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Reed, George BruceApplication of kinematical geodesy for determining the short wave length components of the gravity field by satellite gradiometry /
Doctor of Philosophy, The Ohio State University, 1973, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Astronautics in geodesy;Geodetic satellites

Hanigan, Francis LawrenceTrilateration adjustment and network design : a critical compendium of methods and techniques proposed for the adjustment and design of trilaterated networks /
Doctor of Philosophy, The Ohio State University, 1970, Graduate School

Committee:

Not Provided (Other)

Subjects:

Mathematics

Keywords:

Triangulation;Geodesy;Nets

Mueller, Ivan IstvanThe gradients of gravity and their applications in geodesy /
Doctor of Philosophy, The Ohio State University, 1960, Graduate School

Committee:

Not Provided (Other)

Subjects:

Geology

Keywords:

Gravity;Geodesy

Sui, WeiguangCoral Paleo-geodesy: Inferring Local Uplift Histories from the Heights and Ages of Coral Terraces
Master of Science, The Ohio State University, 2011, Geological Sciences
Coral grows in a limited depth range, and therefore flights of coral terraces frequently observed in tropical island arcs manifest the uplift of the earth's crust relative to sea level. The fundamental problem in interpreting such markers of relative sea level change is that relative sea level change is affected by changes in land or sea level. If we know the present-day height and the age of each coral terrace, the depth at which the coral originally grew and the history of absolute sea level in that region, then it is a simple matter to infer the vertical uplift history of the crust on which the terraces were constructed. There are uncertainties in each of these quantities, and therefore any such interpretation has to be made on a statistical or probabilistic basis. We assume that the errors in the measurement of terrace height and the age of the terrace are negligible compared to the uncertainties in coral growth depth and paleosea level. A preliminary estimate of crustal uplift history can be made using a standard least squares approach. Because the probability density function (PDF) for coral growth depth is highly asymmetrical, any technique that is based on the assumption of Gaussian or normal depth distributions is not well suited to this problem. In principle, it is possible to estimate a PDF for coral growth depth based on the specific assemblages of coral species comprising each terrace. We assume that such PDFs are available, and that it is also possible to assign a standard error to the sea level curve at each individual epoch, and show that it is possible to estimate the crustal uplift history using a maximum likelihood approach. This approach, if carried out at large numbers of tropical islands in a single tectonically active region, can also provide a basis for revising the sea level history models already developed for that region.

Committee:

Michael Bevis (Advisor); C. K. Shum (Committee Member)

Keywords:

Paleosea level; coral growth; vertical movement; paleo-geodesy; maximum likelihood

Bossler, John DavidBayesian inference in geodesy /
Doctor of Philosophy, The Ohio State University, 1972, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Geodesy;Bayesian statistical decision theory

Sprinsky, William HaroldThe design of special purpose horizontal geodetic control networks /
Doctor of Philosophy, The Ohio State University, 1975, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Geodesy

Raleigh, David BaringStraight Skeleton Survey Adjustment Of Road Centerlines From Gps Coarse Acquisition Data: A Case Study In Bolivia
Master of Science, The Ohio State University, 2008, Geodetic Science and Surveying
Bolivia is the test subject for the Third World Mapping Project, a non-profit group at The Ohio State University created to aid countries with their mapping infrastructure. Bolivia’s Military Geograpic Institute (IGM) has limited resources for mapping rural roads and has enlisted the help of The Ohio State University’s Geodesy and Geodynamics Group to begin the process of updating their nation’s roadmaps. The planned project will use inexpensive GPS receivers, automated data archiving and semi-automated adjustment of data. This combination of receivers and semi-automated adjustment should help IGM produce high quality roadmaps with a relatively small investment. The focus for this thesis is the creation of the semi-automated adjustment tools and the role of topology in this data averaging scheme. In an effort to offset the poor data quality of handheld GPS receivers the Topology Adjustment Cartography Kit (TACK) will average repeated surveys of roads using a polygon skeletonization called the straight skeleton (Aichholzer et al., 1995).

Committee:

Michael Bevis, PhD (Advisor); Alan Saalfeld, PhD (Committee Member)

Subjects:

Geography

Keywords:

geodesy; gps; coarse acquisition; straight skeleton

Dermanis, AthanasiosProbabilistic and deterministic aspects of linear estimation in geodesy /
Doctor of Philosophy, The Ohio State University, 1976, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Length measurement;Geodesy

Blaha, GeorgesInvestigations of critical configurations for fundamental range networks /
Doctor of Philosophy, The Ohio State University, 1971, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Geodesy;Geodetic satellites

Sharni, DanEarth gravity models based on distinct 5? by 5? values of topography and moho /
Doctor of Philosophy, The Ohio State University, 1966, Graduate School

Committee:

Not Provided (Other)

Subjects:

Geophysics

Keywords:

Gravity;Geodesy

Holtkamp, Stephen GreggNEW METHODS FOR DETECTING EARTHQUAKE SWARMS AND TRANSIENT MOTION TO CHARACTERIZE HOW FAULTS SLIP
Doctor of Philosophy, Miami University, 2013, Geology & Environmental Earth Science
The possibility for earthquakes to be triggered by or related to each other or an external “aseismic” factor impacts hazard assessment and mitigation. With this dissertation, we have worked towards improvement of observation and modeling for earthquake swarms, slow slip associated with episodic tremor and slip, and human induced seismicity. Each of these cases has the potential to influence when, where, and to what size an earthquake can grow. First, we produce geodetic inversions of slow slip events in Cascadia, and highlight two unique instances where slow slip and non-volcanic tremor are not spatially correlated. In Cascadia, the correlation is so strong that tremor has become an accepted proxy for slow slip, but we show that this is not always the case. We show that the depth of the tremor may resolve this discrepancy. Second, we conduct a search for earthquake swarms along major convergent margins and find 180 swarms occurring within the seismogenic megathrust. We find evidence that these swarms are driven by aseismic slip, and may be broadly anti-correlated with large, destructive megathrust events. Third, we investigate this apparent anti-correlation with large megathrust events in detail by examining all Mw>7.5 earthquakes and classify them based on their relationship to swarm-generating regions of the interface. We find that large earthquakes are five times more likely to terminate in swarm regions than they are to propagate through swarm regions, suggesting that swarm regions are delineating where megathrusts are segmented. Lastly, we develop a multiple station waveform cross-correlation technique to investigate local to regional seismic data which is able to detect earthquakes several orders of magnitude smaller than traditional techniques. We use this technique to create a ~20 fold increase in detected seismicity during the 2011 Youngstown, Ohio earthquake sequence, allowing us to go well beyond the standard “proximity test” and conclusively establish a causal relation between wastewater injection and earthquakes. In total, we expect this dissertation to improve our understanding of how these unique seismic sequences occur, what their underlying mechanism is, and how they may be related to the damaging earthquakes sought out by the hazard assessment community.

Committee:

Michael Brudzinski, PhD (Advisor); Brian Currie, PhD (Committee Member); Elizabeth Widom, PhD (Committee Member); Jonathan Levy, PhD (Committee Member); Zhigang Peng, PhD (Committee Member); Michael Pechan, PhD (Committee Member)

Subjects:

Geophysics

Keywords:

Seismology; Geodesy; Geophysics; Earthquake Swarms; Aseismic Slip; Induced Seismicity; Triggered Seismicity; Subduction Zones

Archinal, Brent AllenDetermination of earth rotation by the combination of data from different space geodetic systems /
Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Earth;Geodesy

Cushman, Solomon FrederickThe Ohio Standard Baseline, 1970.9.
Doctor of Philosophy, The Ohio State University, 1972, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Base measuring;Geodesy

Obenson, Gabriel Francis TambeDirect evaluation of the earth's gravity anomaly field from orbital analysis of artificial earth satellites /
Doctor of Philosophy, The Ohio State University, 1970, Graduate School

Committee:

Not Provided (Other)

Subjects:

Geophysics

Keywords:

Gravity anomalies;Gravity;Artificial satellites;Satellite geodesy

Vazquez Becerra, Guadalupe EstebanGEODESY IN ANTARCTICA: A PILOT STUDY BASED ON THE TAMDEF GPS NETWORK, VICTORIA LAND, ANTARCTICA
Doctor of Philosophy, The Ohio State University, 2009, Geodetic Science and Surveying
The objective of the research presented in this dissertation is a combination of practical and theoretical problems to investigate unique aspects of GPS (Global Positioning System) geodesy in Antarctica. This is derived from a complete analysis of a GPS network called TAMDEF (Trans Antarctic Mountains Deformation), located in Victoria Land, Antarctica. In order to permit access to the International Terrestrial Reference Frame (ITRF), the McMurdo (MCM4) IGS (The International GNSS Service for Geodynamics, formerly the International GPS Service) site was adopted as part of the TAMDEF network. The following scientific achievements obtained from the cited analysis will be discussed as follows: (1) The GPS data processing for the TAMDEF network relied on the PAGES (Program for Adjustment of GPS Ephemerides) software that uses the double-differenced iono-free linear combination, which helps removing a big partial of bias (mm level) in the final positioning. (2) To validate the use of different antenna types in TAMDEF, an antenna testing experiment was conducted using the National Geodetic Survey (NGS) antenna calibration data, appropriate for each antenna type. Sub-daily and daily results from the antenna testing are at the sub-millimeter level, based on the fact that 24-hour solutions were used to average any possible bias. (3) A potential contributor that might have an impact on the TAMDEF stations positioning is the pseudorange multipath effect; thus, the root mean squared variations were estimated and analyzed in order to identify the most and least affected sites. MCM4 was found to be the site with highest multipath, and this is not good at all, since MCM4 is the primary ITRF access point for this part of Antarctica. Additionally, results from the pseudorange multipath can be used for further data cleaning to improve positioning results. (4) The Ocean Tide Modeling relied on the use of two models: CATS02.01 (Circum Antarctic Tidal Simulation) and TPXO6.2 (TOPEX/Poseidon) to investigate which model suits the Antarctic conditions best and its effect on the vertical coordinate component at the TAMDEF sites. (5) The scatter for the time-series results of the coordinate components for the TAMDEF sites are smaller when processed with respect to the Antarctic tectonic plate (Case I), in comparison with the other tectonic plates outside Antarctica (Case II-IV). Also, the seasonal effect due to the time-series seen in the TAMDEF sites with longer data span are site dependent; thus, data processing is not the reason for these effects. (6) Furthermore, the results coming from a homogeneous global network with coordinates referred and transformed to the ITRF2000 at epoch 2005.5 reflect the quality of the solution, obtained when processing TAMDEF network data with respect to the Antarctic tectonic plate. (7) An optimal data reduction strategy was developed, based on three different troposphere models and mapping functions, tested and used to estimate the total wet zenith delay (TWZD) which later was transformed to precipitable water vapor (PWV). PWV was estimated from GPS measurements and validated with a numerical weather model, AMPS (Antarctic Mesoscale Prediction System) and radiosonde PWV. Additionally, to validate the TWZD estimates at the MCM4 site before their conversion into the GPS PWV, these estimates were directly compared to TWZD computed by the CDDIS (Crustal Dynamics Data Information System) analysis center. (8) The results from the Least-Squares adjustment with Stochastic Constraints (SCLESS) as performed with PAGES are very comparable (mm-level) to those obtained from the alternative adjustment approaches: MINOLESS (Minimum-Norm Least-Squares adjustment); Partial-MINOLESS (Partial Minimum-Norm Least-Squares adjustment), and BLIMPBE (Best Linear Minimum Partial-Bias Estimation). Based on the applied network adjustment models within the Antarctic tectonic plate (Case I), it can be demonstrated that the GPS data used are clean of bias after proper care has been taken of ionosphere, troposphere, multipath, and some other sources that affect GPS positioning. Overall, it can be concluded that no suspected of bias was present in the obtained results, thus, GPS is indeed capable of capturing the signal which can be used for further geophysical interpretation within Antarctica.

Committee:

DOROTA A. GREJNER-BRZEZINSKA, PhD (Advisor); BURKHARD SCHAFFRIN, PhD (Committee Member); TERRY WILSON, PhD (Committee Member)

Subjects:

Geology; Geophysics

Keywords:

GPS; GEODESY; ANTARCTICA; TAMDEF

Willis, Michael J.Crustal motion in the Antarctic interior from a decade of global positioning system measurements
Doctor of Philosophy, The Ohio State University, 2008, Geological Sciences

A decade of Global Positioning System (GPS) data have been collected at bedrock sites in southern Victoria Land, Antarctica. Measured motions of the crust have been examined to determine if ongoing tectonic deformation occurs within the study area, across the structural boundary between East and West Antarctica. Crustal motions are used to test for activity over the offshore Terror Rift, where young faulting is documented, and to asses locally whether the active Erebus volcano deforms the crust. Bedrock motions caused by large scale ice-mass changes that have occurred in the area since the Last Glacial Maximum are also a major focus of the study.

The horizontal GPS motions record Antarctic plate motion of ~15 mm/yr to the southeast. No deformation is observed over the Transantarctic Mountains Front Zone. Very small amounts of deformation are observed along the Terror Rift, however the recorded direction of motions may be the result of Glacial Isostatic Adjustment (GIA), rather than active tectonics. Recorded motions observed to the south of Ross Island suggest that the Terror Rift continues beneath the Ross Ice Shelf. No volcanic loading signal is observed.

Vertical crustal motions exhibit a down-to-the-east tilt over the study area. A suite of earth models, including more than three hundred different mantle viscosity profiles, three different lithospheric thicknesses and three different ice histories, were used to model uplift due to Glacial Isostatic Adjustment driven by ice mass change. None replicate the observed tilt. Two Relative Sea Level curves for the region also could not be replicated by GIA models examined. Comparison of GPS vertical velocities and our GIA models produce well-constrained earth models for the study area, but suggest that current ice history models for the region must be revised to replicate measured crustal motions.

We compare the output of our GPS-constrained models with published crustal uplift rates used in modern ice mass balance estimates from the Gravity Recovery and Climate Experiment (GRACE) satellite mission. Application of our model, with a factor of two weaker West Antarctic mantle, increases the apparent ice mass loss from West Antarctica by about 50%.

Committee:

Terry Wilson (Advisor)

Keywords:

Antarctica; post glacial rebound; glacial isostatic adjustment; GIA; PGR; GPS; tectonics; geodesy; southern Victoria Land

Baek, Sang-HoDEM generation and ocean tide modeling over Sulzberger Ice Shelf, West Antarctica, using synthetic aperture radar interferometry
Doctor of Philosophy, The Ohio State University, 2006, Geodetic Science and Surveying
Accurate knowledge of the Antarctic ice sheet mass balance plays an important role on the global sea level change. Ocean tides (barotropic and baroclinic) and tidal currents cause basal melting and migration of grounding lines, which are all critical to the accurate determination of ice sheet or ice stream mass balance. Ocean tides in the Antarctic Ocean, especially underneath ice shelves or sea ice, are poorly known primarily due to lack of observations with adequate resolution and knowledge of the bathymetry and ice shelf bottom roughness. InSAR has been used to measure the ice sheet mass balance, ice topography, ice stream velocity, and the location of the grounding lines. To properly use InSAR measurements for ice mass balance and because of their high spatial resolution (tens of meters), knowledge of ocean tides underneath the ice shelves needs to be accurately known and with commensurate resolution. Here two-pass differential InSAR (DInSAR) technique is applied for tidal signal modeling underneath the Sulzberger ice shelf, West Antarctica. The fine resolution (60-m) Digital Elevation Model (DEM) over grounded ice and ice shelf, obtained by combining ERS-1/2 tandem InSAR and ICESat laser altimetry, has been used to correct the topography phase from interferograms, resulting in a more accurate time series of vertical deformation measurements. In this study, it is demonstrated for the first time, that observable tidal constituents can be estimated underneath an ice shelf using an InSAR time series. In particular, it is shown that the time series of observed tidal differences from InSAR agrees well with a number of global/regional ocean tide models such as NAO.99b, TPXO.6.2, GOT00.2, CATS02.01, and FES2004, with the regional model, CATS02.01, having the best agreement. The technique developed here can be applied to other ice shelf regions where tide modeling is poor in accuracy and resolution.

Committee:

C. K. Shum (Advisor)

Keywords:

SAR; Synthetic Aperture Radar; InSAR; Digital Elevation Model; Tide modelling; ICESat; Altimetery; Space geodesy; Antarctica; Ice shelf

Stukhart, GeorgeThe theory of geodetic observations /
Doctor of Philosophy, The Ohio State University, 1968, Graduate School

Committee:

Not Provided (Other)

Subjects:

Geophysics

Keywords:

Geodesy

Ritzer, Jason AndreasThe Topography, Gravity, and Tectonics of the Terrestrial Planets
Doctor of Philosophy, Case Western Reserve University, 2010, Geological Sciences
The topography and gravity of some of the solid earth bodies in our solar system including the Moon, Mercury, and Mars are used to investigate the density structure, lithospheric structure and resultant tectonic deformation. The difficulties in representing the gravitational field based on satellite data are explored including possible solutions including a change of representational basis function. The problem of representing the gravitational field based on non-uniform data distributions is addressed. Early results and expected returns from the MESSENGER mission to Mercury including compressional tectonics are studied.

Committee:

Steven Hauck, II (Committee Chair); James Van Orman (Committee Member); J. Iwan D. Alexander (Committee Member); Ralph Harvey (Committee Member)

Subjects:

Geophysics; Mathematics

Keywords:

Geophysics; Planetary Science; Geodesy; Lithosphere; Gravity; Topography; Mars; Mercury; Spherical Harmonics; Radial Basis

Cothren, Jackson DReliability in constrained Gauss-Markov models: an analytical and differential approach with applications in photogrammetry
Doctor of Philosophy, The Ohio State University, 2004, Geodetic Science and Surveying
Reliability analysis explains the contribution of each observation in an estimation model to the overall redundancy of the model, taking into account the geometry of the network as well as the precision of the observations themselves. It is principally used to design networks resistant to outliers in the observations by making the outliers more detectible using standard statistical tests.It has been studied extensively, and principally, in Gauss-Markov models. We show how the same analysis may be extended to various constrained Gauss-Markov models and present preliminary work for its use in unconstrained Gauss-Helmert models. In particular, we analyze the prominent reliability matrix of the constrained model to separate the contribution of the constraints to the redundancy of the observations from the observations themselves. In addition, we make extensive use of matrix differential calculus to find the Jacobian of the reliability matrix with respect to the parameters that define the network through both the original design and constraint matrices. The resulting Jacobian matrix reveals the sensitivity of reliability matrix elements highlighting weak areas in the network where changes in observations may result in unreliable observations. We apply the analytical framework to photogrammetric networks in which exterior orientation parameters are directly observed by GPS/INS systems. Tie-point observations provide some redundancy and even a few collinear tie-point and tie-point distance constraints improve the reliability of these direct observations by as much as 33%. Using the same theory we compare networks in which tie-points are observed on multiple images (n-fold points) and tie-points are observed in photo pairs only (two-fold points). Apparently, the use of two-fold tie-points does not significantly degrade the reliability of the direct exterior observation observations. Coplanarity constraints added to the common two-fold points do not add significantly to the reliability of the direct exterior orientation observations. The differential calculus results may also be used to provide a new measure of redundancy number stability in networks. We show that a typical photogrammetric network with n-fold tie-points was less stable with respect to at least some tie-point movement than an equivalent network with n-fold tie-points decomposed into many two-fold tie-points.

Committee:

Burkhard Schaffrin (Advisor)

Subjects:

Engineering, Civil; Geodesy

Keywords:

photogrammetry; geodesy; least squares; network design; Gauss-Markov model; Gauss-Helmert model

Cruz, Jaime Y.Disturbance vector in space from surface gravity anomalies using complementary models /
Doctor of Philosophy, The Ohio State University, 1985, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Gravity anomalies;Geodesy

Hannah, JohnThe development of comprehensive error models and network adjustment techniques for inertial surveys.
Doctor of Philosophy, The Ohio State University, 1981, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Surveying;Geodesy

Katsambalos, Kostas E.Simulation studies on the computation of the gravity vector in space from surface data considering the topography of the earth /
Doctor of Philosophy, The Ohio State University, 1981, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Gravity;Geodesy;Boundary value problems

Uotila, Urho A.Investigations on the gravity field and shape of the earth /
Doctor of Philosophy, The Ohio State University, 1960, Graduate School

Committee:

Not Provided (Other)

Subjects:

Geology

Keywords:

Gravity;Geodesy;Earth ;Gravity anomalies

Badekas, JohnEstablishment of an ideal world geodetic system /
Doctor of Philosophy, The Ohio State University, 1969, Graduate School

Committee:

Not Provided (Other)

Subjects:

Geology

Keywords:

Geodesy

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