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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.
121

Investigation of applying normal mode initialization method to planetary stationary wave disturbances

Niu, Yang January 1992 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1992. / Includes bibliographical references (leaves 68-70). / by Yang Niu. / M.S.
122

The effect of evaporation of frontogenesis

Huang, Ho-Chun January 1989 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1989. / Title as it appears in the M.I.T. Graduate List, Sept. 1989: The effect of rain evaporation of frontogenesis. / Includes bibliographical references (leaves 38-40). / by Ho-Chun Huang. / M.S.
123

Processing of randomly obtained seismic data / Processing of randomly acquired seismic data

Sun, Youshun, 1970- January 1998 (has links)
Thesis (S.M. in Geosystems)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1998. / Includes bibliographical references (leaves 62-64). / by Youshun Sun. / S.M.in Geosystems
124

Planktonic foraminifera in the sea of Okhotsk : population and stable isotopic analysis from a sediment trap

Alderman, Susan Elizabeth January 1996 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1996. / Includes bibliographical references (leaves 46-53). / by Susan Elizabeth Alderman. / M.S.
125

Evaluating changes in strontium chemistry of stream water in response to environmental stress

Hall, Tavenner Marie January 1995 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1995. / Includes bibliographical references (leaves 47-49). / by Tavenner Marie Hall. / M.S.
126

The morphology and dynamics of subducting lithosphere

Fischer, Karen Marie January 1989 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1989. / Vita. / Includes bibliographical references (leaves 175-189). / by Karen Marie Fischer. / Ph.D.
127

The dynamic role of ridges in a β-plane channel : towards understanding the dynamics of large scale circulation in the Southern Ocean

Wang, Liping January 1993 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1993. / Includes bibliographical references (leaves 246-251). / by Liping Wang. / Ph.D.
128

The transient response of bedrock river networks to sudden base level fall

Crosby, Benjamin T. (Benjamin Thomas) January 2006 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2006. / Includes bibliographical references. / Following a change in the factors that determine landscape form, a transient signal of adjustment propagates through the river network, progressively adjusting channels and hillslopes to the new conditions. When conditions favor incision, the rate and mechanism by which this signal propagates throughout the network determines basin response time. This ultimately influences the growth and stability of mountain ranges and the tempo of sediment delivery to depositional basins. As this incision signal propagates through the river network, its upstream extent is often recognized as a discrete, steep convexity in the channel profile, defined here as a knickpoint. In this thesis, theoretical, numerical, and field-based research techniques are utilized to study the initiation and distribution of knickpoints within fluvial networks. Field observations are derived from the Waipaoa River on the North Island of New Zealand. In the Waipaoa, 236 knickpoints distributed throughout the network define the upstream extent of a large magnitude incision signal initiated -18,000 years ago. These features, frequently located at the confluence between small drainage area tributaries and trunk-streams, are characterized as near-vertical single or multi-step waterfalls. / (cont.) Though flights of trunk-stream strath terraces document a prolonged incision history, the single step knickpoints upstream of tributary junctions suggest that trunk-stream incision can outpace tributary response, producing fluvial hanging valleys. Variations in knickpoint form observed in non-hanging tributaries demonstrate that many factors, both internal and external to the tributary, ultimately determine knickpoint form. We use a two dimensional numerical landscape evolution model (CHILD) to test a suite of bedrock channel incision rules to determine whether instantaneous or prolonged base level fall can trigger erosion thresholds. These experiments reveal that for bedrock channel incision rules where the relationship between slope and erosion rate is not positive and monotonic, incision rate can decrease with increasing slope until the incision rate is less than the background uplift rate. This provides a mechanism for hanging valley formation when over-steepened tributaries cannot incise at rates equal to the incision in the mainstem. This suggests that if trunk-stream incision outpaces tributary response, hanging valleys form, thus limiting the upstream propagation of incision signals and ultimately increasing basin response time. / by Benjamin T. Crosby. / Ph.D.
129

The use of Hf-isotopes and high field strength elements to constrain magmatic processes and magma sources

Salters, Vincent J. M January 1989 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1989. / Includes bibliographical references. / by Vincentius Johannes Maria Salters. / Ph.D.
130

Recent lunar magnetism

Buz, Jennifer January 2011 (has links)
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2011. / Cataloged from PDF version of thesis. Page 37 blank. / Includes bibliographical references (p. 36). / The magnetization of young lunar samples (<1.5 Ga) is a mystery because common sources of magnetic fields (e.g. core dynamo and long-lived impact plasma fields) have not been present within the last 1.5 Ga. To better characterize the source of magnetization in young lunar samples, we conducted paleomagnetic measurements on several subsamples of lunar glass 12017, which has a formation age of -9 ka, as well as on the underlying basalt from the same sample. Various methods of magnetization were tested, including possible contamination from Earth's magnetic field, exposure to transient magnetic fields such as on the Apollo module, and interaction fields from underlying magnetized rocks. The magnetic field emanated by the rock underlying the 12017 glass was determined to be -150 nT, comparable with the noise associated with paleomagnetic techniques. This opens up a new possible source of magnetization for samples- the laboratory. It is likely that other young lunar samples' paleointensities are overestimates, and that the strengths of magnetic fields on the Moon in the last 1.5 Ga are more similar to the strengths we observed from the 12017 glass. Underlying rocks and laboratory techniques are viable sources of magnetic fields, therefore, young lunar sample magnetization can no longer be used as evidence against an ancient core dynamo. Furthermore, the basalt portion of the 12017 is unidirectionally magnetized, suggesting an ancient core dynamo on the Moon when it formed at 3.2 Ga. / by Jennifer Buz. / S.M.

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