13 resultados para basin of attraction

em Deakin Research Online - Australia


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The Late Permian Shaiwa Group of the Ziyun area of Guizhou, South China is a deep-water facies succession characterized by deep-water assemblages of pelagic radiolarians, foraminifers, bivalves, ammonoids and brachiopods. Here we report 20 brachiopod species in 18 genera from the uppermost Shaiwa Group. This brachiopod fauna is latest Changhsingian in age and dominated by productides. The palaeoecologic and taphonomic analysis reveals that the brachiopod fauna is preserved in situ. The attachment modes and substratum preference demonstrate that the Shaiwa brachiopod fauna comprises admixed elements of deep-water and shallow-water assemblages. The presence of the shallow-water brachiopods in the Shaiwa faunas indicates the involuntary settlement of shallow-water brachiopods. The stressed ecologic pressure, triggered by warming surface waters, restricted ecospace and short food sources, may have forced some shallow-water elements to move to hospitable deep-water settings and others to modify their habiting behaviours and exploit new ecospace in deep-water environments. We infer that the end-Permian global warming and subsequent transgression event may have accounted for the stressed environmental pressure in the shallow-water communities prior to the end-Permian mass extinction.

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The Anzali Ramsar Convention wetland is located in an ecologically and economically important region in Iran. The wetland is largely surrounded by agriculture, natural forests and rangelands (approximately 36% and 63%, respectively). Urban areas consist of less than 1% of the total area. Urban land use produces the highest rates of nutrient transfer into the lake as TN, TP and BOD5 equal to 24, 2.4 and 79 Kg/ha/year, respectively, whilst, natural land use produces the lowest rate as 10, 1.3 and 27 kg/ha/year. These results will inform the future sustainable management of this important wetland in this ever increasingly water stressed region in Iran.

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Four new Early Carboniferous athyridid species in three genera, including one new genus, Bruntonathyris, are described from the Qaidam Basin, northwest China: Lamellosathyris qaidamensis, Bruntonathyris amunikeensis, Bruntonathyris? heijianshanensis, and Lochengia qinghaiensis. Based on the new material and also on published information, we also reviewed the taxonomic composition and the stratigraphic and paleogeographic distributions of the three genera. As a result, Lamellosathyris is considered to be indicative of late Famennian to Viséan age, originating in late Famennian in central North America and Armenia of Russia, respectively. Later, the genus appears to have two migratory directions: one branch rapidly dispersed over Mississippi Valley, Oklahoma, Texas and New Mexico of central North America in Tournaisian; alternatively, another branch from Armenia migrated westerly to Belgium, France, Spain, Britain, Ireland, via the Moscow Basin and Ural seaway, eastward to the Tienshan Mountains and Qaidam Basin of northwest China during the Tournaisian to Viséan, and easterly along the southern shelves of the Paleo-Tethys to Iran and western Yunnan of southwestern China in Tournaisian. Both Bruntonathyris and Lochengia are restrictedly Tournaisian to Viséan in age, and probably originated in the Qaidam Basin. Later, Bruntonathyris migrated easterly to South China and Japan, and westerly to Urals, Moscow Basin, Donetsk Basin and Britain; Lochengia migrated easterly to South China and westerly to the Urals seaway and the adjoined Russian Platform (i.e., both the Moscow and Donetsk Basins).

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Sydney Basin is located in the eastern part of Australia, Lachlan Fold Belt, and between the New England Fold Belt. From the Sydney basin at the end of the Late Carboniferous to Middle Triassic experienced back-arc spreading to the foreland basin at different stages: back-arc spreading stage (Carboniferous ), A passive thermal subsidence stage (early in the Permian Berry) and load deflection extruding stage (in Broughton Permian - Triassic). This time at the Sydney basin on the eastern side of the New England Fold Belt for the island Background of the arc. As a result, back-arc in the Permian Basin of the South Sydney basin by the back-arc spreading the eastern side of the arc and trench subduction before the impact of strong seismic activity, the development of a series of earthquake-related seismites to form various types and Seismic activity related to the deformation of soft sediment structure. Permian Basin, South Sydney's soft sediment deformation including cracks in shock-fold, liquefied vein, volcanic sand, load structure, flame Construction, pillow-like structure, spherical structure, pillow Layer structure slump, and so breccia. To which the cracks in shock-fold fibrillation is a direct result of earthquake faults and folds; pillow is a layer of sand caused by the earthquake fibrillation dehydration, the formation of the sinking; liquefied vein, Volcanic sand for the liquefaction of sand penetration of the formation of earthquake fissures formed; load structure, flame Construction, pillow-like structure, spherical structure is affected by the earthquake fibrillation in the sand, mudstone interface because of the sinking sand, mud layer formed through ; Slump structures and breccia of the earthquake was caused by the gravitational collapse or the formation of the debris flow. Fissures, earthquake-fold, liquefied vein, volcanic sand, load structure, flame Construction, pillow-like structure, spherical structure, pillow-like layer Equivalent to the original earthquake rocks the plot, and the slump structures and breccia of the plot belong to different earthquake rocks.

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Isogramma manchoukuoensis from the Upper Carboniferous of northeast China is redefined based on re-examination of the type specimens. Isogramma specimens from the Middle Permian of northeastern Japan are reassigned to I. aff. paotechowensis. A new family, Schizopleuroniidae, is proposed to include Schizopleuronia, but excludes Megapleuronia, which belongs to the Megapleuroniidae Liao, 1983. The family Isogrammidae is considered to be a transitional group in the eichwaldid-isogrammid-schizopleuronid evolutionary lineage within the Dictyonellida. A review of the global distribution of Isogramma species reveals that the genus has a total of 56 species ranging from the Mississippian (Early Carboniferous) to the Lopingian (Late Permian). Isogramma diversified rapidly after its origination in the middle Viséan and its species diversity remained high throughout the Mississippian. The genus possibly suffered a severe mid-Carboniferous boundary mass extinction, with no Early Carboniferous species surviving this event. Bashkirian Isogramma species show low diversity, followed by a global recovery in the Moscovian. During the latest Carboniferous Isogramma became highly diversified again. At the Carboniferous–Permian (C/P) transition Isogramma underwent another dramatic diversity drop, followed by several stepwise declines in diversity during the Early–Middle Permian. The Wuchiapingian I. sinosa is the last Isogramma species.

Ukraine was the possible centre of origin for Isogramma. From Ukraine Isogramma spread over the Moscow Basin of Russia, Central Europe (Germany, Austria), South Europe (Spain) and West Europe (England, Ireland and Scotland), and migrated to the North American midcontinent and South China during the late Viséan (Early Carboniferous). In Europe, Isogramma migrated to Spain and eastern Europe (Serbia) in the Moscovian, from there it then dispersed into Central Asia (Uzbekistan and Kazakhstan) in the Kasimovian-Gzhelian. In the Palaeo-Tethys Isogramma migrated from South China to northeast and northwest China in the Moscovian, spread over the North China Block during the C/P transition, moved to Russian Siberia, Japan and the Qiangtang terrane of the Palaeo-Tethys during the Early–Late Permian. In North America Isogramma spread over the midcontinent during the Late Carboniferous and Early–Middle Permian and migrated to South America (Bolivia) in latest Carboniferous. Biogeographically, Isogramma was confined principally to the palaeo-tropical and warm to temperate zones throughout the Late Palaeozoic, with the possible exception of the Artinskian, as a questionable species of the genus also occurs in the Transbaikal region of southeast Russia.

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Six Early Carboniferous brachiopod species in four genera of the Superfamily Spiriferoidea are described from the Qaidam Basin, northwestern China, including a new genus, Qaidamospirifer, and two new species: Grandispirifer qaidamensis and Qaidamospirifer elongatus. Additionally, a new genus, Triangulospirifer, is also proposed to replace Triangularia (Poletaev, 2001) that was preoccupied by a Devonian molluscan genus.

On the basis of the new material as well as published information, we have reviewed the taxonomic composition and the stratigraphic and palaeobiogeographic distributions of the three previously established genera from the viewpoint of palaeobiogeography. The study reveals that Grandispirifer has a relatively long stratigraphic range from the late Tournaisian to Serpukhovian. During this interval, the genus attained a wide geographical distribution, reaching Northwest China, western Yunnan of West China, Japan, as well as Iran and North Africa. Angiospirifer first occurred in western Europe in the Viséan, and later migrated to North Africa during the late Viséan. In the Serpukhovian, it migrated eastward, reaching the Donets Basin of Ukraine and the Qaidam Basin in Northwest China. Anthracothyrina evolved from Brachythyrina in North Africa in late Viséan, then dispersed north-westward to western and eastern Europe and, further eastward to the Qaidam Basin during the Serpukhovian.

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A unique marine Permian-Triassic boundary section containing rich oil source rocks has been continuously cored in a petroleum borehole from the Perth Basin of Western Australia. Such sequences, which provide a biostratigraphic and environmental record at the time of the largest extinction event of the past 500 million years, are globally rare, and this is the first to be documented in Australia. Throughout geological history there have been periods of global marine anoxia that commonly resulted in the widespread deposition of petroleum source rocks, most notably in the mid-Cretaceous and Late Jurassic. An apparent paradox is that, previously, source rocks have not been recognised in association with the Permian-Triassic boundary, despite widespread marine anoxia at this time. The Perth Basin source rocks contain abundant and unusual biomarkers, apparently related to the highly specialised and limited biota that flourished in the aftermath of the end-Permian extinction event. Local conditions may have favoured source-rock development, either due to higher productivity resulting from coastal upwelling or through enhanced preservation under strongly anoxic conditions.

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Two types of pyrite framboids (PF, probably sulphate-reducing bacteria) have been found
within the Zoophycos spreiten, hosted in the Guadalupian (Middle Permian) glaciomarine greywacke
of the Westley Park Sandstone Member within the Broughton Formation from the southern Sydney
Basin of southeastern Australia. They are composed of non-sheathed (PF1) and sheathed (PF2)
sub-micron balls, respectively. Chemically, the sub-micron balls consist of iron, sulphur, carbon and
oxygen. Both PF1 and PF2 occur in rhythmic alternationwithin the thick, light-grey and thin, dark-grey
minor lamellae of Zoophycos spreiten. The framboids from the minor lamellae are highly abundant and
occur in an orderly arrangement of equal density and in a good state of preservation.Within Zoophycos
spreiten no homogeneous filling, fecal pellets, or any sign of re-exploitation of the minor lamellae have
been recognized. No similar framboids have been observed outside Zoophycos spreiten. Therefore, the
framboids are interpreted as the pyritized remains of microbial colonies within Zoophycos spreiten.
The trace Zoophycos would be a multifunctional garden thatmay have been carefully constructed by the
Zoophycos maker, where different microbial colonies were orderly and carefully planted and cultured
within different minor lamellae. Further, it is proposed that the Zoophycos maker had a symbiotic
relationship with microbial colonies on the mutual basis of food supply and redox conditions. The fact
that the overlying spreiten cut the underlying ones indicates that the Zoophycos from the study area is
of an upward construction. The rhythmic alternation of both the thick, light-grey and thin, dark-grey
minor lamellae within Zoophycos spreiten may be suggestive of a gardening manner of the Zoophycos
maker responding to the warm and cold changes, food supply in pulses and variations of sedimentation
rate for planting and culturing microbial colonies under the conditions of a glaciomarine environment
at the high latitudes.

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This book discusses the contextual factors such as cultural and institutional settings that impact on effective people management practices in Asia. The challenges of multinational companies (MNCs) in the particular areas of attraction and retention, training and career development of the local skilled labour workforce are analyzed using the data of 529 MNCs in six Asian countries (namely Indonesia, Malaysia, Philippines, Singapore, Taiwan and Thailand). The degree of challenges varies by country and sector. This book draws conclusions from the empirical research stating that cultural and institutional theories, as well as the convergence and divergence theses can explain at best, partially, reasons behind the different outcomes of people management or human resource management (HRM) practices across MNCs in different operations in the region.

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Climate change is expected to have significant impacts on hydrologic regimes and freshwater ecosystems, and yet few basins have adequate numerical models to guide the development of freshwater climate adaptation strategies. Such strategies can build on existing freshwater conservation activities, and incorporate predicted climate change impacts. We illustrate this concept with three case studies. In the Upper Klamath Basin of the western USA, a shift in land management practices would buffer this landscape from a declining snowpack. In the Murray–Darling Basin of south-eastern Australia, identifying the requirements of flood-dependent natural values would better inform the delivery of environmental water in response to reduced runoff and less water. In the Savannah Basin of the south-eastern USA, dam managers are considering technological and engineering upgrades in response to more severe floods and droughts, which would also improve the implementation of recommended environmental flows. Even though the three case studies are in different landscapes, they all contain significant freshwater biodiversity values. These values are threatened by water allocation problems that will be exacerbated by climate change, and yet all provide opportunities for the development of effective climate adaptation strategies.

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This paper argues that gravity is often opposed to lightness in a conceptual manoeuvre reminiscent of the binaries of a metaphysics of presence (the latter as interrogated by Derrida; see generally 1997). In this paradigm, lightness operates akin to the ‘origin’ or presence, and is deemed to have been contaminated by the arrival of weight, the latter framed as threat to this (presence)/lightness. The paper challenges this conceptualisation, one that arguably dominates quotidian attitudes to the body and its movement capacities. It proposes instead that gravity can be read ‘deconstructively’—in other words, that lightness and weight emerge from and produce one another, and that weight always already operates, and therefore includes lightness. In order to inhabit this desiring-body (a body affected by gravity), particular framings of the body’s internal structures can permit a harnessing of gravity’s vectors of attraction, enabling what the author terms ‘a rigorous laziness’. The latter would involve both an initial attitude and a practice that eschews vocabularies of ‘force’ and ‘effort’, in favour of a ‘close reading’ of structural veracities, engaging strategically with, rather than against, them, in an approach akin to deconstruction’s reading along with a text. Drawing ekphrastically on the structural suggestiveness of Deleuze and Guattari’s rhizomatic and arborescent lenses, the paper finally contends that both these models are at work in human bodies, and that they operate in mutually generative ways. Taken up, this thinking may extend what the human body can do, and, most importantly, its pleasure in such doings.

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In group decision making (GDM) problems, ordinal data provide a convenient way of articulating preferences from decision makers (DMs). A number of GDM models have been proposed to aggregate such kind of preferences in the literature. However, most of the GDM models that handle ordinal preferences suffer from two drawbacks: (1) it is difficult for the GDM models to manage conflicting opinions, especially with a large number of DMs; and (2) the relationships between the preferences provided by the DMs are neglected, and all DMs are assumed to be of equal importance, therefore causing the aggregated collective preference not an ideal representative of the group's decision. In order to overcome these problems, a two-stage dynamic group decision making method for aggregating ordinal preferences is proposed in this paper. The method consists of two main processes: (i) a data cleansing process, which aims to reduce the influence of conflicting opinions pertaining to the collective decision prior to the aggregation process; as such an effective solution for undertaking large-scale GDM problems is formulated; and (ii) a support degree oriented consensus-reaching process, where the collective preference is aggregated by using the Power Average (PA) operator; as such, the relationships of the arguments being aggregated are taken into consideration (i.e., allowing the values being aggregated to support each other). A new support function for the PA operator to deal with ordinal information is defined based on the dominance-based rough set approach. The proposed GDM model is compared with the models presented by Herrera-Viedma et al. An application related to controlling the degradation of the hydrographic basin of a river in Brazil is evaluated. The results demonstrate the usefulness of the proposed method in handling GDM problems with ordinal information.