This study is based on palynological investigations at three sites in Java: Bandung Lake, Trinil and Bumiayu. At Bandung Lake (Holocene) three cores were studied, while surface section samples were studied from Trinil in East Java (Middle Pleistocene) and Bumiayu in Central Java (Upper Pliocene). The Trinil site is well known for its hominid fossils.The pollen flora at each site is fully described and illustrated while the pollen record at each location is used to reconstruct their vegetational, environmental and climatic histories. An attempt has also been made to determine whether palynology can be used to assist in dating these deposits. At all three sites, the character of the local vegetation is better reflected than that of the regional vegetation.One of the Bandung sites (Rancaekek) was radiocarbon dated, suggesting deposition between 11,000 and 7,000 yr BP and represents a freshwater lake deposits. The lake gradually shallowed toward 7,000 yr BP, at which time it was drained. The regional pollen component suggests climatic amelioration at about 8,000 yr BP, possibly reflecting the maximum incoming of solar radiation experienced in the Northern Hemisphere about 9,000 yr BP.Studies at Trinil revealed a mosaic of forest and open vegetation growing on a lahar. The former climate at this locality was probably markedly seasonal, not unlike that of the present day. Palynology conclusively demonstrates that this sequence is Pleistocene rather than Pliocene in age. The palynological record at Bumiayu reflects a regressive sequence with lagoonal and freshwater lacustrine environments (Kalibiuk Formation) followed by freshwater fluvial deposition (Kaliglagah Formation). The climate during the deposition of this sequence was markedly seasonal. The data support an Upper Pliocene age for the Bumiayu sequence.Three taxa are shown to have become extinct in Java during the Plio-Pleistocene. These are Stenochlaena lamrifolia and S. areolaris, which become extinct at the end of the Pliocene, and Daczydium, which is thought to have become extinct during the Holocene.

This study interprets the stratigraphic evolution of the mid-Cretaceous Urgonian Carbonate Platform sensu lato exposed in the northwestern Subalpine Chains of southeast France within a framework of dynamic environmental and climatic changes including relative sea-level fluctuations. Macroscopic observations of stratal geometries, especially stratal packaging within the succession revealed by differential weathering patterns have been integrated with the petrographic examination of limestone samples to assist in the interpretation of the carbonate succession. Seven hundred and twenty-eight rock samples were examined under the microscope as either thin sections or acetate peels and twenty five component parameters were used to define sediment composition within the data set. New and emerging analytical techniques have been used to interpret these data rather than the more traditional static fixed facies belts. Sequence stratigraphic concepts have been used to interpret platform evolution within the context of relative sea-level changes. In order to define microfacies and identify underlying environmental gradients computer optimized Jaccard's similarity coefficients matrices have been calculated between samples and component parameters using two computer programs SedUtil and JaccMat run on an IBM compatible Pentium personal computer. Computer optimized Jaccard's similarity coefficients similarity matrices are able to model both gradational and abrupt changes in facies composition in response to palaeogeographic and stratigraphic controls. Computer optimized similarity matrices between limestone compositional parameters from a series of logs show differences in the spatial and temporal nature of variations in sediment composition in response to environmental changes across the platform. The contrasts between the configurations of optimized similarity matrices are interpreted as indicating a palaeogeography at the beginning of the Urgonian characterised by a more strongly subsident basin to the southeast of the field area connected to the topographically-higher, tectonically more stable parts of the platform by low-angle slopes; the basin was eliminated by the end of the Urgonian. In addition optimized similarity matrices calculated between samples have been used to assist in defining eight-eight conventional microfacies assemblages which are described and illustrated using photomicrographs and pie-diagrams of modal composition. Despite the apparently conformable nature of the succession as observed in individual exposures, changes in the stratigraphy of the Urgonian platform sensu lata as traced along two southwest-northeast transects constructed through the Aravis and Bargy Chains indicate the existence of a low-angle distally steepened ramp topography at the top of the Hauterivian basement that sloped into a more strongly subsident basin. The Urgonian succession is divided into two third-order depositional sequences termed Depositional Sequence 1 and 2. In Depositional Sequence 1 all three systems tract are developed whereas Depositional Sequence 2 only contains transgressive and highstand systems tracts. The lowstand systems tract of Depositional Sequence 1 preserved in the southwest of the Aravis and Bargy Subalpine Chains is volumetrically significant, being dominated by hemipelagic deposits that shallow laterally to intertidal deposits to the northeast and also contain calciturbidites and two spectacular megabrecciahorizons. The two megabreccia horizons are interpreted as thin surficial collapse horizons formed by net extension on a very-low angle, previously kinematically stable slope, during fourth-fifth order relative sea-level falls. The lower sequence boundary of Depositional Sequence 1 passes laterally from being conformable in the southwest (deep-water basin) to being a major unconformity in the northeast ('inner' platform). However, this sequence boundary appears planar and concordantly bedded in the main and it is only in the northeastern Bargy Chain that it is observed as a erosional angular unconformity. The top of Depositional Sequence 1 is marked by the end of rudist lagoonal sediments and the deposition of beach facies which contain evidence of grain dissolution, overlain by Orbitolinidae foraminiferal rich horizons. By the top of Depositional Sequence 1 the low angle slope to the southwest had been totally subdued by sediment infilling and/or a decrease in the rate of differential subsidence. Depositional Sequence 1 was terminated by a comparatively minor relative sea-level fall followed by an immediate return to a major third-order relative sea-level rise and the basal transgressive deposits of Depositional 2. Depositional Sequence 2 re-establishes rudist sediment lagoonal deposition on the platform. It is often difficult to differentiate the transgressive and highstand systems tracts from one another in Depositional Sequence 2 and the boundary may be transitional. The upper sequence boundary of Depositional Sequence 2 is marked by a subaerial karst overlain by phosphatic greensands interpreted as reflecting a major relative sea-level fall and subsequent reflooding. Factors unique to carbonate depositional systems and their implications for the use of 'traditional' sequence stratigraphic models for carbonates are also discussed.

The project has involved the revision of the stratigraphy of the upper part of the Ordovician succession in central Portugal. Using evidence derived principally from the study of measured sections, with some limited geological mapping, this thesis first considers a new lithostratigraphy of the upper Ordovician deposits. The scheme presented includes four groups, twelve formations and eleven members. Most of the elements of the scheme are described here for the first time. The sedimentology of the deposits has been studied to allow an interpretation of the depositional environment. The history of sedimentation in the upper Ordovician is divided into three broad phases. In the first of these (phase A) storm-dominated deposition of detrital clastics took place on a wide, flat, shallow shelf. During the second phase (B) a localised area of igneous activity developed in the area of highest subsidence seen in the preceding phase. This igneous activity was accompanied by the deposition of some carbonate sediments. The third phase of deposition (C) is linked to the effects of the upper Ordovician glaciation. A review of most of the macrofauna recovered 1s given. The faunas of Portugal form a highly distinct and homogeneous "province" with those of Armorica, Spain, Sardinia. The palaeoecology of the faunas Montagne Noire and collected during this study are discussed. Thirteen broad associations (sensu Lockley 1983) are identified. Factors other than latitude-related influences play an important role in controlling the diversity, abundance and taxonomic constitution of the palaeocommunities. Twelve biozones are erected to cover the range of fossiliferous Ordovician strata examined in this project. The correlation between the biostratigraphie scheme erected herein and the international standard is discussed. An overview attempts to place the study area within the context of the peri-Gondwana shelf, and within the Variscan fold-belt.

No description available.

No description available.

The southern Arabian Gulf forms a wide shallow shelf, which slopes gently basinwards with no pronounced shelf edge. This has been a site of extensive carbonate deposition throughout the Quaternary. This PhD research project was undertaken in order to investigate the influence of Pleistocene glacioeustacy on sedimentation in the southern Arabian Gulf. In order to achieve this aim sediments were studied in core and outcrop from several sites in the southern Gulf region, and the sedimentary processes acting on the modern-day coastlines were investigated. Sea-floor sediments were studied in 20 engineering boreholes from 6 sites in the southern Arabian Gulf, penetrating to a maximum depth of 68.5 below present sea level. Seven depositional sequences are found within this interval, of which at least six are believed to have been deposited during the Pleistocene. It is most likely that the oldest of these date from oxygen isotope stage 11 (ca. 450ka) or earlier. These sequences are composed of a highly varied suite of sediments. Condensed sequences, omissions and expanded sections are common within the Arabian Gulf sediments. Onshore deposits were studied in Abu Dhabi and Qatar. At least two sequences of Pleistocene carbonates are preserved onshore in the southern Arabian Gulf. These comprise, firstly, widespread aeolianites deposited prior to the last interglacial (the Ghayathi Formation), and secondly, marine sediments and aeolianites deposited during the last interglacial (the Fuwayrit Formation). Marine deposits of the Fuwayrit Formation indicate that sea-level was higher than present on two occasions during the last (Sangamonian) interglacial.

No description available.

Thesis (PhDGeology)--University of South Australia, 2000.

Thesis (PhD) -- University of South Australia, 1998

Thesis (PhD) -- University of South Australia, 1998