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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

An integrated seismic and well log analysis for the estimation of reservoir properties

Saggaf, Muhammad M January 2000 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2000. / Includes bibliographical references (p. 391-399). / We present an integrated approach for characterizing the reservoir and estimating its properties both at the well locations and in the inter-wen regions. Such an approach can be an invaluable tool for attaining a detailed, consistent, and complete characterization of the reservoir, as not only does it incorporate all major sources of information that shape our understanding of the reservoir, including core descriptions, well Jogs, seismic data, and a priori knowledge of the geological setting of the region, but also it develops means for utilizing these sources of information in a unified manner that gives rise to a coherent framework for relating these sources of information to yield an integrated reservoir model. We analyze the different components of this approach, develop methodologies for improving the prediction accuracy of each, and link the mechanisms across these components to achieve an accurate and consistent characterization of the reservoir. The issues we tackle in this thesis can be broadly divided into four categories: enhancement of the seismic resolution, estimation of the reservoir properties at the well locations, characterizing the reservoir in the inter-well regions, and pre-processing the data to remedy any incompleteness or inconsistency. / by Muhammad M. Saggaf. / Ph.D.
372

Dependence of continental severe convective instability on climatological environmental conditions

Agard, John Vincent January 2017 (has links)
Thesis: Ph. D. in Atmospheric Science, Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2017. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 115-119). / Most of Earth's strongest atmospheric convection occurs over the continents, where potential energy is stored over time in metastable vertical profiles, only to be released rapidly by severe storms. In contrast to equilibrium-state convection in tropical ocean regions, there is a relative paucity of research exploring the climate dynamics of continental deep convection. This work makes a contribution to rectifying that deficiency by exploring the physical mechanisms by which convective available potential energy (CAPE) is generated, and their dependence on climatological properties of the Earth's environment. First, a budget of the time tendency of CAPE is used to examine the buildup of CAPE in advance of severe convective storm events in North America via case studies using reanalysis data. Contributions to extreme peak CAPE from relative advection of air masses, diabatic heating of the surface boundary layer, and radiative cooling of the free troposphere are computed. In all 8 cases studied, CAPE buildup is found to be driven primarily by fluxes of heat and moisture from the surface into the boundary layer on sub-diurnal time scales, and not by radiative cooling or the relative advection of air masses at low and upper levels over multiple days. This result is then further explored using an idealized two-dimensional continental framework using a minimal numerical model. Experiments in both 2-column and 40- column configurations demonstrate a link between discontinuities in surface moisture and high levels of transient CAPE. Surface entropy flux is once again found to be the primary driver of peak CAPE buildup within the model. Finally, a thermodynamic constraint on CAPE in continental environments is established using an idealized, one-dimensional model. This theoretical model incorporates the physical principle of CAPE generation identified using reanalysis and two-dimensional modeling by considering a dry adiabatic column that comes into contact with a moist land surface. A system of equations is derived to describe the evolution of the ensuing surface boundary layer. From these, the maximum value of transient CAPE in the column can be found for any particular combination of surface temperature and moisture. It is demonstrated that, for a given range of surface temperatures, the value of peak CAPE scales with the Clausius-Clapeyron relation. / by John Vincent Agard. / Ph. D. in Atmospheric Science
373

The slow manifold and the persisting gravity waves

Krishnamurthy, Venkataramanaiah January 1985 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1985. / Microfiche copy available in Archives and Science. / Bibliography: leaves 144-146. / by Venkataramanaiah Krishnamurthy. / Ph.D.
374

Seismological applications of boundary integral and Gaussian beam methods

Benites Calderón, Rafael January 1991 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1991. / Includes bibliographical references (p. 215-221). / by Rafael Benites Calderón. / Ph.D.
375

The Day Nui Con Voi mylonitic belt in Southwestern China and Its implications for the early Cenozoic extrusion of Indochina

Swanson, Erika M January 2007 (has links)
Thesis: S.B., Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2007. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 42-43). / The early Cenozoic India-Asia collision resulted in the extrusion of large crustal fragments southeast from the Eastern Himalayan syntaxis, with large shear zones at their boundaries that could have accommodated displacements of hundreds to perhaps a thousand kilometers. Along the northeastern edge of the Indochina extruded fragment, the belt of mylonitic metamorphic rocks generally referred to as the Ailao Shan/Red River shear zone forms the extrusion boundary. This shear zone actually consists of at least two belts, the Ailao Shan and the Day Nui Con Voi, which are separated by a narrow belt of unmetamorphosed Triassic sedimentary rocks. In the Chinese extension of the Day Nui Con Voi, the presence of sillimanite and garnet indicates the shear zone formed at amphibolite grade, and the mylonitic fabric defined by muscovite and biotite indicate left-lateral shearing. Ar/Ar cooling ages indicate the metamorphic rocks reached the cooling temperature of muscovite and biotite 26.07 ± 0.20 to 32.46 ± 0.25 Ma, ages that match those in the Day Nui Con Voi in north Vietnam. These data come from both the core orthogneiss of the shear zone as well as a narrow carapace of metasedimentary rocks of unknown age. Both rock units form an antiform in southern China that plunges below Triassic sedimentary rocks of South China. These relations show that: 1) the Day Nui Con Voi in China is the direct continuation of the same belt in north Vietnam, 2) the Day Nui Con Voi does not directly connect with the Ailao Shan shear zone, 3) the Day Nui Con Voi shear zone has a structural (?) cover of South China Mesozoic sedimentary rocks, 4) structural relations limit the amount of late stage left-lateral shear on the Indochina boundary, and 5) the structural relations require a more complex history for the shear zone along the NE boundary of the extruded Indochina crustal fragment than proposed by all earlier workers. / by Erika Swanson. / S.B.
376

An observational study of the austral spring statosphere : dynamics, ozone transport, and the "ozone dilution effect"

Atkinson, Roger John January 1993 (has links)
Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1993. / Includes bibliographical references (p. 367-385). / by Roger John Atkinson. / Sc.D.
377

Nonlinear ionospheric propagation effects on UHF and VLF radio signals

Groves, Keith Michael January 1991 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1991. / Includes bibliographical references (p. 179-184). / by Keith Michael Groves. / Ph.D.
378

Detection and characterization of in-situ fractures in the earth from vertical seismic profiling data

Cicerone, Robert D January 1991 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1991. / Includes bibliographical references (leaves 202-208). / by Robert D. Cicerone. / Ph.D.
379

Bed-load transport of mixed-size sediment

Wilcock, Peter R. (Peter Richard), 1953- January 1987 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmosphere and Planetary Sciences, 1987. / Vita. / Bibliography: leaves 196-199. / by Peter Richard Wilcock. / Ph.D.
380

A flume study of bed forms in a medium sand as a function of flow velocity

Goettel, Mary Jane W. (Mary Jane Westerwelt) January 1991 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1991. / Includes bibliographical references (v. 2, leaves 325-327). / by Mary Jane W. Goettel. / Ph.D.

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