title: Provenance history of a Late Triassic-Jurassic Gondwana margin forearc basin, Murihiku Terrane, North Island, New Zealand: petrographic and geochemical constraints

authors: Briggs, Roger M.

subjects: Murihiku Terrane

abstract: The Murihiku Terrane in the North Island was a forearc basin adjacent to a volcanic arc along the eastern margin of Gondwana during the Mesozoic. The rocks that infill the basin are mainly volcaniclastic sandstones and mudstones, often turbiditic, with sparse shellbeds, rhyolitic tuffs, carbonaceous sandstones, plant beds, concretionary horizons, and rare thick granitoid-rich conglomerates. Petrographic studies of the rock fragments in the sandstones show that andesites are the dominant lithic type, but there is a wide range of other lithologies, including dacites, rhyolites, ignimbrites, granitoids, quartzofeldspathic mica schists, rare amphibolites, and reworked mudstones and sandstones. The sandstones are texturally and mineralogically immature and suggest deposition relatively close to a source of high relief, undergoing physical rather than chemical weathering in cool- to cold-temperate conditions. Geochemical analyses of 67 whole-rock volcaniclastic sandstones and siltstones indicate that they were derived from an active and dissected volcanic arc in a convergent margin setting built upon relatively thin continental crust. Modal petrographic data and whole-rock geochemistry both confirm that there were systematic variations with time in the composition of clastic material being supplied to the basin. From the Late Triassic to Middle Jurassic, there was a decrease in silicic volcanic material, plutonics, and metamorphics, and an increase in the supply of andesitic detritus. This was followed in the Late Jurassic by a broader range of volcanic detritus, varying from basaltic andesite to rhyolite, which may have been caused by progressive extension of the volcanic arc and thinning of the crust, a precursor to the breakup of Gondwana in the Early-Middle Cretaceous. Comparison with the Southland segment of the Murihiku Terrane in the South Island suggests that there were significant along-arc source variations, with relatively less silicic but greater andesitic and continental crust contributions in the North Island than in Southland. This may be analogous to the modern Taupo-Kermadec arc where there is a south-north along-arc transition from a continental to an oceanic arc.

text: Provenance history of a Late Triassic-Jurassic Gondwana margin forearc basin, Murihiku Terrane, North Island, New Zealand: petrographic and geochemical constraints The Murihiku Terrane in the North Island was a forearc basin adjacent to a volcanic arc along the eastern margin of Gondwana during the Mesozoic. The rocks that infill the basin are mainly volcaniclastic sandstones and mudstones, often turbiditic, with sparse shellbeds, rhyolitic tuffs, carbonaceous sandstones, plant beds, concretionary horizons, and rare thick granitoid-rich conglomerates. Petrographic studies of the rock fragments in the sandstones show that andesites are the dominant lithic type, but there is a wide range of other lithologies, including dacites, rhyolites, ignimbrites, granitoids, quartzofeldspathic mica schists, rare amphibolites, and reworked mudstones and sandstones. The sandstones are texturally and mineralogically immature and suggest deposition relatively close to a source of high relief, undergoing physical rather than chemical weathering in cool- to cold-temperate conditions. Geochemical analyses of 67 whole-rock volcaniclastic sandstones and siltstones indicate that they were derived from an active and dissected volcanic arc in a convergent margin setting built upon relatively thin continental crust. Modal petrographic data and whole-rock geochemistry both confirm that there were systematic variations with time in the composition of clastic material being supplied to the basin. From the Late Triassic to Middle Jurassic, there was a decrease in silicic volcanic material, plutonics, and metamorphics, and an increase in the supply of andesitic detritus. This was followed in the Late Jurassic by a broader range of volcanic detritus, varying from basaltic andesite to rhyolite, which may have been caused by progressive extension of the volcanic arc and thinning of the crust, a precursor to the breakup of Gondwana in the Early-Middle Cretaceous. Comparison with the Southland segment of the Murihiku Terrane in the South Island suggests that there were significant along-arc source variations, with relatively less silicic but greater andesitic and continental crust contributions in the North Island than in Southland. This may be analogous to the modern Taupo-Kermadec arc where there is a south-north along-arc transition from a continental to an oceanic arc.

year: 2004-12-01

title: Informing supervision practice through research: A narrative inquiry

authors: Crocket, Kathie

subjects: narrative

abstract: Intention: This study focused on questions of whether and how clients benefit from supervision. As practitioner research, the study was intended to shape the researchers' own supervision practice. Method: The qualitative approach was based on interviews with a small number of experienced practitioners about their supervision experiences. The findings are presented in the form of reflexive stories, told by each researcher. Findings: In these stories the researchers tell how engagement with experienced practitioners' accounts of their past supervision shaped the hopes and intentions the researchers hold for their future supervision. Implications for practice: The stories suggest there are therapeutic benefits in an ethic of transparency that provides for practices that overtly carry stories in both directions between counselling and supervision.

text: Informing supervision practice through research: A narrative inquiry Intention: This study focused on questions of whether and how clients benefit from supervision. As practitioner research, the study was intended to shape the researchers' own supervision practice. Method: The qualitative approach was based on interviews with a small number of experienced practitioners about their supervision experiences. The findings are presented in the form of reflexive stories, told by each researcher. Findings: In these stories the researchers tell how engagement with experienced practitioners' accounts of their past supervision shaped the hopes and intentions the researchers hold for their future supervision. Implications for practice: The stories suggest there are therapeutic benefits in an ethic of transparency that provides for practices that overtly carry stories in both directions between counselling and supervision.

year: 2009

title: A Journey Beyond the Bars: Participants' Experiences of Psychological Treatment in a Prison Setting

authors: Terrill, Damian James

subjects: Prison

abstract: This study explored the experiences of high-risk male offenders at varying stages of a prison-based residential rehabilitation programme. Information was elicited by means of 1:1 semi-structured interviews with three adult offenders: one programme completer, one approaching completion and one non-completer. The opinions of three members of unit staff (two programme facilitators and one custodial officer) were also included. Having identified a lack of process-focused qualitative research in the criminological literature, this thesis has attempted to provide an insight into the lived experiences of offenders undergoing a residential rehabilitative intervention. The results are presented through a combined postmodernist, social constructionist discourse. They identify a series of coherent themes which emphasise the importance of numerous contextual, linguistic and communicative variables in dictating the participants’ self-perspectives and engagement with treatment. I will examine in particular, the role of motivation, the importance of the therapeutic bond established between participants and therapists, the relevance of the therapeutic environment, and the impact of both bi-cultural therapy and notions of individual stigmatisation. The overall findings are related to the broader penological literature in order to inspire further experiential analyses of offenders undergoing treatment, and to offer points for consideration in the application of prison-based rehabilitative interventions.

text: A Journey Beyond the Bars: Participants' Experiences of Psychological Treatment in a Prison Setting This study explored the experiences of high-risk male offenders at varying stages of a prison-based residential rehabilitation programme. Information was elicited by means of 1:1 semi-structured interviews with three adult offenders: one programme completer, one approaching completion and one non-completer. The opinions of three members of unit staff (two programme facilitators and one custodial officer) were also included. Having identified a lack of process-focused qualitative research in the criminological literature, this thesis has attempted to provide an insight into the lived experiences of offenders undergoing a residential rehabilitative intervention. The results are presented through a combined postmodernist, social constructionist discourse. They identify a series of coherent themes which emphasise the importance of numerous contextual, linguistic and communicative variables in dictating the participants’ self-perspectives and engagement with treatment. I will examine in particular, the role of motivation, the importance of the therapeutic bond established between participants and therapists, the relevance of the therapeutic environment, and the impact of both bi-cultural therapy and notions of individual stigmatisation. The overall findings are related to the broader penological literature in order to inspire further experiential analyses of offenders undergoing treatment, and to offer points for consideration in the application of prison-based rehabilitative interventions.

year: 2010