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31.
Alex G. Cook Robert B. Blodgett R. Thomas Becker 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):181-207
Over 50 identifications of Tertiary pollen are reviewed. The pollen assemblages indicate rain-forest through most of the Tertiary, but the requisites for pollen preservation are biased towards the wetter climates. The present day geographical affinities of the botanical groups are largely with taxa of the tropical zone and Australia-wide taxa. There is geographic variation in the fossil pollen assemblages when southeastern Australia is compared with Central Australia and Queensland. The major changes in the fossil floras coincide with climatic change, indicating the influence of climate on the evolution of plant assemblages. The older phytogeographic concepts are inappropriate for the fossil record, especially when considered in conjunction with palaeoclimates and palaeogeography. It is unfortunate that palynology has given little information of the evolution of floras in drier climatic regimes, or of the evolution of the eucalypts. 相似文献
32.
Josefina Carlorosi Susana Heredia Guillermo Aceñolaza 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):299-311
Carlorosi, J., Heredia, S. & Aceñolaza, G, 2013. Middle Ordovician (early Dapingian) conodonts in the Central Andean Basin of NW Argentina. Alcheringa 37, 1–13. ISSN 0311-5518. This paper describes and analyzes the significance of a conodont fauna from the Alto del Cóndor Formation, exposed in the Los Colorados region of the Argentine Eastern Cordillera. Identified taxa are Baltoniodus triangularis, Baltoniodus sp. cf. B. triangularis, Drepanodus sp., Drepanoistodus basiovalis, Drepanoistodus sp. B., Erraticodon patu, Gothodus costulatus, Oistodus sp., Trapezognathus diprion, T. quadrangulum, Triangulodus sp. and Triangulodus? sp. The presence of Baltoniodus triangularis indicates the base of the Dapingian stage (Middle Ordovician). In addition, we report the coexistence of T. diprion and T. quadrangulum. The conodont association suggests a faunal affinity with Baltica and South China, both belonging to the Shallow-Sea Realm of the Temperate-Cold Domain. Josefina Carlorosi [josefinacarlorosi77@gmail]com], INSUGEO—Universidad Nacional de Tucumán—CONICET, Miguel Lillo 205, (4000) Tucumán, Argentina; Guillermo F. Aceñolaza [acecha@webmail.unt.edu.ar], Universidad Nacional de Tucumán—CONICET, Miguel Lillo 205, (4000) Tucumán, Argentina; Susana Heredia [sheredia@unsj.edu.ar], CONICET–CIGEOBIO and Instituto de Investigaciones Mineras, Facultad de Ingeniería, Universidad Nacional de San Juan, Urquiza y Libertador, (5400) San Juan, Argentina. Received 22.8.2012; revised 18.10.2012; accepted 24.10.12. 相似文献
33.
Daniel L. Thompson 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):345-357
The brissid echinoid Schizobrissus insignis (Duncan &; Sladen, 1883) is described from the Fulra Limestone (late middle Eocene), in Kachchh, India. Formerly assigned to Peripneustes or to Meoma it is shown that the species possesses a complete subanal fasciole throughout ontogeny, a characteristic feature of Schizobrissus. Eocene species of Schizobrissus and Meoma show several morphological similarities, but diverged during the late Paleogene and early Neogene. 相似文献
34.
Proterosuchid archosaur remains from the Early Triassic Bulgo Sandstone of Long Reef,New South Wales
Benjamin P. Kear 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):331-337
Two associated anterior dorsal vertebrae of a primitive archosaur are described from the Early Triassic (Dienerian–Spathian) Bulgo Sandstone at Long Reef, New South Wales, Australia. Character states including anteroposteriorly elongate centra, dorsal neural spines with height greater than length, the possible presence of intercentra, double-headed rib articulations and well-developed apical tables on the neural spines suggest affinity with proterosuchid archosauriforms and permit some comparisons with previously described Australian taxa. The Bulgo Sandstone vertebrae represent the first record of archosaurian body fossils from the Sydney Basin and are one of only a handful of occurrences thus far documented from the Triassic of Australia. 相似文献
35.
C. C. Wainman C. Hannaford D. Mantle P. J. McCabe 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):402-414
Wainman, C.C., Hannaford, C., Mantle, D. & McCabe, P.J., April.2018. Utilizing U–Pb CA-TIMS dating to calibrate the Middle to Late Jurassic spore-pollen zonation of the Surat Basin, Australia to the geological time-scale. Alcheringa XX, xx-xx.Spore-pollen palynostratigraphy is commonly used to subdivide and correlate Jurassic continental successions in eastern Australia and thus aid the construction of geological models for the petroleum and coal industries. However, the current spore-pollen framework has only been tenuously calibrated to the geological time-scale. Age determinations are reliant on indirect correlations of ammonite and dinoflagellate assemblages from New Zealand, the North West Shelf of Australia and Southeast Asia to the standard European stages. New uranium-lead chemical abrasion thermal ionization mass spectrometry (U–Pb CA-TIMS) dates from 19 tuff beds in the Middle–Upper Jurassic Injune Creek Group of the Surat Basin enables regional spore-pollen palynostratigraphic zones to be precisely dated for the first time. These results show the base of the APJ4.2 and APJ4.3 subzones are similar in age to previous estimates (Middle Jurassic, Bathonian) from indirect palynostratigraphic correlation. However, the base of the APJ5 Zone and the APJ6.1 Subzone may be somewhat younger than previously estimated, possibly by as much as 2.5 and 4.2 Myrs, respectively. The continued utilization of U–Pb CA-TIMS dates will further refine the absolute ages of these zones, improve the inter- and intra-basinal correlation of Middle–Upper Jurassic strata in eastern Australian basins and greatly enhance intercontinental correlations.Carmine Christopher Wainman [carmine. wainman@adelaide. edu. au] and Peter James McCabe [peter. mccabe@adelaide,edu. au] Australian School of Petroleum, University of Adelaide, SA, 5005, Australia; Carey Hannaford [carey. hannaford@mgpalaeo. com. au] and Daniel Mantle [dan. mantle@mgpalaeo. com. au] MGPalaeo Pty Ltd, 5 Arvida Street, Malaga, WA, 6090, WA, Australia. 相似文献
36.
M. Lucía Balarino 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):317-337
The first palynozonation for Permian strata of the Claromecó Basin (Argentina) is formally proposed, based on palynological assemblages recovered from the UTAL.CMM1 La Estrella.x-1 and UTAL.CMM1 Cruz de Sur.x-1 boreholes, drilled on the Argentinian Continental Platform and correlation with established zones from neighbouring basins. Fifty-five samples were analyzed and 131 species identified from two biozones. The lower Converrucosisporites confluens–Vittatina vittifera (CV) Zone occurs in the Piedra Azul and Bonete formations of both boreholes. This zone can be assigned a Cisuralian–Guadalupian age. The upper Tornopollenites toreutos–Reduviasporonites chalastus (TC) Zone registered in the Tunas Formation can be assigned a Guadalupian–Lopingian age. The CV Zone is dominated by diverse non-taeniate bisaccate, plicate and taeniate pollen. Monosaccate and monosulcate pollen, algae and acritarchs are poorly represented in both biozones. The composition of the TC Zone is broadly similar to the CV Zone, but bisaccate pollen grains are markedly more diverse and abundant in the former. 相似文献
37.
Amit K. Ghosh Ratan Kar Reshmi Chatterjee 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):92-98
Disc-like galls are reported on the Triassic corystosperm leaf Dicroidium hughesii (Feistmantel) Lele from the Parsora Formation of South Rewa Gondwana Basin, central India. Although there have been numerous reports of arthropod–plant interactions from Permian and Lower Cretaceous successions, this is the first unequivocal report of arthropod–plant interactions from the Triassic succession of Peninsular India. The new record adds to global evidence that arthropod herbivory and gall formation, in particular, had rediversified by the Late Triassic in the wake of the end-Permian mass extinction. 相似文献
38.
R.E. Wass 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):41-48
Examples of early astogeny in the species Carinatocella harmeri (Stach), Costaticella hastata (Busk) and Claviporella aurita (Busk) are discussed. The primary zoid differs in each species and if found fossil, only in C. hastata could this zoid be recognised as a bryozoan fragment. Analogous development in other Bryozoa is discussed. 相似文献
39.
Geoffrey Playford Francine Martin 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):187-223
A left mandibular toothplate of a chimaeroid fish collected from the Toolebuc Formation (Early Cretaceous, Albian), central Queensland is described. Comparisons with other chimaeroid genera show the toothplate to be sufficiently distinct to warrant the erection of a new genus. Ptyktoptychion tayyo gen. et sp. nov. is distinguished by the size and shape of its three tritors, the form of the symphysial facet and the overall shape of the toothplate. 相似文献
40.
黑河流域居民生活质量研究 总被引:1,自引:0,他引:1
以《Calvert-Henderson生活质量指标》一书为理论指导构建了生活质量评价指标体系,通过开展生活质量问卷调查及查找相关统计资料,运用主成分分析法确定指标的权重,研究了我国西北地区第二大内陆河流域-黑河流域城乡居民2004年的生活质量。具体的评价结果是:黑河流域城镇居民生活质量明显高于农村;黑河流域城市居民生活质量表现出中游高于上游和下游;黑河流域农村居民生活质量以乡镇为单位计算差异显著;黑河流域农村居民生活质量中游略好于上游、下游;影响黑河流域城乡居民生活质量的主要因素是收入、教育和住房。 相似文献