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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.
71

On the dynamics of buoyant fluid injected into a confined aquifer

Gunn, I. January 2011 (has links)
This thesis is concerned with examining the dynamics of CO<sub>2</sub> injected into a porous layer. Solutions are found for flows corresponding to various different faulting and background flow scenarios for a confined inclined porous layer. The speed of advance and shape of the injected fluid front are calculated. It is found that different boundary conditions associated with different faulting scenarios can lead to very different spatial distributions of CO<sub>2</sub>. Investigation is made into how a confined layer may begin to fill with injected fluid when the injected current approaches a fault. The different solutions for different faulting scenarios can indicate radically contrasting injection strategies. Some possible consequences of a mixing reaction in a porous layer are also addressed. The understanding gained from the solutions found may help in the interpretation of remote geophysical observations and so contribute to the assessment of safety and the optimisation of injection strategies for carbon dioxide sequestration scenarios.
72

Atmosphere electricity : some observations near the ground

Adkins, C. J. January 1958 (has links)
No description available.
73

An investigation of some properties of the ionosphere by means of a rapid frequency-change experiment

Briggs, B. H. January 1952 (has links)
No description available.
74

Seismic wave diffraction theory

Chapman, C. H. January 1970 (has links)
No description available.
75

Coalescence microseismic mapping : an imaging method for the detection and location of seismic events

Drew, J. January 2010 (has links)
The Coalescence Microseismic Mapping method I have developed is applicable to event detection and location for a sparse array, while still benefiting from rigorous statistical analysis by averaging data over the array. Formulated within a Bayesian framework with respect to traveltime, the automated method simultaneously identifies and quantitatively images source location, by mapping a scalar signal that characterizes both the presence and timing of a seismic arrival. Unlike traveltime inversion, the numerical approach is not restrictive in regards to the type and distribution of errors. Effectively providing the probability density functions, the approach also allows for new ways to aggregate, visualize and interpret the results. Signal phase information can be assimilated in the solution when this can be recovered from the data, with the potential for improving location resolution. The method can be incorporated within a general integrated workflow, including an iterative or global inversion for multiple parameters. The theory is discussed in detail then applied to two datasets. The first is the integrated analysis of data acquired by a surface array deployed in the vicinity of Askja Volcano, Iceland. Here the signal phase information is recovered after correction for shear wave splitting and compensation for attenuation and station response. The second is for data acquired by a sub-surface array, monitoring seismic activity associated with hydraulic fracturing of a hydrocarbon reservoir. In this example the location is further constrained by including weighted signal polarization information in the search.
76

Measurement of gravity at sea

Beaumont, J. O. January 1965 (has links)
No description available.
77

Phase integral calculations of ionospheric reflections

Cooper, E. A. January 1963 (has links)
No description available.
78

Magnetic anisotropy of rocks

Fuller, M. D. January 1962 (has links)
No description available.
79

The secular variations of the earth's magnetic field

Allan, D. W. January 1962 (has links)
No description available.
80

The electrical conductivity of the earth's interior

Hughes, H. January 1954 (has links)
No description available.

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