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The discovery of a rich assemblage of microfossils from the Neoproterozoic western Officer Basin (Centralian Superbasin) provides a more complete understanding of the biostratigraphy of this Basin. The microfossils are found in Supersequence 1 (~800 Ma) in Western Australia. The assemblages are comprised of acritarchs and cyanobacteria isolated by acid maceration from siliciclastics of the Browne (Madley), Hussar, Kanpa and Steptoe Formations. The distinctive acritarchs Cerebrosphaera buickii, Satka colonialica, Stictosphaeridium sinapticuliferum and Pterospermopsimorpha insolita are of particular interest in the Neoproterozoic. These taxa are found in similar depositional environments in Spitsbergen, Arizona, Canada and Siberia. This evidence, together with lithostratographic correlations, isotope chemostratigraphy, and sequence analysis contributes to the continuing development of Neoproterozoic stratigraphy.  相似文献   
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Microfossil assemblages are described from the early Neoproterozoic Madley and Browne Formations, western Officer Basin. One chert and eleven siliciclastic samples yielded microfossils. Myxococcoides cantabrigiensis occurs as pustular mats in the chert sample and Eomicrocystis malgica, Pterospermopsimorpha granulata, Skiagia sp. cf. S. pusilla, and undetermined species of Obruchevella, Heliconema, and Trachystrichosphaera are present in acid macerated samples. Leiosphaeridia spp. and Siphonophycus spp. are also found in fine-grained siliciclastic samples, with clusters of Synsphaeridium sp. in some samples. These findings enable a more substantial reconstruction of the palaeoenvironment of Supersequence 1 in the western Centralian Superbasin. The acanthomorph acritarchs are considered to be planktonic eucaryotes washed into environments which ranged from coastal sabkha through to tidal flats, which may be the source of the prokaryotic, benthic, matforming cyanobacteria.  相似文献   
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The Palace of Westminster is in need of urgent, substantial repairs. This provides a ‘window of opportunity’ for change. This essay traces the restoration and transformation (or lack of) that the Palace of Westminster has seen in the last half a century, before assessing its current state, and considering whether parliament is fit for purpose. It provides a ‘long‐view’ understanding of previous missed ‘windows of opportunity’. The essay focuses on drawing insights from history in order to add a depth of understanding to the contemporary issue. An understanding of the preceding renewal and restoration projects enables us, potentially, to avoid some of the problems that have been previously experienced, and finally seize this opportunity to build a parliament which is fit for purpose.  相似文献   
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Historical Archaeology -  相似文献   
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