Chris Uruski

OMV New Zealand · Exploration

The stratigraphic architecture of a thick (c. 9000 m) Albian–Recent sedimentary succession within the Pegasus Basin is presented here, based primarily on interpretation of the New Zealand Government's ‘PEG09’ 2D reconnaissance seismic survey. The basin lies immediately east and outboard of the Hikurangi subduction zone, and formed mainly because of...

Reconnaissance 2D seismic reflection data intended to investigate the petroleum potential of New Zealand's marine territories have contributed many insights into the geological evolution of the large continental block that surrounds New Zealand. These include: definition of a back-thrust system to the Mesozoic Gondwana subduction margin along the N...

Field, B., Baur, J., Bland, K., Browne, G., Griffin, A., Ilg, B., Juniper, Z., Lawrence, M., Marrett, R., Mildren, S., Milner, M., Morgans, H., Roncaglia, L., Uruski, C., Zhu H. 2011. Geological Transect Across the Wairoa Area: Insights into elements of the East Coast petroleum system. GNS Science Data Series 11a. (Sesiware, TrapTester, 2DMove, sei...

The islands of New Zealand cover an area of approximately 250,000 km2, but the New Zealand Exclusive Economic Zone (EEZ) extends to around 4 million km2 and recent confirmation of New Zealand’s Extended Continental Shelf (ECS) has added a further 1.7 million km2 to the country’s marine estate. Within the 5.7 million km2 of New Zealand’s marine terr...

We use seismic reflection and rock sample data to propose that the first-order physiography of New Caledonia Trough and Norfolk Ridge formed in Eocene and Oligocene time and was associated with the onset of subduction and back-arc spreading at the Australia-Pacific plate boundary. Our tectonic model involves an initial Cretaceous rift that is stron...

Schioler, P.; Rogers, K.M.; Sykes, R.; Hollis, C.J.; Ilg, B.R.; Meadows, D.; Roncaglia, L.; Uruski, C.I. 2010 Palynofacies, organic geochemistry and depositional environment of the Tartan Formation (Late Paleocene), a potential source rock in the Great South Basin, New Zealand. Marine and Petroleum Geology, 27(2): 351-369; 1. Detailed palynofacies...

Uruski, C.I.; Reid, E.; Stagpoole, V.M.; Herzer, R.H.; Griffin, A.G.; Bland, K.J.; Ilg, B.R.; Browne, G.H. 2010 The Reinga Basin, North Island, New Zealand. APPEA Journal, 50: 287-308.

We use seismic-reflection and rock-sample data to propose that the first-order physiography of New Caledonia Trough and Norfolk Ridge formed in Eocene and Oligocene time, and was associated with the onset of subduction at the Australia-Pacific plate boundary. Lithosphere delamination and subduction initiation was followed by rapid rollback of the s...

We use seismic reflection and refraction data to determine crustal structure, to map a fore-arc basin containing 12 km of sediment, and to image the subduction thrust at 35 km depth. Seismic reflection megasequences within the basin are correlated with onshore geology: megasequence X, Late Cretaceous and Paleogene marine passive margin sediments; m...

Field, B.D.; Baur, J.R.; Bland, K.J.; Browne, G.H.; Griffin, A.G.; Ilg, B.R.; Juniper, Z.; Lawrence, M.J.F.; Marrett, R.; Mildren, S.; Milner, M.; Morgans, H.E.G.; Roncaglia, L.; Uruski, C.I.; Zhu, H. 2009 Tectonostratigraphic development and hydrocarbon reservoir quality on a convergent margin : East Coast, North Island, New Zealand. APPEA Journal...

The paper discusses the results from the GA–302 2D seismic survey and GA–2436 (RV Tangaroa) marine reconnaissance survey over the Capel and Faust basins in the northern Tasman Sea. The integration of seismic, potential field and bathymetric data sets in 3D space at an early stage in the project workflow has assisted in the visualisation of the basi...

Stagpoole, V.M.; Reid, E.; Browne, G.H.; Bland, K.J.; Ilg, B.R.; Griffin, A.G.; Herzer, R.H.; Uruski, C.I. 2009 Petroleum prospectivity of Reinga Basin, New Zealand. GNS Science Consultancy Report 2009/251. 105 p. (Seisware 2D seismic interpretation and incorporation of 1D basin modelling, swath bathymetry, NPA satellite seep analysis, tide history...

New seismic reflection and refraction data from northern New Zealand allow us to determine crustal thickness, map a forearc basin containing 12 km of sediment, and image the subduction thrust at 30-40 km depth. The Moho lies at 18 km beneath the basin centre, and at 35 km at the southern margin. Raukumara Basin is uplifted along its eastern and sou...

Deepwater Taranaki is investigated for its petroleum potential, using all available seismic data tied to shallow-water wells. It contains up to 10 km of sediment. An early rift sequence is overlain by a large Late Cretaceous delta, which culminates with the mid-Campanian Rakopi Formation coal measures. This sequence marks the break-up unconformity...

Ilg, B.R.; Uruski, C.I. 2008 Structural modelling of interpreted DUN06 seismic data from offshore Great South Basin. 1 poster In: 2008 New Zealand Petroleum Conference proceedings: beyond 08. Wellington: Ministry of Economic Development.

Deformation across the active Hikurangi subduction margin, New Zealand, including shortening, extension, vertical-axis rotations, and strike-slip faulting in the upper plate, has been estimated for the last ~24 Myr using margin-normal seismic reflection lines and cross sections, strike-slip fault displacements, paleomagnetic declinations, bending o...

Much of the Great South Basin is covered by a 30,000 km grid of old seismic data, dating from the 1970s. This early exploration activity resulted in drilling eight wells, one of which, Kawau–1a, was a 461 Bcf gas-condensate discovery. Three other wells had significant oil and gas shows; in particular, Toroa–1 had extensive gas shows and 300 m oil s...

Seismic reflection data from the subduction margin off the east coast of the North Island, New Zealand, show first-order structural features in the upper plate and subducting slab geometry that we relate to plate coupling at the subduction interface. Beneath the eastern coastline of North Island, New Zealand, the subducted Pacific plate dips at les...

GNS Science has recently started a 4 year government-funded project to develop an atlas describing the geologic architecture of the Taranaki Basin, New Zealand. Approximately 20-30 horizons will be interpreted on digital seismic data and depth converted to provide structural and seismic facies maps. This integrated approach utilizing high resolutio...

We analyse results of dredge sampling, a high‐resolution seismic reflection survey, and unpublished petroleum industry data from part of the overriding continental plate of the Fiordland subduction zone. Plate tectonic calculations show that convergence rates have progressively increased since Miocene time, when subduction‐related processes started...

Uruski, C.I.; Ilg, B.R. 2006 Preliminary interpretation and structural modelling of DUN06 seismic reflection data from Great South Basin, offshore New Zealand. GNS Science Consultancy Report 2006/233. iii, 46 p. (Seisware, GeoFrame import, 2DMove, well log, paleogeography, microfossil Petrel, Seisware, TrapTester, 2DMove seismic interpretation and...

Beneath the eastern coastline of North Island, New Zealand, the subducted Pacific plate dips at less than 3 degrees to the northwest and the subduction decollement is at a depth of less than 15-km. The active-source NIGHT and passive-source CNIPSE experiments carried out in 2001 image the shallow dipping decollement down to more than 6 s (twt) at w...

Oil production in the East Coast Basin began in the late 19th century from wildcat wells near oil seeps. By the mid-20th century, geology was being applied to oil exploration, but with little success. In the late 20th century, seismic techniques were added to the exploration arsenal and several gas discoveries were made. At each stage it was recogn...

Understanding the genesis and habitat of hydrocarbons in a sedimentary basin takes knowledge of that basin at many levels, from basic infill geology to petroleum systems, plays, prospects and detailed sequence stratigraphy. While geophysics can define the basins and their internal structures, biostratigraphy and paleogeography provide greater under...

More than 300 oil and gas seeps are known in the onshore East Coast Basin of North Island, New Zealand. Spectacular geological structures have been explored by more than 40 wells, only three of which have been offshore. Results are tantalising, with 70% of wells yielding oil or gas shows. Westech’s two gas discoveries onshore at Kauhauroa and Tuhar...

The 6,200 km Astrolabe non-exclusive 2D seismic survey, acquired during 2001 over the deepwater extension of the Taranaki Basin from the shelf-edge to the 2,000 m isobath, revealed a Cretaceous section, thicker and probably older than any previously known from the Taranaki Basin. Sequence analysis shows that a major deltaic system, comparable to th...

Conoco (now Conoco-Phillips) relinquished PEP 38 602 on 1 April 2003 after acquiring 7000 km of high fold seismic data and drilling two wells, Wakanui-1 and Karewa-1. Wakanui-1 set a record for deep-water drilling in New Zealand, being drilled in just less than 1500 m of water. Although this well was dry, it encountered Jurassic coal measures simil...

A paradigm of New Zealand petroleum geology was that the oldest source rocks known in the region were of Cretaceous age, so any older sedimentary rocks were considered to be economic basement. Two major projects have revealed that this is not universally the case and that a Jurassic petroleum system should now be considered. Firstly, the Astrolabe...

Bottom simulating reflectors (BSRs) represent the base of a gas hydrate zone underlain by widespread free gas. The extent of BSRs (>40,000 km2) has been mapped on the continental slope of the Hikurangi margin using industry and research seismic data. A conductive model was used to calculate heat flow from the depth of the BSR to the surface. A regi...

Exploration of the Taranaki Basin entered a new phase in 2001 with Astrolabe, a 6,200 km high-quality 2D seismic survey acquired by TGS-NOPEC that has outlined a large depocentre containing up to 10 km of sedimentary fill. This new data has extended the previously-known Taranaki Basin into deeper water beyond the shelf edge. Subsequently, the New Z...

The results of a 2D seismic survey over the deepwater Taranaki basin in New Zealand are discussed. The survey showed that the basin is a Cretaceous play. The Astrolabe survey showed the presence of thick sedimentary successions. The basal unit of the Cretaceous section was a mounded unit. Two possible petroleum systems were postulated: the Late Cre...

Acquisition of new data has enhanced knowledge of New Zealand's deepawater areas to the point that a preliminary appraisal of the petroleum potential can now be made for some frontier basins. Interpretation of existing data suggests that the prerequisites for petroleum expulsion and entrapment occur in some frontier basins and there is potential fo...

The East Coast region is an area ofabout 75 000 km2, about half of which is offshore, extending from East Cape in the northeast to Kaikoura in the southwest, a distance of more than 500 km. The region straddles the active Hikurangi subduction margin between the Australian and Pacific plates. The stratigraphic succession consists of three elements:...

The southern Kermadec-Hikurangi convergent margin, east of New Zealand, accommodates the oblique subduction of the oceanic Hikurangi Plateau at rates of 4 5 cm/yr. Swath bathymetry and sidescan data, together with seismic reflection and geopotential data obtained during the GEODYNZ-SUD cruise, showed major changes in tectonic style along the margin...

Des données de cartographie EM12D et de géophysique récoltées pendant la campagne GEODYNZ-SUD Leg 1 sur la marge Kermadec-Hikurangi révèlent la tectogenèse associée au passage de la subduction intra-océanique oblique à la subduction sous-continentale très oblique, puis à la transgression intra-continentale. Le partitionnement des composantes décroc...

Note présentée par Jean Aubouin et article rédigé par l'équipe scientifique ORSTOM

The New Caledonia Basin is a major bathymetric trough extending north-westwards from Taranaki and continuing past New Caledonia. This paper is concerned with the 250 km of the feature closest to New Zealand and adjacent to the Taranaki Shelf. The New Caledonia Basin appears to have formed as the surface expression of a failed rift system. Gravity m...

The New Caledonia Basin is a major bathymetric feature extending northwest from Taranaki, New Zealand, between the Challenger Plateau/Lord Howe Rise and the Norfolk Ridge. Interpretations of gravity data and seismic refraction velocities indicate that crustal thinning did not proceed to formation of ocean crust. Rifting was pre-Cenozoic, and may be...

Magnetic, gravity, and seismic reflection data on the East Greenland continental margin were collected. The data were used to model the ocean-continent transition, and to study the nature and distribution of dipping, subacoustic basement (sub B) seismic reflector sequences. Post-reflector B sediments and the structure of the region are discussed.

The 6200 km Astrolabe non-exclusive 2D seismic survey was acquired during 2001 over the deepwater extension of the Taranaki Basin from the shelf-edge to the 2000m isobath. That survey revealed a Cretaceous section, thicker, and probably older than any previously known from the Taranaki Basin. Sequence analysis shows that a major deltaic system, com...

A 3,400 km 2D seismic survey, DTB08, was acquired by the PEP 38451 partners; Global Resource Holdings, LLLP, Hyundai HYSCO Ltd and AWE, across large areas of the permit in late 2008 and early 2009. This data set was integrated with the earlier 6,100 km acquired by TGS-NOPEC in 2001 to refine the interpretation across three large prospects that had...