Late Cainozoic environmental changes in Kashmir (33°30' to 34°30' N: 74°10' to 75°30' E) have been reconstructed using a range of techniques. The sedimentary record in Kashmir consists of a thick (>1000m) basin-fill sequence known as the Karewa group, together with glacial and related sediments in the surrounding mountain flanks. The Karewa sediments are fluviolacustrine in origin and comprise alternations of conglomerates, sands and clayey silts. Work on the lower Karewa formation, which has previously been dated palaeomagnetically to between 4 and 0.4 MaBP, involved the semi- quantitative analysis of clay-mineral assemblages by X-ray diffraction.The clay minerals in the lower Karewa mudstones are interpreted as detrital clays which reflect weathering within Kashmir basin. The analyses showed a change in clay mineralogy between about 2.5 and 2.3MaBP, from abundant kaolinite to abundant smectite. Work on the upper Karewa formation involved field description and mapping of facies, sedimentological analysis, dating using thermoluminescence (TL) and amino-acid racemization, and analysis of ostracod assemblages from lacustrine sediments. Areal restriction of the lake in Kashmir occurred about 0.4MaBP with the rapid uplift of the Pir Panjal Range. Sedimentological data show that aeolian dust formed a major input into the lake. Ostracod assemblages show that the lake itself was cool, shallow, alkaline and had abundant plant macrophytes, The lake drained between 120 and SOkaBP. Stratigraphical, sedimentological and faunal evidence suggests that this was a result of tectonically-induced drainage rather than climatically-induced desiccation. The glacial history of the surrounding mountain flanks was reconstructed by field mapping of glacial sediments and dated using TL and radiocarbon methods. Present and past patterns of glaciation wore assessed by the determination of equilibrium-line altitudes (ELAs), glaciation thresholds (GTs) and cirque aJtitudes. Glaciers extended to 2150 m a.s.l in the Great Himalayan flank and 2600 m a.s.l. in the Pir Panjal. There is evidence for only 2 pre-Holucene advances in Kashmir, the older of which predates 35kaBP. Present patterns of glacierization indicate a SW to NE rise in the height of ELAs and GTs suggesting topographic and precipitation control. An apparent reversal of trends during the past is explained by Quaternary uplift of the Pir Panjal Range.

The aim of work presented in this thesis was to explore the inter-relationships of cyclic sedimentation, relative sea-level change, and palaeoclimate as inferred from plant megafossils. To this end, the investigation focused on the classic plant-bearing Middle Jurassic succession of Yorkshire. The Middle Jurassic (Aalenian-Bathonian) Ravenscar Group of the Cleveland Basin (Yorkshire) comprises a predominantly fluvio-deltaic succession intercalated between thinner, laterally persistent marine units. There is a pronounced lateral facies change across the basin, from mainly alluvial sediments in the north to more marine deposits in the south. Although variable in character, the facies composing the sequence are described by four principal environments of deposition: alluvial, estuarine, lagoonal and marine. In an attempt to achieve a more accurate stratigraphic control on the succession, sequence-stratigraphic concepts are applied to outcrop exposures and subsurface cores. The identification of 'key surfaces' in the sequence resolves a series of lithological cycles which reflect relative sea-level fluctuations. Using this approach the Aalenian-Bathonian sequence can be subdivided into two large-scale (second-order) transgressive-regressive cycles onto which six medium-scale (thirdorder) cycles of transgression and regression are superimposed. The potential for correlating these lithological cycles regionally has been assessed by comparing coeval sections from southern Scandinavia. Plant-bearing fluvio-deltaic sequences from Bornholm and Scania were chosen as a means for appraising the lateral continuity of the cycles, and assessing what factors might have controlled their development. Study of floral remains from the Ravenscar Group within the context of this stratigraphic framework yields valuable palaeoclimatic information. Growth-ring analysis of fossil wood of Late Pliensbachian to Late Bathonian age indicates a distinctly seasonal climate with low to moderate interseasonal variation in tree growth. Significant intraseasonal influences on wood production are implicit in the abundance of false rings. Consideration of these results within a stratigraphic context suggests that conditions during the Bathonian were comparatively hostile: a finding which is interpreted to be due to more frequent and extended water shortages associated with a drier climate. These palaeoclimatic inferences are substantiated by evidence obtained from the examination of the flora using Correspondence Analysis (CA). This approach verifies the presence of a temporal fluctuation in the flora found by previous investigations and, furthermore, highlights physiognomic trends in the flora with time. The results from CA also indicate adverse growing conditions during the Bathonian, emphasized by the prevalence of xeromorphic taxa.

The Southern Uplands of Scotland is interpreted as a Lower Palaeozoic accretionary complex which formed on the northern margin of the Iapetus Ocean. Seven conglomerates which contain detritus derived from the north-west, from sources on the Laurentian continental margin, were studied. Granite clasts in five of the conglomerates have distinct petrographic and geochemical characteristics which indicate that separate source areas supplied detritus to the Southern Uplands at different times. The Llandeilo Corsewall Point and Caradoc Glen Afton conglomerates, which occur in Tracts 1 and 2 of the Northern Belt, contain granite clasts that yield similar Rb-Sr whole-rock isochron ages (c. 1,200 Ma, 600-660 Ma and c. 475 Ma) and similar Sm-Nd model ages. This suggests that the clasts in the two conglomerates were derived from related sources. Some of the granite clasts in the early Ashgill Shinnel Formation conglomerate, which occurs in Tract 3 of the Northern Belt, resemble those in the Corsewall Point conglomerate, but most are petrographically and geochemically distinct, and yield younger Sm-Nd model ages. The lower Llandovery Pinstane Hill conglomerate occurs in Tract 4 of the Central Belt, and contains granitic detritus which yields a Rb-Sr whole-rock isochron age of 458 ± 26 Ma and has similar characteristics to the clasts in the Shinnel Formation conglomerate. The granite clasts in the Corsewall Point and Glen Afton conglomerates are of a different age to the granite intrusions of northern Scotland, and are unlikely to have been derived from this region. Conglomerates in the Midland Valley contain granite clasts with different petrographic and isotopic characteristics to those supplied to the Southern Uplands during the Llandeilo and Caradoc. However, north-west Newfoundland has a similar igneous history to that recorded by the Southern Uplands clasts, which could be derived from this region. The clasts supplied to the Shinnel Formation and Pinstane Hill conglomerates during the Ashgill and Llandovery have more in common with the granitic detritus in the Midland Valley. Thus, the Southern Uplands form a distinct Caledonian terrane which was south-east of Newfoundland in the Llandeilo, and was affected by sinistral strike-slip displacements during and after accretion.

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Copies of author's previously published articles inserted. / Bibliography: leaves 194-208. / xviii, 208 leaves : ill., maps (chiefly col.), (some fold.), ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geology and Geophysics, 1998

Thesis (Ph. D. - Geosciences)--University of Arizona, 1985. / Includes bibliographical references (leaves 187-204).