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Articles 1921 - 1950 of 2452

Full-Text Articles in Geophysics and Seismology

Geology And Petrochemistry Of The Mount Chase Massive Sulfide Prospect, Penobscot County, Maine, Michael V. Scully Jan 1989

Geology And Petrochemistry Of The Mount Chase Massive Sulfide Prospect, Penobscot County, Maine, Michael V. Scully

Masters Theses

"The Mount Chase massive sulfide prospect of northern Penobscot County, Maine was discovered in 1979 by Getty Mining Company. The deposit occurs within a sequence of lower paleozoic metavolcanic and metasedimentary rocks. The footwall units consist of rhyolitic flows, quartz-feldspar crystal tuff, and altered tuffaceous volcanic breccias. These rocks lie unconformably upon intensely folded sediments which are tentatively correlated with the Grand Pitch Formation of probable Cambrian age. The footwall volcanoclastic rocks exhibit a narrow zone of intense chloritic alteration immediately below the massive sulfide horizon, and a broader zone of sericitic alteration below that. A zone of stringer mineralization …


A Seismic Analysis Of Reefs In The Traverse Limestone Of Allegan County, Michigan, William Charles Henderson Dec 1988

A Seismic Analysis Of Reefs In The Traverse Limestone Of Allegan County, Michigan, William Charles Henderson

Masters Theses

A seismic reflection study was performed across the Diamond Springs oil field in Allegan County, Michigan. The horizon of interest was the Middle Devonian Traverse Limestone located 1,700 feet in the subsurface. Within the Traverse Limestone are scattered patch reefs which characterize a targeted reservoir. The use of high-resolution, shallow seismic reflection techniques are useful for defining detailed subsurface porosity zones within the patch reef reservoirs.

Common source-offset profiling utilizing high-frequency sources and proper determination of field parameters are important in obtaining the desired optimum reflection. Also, the use of synthetic seismograms for modeling waveforms is essential for identifying the …


Central Utah Regional Seismotectonic Study, U.S. Deparment Of The Interior, Bureau Of Reclamation Mar 1988

Central Utah Regional Seismotectonic Study, U.S. Deparment Of The Interior, Bureau Of Reclamation

Elusive Documents

This report presents the results of a Bureau of Reclamation seismotectonic

evaluation for dams in the Wasatch Mountains in north-central Utah. The

major objectives of this study were to identify potential earthquake sources

in the region and to estimate MCEs (maximum credible earthquakes) for these

sources. The conclusions presented in this report are based on geologic

mapping, trenching, study of aerial photography, mapping and correlation of

Quaternary deposits, soil profile descriptions and sampling, and analysis of

historic seismicity. The Regional Study area includes an area on the eastern

margin of the Basin and Range province that extends east from the …


Contributions To The Quaternary Geology Of Northern Maine And Adjacent Canada, J. Steven Kite (Ed.), Thomas V. Lowell (Ed.), Woodrow B. Thompson (Ed.) Jan 1988

Contributions To The Quaternary Geology Of Northern Maine And Adjacent Canada, J. Steven Kite (Ed.), Thomas V. Lowell (Ed.), Woodrow B. Thompson (Ed.)

Maine Collection

Contributions to the Quaternary Geology of Northern Maine and Adjacent Canada

Bulletin 37 - Maine Geological Survey, Department of Conservation,

Augusta, Maine 04333 (1988).

Contents: Introduction / A GEOMORPHIC METHOD FOR RECONSTRUCTING PALEO ICE SHEETS, Part I: GLACIAL GEOLOGY. - T. Hughes and J. Fastook / A GEOMORPHIC METHOD FOR RECONSTRUCTING PALEO ICE SHEETS, Part II: GLACIOLOGY. - J. Fastook and T. Hughes / TILL STRATIGRAPHY AT THE BALD MOUNTAIN MINE SITE, NORTHERN MAINE - W. R. Holland and F. F. Bragdon / GLACIAL DISPERSAL FROM THE PRIESTLY LAKE AND DEBOULLIE PLUTONS, NORTHERN MAINE - E. F. Halter / GLACIATION …


A Seismic Reflection Survey Over The Wayne-25 Oil Field In Cass County, Michigan, Paul D. Horton Dec 1987

A Seismic Reflection Survey Over The Wayne-25 Oil Field In Cass County, Michigan, Paul D. Horton

Masters Theses

The "optimum window" seismic reflection method was used in an endeavor to further define an oil producing structure in the Traverse Limestone. This method entails using a source-geophone offset which allows desired reflections to arrive in an undisturbed time zone.

Several sources in the study area produced seismic pulses with relatively high dominant frequency components ranging from 80 to 120 hertz. However, only small charges of dynamite produced sufficient energy to penetrate the glacial drift in the study area.

Preliminarily identified reflection arrivals from the targeted horizon were consistently masked in seismic profiling records by high amplitude, low velocity seismic …


Geology, Geochemistry, And Geochronology Of The Lems Ridge Olistostrome, Klamath Mountains, California, Matthias Ohr Jan 1987

Geology, Geochemistry, And Geochronology Of The Lems Ridge Olistostrome, Klamath Mountains, California, Matthias Ohr

Geology Theses and Dissertations

The Lems Ridge olistostrome (LRO), located within the western Jurassic belt of the Klamath Mountains geologic province, is a melange unit showing a distinct block-in-matrix fabric. The conformable relationship to both an igneous basement and the overlying flysch of the Late Jurassic Galice Formation points to a sedimentary origin. The lack of pervasive deformation and the internal stratification also support a predominantly olistostromal origin of the LRO. The matrix of the LRO consists of pebbly mudstone which interfingers with tuffaceous greenstone and tuff-breccias. Subordinate beds of chert, argillite, and sandstone are also present. The matrix contains abundant ophiolitic clasts, fragments …


Lithofacies Analysis Of The Lamotte Sandstone In South Central Missouri, Michael Gerard Kraenzle Jan 1987

Lithofacies Analysis Of The Lamotte Sandstone In South Central Missouri, Michael Gerard Kraenzle

Masters Theses

"Based on the analysis of thirty-one cores obtained from the Missouri Department of Natural Resources in Rolla, the upper Cambrian Lamotte Sandstone in South Central Missouri has been divided into six sedimentary facies ranging from alluvial fan and braided stream to open marine.

The Lamotte Sandstone is the basal Cambrian sandstone found throughout most of the state of Missouri. It directly overlies late Precambrian (1.4 to 1.5 billion year old) granites and metasediments. The Lamotte and overlying Bonneterre Formations are generally considered to have been deposited by a transgression which occurred during the Late Cambrian Period (Croixian Epoch).

The Lamotte …


A Gravity And Magnetic Study Of The Crooked Creek Cryptoexplosion Structure, Crawford County, Missouri, Charles Edward Woodbury Jan 1987

A Gravity And Magnetic Study Of The Crooked Creek Cryptoexplosion Structure, Crawford County, Missouri, Charles Edward Woodbury

Masters Theses

"The pre-Pennsylvanian structure at Crooked Creek consists of a complex, vertically faulted ring of Cambrian and Ordovician sediments with a central uplifted core. The center of the structure is strongly deformed and contains shatter cones, brecciation, and other signs of extreme shock.

A magnetic low over the center of the structure suggests that igneous material was not involved in the formation of the structure, and this is corroborated by core analysis. Gravity data indicates several small gravity lows, possibly associated with areas of brecciation, circling the flanks of the structure. As in the magnetic data, there is no indication that …


A Paleoenvironmental Study Of The Salem Limestone In The Vicinity Of St. Louis, Missouri, Douglas J. Van Brunt Jan 1987

A Paleoenvironmental Study Of The Salem Limestone In The Vicinity Of St. Louis, Missouri, Douglas J. Van Brunt

Masters Theses

“The Salem Limestone (Meramecian) of Mississippian age in the vicinity of St. Louis, Missouri is composed of a variable sequence of limestones deposited in shallow waters adjacent to scattered positive elements. This unit varies in thickness from zero up to 160 feet.

A medium to coarse-grained calcarenite is the dominant rock-type of the thesis area and is most abundant in the central and southwest regions. Stratigraphic sections in the northern region are more dolomitic, increasingly brecciated, and contains numerous secondary features. The southeast region is thinly bedded and composed of greater amounts of micrite formed by algal activity or direct …


A Petrographic Investigation Of The Rhythmically Bedded Upper Fayetteville Formation (Mississippian) In Northern Arkansas, Edith Ann Starbuck Jan 1987

A Petrographic Investigation Of The Rhythmically Bedded Upper Fayetteville Formation (Mississippian) In Northern Arkansas, Edith Ann Starbuck

Masters Theses

"The upper Mississippian Fayetteville Formation in northern Arkansas is primarily a calcareous black shale, but in some localities the upper one third to one half of the formation is made up of alternating black shales and limestones. Comparable lithologies have been suggested by some (Hallam, Ricken, Kent, and Sujkowski) to have been created by the diagenetic segregation of carbonate from calcareous shale.

Petrographic thin section analysis reveals that the lowest limestone beds of the rhythmic upper Fayetteville are made up almost entirely of microspar and all fossil material is recrystallized, even to the point of obliteration in some cases. The …


Development And Application Of Some Quantitative Stratigraphic Techniques To The Coos Bay Coalfield, A Tertiary Fluvio-Deltaic Complex In Southwestern Oregon, Willard Sidney Titus Iii Jan 1987

Development And Application Of Some Quantitative Stratigraphic Techniques To The Coos Bay Coalfield, A Tertiary Fluvio-Deltaic Complex In Southwestern Oregon, Willard Sidney Titus Iii

Dissertations and Theses

A computer technique for interpreting geophysical logs of drill-holes in quantitative lithologic terms has been developed and tested on the deposits of the late Eocene Coaledo Formation, a well-studied fluvio-deltaic complex in southwestern Oregon. The technique involves the use of induced and natural gamma logs for separation of coal and claystone from coarse-grained detrital rocks and the use of the ratio of resistivity and natural gamma responses (defined here as the "grain size index") to divide the coarse elastic rocks into a series of textural classes corresponding to the Wentworth-Odden particle size scale.


A Seismic Refraction Study Of A Portion Of The Northeastern Margin Of The Tualatin Valley, Oregon, David John Nazy Jan 1987

A Seismic Refraction Study Of A Portion Of The Northeastern Margin Of The Tualatin Valley, Oregon, David John Nazy

Dissertations and Theses

The Tualatin Valley is a well defined elliptical basin centered at Hillsboro, with a major axis trending roughly N65°W. The valley is bordered on the northeast by the Tualatin Mountains (Portland Hills) which are a faulted, northwest-trending asymmetrical anticline. Topographic and geophysical evidence have defined the Portland Hills fault, which occurs along the northeast side of the Tualatin Mountains. The possibility that a fault or fault zone occurs along the southwest side of the Tualatin Mountains was investigated in this study.


Simulating A Large Wasatch Front, Utah, Earthquake Using Small Earthquake Recordings As Green's Functions, United States Department Of Defense, Air Force Geophysics Laboratory May 1986

Simulating A Large Wasatch Front, Utah, Earthquake Using Small Earthquake Recordings As Green's Functions, United States Department Of Defense, Air Force Geophysics Laboratory

Geology

Several earthquake recordings at Golden, Colorado in the magnitude range 4-6, were digitized and were used to investigate the feasibility of adding them together to simulate a larger earthquake (magnitude 7.0-7.5). The test path of the Wasatch Front, Utah to the WWSSN station at Golden was selected (distance=400-500 km). The hypothetical causative fault was given dimensions on the order of 45 km long by 20 km wide and was divided into "cells," representative in size to the "seed" events rupture dimensions and with other variations. The results were evaluated by total energy and amplitude criteria. The final waveforms were judged …


Transient Electromagnetic Sounding For Groundwater, David V. Fitterman, Mark T. Stewart Apr 1986

Transient Electromagnetic Sounding For Groundwater, David V. Fitterman, Mark T. Stewart

Geology Faculty Publications

The feasibility of using the transient electromagnetic sounding (TS or TDEM) method for groundwater exploration can be studied by means of numerical models. As examples of its applicability to groundwater exploration, we study four groundwater exploration problems: (1) mapping of alluvial fill and gravel zones over bedrock; (2) mapping of sand and gravel lenses in till; (3) detection of salt or brackish water interfaces in freshwater aquifers; and (4) determination of hydrostratigraphy. These groundwater problems require determination of the depth to bedrock; location of resistive, high-porosity zones associated with fresh water; determination of formation resistivity to assess water quality; and …


On The Linear Relation Between Mb And Ms For Discrimination Between Explosions And Earthquakes, Ali A. Nowroozi Jan 1986

On The Linear Relation Between Mb And Ms For Discrimination Between Explosions And Earthquakes, Ali A. Nowroozi

OES Faculty Publications

Summary. The statistical capability of the mb :Ms, discriminant for the discrimination of earthquake and explosion populations is examined by application of discriminant functions to a group of 83 explosions and 72 earthquakes in Eurasia. Equations are derived for the probability that an event is an earthquake or an explosion. The positive sign of DIS in the decision index equation,

DIS, = 34.3383 - 11.9569 mbi, + 7.1 161 Msi,

indicates that the event i is an earthquake. Its negative sign indicates that event i is an explosion. The probability of …


The Physics Of The Antarctic Circumpolar Current, Worth D. Nowlin, John M. Klinck Jan 1986

The Physics Of The Antarctic Circumpolar Current, Worth D. Nowlin, John M. Klinck

CCPO Publications

A region of transition of surface water characteristics from subantarctic to Antarctic and an associated eastward flowing Antarctic Circumpolar Current (ACC) have long been recognized to exist as a band around Antarctica. In this review we summarize the most important observational and theoretical findings of the past decade regarding the ACC, identify gaps in our knowledge, and recommend studies to address these. The nature of the meridional zonation of the ACC is only now being revealed. The ACC seems to exist as multiple narrow jets imbedded in, or associated with, density fronts (the Subantarctic and Polar fronts) which appear to …


Geology Of The Escalante District, Iron County, Utah, James William Biehl Jan 1986

Geology Of The Escalante District, Iron County, Utah, James William Biehl

Masters Theses

"The Escalante Silver District, Iron County, Utah, occupies a group of low hills extending to the Escalante Desert from the Black Hills to the south. Tertiary volcanics serve as host rocks for silver bearing quartz veins. Five map units, with a total of 12 members are recognized. X-ray fluorescence and field mapping enabled differentiation of the units, while thin section analysis enabled characterization of the members. The map units formed in three episodes. The oldest is extrusive doming of distinctive older lava and breccia flows. The middle group is made up of tectontic breccias, sillar-like lava flows, and volcaniclastic sediments …


The Use Of Electrical Resistivity To Delineate A Brine Contamination Plume In The Walker Oilfield, Kent County, Michigan, Kent E. Meisel Dec 1985

The Use Of Electrical Resistivity To Delineate A Brine Contamination Plume In The Walker Oilfield, Kent County, Michigan, Kent E. Meisel

Masters Theses

Contamination of groundwater with oil field brines was reported in the Walker Oil Field, Michigan. An electrical resistivity survey utilizing the Vertical Electrical Sounding method was conducted to test the method as an exploratory tool for delineating brine contamination in glacial deposits. The method was successful in defining the subsurface geology and delineating a shallow, confined aquifer, but the presence of extensive, conductive clays effectively masked the presence of brine contamination. The method was shown to be an effective exploratory tool for shallow investigations.


A Geophysical Model Of The Gravity-Magnetic High, Virginia Coastal Plan, Gordon Everett Davison Apr 1985

A Geophysical Model Of The Gravity-Magnetic High, Virginia Coastal Plan, Gordon Everett Davison

OES Theses and Dissertations

The coastal plain province of Virginia is characterized by a coincidental gravity and magnetic high separating Appalachian-trend geophysical signatures to the west from non-Appalachian signatures to the east. Two cross-trend gravity and magnetic profiles, one on the Northern Neck of Virginia and one along Interstate Highway 64, were used to interpret the anomalous high. The profile models suggests that the anomaly is characterized by high-density, variably magnetic, east-dipping (60°) crustal blocks. Further information from well-logs indicate that the anomaly is due to meta-mafic rocks of oceanic origin, flanked by low-density, lower susceptibility, granitic units. This suggests that the anomalous gravity-magnetic …


Fault Movements And Tectonics Of Eastern Iran: Boundaries Of The Lut Plate, Ali A. Nowroozi, A. Mohajer-Ashjai Jan 1985

Fault Movements And Tectonics Of Eastern Iran: Boundaries Of The Lut Plate, Ali A. Nowroozi, A. Mohajer-Ashjai

OES Faculty Publications

Summary. From 1977 March 21 to 1981 July 28, about 15 earthquakes with Ms ≥6.0 and many earthquakes with Ms≥4.5 have occurred in Iran. The upsurge of seismic activity started following the Khorqu earthquake of 1977 March 21, M,=7.0, south-east of the Fars folded series of Zagros. This shock had a thrust focal mechanism solution indicating the general northward movement of the Arabian plate with respect to the Iranian landmass. It was followed by six major damaging earthquakes in eastern Iran. The earthquakes are associated with extensive faulting which surrounds the Lut plate. (1) The Zarand earthquake …


Carbonate Facies Of The Kimmswick Limestone (Trenton/Galena) In Southwestern Illinois : Their Relations As Oil Reservoirs And Traps, Gregory A. Crews Jan 1985

Carbonate Facies Of The Kimmswick Limestone (Trenton/Galena) In Southwestern Illinois : Their Relations As Oil Reservoirs And Traps, Gregory A. Crews

Masters Theses

"Four potentially productive oil horizons have been identified in the Kimmswick Limestone (Trenton/Galena), Ordovician of southwestern Illinois. Four non-porous caprock zones and four porous horizons were identified and informally named after corresponding members of the Dunleith Formation (Illinois State Geological Survey classification). The porous horizons generally consist of coarse-grained, fossiliferous limestone, which is overlain by finer grained, spar-cemented, impermeable limestone.

In order of production potential, the horizons are the upper Moredock, lower Moredock, Beecher-St. James (lowermost stratigraphic unit), and New London (uppermost stratigraphic unit). Porosity in the upper Moredock horizon is relatively consistent throughout the study area, as determined by …


Tectonic Implications Of Late Tertiary Strata Exposed Along The Piankatank River, Eastern Virginia, Daniel Stephen Lane Oct 1984

Tectonic Implications Of Late Tertiary Strata Exposed Along The Piankatank River, Eastern Virginia, Daniel Stephen Lane

OES Theses and Dissertations

Biostratigraphic analysis of Late Miocene and Pliocene strata along the Piankatank River in eastern Virginia exposes a juxtaposition of the Eastover and Yorktown Formations. This structure is situated on a NE trending alignment of geological, geomorphic, and geophysical features which run from southern Virginia to northern Delaware. Tectonic jointing in isolated sandstone bodies and fracture controlled drainage patterns provide further evidence of post-middle Pliocene tectonism in the region. The lateral spacing of this structure from the Stafford and Brandywine fault zones and other linear features on the Coastal Plain strongly implies that a structural similarity exists between the Piankatank structure …


Land Use Effects On Shallow Earth Resistivity, Gary James Barton Aug 1984

Land Use Effects On Shallow Earth Resistivity, Gary James Barton

Masters Theses

No abstract provided.


A High-Resolution Bathymetry Map For The Marguerite Bay And Adjacent West Antarctic Peninsula Shelf For The Southern Ocean Globec Program, S. T. Bolmer, R. C. Beardsley, C. Pudsey, P. Morris, P. Wiebe, Eileen E. Hofmann, J. Anderson, A. Maldonado May 1984

A High-Resolution Bathymetry Map For The Marguerite Bay And Adjacent West Antarctic Peninsula Shelf For The Southern Ocean Globec Program, S. T. Bolmer, R. C. Beardsley, C. Pudsey, P. Morris, P. Wiebe, Eileen E. Hofmann, J. Anderson, A. Maldonado

OES Faculty Publications

One objective of the U.S. Southern Ocean Global Ocean Ecosystems Dynamics (SO GLOBEC) program is to gain a better understanding of the sea floor bathymetry in the program study area. Much of Marguerite Bay and the adjacent shelf west of the Antarctic Peninsula were poorly charted when the SO GLOBEC program started in 2000. Before the first SO GLOBEC cruise, an improved local area version (ETOPO8.2A) was created from the Smith and Sandwell (1997) topo_8.2.img 2-minute digital gridded bathymetry for the study area. The first SO GLOBEC mooring cruise on the R/V Lawrence M. Gould (March 2001) showed that the …


A Geophysical Investigation Of A Possible Astrobleme In Southwestern Michigan, Suhas L. Ghatge Apr 1984

A Geophysical Investigation Of A Possible Astrobleme In Southwestern Michigan, Suhas L. Ghatge

Masters Theses

A circular pattern to the oil production in Calvin Township, Cass County, Michigan, absence of about 1200 feet of Ordovician sediments and uplift indicated by a deep drill hole in the center of the productive area and absence of anomalies on the regional gravity and magnetic maps led to detailed gravity and magnetic surveys over this structure to delineate it and provide information regarding its genesis.

The Bouguer gravity and magnetic anomaly maps show no anomaly associated with the structure. The 28-mile wavelength second harmonic residual gravity and magnetic maps show linear features in the area. Two dimensional gravity modeling …


Lithology And Sedimentology Of The Graydon Springs Channel, Pennsylvanian Of Southwestern Missouri, Gregory Lee Easson Jan 1984

Lithology And Sedimentology Of The Graydon Springs Channel, Pennsylvanian Of Southwestern Missouri, Gregory Lee Easson

Masters Theses

"The Graydon Springs Member of Southwest Missouri, here assigned to the Warner Formation of Pennsylvanian age was sampled and examined in order to document the lithology, sedimentology, source area, stratigraphic position, and overall geologic history of these channel-like bodies. The member is composed of an upper sandstone unit and a lower conglomerate unit.

Laboratory investigations of thin sections indicate that the sandstone unit is composed of well sorted, well rounded quartz and minor amounts of accessory minerals cemented with iron oxide, commonly hematite. Field observations indicate that the conglomerate unit is composed of very poorly sorted, very well rounded chert …


Relation Of Bitumen To Ore In The Magmont West Orebody, Southeast Missouri, Mark Alan Marikos Jan 1984

Relation Of Bitumen To Ore In The Magmont West Orebody, Southeast Missouri, Mark Alan Marikos

Masters Theses

"Bitumen in the form of oil blebs from the Magmont West orebody of the Viburnum Trend was examined and analysed in an attempt to relate hydrocarbon distribution and origin to ore genesis. Hydrogen, carbon, nitrogen, sulfur and oxygen percentages were determined by elemental analyses. Trace element composition was determined by emmission spectroscopy and the composition of the bitumen was calculated with respect to aromatic hydrocarbons, saturated hydrocarbons and NSO (nitrogen-sulfur-oxygen) components. The bitumen and kerogen from associated shale samples were evaluated by Rock-Eval pyrolysis and pyrolysis-gas chromatography.

The bitumen was calculated to be approximately 40 to 50 percent aromatic and …


Oil Producing Upper Cherokee And Lower Marmaton (Pennsylvanian) Channel Sandstones Of Jackson And Cass Counties, Missouri, Stephen Thomas Carroll Jan 1984

Oil Producing Upper Cherokee And Lower Marmaton (Pennsylvanian) Channel Sandstones Of Jackson And Cass Counties, Missouri, Stephen Thomas Carroll

Masters Theses

"Approximately 240 gamma ray-neutron logs were interpreted and correlated in an attempt to isolate separate channels collectively referred to as "Squirrel" sands in the upper Cherokee and lower Marmaton (Pennsylvanian) rocks of Jackson and Cass counties, Missouri. Isopach maps were prepared for two of the identifiable fluvial sandstones and a structure map was drawn on the laterally extensive Anna Shale.

The term "Squirrel" has been applied to as many as five different sandstone packages, and thus, has been the source of a great deal of confusion. In an attempt to sort out the confusion this thesis recognizes and defines three …


A Magnetic And Resistivity Survey Of Cork Street Landfill, Stanislaw Leja Dec 1983

A Magnetic And Resistivity Survey Of Cork Street Landfill, Stanislaw Leja

Masters Theses

Geophysical techniques such as magnetic and electrical resistivity methods are being increasingly applied in investigations of landfills.

For this survey, measurements of the intensity of the earth's magnetic field were taken at regular intervals along traverses. Resistivity readings were taken at selected intervals along the same or very similar traverses. Additional resistivity depth measurements or soundings were obtained at selected points in and around the landfill.

Profiles were analyzed for individual dump structures and for overall magnetic and resistivity response. Contour maps were drawn from the measurements at the site to depict broad trends or patterns. Deeper subsurface geology was …


Geophysical Strain And Tilt: Measurement Methodology And Analysis Of Data, Robert Mackay Aug 1983

Geophysical Strain And Tilt: Measurement Methodology And Analysis Of Data, Robert Mackay

Dissertations and Theses

Tilt and strain meters were installed on the Portland State University campus in the summer of 1982 and data was collected for 4 months. Instrument selection, operation, installation and performance are discussed.

Suggestions that could enhance data quality and data collection efficiency are presented.

An analysis procedure is suggested and an example of this procedure for an interval of data is discussed. The influence of the temperature, pressure, rainfall and solid earth tides on the signal is investigated, as well as the correlation between similar channels of the different tilt instruments. The temperature, rainfall and solid earth tides were all …