Skip to main content
Advanced Search

Filters: Tags: fracture (geologic) (X)

8 results (111ms)   

View Results as: JSON ATOM CSV
thumbnail
The U.S. Geological Survey (USGS), at the request of the U.S. Army Environmental Command (USAEC), evaluated the capabilities of two borehole technologies to measure horizontal groundwater velocity and direction of flow in a parallel-plate fractured-rock simulator. A colloidal borescope flowmeter (HB) and a heat-pulse flowmeter (HH) were deployed in 4-inch and 6-inch inner-diameter simulated uncased wells that spanned 0.39- and 1.0-inch apertures with simulated groundwater velocities ranging from 2 to 958 feet per day. Measurements were made at the USGS Hydrologic Instrumentation Facility in the Hydraulics Laboratory and the Indianapolis office of the USGS Ohio-Kentucky-Indiana Water Science Center. Ten measurements...
thumbnail
The heat-pulse flowmeter (HH) used in this testing is a KVA Model 200 system. The instrument computes groundwater vectors from heat arrival and decay in an array of four thermistors that surround a single heat source. An external compass attached to the top of the deployment system is used to orient the flowmeter in the borehole. The HH measured groundwater velocity and flow in the x-y plane. Fuzzy packers were filled with 0.08-inch diameter glass beads for all tests. The HH thermistors were centered over the simulated fracture during measurements. One to four measurements were made with the HH for each simulated flow.
thumbnail
The colloidal borescope flowmeter (HB) used in this testing was developed by AquaVISION, Llc. The instrument employs a charge-coupled device camera, an optical magnification lens (140x), and a light-emitting diode (LED) illumination source to visually track neutrally buoyant colloids (approximately 1-5 microns) moving horizontally through the borehole. The device measured groundwater velocity and flow direction in the x-y (horizontal) plane. The HB magnetometer was checked with a compass to assure proper instrument orientation before deployment into the simulators. Borescope data were collected for each flow condition for a period of at least 30 minutes. After data collection, borescope data were inspected for anomalous...
thumbnail
This release provides the data for a comprehensive survey of geologic structures in the eastern Española Basin of the Rio Grande rift, New Mexico. The release includes data and analyses from 53 individual fault zones and 22 other brittle structures, such as breccia zones, joints, and veins, investigated at a total of just over 100 sites. Structures were examined and compared from poorly lithified Tertiary sediments, as well as Paleozoic sedimentary and Proterozoic crystalline rocks. Data and analyses, include geologic maps; field observations and measurements; orientation, kinematic paleostress analyses and modeling; statistical examination of 575 fault trace lengths derived from aeromagnetic data in the Española...
Categories: Data; Types: Citation, Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: CGGSC, Crustal Geophysics and Geochemistry Science Center, Deformation (geologic), Faulting (geologic), Fracture (geologic), All tags...
thumbnail
These data are the basis of the figures in the manuscript "A Wideband magnetoresistive sensor for monitoring dynamic fault slip in laboratory fault friction experiments". That report was the result of an investigation of a non-contact, wideband method of sensing dynamic fault slip in laboratory geophysical experiments which employs an inexpensive magnetoresistive sensor, a small neodymium rare earth magnet, and user built application specific wideband signal conditioning electronics. The magnetoresistive sensor generates a voltage proportional to the changing angles of magnetic flux lines, generated by differential motion or rotation of the near-by magnet, through the sensor. The performance of an array of these...
thumbnail
The database for the Preliminary Geologic Map of the Cherry Hill Quadrangle, Dinwiddie, Sussex, and Greensville Counties, Virginia geographically straddles the Coastal Plain and Piedmont Provinces along the Tidewater Fall Line. Rocks of the eastern Piedmont Roanoke Rapids terrane crop out in the western part of the quadrangle and consist of greenschist- to amphibolite-facies Neoproterozoic felsic to intermediate metavolcanic rocks, some of which contain flattened quartz phenocrysts and are locally isoclinally folded; greenstone that is locally primary layered; and intrusive metadiorite and metagabbro, much of which has been altered to amphibolite. Most of these rocks are strongly foliated and jointed. Greenschist-facies...
Tags: Alluvial terrace, Alluvium, Amphibolite, Aplite, Atlantic coastal plain, All tags...
thumbnail
The effects of vertical flowmeter placement relative to the vertical fracture opening were examined using the colloidal borescope flowmeter (HB). For these measurements, the HB measurement interval was located at a depth equal to 0.5-inch above and below the top and bottom edges of the fracture, respectively; at upper and lower edge of the fracture; at the center of the fracture; and 0.25-inch above and below the center of the fracture. The HB measurement interval was radially centered in the borehole. For those tests, the simulated flow direction was 180, aperture was 1.0-inch and the velocity was held steady at 297 ft/d. This sub-study was intended to identify potential influence of turbulent eddies on measured...
thumbnail
The 1:100,000-scale geologic map database of the South Boston 30' × 60' quadrangle, Virginia and North Carolina, provides geologic information for the Piedmont along the I-85 and U.S. Route 58 corridors and in the Roanoke River watershed, which includes the John H. Kerr Reservoir and Lake Gaston. The Raleigh terrane (located on the eastern side of the map) contains Neoproterozoic to early Paleozoic(?) polydeformed, amphibolite-facies gneisses and schists. The Carolina slate belt of the Carolina terrane (located in the central part of the map) contains Neoproterozoic metavolcanic and metasedimentary rocks at greenschist facies. Although locally complicated, the slate-belt structure mapped across the South Boston...
Tags: 30 x 60 minute, Aaron Formation, Aarons Creek, Alkaline basalt, Allen Creek, All tags...


    map background search result map search result map Data for a Comprehensive Survey of Fault Zones, Breccias, and Fractures in and Flanking the Eastern Española Basin, Rio Grande Rift, New Mexico Data from the manuscript: A Wideband Magnetoresistive Sensor for Monitoring Dynamic Fault Slip in Laboratory Fault Friction Experiments Laboratory Assessment of Colloidal Borescope and Heat-Pulse Flowmeters in Measuring Horizontal Flow in Fractured-Rock Simulators Experimental Results for Vertical Placement of Colloidal Borescope Flowmeter Experimental Results for Colloidal Borescope Flowmeter Experimental Results for Heat-Pulse Flowmeter Database for the Preliminary Geologic Map of the Cherry Hill Quadrangle, Dinwiddie, Sussex, and Greensville Counties, Virginia Database for the Geologic Map of the South Boston 30' × 60' Quadrangle, Virginia and North Carolina Data from the manuscript: A Wideband Magnetoresistive Sensor for Monitoring Dynamic Fault Slip in Laboratory Fault Friction Experiments Database for the Preliminary Geologic Map of the Cherry Hill Quadrangle, Dinwiddie, Sussex, and Greensville Counties, Virginia Database for the Geologic Map of the South Boston 30' × 60' Quadrangle, Virginia and North Carolina Data for a Comprehensive Survey of Fault Zones, Breccias, and Fractures in and Flanking the Eastern Española Basin, Rio Grande Rift, New Mexico Laboratory Assessment of Colloidal Borescope and Heat-Pulse Flowmeters in Measuring Horizontal Flow in Fractured-Rock Simulators Experimental Results for Vertical Placement of Colloidal Borescope Flowmeter Experimental Results for Colloidal Borescope Flowmeter Experimental Results for Heat-Pulse Flowmeter