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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.

Novel applications of airborne LiDAR and multispectral data for high-resolution geological mapping of vegetated ophiolitic rocks and sedimentary cover, Troodos Range, Cyprus

Grebby, Stephen Robert January 2011 (has links)
Practical and financial constraints associated with traditional field-based mapping are often responsible for the production of coarse-scale geological maps that lack detail and have inaccurately defined lithological contacts. Although remote sensing offers potential solutions to these constraints, conventional use of remotely sensed data is only effective when applied to barren terrain because just small amounts of vegetation cover can obscure or mask the underlying geological materials and structures. In this thesis, novel algorithms that utilise airborne Light Detection And Ranging (LiDAR) data and airborne multispectral imagery are applied to high-resolution geological mapping of vegetated ophiolitic rocks and sedimentary cover in the northern Troodos Range (Cyprus) with the aim of demonstrating their potential application to any geological setting. These novel algorithms involve quantification of geobotanical and topographical characteristics that are generally distinct for different lithological units, followed by automated image classification based upon these characteristics. Whilst the algorithms that individually exploit the geobotanical associations and the correlation between lithology and topography are capable of generating maps that are more detailed and have more accurately defined contacts than the existing geological maps of the study area, an integrated approach was found to significantly enhance the lithological mapping performance. Moreover, despite widespread vegetation cover, it is also shown that airborne LiDAR data and airborne multispectral imagery can be utilised to extract detailed and accurate structural information that is consistent with field-based data. Overall, the novel application of airborne spectral imagery and airborne LiDAR data has significant potential to aid accurate and high-resolution 1:5000-scale geological mapping over large areas of vegetated or non-vegetated terrain.

The analysis of seismic attenuation spectra in rock mass characterisation : a case study at Acklington opencast coal site

Young, R. P. January 1981 (has links)
No description available.

Seismic hazard assessment in Pakistan

Rehman, Khaista January 2010 (has links)
No description available.

The structural geology of an evaporite body

Tully, C. P. January 1983 (has links)
No description available.

Assessing the effect of mineral alteration on palaeointensities derived from volcanic rocks of cretaceous age

Davies, Ceri John January 2009 (has links)
No description available.

The influence of soil deposits on the seismic hazard

Belsham, Christopher Scott January 2011 (has links)
No description available.

Mineral-chemical lithostratigraphic relationships in biostratigraphically barren alluvial strata : a case study from the Skagerrak Formation Triassic (UKCS)

Chalton, B. I. January 2002 (has links)
The Triassic Skagerrak deposits of the Crawford Field, northern North Sea (UKCS), were deposited during semi-arid climatic conditions, within an active fault regime. The Triassic sequence represents fluvial alluvial sedimentation ranging from unconfined laterally extensive sheet flood deposits through to more confined small ribbon-like channel deposits. Geomorphologically stable areas demonstrate the development of palaeosols towards the upper regions of the Skagerrak Formation. Given the faunally barren nature and highly complex, fault-controlled sedimentation history, inter-well correlation of the Triassic interval of the field, has been relatively uncertain. The establishment of a well-constrained heavy mineralogical framework allowed a reservoir correlation scheme to be developed across eight of the ten wells present within the field. Sedimentological and petrophysical data were then integrated into this correlation scheme, to produce a high-resolution correlation across the Triassic interval of the field. The applicability of geochemistry to increase the resolution of the correlation scheme achieved across the Crawford Field Skagerrak Formation, was assessed through the analyses of samples on which, a detailed understanding of the heavy mineral assemblage and the sedimentology were known. Three distinct source terrains were identified for the Triassic interval of the Crawford Field. firstly, association 1 was sourced from a mid-Proterozoic hinterland, including the Western Gneiss Region (WGR) and the area to the south of this in Norway. This source terrain was, dominated by low-grade metasediments and higher-grade basic gneisses. Secondly, association 2 was sourced from a dominantly mid-Proterozoic hinterland containing subordinate Archaean and Caledonian age material, existing to the north around East Greenland. This source terrain was, dominated by high-grade metasediemtns and/or charnockites. Thirdly, association 3 was sourced from a mid-Proterozoic hinterland containing subordinate Caledonian age material and existed in the area around the WGR, Norway. This source terrain was, dominated by basic gneisses and rarer pyroxenites and peridotites.

The geology of Alangorssuaq, northern Nunarssuit Complex, South Greenland

Anderson, J. G. January 1975 (has links)
No description available.

An airborne remote sensing imaging spectrometry system applied to coastal water monitoring

Melo-Moreira, E. January 1998 (has links)
A remote sensing survey was conceived to assess the relevance and appropriateness of a low-costing imaging spectrometry system, <I>CASI</I> (Compact Airborne Spectrographic Imager) applied as an airborne tool for coastal water assessment of Loch Linnhe (Scotland, UK). The system is described and compared in detail with other conventional and operational remote sensing instruments based on published reports and general scientific literature. It became clear in the case of Loch Linnhe that an airborne platform is the only viable possibility for monitoring by remote sensing, due to both the low likelihood of cloud-free satellite data and the relatively small size of such a fiord system. A survey plan is proposed which accommodates the environmental, logistical and technological constraints deemed likely to emerge during the data acquisition period. This work encompassed the use of other ancillary instruments, namely two portable spectroradiometers (<I>SPECTRON SE-590</I>) and an airborne multispectral scanner (<I>DAEDALUS</I> 1268) to enable both the comparison and calibration in support of the main data source. The availability of <I>sea-truth</I> (collected for one week each month over a period of two months during 1991) was entirely the responsibility of the Scottish Office Agriculture and Fisheries Department (<I>SOAFD</I>) who generously made the data available to this project. Although this <I>in situ</I> data could not be gathered absolutely in concurrence with the survey flights, their careful use proved essential to the project. A methodology based on the tidal behaviour within the sea-loch is proposed, from which <I>sea-truth</I> is derived.

The geology of the Arnage district : a study of polymetamorphism

Farquhar, O. C. January 1951 (has links)
No description available.

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