THE GEOLOGY OF THE WEST TRYAL ROCKS GAS FIELD

1976 ◽  
Vol 16 (1) ◽  
pp. 157 ◽  
Author(s):  
J.R. Meath ◽  
K.J. Bird
Keyword(s):  
Primary Source ◽  
Lower Jurassic ◽  
Coarse Grained ◽  
The West ◽  
Gas Field ◽  
The North ◽  
Bicarbonate Ions ◽  
Uplifted Block ◽  
High Concentrations ◽  
Combustible Gases

The West Tryal Rocks gas field is located offshore at the western margin of the Barrow Sub- basin, in the Carnarvon Basin of Western Australia. It was discovered by West Australian Petroleum Pty Ltd ( WAPET) in 1973 on a southwesterly extension of the Rankin Platform where, farther north, a number of major gas/condensate discoveries have been made by Burmah Oil Company of Australia Ltd (BOCAL) since 1971.The productive structure at West Tryal Rocks lies at a depth of 3200 m in about 150 m of water. It consists of an elongate north - trending uplifted block of Triassic and possibly Lower Jurassic reservoir rocks called the Mungaroo Beds.The block is unconformably capped by the Lower Cretaceous Muderong Shale which also provides the lateral seal across the bounding faults. The reservoir section dips to the north at a greater rate than does the sealing unconformity so that progressively younger pre-Cretaceous sediments subcrop the unconformity in that direction.Shales of Middle to Late Jurassic age in the Barrow Sub-basin to the east are believed to be the primary source of hydrocarbons, although the overlying Muderong Shale cannot be ruled out.Three main gas-bearing sands have been encountered by the two wells drilled to date. The second well was drilled up-structure from the first and penetrated 144 m of net gas pay of which 133 m is contained in the three sands. The sands are mainly medium to very coarse grained and possess good porosity and permeability.Preliminary reoervvs estimates indicate that the field contains in excess of 28 x 109 m3 (1 x 1012 ft3) of gas (Playford, 1975).The West Tryal Rocks gas field is unique compared to the other Northwest Shelf fields, in that it is slightly overpressured and contains up to 28% of non-combustible gases - predominantly carbon dioxide and nitrogen. Additionally, the field possesses relatively fresh underlying formation waters with high concentrations of bicarbonate ions.

New Evidence Concerning the Original Order of Deposition of the Longmyndian Rocks

1948 ◽  
Vol 85 (2) ◽  
pp. 107-109 ◽  
Author(s):  
John Challinor
Keyword(s):  
Coarse Grained ◽  
The West ◽  
North West ◽  
The Road ◽  
Fine Grained ◽  
Original Order ◽  
The North ◽  
The Hill ◽  
New Evidence ◽  
The Village

During the war a large new quarry was opened in the Longmyndian rocks of Haughmond Hill, Shropshire. It is near the south-east edge of the hill, to the west of the road running north from Upton Magna and one mile from the village. On the sketch-map in the Shrewsbury Memoir (p. 58) two arrows are shown, at about this locality, recording dips of 50° in a south-easterly direction. I was told that there was a very small quarry here before the large quarry was excavated. The present quarry is even larger than that near Haughmond Abbey (Shrewsbury Memoir, p. 48), on the north-west side of the Pre-Cambrian outcrop, and the two quarries offer extensive and splendidly displayed exposures of Longmyndian rocks, one in the coarse-grained Western Longmyndian and the other in the fine-grained Eastern Longmyndian.

Uncommon preservation of dinosaur footprints in a tidal breccia: Eubrontes giganteus from the Early Jurassic Mongisty tracksite of Aveyron, southern France

2021 ◽  
pp. 1-18
Author(s):  
Jean-David Moreau ◽  
Jacques Sciau ◽  
Georges Gand ◽  
Emmanuel Fara
Keyword(s):  
Scale Up ◽  
Lower Jurassic ◽  
Depositional Environments ◽  
Early Jurassic ◽  
Coarse Grained ◽  
Southern France ◽  
Fine Grained ◽  
The North ◽  
Dinosaur Tracks ◽  
First Time

Abstract A recent excavation yielded 118 large tridactyl footprints in the Lower Jurassic Dolomitic Formation of the Causses Basin, at Mongisty in southern France. Most of the tracks are ascribed to Eubrontes giganteus Hitchcock, 1845. They are preserved on a surface of 53 m2 and form parallel rows with a preferential orientation towards the north. Such an abundance and density of E. giganteus is observed for the first time in the Early Jurassic from the Causses Basin. Sedimentological and ichnotaphonomical analyses show that the footprints were made at different time intervals, thus excluding the passage of a large group. In contrast to all other tracksites from the Dolomitic Formation, where tracks are preserved in fine-grained sediments corresponding to low-energy depositional palaeoenvironments, the tracks from Mongisty are preserved in coarse-grained sediment which is a matrix- to clast-supported breccia. Clasts consist of angular to sub-rounded, millimetric to centimetric-scale (up to 2 cm), poorly sorted, randomly oriented, homogeneous dolostone intraclasts floating in a dolomudstone matrix. Sedimentological analysis shows that the depositional environments of Mongisty varied from subtidal to intertidal/supratidal settings in a large and protected flat marsh. The lithology of the track-bearing surfaces indicates that the mudflat of the Causses Basin was sporadically affected by large mud flows that reworked and redeposited mudstone intraclasts coming from the erosion of upstream, dry and partially lithified mud beds. Throughout the world, this type of preservation of dinosaur tracks in tidal matrix- to clast-supported breccias remains rare.

NEW TECHNOLOGY—A MAJOR IMPACT ON A PRODUCING FIELD: NORTH RANKIN GAS FIELD, NORTH WEST SHELF, AUSTRALIA

1992 ◽  
Vol 32 (1) ◽  
pp. 20
Author(s):  
L. Tilbury ◽  
T. Barter
Keyword(s):  
New Technology ◽  
Development Planning ◽  
Geological Structure ◽  
Lower Jurassic ◽  
Production Performance ◽  
Amplitude Analysis ◽  
Gas Field ◽  
North West ◽  
The North ◽  
Drilling Technology

New technology, especially the significant advances in 3D seismic interpretation techniques and drilling technology, has had a major impact on the development planning for the North Rankin Field.Significant advances have been made through the application of: horizon attribute processing, seismic amplitude analysis and long-reach drilling technology.Horizon attribute processing, including image processing techniques, has led to a better understanding of the structurally complex region on the northern flank of the field. These studies, coupled with new geological concepts related to opposing fault regimes, have concluded that good reservoir communication should exist across a fault zone previously thought to subdivide the field into compartments. The drilling of expensive, long-reach wells into the northern sector has thus been deferred, and may never be required, because of the newly developed structural model.Seismic amplitude analysis, coupled with geological modelling, upgraded the North Rankin West area and culminated in the recent significant appraisal/development well NRA22. This well was drilled from the North Rankin 'A' (NRA) platform to a target outside the main North Rankin Field in the adjacent Searipple Graben. NRA22 encountered well developed gas-bearing sands of Bathonian age which flowed at high rates (140 MMSCFGD).The application of long-reach drilling technology within Woodside has also had significant impact on development planning. The original development plan for North Rankin included a second platform in the northeast of the field. Better than expected production performance from NRA, related to across-fault reservoir communication, removed the necessity for a second platform. Large gas reserves in the Lower Jurassic 'NC' unit in the northeast have, however, required dedicated wells to improve ultimate recovery from this unit. The drilling of long-reach wells (at record drift) into the NC unit has provided better access to these reserves.Although North Rankin has been producing for over seven years with a total of 23 development wells drilled, understanding of the geological structure is still being improved by using new technology and ideas.

OFFSHORE PETROLEUM POTENTIAL IN NEW ZEALAND

1974 ◽  
Vol 14 (1) ◽  
pp. 3
Author(s):  
H. R. Katz
Keyword(s):  
New Zealand ◽  
Sedimentary Basins ◽  
The South ◽  
The West ◽  
Gas Field ◽  
Petroleum Potential ◽  
The North ◽  
Depth Contour ◽  
Tectonic Disturbances ◽  
Marine Seismic

Extensive shelves and intermediate-depth terraces, rises, and plateaus characterize the New Zealand offshore region. Sedimentary basins with hydrocarbon potential on land, which all have formed after the Early Cretaceous Rangitata Orogeny, are mainly lined up along the west and east of both islands and obviously extend out to sea. Sediment thickness generally increases offshore, while the tectonic disturbances become markedly less severe. Prospects therefore look favourable, and on this basis offshore concessions to a total of nearly 400,000 sq. miles were taken up, covering the area all around New Zealand to a depth of 1,000 m. Ten offshore wells to an average depth of 10,000 ft have been drilled, the second, third and fourth of which establishing a large gas field with an estimated 5 trillion cu. ft of gas, and the seventh being a non-commercial oil discovery (tested flow rate 600 b/d). Marine seismic surveys have been done over about 80,000 line miles. However, the results indicate that in many areas maximum subsidence during the Tertiary occurred relatively close to the present landmass, whereas farther away on submarine rises and plateaus the basement is very shallow or even exposed; also nearer to land some areas have little or no prospects. Consequently, 70,000 sq. miles have been relinquished-with only one well here drilled-and more acreage will probably be relinquished in the near future. But the overall potential still is encouraging; interesting prospects remain particularly along the west coast within the 500 m depth contour and extending from about 35° to 44°, also along the east coast of the North Island, on the eastern half of Chatham Rise, in the south -east of the South Island south of Christchurch and towards the central depression of Campbell Plateau, and in the head of Solander Trough. These areas amount to about 100,000 sq. miles. Concessions totalling 50,000 sq. miles (which for the greater part lie within the above areas) are in their second 5-year term and will expire on 30 September 1975; until then, more drilling is expected to outline existing prospects in greater detail. There is reasonable hope for further discoveries of substantial petroleum accumulations.

Terrestrial and Freshwater Invertebrate Fauna of the High Arctic Archipelago of Svalbard

Zootaxa ◽  
2007 ◽  
Vol 1448 (1) ◽  
pp. 41-68 ◽  
Author(s):  
STEPHEN JAMES COULSON
Keyword(s):  
West Coast ◽  
Primary Source ◽  
Sampling Bias ◽  
High Arctic ◽  
Invertebrate Fauna ◽  
The West ◽  
Additional Species ◽  
North East ◽  
The North ◽  
Freshwater Invertebrate

An overview of the terrestrial and freshwater invertebrate fauna of the High Arctic archipelago of Svalbard is presented. Sixty seven additional species to the previous checklist are listed and the described terrestrial and freshwater invertebrate fauna of Svalbard now stands at 1,107 species. Species presented are cross referenced to the literature.        A brief comparison with the invertebrate fauna of Greenland indicates that Svalbard may be under-represented in Hymenoptera, Hemiptera and Lepidoptera but over-represented in Collembola and Acari. However, since 82% of Svalbard primary source manuscripts originate from three locations along the west coast, there is a resulting likely bias in our knowledge of the invertebrate fauna. The west coast has a mild climate for the northerly latitude due to the influence of the West Spitsbergen Current, a northerly flowing branch of the North Atlantic Drift. The faunistically poorly known east coast is hypothesised to have a different invertebrate fauna due to the predominant winds and currents originating from the north east and hence this coast will have a different history of immigration and colonization from the west coast.        The use of checklists is therefore cautioned due to possible sampling bias and omissions created by a concentration of work on popular groups and at a limited number of localities. However, this does not detract from their importance as baseline databases, especially during a period of rapid environmental change

The Lower Jurassic Hanson Formation of the Transantarctic Mountains: implications for the Antarctic sector of the Gondwana plate margin

2016 ◽  
Vol 154 (4) ◽  
pp. 777-803 ◽  
Author(s):  
D.H. ELLIOT ◽  
D. LARSEN ◽  
C.M. FANNING ◽  
T.H. FLEMING ◽  
J. D. VERVOORT
Keyword(s):  
Lower Jurassic ◽  
Early Jurassic ◽  
Detrital Zircons ◽  
Coarse Grained ◽  
Large Igneous Province ◽  
Rift System ◽  
The West ◽  
West Antarctic ◽  
Plate Margin ◽  
Gondwana Margin

AbstractThe Hanson Formation, Antarctica, consists of interbedded sandstones and tuffaceous rocks of Early Jurassic age. The sandstones, pebbly to medium-grained, range between quartzo-feldspathic and volcaniclastic, with some of the former being coarse-grained arkoses that imply proximal sources. Geochronology of detrital zircons provides evidence for source rock ages, whereas sandstone petrology demonstrates a mixed provenance. Tuffaceous strata are reworked fine to very fine-grained tuffs resulting from distal Plinian eruptions. Dated tuffs provide time constraints on the duration of volcanism. The sandstones and tuffs accumulated in a rift environment. Geochemically the tuffs are rhyolitic in composition, and the Sr and Nd isotope data together with the patterns on multi-element diagrams suggest they were derived from a volcanic arc, which is interpreted to have been located along the West Antarctic Gondwana margin. The silicic volcanism extends the distribution and timing of magmatism in the Early Jurassic along that margin. The Early Jurassic extensional regime was delimited by the plate margin region and the East Antarctic craton. The rift valley system along the East Antarctic craton margin, in which the Hanson strata accumulated, was the focus for subsequent emplacement of the intrusive and extrusive rocks of the Lower Jurassic Ferrar Large Igneous Province. The Early Jurassic extensional rifts may have been reactivated during Cretaceous–Cenozoic development of the West Antarctic Rift System.

Mafias on the Move

2011 ◽  
Author(s):  
Federico Varese
Keyword(s):  
United States ◽  
New York ◽  
Organized Crime ◽  
The United States ◽  
The West ◽  
Market Expansion ◽  
The North ◽  
Economic Transformations ◽  
At Will

Organized crime is spreading like a global virus as mobs take advantage of open borders to establish local franchises at will. That at least is the fear, inspired by stories of Russian mobsters in New York, Chinese triads in London, and Italian mafias throughout the West. As this book explains, the truth is more complicated. The author has spent years researching mafia groups in Italy, Russia, the United States, and China, and argues that mafiosi often find themselves abroad against their will, rather than through a strategic plan to colonize new territories. Once there, they do not always succeed in establishing themselves. The book spells out the conditions that lead to their long-term success, namely sudden market expansion that is neither exploited by local rivals nor blocked by authorities. Ultimately the inability of the state to govern economic transformations gives mafias their opportunity. In a series of matched comparisons, the book charts the attempts of the Calabrese 'Ndrangheta to move to the north of Italy, and shows how the Sicilian mafia expanded to early twentieth-century New York, but failed around the same time to find a niche in Argentina. The book explains why the Russian mafia failed to penetrate Rome but succeeded in Hungary. A pioneering chapter on China examines the challenges that triads from Taiwan and Hong Kong find in branching out to the mainland. This book is both a compelling read and a sober assessment of the risks posed by globalization and immigration for the spread of mafias.

Rola Avarského Kaganátu Pri Vzniku Slovenčiny

2018 ◽  
Vol 69 (2) ◽  
pp. 199-236
Author(s):  
Martin Braxatoris ◽  
Michal Ondrejčík
Keyword(s):  
Slavic Language ◽  
The West ◽  
The North ◽  
Danube Region ◽  
The Absolute ◽  
North Edge ◽  
The Relationship ◽  
Slovak Language

Abstract The paper proposes a basis of theory with the aim of clarifying the casual nature of the relationship between the West Slavic and non-West Slavic Proto-Slavic base of the Slovak language. The paper links the absolute chronology of the Proto-Slavic language changes to historical and archaeological information about Slavs and Avars. The theory connects the ancient West Slavic core of the Proto-Slavic base of the Slovak language with Sclaveni, and non-West Slavic core with Antes, which are connected to the later population in the middle Danube region. It presumes emergence and further expansion of the Slavic koiné, originally based on the non-West Slavic dialects, with subsequent influence on language of the western Slavic tribes settled in the north edge of the Avar Khaganate. The paper also contains a periodization of particular language changes related to the situation in the Khaganate of that time.

The population of Red Deer (Cervus elaphus L., 1758) in Tulcea county (Romania)

2010 ◽  
Vol 53 (1) ◽  
pp. 351-356
Author(s):  
Sorin Geacu
Keyword(s):  
Cervus Elaphus ◽  
Red Deer ◽  
Forest Land ◽  
The West ◽  
Spreading Area ◽  
Deer Population ◽  
The North ◽  
Natural Expansion ◽  
North Western

The population of Red Deer (Cervus elaphus L., 1758) in Tulcea county (Romania) The presence of the Red Deer in the North-western parts of Tulcea County is an example of the natural expansion of a species spreading area. In North Dobrogea, this mammal first occurred only forty years ago. The first specimens were spotted on Cocoşul Hill (on the territory of Niculiţel area) in 1970. Peak numbers (68 individuals) were registered in the spring of 1987. The deer population (67 specimens in 2007) of this county extended along 10 km from West to East and 20 km from North to South over a total of 23,000 ha (55% of which was forest land) in the East of the Măcin Mountains and in the West of the Niculiţel Plateau.

US and Russian policies and strategies in the Middle East: Iraq and Syria as a model

2019 ◽  
pp. 220
Author(s):  
Esraa Aladdin Noori ◽  
Nasser Zain AlAbidine Ahmed
Keyword(s):  
Middle East ◽  
East Asia ◽  
Balance Of Power ◽  
Western World ◽  
International Conflicts ◽  
The South ◽  
The West ◽  
The North ◽  
East Region ◽  
Middle East Region

The Russian-American relations have undergone many stages of conflict and competition over cooperation that have left their mark on the international balance of power in the Middle East. The Iraqi and Syrian crises are a detailed development in the Middle East region. The Middle East region has allowed some regional and international conflicts to intensify, with the expansion of the geopolitical circle, which, if applied strategically to the Middle East region, covers the area between Afghanistan and East Asia, From the north to the Maghreb to the west and to the Sudan and the Greater Sahara to the south, its strategic importance will seem clear. It is the main lifeline of the Western world.

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