• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 645
  • 538
  • 261
  • 3
  • 3
  • 1
  • Tagged with
  • 3126
  • 749
  • 261
  • 247
  • 247
  • 235
  • 131
  • 129
  • 122
  • 115
  • 114
  • 113
  • 110
  • 109
  • 101
  • 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.
61

Aspects of the palaeoecology of large predators, including man, during the British Upper Pleistocene, with particular emphisis on predator-prey relationships

Turner, Alan 1981 (has links)
This thesis discusses aspects of the palaeoecology of large predators, including man, during the Upper Pleistocene in Britain, with particular emphasis on predator-prey relationships. Upper Pleistocene is here taken as the Ipswichian (last) interglacial and the Devensian (last) glaciation. In addition to man, the term large predator includes lion, hyaena, wolf, leopard, bear, lynx and wolverine. The primary aim is to predict features of past predator and prey behaviour by integrating the results of modern ethological observations on similar or analogous species with the published evidence of Upper Pleistocene environments deduced from botanical, sedimentological and geomorphological investigations, and thus to extract information on trends in predator ecology and predator-prey relationships between the Ipswichian and Devensian. The study also examines the possibility that interpretations of human activity in Upper Pleistocene Britain have been founded largely on material accumulated by hyaenas, and discusses the value of examining past human behaviour from an ecological perspective in which man is regarded as one predator among many. The predictions of past behaviour are tested on vertebrate remains recovered from Upper Pleistocene deposits and how available in numerous museum collections. Much of the material derives from hyaena-accumulated bone assemblages in caves, and holds a potential wealth of information on the behaviour of this species and its predatory and scavenging activities. It is argued that the broad scope of the enquiry overcomes the shortcomings of this material which result from inadequate standards of recovery, recording and curation. The major conclusions reached in the study are: 1. That man and large mammals were seasonal occupants of Devensian Britain, on the evidence of reindeer antler remains, bear specimens in hyaena-accumulated assemblages and an analysis of tooth wear in horses. 2. That Ipswichian hyaenas found conditions more arduous than their Devensian counterparts, and may have died out at the end of Zone II of the interglacial, on the evidence of hyaena mortalities and the extent of bone consumption in hyaena-accumulated assemblages of the period. 3. That Devensian hyaenas did not tend to kill horses but instead scavenged their remains, most probably from lion kills, in view of the evidence for sexual parity in samples of horse teeth. 4. That much of the vertebrate material associated with Upper Palaeolithic industries and taken to show evidence of human economic activities is indeed the result of hyaena bone-accumulation, on the basis of comparisons with modern hyaena behaviour, and therefore inadmissable. 5. That an integration of present results with those from Europe and other parts of the world suggests that the importance of man as a member of the Pleistocene fauna may have been overemphasised.
62

The integration of laboratory data with flow simulation for application to seismic reservoir monitoring

Kirstetter, Olivier Hugues 2002 (has links)
No description available.
63

A sedimentological, diagenetic, and structural study in the middle tuffs, Borrowdale volcanics, English Lake District

Konig, Jacques Marcel 1964 (has links)
No description available.
64

The minor intrusions and structure of the Carlingford complex, Eire

Halsall, Trevor James 1974 (has links)
The Carlingford volcanic complex has an intense swarm of minor intrusions associated with it. Field work demonstrates that the swarm is composite, having involved the repeated injection of magma as dykes, cone sheets and complementary cone sheets in at least three rythmic cycles. Three major rock series are represented in these bodies: the tholeiitic basalt - craignurite series, the alkali basalt series and the high alumina basalt series, other rock types such as felsites, quartz feldspar porphyries and lamprophyres are present in minor proportions. Analysis of the structure of individual swarms suggests that basaltic magma was injected into the crust as an elongate ridge like body culminating in a cupola beneath the complex, from which cone sheet and radial dyke swarms emerged; linear dyke swarms arose from the ridge crest. Detailed geochemical investigations show, that the main magma series were derived by fractionation from basaltic parents; that two fractionation paths are represented in the alkali basalt series (the trachy basalt - tristanite series and hawaiite - mugearite - benmorite series); that craignurites represent a true fractionation product of tholeiitic magma and are petrochemically distinct from icelandites. Basalt fractionation at Carlingford was dominated by the separation of olivine and plagioclase at low pressure while the petrochemistry of the rocks suggests that the three parental stems - tholeiitic basaft, alkali basalt and high alumina basalt, were derived from a common parent by fractionation at higher pressure. Time relations indicate that common parent to be olivine tholeiite magma which it is suggested was formed at depths in excess of 60 km. Miscellaneous rock types, including felsites,lamprophyres and quartz feldspar porphyries are shown to have been derived by melting of crustal rocks during the injection of basic magma within the complex.
65

Real-time kinematic and fast static GPS measurements of ground deformation on Mount Etna, Sicily

Page, Delia 2000 (has links)
No description available.
66

Palaeomagnetic studies of Swedish varved sediments

Noel, Mark 1976 (has links)
No description available.
67

The geology of part of the province of Reggio-Calabria, Southern Italy

Sargent, G. E. G. 1979 (has links)
No description available.
68

Gravity monitoring of Mount Etna (Italy) through discrete and continuous measurements

Carbone, Daniele 2001 (has links)
No description available.
69

The palaeontology and stratigraphy of the liassic Rocks of Glamorgan

Wobber, F. J. 1963 (has links)
No description available.
70

The geology of the Vartdal area, Sunnmore, Norway and petrochemistry of the Sunnmore Eclogite Suite

Smith, D. C. 1976 (has links)
A reconnaissance geological study has been carried out in the Vartdal area of the basal gneiss region of S.W. Norway. The country rock is amphibolite facies gneiss of granodioritic composition affected by 4 folding phases, in part of Precambrian age. The gneiss contains pods of marble, amphibolite, metadolerite, anorthosite, diorite and eclogite. The chemical variation within the Sunnmore Metadolerite Suite is explained by igneous processes whilst the development of garnet- and biotite-rich corona assemblages is ascribed to autometamorphism rather than prograde regional metamorphism which caused amphibolitisation. The Sunnmore Eclogite Suite comprising 131 samples has been the subject of reconnaissance field and mineralogical studies and detailed petrographical and geochemical investigations. The field relationships provide clear evidence for a tectonic emplacement. 32 mineral types and 35 mineral reactions are recorded and a petrographic classification is proposed based on incompatibilities between certain minerals. 44 individual minerals have been analysed. Two distinct eclogite facies are recognised. 64 new whole-rock analyses for 13 major elements are presented. The suite shows a wide chemical variation but within certain orthopyroxene eclogite pods two types of trend can be identified, one best explained by high pressure igneous processes and the other by subsequent metamorphic differentiation. Estimates by chemical geothermometry and geobarometry suggest 800°C for the major eclogite re-equilibration at pressures up to 35kb. A review of the literature on experimental petrology indicates the feasibility of generating olivine-free eclogite from olivine-bearing mantle. Some possible tectonic models of eclogite genesis are discussed and an orogenic mixing process within a subduction zone emplacing mantle-derived eclogites into downwarped continental crust is favoured. Details of the chemical analytical techniques and of four computer programs specially developed for this project are described in appendices.

Page generated in 0.027 seconds