <span class="hlt">drilling</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">This patent describes a method for <span class="hlt">drilling</span> wellbores in at least one producing formation in an oil and/or gas field for maximum development of the field with the least number of wellbores. The improvement described here comprises providing at least two spaced apart longitudinally extending <span class="hlt">drilling</span> zones which are essentially parallel to one another. The two <span class="hlt">drilling</span> zones extend across a substantial portion of the field. A first downwardly extending wellbore from a first site on a first of the <span class="hlt">drilling</span> zones is <span class="hlt">drilled</span>. The first wellbore curves toward the second of the <span class="hlt">drilling</span> zones, straightening the first wellbore when it reaches a predetermined producing formation.</p> <div class="credits"> <p class="dwt_author">Schuh, F.J.</p> <p class="dwt_publisher"></p> <p class="publishDate">1986-11-11</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">250</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012AGUFM.V13B2839P"> <span id="translatedtitle">Project Hotspot: Temporal Compositional Variation in Basalts of the Kimama <span class="hlt">Core</span> and Implications for Magma Source Evolution, Snake River Scientific <span class="hlt">Drilling</span> Project, Idaho</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Project Hotspot produced continuous <span class="hlt">core</span> from three <span class="hlt">drill</span> sites in the Snake River plain, including 1912 m of <span class="hlt">core</span> from the Kimama <span class="hlt">drill</span> site on the axis of the plain. Ongoing major and trace element chemical characterization of the Kimama <span class="hlt">core</span> and new 40Ar/39Ar and paleomagnetic age data demonstrate temporal variations in the evolution of Snake River Plain volcanism. Cyclic fluctuations in magma chemistry identify over a hundred chemically distinct basalt flow groups (comprising 550 individual lava flows) within 54 periods of volcanic activity, separated by hiatuses of decades to many millennia. From a surface age of 700 ka to a bottom-hole age of 6.5 Ma, the Kimama <span class="hlt">core</span> records the presence of several nearly coeval but compositionally different lava flows, ranging from highly evolved lavas to non-evolved tholeiites. Determining whether Kimama lavas are genetically unrelated or extreme differentiates of a single magma batch relies upon a combination of detailed chemostratigraphy and absolute and relative age data. Age and geochemical data introduce new ideas on the role of multiple magma sources and/or differentiation processes in the development of central Snake River Plain volcanic systems. The relatively short gestation of evolved liquids is demonstrated throughout the Kimama <span class="hlt">core</span>, with evidence for cyclic fractionation of mafic lavas at depths of 318 m, 350 m, 547 m, and 1078 m. Here, highly evolved lava flows (FeOT 16.0-18.4 wt %; TiO2 3.43-4.62 wt %) are stratigraphically bounded by more primitive tholeiitic basalts (FeOT 9.9-14.8 wt%; TiO2 1.22-3.56 wt%) within the same inclination range, suggesting that cyclic fractionation is a regular feature of shield volcano development on the central Snake River Plain. Between 1.60 ± 0.13 Ma (453.5 m depth) and 1.54 ± 0.15 Ma (320.0 m depth), Kimama lavas ranged in composition from primitive tholeiite (FeOT 11.7 wt %; TiO2 1.76 wt %) to evolved basalt (FeOT 16.0 wt %; TiO2 4.00 wt %). At depths of 1119 m and 1138 m, evolved lava flows (FeOT 17.2 and 17.0 wt %; TiO2 4.20 and 4.09 wt %, respectively) of negative polarity are stratigraphically bounded by more primitive tholeittic lava flows (FeOT 13.6 and 14.5 wt %; TiO2 2.92 and 3.24 wt %, respectively) of positive polarity, a chronological transition that may represent many millennia and magma source variability. Kimama <span class="hlt">core</span> stratigraphy as well as paleomagnetic, and radiometric age data demonstrate that mafic volcanism on the central Snake River Plain has been relatively continuous for the last 6.5 Ma. The compositional variability in Kimama basalts introduces broader implications for the timing of cyclic fractionation processes and the development of regional magma sources.</p> <div class="credits"> <p class="dwt_author">Potter, K. E.; Shervais, J. W.; Champion, D.; Duncan, R. A.; Christiansen, E. H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">251</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2001M%26PS...36..651K"> <span id="translatedtitle">Petrography, geochemistry, and 40Ar-39Ar ages of impact melt rocks and breccias from the Ames Impact Structure, Oklahoma: The Nicor Chestnut 18-4 <span class="hlt">drill</span> <span class="hlt">core</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The 15-km-diameter Ames structure in northwestern Oklahoma is located 2.75 km below surface in Cambro-Ordovician Arbuckle dolomite, which is overlain by Middle Ordovician Oil Creek Formation shale. The feature is marked by two concentric ring structures, with the inner ring of about 5 km diameter probably representing the collapsed remnant of a structural uplift composed of brecciated Precambrian granite and Arbuckle dolomite. Wells from both the crater rim and the central uplift are oil- and gas-producing, making Ames one of the economically important impact structures. Petrographic, geochemical, and age data were obtained on samples from the Nicor Chestnut 18-4 <span class="hlt">drill</span> <span class="hlt">core</span>, off the NW flank of the central uplift. These samples represent the largest and best examples of impact melt breccia obtained so far from the Ames structure. They contain carbonate rocks which, therefore, are derived from the target sequence. The chemical composition of the impact melt breccias is similar to that of target granite, with variable carbonate admixture. Some impact melt rocks are enriched in siderophile elements indicating the possible presence of a meteoritic component. Based on stratigraphic arguments, the age of the crater was estimated at 470 Ma. Previous 40Ar-39Ar dating attempts of impact melt breccias from the Dorothy 1-19 <span class="hlt">core</span> yielded plateau ages of about 285 Ma, which is in conflict with the stratigraphic age. The new 40Ar-39Ar age data obtained on the melt breccias from the Nicor Chestnut <span class="hlt">core</span> by UV laser spot analysis, resulted in a range of ages with maxima around 300 Ma. These data could reflect processes related either the regional Nemaha Uplift or resetting due to hot brines active on a midcontinent-wide scale, perhaps in related to the Alleghenian and Ouachita orogenies. The age data indicate an extended burial phase associated with thermal overprint during Late Pennsylvanian-Permian.</p> <div class="credits"> <p class="dwt_author">Koeberl, Christian; Reimold, Wolf Uwe; Kelley, Simon P.</p> <p class="dwt_publisher"></p> <p class="publishDate">2001-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">252</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011HydJ...19..237A"> <span id="translatedtitle">Helium measurements of pore fluids obtained from the San Andreas Fault Observatory at Depth (SAFOD, USA) <span class="hlt">drill</span> <span class="hlt">cores</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">4He accumulated in fluids is a well established geochemical tracer used to study crustal fluid dynamics. Direct fluid samples are not always collectable; therefore, a method to extract rare gases from matrix fluids of whole rocks by diffusion has been adapted. Helium was measured on matrix fluids extracted from sandstones and mudstones recovered during the San Andreas Fault Observatory at Depth (SAFOD) <span class="hlt">drilling</span> in California, USA. Samples were typically collected as subcores or from drillcore fragments. Helium concentration and isotope ratios were measured 4-6 times on each sample, and indicate a bulk 4He diffusion coefficient of 3.5 ± 1.3 × 10-8 cm2 s-1 at 21°C, compared to previously published diffusion coefficients of 1.2 × 10-18 cm2 s-1 (21°C) to 3.0 × 10-15 cm2 s-1 (150°C) in the sands and clays. Correcting the diffusion coefficient of 4Hewater for matrix porosity (˜3%) and tortuosity (˜6-13) produces effective diffusion coefficients of 1 × 10-8 cm2 s-1 (21°C) and 1 × 10-7 (120°C), effectively isolating pore fluid 4He from the 4He contained in the rock matrix. Model calculations indicate that <6% of helium initially dissolved in pore fluids was lost during the sampling process. Complete and quantitative extraction of the pore fluids provide minimum in situ porosity values for sandstones 2.8 ± 0.4% (SD, n = 4) and mudstones 3.1 ± 0.8% (SD, n = 4).</p> <div class="credits"> <p class="dwt_author">Ali, S.; Stute, M.; Torgersen, T.; Winckler, G.; Kennedy, B. M.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-02-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">253</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006AGUFMSA41B1417W"> <span id="translatedtitle"><span class="hlt">Geophysical</span> Institute Magnetometer Array</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The <span class="hlt">Geophysical</span> Institute Magnetometer Array (GIMA) consists of twelve magnetometer stations distributed across Alaska cutting the auroral oval. Each station is equipped with a ring-<span class="hlt">core</span>, fluxgate magnetometer, GPS clock and data logger. Data are returned from each station to the <span class="hlt">Geophysical</span> Institute, University of Alaska where it is verified, archived, and made available to the space science community. The GIMA web page, at http://magnet.gi.alaska.edu/, provides the data from eight stations online in real-time. The GIMA web page also provides limited data access from five Russian magnetometer stations. The GIMA data set available online spans the time period 1995 to the present. This presentation describes the current operation of the array, its capabilities (data collection parameters), the web site, and methods for acessing the data set. Current efforts to improve data access and integrate the data set with online virtual observatories is described.</p> <div class="credits"> <p class="dwt_author">Wilkinson, D.; Heavner, M. J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">254</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004AGUFM.B53B0996W"> <span id="translatedtitle">Microbial Ecosystem In The Oldest Freshwater Lake Revealed From A <span class="hlt">Drill</span> <span class="hlt">Core</span> Of The 2.76 Ga Hardey Formation, Pilbara District, Western Australia</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Hardey Formation in the Pilbara district of Western Australia, is the oldest known (2.76 Ga) lacustrine deposit, was one of eight targets of the Archean Biosphere <span class="hlt">Drilling</span> Project (ABDP). Rocks in the <span class="hlt">drilling</span> area have been subjected to very low-grade metamorphism (zeolites facies). The recovered <span class="hlt">drill</span> <span class="hlt">core</span> (~145 m in depth) is divisible into two depth zones: (1) the upper zone (<~80 m), comprising mostly coare-grained, gray, arkosic sandstones, and (2) the lower zone, comprising alternating layers of finely laminated, black shales and calcareous sandstones. We selected 26 samples from the lower zone at 2.5-m intervals, and conducted petrographical, mineralogical, and geochemical investigations (e.g., chemical mapping of major and trace element (including REEs); organic and carbonate C, and S contents; C isotope). Bedding planes are well preserved, comprising alternating layers of organic-C rich clay and organic-C poor carbonate (10-20 µm). Presence of cross-lamination suggests a low energy depositional environment, probably a shallow lake. Major and trace element contents of all samples are quite homogeneous. Organic C- and pyrite S contents fall in narrow ranges, from 0.2 to 0.7wt% (a mean value = 0.5wt% and s.d. = 0.1wt%) and from 0.01 to 0.1wt% (a mean value = 0.04 wt%; s.d. = 0.02 wt%), respectively. Compared to average Archean marine shales (organic C = 0.45 wt%; S = 0.1 wt%), the Hardy shales are comparable in organic C but are much depleted in pyrite S contents. The low S/C ratios of the Hardy shales concur with a freshwater depositional interpretation. The C isotope values for the organic C vary from -36.6 to -27.6% (a mean value = -32.7%; s.d. = 1.8%). There is no stratigraphic trend, but theycorrelate well with the lithology: -31.9 to -27.6% (a mean value = -30.4%) for disseminated-grains and seams of organic C in calcareous sandstone; and -36.6 to 32.6% (a mean value = -33.4%) for finely-laminated black shales. The heavier values may represent microbial communities in shallow water, while the lighter values represent microbial communities in deeper water. The carbon isotope systematics in the Hardy Formation are essentially identical to those of the 2.75 Ga marine shales at Kidd Creek, Ontario, Canada. These data suggest that the fresh-water ecosystems were already as diversed as marine ecosystems at 2.76 Ga ago.</p> <div class="credits"> <p class="dwt_author">Watanabe, Y.; Bevacqua, D. C.; Ohmoto, H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">255</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.er.usgs.gov/publication/70019035"> <span id="translatedtitle">San Andreas fault zone <span class="hlt">drilling</span> project: scientific objectives and technological challenges</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">We are leading a new international initiative to conduct scientific <span class="hlt">drilling</span> within the San Andreas fault zone at depths of up to 10 km. This project is motivated by the need to understand the physical and chemical processes operating within the fault zone and to answer fundamental questions about earthquake generation along major plate-boundary faults. Through a comprehensive program of <span class="hlt">coring</span>, fluid sampling, downhole measurements, laboratory experimentation, and long-term monitoring, we hope to obtain critical information on the structure, composition, mechanical behavior and physical state of the San Andreas fault system at depths comparable to the nucleation zones of great earthquakes. The <span class="hlt">drilling</span>, sampling and observational requirements needed to ensure the success of this project are stringent. These include: 1) <span class="hlt">drilling</span> stable vertical holes to depths of about 9 km in fractured rock at temperatures of up to 300°C; 2) continuous <span class="hlt">coring</span> and completion of inclined holes branched off these vertical boreholes to intersect the fault at depths of 3, 6, and 9 km; 3) conducting sophisticated borehole <span class="hlt">geophysical</span> measurements and fluid/rock sampling at high temperatures and pressures; and 4) instrumenting some or all of these inclined <span class="hlt">core</span> holes for continuous monitoring of earthquake activity, fluid pressure, deformation and other parameters for periods of up to several decades. For all of these tasks, because of the overpressured clay-rich formations anticipated within the fault zone at depth, we expect to encounter difficult <span class="hlt">drilling</span>, <span class="hlt">coring</span> and hole-completion conditions in the region of greatest scientific interest.</p> <div class="credits"> <p class="dwt_author">Hickman, S. H.; Younker, L. W.; Zoback, M. D.</p> <p class="dwt_publisher"></p> <p class="publishDate">1995-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">256</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013AGUFM.V53E..05C"> <span id="translatedtitle">Rhyolites in the Kimberly <span class="hlt">Drill</span> <span class="hlt">Core</span>, Project Hotspot: First Intracaldera Ignimbrite from the Central Snake River Plain, Idaho?</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The rhyolites on the track of the Yellowstone hotspot are the classic examples of continental hotspot volcanism and the study of surface outcrops is maturing rapidly. However, in the central part of the track, where silicic volcanism is most voluminous, compositionally distinctive, and isotopically most anomalous, study of these large magma systems has been hindered because eruptive sources are buried. The 2 km Kimberly <span class="hlt">core</span> helps fill that gap; it penetrates through surficial basalt, deep into the rhyolitic underpinnings on the southern margin of the province. The Kimberly <span class="hlt">core</span> is dominated by thick sections of rhyolite lava and welded ignimbrite, with basalt-sediment intercalations between 241 m and 424 m depth. We tentatively interpret the <span class="hlt">core</span> to include a thick intracaldera tuff. Our preliminary studies suggest that there are three major rhyolite units in the <span class="hlt">core</span>. Rhyolite 3, the uppermost unit, is a nearly 130 m thick, low-silica rhyolite lava. Rhyolite 2 is the most highly evolved with ~75% silica and distinctively resorbed quartz. Rhyolite 1 is at least 1,340 m thick (the base was not cut by the <span class="hlt">core</span>), has no apparent flow contacts or cooling breaks, and may represent a single, thick intracaldera ignimbrite. Paleomagnetic inclinations form a curious V-shaped profile, shallowing by about 18? between 700 and 1700 m depth. We interpret this to be the result of slower cooling of the mid-part of the thick intracaldera ignimbrite. The lower unit is a low-silica rhyolite with high concentrations of Fe2O3 and TiO2--among the highest of any known ignimbrite on the SRP. It is chemically distinct from the upper units, very homogeneous, not vertically zoned, and lacks multiple populations of phenocrysts. It somewhat resembles the regionally extensive ~10 Ma outflow tuff of Wooden Shoe Butte. However, this is one of several large, petrologically similar ignimbrites as young as 8.6 Ma exposed in the Cassia Mountains south of the hole, so further work is needed. Like most rhyolites from the Snake River Plain, all 3 units have the characteristics of A-type rhyolites with high concentrations of alkalies, high Fe/Mg and TiO2/MgO ratios, as well as high concentrations Nb, Y, Zr and Ga. Initial analyses of plag, cpx, and qtz show that all three units are low ?18O rhyolites, like most from the Central Snake River Plain-- ?18O in feldspar ranges from 1‰ in Rhyolite 1 to 3‰ in Rhyolites 2 and 3. In the thick lower ignimbrite, whole-rock ?18O increases systematically from the base upward (0.5‰ to as much as 9‰ in the altered top and ?D ranges from -140 to -180‰). Whole rock variations correlate with water content, apparently controlled by secondary clay. We suggest that these characteristics were largely imposed by their derivation from partial melting of basaltic sills and surrounding older crust. The low ?18O values reflect recycling of hydrothermally altered crustal rocks and indicate progressive incorporation of more hydrothermally altered material into the younger magmas. More work is needed to establish correlation with regional units, understand the emplacement of the rhyolites and their volcanic setting, and ascertain the origin of these distinctive low ?18O, A-type rhyolites.</p> <div class="credits"> <p class="dwt_author">Christiansen, E. H.; McCurry, M. O.; Champion, D. E.; Bolte, T.; Holtz, F.; Knott, T.; Branney, M. J.; Shervais, J. W.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">257</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2003EAEJA.....7237S"> <span id="translatedtitle">Properties, classification, and genetic interpretation of the allochthonous impact formations of the ICDP Chicxulub <span class="hlt">drill</span> <span class="hlt">core</span> YAX-1</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The ICDP <span class="hlt">drilling</span> Yaxcopoil-1 exposes 1510 m of impact-related lithologies. We report here and in related abstracts [1-3] on allochthonous impactites representing a complex layered sequence of polymict breccias, extremely rich in impact melt particles and rather poor in fine-grained matrix. This sequence can be subdivided into 6 units. Their whole rock chemistry reflects a mixture of crystalline rocks and Cretaceous carbonate rocks. The completely crystallized silicate "glass" occurs in discrete particles whereas carbonate melt forms exsolved inclusions in silicate melts and larger bodies of polycrystalline Mg-bearing calcite in unit 6. The stratigraphy, classification, and properties of the impactites are as follows: Unit 1 (Upper sorted suevite): 794.63 m, melt-rich, fine grained, clastic matrix; Unit 2 (Lower sorted suevite): 807.75 m, melt-rich, coarse grained, clastic matrix partly recrystallized, Unit 3 (Upper suevite): 823.25 m, melt rich, very coarse grained, recrystallized matrix; Unit 4 (Middle suevite): 846.09 m, melt rich, very coarse grained, recrystallized matrix; Unit 5 (Suevitic breccia with cataclastic melt rock): 861.06 m, suevitic melt agglomerate with monomictly brecciated melt bodies, coarse grained, crystallized matrix (remelted); Unit 6 (Lower suevite): 884.96 m, suevite with silicate and carbonate melt, very coarse grained; recrystallized matrix; Unit 7 (Cretaceous): 894.94-1510.97 m, displaced bedded carbonates and anhydrite, partially brecciated, with impact breccia dikes. The source material of the layered breccias, derived from the deepest excavation zone, was incorporated into the ejecta plume at a late stage when the bulk of the high rising plume had disappeared from the impact site [3] and distributed globally. The upper section (units 1-4) is interpreted as ballistic "fallout" material from the ejecta plume. The Lower Suevite (unit 6) represents ground surged material deposited as the first layer and then covered with laterally inward moving and brecciated material (unit 5) derived from a coherent melt deposit near to the peak ring. Units 4, 3, 2, and 1 were deposited as fallback material later than units 6 and 5. The grain size sorting of units 2 and 1 may be due to the combined effects of the atmosphere reentering the crater region and aquatic sedimentation. References: [1] Schmitt R. T. et al. [2003], this volume. [2] Hecht L. et al. (2003), this volume. [3] Tagle R. et al. (2003), this volume.</p> <div class="credits"> <p class="dwt_author">Stöffler, D.; Hecht, L.; Kenkmann, T.; Schmitt, R. T.; Wittmann, A.</p> <p class="dwt_publisher"></p> <p class="publishDate">2003-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">258</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6286387"> <span id="translatedtitle">Results of Phase 1 postburn <span class="hlt">drilling</span> and <span class="hlt">coring</span>, Rocky Mountain 1 Underground Coal Gasification Site, Hanna Basin, Wyoming</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The Rocky Mountain 1 (RM1) Underground Coal Gasification (UCG) test consisted of two different module configurations: the controlled retracting injection point (CRIP) and elongated linked well (ELW) configurations. The postburn <span class="hlt">coring</span> of the RM1 UCG site was designed in two phases to fulfill seven objectives outlined in the Western Research Institute's (WRI) annual project plan for 1988--1989. The seven objectives were to (1) delineate the areal extent of the cavities, (2) identify the extent of roof collapse, (3) obtain samples of all major cavity rock types, (4) characterize outflow channels and cavity stratigraphy, (5) characterize the area near CRIP points and ignition points, (6) further define the structural geology of the site, and (7) identify the vertical positioning of the horizontal process wells within the coal seam. Phase 1 of the <span class="hlt">coring</span> was completed in the summer of 1989 and served to partially accomplish all seven objectives. In relation to the seven objectives, WRI determined that (1) the ELW cavity extends farther to the west and the CRIP cavity was located 5--10 feet farther to the south than anticipated; (2) roof collapse was contained within unit A in both modules; (3) samples of all major rock types were recovered; (4) insufficient data were obtained to characterize the outflow channels, but cavity stratigraphy was well defined; (5) bore holes near the CRIP points and ignition point did not exhibit characteristics significantly different from other bore holes in the cavities; (6) a fault zone was detected between VIW=1 and VIW-2 that stepped down to the east; and (7) PW-1 was only 7--12 feet below the top of the coal seam in the eastern part of the ELW module area; and CIW-1 was located 18--20 feet below the top of the coal seam in the CRIP module area. 7 refs., 7 figs., 1 tab.</p> <div class="credits"> <p class="dwt_author">Lindblom, S.R.; Covell, J.R.; Oliver, R.L.</p> <p class="dwt_publisher"></p> <p class="publishDate">1990-09-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">259</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=PB288768"> <span id="translatedtitle">Dry Valley <span class="hlt">Drilling</span> Project (DVDP).</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">This report is the second of a series to be issued as work on the Dry Valley <span class="hlt">Drilling</span> Project proceeds. It contains the results of preliminary studies of <span class="hlt">core</span> samples from the first two boreholes <span class="hlt">drilled</span> into the volcanic rocks of Ross I., summaries of se...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">1973-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">260</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010SPIE.7997E...1L"> <span id="translatedtitle">Study on <span class="hlt">drilling</span> force and delamination in high speed <span class="hlt">drilling</span> carbon fiber reinforce plastics (CFRP)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The carbon fiber reinforced plastics are highly promising materials which widely used in aerospace industry due to their excellent mechanical properties. The delamination is considered a major problem in manufacture the parts and assembly. The thrust force affected the delamination mostly. This paper investigated the <span class="hlt">drilling</span> force, torque, delamination of carbon fibred composite with carbide <span class="hlt">drilling</span> tools and half <span class="hlt">core</span> <span class="hlt">drilling</span> tool. The experiments were carried out under air cooling cutting conditions and the <span class="hlt">drilling</span> force and the damage around the hole using carbide tool and half <span class="hlt">core</span> tool were compared. The experimental results indicated that the <span class="hlt">drilling</span> forces using half <span class="hlt">core</span> <span class="hlt">drill</span> were smaller than that of using carbide tool and the damages around the <span class="hlt">drilling</span> hole using half <span class="hlt">core</span> tool and better than that using carbide <span class="hlt">drill</span>.</p> <div class="credits"> <p class="dwt_author">Liu, Dong; Luo, Xueke; Xu, Honghai</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" 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onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_15");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">261</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60635103"> <span id="translatedtitle">Results from exploratory <span class="hlt">drill</span> hole UE2ce, Northwest Yucca Flat, Nevada Test Site, near the NASH Event</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Exploratory <span class="hlt">drill</span> hole UE2ce was <span class="hlt">drilled</span> in January 1977 to determine geologic and <span class="hlt">geophysical</span> characteristics of this site. This report presents <span class="hlt">geophysical</span> logs, lithology, geologic structure, water table measurements, and physical properties for this <span class="hlt">drill</span> hole. The data are then extrapolated to the NASH site, an event in U2ce, 55.6 m due north of UE2ce.</p> <div class="credits"> <p class="dwt_author">Pawloski</p> <p class="dwt_publisher"></p> <p class="publishDate">1982-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">262</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1982JGR....87.6359F"> <span id="translatedtitle">The Iceland Research <span class="hlt">Drilling</span> Project</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">This issue of the Journal of <span class="hlt">Geophysical</span> Research contains the collected results of the initial studies of a 3-km vertical section of Icelandic crust. The material described in these papers was largely presented at a meeting of the investigators working in this project held in Reykjavík, Iceland, from May 13 to May 15, 1980 Iceland presents a very well exposed example of crust formed at an accretional plate margin, the crest of the Mid-Atlantic Ridge. The desirability of a detailed study of a long vertical section of Icelandic crust by deep <span class="hlt">drilling</span> has been expressed in proposals and recommendations of scientists and international scientific committees since the early 1960's. A formal proposal with descriptions of several alternative <span class="hlt">drill</span> sites was presented in 1975 [Working Group on Deep Crustal <span class="hlt">Drilling</span> in Iceland, 1975], but difficulties in financing a <span class="hlt">drill</span> hole that would penetrate into crustal layer 3 (Vp = 6.5 km/s) delayed implementation of the recommendations.</p> <div class="credits"> <p class="dwt_author">Fridleifsson, Ingvar B.; Gibson, Ian L.; Hall, J. M.; Johnson, H. Paul; Christensen, N. I.; Schmincke, Hans-Ulrich; SchöNharting, Gunther</p> <p class="dwt_publisher"></p> <p class="publishDate">1982-08-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">263</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.usgs.gov/of/1976/0665/report.pdf@displayLabelpdf@notePLATE#texthttp://pubs.usgs.gov/of/1976/0665/plate-1.pdf@displayLabelpdf@notePLATE#texthttp://pubs.usgs.gov/of/1976/0665/plate-2.pdf@displayLabelpdf@notePLATE#texthttp://pubs.usgs.gov/of/1976/0665/plate-3.pdf@displayLabelpdf@notePLATE#texthttp://pubs.usgs.gov/of/1976/0665/plate-4.pdf@displayLabelpdf@notePLATE#texthttp://pubs.usgs.gov/of/1976/0665/plate-5.pdf"> <span id="translatedtitle">Basic data from five <span class="hlt">core</span> holes in the Raft River geothermal area, Cassia County, Idaho</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">meters) were completed in the area (Crosthwaite, 1974), and the Aerojet Nuclear Company, under the auspices of the U.S. Energy Research and Development Administration, was planning some deep <span class="hlt">drilling</span> 4,000 to 6,000 feet (1,200 to 1,800 meters) (fig. 1). The purpose of the <span class="hlt">core</span> <span class="hlt">drilling</span> was to provide information to test <span class="hlt">geophysical</span> interpretations of the subsurface structure and lithology and to provide hydrologic and geologic data on the shallow part of the geothermal system. Samples of the <span class="hlt">core</span> were made available to several divisions and branches of the Geological Survey and to people and agencies outside the Survey. This report presents the basic data from the <span class="hlt">core</span> holes that had been collected to September 1, 1975, and includes lithologic and <span class="hlt">geophysical</span> well logs, chemical analyses of water (table 1), and laboratory analyses of <span class="hlt">cores</span> (table 2) that were completed as of the above date. The data were collected by the Idaho District office, Hydrologic Laboratory, Borehole <span class="hlt">Geophysics</span> Research Project, and <span class="hlt">Drilling</span>, Sampling, and Testing Section, all of the Water Resources Division, and the Branch of Central Environmental Geology of the Geologic Divison.</p> <div class="credits"> <p class="dwt_author">compiled by Crosthwaite, E. G.</p> <p class="dwt_publisher"></p> <p class="publishDate">1976-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">264</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006JGRE..111.6S19Y"> <span id="translatedtitle">Comparison of <span class="hlt">geophysical</span> investigations for detection of massive ground ice (pingo ice)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Six different <span class="hlt">geophysical</span> investigations, (1) ground-penetrating radar, (2) DC resistivity sounding, (3) seismic refraction, (4) very low frequency (VHF) electromagnetic, (5) helicopter borne electromagnetic (HEM), and (6) transient electromagnetic (TEM) techniques, were employed to obtain information on the ice body properties of pingos near Fairbanks, Alaska. The surface nuclear magnetic resonance (NMR) data were also compared from similar sites near one of the study pingos. The <span class="hlt">geophysical</span> investigations were undertaken, along with <span class="hlt">core</span> sampling and permafrost <span class="hlt">drilling</span>, to enable measurement of the ground temperature regime. <span class="hlt">Drilling</span> (ground truthing) results support field <span class="hlt">geophysical</span> investigations, and have led to the development of a technique for distinguishing massive ice and overburden material of the permafrost. The two-dimensional DC resistivity sounding tomography and ground-penetrating radar profiling are useful for ice detection under heterogeneous conditions. However, the DC resistivity sounding investigation required high-quality ground contact and less area coverage. The active layer thickness and the homogeneous horizontal structure of the overburden material are important parameters influencing detection of massive ice in permafrost for most methods such as seismic, TEM, or surface NMR.</p> <div class="credits"> <p class="dwt_author">Yoshikawa, K.; Leuschen, C.; Ikeda, A.; Harada, K.; Gogineni, P.; Hoekstra, P.; Hinzman, L.; Sawada, Y.; Matsuoka, N.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-06-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">265</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013AGUSMGP32A..04F"> <span id="translatedtitle">Magnetostratigraphy and Susceptibility of Deep <span class="hlt">Drilling</span> <span class="hlt">Core</span> SG-1 in the Western Qaidam Basin (ne Tibetan Plateau) and Their Tectonic and Climatic Implications</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Qaidam Basin is the largest intermontane basin of the northeastern Tibetan Plateau and contains a continuous Cenozoic sequence of lacustrine sediments. A nearly 1000 m deep <span class="hlt">drilling</span> (SG-1) with an average <span class="hlt">core</span> recovery of ~95% was carried out in the depocenter of the western Qaidam Basin, aimed to obtain a high-resolution record of the paleoenvironmental evolution and the erosion history. The <span class="hlt">core</span> consists of dark grayish mudstone and grayish siltstone, intercalated with salts and fine sandstones in the upper part. Stepwise alternating field and thermal demagnetization, together with rock magnetic results, revealed a stable remanent magnetization for most samples, carried by magnetite. The polarity sequence consists of sixteen normal and fifteen reverse zones which can be correlated with chrons 1n to 2An of the global geomagnetic polarity time scale. Magnetostratigraphic results date the entire <span class="hlt">core</span> SG-1 at ~2.77 Ma to ~0.1 Ma and yield sediment accumulation rate (SAR) ranging from 26.1 cm/ka to 51.5 cm/ka. Maximum SARs occur within the intervals of ~2.6-2.2 Ma and after ~0.8 Ma indicating two episodic erosional periods. Detailed magnetic susceptibility and rock magnetic properties were analyzed for revealing the significance of ferro(i)magnetic concentration for past changes of climate and erosion. Mass-specific susceptibility (?) shows a striking cyclic and long-term variation. Samples with high ? values are dominated by magnetite and maghemite with pseudo-single-domain properties. In contrast, samples with low ? values contain maghemite from single-domain to multi-domain, and additionally a significant fraction of hematite. Combining with high resolution pollen-spore and geochemical records for representative time intervals, the driving mechanism of ? variation can be explained by low-temperature oxidation in the lake sediments (dry climate). Trends of match with sedimentation rates and are roughly synchronous with the deep-sea ?18O record on a glacial-interglacial timescale. Therefore, magnetic concentration in the western Qaidam Basin sediments is seemingly controlled by both tectonic influence and paleoenvironmental changes, but can be best interpreted by alternations and trends of dry-cold and more humid periods due to Asian drying and global cooling.</p> <div class="credits"> <p class="dwt_author">Fang, X.; Zhang, W.; Appel, E.; Song, C.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">266</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/18598141"> <span id="translatedtitle"><span class="hlt">Drilling</span> systems for extraterrestrial subsurface exploration.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary"><span class="hlt">Drilling</span> consists of 2 processes: breaking the formation with a bit and removing the <span class="hlt">drilled</span> cuttings. In rotary <span class="hlt">drilling</span>, rotational speed and weight on bit are used to control <span class="hlt">drilling</span>, and the optimization of these parameters can markedly improve <span class="hlt">drilling</span> performance. Although fluids are used for cuttings removal in terrestrial <span class="hlt">drilling</span>, most planetary <span class="hlt">drilling</span> systems conduct dry <span class="hlt">drilling</span> with an auger. Chip removal via water-ice sublimation (when excavating water-ice-bound formations at pressure below the triple point of water) and pneumatic systems are also possible. Pneumatic systems use the gas or vaporization products of a high-density liquid brought from Earth, gas provided by an in situ compressor, or combustion products of a monopropellant. <span class="hlt">Drill</span> bits can be divided into <span class="hlt">coring</span> bits, which excavate an annular shaped hole, and full-faced bits. While cylindrical <span class="hlt">cores</span> are generally superior as scientific samples, and <span class="hlt">coring</span> <span class="hlt">drills</span> have better performance characteristics, full-faced bits are simpler systems because the handling of a <span class="hlt">core</span> requires a very complex robotic mechanism. The greatest constraints to extraterrestrial <span class="hlt">drilling</span> are (1) the extreme environmental conditions, such as temperature, dust, and pressure; (2) the light-time communications delay, which necessitates highly autonomous systems; and (3) the mission and science constraints, such as mass and power budgets and the types of <span class="hlt">drilled</span> samples needed for scientific analysis. A classification scheme based on <span class="hlt">drilling</span> depth is proposed. Each of the 4 depth categories (surface <span class="hlt">drills</span>, 1-meter class <span class="hlt">drills</span>, 10-meter class <span class="hlt">drills</span>, and deep <span class="hlt">drills</span>) has distinct technological profiles and scientific ramifications. PMID:18598141</p> <div class="credits"> <p class="dwt_author">Zacny, K; Bar-Cohen, Y; Brennan, M; Briggs, G; Cooper, G; Davis, K; Dolgin, B; Glaser, D; Glass, B; Gorevan, S; Guerrero, J; McKay, C; Paulsen, G; Stanley, S; Stoker, C</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-06-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">267</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.er.usgs.gov/publication/ofr78574"> <span id="translatedtitle">Lithologic and borehole <span class="hlt">geophysical</span> data, Green Swamp area, Florida</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">Continuous unconsolidated <span class="hlt">cores</span> were obtained at 74 sites in the Green Swamp are to evaluate the potential for downward leakage to the Floridian aquifer. Depth of the <span class="hlt">core</span> holes ranged from 21 to 227 feet and averaged about 87 feet., Lithology was determined by microscopic examination of the <span class="hlt">core</span> from each hole. <span class="hlt">Geophysical</span> logs were obtained from 59 of the 74 <span class="hlt">core</span> holes. This report presents the detailed lithologic and <span class="hlt">geophysical</span> data for these <span class="hlt">core</span> holes.</p> <div class="credits"> <p class="dwt_author">Grubb, Hayes F.; Chappelear, John W.; Miller, James A.</p> <p class="dwt_publisher"></p> <p class="publishDate">1978-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">268</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/835830"> <span id="translatedtitle"><span class="hlt">GEOPHYSICAL</span> WELL LOG/<span class="hlt">CORE</span> DESCRIPTIONS, CHEROKEE AND BUG FIELDS, SAN JUAN COUNTY, UTAH, AND LITTLE UTE AND SLEEPING UTE FIELDS, MONTEZUMA COUNTY, COLORADO</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Over 400 million barrels (64 million m{sup 3}) of oil have been produced from the shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation in the Paradox Basin, Utah and Colorado. With the exception of the giant Greater Aneth field, the other 100 plus oil fields in the basin typically contain 2 to 10 million barrels (0.3-1.6 million m{sup 3}) of original oil in place. Most of these fields are characterized by high initial production rates followed by a very short productive life (primary), and hence premature abandonment. Only 15 to 25 percent of the original oil in place is recoverable during primary production from conventional vertical wells. An extensive and successful horizontal <span class="hlt">drilling</span> program has been conducted in the giant Greater Aneth field. However, to date, only two horizontal wells have been <span class="hlt">drilled</span> in small Ismay and Desert Creek fields. The results from these wells were disappointing due to poor understanding of the carbonate facies and diagenetic fabrics that create reservoir heterogeneity. These small fields, and similar fields in the basin, are at high risk of premature abandonment. At least 200 million barrels (31.8 million m{sup 3}) of oil will be left behind in these small fields because current development practices leave compartments of the heterogeneous reservoirs undrained. Through proper geological evaluation of the reservoirs, production may be increased by 20 to 50 percent through the <span class="hlt">drilling</span> of low-cost single or multilateral horizontal legs from existing vertical development wells. In addition, horizontal <span class="hlt">drilling</span> from existing wells minimizes surface disturbances and costs for field development, particularly in the environmentally sensitive areas of southeastern Utah and southwestern Colorado.</p> <div class="credits"> <p class="dwt_author">Thomas C. Chidsey Jr; David E. Eby; Laura L. Wray</p> <p class="dwt_publisher"></p> <p class="publishDate">2003-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">269</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://dx.doi.org/10.1007/s10482-009-9367-y"> <span id="translatedtitle">Description of Tessaracoccus profundi sp.nov., a deep-subsurface actinobacterium isolated from a Chesapeake impact crater <span class="hlt">drill</span> <span class="hlt">core</span> (940 m depth)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">A novel actinobacterium, designated CB31T, was isolated from a 940 m depth sample of a <span class="hlt">drilling</span> <span class="hlt">core</span> obtained from the Chesapeake meteor impact crater. The strain was isolated aerobically on R2A medium agar plates supplemented with NaCl (20 g l-1) and MgCl2???6H 2O (3 g l-1). The colonies were circular, convex, smooth and orange. Cells were slightly curved, rod-shaped in young cultures and often appeared in pairs. In older cultures cells were coccoid. Cells stained Gram-positive, were non-motile and did not form endospores. The diagnostic diamino acid of the peptidoglycan was ll-diaminopimelic acid. The polar lipids included phosphatidylglycerol, diphosphatidglycerol, four different glycolipids, two further phospholipids and one unidentified lipid. The dominant menaquinone was MK-9(H4) (70%). The major cellular fatty acid was anteiso C15:0 (83%). The DNA G + C content was 68 mol%. The strain grew anaerobically by reducing nitrate to nitrite or by fermenting glucose. It was catalase positive and oxidase negative. It grew between 10 and 45??C, with an optimum between 35 and 40??C. The pH range for growth was 5.7-9.3, with an optimum at pH 7.5. The closest phylogenetic neighbors based on 16S rRNA gene sequence identity were members of the genus Tessaracoccus (95-96% identity). On the basis of phenotypic and phylogenetic distinctiveness, strain CB31T is considered to represent a novel species of the genus Tessaracoccus, for which we propose the name Tessaracoccus profundi sp. nov.. It is the first member of this genus that has been isolated from a deep subsurface environment. The type strain is CB31T (=NCIMB 14440T = DSM 21240T). ?? 2009 Springer Science+Business Media B.V.</p> <div class="credits"> <p class="dwt_author">Finster, K. W.; Cockell, C. S.; Voytek, M. A.; Gronstal, A. L.; Kjeldsen, K. U.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">270</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://eric.ed.gov/?q=public+AND+bus&pg=6&id=EJ577182"> <span id="translatedtitle">Disaster <span class="hlt">Drill</span>.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p class="result-summary">Bus disaster <span class="hlt">drills</span> have been held all over country for years. A <span class="hlt">drill</span> in Blairsville, Pennsylvania, taught officials important lessons: (1) keep roster of students and stops in designated area on bus, and ensure emergency workers know where location; (2) send at least three school officials to accident scene; (3) provide school officials with…</p> <div class="credits"> <p class="dwt_author">Jones, Rebecca</p> <p class="dwt_publisher"></p> <p class="publishDate">1998-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">271</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://files.eric.ed.gov/fulltext/ED524982.pdf"> <span id="translatedtitle">Lockdown <span class="hlt">Drills</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p class="result-summary">As a result of House Bill 1215, introduced and passed during the 2011 North Dakota legislative session, every school building in North Dakota must conduct a lockdown <span class="hlt">drill</span>. While no timeframe, tracking or penalty was identified in the state law, the North Dakota Department of Public Instruction (DPI) advocates annual <span class="hlt">drills</span>, at a minimum, which…</p> <div class="credits"> <p class="dwt_author">North Dakota Department of Public Instruction, 2011</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">272</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2005GGG.....6.9G19W"> <span id="translatedtitle">Alteration of hyaloclastites in the HSDP 2 Phase 1 <span class="hlt">Drill</span> <span class="hlt">Core</span>: 2. Mass balance of the conversion of sideromelane to palagonite and chabazite</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Hawaii Scientific <span class="hlt">Drilling</span> Project 2 Phase 1 <span class="hlt">core</span> permits study of each stage of alteration of basalt glass during burial because stages of the process are separated vertically. Previous work has shown that alteration of hyaloclastite occurs progressively. The latest stage observed in the Phase 1 <span class="hlt">core</span> involves marginal replacement of sideromelane in shards with palagonite while simultaneously forming chabazite in pores. The basic reaction at this stage is sideromelane + components from pore waters = palagonite + chabazite + components to pore waters. Mass balance calculations show that Fe was virtually immobile in this process, being retained in palagonite. Na, Ca, Ba, P, Al, and Si were lost during palagonitization and not fully consumed in making chabazite. Mg was lost during palagonitization but retained elsewhere in smectite. K, Rb, and Sr were extracted from pore waters and enriched in the sum of the alteration products. The amount of enrichment depended upon the amount of chabazite present, which depended upon the porosity when chabazite formed. Ti, Y, U, Zr, Nb, REE, and Th were enriched in palagonite, compared to sideromelane, but were absent in chabazite. Mass balance of all phases for the entire alteration process (including earlier stages) was not possible because poorly consolidated samples do not yield accurate modal values of phases, trace element analysis of smectite was not possible, and exchange with lavas and intrusions in the succession cannot be evaluated. Calculations indicate that too little of major oxides, except Na2O, was released during palagonitization to account for the amount of smectite observed in hyaloclastites. The results of this study, and several others published in the literature, indicate that under various circumstances palagonitization will consume particular elements from pore fluid or release them to it. Such mobility implies that the hydrology of the particular system and the composition of the dissolved solids in the pore water will control whether palagonitization is a source or sink of elements. The potential exists that palagonitization of basalt glass is an important source or sink of elements for seawater and fluids circulating in the ocean crust.</p> <div class="credits"> <p class="dwt_author">Walton, Anthony W.; Schiffman, Peter; MacPherson, G. L.</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-09-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">273</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=ADA012141"> <span id="translatedtitle">Improvement of <span class="hlt">Core</span> <span class="hlt">Drill</span> Methods.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">This report documents results of a program to evaluate effectiveness of more or less conventional subsurface samplers in obtaining representative and undisturbed samples of noncohesive alluvial materials containing large quantities of gravels and cobbles....</p> <div class="credits"> <p class="dwt_author">J. L. Gatz</p> <p class="dwt_publisher"></p> <p class="publishDate">1975-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">274</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.astrobio.net/interview/1209/drilling-on-autopilot"> <span id="translatedtitle"><span class="hlt">Drilling</span> on Autopilot</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This magazine article features an interview with Mars Analog Research and Technology Experiment (MARTE) scientist Carol Stoker. In this final session of the four-part series, Stoker talks about MARTE's technology objective: developing a fully automated <span class="hlt">drilling</span> and life-detection system. Her team is <span class="hlt">drilling</span> into the pyrite subsurface of Spain's Rio Tinto in search for microbes existing in an iron-sulfur-based energy system, similar to that of Mars. She discuses the technical and monetary challenges of developing both the hardware and software for the first ever completely robotic system to do <span class="hlt">core</span> <span class="hlt">drilling</span> and sample analysis autonomously. The resource includes images from the Mars rover project, links to related web sites, and an MP3 Audio Machine text-to-speech option.</p> <div class="credits"> <p class="dwt_author">Bortman, Henry; Stoker, Carol</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-07-13</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">275</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=https://astrobiology.nasa.gov/articles/2004/09/23/drilling-on-autopilot/"> <span id="translatedtitle"><span class="hlt">Drilling</span> on Autopilot</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This magazine article features an interview with Mars Analog Research and Technology Experiment (MARTE) scientist Carol Stoker. In this final session of the four-part series, Stoker talks about MARTE's technology objective: developing a fully automated <span class="hlt">drilling</span> and life-detection system. Her team is <span class="hlt">drilling</span> into the pyrite subsurface of Spain's Rio Tinto in search for microbes existing in an iron-sulfur-based energy system, similar to that of Mars. She discuses the technical and monetary challenges of developing both the hardware and software for the first ever completely robotic system to do <span class="hlt">core</span> <span class="hlt">drilling</span> and sample analysis autonomously. The resource includes images from the Mars rover project, links to related web sites, and an MP3 Audio Machine text-to-speech option.</p> <div class="credits"> <p class="dwt_author">Bortman, Henry; Stoker, Carol; Magazine, Astrobiology</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">276</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=UCRL81901"> <span id="translatedtitle">Cross-Borehole <span class="hlt">Geophysical</span> Probing for Site Characterization.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">Ground structure is commonly estimated from <span class="hlt">core</span> samples taken from boreholes. However, knowledge of the structure exterior to the borehole can only be extrapolated from <span class="hlt">core</span> data. By using seismic and electromagnetic cross-borehole <span class="hlt">geophysical</span> probing, r...</p> <div class="credits"> <p class="dwt_author">R. J. Lytle</p> <p class="dwt_publisher"></p> <p class="publishDate">1979-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">277</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1983EOSTr..64S.443R"> <span id="translatedtitle"><span class="hlt">Drilling</span> reorganizes</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">As the first in a proposed series of steps that would move scientific ocean <span class="hlt">drilling</span> from its own niche within the National Science Foundation's (NSF) Directorate for Astronomical, Atmospheric, Earth, and Ocean Sciences (AAEO) into the agency's Division of Ocean Sciences, Grant Gross, division director, has been appointed acting director of the Office of Scientific Ocean <span class="hlt">Drilling</span> (OSOD). Gross will retain the directorship of the division, which also is part of AAEO. Allen M. Shinn, Jr., OSOD director for nearly 2 years, has been reassigned effective July 10 to a position in NSF's Office of Planning and Resource Management.The move aims to tie <span class="hlt">drilling</span> operations more closely to the science with which it is associated, Gross said. This first step is an organizational response to the current leaning toward using a commercial <span class="hlt">drilling</span> vessel as the <span class="hlt">drilling</span> platform, he said. Before the market for such commercial <span class="hlt">drill</span> ships opened (Eos, February 22, 1983, p . 73), other ship options for scientific ocean <span class="hlt">drilling</span> included refurbishing the aging Glomar Challenger or renovating, at great expense, the Glomar Explorer. A possible next step in the reorganization is to make OSOD the third section within the Ocean Sciences Division. Currently, the division is divided into the Oceanographic Facilities and Support Section and the Ocean Sciences Research Section.</p> <div class="credits"> <p class="dwt_author">Richman, Barbara T.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">278</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2002AGUFM.T71C1186M"> <span id="translatedtitle">Clay mineral analysis of the Hirabayashi NIED <span class="hlt">drill</span> <span class="hlt">core</span> on the Nojima fault that ruptured in the 1995 Kobe Earthquake, southwest Japan</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">A 1800-m-deep borehole was <span class="hlt">drilled</span> at Nojima Hirabayashi and penetrated the Nojima fault that was activated at the time of the 1995 Hyogo-ken Nanbu Earthquake (Kobe Earthquake) in Japan. Three possible fracture zones were detected at depths of about 1140 m, 1300 m, and 1800 m. At first, we analyzed the mode of distribution of rocks, minerals and chemical elements in them. There is a foliated blue-gray gouge at a depth of 1140 m. So we infer that this is the central fault plane, and began our fracture zone analysis there, as follows. The degree of fracturing is evidently greater in the hanging wall than in the footwall. We estimated the relative amounts of minerals qualitatively, and we detected not only quartz, orthoclase, plagioclase, biotite and hornblende in the parent rock (granodiorite), but also kaolinite, smectite, laumontite, stilbite, calcite, ankerite and siderite, which are related to hydrothermal alteration. Biotite notably disappears in both the hanging wall and footwall across the central fault plane, although it disappears over a significantly greater distance in the hanging wall than in the footwall. Equally, we estimated the amounts of major chemical elements quantitatively. Al2O3, Fe2O3, MnO, TiO2, and P2O5 all decrease throughout this interval, except at a few points. H2O_{ and CO2 increase throughout the interval. Na2O increases in the region adjacent to the central fault plane, while MgO and CaO increase in the hanging wall and decrease in the footwall. SiO2 and K2O decrease in the hanging wall and increase in the footwall. Next, we particularly investigated about the clay minerals such as smectite. From the <span class="hlt">drill</span> <span class="hlt">core</span>, we separated the clay-size fraction and analyzed it by X-Ray Diffractometer (XRD). Incidentally, particle-size separations are based on Stokes_fs law. We prepared oriented samples for XRD and to make it, we used the glass slide method. We measured it both in the air-dried and ethylene glycol-solvated conditions. We analyzed the other fracture zones along this fault in the same way. As a result, about the mode of distribution of rocks minerals and chemical elements, the fracture zone at 1140 m depth is very similar to the fracture zone at 1800 m depth and differs significantly from the fracture zone at 1300 m depth. But, the results of the clay minerals are different among each fracture zone. In air-dried condition, d (001) of smectite are 15 angstrom (at 1140 m depth), 14 angstrom (at 1300 m depth), 14~12 angstrom (at 1800 m depth), respectively (In ethylene glycol-solvated conditions, they are all 17 angstrom). It may suggest the existence of different fluid circulation between shallower and deeper fracture zones.</p> <div class="credits"> <p class="dwt_author">Matsuda, T.; Omura, K.; Ikeda, R.; Awaji, D.</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">279</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012AGUFM.V43B2828A"> <span id="translatedtitle">Geochemical characters of Quaternary tephra beds and their stratighraphic position in the sedimentary <span class="hlt">core</span> <span class="hlt">drilled</span> at the site U1343 in the central Bering Sea</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The project IODP exp.323 in the Bering Sea focused on analyzing long-term ocean and climate trends during 5 Ma, and <span class="hlt">drilled</span> seven sites (sites 1339-1345). Up to now, the studies of long-term tephrochronology in this area are very rare, though a part of histories of several volcanoes and late Pleistocene to Holocene volcanisms and studies for geochemistry of magma were reported in detail. Our objectives are to reveal how many widespread tephras are found in the Bering Sea and which of volcanoes or volcanic zones provided them. First of all, we analyzed forty-eight tephra samples in the sedimentary <span class="hlt">core</span> collected at site U1343, near the Bering self sloop. Sediments in site U1343 (57°33.4'N, 175°49.0'E, water depth 1956 mbsf, <span class="hlt">core</span> length 779.18 m) include three paleomagnetic events (the BM boundary;0.788 Ma, Jaramillo; 0.998 Ma, Cobb Mountain;1.173 Ma). The bottom datum event is reported as 2.0-2.2 Ma (diatom) at 716.4 m. All tephra samples were washed by flesh water and decanting, dried up naturally, sieved by the mesh of dia.250, 125 and 63 micrometer. We observed every tephra under the binocular/polarizing microscopes, and analyzed major-element composition of volcanic glass shards by EPMA (10nA, 15kV, probe dia.10 micrometer). All samples include many kinds of volcanic glass shards (color: colorless to dark brown, form: bubble-wall type, pumice type, fiber type). Diameter of grain size is normally less 125 micrometer, and volcanic glass size in some layers is concentrated in the less 63 micrometer. Thickness of tephra samples is approximately 0.5 cm to 4 cm. In the basis of geochemicalc analysis of volcanic glass shards in 48 samples, though every sample includes volcanic glass shards, we can distinguish the two groups roughly; glass-rich samples (31 samples) and contaminated samples (17 samples). Contaminated samples include course sands (lithic fragments, rounded minerals, fossil fragments), besides volcanic glass shards. Number of contaminated samples remarkably increases after BM boundary. Furthermore, during middle to late Pleistocene, the oxygen isotopic stratigraphy of benthic foranminiferal fossils in this <span class="hlt">core</span> is clear and their oscillation is wider than early Pleistocene and Pliocene. So, volcanic glass shards in 'contaminated samples' which are expected to be provided from plural sources might be transported by seasonal sea ices, and ice berg which collapsed from the ice sheet around the Beringia. On the other hand, general character and geochemistry of glass-rich samples is as follows: The size of every tephra material is under 250 micrometer and there are rarely heavy minerals. Color of tephras has many varieties (white, brown, gray, and black) by geochemistry of volcanic glass shards. Content of SiO2 in volcanic glass shards varied approximately 58-72 wt%, Na2O is ~5.2 wt%, and K2O is ~3.2 wt% (basaltic andesite, andesite, dacite, and rhyolite). There is no sample in alkali rock series, 5 samples in tholeiitic rock series and the other 26 samples in calc-alkalic rock series. Six tephra layers of 0.378Ma, 0.518-0.529Ma, 0.822-0.824Ma, 1.008Ma, 1.108Ma, and 1.547Ma are several centimeters thickness, so they are expected to be recognized as time marker beds in Bering Sea widely.</p> <div class="credits"> <p class="dwt_author">Aoki, K.; Asahi, H.; Nagatsuma, Y.; Kurihara, K.; Fukuoka, T.; Sakamoto, T.; Iijima, K.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">280</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/61287242"> <span id="translatedtitle">Sidewall <span class="hlt">core</span> gun</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">An apparatus is described for taking <span class="hlt">core</span> samples from the sidewall of a borehole in a well, the apparatus comprising: a string of <span class="hlt">drill</span> pipe; at least one gun housing connected to the downhole end of the <span class="hlt">drill</span> string; at least one <span class="hlt">coring</span> bullet radially disposed within the gun housing, the <span class="hlt">coring</span> bullet arranged for securing formation samples from the</p> <div class="credits"> <p class="dwt_author">E. A. Jr. Colle; D. N. Jr. Yates; E. F. Brieger</p> <p class="dwt_publisher"></p> <p class="publishDate">1986-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_13");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' 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onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">281</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1998LPICo.953Q...3B"> <span id="translatedtitle"><span class="hlt">Geophysical</span> Sounding</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Of the many <span class="hlt">geophysical</span> remote-sensing techniques available today, a few are suitable for the water ice-rich, layered material expected at the north martian ice cap. Radio echo sounding has been used for several decades to determine ice thickness and internal structure. Selection of operating frequency is a tradeoff between signal attenuation (which typically increases with frequency and ice temperature) and resolution (which is proportional to wavelength). Antenna configuration and size will be additional considerations for a mission to Mars. Several configurations for ice-penetrating radar systems are discussed: these include orbiter-borne sounders, sounding antennas trailed by balloons and penetrators, and lander-borne systems. Lander-borne systems could include short-wave systems capable of resolving fine structure and layering in the upper meters beneath the lander. Spread-spectrum and deconvolution techniques can be used to increase the depth capability of a radar system. If soundings over several locations are available (e.g., with balloons, rovers, or panning short-wave systems), then it will be easier to resolve internal layering, variations in basal reflection coefficient (from which material properties may be inferred), and the geometry of nonhorizontal features. Sonic sounding has a long history in oil and gas exploration. It is, however, unlikely that large explosive charges, or even swept-frequency techniques such as Vibroseis, would be suitable for a Polar lander -- these systems are capable of penetrating several kilometers of material at frequencies of 10-200 Hz, but the energy required to generate the sound waves is large and potentially destructive. The use of audio-frequency and ultrasonic sound generated by piezoelectric crystals is discussed as a possible method to explore layering and fine features in the upper meters of the ice cap. Appropriate choice of transducer(s) will permit operation over a range of fixed or modulated frequencies. Neutron scattering is used in soil science to assess the moisture content of soil. The technique relies on observing the effects of collisions between source neutrons and the H atoms in the material under test. Such a system maybe useful in assessing ice content-from within a borehole. Sounding of a several-kilometer-deep ice cap presents some considerable obstacles. There are, however, several methods that could be used to sound the upper meters of the ice cap in considerable detail.</p> <div class="credits"> <p class="dwt_author">Blake, E.</p> <p class="dwt_publisher"></p> <p class="publishDate">1998-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">282</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1988JGR....93.6077H"> <span id="translatedtitle">Hydrothermal brecciation in the Jemez fault zone, Valles Caldera, New Mexico: Results from continental Scientific <span class="hlt">Drilling</span> Program <span class="hlt">core</span> hole VC-1</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">An unusual breccia sequence penetrated in the lower 30 m of Continental Scientific <span class="hlt">Drilling</span> Program <span class="hlt">core</span> hole VC-1 (total depth 856 m) records a complex hydrothermal history culminating in hydraulic rock rupture and associated alteration at the edge of the Quaternary Valles caldera. The breccias, both tectonic and hydrothermal in origin, were formed in the Jemez fault zone, near the intersection of this major regional structure with the caldera's ring-fracture margin. Tectonic breccias in the sequence are contorted, crushed, and sheared. Coexisting hydrothermal breccias lack such frictional textures but display matrix flow foliation and prominent clast rounding, features characteristic of fluidization. These hydrothermal breccias were intensely altered, during at least five major stages, to quartz-illite-phengite-pyrite aggregates; traces of molybdenite occur locally. This assemblage indicates interaction with hydrothermal fluid at temperatures in excess of 200°C. The extrapolated present maximum temperature of 184°C in the breccia zone therefore represents considerable cooling since these phases were formed. Fluid inclusions in the breccias also preserve evidence of the prior passage of hotter fluids. The inclusions are principally two phase, liquid rich, secondary in origin, and concentrated in hydrothermal quartz. Older, high-salinity inclusions, unrelated to brecciation, homogenize in the temperature range 189°-246°C. Younger inclusions, in part of interbreccia origin, are low-salinity and homogenize in the temperature range 230°-283°C; locally coexisting liquid- and vapor-rich inclusions document periodic boiling of the dilute fluids. These fluid-inclusion data, along with the probable age of the hydrothermal breccias (<1.5 Ma), the assumed depth at which they developed (about 515 m), and the contemporaneous state of stress (extensional) can be combined to model hydrothermal brecciation at the VC-1 site. The minimum fluid pressure (Pfr) required to hydrofracture these rocks was probably about 7.5 MPa (0.0146 MPa/m). A boiling point versus depth curve based on these Pfr values graphically defines the physical conditions prevailing when the breccias were formed. When fluid pressure at the assumed depth of brecciation exceeded that curve, in response to rapid release of confining pressure possibly augmented by renewed heating, flashing hydrothermal fluid fractured the enclosing rock. Large overpressures, most likely induced by sudden seismic cracking of a hydrothermally sealed portion of the Jemez fault zone, led to local fluidization of the resulting breccias. Late quartz veining, hydrothermal alteration, and molybdenite mineralization were probably produced by the fluids responsible for brecciation.</p> <div class="credits"> <p class="dwt_author">Hulen, Jeffrey B.; Nielson, Dennis L.</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-06-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">283</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004JVGR..130...31P"> <span id="translatedtitle"><span class="hlt">Drill</span> <span class="hlt">core</span>-based facies reconstruction of a deep-marine felsic volcano hosting an active hydrothermal system (Pual Ridge, Papau New Guinea, ODP Leg 193)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Pual Ridge is a deep-marine, felsic volcanic edifice in the eastern Manus back-arc basin (Papua New Guinea) with an estimated volume of ˜6 to 9 km 3. It is 1-1.5 km wide, 20 km long and rises 500-600 m above the surrounding ocean floor. The active PACMANUS hydrothermal field on the crest of Pual Ridge at 1640-1690 m below sea level was the target of Ocean <span class="hlt">Drilling</span> Program Leg 193. Variably altered dacite lavas have been recovered from the subsurface of a low-T discharge site (Snowcap) and a high-T black smoker site (Roman Ruins) reaching a maximum depth of 380 m below seafloor (mbsf). Volcanic facies interpretation of these <span class="hlt">cores</span> is difficult due to incomplete recovery and widespread pseudoclastic textures generated by fracturing and multi-phase, incomplete fluid-dacite interaction. However, distinction of genuine volcaniclastic facies and facies with alteration-related clastic appearance is important in order to define paleo-seafloor positions within the volcanic stratigraphy, that may be prospective for massive sulfide mineralization. This has been accomplished using remnant primary characteristics indicative of transportation such as polymictic composition, grading or textural evidence for differential movement of individual clasts. Three phases of volcanic activity can be distinguished and a proximal facies association dominated by coherent facies of dacite lavas exists below Snowcap. At Roman Ruins, a medial facies association consists of lava flows with about equal proportions of coherent and volcaniclastic facies. Endogenous growth was an important process during lava flow emplacement and groundmass textures such as perlite, flow banding and spherulites indicate that cooling rates were variable, locally allowing for high-temperature devitrification. A tube pumice breccia unit is interpreted as the resedimented facies of a quench fragmented, highly vesicular dacite lava carapace. Sulfide accumulations in the subsurface are restricted to Roman Ruins suggesting that the abundance of volcaniclastic facies favored ascent of metal-bearing fluids due to the inherent high permeability. Evidence for mineralization at paleo-seafloor positions at 110 and 195 mbsf indicate a complex interrelationship between volcanic and hydrothermal activity. A facies model has been developed which may help to locate subaqueous, felsic lava-dominated volcanic centers and associated sulfide deposits in ancient volcano-sedimentary successions.</p> <div class="credits"> <p class="dwt_author">Paulick, H.; Vanko, D. A.; Yeats, C. J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-02-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">284</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5278991"> <span id="translatedtitle">Geologic report on East Chaco Canyon <span class="hlt">drilling</span> project, McKinley and San Juan Counties, New Mexico</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The East Chaco Canyon <span class="hlt">drilling</span> project of northwestern New Mexico was comprised of 15 holes <span class="hlt">drilled</span> to an average depth of 4695 feet (1431 m). These holes were <span class="hlt">drilled</span> to obtain data on extensions of the uranium producing strata of the Grants mineral belt into a deeper unexplored portion of the San Juan Basin. The goal of the project was to obtain subsurface data that would reduce the uncertainty of resource estimates of the Morrison Formation within the project area and other deeper portions of the basin. Preliminary geologic and land status studies were initiated in June 1977. <span class="hlt">Drilling</span> began in July 1978 and was completed during November 1978. A total of 70,421 feet (21,464.3 m) was <span class="hlt">drilled</span> of which 4938 feet (1505 m) was <span class="hlt">cored</span>. The <span class="hlt">cored</span> intervals included virtually all the Westwater Canyon Member and portions of the Brushy Basin and Recapture Members of the Morrison Formation. A suite of lithologic and <span class="hlt">geophysical</span> logs was obtained from each <span class="hlt">drill</span> hole. A comprehensive study of the Westwater Canyon Member <span class="hlt">core</span> from each <span class="hlt">drill</span> hole is being made by the Department of Geology of the University of New Mexico. Zones of minor uranium mineralization were encountered in both the Westwater Canyon and Brushy Basin Members of the Morrison Formation. The zones commonly occurred at the contacts between beds of altered, originally arkosic, coarse-grained, poorly sorted sandstones and finer grained sedimentary units. The best developed zone of mineralization (8 feet (2.4 m) of 0.125% eU/sub 3/O/sub 8/) occurred within a sandstone of this type that was separated from the underlying Westwater Canyon Member sandstones by about 27 feet (8.2 m) of typical Brushy Basin Member claystone.</p> <div class="credits"> <p class="dwt_author">Lease, L.W.</p> <p class="dwt_publisher"></p> <p class="publishDate">1980-05-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">285</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/5486426"> <span id="translatedtitle">Continental <span class="hlt">drilling</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The Workshop on Continental <span class="hlt">Drilling</span> was convened to prepare a report for submission to the US Geodynamics Committee with respect to the contribution that could be made by land <span class="hlt">drilling</span> to resolve major problems of geodynamics and consider the mechanisms by which the responsibility for scientific planning, establishment of priorities, administration, and budgeting for a land-<span class="hlt">drilling</span> program within the framework of the aims of the Geodynamics Project would best be established. A new and extensive program to study the continental crust is outlined in this report. The Workshop focused on the following topics: processes in the continental crust (mechanism of faulting and earthquakes, hydrothermal systems and active magma chambers); state and structure of the continental crust (heat flow and thermal structure of the crust; state of ambient stress in the North American plate; extent, regional structure, and evolution of crystalline continental crust); short hole investigations; present state and needs of <span class="hlt">drilling</span> technology; <span class="hlt">drill</span> hole experimentation and instrumentation; suggestions for organization and operation of <span class="hlt">drilling</span> project; and suggested level of effort and funding. Four recommendations are set down. 8 figures, 5 tables. (RWR)</p> <div class="credits"> <p class="dwt_author">Shoemaker, E.M. (ed.)</p> <p class="dwt_publisher"></p> <p class="publishDate">1975-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">286</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1982bsv..book.....P"> <span id="translatedtitle"><span class="hlt">Geophysical</span> fluid dynamics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Principles of fluid dynamics are applied to large-scale flows in the oceans and the atmosphere in this text, intended as a <span class="hlt">core</span> curriculum in <span class="hlt">geophysical</span> fluid dynamics. Emphasis throughout the book is devoted to basing scaling techniques and the derivation of systematic approximations to the equations of motion. The inviscid dynamics of a homogeneous fluid are examined to reveal the properties of quasi-geostrophic motion. Attention is given to density stratification as a basis for potential vorticity dynamics. Discussions are presented of Rossby waves, inertial boundary currents, the beta-plane, energy propagation, and wave interaction. Turbulent mixing is mentioned in the context of large-scale flows. The use of the homogeneous model in investigating wind-driven ocean circulation is demonstrated, and the quasi-geostrophic dynamics of a stratified fluid are studied for a flow on a sphere. Finally, instability theory is exposed as a fundamental concept for dynamic meteorology and ocean dynamics.</p> <div class="credits"> <p class="dwt_author">Pedlosky, J.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">287</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/787164"> <span id="translatedtitle"><span class="hlt">Geophysics</span> with applications to subsurface waste disposal: Case history</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Recent development in <span class="hlt">geophysical</span> methods allows us to accurately map the distribution of seismic velocity, density and electrical conductivity beneath the surface and between boreholes. These physical properties are dependent on porosity, fluid saturation, fluid conductivity, pressure, temperature, clay content, and in some circumstances, permeability. Hydrological parameters may be measured or inferred from <span class="hlt">drill</span> hole experiments or directly from <span class="hlt">core</span> samples. The point measurements in a <span class="hlt">drill</span> hole are then interpolated to the interwell volume using either statistical properties of the local geology or reasonable estimates of the geological structure and lithology. More direct evidence is obtained from well tests, and interference tests between multiple wells, but these are ill posed inverse problems when it comes to defining the properties of the entire interwell volume. Furthermore such tests are impossible in the vadose zone. The interpolation of well data is often inaccurate or misleading and the central problem for all these studies is the lack of these fundamental parameters throughout the subsurface volume of interest.</p> <div class="credits"> <p class="dwt_author">Lee, K.H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2001-08-09</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">288</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012EGUGA..14.5807J"> <span id="translatedtitle">> Exploring the Scandinavian Mountain Belt by Deep <span class="hlt">Drilling</span> (COSC)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Collisional Orogeny in the Scandinavian Caledonides (COSC) project proposes to <span class="hlt">drill</span> two fully <span class="hlt">cored</span> scientific boreholes, both to c. 2.5 km depth, in the Swedish Caledonides, one near the town of Åre (COSC 1) and the other further east (COSC 2). Together they will provide a c. 5 km deep high-resolution mid-crustal section through this major mid-Palaeozoic orogen. Main project objectives include (i) improved understanding of mountain building processes (orogeny), (ii) investigation of the geothermal gradient and its response to palaeoclimatic influences, (iii) the hydrogeological-hydrochemical state of the mountain belt, (iv) the deep biosphere in the metamorphic rocks and crystalline basement, and (v) calibration of surface <span class="hlt">geophysics</span> and geology. The Caledonide Orogen is comparable in size and many other respects to today's Himalayan mountain belt. Silurian collision with underthrusting of the paleo-continent Baltica below Laurentia resulted in widespread formation of eclogite. Major allochthons were transported many hundreds of kilometers onto the Baltoscandian Platform, including high-grade metamorphic rocks and migmatites which were generated during continental margin subduction and emplaced ductilely at mid-crustal levels. COSC will provide detailed insight into mid-Palaeozoic mountain building processes and further our understanding of past, present and future orogen dynamics. Located in a key-area for Caledonian geology, it is close to a major <span class="hlt">geophysical</span> transect across the mountain belt which has been complemented recently with high-resolution reflection seismics and aerogeophysics for site-selection. The COSC research program is being developed by five working groups, geology, <span class="hlt">geophysics</span>, geothermics, hydrogeology and microbiology. It has direct relevance for society by improving our understanding of mountain building processes, hydrological-hydrochemical regimes in mountain areas and Precambrian shields, deep subsurface conditions for underground engineering, ore genesis and assessment of geothermal potential. After a general scientific workshop supported by ICDP in 2010, the hydrogeological aspects of deep <span class="hlt">drilling</span> were the topic of a separate workshop last year; orogen dynamics will provide a focus at EGU; and geothermics research will be addressed at a workshop in Autumn 2012. The geothermics workshop will be announced on the ICDP homepage. Partial funding for the <span class="hlt">drilling</span> has been achieved through national sources and ICDP. Additional funding (c. 500000€) is being sought to allow <span class="hlt">drilling</span> to commence in 2013. Scientific and financial partners, both from academia and industry, are welcome to the project. The presentation will review the current status of the COSC project and the research leading up to the site selection for COSC 1.</p> <div class="credits"> <p class="dwt_author">Juhlin, C.; Gee, D. G.; Lorenz, H.; Pascal, C.; Pedersen, K.; Tsang, C.-F.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">289</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20100028086&hterms=ultrasonic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dultrasonic"> <span id="translatedtitle">Ultrasonic rotary-hammer <span class="hlt">drill</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p class="result-summary">A mechanism for <span class="hlt">drilling</span> or <span class="hlt">coring</span> by a combination of sonic hammering and rotation. The <span class="hlt">drill</span> includes a hammering section with a set of preload weights mounted atop a hammering actuator and an axial passage through the hammering section. In addition, a rotary section includes a motor coupled to a drive shaft that traverses the axial passage through the hammering section. A <span class="hlt">drill</span> bit is coupled to the drive shaft for <span class="hlt">drilling</span> by a combination of sonic hammering and rotation. The <span class="hlt">drill</span> bit includes a fluted shaft leading to a distal crown cutter with teeth. The bit penetrates sampled media by repeated hammering action. In addition, the bit is rotated. As it rotates the fluted bit carries powdered cuttings helically upward along the side of the bit to the surface.</p> <div class="credits"> <p class="dwt_author">Bar-Cohen, Yoseph (Inventor); Badescu, Mircea (Inventor); Sherrit, Stewart (Inventor); Bao, Xiaoqi (Inventor); Kassab, Steve (Inventor)</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">290</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5666867"> <span id="translatedtitle">The Toa Baja <span class="hlt">Drilling</span> Project, Puerto Rico: Scientific <span class="hlt">drilling</span> into a non-volcanic island arc massif</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The Toa Baja <span class="hlt">Drilling</span> Project was a broad, interdisciplinary experiment to document the in situ geology and <span class="hlt">geophysics</span> of a non-volcanic island arc massif. This overview provides a brief summary of oil exploration on Puerto Rico that lead up to the present investigation, and summarizes some of the problems addressed by <span class="hlt">drilling</span>.</p> <div class="credits"> <p class="dwt_author">Larue, D.K. (Univ. of Puerto Rico, Mayaguez (Puerto Rico))</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-03-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">291</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004JGE.....1......"> <span id="translatedtitle">EDITORIAL: The interface between <span class="hlt">geophysics</span> and engineering</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Journal of <span class="hlt">Geophysics</span> and Engineering (JGE) aims to publicize and promote research and developments in <span class="hlt">geophysics</span> and in related areas of engineering. As stated in the journal scope, JGE is positioned to bridge the gap between earth physics and geo-engineering, where it reflects a growing trend in both industry and academia. JGE covers those aspects of engineering that bear closely on <span class="hlt">geophysics</span> or on the targets and problems that <span class="hlt">geophysics</span> addresses. Typically this will be engineering focused on the subsurface, particularly petroleum engineering, rock mechanics, <span class="hlt">geophysical</span> software engineering, <span class="hlt">drilling</span> technology, remote sensing, instrumentation and sensor design. There is a trend, visible throughout academia, for rapid expansion in cross-disciplinary, multi-disciplinary and inter-disciplinary working. Many of the most important and exciting problems and advances are being made at the boundaries between traditional subject areas and, increasingly, techniques from one discipline are finding applications in others. There is a corresponding increasing requirement for researchers to be aware of developments in adjacent areas and for papers published in one area to be readily accessible, both in terms of location and language, to those in others. One such area that is expanding rapidly is that at the interface between <span class="hlt">geophysics</span> and engineering. There are three principal developments. <span class="hlt">Geophysics</span>, and especially applied <span class="hlt">geophysics</span>, is increasingly constrained by the limits of technology, particularly computing technology. Consequently, major advances in <span class="hlt">geophysics</span> are often predicated upon major developments in engineering and many research geophysicists are working in multi-disciplinary teams with engineers. Engineering problems relevant to the sub-surface are increasingly looking to advances in <span class="hlt">geophysics</span> to provide part of the solution. Engineering systems, for example, for tunnel boring or petroleum reservoir management, are using high-resolution <span class="hlt">geophysical</span> imaging to reduce uncertainty and associated risk. In the economically dominant area of petroleum exploration and production, the focus has moved dramatically from exploration to production. This shift is leading increasingly to integration between petroleum geoscience and petrophysics on the one hand, and petroleum engineering and rock mechanics on the other. This integration means that petroleum engineers need to be aware of developments in <span class="hlt">geophysics</span>, and geophysicists need to be aware of the problems and requirements of the reservoir engineer. Journal of <span class="hlt">Geophysics</span> and Engineering has been established firmly in that context, and we expect this trend to strengthen and extend far into the future. The Editors welcome your submissions, and comments on this first issue of JGE.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2004-03-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">292</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ulapland.fi/home/hkunta/jmoore/pdfs/Isaksson42A073.pdf"> <span id="translatedtitle">ice <span class="hlt">core</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Svalbard ice <span class="hlt">cores</span> have not yet been fully exploited for studies of climate and environmental conditions. In one recently <span class="hlt">drilled</span> ice <span class="hlt">core</span> from Lomonosovfonna we have studied the methanesulphonic acid (MSA) records in relation to temperature and sea ice. During the present climatic conditions MSA appears to be negatively correlated with the sea ice conditions in the Barents Sea, and</p> <div class="credits"> <p class="dwt_author">Elisabeth Isaksson; Teija Kekonen; John Moore</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">293</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.usgs.gov/of/2007/1094/"> <span id="translatedtitle">Site Report for USGS Test Holes <span class="hlt">Drilled</span> at Cape Charles, Northampton County, Virginia, in 2004</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">The U.S. Geological Survey <span class="hlt">drilled</span> two test holes near Cape Charles, Virginia, during May and June 2004, as part of an investigation of the buried, late Eocene Chesapeake Bay impact structure. The first hole is designated as the USGS-Sustainable Technology Park test hole #1 (USGS-STP1). This test hole was abandoned at a depth of 300 ft; cuttings samples were collected, but no <span class="hlt">cores</span> or <span class="hlt">geophysical</span> logs were acquired. The second hole is designated as the USGS-Sustainable Technology Park test hole #2 (USGS-STP2). This test hole was <span class="hlt">drilled</span> to a depth of 2,699 ft. <span class="hlt">Cores</span> were collected between depths of 1,401.7 ft and 1,420.7 ft and between 2,440.0 ft and 2,699.0 ft. Cuttings samples were collected from the uncored intervals below 280-ft depth. Interim sets of <span class="hlt">geophysical</span> logs were acquired during the <span class="hlt">drilling</span> operation, and one final set was acquired at the end of <span class="hlt">drilling</span>. Two wells were installed in the USGS-STP2 test hole. The deep well (designated 62G-24) was screened between 2,260 ft and 2,280 ft, and the shallow well (designated 62G-25) was screened between 1,360 ft and 1,380 ft. Ground-water salinities stabilized at 40 parts per thousand for the deep well and 20 parts per thousand for the shallow well. The geologic section encountered in the test holes consists of three main units: (1) Eocene, Oligocene, Miocene, Pliocene, and Pleistocene sands and clays are present between land surface and a depth of 1,163 ft; (2) sediment-clast breccias of the impact structure are present between depths of 1,163 ft and 2,150 ft; and (3) crystalline-clast breccias and cataclastic gneiss of the impact structure are present between depths of 2,150 ft and 2,699 ft.</p> <div class="credits"> <p class="dwt_author">Gohn, Gregory S.; Sanford, Ward E.; Powars, David S.; Horton, J. Wright, Jr.; Edwards, Lucy E.; Morin, Roger H.; Self-Trail, Jean M.</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">294</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2005AGUFM.C11A1064S"> <span id="translatedtitle">Scientific <span class="hlt">Drilling</span> into Deep Permafrost: An International Polar Year Proposal</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Various estimates suggest that permafrost covers approximately 20% of the terrestrial surface of the earth. Despite its widespread occurrence, the history of permafrost formation during the Quaternary, its physical and <span class="hlt">geophysical</span> properties, permafrost microbiology, the existence of hydrates, and the significance of permafrost as a source and sink of greenhouse gases are all poorly understood. This is particularly true for `deep' permafrost (below about 50 m to as much as 1500 m) as no modern, well constrained geological research wells have been completed worldwide. As part of the International Polar Year, we are proposing a scientific <span class="hlt">drilling</span> program to fill a significant gap in knowledge about deep permafrost by advancing a wide range of <span class="hlt">core</span> and <span class="hlt">geophysical</span> studies, extensive borehole monitoring, and focussed modelling studies. Some of the key scientific tasks will: Identify and quantify the abundance of a variety of greenhouse gases (both hydrocarbon gases but also gases such as CO2) existing as free gas, gas dissolved in unfrozen water, and in clathrate hydrate form. Ascertain the sources of these gases and specify transport pathways through permafrost with particular emphasis on surface fluxes to the atmosphere. Quantify the distribution and concentration of microbial communities within deep permafrost. Determine the petrophysical, geomechanical, and <span class="hlt">geophysical</span> properties of the deep permafrost. Document the geothermal regime of deep permafrost, model its evolution during the Quaternary period, and ascertain how it is changing with time as a result of a changing global environment. Document the unique hydrologic regime of deep permafrost including the occurrence of deep taliks or unfrozen zones. Assess terrestrial permafrost as an analogue to the Martian subsurface. Upon completion of these initial studies, we intend to utilize the well bores as long-term <span class="hlt">geophysical</span> and hydrological observatories. We anticipate that these activities could be integrated with other observations of long-term climatic and/or physical/environmental phenomena.</p> <div class="credits"> <p class="dwt_author">Schmitt, D. R.; Dallimore, S. R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">295</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2008AGUFM.V41B2069E"> <span id="translatedtitle">The Iceland Deep <span class="hlt">Drilling</span> Project (IDDP): (I) <span class="hlt">Drilling</span> for Supercritical Hydrothermal Fluids is Underway</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The IDDP is being carried out by an international industry-government consortium in Iceland (consisting of three leading Icelandic power companies, together with the National Energy Authority), Alcoa Inc. and StatoilHydro) with the objective of investigating the economic feasibility of producing electricity from supercritical geothermal fluids. This will require <span class="hlt">drilling</span> to temperatures of 400-600°C and depths of 4 to 5 km. Modeling suggests that supercritical water could yield an order of magnitude greater power output than that produced by conventional geothermal wells. The consortium plans to test this concept in three different geothermal fields in Iceland. If successful, major improvements in the development of high-temperature geothermal resources could result worldwide. In June 2008 preparation of the first deep IDDP well commenced in the Krafla volcanic caldera in the active rift zone of NE Iceland. Selection of the first <span class="hlt">drill</span> site for this well was based on geological, <span class="hlt">geophysical</span> and geochemical data, and on the results of extensive geothermal <span class="hlt">drilling</span> since 1971. During 1975-1984, a rifting episode occurred in the caldera, involving 9 volcanic eruptions. In parts of the geothermal field acid volcanic gases made steam from some of the existing wells unsuitable for power generation for the following decade. A large magma chamber at 3-7 km depth was detected by S-wave attenuation beneath the center of the caldera, believed to be the heat source of the geothermal system. A recent MT-survey has confirmed the existence of low resistivity bodies at shallow depths within the volcano. The IDDP well will be <span class="hlt">drilled</span> and cased to 800m depth in September, before the winter snows, and in spring 2009 it will be <span class="hlt">drilled</span> and cased to 3.5km depth and then deepened to 4.5 km in July. Several spot <span class="hlt">cores</span> for scientific studies will be collected between 2400m and the total depth. After the well heats, it will be flow tested and, if successful, a pilot plant for power production should follow in 2010. During 2009-19 two new wells, ~4 km deep, will be <span class="hlt">drilled</span> at the Hengill and the Reykjanes geothermal fields in southern Iceland, and subsequently deepened into the supercritical zone. In contrast to the fresh water systems at Krafla and Hengill, the Reykjanes geothermal system produces hydrothermally modified seawater on the Reykjanes peninsula, where the Mid-Atlantic Ridge comes on land. Processes at depth at Reykjanes should be more similar to those responsible for black smokers on oceanic rift systems. Because of the considerable international scientific opportunities afforded by the IDDP, the US National Science Foundation and the International Continental Scientific <span class="hlt">Drilling</span> Program will jointly fund the <span class="hlt">coring</span> and sampling for scientific studies. Research is underway on samples from existing wells in the targeted geothermal fields, and on active mid-ocean ridge systems that have conditions believed to be similar to those that will be encountered in deep <span class="hlt">drilling</span> by the IDDP. Some of these initial scientific studies by US investigators are reported in the accompanying papers.</p> <div class="credits"> <p class="dwt_author">Elders, W. A.; Fridleifsson, G. O.; Bird, D. K.; Reed, M. H.; Schiffman, P.; Zierenberg, R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">296</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19940004521&hterms=diamond+mining&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Ddiamond%2Bmining"> <span id="translatedtitle">Lunar deep <span class="hlt">drill</span> apparatus</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p class="result-summary">Proposed as a baseline configuration, this rotary <span class="hlt">drill</span> apparatus is designed to produce 100-mm diameter holes in the lunar surface at depths up to 50 meters. The <span class="hlt">drill</span> is intended to acquire samples for scientific analysis, mineral resource location, calibration of electronic exploration devices, and foundation analysis at construction sites. It is also intended to prepare holes for emplacement of scientific instruments, the setting of structural anchors, and explosive methods in excavation and mining activities. Defined as a deep <span class="hlt">drill</span> because of the modular <span class="hlt">drill</span> string, it incorporates an automatic rod changer. The apparatus is teleoperated from a remote location, such as earth, utilizing supervisory control techniques. It is thus suitable for unmanned and man-tended operation. Proven terrestrial <span class="hlt">drilling</span> technology is used to the extent it is compatible with the lunar environment. Augers and drive tubes form holes in the regolith and may be used to acquire loose samples. An inertial cutting removal system operates intermittently while rock <span class="hlt">core</span> <span class="hlt">drilling</span> is in progress. The apparatus is carried to the work site by a three-legged mobile platform which also provides a 2-meter feed along the hole centerline, an off-hole movement of approximately .5 meters, an angular alignment of up to 20 deg. from gravity vertical, and other dexterity required in handling rods and samples. The technology can also be applied using other carriers which incorporate similar motion capabilities. The apparatus also includes storage racks for augers, rods, and ancillary devices such as the foot-plate that holds the down-hole tooling during rod changing operations.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">1989-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">297</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/399666"> <span id="translatedtitle">Geology of the USW SD-7 <span class="hlt">drill</span> hole Yucca Mountain, Nevada</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The USW SD-7 <span class="hlt">drill</span> hole is one of several holes <span class="hlt">drilled</span> under Site Characterization Plan Study 8.3.1.4.3.1, also known as the Systematic <span class="hlt">Drilling</span> Program, as part of the U.S. Department of Energy characterization program at Yucca Mountain, Nevada. The Yucca Mountain site has been proposed as the potential location of a repository for high-level nuclear waste. The SD-7 <span class="hlt">drill</span> hole is located near the southern end of the potential repository area and immediately to the west of the Main Test Level drift of the Exploratory Studies Facility. The hole is not far from the junction of the Main Test Level drift and the proposed South Ramp decline. <span class="hlt">Drill</span> hole USW SD-7 is 2675.1 ft (815.3 m) deep, and the <span class="hlt">core</span> recovered nearly complete sections of ash-flow tuffs belonging to the lower half of the Tiva Canyon Tuff, the Pah Canyon Tuff, and the Topopah Spring Tuff, all of which are part of the Miocene Paintbrush Group. <span class="hlt">Core</span> was recovered from much of the underlying Calico Hills Formation, and <span class="hlt">core</span> was virtually continuous in the Prow Pass Tuff and the Bullfrog Tuff. The SD-7 <span class="hlt">drill</span> hole penetrated the top several tens of feet into the Tram Tuff, which underlies the Prow Pass and Bullfrog Tuffs. These latter three units are all formations of the Crater Flat Group, The <span class="hlt">drill</span> hole was collared in welded materials assigned to the crystal-poor middle nonlithophysal zone of the Tiva Canyon Tuff; approximately 280 ft (85 m) of this ash-flow sheet was penetrated by the hole. The Yucca Mountain Tuff appears to be missing from the section at the USW SD-7 location, and the Pah Canyon Tuff is only 14.5 ft thick. The Pah Canyon Tuff was not recovered in <span class="hlt">core</span> because of <span class="hlt">drilling</span> difficulties, suggesting that the unit is entirely nonwelded. The presence of this unit is inferred through interpretation of down-hole <span class="hlt">geophysical</span> logs.</p> <div class="credits"> <p class="dwt_author">Rautman, C.A. [Sandia National Laboratories, Albuquerque, NM (United States); Engstrom, D.A. [Spectra Research Inst., Albuquerque, NM (United States)</p> <p class="dwt_publisher"></p> <p class="publishDate">1996-09-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">298</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFM.T54D..02Y"> <span id="translatedtitle">Scientific <span class="hlt">Drilling</span> on the Diamond-Bearing Luobusa Ophiolite, Tibet</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The "Selecting Continental Scientific <span class="hlt">Drilling</span> Sites and Experimenting with <span class="hlt">Drilling</span> Technology Project" is the fifth project of the SinoProbe Program (SinoProbe-5). This project will focus on 7 critical tectonic and mineral resource regions, including the Jinchuan Cu-Ni sulfide deposits in Gansu province, the Luobusa ophiolite in Tibet, the Tengchong volcano-thermal tectonic zone in Yunnan, the boundary of the North China and South China blocks in the Laiyang basin of Shandong province, the Yudu-Ganxian polymetallic deposits in Jiangxi province, the Tongling polymetallic deposit and the Luzhong volcanic basin and mineral deposit district in Anhui province. Scientific <span class="hlt">drilling</span>, along with geological and <span class="hlt">geophysical</span> investigations, will help to reveal the composition and structure of the continental crust, verify the results of <span class="hlt">geophysical</span> explorations and establish standards for deep <span class="hlt">geophysical</span> exploration. On the basis of pilot-hole <span class="hlt">drilling</span>, surface studies and <span class="hlt">geophysical</span> investigations, the Luobusa scientific <span class="hlt">drilling</span> project is focused on the Luobusa ophiolitic diamond-bearing ultramafic massif along the Yarlung-Zangbo suture between the Indian and Eurasia plates. The main purposes of this work are to investigate the distribution and conditions of formation UHP mantle minerals and podiform chromitites in ophiolites and to develop prospecting criteria for ophiolite-type chromite deposits. The Luobusa pilot-hole (LBS-ZK1) was completed in 2010 to a depth of 1478.8 m with an average <span class="hlt">core</span> recovery of 93.6%. The second hole (LBS-ZK2) reached a depth of 967.5 m on August 1, 2011 with an average <span class="hlt">core</span> recovery of about 90%. The ultimate target depth for this hole is 2000 m. Hole LBS-ZK2 penetrated 70 m of Triassic sandstone, marble and chlorite schist strata above the ultramafic body. The contact between the two is a fault marked by extensive shearing and serpentinization but lacking evidence of thermal metamorphism. A preliminary profile of the ultramafic rocks in hole LBS-ZK1 shows that the sequence can be subdivided into three main sections. The first 1260 m consist chiefly of harzburgite with minor dunite, representing a depleted mantle sequence. The lower part of this sequence (from 890 m to 1260 m) is highly serpentinized. The second sequence, from 1260 m to 1414 m, consists mainly of dunite with minor harzburgite, probably representing a cumulate ultramafic section. From 1414 m to the base of the hole is a 350-m-thick sequence of cumulate gabbro. The presence of gabbro beneath the ultramafic rocks without a fault contact supports the interpretation that the entire sequence has been overturned, as suggested by earlier field studies. Detailed studies in mineralogy, petrology, geochemistry and isotope dating are undergoing and will be basically presented.</p> <div class="credits"> <p class="dwt_author">Yang, J.; Li, J.; Xu, X.; Ba, D.; Li, Z.; Li, Y.; Zhao, L.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">299</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=DE97005377"> <span id="translatedtitle"><span class="hlt">Core</span>-tube data logger.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">Wireline <span class="hlt">core</span> <span class="hlt">drilling</span>, increasingly used for geothermal exploration, employs a <span class="hlt">core</span>-tube to capture a rock <span class="hlt">core</span> sample during <span class="hlt">drilling</span>. Three types of <span class="hlt">core</span>-tube data loggers (CTDL) have been built and tested to date by Sandia national Laboratories. They ...</p> <div class="credits"> <p class="dwt_author">J. A. Henfling R. A. Normann S. Knudsen D. Drumheller</p> <p class="dwt_publisher"></p> <p class="publishDate">1997-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">300</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.er.usgs.gov/publication/70023989"> <span id="translatedtitle">Spatial scale analysis in <span class="hlt">geophysics</span> - Integrating surface and borehole <span class="hlt">geophysics</span> in groundwater studies</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">Integration of <span class="hlt">geophysical</span> data obtained at various scales can bridge the gap between localized data from boreholes and site-wide data from regional survey profiles. Specific approaches to such analysis include: 1) comparing <span class="hlt">geophysical</span> measurements in boreholes with the same measurement made from the surface; 2) regressing <span class="hlt">geophysical</span> data obtained in boreholes with water-sample data from screened intervals; 3) using multiple, physically independent measurements in boreholes to develop multivariate response models for surface <span class="hlt">geophysical</span> surveys; 4) defining subsurface cell geometry for most effective survey inversion methods; and 5) making <span class="hlt">geophysical</span> measurements in boreholes to serve as independent verification of <span class="hlt">geophysical</span> interpretations. Integrated analysis of surface electromagnetic surveys and borehole <span class="hlt">geophysical</span> logs at a study site in south Florida indicates that salinity of water in the surficial aquifers is controlled by a simple wedge of seawater intrusion along the coast and by a complex pattern of upward brine seepage from deeper aquifers throughout the study area. This interpretation was verified by <span class="hlt">drilling</span> three additional test boreholes in carefully selected locations.</p> <div class="credits"> <p class="dwt_author">Paillet, F. L.</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_14");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' 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onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">301</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40425734"> <span id="translatedtitle">The heavy mineral record in the Pliocene to Quaternary sediments of the CIROS-2 <span class="hlt">drill</span> <span class="hlt">core</span>, McMurdo Sound, Antarctica</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The heavy mineral assemblages of the Lower Pliocene to Quaternary glacial sediments of the CIROS-2 <span class="hlt">drill</span> site, situated near the mouth of Ferrar Glacier on the McMurdo Sound shelf, Antarctica, were analysed by optical means in order to reconstruct the source areas and dynamics of the late Cenozoic Antarctic ice masses. The assemblages are dominated by pyroxenes, amphiboles, altered minerals</p> <div class="credits"> <p class="dwt_author">Werner Ehrmann; Kerstin Polozek</p> <p class="dwt_publisher"></p> <p class="publishDate">1999-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">302</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009EGUGA..11.5073F"> <span id="translatedtitle">Advantages and limitations of remotely operated sea floor <span class="hlt">drill</span> rigs</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">A variety of research targets in marine sciences including the investigation of gas hydrates, slope stability, alteration of oceanic crust, ore formation and palaeoclimate can be addressed by shallow <span class="hlt">drilling</span>. However, <span class="hlt">drill</span> ships are mostly used for deep <span class="hlt">drillings</span>, both because the effort of building up a <span class="hlt">drill</span> string from a <span class="hlt">drill</span> ship to the deep sea floor is tremendous and control on <span class="hlt">drill</span> bit pressure from a movable platform and a vibrating <span class="hlt">drill</span> string is poor especially in the upper hundred meters. During the last decade a variety of remotely operated <span class="hlt">drill</span> rigs have been developed, that are deployed on the sea bed and operated from standard research vessels. These developments include the BMS (Bentic Multicoring System, developed by Williamson and Associates, operated by the Japanese Mining Agency), the PROD (Portable Remotely Operated <span class="hlt">Drill</span>, developed and operated by Benthic Geotech), the Rockdrill 2 (developed and operated by the British geological Survey) and the MeBo (German abbreviation for sea floor <span class="hlt">drill</span> rig, developed and operated by Marum, University of Bremen). These <span class="hlt">drill</span> rigs reach <span class="hlt">drilling</span> depths between 15 and 100 m. For shallow <span class="hlt">drillings</span> remotely operated <span class="hlt">drill</span> rigs are a cost effective alternative to the services of <span class="hlt">drill</span> ships and have the major advantage that the <span class="hlt">drilling</span> operations are performed from a stable platform independent of any ship movements due to waves, wind or currents. Sea floor <span class="hlt">drill</span> rigs can be deployed both in shallow waters and the deep sea. A careful site survey is required before deploying the sea floor <span class="hlt">drill</span> rig. Slope gradient, small scale topography and soil strength are important factors when planning the deployment. The choice of <span class="hlt">drill</span> bits and <span class="hlt">core</span> catcher depend on the expected geology. The required <span class="hlt">drill</span> tools are stored on one or two magazines on the <span class="hlt">drill</span> rig. The MeBo is the only remotely operated <span class="hlt">drill</span> rig world wide that can use wire line <span class="hlt">coring</span> technique. This method is much faster than conventional <span class="hlt">drilling</span>. It has the advantage that the <span class="hlt">drill</span> string stays in the <span class="hlt">drilled</span> hole during the entire <span class="hlt">drilling</span> process and prevents the <span class="hlt">drilled</span> hole from collapsing while the inner <span class="hlt">core</span> barrels comprising the <span class="hlt">drilled</span> <span class="hlt">core</span> sections are hooked up inside the <span class="hlt">drill</span> string using a wire.</p> <div class="credits"> <p class="dwt_author">Freudenthal, T.; Smith, D. J.; Wefer, G.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">303</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFMOS13A1166E"> <span id="translatedtitle">The Iceland Deep <span class="hlt">Drilling</span> Project (IDDP):(I) <span class="hlt">Drilling</span> at Krafla encountered Rhyolitic Magma</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The IDDP aims to produce supercritical hydrothermal fluids from depths of 4-5 km and temperatures of >400°C as modeling suggests that supercritical water could generate an energy output about 10 times that of a typical geothermal well. This could lead to major improvements in developing high-temperature geothermal resources worldwide. The first IDDP well was located in the Krafla caldera in the active central rift zone of NE Iceland, where during 1975-1984, a rifting episode occurred that involved 9 distinct volcanic eruptions. At Krafla there has been extensive production <span class="hlt">drilling</span> since 1971 to supply steam to a geothermal power plant. Within the caldera a large magma chamber was detected by S-wave attenuation at 3-7 km depth, and a recent MT-survey determined its location. The IDDP-1 was located to reach to 4.5 km to end above the magma chamber. When the <span class="hlt">drilling</span> had reached 2075 m depth multiple <span class="hlt">drilling</span> problems ensued, including a failed <span class="hlt">coring</span> attempt, twist offs, and sidetracks to bypass <span class="hlt">drill</span> string lost in the hole. An anchor casing was set at 1950 m to case off the trouble zones. However <span class="hlt">drilling</span> problems continued and another twist off and sidetrack followed. <span class="hlt">Drilling</span> then penetrated a mixture of fresh basalt and granophyre until 24th June 2009, when at about 2100 m the bit became stuck. However, circulation was maintained and rhyolitic glass was returned to the surface. Rhyolitic magma flowed into the <span class="hlt">drill</span> hole filling the bottom 10 m. The glass cuttings returned were at first pumiceous then homogeneous, sparsely phyric obsidian. The petrology of this glass is described in accompanying posters. The intrusion responsible was evidently below the resolution of available <span class="hlt">geophysical</span> surveys. We decided to terminate <span class="hlt">drilling</span> and test the well and so a 9 5/8 inch sacrificial production casing was cemented inside the anchor casing with a 9 5/8 inch slotted liner below. The well is now heating, and will be flow tested in late November 2009. If the flow tests are successful, a pilot plant to test power production could follow in 2010. The IDDP has engendered considerable scientific interest. Some of the research underway on samples from the IDDP-1 and from other wells at Krafla and from wells in the Reykjanes geothermal field, also targeted by the IDDP, is reported in accompanying posters. Subject to funding, two new IDDP wells, >4 km deep, are to be <span class="hlt">drilled</span> at the Hengill and the Reykjanes geothermal fields during 2010-2012 to search for supercritical fluid. In contrast to the fresh water systems at Krafla and Hengill, the Reykjanes geothermal system in SW Iceland, on the landward extension of the mid-Atlantic Ridge, produces hydrothermally modified seawater. Processes at depth at Reykjanes should be quite similar to those responsible for black smokers on oceanic rift systems.</p> <div class="credits"> <p class="dwt_author">Elders, W. A.; Fridleifsson, G. O.; Mortensen, A.; Gudmunsson, A.; Gudmundsson, B.; Bird, D. K.; Reed, M. H.; Schiffman, P.; Zierenberg, R. A.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">304</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/11557253"> <span id="translatedtitle">Chlorinated hydrocarbon pesticides and polychlorinated biphenyls in sediment <span class="hlt">cores</span> from San Francisco Bay 1 Institute of <span class="hlt">Geophysics</span> and Planetary Physics Contribution Number: 4214. 1</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Sediment <span class="hlt">cores</span> of known chronology from Richardson and San Pablo Bays in San Francisco Bay, CA, were analyzed for a suite of chlorinated hydrocarbon pesticides and polychlorinated biphenyls to reconstruct a historic record of inputs. Total DDTs (DDT=2,4?- and 4,4?-dichlorodiphenyltrichloroethane and the metabolites, 2,4?- and 4,4?-DDE, -DDD) range in concentration from 4–21 ng\\/g and constitute a major fraction (>84%) of</p> <div class="credits"> <p class="dwt_author">M. I. Venkatesan; R. P. de Leon; A. van Geen; S. N. Luoma</p> <p class="dwt_publisher"></p> <p class="publishDate">1999-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">305</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=PB95243853"> <span id="translatedtitle"><span class="hlt">Geophysical</span> Exploration Methods. MP1600.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary"><span class="hlt">Geophysics</span> is the science which occupies itself with the study of naturally occurring phenomena of the earth. Exploration <span class="hlt">geophysics</span> is that part of <span class="hlt">geophysics</span> that occupies itself with the application of <span class="hlt">geophysical</span> methods to the discovery and evaluatio...</p> <div class="credits"> <p class="dwt_author">G. G. Drijkoningen</p> <p class="dwt_publisher"></p> <p class="publishDate">1994-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">306</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.gpo.gov:80/fdsys/pkg/CFR-2014-title15-vol3/pdf/CFR-2014-title15-vol3-sec950-5.pdf"> <span id="translatedtitle">15 CFR 950.5 - National <span class="hlt">Geophysical</span> and Solar-Terrestrial Data Center (NGSDC).</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href=""></a></p> <p class="result-summary">...Data Center-A (Solid-Earth <span class="hlt">Geophysics</span>, Solar Terrestrial Physics, and Glaciology). (a) <span class="hlt">Geophysical</span> and solar-terrestrial...<span class="hlt">cores</span>, samples, and sediments. (2) Solar-Terrestrial physics. Ionosphere data, including ionograms, frequency...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2014-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">307</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20130014134&hterms=TOE&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DTOE"> <span id="translatedtitle">Microgravity <span class="hlt">Drill</span> and Anchor System</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p class="result-summary">This work is a method to <span class="hlt">drill</span> into a rock surface regardless of the gravitational field or orientation. The required weight-on-bit (WOB) is supplied by a self-contained anchoring mechanism. The system includes a rotary percussive <span class="hlt">coring</span> <span class="hlt">drill</span>, forming a complete sampling instrument usable by robot or human. This method of in situ sample acquisition using micro - spine anchoring technology enables several NASA mission concepts not currently possible with existing technology, including sampling from consolidated rock on asteroids, providing a bolt network for astronauts visiting a near-Earth asteroid, and sampling from the ceilings or vertical walls of lava tubes and cliff faces on Mars. One of the most fundamental parameters of <span class="hlt">drilling</span> is the WOB; essentially, the load applied to the bit that allows it to cut, creating a reaction force normal to the surface. In every <span class="hlt">drilling</span> application, there is a minimum WOB that must be maintained for the system to function properly. In microgravity (asteroids and comets), even a small WOB could not be supported conventionally by the weight of the robot or astronaut. An anchoring mechanism would be needed to resist the reactions, or the robot or astronaut would push themselves off the surface and into space. The ability of the system to anchor itself to a surface creates potential applications that reach beyond use in low gravity. The use of these anchoring mechanisms as end effectors on climbing robots has the potential of vastly expanding the scope of what is considered accessible terrain. Further, because the <span class="hlt">drill</span> is supported by its own anchor rather than by a robotic arm, the workspace is not constrained by the reach of such an arm. Yet, if the <span class="hlt">drill</span> is on a robotic arm, it has the benefit of not reflecting the forces of <span class="hlt">drilling</span> back to the arm s joints. Combining the <span class="hlt">drill</span> with the anchoring feet will create a highly mobile, highly stable, and highly reliable system. The <span class="hlt">drilling</span> system s anchor uses hundreds of microspine toes that independently find holes and ledges on a rock to create an anchor. Once the system is anchored, a linear translation mechanism moves the <span class="hlt">drill</span> axially into the surface while maintaining the proper WOB. The linear translation mechanism is composed of a ball screw and stepper motor that can translate a carriage with high precision and applied load. The carriage slides along rails using self-aligning linear bearings that correct any axial misalignment caused by bending and torsion. The carriage then compresses a series of springs that simultaneously transmit the load to the <span class="hlt">drill</span> along the bit axis and act as a suspension that compensates for the vibration caused by percussive <span class="hlt">drilling</span>. The <span class="hlt">drill</span> is a compacted, modified version of an off-the-shelf rotary percussive <span class="hlt">drill</span>, which uses a custom carbide-tipped <span class="hlt">coring</span> bit. By using rotary percussive <span class="hlt">drilling</span>, the <span class="hlt">drill</span> time is greatly reduced. The percussive action fractures the rock debris, which is removed during rotation. The final result is a 0.75-in. (.1.9- cm) diameter hole and a preserved 0.5- in. (.1.3-cm) diameter rock <span class="hlt">core</span>. This work extends microspine technology, making it applicable to astronaut missions to asteroids and a host of robotic sampling concepts. At the time of this reporting, it is the first instrument to be demonstrated using microspine anchors, and is the first self-contained <span class="hlt">drill</span>/anchor system to be demonstrated that is capable of <span class="hlt">drilling</span> in inverted configurations and would be capable of <span class="hlt">drilling</span> in microgravity.</p> <div class="credits"> <p class="dwt_author">Parness, Aaron; Frost, Matthew A.; King, Jonathan P.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">308</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012AGUFM.V31D2823H"> <span id="translatedtitle">DEGAS experiments on volcanic glass samples from AND-1B <span class="hlt">drill</span> <span class="hlt">core</span>: implications for primary magmatic versus secondary H2O</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The existence of volcanic glass in the AND-1B <span class="hlt">drill</span> <span class="hlt">core</span> erupted subaquesously or even subglacially affords the possibility of constraining water depth by measuring the volatile content of the glass only if primary magmatic H2O contents can be recognized from secondary H2O. The glass samples studied come from Lithostratigraphic Unit (LU) 2 between 92 and 145 m depth. The black and well sorted sands from subunit 2.4 were most likely derived from subaerial Hawaiian/Strombolian type eruptions. The graded bedding exposed in this subunit may result from fallout of tephra through the water column. Glass fragments from six different depths within subunit 2.4 were extracted from AND-1B sediment first by magnetic separation and then approximately 100 mg of the freshest glass fragments were handpicked under a binocular microscope. The six glass separates were heated in a DEGAS-device up to 1450°C in high vacuum and the liberated volatiles were determined by a simultaneous mass spectrometric analysis. This study was focused on the determination of H2O, CO2, H2, HF, H2S, HCl, SO2, and hydrocarbon species. The six degassing experiments were carried out using a special high-vacuum-hot-extraction method combined with aquadrupol mass spectrometer. Measurements were carried out at less than 10-4 to 10-3Pa and a linear heating rate (10K/min) at a temperature range between room temperature to 1450°C. The volatile species were analyzed in multiple ion detection mode. DEGAS experiments occur under highly non-equilibrium conditions so that reverse reactions between volatiles or between volatiles and the melt are largely prevented. For each glass sample, volatile release occurs at different rates and intensities at different temperatures. Based on the gas release profiles obtained, degassing processes take place in three separate temperature ranges. Low temperature degassing occurs at temperatures up to 500°C and likely represents the liberation of surface bounded volatiles such as H2O in the samples from depths 110.87, 112.51 and 114.47. Moderate temperature degassing occurs between 500 and 800°C likely related to decomposition of silicate mineral (e.g. mica, illite) as well as sulfides with a maximum at 750°C. Above 700°C all samples release HF together with H2O, and HCl is liberated in two samples. A high temperature degassing process occurs above 1000°C and likely reflects the primary magmatic volatile content of the sample. Most characteristic of this degassing step is the SO2 release at a maximum of 1050°C and traces of HCl release. CO2 escaped over a large temperature interval of 600 to 1250°C. The DEGAS experiments consistently showed HCl, SO2 and H2S release above 1000°C. Moreover, secondary H2O predominates over primary magmatic H2O in the six ANDRILL glass samples. The low primary magmatic H2O contents suggest that the glasses were erupted subaerially and experienced near complete degassing during ascent and emplacement at the surface.</p> <div class="credits"> <p class="dwt_author">Heide, K.; Cameron, B. I.; Krans, S. R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">309</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..1510585U"> <span id="translatedtitle">The correlation of attenuated total reflectance infrared (ATR-FTIR) spectroscopic data with X-ray diffraction (XRD) parameters and its potential use for mineral identification and quantification in <span class="hlt">drilling</span> <span class="hlt">cores</span>: examples from the Pannonian Basin, Hungar</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Four thick sediment sequences in the following boreholes, Vízvár-I (0,0-2965,0 m) in the Dráva Basin, Som-I (999,5-1150,6 m) in southern Transdanubia, and two other boreholes, Doboz-I (3490-4434 m) and Doboz-III (2190-3400 m) in the Békés Basin, Hungary, were investigated in detail. Each <span class="hlt">drillings</span> cut across Neogene sequences and contain shales, carbonates and clay rocks (Tanács & Viczián, 1995). The selection of these <span class="hlt">cores</span> is due to the various amounts of smectite, illite and kaolinite minerals that are well manifested during comparison of infrared spectroscopic and former XRD dataset. During preparation, powdered <span class="hlt">core</span> samples were settled (</p> <div class="credits"> <p class="dwt_author">Udvardi, Beatrix; Kovács, István; Viczián, István; Hámor-Vidó, Mária; Mihály, Judith; Németh, Csaba</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">310</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012AGUFMOS31G..04F"> <span id="translatedtitle">Geological & <span class="hlt">Geophysical</span> findings from seismic, well log and <span class="hlt">core</span> data for marine gas hydrate deposits at the 1st offshore methane hydrate production test site in the eastern Nankai Trough, offshore Japan: An overview</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">In order to evaluate productivity of gas from marine gas hydrate by the depressurization method, Japan Oil, Gas and Metals National Corporation is planning to conduct a full-scale production test in early 2013 at the AT1 site in the north slope of Daini-Atsumi Knoll in the eastern Nankai Trough, Japan. The test location was determined using the combination of detailed 3D seismic reflection pattern analysis, high-density velocity analysis, and P-impedance inversion analysis, which were calibrated using well log data obtained in 2004. At the AT1 site, one production well (AT1-P) and two monitoring wells (AT1-MC and MT1) were <span class="hlt">drilled</span> from February to March 2012, followed by 1 <span class="hlt">coring</span> well (AT1-C) from June to July 2012. An extensive logging program with logging while <span class="hlt">drilling</span> (LWD) and wireline-logging tools, such as GeoVISION (resistivity image), EcoScope (neutron/density porosity, mineral spectroscopy etc.), SonicScanner (Advanced Sonic tool), CMR/ProVISION (Nuclear Magnetic Resonance Tools), XPT (formation pressure, fluid mobility), and IsolationScanner (ultrasonic cement evaluation tools) was conducted at AT1-MC well to evaluate physical reservoir properties of gas hydrate-bearing sediments, to determine production test interval in 2013, and to evaluate cement bonding. Methane hydrate concentrated zone (MHCZ) confirmed by the well logging at AT1-MC was thin turbidites (tens of centimeters to few meters) with 60 m of gross thickness, which is composed of lobe type sequences in the upper part of it and channel sand sequences in the lower part. The gross thickness of MHCZ in the well is thicker than previous wells in 2004 (A1, 45 m) located around 150 m northeast, indicating that the prediction given by seismic inversion analysis was reasonable. Well-to-well correlation between AT1-MC and MT1 wells within 40 m distance exhibited that lateral continuity of these sand layers (upper part of reservoir) are fairly good, which representing ideal reservoir for the production test. The XPT measurement results showed approximately 0.1 to several mD of water permeability in both the hydrate-bearing formation and seal formation, although there are some variations in measured values. However, the comparison of these results with permeability estimated by NMR log showed significant discrepancy (more than one order of difference), which suggests that it is necessary to have further investigation considering the difference in scale, measurement direction (Kh or Kv), and calibration methodology by pressure <span class="hlt">core</span> data. In order to obtain basic reservoir/seal properties for the well log calibration within and above production test interval, pressure <span class="hlt">coring</span> using Hybrid Pressure <span class="hlt">Coring</span> System (Hybrid PCS) and also non-destructive <span class="hlt">core</span> analysis onboard using Pressure <span class="hlt">Core</span> Analysis and Transfer System (PCATS) were conducted for 60 m interval in AT1-C, which located about 10 m northeast of AT1-MC. Finally, integrated reservoir characterization based on well-log and pressure <span class="hlt">core</span> data was conducted to predict and optimize the flow rate of upcoming production test.</p> <div class="credits"> <p class="dwt_author">Fujii, T.; Noguchi, S.; Takayama, T.; Suzuki, K.; Yamamoto, K.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">311</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=ADA192196"> <span id="translatedtitle"><span class="hlt">Drill</span> Instructor.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">This project was designed to develop a stress coping program for <span class="hlt">drill</span> instructors. The program consists of (1) 6 videotaped modules on key times concerning stress and coping, (2) 8 vignettes on recurrent problem situations and how to handle them, and (3)...</p> <div class="credits"> <p class="dwt_author">I. G. Sarason</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">312</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/823392"> <span id="translatedtitle">RESULTS FROM THE (1) DATA COLLECTION WORKSHOP, (2) MODELING WORKSHOP AND (3) <span class="hlt">DRILLING</span> AND <span class="hlt">CORING</span> METHODS WORKSHOP AS PART OF THE JOINT INDUSTRY PARTICIPATION (JIP) PROJECT TO CHARACTERIZE NATURAL GAS HYDRATES IN THE DEEPWATER GULF OF MEXICO</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">In 2000, Chevron began a project to learn how to characterize the natural gas hydrate deposits in the deepwater portions of the Gulf of Mexico. A Joint Industry Participation (JIP) group was formed in 2001, and a project partially funded by the U.S. Department of Energy (DOE) began in October 2001. The primary objective of this project is to develop technology and data to assist in the characterization of naturally occurring gas hydrates in the deepwater Gulf of Mexico. These naturally occurring gas hydrates can cause problems relating to <span class="hlt">drilling</span> and production of oil and gas, as well as building and operating pipelines. Other objectives of this project are to better understand how natural gas hydrates can affect seafloor stability, to gather data that can be used to study climate change, and to determine how the results of this project can be used to assess if and how gas hydrates act as a trapping mechanism for shallow oil or gas reservoirs. As part of the project, three workshops were held. The first was a data collection workshop, held in Houston during March 14-15, 2002. The purpose of this workshop was to find out what data exist on gas hydrates and to begin making that data available to the JIP. The second and third workshop, on Geoscience and Reservoir Modeling, and <span class="hlt">Drilling</span> and <span class="hlt">Coring</span> Methods, respectively, were held simultaneously in Houston during May 9-10, 2002. The Modeling Workshop was conducted to find out what data the various engineers, scientists and geoscientists want the JIP to collect in both the field and the laboratory. The <span class="hlt">Drilling</span> and <span class="hlt">Coring</span> workshop was to begin making plans on how we can collect the data required by the project's principal investigators.</p> <div class="credits"> <p class="dwt_author">Stephen A. Holditch; Emrys Jones</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-09-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">313</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006JGRD..111.3304P"> <span id="translatedtitle">Atmospheric methane sulfonate and non-sea-salt sulfate records at the European Project for Ice <span class="hlt">Coring</span> in Antarctica (EPICA) deep-<span class="hlt">drilling</span> site in Dronning Maud Land, Antarctica</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">During three summer campaigns in January/February 2000, 2001, and 2002 the ionic composition of the aerosol at the European Project for Ice <span class="hlt">Coring</span> in Antarctica (EPICA) deep-<span class="hlt">drilling</span> site at Kohnen Station was measured in daily resolution. In 2000 and 2002 we observed mean (±std) non-sea-salt sulfate (nss-SO42-) concentrations of 353 ± 100 ng m-3 and 320 ± 250 ng m-3, as well as methane sulfonate (MS) concentrations of 59 ± 36 ng m-3 and 74 ± 80 ng m-3, respectively. For the summer campaign in 2001, significantly lower nss-SO42- and MS levels of 164 ± 150 ng m-3 and 19 ± 12 ng m-3, respectively, were typical. The mean MS/nss-SO42- ratio ranged from about 0.1 to 0.2. MS and nss-SO42- concentrations and their variability were roughly comparable to coastal stations at summer. Supported by air mass back trajectory analyses, this finding documented an efficient long-range transport to Kohnen via the free troposphere. MS/nss-SO42- ratios exhibited a strong dependence on the MS concentration with systematically higher ratios at higher MS concentrations, a peculiarity which is also evident in a firn <span class="hlt">core</span> <span class="hlt">drilled</span> at this site.</p> <div class="credits"> <p class="dwt_author">Piel, C.; Weller, R.; Huke, M.; Wagenbach, D.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-02-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">314</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFM.P42B..04B"> <span id="translatedtitle"><span class="hlt">Geophysical</span> Monitoring Station (GEMS)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">GEMS (<span class="hlt">GEophysical</span> Monitoring Station) is one of three missions undergoing Phase A development for possible selection by NASA's Discovery Program. If selected, GEMS will perform the first comprehensive surface-based <span class="hlt">geophysical</span> investigation of Mars, filling a longstanding gap in the scientific exploration of the solar system. It will illuminate the fundamental processes of terrestrial planet formation and evolution, providing unique and critical information about the initial accretion of the planet, the formation and differentiation of the <span class="hlt">core</span> and crust, and the subsequent evolution of the interior. The scientific goals of GEMS are to understand the formation and evolution of terrestrial planets through investigation of the interior structure and processes of Mars and to determine its present level of tectonic activity and impact flux. A straightforward set of scientific objectives address these goals: 1) Determine the size, composition and physical state of the <span class="hlt">core</span>; 2) Determine the thickness and structure of the crust; 3) Determine the composition and structure of the mantle; 4) Determine the thermal state of the interior; 5) Measure the rate and distribution of internal seismic activity; and 6) Measure the rate of impacts on the surface. To accomplish these objectives, GEMS carries a tightly-focused payload consisting of 3 investigations: 1) SEIS, a 6-component, very-broad-band seismometer, with careful thermal compensation/control and a sensitivity comparable to the best terrestrial instruments across a frequency range of 1 mHz to 50 Hz; 2) HP3 (Heat Flow and Physical Properties Package), an instrumented self-penetrating mole system that trails a string of temperature sensors to measure the thermal gradient and conductivity of the upper several meters, and thus the planetary heat flux; and 3) RISE (Rotation and Interior Structure Experiment), which would use the spacecraft X-band communication system to provide precision tracking for planetary dynamical studies. The two instruments are moved from the lander deck to the martian surface by an Instrument Deployment Arm, with an appropriate location identified using an Instrument Deployment Camera. In order to ensure low risk within the tight Discovery cost limits, GEMS reuses the successful Lockheed Martin Phoenix spacecraft design, with a cruise and EDL system that has demonstrated capability for safe landing on Mars with well-understood costs. To take full advantage of this approach, all science requirements (such as instrument mass and power, landing site, and downlinked data volume) strictly conform to existing, demonstrated capabilities of the spacecraft and mission system. It is widely believed that multiple landers making simultaneous measurements (a network) are required to address the objectives for understanding terrestrial planet interiors. Nonetheless, comprehensive measurements from a single <span class="hlt">geophysical</span> station are extremely valuable, because observations constraining the structure and processes of the deep interior of Mars are virtually nonexistent. GEMS would utilize sophisticated analysis techniques specific to single-station measurements to determine crustal thickness, mantle structure, <span class="hlt">core</span> state and size, and heat flow, providing our first real look deep beneath the surface of Mars.</p> <div class="credits"> <p class="dwt_author">Banerdt, B.; Dehant, V. M.; Lognonne, P.; Smrekar, S. E.; Spohn, T.; GEMS Mission Team</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">315</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6209467"> <span id="translatedtitle"><span class="hlt">Drills</span> for mining applications</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary"><span class="hlt">Drills</span> are the most universal mining tools, with applications both above and below ground in exploration, blasting, and a sampling. The criteria considered in the design of <span class="hlt">drills</span> is economical energy usage, simple handling, and extensive use of mechanization and automation. The operation and performance of <span class="hlt">drills</span> in down-hole <span class="hlt">drilling</span>, underground <span class="hlt">drilling</span>, and exploration are discussed. <span class="hlt">Drill</span> accessories are also discussed.</p> <div class="credits"> <p class="dwt_author">Not Available</p> <p class="dwt_publisher"></p> <p class="publishDate">1984-02-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">316</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/55408525"> <span id="translatedtitle">Exploring Arctic history through scientific <span class="hlt">drilling</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">During the brief Arctic summer of 1993, the Ocean <span class="hlt">Drilling</span> Program's research vessel JOIDES Resolution recovered the first scientific <span class="hlt">drill</span> <span class="hlt">cores</span> from the eastern Arctic Ocean. Dodging rafts of pack ice shed from the Arctic ice cap, the science party sampled sediments north of 80°N latitude from the Yermak Plateau, as well as from sites in Fram Strait, the northeastern</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">1994-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">317</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/60693"> <span id="translatedtitle">Petrography and phenocryst chemistry of volcanic units at Yucca Mountain, Nevada: A comparison of outcrop and <span class="hlt">drill</span> hole samples</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">This report is a compilation of petrographic and mineral chemical data for stratigraphic units at Yucca Mountain. It supports a possible peer review of Yucca Mountain <span class="hlt">drill</span> <span class="hlt">core</span> by summarizing the available data in a form that allows comparison of stratigraphic units in <span class="hlt">drill</span> holes with surface outcrops of the same units. Petrographic and mineral chemical data can be used in conjunction with other geologic and <span class="hlt">geophysical</span> information to determine if stratigraphic relations in Yucca Mountain <span class="hlt">drill</span> <span class="hlt">core</span> are geologically reasonable and compare well with relations known from extensive surface studies. This compilation of petrographic and mineral chemical data is complete enough for most stratigraphic units to be used in a peer review of Yucca Mountain <span class="hlt">drill</span> <span class="hlt">core</span>. Additional data must be collected for a few units to complete the characterization. Rock units at Yucca Mountain have unique petrographic and mineral chemical characteristics that can be used to make accurate stratigraphic assignments in <span class="hlt">drill</span> <span class="hlt">core</span> samples. Stratigraphic units can be differentiated on the basis of petrographic characteristics such as total phenocryst abundances, relative proportions of phenocryst minerals, and type and abundances of mafic and accessory minerals. The mineral chemistry of phenocrysts is also an important means of differentiating among stratigraphic units, especially when used in conjunction with the petrographic data. Sanidine phenocrysts and plagioclase rims have narrow compositional ranges for most units and often have well-defined dominant compositions. Biotite compositions are useful for identifying groups of related units (e.g., Paintbrush Tuff Members vs Crater Flat Tuff Members) and for providing an important check on the consistency of the data. 21 refs., 12 figs., 2 tabs.</p> <div class="credits"> <p class="dwt_author">Broxton, D.E.; Byers, F.M. Jr.; Warren, R.G.</p> <p class="dwt_publisher"></p> <p class="publishDate">1989-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">318</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.usgs.gov/of/2006/1213/@displayLabelzip@noteADDITIONAL+REPORT+PIECE#texthttp://pubs.usgs.gov/of/2006/1213/app7.zip"> <span id="translatedtitle">Analytical results from samples collected during coal-bed methane exploration <span class="hlt">drilling</span> in Caldwell Parish, Louisiana</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">In 2001, and 2002, the U.S. Geological Survey (USGS) and the Louisiana Geological Survey (LGS), through a Cooperative Research and Development Agreement (CRADA) with Devon SFS Operating, Inc. (Devon), participated in an exploratory <span class="hlt">drilling</span> and <span class="hlt">coring</span> program for coal-bed methane in north-central Louisiana. The USGS and LGS collected 25 coal <span class="hlt">core</span> and cuttings samples from two coal-bed methane test wells that were <span class="hlt">drilled</span> in west-central Caldwell Parish, Louisiana. The purpose of this report is to provide the results of the analytical program conducted on the USGS/LGS samples. The data generated from this project are summarized in various topical sections that include: 1. molecular and isotopic data from coal gas samples; 2. results of low-temperature ashing and X-ray analysis; 3. palynological data; 4. down-hole temperature data; 5. detailed <span class="hlt">core</span> descriptions and selected <span class="hlt">core</span> photographs; 6. coal physical and chemical analytical data; 7. coal gas desorption results; 8. methane and carbon dioxide coal sorption data; 9. coal petrographic results; and 10. <span class="hlt">geophysical</span> logs.</p> <div class="credits"> <p class="dwt_author">Warwick, Peter D.; Breland, F. Clayton, Jr.; Hackley, Paul C.; Dulong, Frank T.; Nichols, Douglas J.; Karlsen, Alexander W.; Bustin, R. Marc; Barker, Charles E.; Willett, Jason C.; Trippi, Michael H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">319</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013AGUFMGP43A1178H"> <span id="translatedtitle">Response of magnetic susceptibility in Quaternary lacustrine sediments of the Qaidam Basin (NE Tibetan Plateau) to orbital forcing: applying time series analyses to improve magnetostratigraphic dating of <span class="hlt">drill</span> <span class="hlt">core</span> SG-1</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Cenozoic lacustrine sediments around the <span class="hlt">drilling</span> site of the ~940-m-long <span class="hlt">core</span> SG-1 from the western Qaidam Basin (NE Tibetan Plateau) in the Chahansilatu sub-depression, having a thickness of up to 6,000 m, offer a great archive for studying past climate change. Magnetostratigraphic dating of SG-1 reveals an average sediment accumulation rate of 35 cm/kyr and a time span ranging from ~2.8 to ~0.1 Ma. Beside several non-magnetic proxies, mass-specific magnetic susceptibility (?) shows a response to past environmental change. The ? time series displays high-amplitude cyclicities (beside long-term trends), which can be attributed to orbital forcing. Major Milankovitch cycles can be detected as well as the occurrence of spectral power near periods corresponding to nonlinear responses to orbital forcing (near the typical periods of ~30, ~54, and ~70 ka). The Middle Pleistocene Transition (MPT; ~1.2-0.7 Ma) can also be observed in the ? record of SG-1, represented by a typical shift of main spectral power in the 41-kyr obliquity to an additional appearance of the 100-kyr eccentricity band. We attempt to use this climate forced signals of the ? record to establish a more detailed depth-to-time transformation for <span class="hlt">drill</span> <span class="hlt">core</span> SG-1 based on cyclostratigraphy and spectral analysis of ? in windows, with the magnetic polarity boundaries as tie points. Due to the changing spectral power of the Milankovitch cycles along the <span class="hlt">core</span>, SG-1 has to be divided into different parts with different prominences of the 41- and 100-ka cycle, as well as cycles originating from nonlinear climate responses.</p> <div class="credits"> <p class="dwt_author">Herb, C.; Appel, E.; Voigt, S.; Zhang, W.; Fang, X.; Koutsodendris, A.; Pross, J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">320</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/53195068"> <span id="translatedtitle">Oceanic <span class="hlt">Core</span> Complexes and Crustal Accretion at Slow-Spreading Ridges. Indications From IODP Expeditions 304-305 and Previous Ocean <span class="hlt">Drilling</span> Results</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Oceanic <span class="hlt">core</span> complexes expose intrusive crustal rocks on the seafloor via detachment faulting and are often associated with significant extents of serpentinized mantle peridotite at the seafloor. These serpentinite units have unknown thickness in most cases. Assuming that steep slopes surrounding the domal <span class="hlt">core</span> provide a cross section, one would infer they comprise much of the section for depths of</p> <div class="credits"> <p class="dwt_author">B. Ildefonse; D. K. Blackman; B. E. John; Y. Ohara; D. J. Miller; C. J. MacLeod</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_15");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' 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showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a style="font-weight: bold;">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_18");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">321</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://nicl.usgs.gov/index.html"> <span id="translatedtitle">USGS National Ice <span class="hlt">Core</span> Laboratory</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This United States Geological Survey site highlights the work of the National Ice <span class="hlt">Core</span> Laboratory (NICL). It discusses the NICL's role, why ice <span class="hlt">cores</span> are important to study, how ice <span class="hlt">cores</span> are <span class="hlt">drilled</span> and studied, and <span class="hlt">core</span> <span class="hlt">drilling</span> locations. These <span class="hlt">cores</span> are recovered and studied for a variety of scientific investigations, most of which focus on the reconstruction of Earth's climate history. The facility currently houses over 14,000 meters of ice <span class="hlt">cores</span> from 34 <span class="hlt">drill</span> sites in Greenland, Antarctica, and high mountain glaciers in the Western United States. There are links for more information and individual <span class="hlt">core</span> information such as numbers, locations and sizes.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">322</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/484551"> <span id="translatedtitle">Basalt features observed in outcrops, <span class="hlt">cores</span>, borehole video imagery and <span class="hlt">geophysical</span> logs, and basalt hydrogeologic study at the Idaho National Engineering Laboratory, Eastern Idaho</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">A study was undertaken to examine permeable zones identified in boreholes open to the underlying basalt and to describe the vertical cross flows present in the boreholes. To understand the permeable zones in the boreholes detailed descriptions and measurements of three outcrops in the Snake River Plain, three <span class="hlt">cores</span> at the Idaho Chemical Processing Plant (ICPP) at the INEL, and over fifty borehole TV logs from the INEL were carried out. Based on the observations made on the three outcrops an idealized basalt lava flow model was generated that used a set of nomenclature that would be standard for the basalt lava flows studied. An upper vesicular zone, a sometimes absent columnar zone, central zone, and lower vesicular zone make up the basalt lava flow model. The overall distinction between the different zones are based on the vesicle shape size, vesicularity, and fractures present. The results of the studies also indicated that the basalt lava flows at the INEL are distal to medial facies pahoehoe lava flows with close fitting contacts. The most permeable zones identified in these basalts are fractured vesiculated portions of the top of the lava flow, the columnar areas, and basalt-flow contacts in order of importance. This was determined from impeller flowmeter logging at the INEL. Having this information a detailed stratigraphy of individual basalt lava flows and the corresponding permeable units were generated. From this it was concluded that groundwater flow at the ICPP prefers to travel along thin basalt lava flows or flow-units. Flow direction and velocity of intrawell flows detected by flowmeter is controlled by a nearby pumping well.</p> <div class="credits"> <p class="dwt_author">Bennecke, W.M.</p> <p class="dwt_publisher"></p> <p class="publishDate">1996-10-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">323</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/doepatents/biblio/867746"> <span id="translatedtitle">Fiber optic <span class="hlt">geophysical</span> sensors</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p class="result-summary">A fiber optic <span class="hlt">geophysical</span> sensor in which laser light is passed through a sensor interferometer in contact with a <span class="hlt">geophysical</span> event, and a reference interferometer not in contact with the <span class="hlt">geophysical</span> event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects.</p> <div class="credits"> <p class="dwt_author">Homuth, Emil F. (Los Alamos, NM)</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">324</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60558231"> <span id="translatedtitle">Environmental <span class="hlt">geophysics</span> at Beach Point, Aberdeen Proving Ground, Maryland</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary"><span class="hlt">Geophysical</span> studies at Beach Point Peninsula, in the Edgewood area of Aberdeen Proving Ground, Maryland, provide diagnostic signatures of the hydrogeologic framework and possible contaminant pathways. These studies permit construction of the most reasonable scenario linking dense, nonaqueous-phase liquid contaminants introduced at the surface with their pathway through the surficial aquifer. Subsurface geology and contaminant presence were identified by <span class="hlt">drilling</span>,</p> <div class="credits"> <p class="dwt_author">L. D. McGinnis; C. R. Daudt; M. D. Thompson; S. F. Miller; W. A. Mandell; J. Wrobel</p> <p class="dwt_publisher"></p> <p class="publishDate">1994-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">325</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1985EOSTr..66U...1."> <span id="translatedtitle">Professorship of <span class="hlt">Geophysics</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Columbia University has established a new professorship of <span class="hlt">geophysics</span> in its School of Engineering and Applied Science. The Maurice Ewing and J. Lamar Worzel Professorship of <span class="hlt">Geophysics</span> has been established with an endowment of $1 million. Palisades <span class="hlt">Geophysical</span> Institute, Inc., a nonprofit research group based in West Nyack, N.Y., provided a gift of $500,000.The late Maurice Ewing, who died in 1974, was the founder of Columbia's Lamont-Doherty Geological Observatory. J. Lamar Worzel, a long-time colleague of Ewing, is now president of the Palisades <span class="hlt">Geophysical</span> Institute.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">326</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=METCCR801"> <span id="translatedtitle">Chattanooga Shale (Devonian and Mississippian) from the Tennessee Division of Geology - US Department of Energy <span class="hlt">Cored</span> <span class="hlt">Drill</span> Holes Number 1 and 2, Claiborne County, Tennessee.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">The Chattanooga Shale of the Newman Ridge syncline lies stratigraphically above the Silurian Hancock Dolomite and below the siltstone and shale of the Mississippian Grainger Formation. <span class="hlt">Core</span> examination indicates that the Chattanooga is predominately a bla...</p> <div class="credits"> <p class="dwt_author">J. B. Roen R. C. Milici R. C. Kepferle L. G. Wallace</p> <p class="dwt_publisher"></p> <p class="publishDate">1980-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">327</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1985utia.rept.....S"> <span id="translatedtitle">Uranium, thorium isotopic analyses and uranium-series ages of calcite and opal and stable isotopic compositions of calcite from <span class="hlt">drill</span> <span class="hlt">cores</span> UE25a no. 1, USR G-2 and USW G-3/GU-3, Yucca Mountain, Nevada</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Fracture and cavity filling calcite and opal in the unsaturated zone of three <span class="hlt">drill</span> <span class="hlt">cores</span> at Yucca Mountain were analyzed for uranium and stable isotope contents, and were dated by the uranium-series method. Stable isotope data indicate that the water from which the calcite precipitated was meteoric in origin. The decrease in O-18 and increase in C-13 with depth are interpreted as being due to the increase in temperature in <span class="hlt">drill</span> holes corresponding to an estimated maximum geothermal gradient of 43 deg per km. Of the eighteen calcite and opal deposits dated, four of the calcite and all four of the opal deposits yield dates older than 400,000 years and ten of the remaining calcite deposits yield dates between 26,000 and 310,000 years. The stable isotope and uranium data together with the finite uranium-series dates of precipitation suggest a complex history of fluid movements, rock and water interactions, and episodes of fracture filling during the last 310,000 years.</p> <div class="credits"> <p class="dwt_author">Szabo, B. J.; Kyser, T. K.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">328</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/138760"> <span id="translatedtitle">Assessment of <span class="hlt">geophysical</span> logs from borehole USW G-2, Yucca Mountain, Nevada</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Commercial logging contractors, Western Atlas, Schlumberger, and Edcon obtained borehole <span class="hlt">geophysical</span> logs at the site of a potential high level nuclear waste repository at Yucca Mountain, Nevada. <span class="hlt">Drill</span> hole USW-G2 was picked for this test of suitable logging tools and logging technology, both representing state-of-the-art technology by these commercial companies. Experience gained by analysis of existing <span class="hlt">core</span> data and a variety of logs obtained earlier by Birdwell and Dresser Atlas served as a guide to a choice of logs to be obtained. Logs were obtained in water-filled borehole in zeolitized tuff (saturated zone) and in air-filled borehole largely in unaltered welded tuff (unsaturated zone).</p> <div class="credits"> <p class="dwt_author">Nelson, P.H. [Geological Survey, Denver, CO (United States); Schimschal, U. [Bureau of Reclamation, Denver, CO (United States)</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-05-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">329</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19940007608&hterms=Blum&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DBlum"> <span id="translatedtitle">Strontium and oxygen isotope study of M-1, M-3 and M-4 <span class="hlt">drill</span> <span class="hlt">core</span> samples from the Manson impact structure, Iowa: Comparison with Haitian K-T impact glasses</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p class="result-summary">Strontium and oxygen isotope analyses were performed on 8 samples from the M-1, M-3, and M-4 <span class="hlt">cores</span> recently <span class="hlt">drilled</span> at the Manson impact structure. The samples were three elastic sedimentary rocks (of probable Cretaceous age) which occurred as clasts within the sedimentary clast breccia, two samples of crystalline rock breccia matrix, and three samples of dolomite and limestone. The Sr-87/Sr-86 (corrected to 65 Ma) ratios were much higher than those in impact glasses from the Haitian Cretaceous-Tertiary (K-T) boundary. Isotope mixing calculations demonstrate that neither the silicate or carbonate rocks analyzed from the Manson crater, or mixtures of these rocks are appropriate source materials for the Haitian impact glasses. However, the Sr-87/Sr-86 (65Ma) ratio and delta O-18 value of the Ca-rich Haitian glasses are well reproduced by mixtures of Si-rich Haitian glass with platform carbonate of K-T age.</p> <div class="credits"> <p class="dwt_author">Blum, Joel D.; Chamberlain, C. Page; Hingston, Michael P.; Koeberl, Christian</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">330</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.er.usgs.gov/publication/ofr20141057"> <span id="translatedtitle">Histograms showing variations in oil yield, water yield, and specific gravity of oil from Fischer assay analyses of oil-shale <span class="hlt">drill</span> <span class="hlt">cores</span> and cuttings from the Piceance Basin, northwestern Colorado</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">Recent studies indicate that the Piceance Basin in northwestern Colorado contains over 1.5 trillion barrels of oil in place, making the basin the largest known oil-shale deposit in the world. Previously published histograms display oil-yield variations with depth and widely correlate rich and lean oil-shale beds and zones throughout the basin. Histograms in this report display oil-yield data plotted alongside either water-yield or oil specific-gravity data. Fischer assay analyses of <span class="hlt">core</span> and cutting samples collected from exploration <span class="hlt">drill</span> holes penetrating the Eocene Green River Formation in the Piceance Basin can aid in determining the origins of those deposits, as well as estimating the amount of organic matter, halite, nahcolite, and water-bearing minerals. This report focuses only on the oil yield plotted against water yield and oil specific gravity.</p> <div class="credits"> <p class="dwt_author">Dietrich, John D.; Brownfield, Michael E.; Johnson, Ronald C.; Mercier, Tracey J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2014-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">331</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ri.cmu.edu/pub_files/pub3/labelle_diana_2001_1/labelle_diana_2001_1.pdf"> <span id="translatedtitle">Lithological Classification by <span class="hlt">Drilling</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">There are many <span class="hlt">drilling</span> tasks in which <span class="hlt">drill</span> monitoring is used to improve the quality of a product: detecting tool breakage in manufacturing <span class="hlt">drilling</span>, exploratory <span class="hlt">drilling</span> for oil and natural gas reservoirs, collecting soil samples on Mars with a robotic <span class="hlt">drill</span>. However, in many applications, a human is partially or entirely responsible for controlling and analyzing the interaction between the</p> <div class="credits"> <p class="dwt_author">Diana LaBelle</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">332</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://files.eric.ed.gov/fulltext/ED013042.pdf"> <span id="translatedtitle">WRITING ORAL <span class="hlt">DRILLS</span>.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p class="result-summary">ALL ORAL LANGUAGE <span class="hlt">DRILLS</span> MAY BE SEPARATED INTO TWO TYPES--(1) MIM-MEM OR MIMICRY MEMORIZATION <span class="hlt">DRILLS</span> OR (2) PATTERN PRACTICE <span class="hlt">DRILLS</span>. THESE TWO LARGER CATEGORIES CAN BE SUB-DIVIDED INTO A NUMBER OF OTHER TYPES, SUCH AS TRANSFORMATION AND SUBSTITUTION <span class="hlt">DRILLS</span>. THE USE OF ANY PARTICULAR TYPE DEPENDS ON THE PURPOSE TO WHICH THE <span class="hlt">DRILL</span> IS PUT. IN ANY…</p> <div class="credits"> <p class="dwt_author">NEY, JAMES W.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">333</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..1512007D"> <span id="translatedtitle">Rationale for future Antarctic and Southern Ocean <span class="hlt">drilling</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Valuable insights into future sensitivity of the Antarctic cryosphere to atmospheric and oceanic warming can be gained from the geologic record of past climatic warm intervals. Continental to deep ocean sediments provide records of contemporaneous changes in ice sheet extent and oceanographic conditions that extend back in time, including periods with atmospheric CO2 levels and temperatures similar to those likely to be reached in the next 100 years. The Circum-Antarctic region is under-sampled respect to scientific ocean <span class="hlt">drilling</span>. However, recovery from glacially-influenced, continental shelf and rise sediments (expeditions ODP178, 188 and IODP 318), provided excellent records of Cenozoic climate and ice sheet evolution. The ANtarctic <span class="hlt">DRILLing</span> program achieved >98% recovery on the Ross Sea shelf with a stable platform on fast ice with riser <span class="hlt">drilling</span> technology. Newer technologies, such as the MeBo shallow <span class="hlt">drilling</span> rig will further improve Antarctic margin <span class="hlt">drilling</span>. <span class="hlt">Drilling</span> around Antarctica in the past decades revealed cooling and regional ice growth during the Cenozoic, coupled with paleogeographic, CO2 atmosphere concentration and global temperature changes. Substantial progress has been made in dating sediments and in the interpretation of paleoclimate/paleoenvironmental proxies in Antarctic margin sediments (e.g. orbital scale variations in Antarctica's cryosphere during the Miocene and Pliocene). Holocene ultra-high resolution shelf sections recently recovered can be correlated to the ice <span class="hlt">core</span> record, to detect local mechanisms versus inter-hemispheric connections. While the potential for reconstructing past ice sheet history has been demonstrated through a careful integration of geological and <span class="hlt">geophysical</span> data with numerical ice sheet modelling, uncertainties remain high due to the sparse geographic distribution of the records and the regional variability in the ice sheet's response. Projects developed using a multi-leg, multi-platform approach (e.g. latitudinal and/or depth transects involving a combination of land/ice shelf, seabed, riser, and riserless <span class="hlt">drilling</span> platforms) will likely make the most significant scientific advances. Fundamental hypothesis can be tested and accomplished by <span class="hlt">drilling</span> depth transects from ice-proximal to ice-distal locations, that will enable researchers to link past perturbations in the ice sheet with Southern Ocean and global climate dynamics. The variable response of the ice sheet to ongoing climatic change mandates broad geographic <span class="hlt">drilling</span> coverage, particularly in climatically sensitive regions, like those with large upstream drainage basins, whose marine terminus is presently melting, due to ocean, warming water impinging the continental shelf. Key transects were identified at community workshops (http://www.scar-ace.org) in the frame of the SCAR/ACE (Antarctic Climate Evolution) and PAIS (Past Antarctic Ice Sheet dynamics) programs. New proposals, also for MSP expeditions were then submitted to IODP, in addition to the existing ones, in the frame of a scientific concerted strategy and with a significant European participation. Main questions underpinning future scientific <span class="hlt">drilling</span> tied IODP Science themes: 1) How did and will the Antarctic Ice Sheets respond to elevated temperatures and atmospheric pCO2? What is the contribution of Antarctic ice to past and future sea level changes? 2) What was the timing of rifting and subsidence controlling the opening of ocean gateways and the initiation of the circumpolar current system and the onset of glaciations?</p> <div class="credits"> <p class="dwt_author">De Santis, Laura; Gohl, Karsten; Larter, Rob; Escutia, Carlota; Ikehara, Minoru; Hong, JongKuk; Naish, Tim; Barrett, Peter; Rack, Frank; Wellner, Julia</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">334</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/61395910"> <span id="translatedtitle">Lithology and stratigraphy of selected <span class="hlt">drill</span> holes in LANL use areas of Yucca Flat, Nevada Test Site. Volume V</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">This report is a compilation of data from <span class="hlt">drill</span> holes completed, except where noted, during the calendar year 1983 in areas used by Los Alamos National Laboratory in Yucca Flat, Nevada Test Site. Data presented in this report includes hole locations, <span class="hlt">drilling</span> statistics, a supplemental data sheet, stratigraphy and lithology penetrated, and selected <span class="hlt">geophysical</span> logs including a log of <span class="hlt">drilling</span></p> <div class="credits"> <p class="dwt_author">S. L. Jr. Drellack; J. L. Gonzales; W. J. Davies</p> <p class="dwt_publisher"></p> <p class="publishDate">1984-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">335</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48558700"> <span id="translatedtitle"><span class="hlt">Geophysics</span> For Slope Stability</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">A pre-requisite in slope stability analyses is that the internal structure and the mechanical properties of the soil or rock mass of the slope, are known or can be estimated with a reasonable degree of certainty. <span class="hlt">Geophysical</span> methods to determine the internal structure of a soil or rock mass may be used for this purpose. Various <span class="hlt">geophysical</span> methods and their</p> <div class="credits"> <p class="dwt_author">Robert Hack</p> <p class="dwt_publisher"></p> <p class="publishDate">2000-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">336</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://dx.doi.org/10.1016/S0012-821X(00)00077-7"> <span id="translatedtitle">Anisotropy of magnetic susceptibility as a tool for recognizing <span class="hlt">core</span> deformation: reevaluation of the paleomagnetic record of Pleistocene sediments from <span class="hlt">drill</span> hole OL-92, Owens Lake, California</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">At Owens Lake, California, paleomagnetic data document the Matuyama/Brunhes polarity boundary near the bottom of a 323-m <span class="hlt">core</span> (OL-92) and display numerous directional fluctuations throughout the Brunhes chron. Many of the intervals of high directional dispersion were previously interpreted to record magnetic excursions. For the upper ~120 m, these interpretations were tested using the anisotropy of magnetic susceptibility (AMS), which typically defines a subhorizontal planar fabric for sediments deposited in quiet water. AMS data from intervals of deformed <span class="hlt">core</span>, determined from detailed analysis of sedimentary structures, were compared to a reference AMS fabric derived from undisturbed sediment. This comparison shows that changes in the AMS fabric provide a means of screening <span class="hlt">core</span> samples for deformation and the associated paleomagnetic record for the adverse effects of distortion. For that portion of <span class="hlt">core</span> OL-92 studied here (about the upper 120 m), the combined analyses of sedimentary structures and AMS data demonstrate that most of the paleomagnetic features, previously interpreted as geomagnetic excursions, are likely the result of <span class="hlt">core</span> deformation.</p> <div class="credits"> <p class="dwt_author">Rosenbaum, Joseph; Reynolds, Richard; Smoot, Joseph; Meyer, Robert</p> <p class="dwt_publisher"></p> <p class="publishDate">2000-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">337</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/17974213"> <span id="translatedtitle">[The new eubacterium Roseomonas baikalica sp. nov. isolated from <span class="hlt">core</span> samples collected by deep-hole <span class="hlt">drilling</span> of the bottom of Lake Ba?kal].</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Microbiological analysis of samples of sedimentary rocks from various eras of the geological history of the Baikal rift has enabled us to isolate a large number of microorganisms that can be classified into new, previously undescribed species. The present work deals with the identification and study of the morphological, biochemical, and physiological properties of one such strain, Che 82, isolated from sample C-29 of 3.4-3.5 Ma-old sedimentary rocks taken at a <span class="hlt">drilling</span> depth of 146.74 m. As a result of our investigations, strain Che 82 is described as a new bacterial species, Roseomonas baikalica sp. nov., belonging to the genus Roseomonas within the family Methylobacteriaceae, class Alphaproteobacteria. PMID:17974213</p> <div class="credits"> <p class="dwt_author">Andreeva, I S; Pechurkina, N I; Morozova, O V; Riabchikova, E I; Belikov, S I; Puchkova, L I; Emel'ianova, E K; Torok, T; Repin, V E</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">338</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/263928"> <span id="translatedtitle">Probability of ignition of reactive wastes by rotary sampling <span class="hlt">drills</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Sampling with a rotary <span class="hlt">drill</span> could potentially cause a fire in some Hanford tanks. If the rotary <span class="hlt">drill</span> experiences a failure while in fuel-rich, dry waste, the waste could be ignited by the hot <span class="hlt">drill</span> bit. For the saltcake tanks subject to this hazard, this report presents a methodology for calculating the probabilities of fire due to <span class="hlt">core</span> <span class="hlt">drill</span> failure. The methodology utilizes sampling data from tank characterization studies to determine the amount of reactive waste in the tanks.</p> <div class="credits"> <p class="dwt_author">Heasler, P.G.</p> <p class="dwt_publisher"></p> <p class="publishDate">1996-06-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">339</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012AGUFM.T13F2692E"> <span id="translatedtitle">The Japan Trench Fast <span class="hlt">Drilling</span> Project (IODP Exp. 343&343T JFAST): Making Scientific <span class="hlt">Drilling</span> History in the Japan Trench</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The international scientific community began planning the Japan Trench Fast <span class="hlt">Drilling</span> Project (JFAST) soon after the 11 March Tohoku Earthquake occurred. Predicted rapid decay of any thermal anomaly resulting from shear heating, which may allow the frictional strength of the main slip zone to be calculated, dictated that temperature measurements needed to be made within 18 months of the initial earthquake. Based on the <span class="hlt">drilling</span> and observatory request from the science team, the Center for Deep Earth Exploration (CDEX) began scoping activities for this project, and rapidly became aware of some of the daunting technical challenges involved in <span class="hlt">drilling</span> in approximately 7 km of water. The deepest water depth <span class="hlt">drilling</span> in scientific ocean <span class="hlt">drilling</span> history was in the Marianas Trench in 1978 in water depth of 7,049.5 m with 15.5 m penetration. The original plan of JFAST required logging-while-<span class="hlt">drilling</span> (LWD) and sample collection from 1,000 m below the seafloor in 7,000 m water depth in the Japan Trench. Beyond this, temperature observatories needed to be deployed into the borehole. A scientific <span class="hlt">drilling</span> proposal was submitted to the Integrated Ocean <span class="hlt">Drilling</span> Program (IODP) by 1 August 2011 and our preparation for the operation began in parallel. To reach the plate boundary target, and to install an observatory, we had to develop several new tools (e.g., a casing running tool). The strength and performance of the <span class="hlt">drill</span> string was also a major technical and engineering issue. Taking the limitations of the operational time window into account, our original strategy was, in about 7,000 m of water depth near the axis of the Japan Trench, to 1) <span class="hlt">drill</span> a 8-1/2" hole with LWD and install an observatory 900 m below the seafloor, 2) <span class="hlt">drill</span> a 10-5/8" hole with <span class="hlt">coring</span> assembly and collect <span class="hlt">core</span> samples from the deeper part of the hole then install another observatory 900 m below the seafloor. IODP Expedition 343 (JFAST) started on 1 April 2012 (less than 13 months after the earthquake). Several mechanical and weather issues prohibited completion of the above planned operations but we had reached the following operational targets by the end of this expedition of 24 May 2012: 1. Penetrated 850.5 m below seafloor and obtained <span class="hlt">geophysical</span> data by LWD which allowed the plate boundary interface to be located. 2. Collected <span class="hlt">core</span> samples from 648 m to 844.5 m below the seafloor, including samples of the plate boundary fault zone. Both operations were completed in water depth of 6889.5 m. However, due to a lack of operational time, the installation of temperature observatories was not performed. Consequently, IODP and CDEX/JAMSTEC decided to return to the site, in a follow-up expedition (IODP Expedition 343T), to install a temperature observatory into a borehole started by the original part of the expedition. IODP Expedition 343T began on 5 July 2012 and successfully installed a temperature observatory into an 854.8 m borehole in 6,897.5 m of water, operations completed on 19 July 2012.</p> <div class="credits"> <p class="dwt_author">Eguchi, N.; Toczko, S.; Maeda, L.; Sawada, I.; Saruhashi, T.; Kyo, N.; Namba, Y.; Chester, F.; Mori, J. J.; Science Party, I.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">340</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/474860"> <span id="translatedtitle"><span class="hlt">Core</span>-tube data logger</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Wireline <span class="hlt">core</span> <span class="hlt">drilling</span>, increasingly used for geothermal exploration, employs a <span class="hlt">core</span>-tube to capture a rock <span class="hlt">core</span> sample during <span class="hlt">drilling</span>. Three types of <span class="hlt">core</span>-tube data loggers (CTDL) have been built and tested to date by Sandia national Laboratories. They are: (1) temperature-only logger, (2) temperature/inclinometer logger and (3) heat-shielded temperature/inclinometer logger. All were tested during <span class="hlt">core</span> <span class="hlt">drilling</span> operations using standard wireline diamond <span class="hlt">core</span> <span class="hlt">drilling</span> equipment. While these tools are designed for <span class="hlt">core</span>-tube deployment, the tool lends itself to be adapted to other <span class="hlt">drilling</span> modes and equipment. Topics covered in this paper include: (1) description on how the CTDLs are implemented, (2) the components of the system, (3) the type of data one can expect from this type of tool, (4) lessons learned, (5) comparison to its counterpart and (6) future work.</p> <div class="credits"> <p class="dwt_author">Henfling, J.A.; Normann, R.A.; Knudsen, S.; Drumheller, D.</p> <p class="dwt_publisher"></p> <p class="publishDate">1997-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_16");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" 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<a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a style="font-weight: bold;">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_19");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">341</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=DE85009549"> <span id="translatedtitle">Thermal Spallation <span class="hlt">Drilling</span>.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">Thermal spallation <span class="hlt">drilling</span> is an underdeveloped process with great potential for reducing the costs of <span class="hlt">drilling</span> holes and mining shafts and tunnels in most very hard rocks. Industry has used this process to <span class="hlt">drill</span> blast holes for emplacing explosives and ...</p> <div class="credits"> <p class="dwt_author">R. E. Williams</p> <p class="dwt_publisher"></p> <p class="publishDate">1985-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">342</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.agu.org/journals/jb/v087/iB08/JB087iB08p06631/JB087iB08p06631.pdf"> <span id="translatedtitle">Hydrofracturing stress measurements in the Iceland Research <span class="hlt">Drilling</span> Project <span class="hlt">drill</span> hole at Reydarfjordur, Iceland</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Two independent suites of hydrofracturing stress measurements were conducted in the top 600 m of the Iceland Research <span class="hlt">Drilling</span> Project deep hole at Reydarfjordur, east Iceland. As indicated by the continuously extracted <span class="hlt">drill</span> <span class="hlt">core</span>, the tested section consists of tertiary subaerial tholeiitic lava flows cut by many basaltic dikes. The density of the basalt was used to estimate the vertical</p> <div class="credits"> <p class="dwt_author">Bezalel C. Haimson; Fritz Rummel</p> <p class="dwt_publisher"></p> <p class="publishDate">1982-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">343</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=ADA031745"> <span id="translatedtitle">Rheological Implications of the Internal Structure and Crystal Fabrics of the West Antarctic Ice Sheet as Revealed by Deep <span class="hlt">Core</span> <span class="hlt">Drilling</span> at Byrd Station.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">Crystalline textures and fabrics of ice <span class="hlt">cores</span> from the 2164-m-thick ice sheet at Byrd Station, Antarctica, reveal the existence of an anisotropic ice sheet. A gradual but persistent increase in the c-axis preferred orientation of the ice crystals was obse...</p> <div class="credits"> <p class="dwt_author">A. J. Gow T. Williamson</p> <p class="dwt_publisher"></p> <p class="publishDate">1976-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">344</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19770016834&hterms=home+automation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dhome%2Bautomation"> <span id="translatedtitle"><span class="hlt">Drill</span> user's manual. [<span class="hlt">drilling</span> machine automation</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p class="result-summary">Instructions are given for using the <span class="hlt">DRILL</span> computer program which converts data contained in an Interactive Computer Graphics System (IGDS) design file to production of a paper tape for driving a numerically controlled <span class="hlt">drilling</span> machine.</p> <div class="credits"> <p class="dwt_author">Pitts, E. A.</p> <p class="dwt_publisher"></p> <p class="publishDate">1976-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">345</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/242244"> <span id="translatedtitle"><span class="hlt">Drilling</span> technology, 2000</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Great strides have been made in <span class="hlt">drilling</span> during the nineties, but many operators are unaware of many of the exciting capabilities and potential offered by today` <span class="hlt">drilling</span> technology. As people move toward the year 2000, they see <span class="hlt">drilling</span> providers refine these capabilities, broaden their applications, and increase operator awareness of their availability and usefulness. Thus, to see where <span class="hlt">drilling</span> will be in the year 2000, people need to look at where the <span class="hlt">drilling</span> forefront lies today. This paper discusses the trends in technology associated with horizontal <span class="hlt">drilling</span>, re-entry techniques, coiled-tubing, extended-reach <span class="hlt">drilling</span>, multilateral <span class="hlt">drilling</span> and general well development technologies.</p> <div class="credits"> <p class="dwt_author">Offenbacher, L.</p> <p class="dwt_publisher"></p> <p class="publishDate">1996-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">346</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/doepatents/biblio/7027163"> <span id="translatedtitle">Fiber optic <span class="hlt">geophysical</span> sensors</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p class="result-summary">A fiber optic <span class="hlt">geophysical</span> sensor is described in which laser light is passed through a sensor interferometer in contact with a <span class="hlt">geophysical</span> event, and a reference interferometer not in contact with the <span class="hlt">geophysical</span> event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects. 2 figures.</p> <div class="credits"> <p class="dwt_author">Homuth, E.F.</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-03-19</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">347</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6914033"> <span id="translatedtitle">High temperature <span class="hlt">geophysical</span> instrumentation</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The instrumentation development program was to proceed in parallel with scientific research and was driven by the needs of researchers. The development of these instruments has therefore included numerous <span class="hlt">geophysical</span> field tests, many of which have resulted in the publication of scientific articles. This paper is a brief summary of some of the major <span class="hlt">geophysical</span> instruments that have been developed and tested under the High Temperature <span class="hlt">Geophysics</span> Program. These instruments are briefly described and references are given for further detailed information and for scientific papers that have resulted from the use of these instruments. 9 refs., 14 figs.</p> <div class="credits"> <p class="dwt_author">Hardee, H.C.</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-06-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">348</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6890887"> <span id="translatedtitle"><span class="hlt">Geophysics</span> I. Seismic Methods</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">During the past two decades, the technology of <span class="hlt">geophysics</span> has exploded. At the same time, the petroleum industry has been forced to look for more and more subtle traps in more and more difficult terrain. The choice of papers in this <span class="hlt">geophysics</span> reprint volume reflects this evolution. The papers were chosen to help geologists, not geophysicists, enhance their knowledge of <span class="hlt">geophysics</span>. Math-intensive papers were excluded because those papers are relatively esoteric and have limited applicability for most geologists. This volume concentrates on different seismic survey methods. Each of the 38 papers were abstracted and indexed for the U.S. Department of Energy's Energy Data Base.</p> <div class="credits"> <p class="dwt_author">Beaumont, E.A.; Foster, N.H. (comps.)</p> <p class="dwt_publisher"></p> <p class="publishDate">1989-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">349</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20050166970&hterms=bioassay&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2522bioassay%2522"> <span id="translatedtitle">Searching for Life Underground: An Analysis of Remote Sensing Observations of a <span class="hlt">Drill</span> <span class="hlt">Core</span> from Rio Tinto, Spain for Mineralogical Indications of Biological Activity</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p class="result-summary">Water is unstable on the surface of Mars, and therefore the Martian surface is not likely to support life. It is possible, however, that liquid water exists beneath the surface of Mars, and thus life might also be found in the subsurface. Subsurface life would most likely be microbial, anaerobic, and chemoautotrophic; these types of biospheres on Earth are rare, and not well understood. Finding water and life are high priorities for Mars exploration, and therefore it is important that we learn to explore the subsurface robotically, by <span class="hlt">drilling</span>. The Mars Analog Rio Tinto Experiment (MARTE), has searched successfully for a subsurface biosphere at Rio Tinto, Spain [1,2,3,4]. The Rio Tinto study site was selected to search for a subsurface biosphere because the extremely low pH and high concentrations of elements such as iron and copper in the Tinto River suggest the presence of a chemoautotrophic biosphere in the subsurface beneath the river. The Rio Tinto has been recognized as an important mineralogical analog to the Sinus Meridiani site on Mars [5].</p> <div class="credits"> <p class="dwt_author">Battler, M.; Stoker, C.</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">350</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2005AGUFMIN44A..04R"> <span id="translatedtitle">International Collaboration in Data Management for Scientific Ocean <span class="hlt">Drilling</span>: Preserving Legacy Data While Implementing New Requirements.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Integrated Ocean <span class="hlt">Drilling</span> Program (IODP: 2003-2013 initial phase) is the successor to the Deep Sea <span class="hlt">Drilling</span> Project (DSDP: 1968-1983) and the Ocean <span class="hlt">Drilling</span> Program (ODP: 1985-2003). These earlier scientific <span class="hlt">drilling</span> programs amassed collections of sediment and rock <span class="hlt">cores</span> (over 300 kilometers stored in four repositories) and data organized in distributed databases and in print or electronic publications. International members of the IODP have established, through memoranda, the right to have access to: (1) all data, samples, scientific and technical results, all engineering plans, data or other information produced under contract to the program; and, (2) all data from <span class="hlt">geophysical</span> and other site surveys performed in support of the program which are used for <span class="hlt">drilling</span> planning. The challenge that faces the individual platform operators and management of IODP is to find the right balance and appropriate synergies among the needs, expectations and requirements of stakeholders. The evolving model for IODP database services consists of the management and integration of data collected onboard the various IODP platforms (including downhole logging and syn-cruise site survey information), legacy data from DSDP and ODP, data derived from post-cruise research and publications, and other IODP-relevant information types, to form a common, program-wide IODP information system (e.g., IODP Portal) which will be accessible to both researchers and the public. The JANUS relational database of ODP was introduced in 1997 and the bulk of ODP shipboard data has been migrated into this system, which is comprised of a relational data model consisting of over 450 tables. The JANUS database includes paleontological, lithostratigraphic, chemical, physical, sedimentological, and <span class="hlt">geophysical</span> data from a global distribution of sites. For ODP Legs 100 through 210, and including IODP Expeditions 301 through 308, JANUS has been used to store data from 233,835 meters of <span class="hlt">core</span> recovered, which are comprised of 38,039 <span class="hlt">cores</span>, with 202,281 <span class="hlt">core</span> sections stored in repositories, which have resulted in the taking of 2,299,180 samples for scientists and other users (http://iodp.tamu.edu/janusweb/general/dbtable.cgi). JANUS and other IODP databases are viewed as components of an evolving distributed network of databases, supported by metadata catalogs and middleware with XML workflows, that are intended to provide access to DSDP/ODP/IODP <span class="hlt">cores</span> and sample-based data as well as other distributed geoscience data collections (e.g., CHRONOS, PetDB, SedDB). These data resources can be explored through the use of emerging data visualization environments, such as GeoWall, <span class="hlt">Core</span>Wall (http://(www.evl.uic.edu/cavern/corewall), a multi-screen display for viewing <span class="hlt">cores</span> and related data, GeoWall-2 and LambdaVision, a very-high resolution, networked environment for data exploration and visualization, and others. The U.S Implementing Organization (USIO) for the IODP, also known as the JOI Alliance, is a partnership between Joint Oceanographic Institutions (JOI), Texas A&M University, and Lamont-Doherty Earth Observatory of Columbia University. JOI is a consortium of 20 premier oceanographic research institutions that serves the U.S. scientific community by leading large-scale, global research programs in scientific ocean <span class="hlt">drilling</span> and ocean observing. For more than 25 years, JOI has helped facilitate discovery and advance global understanding of the Earth and its oceans through excellence in program management.</p> <div class="credits"> <p class="dwt_author">Rack, F. R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">351</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/54295322"> <span id="tr