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Greg H. Browne - One of the best experts on this subject based on the ideXlab platform.
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provenance of the pakawau group and farewell formation late cretaceous paleocene taranaki basin Northwest Nelson new zealand
New Zealand Journal of Geology and Geophysics, 2020Co-Authors: Sarah L Smithies, Greg H. Browne, K N Bassett, Alexander R L NicholsAbstract:ABSTRACTPaleogeographic and tectonic models for the southern Taranaki Basin are refined with sandstone and conglomerate provenances determined from the Late Cretaceous fluvial Rakopi, marginal mari...
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Provenance of the Pakawau Group and Farewell Formation (Late Cretaceous – Paleocene), Taranaki Basin, Northwest Nelson, New Zealand
New Zealand Journal of Geology and Geophysics, 2019Co-Authors: Sarah L Smithies, Greg H. Browne, K N Bassett, Alexander R L NicholsAbstract:ABSTRACTPaleogeographic and tectonic models for the southern Taranaki Basin are refined with sandstone and conglomerate provenances determined from the Late Cretaceous fluvial Rakopi, marginal mari...
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Reservoir potential of Late Cretaceous terrestrial to shallow marine sandstones, Taranaki Basin, New Zealand
Marine and Petroleum Geology, 2010Co-Authors: K.e. Higgs, Greg H. Browne, Malcolm J Arnot, E.m. KennedyAbstract:Abstract Late Cretaceous coals and coaly source rocks are the main source of hydrocarbons in the Taranaki Basin, yet to date there have not been any hydrocarbon discoveries within Cretaceous strata, and sandstone distribution and reservoir quality for this interval have been poorly understood. The Late Cretaceous sediments were deposited in several sub-basins across Taranaki, with their distribution largely determined by sediment supply, subsidence, and sea level change. In this study, we describe potential reservoir facies in well penetrations of Cretaceous strata in Taranaki, as well as from outcrop in Northwest Nelson, on the southern edge of the basin. Study of Cretaceous outcrop has shown that facies distribution is a major control on reservoir quality. Shoreface, intertidal, and estuarine depositional facies contain both excellent, well sorted sandstone reservoir facies as well as low net-to-gross, reservoir-poor facies. These contrast with deposits from generally less well sorted, and more heterolithic coastal plain environments. Much of the facies distribution is attributed to relative sea level fluctuations, which occurred throughout deposition. Late Cretaceous sandstones display a range of mean grain sizes and compositions, with the latter related to geographic location and sediment source. Burial depths are highly variable across the basin, ranging from 6 km, and this has had a profound effect on reservoir quality. The main petrographic controls on reservoir quality are sandstone composition, volume of clay minerals, degree of mechanical compaction (related to maximum burial depth), and proximity to a source of acidic pore fluids for the generation of secondary porosity. Results from this study suggest that Cretaceous strata are a viable reservoir play over much of the western part of the Taranaki Basin and into parts of the south-eastern basin. Palaeogeographic maps and textural/compositional data can be used to high-grade regions for further exploration.
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first new zealand record of probable dinosaur footprints from the late cretaceous north cape formation Northwest Nelson
New Zealand Journal of Geology and Geophysics, 2009Co-Authors: Greg H. BrowneAbstract:Abstract Structures that are interpreted as dinosaur footprints are recorded from six localities within the Late Cretaceous (Maastrictian) aged North Cape Formation of Northwest Nelson. These are the first dinosaur footprints to be recognised from New Zealand and the first occurrence of dinosaurs from the South Island, and add considerably to our knowledge of New Zealand dinosaurs, which currently is based on only three dinosaur bone fossil localities. The trace fossils occur within sandstone beds that form part of a succession of intertidal sandstones and mudstones. In cross‐section, the footprints form structures with sharp vertical margins, infilled with both massive or laminated sandstone and discrete blocks of sandstone and mudstone. Sediments underlying are either planar with the base of the structures or deformed downward, and overlying sediments drape into the tops of the structures. In plan view, structures are usually roughly circular, with clear margins, and are filled with both blocky and mass...
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An outcrop‐based study of the economically significant Late Cretaceous Rakopi Formation, Northwest Nelson, Taranaki Basin, New Zealand
New Zealand Journal of Geology and Geophysics, 2008Co-Authors: Greg H. Browne, Elizabeth M. Kennedy, Rosalie M. Constable, Erica M. Crouch, J. Ian Raine, Richard SykesAbstract:Abstract The Late Cretaceous Rakopi Formation (Pakawau Group) represents one of the most important petroleum source rock units and a potential reservoir unit in the highly prospective Taranaki Basin. This paper presents a predominantly outcrop‐based study of the sedimentology, petrography, stratigraphy, and depositional environment of the Rakopi Formation in the Paturau River and Pakawau areas of Northwest Nelson, southern Taranaki Basin, together with some preliminary insights into the stratigraphie architecture of the Pakawau Group on a more basin‐wide scale. The Rakopi Formation is interpreted here as a terrestrial deposit, representing sedimentation in fluvial channels and their associated overbank and levee environments. However, the presence of dinoflagellates, glauconite, and elevated coal seam sulfur contents is evidence for periodic marine influence during deposition. This could be explained by a low‐gradient coastal plain paleogeography, crossed by a series of rivers and their associated floodpl...
D W Lewis - One of the best experts on this subject based on the ideXlab platform.
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a cretaceous early tertiary macrotidal estuarine fluvial succession puponga coal measures in whanganui inlet onshore pakawau sub basin Northwest Nelson new zealand
New Zealand Journal of Geology and Geophysics, 1994Co-Authors: D W LewisAbstract:Abstract Detailed lithofacies analysis of the Puponga Coal Measures Member along the western shore of the Whanganui Inlet, Northwest Nelson, is based on five measured sections i hat incorporate parts of the interfingering and underlying North Cape Formation and overlying Farewell Formation. Two contrasting depositional systems, lithofacies Association A and B, are recognised on the basis of sedimentary structures, textures, paleocurrent data, and the local presence of coal and dinoflagellates. Association A1–3, North Cape Formation, which includes the Puponga Coal Measures Member (Haumurian ‐ Lower Teurian), represents a progradational sequence of estuarine, fluvial, floodplain, and mire deposits. Sub‐environments include: high energy subtidal channels, upper‐flow regime subtidal to intertidal sand shoals or flats, intertidal mixed sand/mud and mud flats, salt marsh, mires, fluvial distributary or crevasse channels and levees, and open/closed bays. The overall setting is a macrotidal estuary over which mi...
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A cretaceous ‐ early tertiary Macrotidal estuarine‐fluvial succession: Puponga coal measures in Whanganui inlet, onshore Pakawau sub‐basin, Northwest Nelson, New Zealand
New Zealand Journal of Geology and Geophysics, 1994Co-Authors: D W LewisAbstract:Abstract Detailed lithofacies analysis of the Puponga Coal Measures Member along the western shore of the Whanganui Inlet, Northwest Nelson, is based on five measured sections i hat incorporate parts of the interfingering and underlying North Cape Formation and overlying Farewell Formation. Two contrasting depositional systems, lithofacies Association A and B, are recognised on the basis of sedimentary structures, textures, paleocurrent data, and the local presence of coal and dinoflagellates. Association A1–3, North Cape Formation, which includes the Puponga Coal Measures Member (Haumurian ‐ Lower Teurian), represents a progradational sequence of estuarine, fluvial, floodplain, and mire deposits. Sub‐environments include: high energy subtidal channels, upper‐flow regime subtidal to intertidal sand shoals or flats, intertidal mixed sand/mud and mud flats, salt marsh, mires, fluvial distributary or crevasse channels and levees, and open/closed bays. The overall setting is a macrotidal estuary over which mi...
Elizabeth M. Kennedy - One of the best experts on this subject based on the ideXlab platform.
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An outcrop‐based study of the economically significant Late Cretaceous Rakopi Formation, Northwest Nelson, Taranaki Basin, New Zealand
New Zealand Journal of Geology and Geophysics, 2008Co-Authors: Greg H. Browne, Elizabeth M. Kennedy, Rosalie M. Constable, Erica M. Crouch, J. Ian Raine, Richard SykesAbstract:Abstract The Late Cretaceous Rakopi Formation (Pakawau Group) represents one of the most important petroleum source rock units and a potential reservoir unit in the highly prospective Taranaki Basin. This paper presents a predominantly outcrop‐based study of the sedimentology, petrography, stratigraphy, and depositional environment of the Rakopi Formation in the Paturau River and Pakawau areas of Northwest Nelson, southern Taranaki Basin, together with some preliminary insights into the stratigraphie architecture of the Pakawau Group on a more basin‐wide scale. The Rakopi Formation is interpreted here as a terrestrial deposit, representing sedimentation in fluvial channels and their associated overbank and levee environments. However, the presence of dinoflagellates, glauconite, and elevated coal seam sulfur contents is evidence for periodic marine influence during deposition. This could be explained by a low‐gradient coastal plain paleogeography, crossed by a series of rivers and their associated floodpl...
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an outcrop based study of the economically significant late cretaceous rakopi formation Northwest Nelson taranaki basin new zealand
New Zealand Journal of Geology and Geophysics, 2008Co-Authors: Greg H. Browne, Elizabeth M. Kennedy, Rosalie M. Constable, Erica M. Crouch, Ian J Raine, Richard SykesAbstract:Abstract The Late Cretaceous Rakopi Formation (Pakawau Group) represents one of the most important petroleum source rock units and a potential reservoir unit in the highly prospective Taranaki Basin. This paper presents a predominantly outcrop‐based study of the sedimentology, petrography, stratigraphy, and depositional environment of the Rakopi Formation in the Paturau River and Pakawau areas of Northwest Nelson, southern Taranaki Basin, together with some preliminary insights into the stratigraphie architecture of the Pakawau Group on a more basin‐wide scale. The Rakopi Formation is interpreted here as a terrestrial deposit, representing sedimentation in fluvial channels and their associated overbank and levee environments. However, the presence of dinoflagellates, glauconite, and elevated coal seam sulfur contents is evidence for periodic marine influence during deposition. This could be explained by a low‐gradient coastal plain paleogeography, crossed by a series of rivers and their associated floodpl...
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Discovery of a Cretaceous angiosperm reproductive structure from New Zealand
New Zealand Journal of Geology and Geophysics, 2003Co-Authors: Elizabeth M. Kennedy, John D. Lovis, Ian L. DanielAbstract:Abstract Angiosperm reproductive structure macrofossils have been discovered in Late Cretaceous rocks from Northwest Nelson, South Island, New Zealand. We have collected over 100 specimens of the same form, of striking stellate appearance, from a locality of late Campanian or Maastrichtian age. These are the first such fossils of Cretaceous age reported from New Zealand.
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Late Cretaceous and Paleocene terrestrial climates of New Zealand: Leaf fossil evidence from South Island assemblages
New Zealand Journal of Geology and Geophysics, 2003Co-Authors: Elizabeth M. KennedyAbstract:Abstract Univariate and multivariate leaf morphology‐based analysis of leaf fossil assemblages from localities in the South Island of New Zealand provide quantitative paleoclimate estimates for the terrestrial Late Cretaceous and Paleocene. Favourable growing conditions with a cool to mild temperate climate are inferred for the youngest pollen zone in the Late Cretaceous (PM2) with moderately high precipitation and high dicotyledonous angiosperm diversity. Mean annual temperature estimates of c. 12–16 and c. 7–11°C were produced from Northwest Nelson and North Otago PM2 Zone assemblages, respectively. These different temperature estimates most likely reflect differences in age, although geographic differences may also be a factor. Consistent data from three Paleocene assemblages suggest cool‐temperate conditions. Mean annual temperature estimates of c. 6–12°C were produced from these Paleocene assemblages. They also had lower dicotyledonous leaf diversity than the Late Cretaceous assemblages, no more than...
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Quantitative palaeoclimate estimates from Late Cretaceous and Paleocene leaf floras in the Northwest of the South Island, New Zealand
Palaeogeography Palaeoclimatology Palaeoecology, 2002Co-Authors: Elizabeth M. Kennedy, Robert A. Spicer, Peter Mca. ReesAbstract:Three new plant macrofossil assemblages were collected from Late Cretaceous and Paleocene fluvio-lacustrine sediments of the Pakawau and Kapuni groups in the Northwest of the South Island, New Zealand. Palaeoenvironmental interpretations were made from each locality and palaeoclimate was deduced from the dicotyledonous angiosperm leaf component of each flora. A latest Cretaceous (Pakawau Bush Road locality) flora yielded 58 different dicotyledonous leaf forms; the two Paleocene collections, Ian's Tip and Pillar Point Track, included 23 and 28 dicotyledonous leaf forms respectively. Quantitative palaeoclimate estimates were obtained using both Leaf Margin Analysis (LMA) and the Climate Leaf Analysis Multivariate Program (CLAMP). Temperature estimates suggest that there was a slight cooling from the latest Cretaceous into the early Paleocene in the Northwest Nelson region of New Zealand, supporting similar Southern Hemisphere palaeoclimate findings from Antarctic data. Consistency in temperature estimates using different methods, including LMA, multivariate leaf morphological analysis (CLAMP), oxygen isotope data, regional versus local studies and global palaeoclimate models, suggests that the mean annual temperature for the Pakawau region in the latest Cretaceous was between 12 and 15°C. LMA produced temperature estimates between 6.5 and 8°C for the two Paleocene assemblages whereas CLAMP-produced estimates were slightly higher between 9 and 12.5°C © 2002 Elsevier Science B.V. All rights reserved.
Richard Sykes - One of the best experts on this subject based on the ideXlab platform.
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An outcrop‐based study of the economically significant Late Cretaceous Rakopi Formation, Northwest Nelson, Taranaki Basin, New Zealand
New Zealand Journal of Geology and Geophysics, 2008Co-Authors: Greg H. Browne, Elizabeth M. Kennedy, Rosalie M. Constable, Erica M. Crouch, J. Ian Raine, Richard SykesAbstract:Abstract The Late Cretaceous Rakopi Formation (Pakawau Group) represents one of the most important petroleum source rock units and a potential reservoir unit in the highly prospective Taranaki Basin. This paper presents a predominantly outcrop‐based study of the sedimentology, petrography, stratigraphy, and depositional environment of the Rakopi Formation in the Paturau River and Pakawau areas of Northwest Nelson, southern Taranaki Basin, together with some preliminary insights into the stratigraphie architecture of the Pakawau Group on a more basin‐wide scale. The Rakopi Formation is interpreted here as a terrestrial deposit, representing sedimentation in fluvial channels and their associated overbank and levee environments. However, the presence of dinoflagellates, glauconite, and elevated coal seam sulfur contents is evidence for periodic marine influence during deposition. This could be explained by a low‐gradient coastal plain paleogeography, crossed by a series of rivers and their associated floodpl...
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an outcrop based study of the economically significant late cretaceous rakopi formation Northwest Nelson taranaki basin new zealand
New Zealand Journal of Geology and Geophysics, 2008Co-Authors: Greg H. Browne, Elizabeth M. Kennedy, Rosalie M. Constable, Erica M. Crouch, Ian J Raine, Richard SykesAbstract:Abstract The Late Cretaceous Rakopi Formation (Pakawau Group) represents one of the most important petroleum source rock units and a potential reservoir unit in the highly prospective Taranaki Basin. This paper presents a predominantly outcrop‐based study of the sedimentology, petrography, stratigraphy, and depositional environment of the Rakopi Formation in the Paturau River and Pakawau areas of Northwest Nelson, southern Taranaki Basin, together with some preliminary insights into the stratigraphie architecture of the Pakawau Group on a more basin‐wide scale. The Rakopi Formation is interpreted here as a terrestrial deposit, representing sedimentation in fluvial channels and their associated overbank and levee environments. However, the presence of dinoflagellates, glauconite, and elevated coal seam sulfur contents is evidence for periodic marine influence during deposition. This could be explained by a low‐gradient coastal plain paleogeography, crossed by a series of rivers and their associated floodpl...
Alexander R L Nichols - One of the best experts on this subject based on the ideXlab platform.
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provenance of the pakawau group and farewell formation late cretaceous paleocene taranaki basin Northwest Nelson new zealand
New Zealand Journal of Geology and Geophysics, 2020Co-Authors: Sarah L Smithies, Greg H. Browne, K N Bassett, Alexander R L NicholsAbstract:ABSTRACTPaleogeographic and tectonic models for the southern Taranaki Basin are refined with sandstone and conglomerate provenances determined from the Late Cretaceous fluvial Rakopi, marginal mari...
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Provenance of the Pakawau Group and Farewell Formation (Late Cretaceous – Paleocene), Taranaki Basin, Northwest Nelson, New Zealand
New Zealand Journal of Geology and Geophysics, 2019Co-Authors: Sarah L Smithies, Greg H. Browne, K N Bassett, Alexander R L NicholsAbstract:ABSTRACTPaleogeographic and tectonic models for the southern Taranaki Basin are refined with sandstone and conglomerate provenances determined from the Late Cretaceous fluvial Rakopi, marginal mari...