Submarine mass-wasting deposits as an indicator of the onset of foreland thrust loading—Late Permian Bowen Basin, Queensland, Australia

In the eastern part of the Permo-Triassic Bowen Basin of Queensland, Australia, a transition from passive, thermal subsidence to flexural (foreland basin) subsidence is recorded within the Upper Permian stratigraphy. Two coarse-grained intervals containing deposits of mass-wasting processes occur within an otherwise siltstone-dominated succession over 1500 m thick (the Moah Creek Beds and equivalents). These intervals can be traced over at least 350 km north–south, along the structural eastern margin of the basin. The lower of the coarse-grained intervals is spectacularly exposed in the banks of the Fitzroy River, west of Rockhampton. Here, interbedded sandstones and siltstones of marine shelf origin are abruptly truncated by a mudrock succession containing evidence of slumping and contemporaneous magmatic activity. This unit passes up-section into packages of mass-flow conglomerates and diamictites, interpreted to have formed on an unstable submarine slope. The character of the mass-flow deposits, their stratigraphic position and lateral extent are interpreted in terms of destabilization of a sloping marine surface by pulsed, subsurface thrust propagation.     

Cyclic sedimentation in the Permian coal measures of New South Wales

Statistical analysis of borehole sections through the Illawarra and Newcastle Coal Measures of the Sydney Basin shows that cyclic sedimentation is present. The composite sequence for the Southern Coalfield (Illawarra Coal Measures) is (in ascending order): sandstone—sandstone/siltstone alternations—shale—coal, whereas that for the Newcastle Coalfield is: shale—sandstone/siltstone alternations—sandstone, often conglomeratic, or conglomerate—sandstone/siltstone alternations—shale —coal.

The environment of deposition is discussed. It is suggested that in the Southern Coalfield cyclicity is due to sedimentational processes inherent in the deltaic and alluvial conditions envisaged during Permian times. Periodic influxes of glacial meltwaters, although not essential, are not ruled out.

In the Newcastle Coalfield, however, the composite sequence does not match easily the ideal cycles expected in deltaic and/or alluvial regimes. Contemporary volcanism and tectonism complicated matters and lack of sedimentological details makes it impossible at present to give preference to any one mechanism of cycle formation.     

Structure and tectonic history of the Brisbane metamorphics in the Brisbane area

The Palaeozoic basement rocks of the Brisbane area have undergone three major deformations and a minor kinking episode. The central zone of Bunya Phyllite is dominated by a second‐generation transposition layering whereas the flanking Neranleigh‐Fernvale Beds are dominated by first‐generation transposition structures.

The major structure previously described in the area, the Indooroopilly Anticline, is an apparent antiform formed in part by the intersection of dominant first‐ and second‐generation structures and in part by a major third‐generation flxeure. The complete geometry of the first‐generation layering across the structure is suggested using vergence relationships but the stratigraphic relations and the structure of the stratigraphic boundaries are virtually impossible to deduce. Two possibilities are suggested and a major conclusion is that the Bunya Phyllite may be merely a unit within the Neranleigh‐Fernvale Beds.

The first‐generation deformation is a regional event whose effects can be traced north for some 500 km whereas the second‐ and third‐generation structures are more restricted. There is evidence to suggest that all three generations may be related to the same tectonic event, possibly Carboniferous in age.     

Dispersive Liquid–Liquid Microextraction for Preconcentration and Determination of Nickel in Water

A method for the determination of nickel in water was developed. The procedure involves preconcentration of nickel by using dispersive liquid–liquid microextraction. The Ni(II) ions were extracted in chloroform in the form of complex with the reagent 2‐(2′‐benzothiazolylazo)‐p‐cresol. Ethanol was used as the disperser solvent. After injection of the extracting mixture in a solution of nickel, a cloudy mixture was observed. A quick centrifugation induces phase separation and thus the settling of rich phase. The nickel content in the rich phase is measured by flame atomic absorption spectrometry. Under optimal conditions, the limit of detection and quantification obtained were 1.4 and 4.7 µg L^?1, respectively. Some parameters used to characterize preconcentration systems, such as enrichment factor and consumption index were calculated and resulted in 29 and 0.34 mL, respectively. After optimization of variables and determination of analytical characteristics, the method was used for the analysis of certified reference materials (BCR‐713: wastewater, effluent and BCR‐414: plankton) and real water samples.     

A late Pleistocene record of aeolian sedimentation in Blanche Cave, Naracoorte, South Australia

We provide geochemical analyses and grain size data for a clearly layered, 80 cm thick sedimentary deposit close to a roof collapse in Blanche Cave near Naracoorte in SE South Australia. This deposit contains aeolian material deposited between 40 ka and 14 ka cal BP and which yields airborne sediments spanning the Last Glacial Maximum, a period of time with little information for the Australian continent. The deposit also contains abundant vertebrate fossil material derived from owl pellets, accumulation and pitfall entrapment. Below the studied profile, large vertebrate remains are found but are not discussed here. No Holocene sedimentation occurred at the site examined in the cave, and the top of the sequence is capped with a layer that has been anthropologically disturbed and contains exotic Pinus pollen. Chronologies of the deposit were obtained using two dating techniques: single stage accelerator mass spectrometer (SSAMS) ¹⁴C analysis of 23 charcoal samples and optically stimulated luminescence (OSL) dating of quartz from 6 sediment samples. The ¹⁴C chronology is preferred to describe the history of the deposits since the OSL chronology, which consistently overestimates the associated radiocarbon dates, may be inaccurate due to complexities in calculating dose rates, and may in addition represent the timing of sediment deposition through the cave opening rather than sediment transport to the deposit site. Morphological analysis of single quartz grains and grain size analysis indicate different provenance that is confirmed through the geochemical analyses of bulk sediment. Major elements were measured by X-ray Fluorescence (XRF), trace and rare earth elements by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA ICP-MS), and Neodymium isotopic ratios were obtained using a Thermal Ionisation Mass Spectrometer (TIMS).Our results indicate that the aeolian material deposited in Blanche Cave over the 40–14 ka cal BP period originated from different sources across South Australia, although Nd isotopes clearly indicate a close association with sediments of the Kanmantoo Group outcropping along the eastern portion of the Mount Lofty Ranges and the Padthaway Ridge further south, both being located to the NW and NNW of the cave. During the latter part of Marine Isotope Stage 3, conditions were wetter and windblown sediment came from the coastal region just north and south of the Coorong Lagoon, with winds originating from the north-northwest. At that time, woody taxa appear to have vegetated the landscape. During the drier phases, especially the Last Glacial Maximum, sediment came from further inland, thus suggesting a different predominant wind direction, more from the northwest. The deglaciation saw material originating from a more northerly direction.     

T—lnP图的制作及一些稳定度指数不稳定能量的计算

本文对T－lnP图（即埃玛图）的制作及一些稳定度指数和不稳定能量的计算进行了较为详细的说明，并进行了实际验证，表明用计算机进行温度对数压力图的制作，不仅方便快捷准确，而且能避免人为的误差。     

Earthquake foci distribution in the Sunda Arc and the rotation of the backarc area

Earthquake foci suggest that the India plate has been underthrust in the Sunda Arc to depths increasing from little more than 200 km beneath central Sumatra to well over 600 km beneath the Java Sea. Geological differences between Sumatra and Java do not fully account for the anomaly. The explanation would appear to lie with an oblique India-Eurasia convergence caused by the rotation, relative to Eurasia, of the Sunda backarc area. Sinistral movements on several southeast-trending wrench faults in the region between Yunnan and Java appear to have been responsible. Backarc rotation also explains the pattern of Cenozoic volcanicity in Sumatra, and resolves controversy over the nature of the Andaman Basin, which may be interpreted as a rhombochasm forming behind a locally divergent plate margin.     

Is counselling a feminist practice?

Women’s efforts to influence policies have complex effects, which are often difficult to evaluate. This paper identifies four themes in feminist politics through which to analyse whether a particular intervention involving substantial numbers of women – that of counselling in the UK – can be understood as a feminist practice. These themes are concerned with gender equality, women’s autonomy, recognition of diversity among women and the deconstruction of gender norms. In its early post-war origins prior to the emergence of second wave feminism, and in the stories recounted by women practitioners at the turn of millennium, counselling emerges as contradictory and ambivalent in relation to these themes in feminist politics.