Three years on: Indigenous families and the welfare system, the Kuranda community case study

This discussion paper presents the results from the third and final year of the Kuranda community case study for the project on the delivery of appropriate welfare services and policies to Indigenous families. Core recommendations and conclusions from the project as a whole are also discussed. Three years of survey data now allow a comparison of sources of household income. Indigenous families and households in the community remain highly dependent on income support from welfare benefits and pensions, and from the CDEP scheme. The research also points to Abstudy payments as playing an important part in family domestic economies. One of the key issues highlighted for service delivery and policy consideration is the complexity of patterns of residential mobility of Indigenous adults and children in Kuranda. Taking into consideration all the people surveyed in 2000 and 2001, one out of every two persons had moved into or out of the house- hold sample. Over half of those people were children, or young adults aged 17-25 years. Importantly, the existence of a non-mobile core of household members-usually older people on secure pensions-is identified as a point of domestic stability for children and youth. Child-care is an extended family, rather than a household-centred activity, and the mobility of children and youth is an expression of extended family networks. The key role played by older women in the care of children is emphasised once again. The results raise several important issues for policy and service delivery. The fact that child-care is family-based rather than household-based needs to be recognised in the delivery of welfare services to children and in policy frameworks. Many children have multiple carers who are in need of financial support for the period in which they are responsible for a child. There needs to be flexibility in the service arrangements so that the relevant family payments are going to the person actually caring for a child. The three survey waves have identified an important characteristic of young adults: there appears to be no transition for this group from school into mainstream local employment. The main transition is, in fact, into early dependence on welfare or CDEP payments. If inter-generational welfare dependence is to be short-circuited, there needs to be immediate targeted policy and program support for this age group, preferably before they enter the welfare system. It is proposed that a Youth Work Preparation and Employment Program be piloted, focusing on young CDEP participants and school leavers. The program would be delivered by local CDEP organisations with the objective of creating a detour around early dependence on welfare and CDEP incomes, by mentoring the transition of young adults into local work experience and main-stream employment

Mineralogy and Phase Chemistry of Mount St. Helens Tephra Sets W and Y as Keys to Their Identification

Voluminous and widespread tephras were produced frequently during the last 36,000 yr of volcanic activity at Mount St. Helens. Numerous tephra sets have been defined by D. R. Mullineaux, J. H. Hyde, and M. Rubin (1975, U.S. Geological Survey Journal of Research, 3, 329–335) on the basis of field relations, Fe-Mg phenocryst assemblage, and 14C chronology and are valuable marker beds for regional stratigraphic studies. In this study modal abundances and mineral compositions were determined (via petrographic and electron microprobe techniques) for numerous samples of individual layers within tephra sets W and Y to evaluate the degree of compositional variability within and between tephra layers and criteria by which to distinguish among Mount St. Helens and other Pacific Northwest tephras. Although individual layers within a set (e.g., We, Wn) cannot be distinguished from each other on the basis of mineralogic characteristics examined, mineral compositions allow distinction among layers W and Y and other Pacific Northwest tephras (e.g., Mazama, Glacier Peak). Fe-Ti oxide compositions and T-ƒO2 estimates derived using coexisting magnetite-ilmenite are especially useful due to the compositional homogeneity of these minerals both within and between samples of a given unit over a wide geographic area. The silicates show more compositional variability than the oxides, but SiO2/Al2O3 contents in hornblende and Fe/Mg ratios in hypersthene aid in distinguishing among Pacific Northwest tephras

Chromian Spinel–Olivine Phase Chemistry and the Origin of Primitive Basalts of the Southern Washington Cascades

Geochemically diverse basalts occur in an ~160-km-wide transect that stretches across the Quaternary southern Washington Cascades (SWC) volcanic arc. Two fundamental groups of SWC basalts can be identified on the basis of major and trace element chemistry. On primitive mantle-normalized “spidergrams”, Group I lavas resemble within-plate basalts, whereas Group II lavas exhibit chemical characteristics (e.g., Nb, Ta, and Ti depletions) typical of subduction-related magmas. The primitive nature of many SWC basalts is indicated by their high MgO (\u3e6.5 wt.%, up to 9.5 wt.%), Ni (\u3e85 ppm) and Cr (\u3e180 ppm) contents. Electron microprobe analyses of olivine–spinel pairs in a diverse suite of SWC basalts are used to further evaluate the primitive nature of these magmas. Some of the observed variations in olivine–spinel compositions can be attributed to oxidation, fractionation, mixing, and/or pressure variations during magma evolution. To minimize these effects, we focus on olivine-hosted spinels in samples for which olivine-host rock equilibrium can be demonstrated. Spinels in such rocks have Fe2O33+/(Fe3++Cr+Al)2+)\u3e44] and low Cr# [=100 Cr/(Cr+Al) 45) for Group II lavas; (3) spinel Mg# ranges from 45 to 71, and overlaps for Groups I and II. However, each group defines distinct trends on Mg# vs. Cr# and other variation diagrams, with Group II having more refractory characteristics. This observation is consistent with higher whole-rock Mg# and Fo contents of olivines for Group II lavas, and suggests that sources for those magmas are more refractory (i.e., more melt-depleted) than sources for Group I lavas. The “within-plate”-like chemistry of Group I lavas precludes significant slab-derived contributions and is consistent with their derivation by decompression melting of little modified and relatively fertile mantle wedge material upwelling beneath the arc. The fluid-mobile element-enriched nature of Group II lavas is consistent with melting of a mantle source(s) that has been modified by slab-derived fluids. However, the standard “flux melting” process invoked to explain formation of many arc magmas is problematic for the Cascades because (a) high temperatures inferred for the Cascadia subduction zone imply that the slab may be extensively dehydrated, in which case the inventory of volatiles and fluid-mobile elements is likely to be strongly depleted; and (b) Group I lavas occur at the volcanic front and appear to originate at depths proximal to the subducting slab. These geochemical and geometric constraints seem inconsistent with formation of Group II magmas by flux melting of the mantle wedge as commonly proposed for arcs. An alternative source for Group II lavas is chemically refractory lithospheric mantle that was previously metasomatized by earlier (40 Ma to present) Cascadia subduction and associated magmatism. Reheating and melting of such fluid-enriched domains could result from influx of hot decompression melts (Group I magmas). In either case, chemical and mineralogical evidence implicates two (or more) distinct processes of melt production and at least two distinct types of mantle source

Petrogenesis of Mount St. Helens Dacitic Magmas

The most frequent and voluminous eruptive products at Mount St. Helens are dacitic in composition, although a wide variety of magma types (basalt to rhyodacite) is represented. To address the petrogenesis of the dacites, we present major and trace element analyses of samples of pumice clasts and dome or flow lavas erupted during the past ∼40,000 years. The dacites have similar (in some cases even lower) contents of many incompatible elements (e.g., Zr, Hf, REE, U, Be, Ta, Nb) compared with those in associated basalts and andesites, whereas Ba, Rb, K, Cs, and Sr are relatively enriched. The unusual depleted nature of the dacites and generally low bulk distribution coefficients (estimated from glass/whole‐rock pairs) for numerous trace elements preclude an origin of these magmas principally by crystal fractionation of associated mafic magmas. A more plausible model for their origin involves melting of metabasaltic crustal rocks that have been enriched in Ba, Rb, Cs, and Sr by either intercalation of sediments with depleted basalt or selective metasomatic enrichment of the source region. Melting at crustal levels presumably is related to intrusion of mantle‐derived basaltic magmas. Compositional diversity among the erupted dacites can be attributed to spatial or temporal heterogeneity of the magma sources or, in some specific cases, to such processes as crystal fractionation, assimilation, and magma mixing

The Effects of Temperature and ƒ\u3csub\u3eO\u3csub\u3e2\u3c/sub\u3e\u3c/sub\u3e on the Al-in-Hornblende Barometer

The Al-in-homblende barometer potentially offers a basis for estimating crystallization pressure for granitic batholiths. However, owing to the simplicity of its formulation, misuse of the barometer can occur. Many granitic intrusions are emplaced at conditions inconsistent with those of the existing experimental calibrations, including fO2 \u3c NNO and/or variable to high temperature. The barometer is sensitive to variations in both fO2 and temperature: low fO2 can cause calculated pressures to be high by a factor of two or more, and the effect of temperature is up to 2 kbar per 100 °C, depending on total Al abundance. Batholiths emplaced at elevated temperature and portions of plutons that crystallized below H2O saturation yield artificially high pressures relative to near-solidus experiments conducted at H2O saturation. Al-in-homblende pressures within the tonalitic Mount Stuart batholith of Washington, for example, define a 1–4 kbar domal structure that is exaggerated by emplacement crystallization temperatures that range from 620 to 760 °C. Pressure correlates with temperature (r2 = 0.86), indicating that temperature-sensitive edenite exchange has greatly influenced observed pressure variations. Data for other plutons also exhibit a marked positive correlation between temperature and hornblende pressure. If corrections are not made for temperature, such large apparent pressure variations can lead to overly high estimates of pluton thickness and tilt in addition to invalid tectonic interpretations. Using experimental data at ~675 °C (Schmidt, 1992) and at ~760 °C (Johnson and Rutherford, 1989), a revised expression for the barometer incorporating the effect of temperature is P (±0.6 kbar) = 4.76Al − 3.01 − {[T(°C) − 675]/85} × {0.530Al + 0.005294[T (°C) − 675]}. For a pluton emplaced at 100 °C above wet-solidus temperatures, this reformulation of the barometer lowers derived pressures by 1.3 to \u3e2 kbar at typical crustal pressures. For the Mount Stuart batholith, consideration of temperature yields revised pressures that are in agreement with pressures obtained from wall rocks and eliminates much of the apparent domal structure. Low-/fO2 granites have amphibole Fe/(Fe + Mg) ratios that exceed the typical 0.40−0.65 range used in most experimental and empirical calibrations. Examples from anorogenic granitic batholiths of mid-Proterozoic age yield pressures that are too high by a factor of two to three in comparison with pressures obtained from adjacent metamorphic assemblages. Hornblende in these granites not only has high Fe/(Fe + Mg) but also low ratios of Fe3+ to Fe2+. The anomalously high Al in Fe-rich, Fe3+-poor hornblende is inferred to be the result of increased [6]Al occupancy of the M2 site not buffered by the Mg and Fe3+ abundances typical of amphiboles in calc-alkaline and other high-fO2 plutonic rocks

The Origin of Mount St. Helens Andesites

Mount St. Helens volcano has intermittently produced mainly dacitic products but occasionally erupted a more diverse suite of lavas including basalts and andesites. Petrogenetic relations between these magmas provide insight into the dynamics of the subjacent magma system. Mineralogical and geochemical features of representative lavas erupted during the past 2200 years can distinguish three basaltic and three andesitic variants. The mafic lavas include: (a) transitional, olivine + plagioclase basalts with low K2O and incompatible trace-element abundances: (b) calc-alkaline, olivine + plagioclase ± clinopyroxene basalts enriched in K 2O, TiO2, and incompatible trace elements: and (c) calc-alkaline, olivine + plagioclase basaltic andesites with incompatible trace-element contents transitional between the two basalt types. Intermediate lavas include (a) tholeiitic, two-pyroxene andesites, (b) calc-alkaline, plagioclase + two-pyroxenes ± olivine ± amphibole mafic andesites (56-59% wt.% SiO2), and (c) calc-alkaline, plagioclase + two-pyroxenes + amphibole high-silica andesites (61-62 wt.% SiO2). Eruption of these magmatic variants within the same eruptive phase implies the existence of different petrogenetic lineages, and that the plumbing system is sufficiently complex to simultaneously isolate and preserve numerous magma batches. It is unlikely that any of the andesites (or dacites) are derived by fractional crystallization of the recognized basaltic variants. Formation of the andesites simply by contamination (or assimilation-fractional crystallization) of basaltic magma is also improbable. More plausibly, the andesites represent mixing between basaltic and dacitic end-member magmas, each of which may be somewhat heterogeneous or vary in composition with time. In this model, efficient mixing must occur in some parts of the magma plumbing system, while some conduits or storage reservoirs must be effectively isolated

Indigenous welfare policy: lessons from a community survey

Although Indigenous Australians only represent two per cent of the Australian population, they have a high profile in the community as the original inhabitants of the continent and because of the problems associated with their poverty, dispossession and welfare dependence. In this article we present a summary of research findings from a three-year study conducted among Indigenous people living in and around the town of Kuranda in Northern Queensland — about half an hour’s drive inland from Cairns

The development of a measure of social care outcome for older people. Funded/commissioned by: Department of Health

An essential element of identifying Best Value and monitoring cost-effective care is to be able to identify the outcomes of care. In the field of health services, use of utility-based health related quality of life measures has become widespread, indeed even required. If, in the new era of partnerships, social care outcomes are to be valued and included we need to develop measures that reflect utility or welfare gain from social care interventions. This paper reports on a study, commissioned as part of the Department of Health’s Outcomes of Social Care for Adults Initiative, that developed an instrument and associated utility indexes that provide a tool for evaluating social care interventions in both a research and service setting. Discrete choice conjoint analysis used to derive utility weights provided us with new insights into the relative importance of the core domains of social care to older people. Whilst discrete choice conjoint analysis is being increasingly used in health economics, this is the first study that has attempted to use it to derive a measure of outcome

Petrogenesis of Mid-Proterozoic Granitic Magmas: Examples from Central and West Texas

Circa 1.1 Ga granitic magmatism in Texas was manifested as two compositional groups: (1) the 1.12 Ga Red Bluff granitic suite in west Texas; and (2) 1.12-1.07 Ga granites of the Llano uplift of central Texas. Both suites share some characteristics typical of \u27anorogenic\u27 granites (e.g. potassium- and iron-rich bulk compositions, Fe-rich hydrous silicates, emplacement conditions involving low oxygen fugacities and water contents) and exhibit similar isotopic characteristics. However, rock associations, mineral chemistries, and trace element compositions of the two suites are distinct and no single petrogenetic model for the two suites is possible. The Red Bluff granitic suite includes cogenetic syenites, quartz syenites and granites; transitional ferrobasaltic dikes are also present. In contrast, syenitic and mafic rocks are not associated with the Llano granites. The Llano granites contain biotite and calcic amphibole with lower Fe/(Fe+Mg) ratios compared to those occurring in the Red Bluff rocks. Alkali amphiboles (e.g. arfvedsonite) occur in the Red Bluff granites but not in the Llano granites. The Red Bluff granitoids are characterized by high FeOT/MgO ratios, high (Na2O+K2O), high concentrations of HFSE and rare earth elements (REE), and other features typical of A-type, \u27within-plate\u27 granites [e.g. the Pikes Peak batholith (PPB)]. The Llano granites are geochemically distinct with generally higher P2O5 and Sr, lower Na2O, FeOT/MgO, Zr, Y and REE, and much lower Ta and Nb. Nd isotopic data overlap between the two granite suites and have \u27juvenile\u27 signatures. However, trace element data suggest different petrogeneses for the two suites. The Red Bluff suite is interpreted as having a direct derivation from mantle sources via extended fractional crystallization of basaltic parental magmas, with minor crustal assimilation. The Llano granites appear to represent anatectic melts derived from slightly older, juvenile crustal sources; some melts underwent fractional crystallization controlled by feldspar and accessory minerals. The petrology and geochemistry of ~1.1 Ga granites in Texas indicate that they should not be considered as part of a single \u27anorogenic\u27 magmatic event. The Red Bluff granitic suite was emplaced into a shelf sequence, north of the Grenville Front, within a broad zone characterized by mild extension. In contrast, Llano granites are late-stage intrusions emplaced into multiply deformed and metamorphosed crust, south of the Grenville Front, during or after waning stages of Grenville orogenesis