Honours and Coursework
Permanent URI for this community
This collection contains Masters and Ph.D by coursework theses from University of Adelaide postgraduate students.
Some schools may choose to include Honours theses which make a significant contribution to knowledge.
News
For further information about the collection, please contact the Library Theses team
Browse
Browsing Honours and Coursework by Advisors "Amos, Kathryn"
Now showing 1 - 3 of 3
Results Per Page
Sort Options
Item Open Access Geocellular modelling and connectivity analysis of a tide-influenced channel belt system: example from the Mitchell River Delta, Gulf of Carpentaria, Australia(2014) Al Quwaitii, Reham Said; Amos, Kathryn; Holford, Simon Paul; Australian School of PetroleumThe interaction of tidal and fluvial processes in marginal marine settings, particularly tidally influenced channel systems, can produce profound lateral and vertical facies heterogeneity, in forms such as Lateral Accretion Packages (LAPs) and Inclined Heterolithic Stratification (IHS). LAPs form at the convex banks of sinuous channels, and can be composed of either homogeneous or heterogeneous deposits. Within tidal reaches, they are often comprised of IHS deposits. IHS deposits are inclined alternating shale and sand layers that form by laterally accreting fluvial-estuarine point bars. Understanding the 3D distribution of tidally influenced channel architectures in modern channel systems has important implications for the effective modelling of subsurface channel reservoir distribution, connectivity and fluid flow. In this research, 3D geocellular modelling of a selected modern point bar from the Mitchell River system, Gulf of Carpentaria (GoC), Queensland, Australia, is used to predict heterogeneity and connectivity associated with a tidally influenced channel reservoir system. The modelling workflow consisted of four main stages: (a) data integration, (b) mapping, (c) geocellular modelling and (d) connectivity assessment. Analysis of high-resolution satellite imagery merged with Shuttle Radar Topography Mission Digital Elevation Models data for an area of 14.57 km × 2.34 km allowed direct mapping and measurement of dimensions and orientation of the stratigraphic architecture of the selected point bar geometry. Core and auger well log data and a stratigraphic cross section oriented perpendicular to the channel axis were used in order to constrain the stratigraphic architecture and the facies distribution. Five facies were identified in the studied point bar strata, including Lag Sand Deposits with rippled sandstone 2.5 m thick, which is common in upstream locations on the point bar, and heterogeneous sand and mud facies. Inclined heterolithic mud deposits (IHS) are confined to the upper 3 m of the point bar. As the focus of this project is the impact of IHS on reservoir connectivity, a new approach was proposed to resolve the heterogeneity associated with tidally influenced channel systems, by developing three geological models based on the presence and continuity of IHS deposits (the products of fluvial and tidal interaction processes). Connectivity analysis of the three realisations showed marked contrast between models using point bar geobodies. The tide-dominated, fluvial-influenced channel system represents the worst reservoir connectivity in the subsurface, as the volume contains considerable bodies of mainly mud facies. Although there are significant objects in this point bar model, the majority of these bodies are very small and supposedly form 75% mudstone of the total volume. In scenario two (Ft channel system; fluvial dominated, tidally influenced channel system), the model suggests fluid flow will preferentially concentrate in the lower part of the point bar, where clean sand sediments form a continuous body. The geo-volume in realization three (F channel system; fluvial dominated channel system) reflects the connectivity of the channel comprised of just the point bar object, which can represent best reservoir continuity and limited compartmentalization. Thus, reservoir quality increases as the fluvial process in the channel system becomes more dominant. We recommend that further field work, such as a new stratigraphic cross sections, should be obtained parallel to the channel axis in order to capture 3D heterogeneity within tidally influenced channel systems, and that the Fullbore Formation Microimager tool should be used to obtain the corrected inclination of IHS deposits.Item Open Access Sedimentology and stratigraphy of the Late Neoproterozoic Bonney Sandstone(2014) Koyejo, Oyinloye; Amos, Kathryn; Counts, John; Australian School of PetroleumThis study represents the first good detailed sedimentological and sequence stratigraphic analysis of the Bonney Sandstone exposed at the Arkaroola Syncline in the Northern part of Flinders Ranges, South Australia. The Bonney Sandstone is located between two prominent Late Neoproteozoic Formations, the underlying Wonoka Formation and overlying Rawnsley Quartzite. These rocks have become significant in recent years due to their importance in hydrocarbon exploration in salt withdrawal basins. However there are few published studies on the Bonney Sandstone. Ten lithofacies were identified which formed the five facies associations. These facies associations include Offshore deposits (FA 5), Offshore transition deposits (FA 4), Shoreface/Foreshore deposits (FA 3), Mixed Wave-Tidal delta deposits (FA 2) and Channel Deposits (FA 1). These facies association represent three major depositional environments, shallow marine, mixed wave-tidal delta and fluvial deposit. Sequence stratigraphically, there are shows two significate intervals. The lower transgressive interval which is made up of siltstone deposits with interbedded massive sandstones. Low stand system tract deposit which marked the boundary between the Wonoka Formation and the Bonney Sandstone. The middle to upper section essentially represents a highstand system tract with normal regression. The normal regressive interval was characterised by prograding delta and aggrading channel sandstone deposit. Cyclicity pattern within the Bonney Sandstone are made up of third and fourth order cycles. Eastern paleocurrent directions suggest palaeo flow towards the Arkaroola Syncline. Petrographic interpretation shows basement source rocks with deposition in a low topographic area with little or no exposure of sediments. Adverse effects of prevailing climatic conditions significantly affected sediment deposition as observed within the grain size, mineralogical composition and reservoir potential of the Bonney Sandstone. Reservoir quality of the Bonney Sandstone is essentially low due very poor porosity and permeability.Item Open Access Stratigraphy and sedimentology of the Late Neoproterozoic Bonney Sandstone, Northern Flinders Ranges, South Australia(2014) Liu, Limeng; Amos, Kathryn; Counts, John; Australian School of PetroleumThe Adelaide Geosyncline is considered as a deformed sedimentary basin located between the Paleoproterozoic Gawler and Curnamona crystalline basement complexes. A suite of Late Neoproterozoic clastic sediments are widely deposited in the Flinders Ranges, South Australia. From the Proterozoic to the Cambrian, this area was a passive margin system. The outstanding exposures in this region allow detailed study of the sedimentary structures of analogous basins around the world, which often contain similar styles of source rocks and petroleum reservoirs. The Bonney Sandstone in the Northern Flinders Ranges is the lower part of the coarser, shallow-marine Pound Subgroup. This project provides an opportunity to examine relatively undescribed strata in this area. During the fieldtrip, my investigation consists of two detailed measured stratigraphic sections, which reveal a few well-preserved primary sedimentary structures. Many detailed sedimentological analysis were done during the study, including the measurement of strata and petrography. Several lithofacies were summarized and the associations of them were discovered. The characteristics of sedimentation are influenced by the paleocurrent, sediment supply and basin development. Both the modelling of this sedimentary process and the palaeogeography of the Neoproterozoic of South Australia are required to better understand the sedimentary character in the Northern Flinders Ranges.