RESERVOIR GEOMETRY OF FLUVIAL DISTRIBUTARY CHANNELS—IMPLICATIONS FOR NORTHWEST SHELF, AUSTRALIA, DELTAIC SUCCESSIONS

2003 ◽  
Vol 43 (1) ◽  
pp. 325 ◽  
Author(s):  
T.H.D. Payenberg ◽  
S.C. Lang
Keyword(s):  
Detailed Knowledge ◽  
North West ◽  
Reservoir Characteristics ◽  
Delta Plain ◽  
The North ◽  
Meander Channel ◽  
Mahakam Delta ◽  
Rectilinear Channel ◽  
Distributary Channel ◽  
Exploration And Development

The exploration and development of stratigraphically trapped hydrocarbons requires detailed knowledge of the morphologies and reservoir characteristics of the stratigraphic body. Fluvial distributary channels are important exploration targets because they are typically isolated reservoirs, laterally and vertically sealed by delta plain and abandoned channel mudstone, and thus form excellent stratigraphic traps. The morphology and reservoir characteristics of fluvial distributary channels have been confused with fluvial channels in the past. Knowing the characteristics of fluvial distributary channels and their difference from fluvial channels is the key to the successful exploration and development of distributary channel reservoirs.Fluvial distributary channels, formed by mixed-load systems, are commonly rectilinear channel segments found only on the delta plain between the head of passes and the depositional mouthbars. While fluvial channel reservoirs are mainly sandstone deposits of meander pointbars or braided sheets, fluvial distributary channel reservoirs are typically elongated sandy channel sidebars attached to morphologically rectilinear channel walls. The sidebars form by both lateral and downstream accretion resulting from flow in a confined, but lowsinuosity thalweg, which may be filled with organic mud following channel abandonment. On 3D seismic data the morphology of a fluvial distributary channel is often slightly sinuous and can easily be mistaken for part of a meander channel belt.Fluvial distributary channels are usually thinner and shallower compared to their updip fluvial channel belts. Width-thickness ratios for fluvial distributary channel reservoirs are on average 50:1 (range 15:1 to 100:1), while meandering fluvial channel reservoirs have widththickness ratios typically >100:1, and braided river reservoirs show ratios of 500:1 or higher. Examples from the Mahakam Delta are used to illustrate these issues. Implications for exploration and development of deltaic deposits on the North West Shelf of Australia are discussed.

DEMETER HIGH RESOLUTION 3D SEISMIC SURVEY—REVITALISED DEVELOPMENT AND EXPLORATION ON THE NORTH WEST SHELF, AUSTRALIA

2006 ◽  
Vol 46 (1) ◽  
pp. 101 ◽  
Author(s):  
K.J. Bennett ◽  
M.R. Bussell
Keyword(s):  
High Resolution ◽  
Seismic Data ◽  
New Technologies ◽  
Seismic Survey ◽  
Future Application ◽  
3D Seismic ◽  
Gas Field ◽  
North West ◽  
The North ◽  
Exploration And Development

The newly acquired 3,590 km2 Demeter 3D high resolution seismic survey covers most of the North West Shelf Venture (NWSV) area; a prolific hydrocarbon province with ultimate recoverable reserves of greater than 30 Tcf gas and 1.5 billion bbls of oil and natural gas liquids. The exploration and development of this area has evolved in parallel with the advent of new technologies, maturing into the present phase of revitalised development and exploration based on the Demeter 3D.The NWSV is entering a period of growing gas market demand and infrastructure expansion, combined with a more diverse and mature supply portfolio of offshore fields. A sequence of satellite fields will require optimised development over the next 5–10 years, with a large number of wells to be drilled.The NWSV area is acknowledged to be a complex seismic environment that, until recently, was imaged by a patchwork of eight vintage (1981–98) 3D seismic surveys, each acquired with different parameters. With most of the clearly defined structural highs drilled, exploration success in recent years has been modest. This is due primarily to severe seismic multiple contamination masking the more subtle and deeper exploration prospects. The poor quality and low resolution of vintage seismic data has also impeded reservoir characterisation and sub-surface modelling. These sub-surface uncertainties, together with the large planned expenditure associated with forthcoming development, justified the need for the Demeter leading edge 3D seismic acquisition and processing techniques to underpin field development planning and reserves evaluations.The objective of the Demeter 3D survey was to re-image the NWSV area with a single acquisition and processing sequence to reduce multiple contamination and improve imaging of intra-reservoir architecture. Single source (133 nominal fold), shallow solid streamer acquisition combined with five stages of demultiple and detailed velocity analysis are considered key components of Demeter.The final Demeter volumes were delivered early 2005 and already some benefits of the higher resolution data have been realised, exemplified in the following:Successful drilling of development wells on the Wanaea, Lambert and Hermes oil fields and identification of further opportunities on Wanaea-Cossack and Lambert- Hermes;Dramatic improvements in seismic data quality observed at the giant Perseus gas field helping define seven development well locations;Considerably improved definition of fluvial channel architecture in the south of the Goodwyn gas field allowing for improved well placement and understanding of reservoir distribution;Identification of new exploration prospects and reevaluation of the existing prospect portfolio. Although the Demeter data set has given significant bandwidth needed for this revitalised phase of exploration and development, there remain areas that still suffer from poor seismic imaging, providing challenges for the future application of new technologies.

scholarly journals HIV/AIDS Perceptions, attitudes and awareness of undergraduate students

2006 ◽  
Vol 2 (1) ◽  
Author(s):  
Christo Van Wyk
Keyword(s):  
Undergraduate Students ◽  
Tertiary Education ◽  
Future Research ◽  
Detailed Knowledge ◽  
Cross Sectional ◽  
Convenience Sample ◽  
North West ◽  
The North ◽  
Vaal Triangle ◽  
Hiv Aids

The central question to be examined revolves around the perceptions, attitudes and awareness regarding HIV/AIDS among undergraduate students at the North-West University (Vaal Triangle Campus). Therefore, the objective of this research was to assess these perceptions, attitudes and awareness regarding HIV/AIDS. A convenience sample of undergraduate students was used in a cross-sectional design (N = 290). A semi-standardised questionnaire as well as a biographical questionnaire was administered. The semi-standardised questionnaire was proven to be reliable. Cronbach’s alpha coefficient of between 0.65 and 0.71 was obtained. Descriptive statistics were used to analyse the data. Results indicated that students experienced and perceived differences with regards to their biographical variables in terms of their perceptions, attitudes and awareness regarding HIV/AIDS. Differences were also found between students in different study modules and study years. The findings revealed that the majority of the students were quite knowledgeable regarding HIV/AIDS. While some students had detailed knowledge of the disease and its prevention, others (the minority) were either completely ignorant about it or deny its existence. Recommendations were made for future research in the area of HIV/AIDS within the context of tertiary education.

LEGAL AND TAXATION IMPLICATIONS FOR THE ACQUISITION AND DISPOSAL OF OFFSHORE PETROLEUM PRODUCTION AND EXPLORATION TENEMENTS—A PRACTICAL VIEW AND UPDATE

1986 ◽  
Vol 26 (1) ◽  
pp. 7
Author(s):  
J. Allen ◽  
M. Williamson
Keyword(s):  
Capital Gains ◽  
Capital Gains Tax ◽  
Development Activity ◽  
Resource Rent ◽  
Petroleum Production ◽  
North West ◽  
The North ◽  
Funding Mechanisms ◽  
Exploration And Development ◽  
Offshore Petroleum

The administrative aspects of petroleum mining and exploration companies have become more complex of recent years. One area where this is particularly so is in relation to the livelihood of the industry, i.e. access to tenements.While exploration and development activity onshore has hotted up in particular, offshore activity has been fervent but limited largely to bringing into production fields on the North West Shelf, at Jabiru and new areas in Bass Strait. Generally it is held that the likelihood for discoveries of large fields will be offshore Australia rather than onshore and that present exploration activities offshore are inadequate to maintain Australia's oil self-sufficiency.Recent amendments to the Petroleum (Submerged Lands) Act, a plethora of associated Acts, and proposed new tax imposts (e.g. cash bonus bids, retention licence fees, resource rent tax, and capital gains tax) in relation to the offshore segment of the industry have added significantly to the complexities in planning the acquisition and disposal and ongoing control of tenements. Each of these is examined individually and in conjunction for the benefit of planners and executives administering tenements within their organisations.Both sides of the transaction are viewed with emphasis on their tax positions providing opportunities to control the directions and funding mechanisms for the transaction.

scholarly journals Mapping of Tertiary basalts on the northern Blosseville Kyst, East Greenland

1979 ◽  
Vol 95 ◽  
pp. 85-86
Author(s):  
W.S Watt ◽  
M Watt
Keyword(s):  
Coastal Region ◽  
Fault System ◽  
Detailed Knowledge ◽  
Stratigraphic Sequence ◽  
East Greenland ◽  
North West ◽  
The North ◽  
Field Team

During the 1978 season work carried out by a helicopter-supported field team was concentrated in the region around Kap Dalton and Stenos Gletscher. The work formed a continuation of that carried out in 1975 in the coastal region between Kap Dalton and Steward Ø. The main objectives were to link the stratigraphic sequence of the coastal region to that established for the Scoresby Sund area to the north and north-west. For this it was essential to gain a detailed knowledge of the inland behaviour of the coastal fault system.

SEM and TEM observations of sperm development in the testis of the freshwater fish Oreochromis mossambicus

1990 ◽  
Vol 48 (3) ◽  
pp. 58-59
Author(s):  
Daryl A. Cornish ◽  
George L. Smit
Keyword(s):  
Morphological Characteristics ◽  
Oreochromis Mossambicus ◽  
Breeding Cycle ◽  
Limited Information ◽  
North West ◽  
The North ◽  
Sem And Tem ◽  
Sperm Development ◽  
Ultrastructural Characteristics ◽  
The University

Oreochromis mossambicus is currently receiving much attention as a candidater species for aquaculture programs within Southern Africa. This has stimulated interest in its breeding cycle as well as the morphological characteristics of the gonads. Limited information is available on SEM and TEM observations of the male gonads. It is known that the testis of O. mossambicus is a paired, intra-abdominal structure of the lobular type, although further details of its characteristics are not known. Current investigations have shown that spermatids reach full maturity some two months after the female becomes gravid. Throughout the year, the testes contain spermatids at various stages of development although spermiogenesis appears to be maximal during November when spawning occurs. This paper describes the morphological and ultrastructural characteristics of the testes and spermatids.Specimens of this fish were collected at Syferkuil Dam, 8 km north- west of the University of the North over a twelve month period, sacrificed and the testes excised.

The North West Passage

2014 ◽  
Author(s):  
Roald Amundsen ◽  
Godfred Hansen
Keyword(s):  
North West ◽  
The North
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