title: Late Miocene – Early Pleistocene paleogeography of the onshore central Hawke’s Bay sector of the forearc basin, eastern North Island, New Zealand, and some implications for hydrocarbon prospectivity

authors: Bland, Kyle J.

subjects: paleogeography

abstract: The timing of trap formation in relation to the timing of source rock burial and maturation are important considerations in evaluating the hydrocarbon prospectivity of onshore parts of the forearc basin in central Hawke’s Bay.  We describe here aspects of the Late Miocene to Early Pleistocene paleogeography for the area based on detailed field mapping and lithofacies analysis, to help constrain petroleum systems evaluations.  Key conclusions are: 
•	Most deformation of the forearc basin fill appears to be relatively young (i.e. post-2 Ma).  This deformation has occurred after a major phase of Late Miocene to Pliocene sediment accumulation, and is particularly significant along the northwestern and southeastern margins of the basin.
•	The axis of the forearc basin in central Hawke’s Bay appears to have undergone little structural deformation.  Gentle force and reverse faults in the subsurface may be suitable traps.
•	The most widespread potential reservoir beds are Miocene sandstone beds.
•	Potential hydrocarbon source rocks are mostly absent from western parts of the basin due to significant Neogene uplift and erosion.  They are, however, probably still widely preserved beneath central parts of the basin where uplift and erosion have been much less pronounced.
•	Miocene structures within the axis of the basin, buried by the Late Miocene to Pleistocene siliciclastic succession, are likely exploration targets.

The forearc basin has been substantially inverted along its western side since the latest Pliocene, resulting in erosion of older sediments, including potential source rocks, down to basement in ranges flanking its western side.  The stratigraphy along the eastern margin of the forearc basin, and particularly the outcrop pattern of westward-younging Plio-Pleistocene limestones, records the development of faulting and folding associated with the elevation and growth of the inboard part of the accretionary wedge.  Parts of the forearc basin succession have become involved in the accretionary wedge, which has migrated westward through time.  
Uplift of the inboard margin of the accretionary wedge since the latest Miocene helped to cause an interior seaway to develop to the west during the Pliocene.  Distinctive coarse-grained bioclastic carbonate sediments of the Te Aute lithofacies were deposited along both margins of the seaway, which was most extensive during the Late Pliocene (Mangapanian).  Although significant volumes of siliciclastic sediment were supplied to the basin during the Pliocene, strong tidal currents periodically swept much of these sediments northeastward.  Tidal connections existed during the Pliocene into Wanganui Basin in the vicinity of Kuripapango and Manawatu Gorge.  By the latest Pliocene (lower Nukumaruan), the interior seaway became closed in the south with uplift of the Mount Bruce block in northern Wairarapa.
Potential reservoirs within the map area include both shelf and redeposited sandstone beds in the Miocene to Early Pliocene Tolaga Group.  Thick, coarse-grained, variably cemented Plio-Pleistocene limestone lithofacies in the Mangaheia Group are widespread along the margins of the basin, and have been the targets for several past exploration programmes.  However, drilling has shown that the attractiveness of the Pliocene limestone facies as reservoir beds is limited because they quickly pass laterally into siliciclastic mudstone away from the margins of the basin.

text: Late Miocene – Early Pleistocene paleogeography of the onshore central Hawke’s Bay sector of the forearc basin, eastern North Island, New Zealand, and some implications for hydrocarbon prospectivity The timing of trap formation in relation to the timing of source rock burial and maturation are important considerations in evaluating the hydrocarbon prospectivity of onshore parts of the forearc basin in central Hawke’s Bay.  We describe here aspects of the Late Miocene to Early Pleistocene paleogeography for the area based on detailed field mapping and lithofacies analysis, to help constrain petroleum systems evaluations.  Key conclusions are: 
•	Most deformation of the forearc basin fill appears to be relatively young (i.e. post-2 Ma).  This deformation has occurred after a major phase of Late Miocene to Pliocene sediment accumulation, and is particularly significant along the northwestern and southeastern margins of the basin.
•	The axis of the forearc basin in central Hawke’s Bay appears to have undergone little structural deformation.  Gentle force and reverse faults in the subsurface may be suitable traps.
•	The most widespread potential reservoir beds are Miocene sandstone beds.
•	Potential hydrocarbon source rocks are mostly absent from western parts of the basin due to significant Neogene uplift and erosion.  They are, however, probably still widely preserved beneath central parts of the basin where uplift and erosion have been much less pronounced.
•	Miocene structures within the axis of the basin, buried by the Late Miocene to Pleistocene siliciclastic succession, are likely exploration targets.

The forearc basin has been substantially inverted along its western side since the latest Pliocene, resulting in erosion of older sediments, including potential source rocks, down to basement in ranges flanking its western side.  The stratigraphy along the eastern margin of the forearc basin, and particularly the outcrop pattern of westward-younging Plio-Pleistocene limestones, records the development of faulting and folding associated with the elevation and growth of the inboard part of the accretionary wedge.  Parts of the forearc basin succession have become involved in the accretionary wedge, which has migrated westward through time.  
Uplift of the inboard margin of the accretionary wedge since the latest Miocene helped to cause an interior seaway to develop to the west during the Pliocene.  Distinctive coarse-grained bioclastic carbonate sediments of the Te Aute lithofacies were deposited along both margins of the seaway, which was most extensive during the Late Pliocene (Mangapanian).  Although significant volumes of siliciclastic sediment were supplied to the basin during the Pliocene, strong tidal currents periodically swept much of these sediments northeastward.  Tidal connections existed during the Pliocene into Wanganui Basin in the vicinity of Kuripapango and Manawatu Gorge.  By the latest Pliocene (lower Nukumaruan), the interior seaway became closed in the south with uplift of the Mount Bruce block in northern Wairarapa.
Potential reservoirs within the map area include both shelf and redeposited sandstone beds in the Miocene to Early Pliocene Tolaga Group.  Thick, coarse-grained, variably cemented Plio-Pleistocene limestone lithofacies in the Mangaheia Group are widespread along the margins of the basin, and have been the targets for several past exploration programmes.  However, drilling has shown that the attractiveness of the Pliocene limestone facies as reservoir beds is limited because they quickly pass laterally into siliciclastic mudstone away from the margins of the basin.

year: 2008

title: The Effect of Heat Treatment on the Structure and Properties of Hemp/PLA Composites

authors: Jayaraman, Jeevan

subjects: PLA

abstract: This project focuses on bio-derived composites made from poly(lactic acid) (PLA) and hemp as well as the influence of PLA crystallinity on material properties. 
It is known that crystallinity can occur as spherulites within a polymer matrix bulk and as transcrystallinity on fibre surfaces in thermoplastic matrix composites. In addition, thermal history is known to influence the degree of crystallinity of polymer materials. The aim of this project was to study the effect of heat treatment or  annealing  on crystallinity and the influence of this on properties of hemp/PLA composites. 
	Composites were observed to become more opaque during heat treatment and increased crystallinity after heat treatment was seen using optical microscopy. XRD and DSC results showed that crystallinity was much higher for composites than PLA, supporting the fibre acting as a nucleating agent. There was no apparent change to tensile strength with increased heat treatment for PLA, however, for composite samples, increased heat treatment led to a small reduction in average tensile strength. Although there was no discernable trend for change of fracture toughness with increased crystallinity for PLA, it decreased for composite materials. It appears that the increased crystallinity present in the composite in combination with increased stress concentration due to the presence of fibres is reducing composite toughness as well as leading to premature failure in tensile tests due to PLA brittleness explaining lower strengths for composites. DMTA suggests that increase in crystallinity contributes to thermal stability of the composite.

text: The Effect of Heat Treatment on the Structure and Properties of Hemp/PLA Composites This project focuses on bio-derived composites made from poly(lactic acid) (PLA) and hemp as well as the influence of PLA crystallinity on material properties. 
It is known that crystallinity can occur as spherulites within a polymer matrix bulk and as transcrystallinity on fibre surfaces in thermoplastic matrix composites. In addition, thermal history is known to influence the degree of crystallinity of polymer materials. The aim of this project was to study the effect of heat treatment or  annealing  on crystallinity and the influence of this on properties of hemp/PLA composites. 
	Composites were observed to become more opaque during heat treatment and increased crystallinity after heat treatment was seen using optical microscopy. XRD and DSC results showed that crystallinity was much higher for composites than PLA, supporting the fibre acting as a nucleating agent. There was no apparent change to tensile strength with increased heat treatment for PLA, however, for composite samples, increased heat treatment led to a small reduction in average tensile strength. Although there was no discernable trend for change of fracture toughness with increased crystallinity for PLA, it decreased for composite materials. It appears that the increased crystallinity present in the composite in combination with increased stress concentration due to the presence of fibres is reducing composite toughness as well as leading to premature failure in tensile tests due to PLA brittleness explaining lower strengths for composites. DMTA suggests that increase in crystallinity contributes to thermal stability of the composite.

year: 2010

title: Evaluation of Rongo Atea: Alcohol and Other Drug Treatment Centre for Adolescents

authors: Paki, Helen Mary

subjects: Alcohol

abstract: Abstract Rongo Ātea is a residential abstinence-based Kaupapa Māori alcohol and other drug programme accommodating youth between the ages of 13 and 17. This evaluation investigates the role that staff play at Rongo Ātea along with a number of other factors including the physical environment; stages of change; programme implementation and aftercare. As a Kaupapa Māori programme, the role of how culture and identity can influence positive change is also explored along with the development of a youth-focused approach. I utilised a three phase framework borrowed from the work of Mason Durie (2008) to organise themes. These three phases, which Durie (2008) based on marae encounters, include Whakapiri (Engagement); Whakamarama (Enlightenment); and Whakamana (Empowerment) as they aptly reflect a three phase intervention approach: detoxification and early programme engagement; learning and development through ongoing programme commitment; and post treatment outcomes and aftercare. The data collection phase of this evaluation took place in 2006 and was initiated by the manager of Rongo Ātea who requested an evaluation to identify programme strengths and limitations from the perspectives of staff and students, and to make recommendations to Rongo Ātea that would assist with further programme developments. I utilised a collaborative and participatory approach (Bishop, 1996; Patton, 1990). Kaupapa Māori research principles were reflected in the use of ‘kanohi kitea’— face to face contact (Smith, 1999). With appropriate training and management support, staff could have a greater influence on programme outcomes. Evaluation findings suggest that drug and alcohol intervention and treatment for young people in New Zealand is significantly under-resourced, particularly in the areas of detoxification and aftercare. To be effective, residential treatment programmes should consist of a three stage programme covering detoxification; treatment; and aftercare incorporating an integrated approach. A greater emphasis on working with whānau alongside the young person is recommended.

text: Evaluation of Rongo Atea: Alcohol and Other Drug Treatment Centre for Adolescents Abstract Rongo Ātea is a residential abstinence-based Kaupapa Māori alcohol and other drug programme accommodating youth between the ages of 13 and 17. This evaluation investigates the role that staff play at Rongo Ātea along with a number of other factors including the physical environment; stages of change; programme implementation and aftercare. As a Kaupapa Māori programme, the role of how culture and identity can influence positive change is also explored along with the development of a youth-focused approach. I utilised a three phase framework borrowed from the work of Mason Durie (2008) to organise themes. These three phases, which Durie (2008) based on marae encounters, include Whakapiri (Engagement); Whakamarama (Enlightenment); and Whakamana (Empowerment) as they aptly reflect a three phase intervention approach: detoxification and early programme engagement; learning and development through ongoing programme commitment; and post treatment outcomes and aftercare. The data collection phase of this evaluation took place in 2006 and was initiated by the manager of Rongo Ātea who requested an evaluation to identify programme strengths and limitations from the perspectives of staff and students, and to make recommendations to Rongo Ātea that would assist with further programme developments. I utilised a collaborative and participatory approach (Bishop, 1996; Patton, 1990). Kaupapa Māori research principles were reflected in the use of ‘kanohi kitea’— face to face contact (Smith, 1999). With appropriate training and management support, staff could have a greater influence on programme outcomes. Evaluation findings suggest that drug and alcohol intervention and treatment for young people in New Zealand is significantly under-resourced, particularly in the areas of detoxification and aftercare. To be effective, residential treatment programmes should consist of a three stage programme covering detoxification; treatment; and aftercare incorporating an integrated approach. A greater emphasis on working with whānau alongside the young person is recommended.

year: 2010