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31.
A Buddhist temple in Berkeley, Wollongong, may at first appear puzzling given that few Buddhists lived there. Indeed, the suburb was home to predominantly those Anglo-Celtic Australians most marginalised by the structural changes to the city's economic base. This problem is explored within the social dynamics of inclusion and exclusion operating within the local politics of place-making. Drawing upon the concept of a progressive sense to place revealed that discourses of support for the temple drew heavily on imagining Australia and Wollongong as multicultural and the temple as an exotic object of the Orient, worthy of tourist visitation. A Buddhist temple provided the city with a source of cultural vitality and enrichment. Imagined as a tourist attraction, a place to visit, rather than as sacred space, a place to worship, a Buddhism sect was perhaps in this way made less threatening to local Christian residents. These results further support arguments that suggest a redundancy to the fixed notions of place as bounded territory and how territorial rules that define whether something, or someone, is appropriately placed requires interrogating the connectedness between social powers and the powers of place.  相似文献   
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Irregular and discontinuous coalified objects, here termed rhizomorphs, occur above the Summum (No. 4) Coal Member (Carbondale Formation) at one locality in La Salle County, Illinois. These vitrinite structures, varying between 3 mm and 4 cm in diameter, occur in a blocky to structureless mottled claystone characterized by numerous carbonaceous streaks and small-scale slickensides. The rhizomorphs twist and bend in a tightly coiled and kinked pattern, and may extend laterally through the claystone for 40 cm or more before bifurcating or terminating. The rhizomorphs display little or no evidence of compressive distortion. They are composed of two types of material: structureless bright conchoidal collinite; and cellular woody structure. One or more vascular bundles occur as discrete steles within a groundmass of collinite gel; these are generally aligned longitudinally within the coal except where steles diverge laterally as offshoots. The rhizomorphs are believed to be a diagenetic derivative of rooting structures; this is based on their occurrence in an underclay-like sediment and on their irregular, kinked form, which differs from that of most vertical supportive plant stems. Non-compressive coalification of the plant material may have occurred through: (1) aerobic alteration of cell walls to non-compressive inertinite; (2) centripetal contraction and selective degradation of plant tissue; and (3) impregnation of more resistant stelar elements by organic gel derived from degradation of thin-walled tissue.  相似文献   
34.
The Cambro-Ordovician Cap Enragé Formation is interpreted as a deep submarine channel complex of conglomerates, pebbly sandstones and massive sandstones. The formation is up to 270 m thick, and crops out in a coastal belt 50 km long. In general terms, it has previously been interpreted as a deep sea channel deposit, with the channel about 300 m deep, at least 10 km wide and trending south-westward, parallel to the coastal outcrops. Eight facies have been defined in this study and they have been grouped into three major facies associations. In the Coarse Channelled Association, conglomerates with carbonate boulders up to about 4 m are associated with graded-stratified finer grained conglomerates. Facies of this association make up about 25% of all the beds in the formation. The association is also characterized by abundant major channels 1–10 m deep and up to 250 m wide. Excellent outcrop allows the reconstruction of topographic highs (bars) within the channels and the association is interpreted as a braided channel and bar system. The second association, Multiple-Scoured Coarse Sandstones, contains some graded-stratified fine conglomerates, along with massive to structureless coarse and pebbly sandstones, and rare cross-bedded pebbly sandstones. Deep channels are absent, but multiple channelling on the scale of 0.5–1 m is characteristic. In the absence of the very coarse conglomerates and deeper channelling, this association is interpreted as being deposited on topographically higher terrace areas adjacent to the main braid plain. The third facies association, Unchannelled Sandstones, is characterized by massive sandstones with abundant fluid-escape structures, classical turbidites and thin shales. In the absence of any scouring deeper than a few tens of centimetres, this association is interpreted as being deposited on an even higher and smoother terrace, farther from the braid plain. Palaeoflow directions for conglomerate facies indicate fairly consistent south-westward transport, apparently parallel to the base of the Cambro-Ordovician continental slope. Flow directions in the finer-grained facies are rather variable, suggesting complex bar development and overbank spills. Thinning-and fining-upward sequences are present on two scales. The smaller, 1–10 m sequence, is related to channel filling and abandonment. Thicker sequences (10–100 m), with facies of the Multiple Scoured, and Unchannelled Sandstone Associations, may indicate switching of a main channel away from the area and its subsequent burial by marginal terrace and higher terrace deposits.  相似文献   
35.
The deep-tow instrument package of Scripps Institution of Oceanography provides a unique opportunity to delineate small-scale features of a size comparable to those features usually described from ancient deep-sea fan deposits. On Navy Fan, the deep-tow side-scanning sonar readily detected steep channel walls and steps and terraces within channels. The most striking features observed in side-scan are large crescentic depressions commonly occurring in groups. These appear to be large scours or flutes carved by turbidity currents. Four distinct acoustic facies were mapped on the basis of qualitative assessment of reflectivity of 4 kHz reflection profiles. There is a distinct increase in depth of acoustic penetration, number of sub-bottom reflectors, and reflector continuity from the upper fan-valley to the lower fan. These changes are accompanied by a decrease in surface relief. Navy Fan is made up of three active sectors. The active upper fan is dominated by a single channel with prominent levees that decrease in height downstream. The active mid-fan region or suprafan is where sand is deposited. Well defined distributary channels with steps, terraces, and other mesotopography terminate in depositional lobes. Interchannel areas are rough, containing giant scours as well as other relief. The active lower fan accumulates mud and silt and is without resolvable surface morphology. The morphological features seen on Navy Fan other than levees, interchannel areas, and lobes are principally erosional. The distributary channels are up to 0.5 km wide and 5–15 m deep. Such features, because of their large size and low relief, are rarely completely exposed or easily detectable in ancient rock sequences. Some flute-shaped scours are larger than channels in cross section but many are 5-30 m across and 1-2 m deep. If observed in ancient rocks transverse to palaeo-current direction, they would perhaps be indistinguishable from channels. Surface sediment distribution combined with fan morphology can be used to relate modern sediments to facies models for ancient fan sediments. Gravel and sand occur in the upper valley, massive sand beds in the mid-fan distributary channels, classical complete Bouma sequences on depositional lobes, incomplete Bouma sequences (lacking division a) on the lower mid-fan, and Bouma sequence with lenticular shape or other limited extent on mid-fan interchannel areas and on levees.  相似文献   
36.
Pollen-stratigraphic evidence is presented from a site in the Grampian Highlands of Scotland in which a detailed record is preserved of early Postglacial plant succession in an area previously occupied by glacier ice. Following an initial period of open habitat conditions during which sedge-moss communities were interspersed with large areas of bare, disturbed ground, the area around the site was colonised first by Empetrum heath, and then successively by juniper scrub, birch, and then birch-hazel woodland. On a local scale, the biostratigraphic record implies a rapid shallowing of lake waters during the early Postglacial, due possibly to relatively dry climatic conditions which prevailed in the area after ca. 9000 B.P. Radiocarbon dates were obtained from the basal sediments in the site, but these are regarded as aberrant due to groundwater contamination. In view of the poor resolution associated with the radiocarbon-dating of Lateglacial and early Flandrian events in Britain, a method is proposed here whereby pollen stratigraphic evidence at widely separated sites can be employed to gauge the extent to which deglaciation at the end of the Loch Lomond (Younger Dryas) Stadial was time-transgressive across the Highlands of Scotland  相似文献   
37.
Facies relationships in Pleistocene braided outwash deposits in southern Ontario demonstrate the presence of a large braid bar with adjacent side channel. The core of the bar is up to 6 m high, and consists of crudely horizontally stratified gravels. Downstream from the core is the bar front facies, consisting of large gravelly foresets up to 4 m high, rounded off in many places by reactivation surfaces. Upstream from the core is the bar stoss side facies consisting of several sets (individually up to 35 cm thick) of tabular cross-bedding, arranged in coarsening-upward sequences. The stoss side—core—bar front relationships are continuously exposed in one 400 m long quarry face which is cut almost parallel to the palaeoflow direction. A transverse quarry face shows the side channel facies, which consists of trough cross-bedded sands. Gravel layers can be seen to finger from the main gravelly bar into the sandy side channel, but they do not reach the base of the channel. This surprising relationship indicates that gravel moved only in the topographically higher parts of the system. After deposition in the side channel, and growth upstream and downstream from the bar core, the entire system aggraded. Crudely horizontally stratified, and imbricated gravel sheets were laid down as a bar top facies. Grain size analyses indicate strongly bimodal distributions, implying that much of the sand in the spaces between pebbles and boulders filtered in after the gravel had been deposited. This interpretation is strengthened by velocity calculations—mean velocities in excess of 300 cm/s would be needed to roll the gravel as bed load, but at such a velocity, a large amount of sand would be transported entirely in suspension. In a final section of the paper, our results are combined with other work on braided systems in an attempt to formulate a more general facies model.  相似文献   
38.
Miocene volcanism in the Blue Mountains province of centralOregon produced diverse basaltic rocks. One set of these, thePicture Gorge Formation of the Columbia River Basalt Group,is well known. Others (Bowman Dam, Bear Creek, and Slide Creekflows) are relatively poorly known. Only the Picture Gorge flowsin the center of the province are typical continental floodbasalts. Basaltic rocks with calc-alkaline affinities (evolvedBear Creek flows, Slide Creek basalts) are found to the westand east. Basal Bear Creek flows closely resemble MORB and islandarc tholeiites, despite having erupted on a continental plate.Bowman Dam (formerly ‘Prineville’) basalts are richin K2O, P2O5, and Ba, and poor in Ni, Co, and Cr. Some of thesefeatures may reflect mantle metasomatism or crustal contamination.Thus, several currently debated theories of basalt petrogenesiscan be tested by studying flows erupted during Miocene timesin this relatively small area. Very few, if any, of these basaltic rocks represent primarymantle-derived magmas. Inferred depths of the pre-eruption magmareservoirs in which they were fractionated are shallow in thecenter of the province, deeper to the east and west. The E-W axis of Miocene calc-alkaline rocks in the Blue Mountainsprovince existed simultaneously with a N-S axis of calc-alkalineactivity in the Cascades that paralleled an offshore subductionzone. Current ideas of relationships among tectonic settingsand the compositions of volcanic rocks cannot easily be madeto conform with these facts.  相似文献   
39.
Mafic tholeiitic basalts from the Nejapa and Granada (NG) cindercone alignments provide new insights into the origin and evolutionof magmas at convergent plate margins. In comparison to otherbasalts from the Central American volcanic front, these marietholeiitic basalts are high in MgO and CaO and low in Al2Op,K2O1, Ba and Sr. They also differ from other Central Americanbasalts, in having clinopyroxene phenocrysts with higher MgO,CaO and Cr2O3 concentrations and olivine phenocrysts with higherMgO contents. Except for significantly higher concentrationsof Ba, Sr and 87Sr/86Sr, most of the tholeiites are indistinguishable in compositionfrom mid-ocean ridge basalts. In general, phenocryst mineralcompositions are also very similar between NG tholeiites andmid-ocean ridge basalts. The basalts as a whole can be dividedinto two groups based on relative TiO2-K2O concentrations. Thehigh-Ti basalts always have the lowest K2O and Ba and usuallyhave the highest Ni and Cr. All of the basalts have experienced some fractional crystallizationof olivine, plagioclase and clinopyroxene. Relative to otherCentral American basalts, the Nejapa-Granada basalts appearto have fractionated at low PT and PH2O. The source of primarymagmas for these basalts is the mantle wedge. Fluids and/ormelts may have been added to the mantle wedge from hydrothermally-altered,subducting oceanic crust in order to enrich the mantle in Sr,Ba and 87Sr/86Sr, but not in K and Rb. The role of lower crustaicontamination in causing the observed enrichments in Sr, Baand 87Sr/86Sr of NG basalts in comparison to mid-ocean ridgebasalts, however, is unclear. Rutile or a similar high-Ti accessoryphase may have been stable in the mantle source of the low-TiNG basalts, but not in that of the high-Ti basalts. Mafic tholeiiticbasalts, similar to those from Nejapa and Granada, may representmagmatic compositions parental to high-Al basalts, the mostmafic basalts at most Central American volcanoes. The characterof the residual high-Al basalts after this fractionation stepdepends critically on PH2O Both high and low-Ti andesites are also present at Nejapa. Likethe high-Ti basalts, the high-Ti andesites have lower K2O andBa and higher Ni and Cr in comparison to the low-Ti group. Thehigh-Ti andesites appear to be unrelated to any of the otherrocks and their exact origin is unknown. The low-Ti andesitesare the products of fractional crystallization of plagioclase,clinopyroxene, olivine (or orthopyroxene) and magnetite fromthe low-Ti basalts. The eruption that deposited a lapilli sectionat Cuesta del Plomo involved the explosive mixing of 3 components:high-Ti basaltic magma, low-Ti andesitic magma and high-Ti andesiticlava.  相似文献   
40.
Abstract

An inductive learning capability has been interfaced to a computerized geographical modelling package. The capabilities of the integrated system, called SIMPLE, are described. The use of the system to model and map the distribution of kangaroo populations is briefly described.  相似文献   
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