A model for bottom‐hole temperature stabilization

Geophysics ◽  
1979 ◽  
Vol 44 (8) ◽  
pp. 1458-1462 ◽  
Author(s):  
M. F. Middleton
Keyword(s):  
South Australia ◽  
Alternative Methods ◽  
Drilling Fluids ◽  
Cylindrical Shape ◽  
Deep Well ◽  
Bottom Hole ◽  
Rectangular Coordinates ◽  
Basal Portion ◽  
Gas Fields ◽  
Cooper Basin

Bottom‐hole temperature (BHT) stabilization is modeled assuming that the mud temperature in a deep well is uniform for several meters above its base and that the basal portion of the well was formed rapidly so that it may be considered to have formed “instantaneously”. Therefore, knowledge of circulation time of the drilling fluids, which is required in many alternative methods of correction for BHT disturbance, is not necessary. Rectangular coordinates are used to describe the geometrical configuration of the well, which often departs from an ideal cylindrical shape due to caving of poorly consolidated formations. True formation temperature can be found by a simple curve‐matching technique if several time‐sequential BHT measurements are available. This technique is successfully applied to BHT data from a number of wells in the Moomba and Big Lake gas fields of the Cooper Basin, South Australia.

EXPLORATION IN THE COOPER BASIN

1989 ◽  
Vol 29 (1) ◽  
pp. 366 ◽  
Author(s):  
R. Heath
Keyword(s):  
Oil And Gas ◽  
South Australia ◽  
Mature Stage ◽  
Small Contribution ◽  
Terrestrial Source ◽  
Seismic Acquisition ◽  
Proterozoic Basement ◽  
Gas Fields ◽  
Coal Measures ◽  
Cooper Basin

The Cooper Basin is located in the northeastern corner of South Australia and in the southwestern part of Queensland. The basin constitutes an intracratonic depocentre of Permo- Triassic age. The Cooper Basin succession unconformably overlies Proterozoic basement as well as sediments and metasediments of the Cambro- Ordovician age. An unconformity separates in turn the Cooper succession from the overlying Jurassic- Cretaceous Eromanga Basin sediments.The Permo- Triassic succession comprises several cycles of fluvial sandstones, fluvio- deltaic coal measures and lacustrine shales. The coal measures contain abundant humic kerogen, comprising mainly inertinite and vitrinite with a small contribution of exinite. All hydrocarbon accumulations within the Cooper Basin are believed to have originated from these terrestrial source rocks.Exploration of the basin commenced in 1959 and, after several dry holes, the first commercial discovery of gas was made at Gidgealpa in 1963. To date, some 97 gas fields and 10 oil fields, containing recoverable reserves of 5 trillion cubic feet of gas and 300 million barrels recoverable natural gas liquids and oil, have been discovered in the Cooper Basin. Production is obtained from all sand- bearing units within the Cooper stratigraphic succession.The emphasis of exploration in the Cooper Basin is largely directed towards the assessment of four- way dip closures and three- way dip closures with fault control, but several stratigraphic prospects have been drilled. Furthermore, in the development phase of some gas fields a stratigraphic component of the hydrocarbon trapping mechanism has been recognised.Improvements in seismic acquisition and processing, combined with innovative thinking by the explorers, have facilitated the development of untested structural/stratigraphic plays with large reserves potential. Exploration for the four- and three- way dip closure plays in the Cooper Basin is now at a mature stage. However, reserves objectives are expected to continue to be met, with the expectation of a continuing high success rate.Selected new plays are expected to be tested within a continuing active exploration program as exploration for oil and gas in the Cooper Basin refines the search for the subtle trap.

Applications of Nanomaterials in Wellbore Fluids in Oil and Gas Fields

2021 ◽  
Vol 881 ◽  
pp. 33-37
Author(s):  
Wei Na Di
Keyword(s):  
Oil And Gas ◽  
Drill String ◽  
Wellbore Stability ◽  
Petroleum Engineering ◽  
Cement Stone ◽  
Drilling Fluids ◽  
Cement Slurry ◽  
Oil And Gas Fields ◽  
Gas Channeling ◽  
Gas Fields

The application of nanomaterials in oil and gas fields development has solved many problems and pushed forward the development of petroleum engineering technology. Nanomaterials have also been used in wellbore fluids. Nanomaterials with special properties can play an important role in improving the strength and flexibility of mud cake, reducing friction between the drill string and wellbore and maintaining wellbore stability. Adding nanomaterials into the cement slurry can eliminate gas channeling through excellent zonal isolation and improve the cementing strength of cement stone, thereby facilitating the protection and discovery of reservoirs and enhancing the oil and gas recovery. This paper tracks the application progress of nanomaterials in wellbore fluids in oil and gas fields in recent years, including drilling fluids, cement slurries. Through the tracking and analysis of this paper, it is concluded that the applications of nanomaterials in wellbore fluids in oil and gas fields show a huge potential and can improve the performance of wellbore fluids.

Exploring for stratigraphic traps in the Patchawarra Formation, Cooper Basin: an integrated seismic methodology

2018 ◽  
Vol 58 (2) ◽  
pp. 779
Author(s):  
Alexandra Bennett
Keyword(s):  
Complex Geometry ◽  
Imaging Techniques ◽  
South Australia ◽  
Seismic Interpretation ◽  
Seismic Survey ◽  
3D Seismic ◽  
Seismic Resolution ◽  
Seismic Reflectivity ◽  
Seismic Area ◽  
Cooper Basin

The Patchawarra Formation is characterised by Permian aged fluvial sediments. The conventional hydrocarbon play lies within fluvial sandstones, attributed to point bar deposits and splays, that are typically overlain by floodbank deposits of shales, mudstones and coals. The nature of the deposition of these sands has resulted in the discovery of stratigraphic traps across the Western Flank of the Cooper Basin, South Australia. Various seismic techniques are being used to search for and identify these traps. High seismic reflectivity of the coals with the low reflectivity of the relatively thin sands, often below seismic resolution, masks a reservoir response. These factors, combined with complex geometry of these reservoirs, prove a difficult play to image and interpret. Standard seismic interpretation has proven challenging when attempting to map fluvial sands. Active project examples within a 196 km2 3D seismic survey detail an evolving seismic interpretation methodology, which is being used to improve the delineation of potential stratigraphic traps. This involves an integration of seismic processing, package mapping, seismic attributes and imaging techniques. The integrated seismic interpretation methodology has proven to be a successful approach in the discovery of stratigraphic and structural-stratigraphic combination traps in parts of the Cooper Basin and is being used to extend the play northwards into the 3D seismic area discussed.

scholarly journals EXPLOITATION OF GAS WELLS IN LATE STAGE OF DEVELOPMENT OF GAS FIELDS

2017 ◽  
pp. 85-89 ◽  
Author(s):  
V. V. Panikarovskii ◽  
E. V. Panikarovskii
Keyword(s):  
Production Rate ◽  
Late Stage ◽  
Gas Condensate ◽  
Gas Wells ◽  
Stage Of Development ◽  
Bottom Hole ◽  
Basic Technology ◽  
Water Cut ◽  
Foam Forming ◽  
Gas Fields

At late stage of development of gas fields they need to solve the specific issues of increasing the production rate of wells and decreasing water cut. The available experience of development of gas and gas condensate fields proves, that the most effective method of removing of water, accumulating in wells, is an injection into the bottom hole zone of foam-forming compositions, based on surfactants. The most technological in the application was the use of solid and liquid surfactants. Installation in wells of lift columns of smaller diameter ensured the removal of liquid from the bottom hole of wells, but after few month of exploitation the conditions of removal of liquid from the bottom hole of wells deteriorate. The technologies of concentric lift systems and plunger-lift systems are used in small number of wells. The basic technology for removal of liquid from bottom hole of gas wells at present time is the technology of treatment of bottom hole of wells with solid surfactants.

HIGH RESOLUTION PALAEOGEOGRAPHIC MAPPING OF THE FLUVIAL-LACUSTRINE PATCHAWARRA FORMATION IN THE COOPER BASIN, SOUTH AUSTRALIA

2002 ◽  
Vol 42 (1) ◽  
pp. 65 ◽  
Author(s):  
P.C. Strong ◽  
G.R. Wood ◽  
S.C. Lang ◽  
A. Jollands ◽  
E. Karalaus ◽  
...  
Keyword(s):  
High Resolution ◽  
South Australia ◽  
River System ◽  
Structural Features ◽  
Gas Reservoirs ◽  
Predictive Tool ◽  
Sequence Stratigraphic ◽  
Channel Belt ◽  
Reservoir Connectivity ◽  
Cooper Basin

Fluvial-lacustrine reservoirs in coal-bearing strata provide a particular challenge for reservoir characterisation because of the dominance of coal on the seismic signature and the highly variable reservoir geometry, quality and stratigraphic connectivity. Geological models for the fluvial gas reservoirs in the Permian Patchawarra Formation of the Cooper Basin are critical to minimise the perceived reservoir risks of these relatively deep targets. This can be achieved by applying high-resolution sequence stratigraphic concepts and finescaled seismic mapping. The workflow begins with building a robust regional chronostratigraphic framework, focussing on widespread lacustrine flooding surfaces and unconformities, tied to seismic scale reflectors. This framework is refined by identification of local surfaces that divide the Patchawarra Formation into high-resolution genetic units. A log facies scheme is established based on wireline log character, and calibrated to cores and cuttings, supported by analogue studies, such as the modern Ob River system in Western Siberia. Stacking patterns within each genetic unit are used to determine depositional systems tracts, which can have important reservoir connectivity implications. This leads to the generation of log signature maps for each interval, from which palaeogeographic reconstructions are generated. These maps are drawn with the guiding control of syn-depositional structural features and net/ gross trends. Estimates of fluvial channel belt widths are based on modern and ancient analogues. The resultant palaeogeography maps are used with structural and production data to refine play concepts, as a predictive tool to locate exploration and development drilling opportunities, to assess volumetrics, and to improve drainage efficiency and recovery during production of hydrocarbons.

Temperature-dependent stability of deep wells in the Cooper Basin

2010 ◽  
Vol 50 (2) ◽  
pp. 734
Author(s):  
Fermin Fernandez-Ibañez ◽  
David Castillo ◽  
Doone Wyborn ◽  
Dean Hindle ◽  
Adrian White
Keyword(s):  
Thermal Stresses ◽  
High Heat ◽  
In Situ Stress ◽  
Silica Content ◽  
Granitic Rocks ◽  
Drilling Fluids ◽  
Radiogenic Heat ◽  
Collapse Pressure ◽  
Compressive Stresses ◽  
Cooper Basin

The Cooper-Eromanga Basin is characterised by high heat flow that has been related to the presence of high radiogenic heat-producing granites. Several wells have been drilled in the area to exploit the heat from the fractured granitic rocks of the basement. Drilling through the hot formations in the Cooper Basin (max. temperature ca. 250 °C) with relatively cool drilling fluids induces an almost instantaneous cooling of the wellbore wallrock. Cooling of the hole (the usual case) increases the tensile stresses (and decreases the compressive stresses) at the wellbore wall. The magnitude of the thermal stresses is also dependent on the silica content of the formation. Modelling of the in situ stress tensor and mechanical properties of the wellbore rocks has revealed the time-dependent effect that the borehole collapse pressure has on the stability of the wells. Narrow breakouts form at the time of drilling. Afterwards, the temperature difference (ΔT) decays with time, and as the hole warms up compressive stresses increase and breakouts become enhanced. Therefore, if a high ΔT and a short well exposure time are achieved, it would be possible to inhibit breakout development, drill with a lower mud weight (eventually underbalanced), and, thus, minimise the risk of formation damage.

A reserves driven view of the eastern Australian gas supply and demand balance through the 2020's

2017 ◽  
Vol 57 (2) ◽  
pp. 526
Author(s):  
Will Pulsford
Keyword(s):  
Supply And Demand ◽  
Critical Role ◽  
South Australia ◽  
Market Outcomes ◽  
Natural Gas Markets ◽  
Eastern Australia ◽  
Gas Market ◽  
Gas Fields ◽  
Key Participants ◽  
Gas Supply

The Australian Energy Market Operator (AEMO) issued a Gas Statement of Opportunities in March 2016, which reports that gas supply to the domestic and liquefied natural gas markets in eastern Australia will be largely satisfied by proved and probable reserves until 2026 and by the addition of contingent resources until 2030. However, in parallel, there are widely reported concerns by energy consumers of insufficient gas supplies to meet demand by the early 2020s and a lack of new gas supplies to replace existing expiring contracts. Gas shortages have already contributed to black outs and load shedding events in South Australia. This paper reviews the eastern Australian gas supply position at a basin level. The AEMO basin level supply forecasts are reviewed and adjusted to generate forward profiles, which are consistent with reported reserves levels, production histories and depletion behaviour of typical gas fields. The revised supply forecast is compared with the AEMO’s demand profiles, and the likely commercial behaviour of key participants in the market is considered to build a picture of the domestic gas supply-demand balance through the 2020s. This analysis provides a transparent link from market outcomes back to the underlying reserves classifications to guide interpretation of supply-demand forecasts, and highlights the critical role of key suppliers in the eastern Australian gas market in the coming decade.

Sign in / Sign up

Export Citation Format

Share Document