REGIONAL SIGNIFICANCE OF THE ARQUEBUS- I WELL, BROWSE BASIN, NORTH WEST SHELF, AUSTRALIA

1993 ◽  
Vol 33 (1) ◽  
pp. 28 ◽  
Author(s):  
Roger B. Haston ◽  
John J. Farrelly

The Arquebus-1 well was drilled in 1991 on exploration permit WA-206-P located in the southern portion of the Browse Basin. The Browse Basin is one of the least explored offshore basins in Australia and although two major gas discoveries have been made, no significant oil accumulations have been found. The Arquebus-1 well tested Middle to Upper Jurassic sandstones in a large three-way dip closed structure along the main Jurassic basin margin fault system, which has subsequently been inverted by Tertiary wrench faulting. The well was plugged and abandoned despite the presence of numerous shows and pay indicated by wireline logs. Five formation tests were performed and despite a long 12-hour test, only mud filtrate was recovered, suggesting that significant fluid invasion had occurred. The pressure data indicate a good water gradient with a 51 m gross column of light oil and gas. This is supported by detailed analysis of fluid inclusions, capillary pressure analysis, wireline logs and sidewall cores. The total gross hydrocarbon column may be as great as 105 m. The extremely low clay content, the uniform pore throat size, the slow drilling rate and the overbalanced drill mud made the sandstones prone to the nearly complete flushing of formation fluids and associated formation damage. The presence of an inferred oil column in the Jurassic sandstones at Arquebus-1, indicates that oil has been generated in the Browse Basin and that three-way dip closed structures are potentially viable traps in the area.

2021 ◽  
Vol 61 (2) ◽  
pp. 640
Author(s):  
Abdul Kholiq ◽  
Claire Jacob ◽  
Bee Jik Lim ◽  
Oliver Schenk ◽  
Anubrati Mukherjee ◽  
...  

The Exmouth Sub-basin represents part of the intracratonic rift system of the northern Carnarvon Basin, Australia. Hydrocarbon exploration has resulted in the discovery of a variety of oil and gas accumulations, mainly in Upper Triassic, Upper Jurassic and Lower Cretaceous intervals. Recent 3D petroleum systems modelling aided in understanding the interaction of the complex basin evolution and hydrocarbon charge history, shedding light on the variety and distribution of hydrocarbon types encountered, whilst also highlighting future remaining potential in both proven and untested plays. As a result of this modelling, the Exmouth Subsurface Characterisation Study was commissioned to further leverage >12000km2of recently acquired and processed seismic data and integrate data from specifically conditioned wells from across the Exmouth Sub-basin. The primary study objective was to better understand the distribution of lithologies across the basin, with focus upon the reservoir presence and properties over proven and potential deeper sections. Furthermore, given the variety of hydrocarbon types encountered, this study set out to understand the amplitude behaviour of these types within the different reservoirs. Collectively, these results have aided in identifying analogous hydrocarbon amplitude responses across the basin, derisking identified plays, prospects and existing discoveries and fields whilst also identifying new plays and leads.


1991 ◽  
Vol 14 (1) ◽  
pp. 353-360 ◽  
Author(s):  
P. Waddams ◽  
N. M. Clark

AbstractPetronella Field is a small oil and gas accumulation located 110 miles northeast of Aberdeen in UK Block 14/20b. The field lies on the highest part of the east-west-trending Petronella Ridge approximately 6 miles southwest of the Witch Ground Graben axis. The reservoir is Upper Jurassic in age and lies some 7500 ft below sea level. It comprises shallow marine sandstone of the Piper Formation ('Principal Reservoir Sequence') overlain by deeper marine turbidites ('Hot Lens Equivalent') of the Kimmeridge Clay Formation. The structure is a tilted fault block which is bounded to the north by a major fault system, downthrown to the north. Sandstone units dip to the south and thin or are truncated to the north as a result of erosion of the crest of the structure. Seal is effected by Upper Jurassic siltstone and Lower Cretaceous calcareous claystone. The accumulation has been sourced from maturation of the Kimmeridge Clay Formation below approximately 10000 ft in adjacent basins. The Field was discovered in February 1975 and is delineated by six wells. Current production of 13 000 BOPD comes from one well and uses an innovative remote subsea system controlled from, and with pipelines to, the Tartan Platform 6.4 miles to the east. Ultimate recoverable reserves from the main portion of the Field are 17 MMBBL of crude oil.


Geophysics ◽  
2003 ◽  
Vol 68 (1) ◽  
pp. 58-69 ◽  
Author(s):  
Hendrik Braaksma ◽  
Jeroen A. M. Kenter ◽  
Jean Noel Proust ◽  
Vincent Dijkmans ◽  
Tomas van Hoek ◽  
...  

More than 200 plugs from outcrop and a nearby borehole in a carbonaceous siliciclastic interval of Late Jurassic (Kimmeridgian to Tithonian) age were quantitatively analyzed for texture, mineralogy, and acoustic properties. Our primary goal was to study the effect of clay (fraction smaller than 8 μm), silt/sand (fraction larger than 8 μm), and carbonate on the acoustic properties. The quantitative nature and volume of the data made it possible to observe four‐dimensional relationships in contoured ternary diagrams. Primary control on the acoustic properties is exerted by porosity, but the trend of this relationship significantly deviates from popular velocity transforms. The contribution of clay, silt/sand, and carbonate particular material and cement explains the remaining variation in acoustic properties. Although no clear linear thresholds are defined, a general trend is that clay and carbonate content have opposite and overlapping effects on acoustic properties, the influence of clay content progressively increases with decreasing carbonate content, and visa versa. With increasing carbonate content, the variation of acoustic velocity at a given porosity value increases to nearly twice of that in the clay‐dominated sediment. Traditional classification boundaries are present but strongly overprinted by this interplay between clay and carbonate. This study may have important implications for porosity and lithofacies prediction from wireline logs in similar mixtures of sediment. In addition, the quantitative character of the textural and mineralogical data may provide a direct link from acoustic properties to the primary depositional system and sequence stratigraphy.


2002 ◽  
Vol 8 (2-3) ◽  
pp. 206-208
Author(s):  
V.G. Osadchyi ◽  
◽  
O.A. Prykhod'ko ◽  
I.I. Hrytsyk ◽  
◽  
...  

2012 ◽  
Vol 616-618 ◽  
pp. 174-184
Author(s):  
Yong He Sun ◽  
Lin Kang ◽  
Feng Xiang Yang ◽  
Xue Song Li

In order to reveal in middle fault depression belt of Hailer-Tamtsag Basin buried hill oil and gas migration and accumulation characteristics, we summarize controlling effect of fault on oil and gas migration and accumulation of buried hill, which by analysing genetic mechanism of buried hills based on fault systems formation and evolution. Research shows that three types of fault system in Hailer-Tamtsag Basin: early stretched fault system(Type I), early stretched middle tensile shearing fault system(Type I-II), early stretched middle tensile shearing reverse late fault system(Type I-II-III). Type I-II and I-II-III are stretching by NW tensional stress in Nantun group ,which afford tectonic framework for syngenesis buried hill and epigenetic buried hill. Type I make buried hills complicated .It is also favorable to ancient geomorphological buried hill in the fault less affected zones. Although they formed cracks dense zone easier, Type I-II and I-II-III fault system damage the reservoir which is not conducive to " hydrocarbon-supplying window " formation; Type I fault system have less promotion on the development of the buried hill reservoir, while it is conducive to hydrocarbon accumulation as the block boundary in buried hill hydrocarbon. Fault formed source rocks two kinds for hydrocarbon mode: unidirectional and bidirectional, which formed two reservoir-forming pattern: Unidirectional transportation hydrocarbon of weathering crust or hydrocarbon of fracture damage zones and bidirectional transportation hydrocarbon of weathering crust or hydrocarbon of fracture damage zones.


2021 ◽  
pp. 1-36
Author(s):  
Zhiwei Xiao ◽  
Li Wang ◽  
Ruizhao Yang ◽  
Dewei Li ◽  
Lingbin Meng

An ultradeep, faulted karst reservoir of Ordovician carbonate was discovered in the Shunbei area of the Tarim Basin. Fractured-cavity reservoirs buried beneath the large thickness of upper Ordovician mudstone were formed along the fault-karst belts. The hydrocarbon accumulation in these reservoirs is controlled by the fault system, and the oil-gas accumulation was affected by karstification and hydrothermal reformation. Previous studies and 2D modeling revealed that the reservoirs had “bright spot” amplitude responses like “string beads,” and they have developed along the strike-slip faults. However, describing such a complex fault-controlled karst system is still a difficult problem that has not been well addressed. We have sought to instruct the attribute expression of faulted karst reservoirs in the northern part of the Tarim Basin. We applied coherence and fault likelihood (FL) seismic attributes to image faults and fractures zones. We then used a trend analysis method to calculate the residual impedance from the impedance of the acoustic inversion, using the fact that residual impedance has higher lateral resolution in reservoir predictions. Finally, we integrated the coherence, FL, and residual impedance attributes into a new seismic attribute, the “fault-vuggy body,” with a certain fusion coefficient. The fault-vuggy body attribute establishes a connection between faults and karst cavities. This method could help in the characterization and prediction of carbonate faulted karst reservoirs. Available drilling data were used to validate that the fused fault-vuggy body attribute was an effective reservoir prediction method. As the seismic sections and slices along the layer help delineate, the distribution of bright spots and strike-slip faults indicates that the main strike-slip fault zones are the most favorable reservoirs in the Shunbei Oil and Gas Field.


2021 ◽  
pp. M57-2020-20
Author(s):  
E. Henriksen ◽  
D. Ktenas ◽  
J. K. Nielsen

AbstractThe Finnmark Platform Composite Tectono-Sedimentary Element (CTSE), located in the southern Barents Sea, is a northward-dipping monoclinal structural unit. It covers most of the southern Norwegian Barents Sea where it borders the Norwegian Mainland. Except for the different age of basement, the CTSE extends eastwards into the Kola Monocline on the Russian part of the Barents Sea.The general water depth varies between 200-350 m, and the sea bottom is influenced by Plio-Pleistocene glaciations. A high frequency of scour marks and deposition of moraine materials exists on the platform areas. Successively older strata sub-crop below the Upper Regional Unconformity (URU, which was) formed by several glacial periods.Basement rocks of Neoproterozoic age are heavily affected by the Caledonian Orogeny, and previously by the Timanide tectonic compression in the easternmost part of the Finnmark Platform CTSE.Depth to crystalline basement varies considerably and is estimated to be from 4-5 to 10 km. Following the Caledonian orogenesis, the Finnmark Platform was affected by Lower to Middle Carboniferous rifting, sediment input from the Uralian Orogen in the east, the Upper Jurassic / Lower Cretaceous rift phase and the Late Plio-Pleistocene isostatic uplift.A total of 8 exploration wells drilled different targets on the platform. Two minor discoveries have been made proving presence of both oil and gas and potential sandstone reservoirs of good quality identified in the Visean, Induan, Anisian and Carnian intervals. In addition, thick sequences of Perm-Carboniferous carbonates and spiculitic chert are proven in the eastern Platform area. The deep reservoirs are believed to be charged from Paleozoic sources. A western extension of the Domanik source rocks well documented in the Timan-Pechora Basin may exist towards the eastern part of the Finnmark Platform. In the westernmost part, charge from juxtaposed down-faulted basins may be possible.


2017 ◽  
pp. 34-43
Author(s):  
E. E. Oksenoyd ◽  
V. A. Volkov ◽  
E. V. Oleynik ◽  
G. P. Myasnikova

Based on pyrolytic data (3 995 samples from 208 wells) organic matter types of Bazhenov Formation are identified in the central part of Western Siberian basin. Zones of kerogen types I, II, III and mixed I-II and II-III are mapped. Content of sulfur, paraffins, resins and asphaltenes, viscosity, density, temperature and gas content in oils from Upper Jurassic and Lower Cretaceous sediments (3 806 oil pools) are mapped. Oil gradations are identified and distributed. The alternative model of zones of kerogen II and IIS types is presented. The established distributions of organic matter types can be used in basin modeling and in assessment of oil-and-gas bearing prospects.


2021 ◽  
Vol 43 (4) ◽  
pp. 199-216
Author(s):  
N.P. Yusubov ◽  
I.S. Guliyev

The high degree of knowledge of the upper horizons of the sedimentary cover of the Middle and South Caspian depressions, given an insufficient increase in hydrocarbon reserves, leads to the need for a detailed approach to the search for oil and gas deposits in deep-seated sediments (over 6 km). During the geological interpretation of new highly informative seismic data, as well as data of deep drilling and petrological core studies, there were revealed obvious shortcomings in the concepts of the origin and evolution of the Middle and South Caspian depressions. These ideas misinterpret evolution, especially the South Caspian Basin, which is characterized by a number of unique features: very thick sedimentary cover (up to 22 km), extremely high sedimentation rate, low heat flow and reservoir temperatures, abnormally high pore and reservoir pressures, high clay content of the section, etc. The main purpose of the study was to elucidate the regional structure and features of the dissection of the sedimentary cover of the Middle and South Caspian depressions, the conditions of occurrence and distribution of facies and thicknesses of individual complexes of deposits. The paper analyzes the results of some previous studies of the geological structure of the Middle and South Caspian depressions based on the data of deep seismic sounding, seismological and gravimetric observations. We consider the main conclusions of these studies, about the geological structure of the sedimentary complex of the region’s, very outdated and subject to revision. The results of seismic stratigraphic analysis of seismic data allowed the authors to identify new data about the tectonic structure and express a completely different point of view regarding the structure of the sedimentary cover in the region. The work also touches on the issue associated with the tectonics of the region and the alleged subduction zone here.


Sign in / Sign up

Export Citation Format

Share Document