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1.
The first known ammonite from the Maastrichtian of the Perth Basin, a single, incomplete specimen of Grossouvrites gemmatus (Huppé, 1854), is described from core material from the Lancelin No. 1 borehole. Foraminiferal and nannoplankton evidence date the ammonite as middle Maastrichtian; its age is also assessed on the basis of dinoflagellate assemblages from this section, but these give a less precise dating. The position of the ammonite with respect to a mid-Maastrichtian disconformity, which probably extended along much of the Western Australian margin is discussed.  相似文献   

2.
Unconsolidated sediments from a borehole in Botany Bay have been analyzed for their foraminiferal content. Faunas from between 41 and 54 m below sea level are interpreted as Pleistocene in age. The foraminiferal assemblage from 54 m indicates marine conditions of moderately deep water (25–30 m), and a climate warmer than at present. The higher assemblages indicate a more brackish environment

The foraminifera, belonging to 123 species in 67 genera, are tabulated and 24 are discussed and illustrated. Three species, Oolina bifidocostata, Fissurina alatoquadrata and Elphidium botaniensis and one subpecies, Quinqueloculina affinis atrata, are described as new.  相似文献   

3.
The Stairway Sandstone is a 30–560 m thick succession of Middle Ordovician siliciclastic sedimentary rocks within the Amadeus Basin of central Australia, deposited in the epeiric Larapintine Sea of northern peri-Gondwana. The Stairway Sandstone is significant as one of only two known Gondwanan successions to yield articulated arandaspid (pteraspidomorph agnathan) fish. Herein we use the ichnology of the Stairway Sandstone to reveal insights into the shallow marine habitat of these early vertebrates, and compare it with that of other known pteraspidomorph-bearing localities from across Gondwana. The Stairway Sandstone contains a diverse Ordovician ichnofauna including 22 ichnotaxa of Arenicolites, Arthrophycus, Asterosoma, Cruziana, Didymaulichnus, Diplichnites, Diplocraterion, ?Gordia, Lockeia, Monocraterion, Monomorphichnus, Phycodes, Planolites, Rusophycus, Skolithos and Uchirites. These ichnofauna provide a well-preserved example of a typical Ordovician epeiric sea assemblage, recording the diverse ethologies of tracemakers in a very shallow marine environment of flashy sediment accumulation and regularly shifting sandy substrates. New conodont data refine the age of the Stairway Sandstone to the early Darriwilian, with ichnostratigraphic implications for the Cruziana rugosa group and Arthrophycus alleghaniensis.  相似文献   

4.
The Taebaeksan Basin occupies the central-eastern part of the Korean peninsula and was a low-relief shallow marine carbonate shelf on which the Cambro-Ordovician Choson Supergroup was deposited. In the Taebaeksan Basin trilobites are among the most dominant fossil groups in the Lower Ordovician, but they become less important in Middle Ordovician faunal assemblages. The Early Ordovician trilobite faunas of the Taebaeksan Basin are characterised by the common occurrence of pandemic genera such as Jujuyaspis, Leiostegium, Asaphellus, Protopliomerops, Hystricurus, Apatokephalus, Shumardia, Asaphopsoides, and Kayseraspis. Biogeographically significant trilobite taxa include Yosimuraspis, Dikelokephalina, Koraipsis, and Chosenia. These Ordovician trilobite faunas, which thrived in shallow marine environments, show a remarkable similarity with faunas from North China, implying that the Taebaeksan Basin was connected through contiguous shallow waters to North China. These Sino-Korean faunas exhibit a close biogeographic connection with Australian faunas, with which they share some endemic genera, whereas they are more distantly related to the faunas of South China, South America, and North America. Based on these palaeobiogeographical features, it is suggested that in the early Palaeozoic much of the present Korean peninsula including the Taebaeksan Basin belonged to the Sino-Korean block, while part of the peninsula was derived from the Yangtze block.  相似文献   

5.
Dermal denticles of two thelodont agnathans, Australolepis seddoni gen. et sp. nov., and a possible nikoliviid gen. et sp. indet. are described from the Gneudna Formation, a marine sequence of interbedded limestone and shale exposed on the eastern edge of the Carnarvon Basin, Western Australia. The age and significance of these new forms are discussed. The Gneudna Formation is Late Devonian, probably early Frasnian, which, if confirmed, makes these the youngest thelodonts known to date.  相似文献   

6.
A shallow marine faunule of eight taxa from the Kings Park Formation of the Perth Basin is the first described Paleocene molluscan assemblage from Western Australia. These species are part of a depauperate suite of macroinvertebrates (molluscs, echinoids and corals) derived from deep, onshore caissons in Perth and are inferred to be late Paleocene in age, based on planktonic foraminiferal biostratigraphy and associated age ranges of the molluscan fauna. Bivalves are Sarepta austranaxa sp. nov. (Sareptidae), Solemya kingsparki sp. nov. (Solemyidae), Periploma vivarirex sp. nov. (Periplomatidae), Parvamussium sp. nov.? (Propeamussiidae), Serripecten? sp. (Pectinidae) and Venericardia (Rotundicardia) petraea Darragh (Carditidae). Gastropods are Levifusus? sp. cf. L.? quadrifunifer Darragh (Buccinidae), and Columbarium rumatoides Darragh (Turbinellidae). Bivalves dominate the fauna in dark, glauconitic siltstone and sandstone facies; gastropods are of relatively poor preservation and low diversity.  相似文献   

7.
Although minor climatic and sea-level changes have been documented for the South Pacific during the late Holocene, our understanding of the consequent impact of these changes on the marine 14C reservoir, and therefore the 14C content of shellfish, is limited. Ultimately, this has implications for documenting the chronology of human movement and adaptation in this region. In this paper we compare marine reservoir (ΔR) data obtained from tightly controlled archaeological proveniences with known-age, pre-AD 1950 shells from the southern Cook Islands, American Samoa, and Marquesas Islands. Results indicate that there has been no significant change in the near-shore marine reservoir in these three locations over the last ca. 750 years. Furthermore, known-age, pre-AD 1950 shell samples provide more precise ΔR values for use in sample calibration than archaeological paired shell/charcoal samples. This is attributed in part to the limitations of assigning provenance and age to material from archaeological sites. On the basis of these results we conclude that the known-age, pre-AD 1950 shell derived ΔR values can be used to calibrate shell 14C results from deposits of late Holocene age.  相似文献   

8.
Fourteen Bivalvia species are described from the Lower Permian Río Genoa Formation, exposed in the southern Tepuel-Genoa Basin (Chubut Province, Argentina), of which one, Fletcheripecten genoensis, is new. The studied specimens are well preserved, retaining fine details of the ornament and shell morphology. Palaeotaxodonta is represented by two species of Nuculopsis and four species of Phestia; Pteriomorphia by five species in five genera; and Heteroconchia by three informal species. Most of the species recorded also occur in the northern part of Tepuel-Genoa Basin and allow demarcation of new and distinct marine intervals in the Río Genoa Formation, which was classically interpreted to represent continental deposits. The bivalve fauna confirms a Cisuralian (Early Permian) age for the Río Genoa Formation and offers potential for improved regional and global correlations.  相似文献   

9.
The brachiopod fauna from the Tupe Formation at La Herradura Creek, located on the west flank of Perico Hill, San Juan Province, Argentina, palaeogeographically belongs to the western sector of the Paganzo basin (‘Guandacol embayment’). The stratigraphical section of the Tupe Formation at La Herradura Creek is the stratotype of the Tivertonia jachalensis-Streptorhynchus inaequiornatus biozone, was previously regarded as being of Late Carboniferous age but here is assigned to the earliest Permian (Asselian). We describe and review the biozone assemblage, which consists of Streptorhynchus inaequiornatus, Tivertonia jachalensis, Kochiproductus sp., Costatumulus sp., Coronalosia argentinensis, Tupelosia paganzoensis, Trigonotreta pericoensis, Septosyringothyris sp. aff. Septosyringothyris jaguelensis and Crurithyris? sp. This brachiopod assemblage is related to Indian and Australian Early Permian faunas and its presence in the La Herradura Creek section provides new evidence in support of an Asselian (Early Permian) age for the Tivertonia jachalensis-Streptorhynchus inaequiornatus biozone. This assemblage is also important for intra- and inter-basinal correlation because several of its characteristic species have been identified from other sections of the Paganzo basin and the Río Blanco basin. The proposed age for this biozone is consistent with the age of palynological data from slightly above the marine faunas from the stratotype locality.  相似文献   

10.
Excavations in 1970, 1996, and 1999 at Site QJ-280, Quebrada Jaguay, in southern Peru, yielded enough dateable terrestrial plant material to establish an extensive radiocarbon chronology for the site. QJ-280 is one of oldest well-dated fishing sites in the Americas: it was occupied from the terminal Pleistocene to the mid-Holocene (about 13,000–8,300 calibrated years BP) based on 42 terrestrial radiocarbon dates, encompassing the Jaguay and Machas Phases of the local archaeological sequence. In addition to the terrestrial dates, radiocarbon measurements on valves of two marine surf clam (Mesodesma donacium) individuals from a single, well-dated mid-Holocene Manos Phase archaeological context have provided insight into marine upwelling conditions during the occupation of Quebrada Jaguay. The marine reservoir age varied between 130 and 730 14C years during the brief lives of the two clams (up to 5 years each), and varied by up to 530 14C years within an individual valve, suggesting strong and variable deep marine upwelling; conditions broadly similar to those that exist in coastal Peru today. These rapid variations in marine radiocarbon age suggest that marine radiocarbon dates from environments with variable upwelling could be skewed by up to hundreds of years.  相似文献   

11.
Mack, C.L. & Milne, L.A., 19.2.2015. Eocene palynology of the Mulga Rocks deposits, southern Gunbarrel Basin, Western Australia. Alcheringa 39, xxx–xxx. ISSN 0311-5518

Late Eocene palynomorph assemblages have been recovered from carbonaceous sediments within a tenement centred on the Mulga Rocks uranium deposits, currently under exploration by Energy and Minerals Australia. The Mulga Rocks deposits occur in a palaeovalley incised into rocks of the Cretaceous southern Gunbarrel Basin, and the underlying Neoproterozoic to Late Devonian southern Officer Basin, Western Australia. The palynomorph assemblages recovered from the Mulga Rocks deposits most closely resemble the Middle Nothofagidites asperus Zone equivalent of the Murray Basin. Many of the species recovered, and the abundance and diversity at which they are present, are considerably different from most of the southeastern Australian palynoassemblages of similar age. Common in the assemblages are species belonging to Nothofagus, Casuarinaceae, Myrtaceae and Picrodendraceae. Proteaceous species are diverse, with Banksia affiliates being prominent. Of most significance are assemblages dominated by Myrtaceidites species, which also contain affiliates of Petrophile and Xylomelum that occur in modern heathland, woodland and dry sclerophyll forests. The prominence of these taxa, and their co-occurrence, suggests that sclerophylly, at present linked closely with xeromorphy and now ubiquitous in the vegetation of Western Australia, was present in the late Eocene of southern Australia and suggests that at that time this trait may have been more prevalent than previously interpreted.

Charlotte Mack [ and Lynne Milne [], Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, WA 6845, Australia. Received 4.7.2014; revised 11.2.2015; accepted 19.2.2015.  相似文献   

12.
A new faunal assemblage is reported from the Tempe Formation (Cambrian Series 2, Stage 4; Ordian) retrieved from the Hermannsburg 41 drillcore, Amadeus Basin, central Australia. Two trilobite taxa, including one new species Gunnia fava sp. nov., four brachiopod taxa, including the age-diagnostic Karathele napuru (Kruse), Kostjubella djagoran (Kruse) and Micromitra nerranubawu Kruse, together with a bradoriid, helcionellids, hyoliths, echinoderms, chancelloriids, sponges and problematic tubes are described. The fauna has close links to those of the neighbouring Daly, Georgina and Wiso basins and suggests that the Tempe Formation correlates with the Australian Ordian stage (either the Redlichia forresti or Xystridura negrina assemblage zones). The Giles Creek Dolostone in the eastern Amadeus Basin, previously regarded as coeval with the Tempe Formation, has recently been reported to be of early Templetonian age in its type section. The described taxa from the Tempe Formation confirm that these two sedimentary units are not contemporaneous and that regional stratigraphic schemes should be amended.  相似文献   

13.
Schmidt, R., March 2007. Australian Cenozoic Bryozoa, 2: Free-living Cheilostomata of the Eocene St. Vincent Basin, S.A., including Bonellina gen. nov. Alcheringa 31, 67-84. ISSN 0311-5518.

Free-living bryozoans are diverse in the Eocene sediments of the St. Vincent Basin, South Australia. They include Bonellina pentagonalis gen. et sp. nov., Otionellina sp. cf. O. exigua (Tenison Woods), Otionellina sp. cf. O. cupola (Tenison Woods), Tubiporella magna (Tenison Woods), Celleporaria nummularia (Tenison Woods), and an indeterminate species only found as moulds. This diversity and abundance is highest in the sediments representing the initial transgressive marine facies, where they occur in ‘sand fauna’ bryozoan assemblages (e.g. with Melicerita and Siphonicytara). Free-living bryozoans decrease up-section and are absent from latest Eocene sediments, indicating a significant environmental shift.

Rolf Schmidt [rschmid@museum.vic.gov.au], Museum Victoria, Melbourne, Vic 3001, Australia; received 18.3.2005, revised 14.12.2005.  相似文献   

14.
Tivertonia yarrolensis from the Farley Formation of the Sydney Basin is illustrated for the first time. The age of the formation is discussed. The palaeogeographical distribution of Tivertonia provides an additional generic link within the Austrazean Province of the Gondwanan Realm.  相似文献   

15.
The five known species of pentameride brachiopods from the Yass Syncline Ludlow (LateSilurian) succession, belonging to the superfamilies Pentameroidea, Gypiduloidea and Clorindoidea, are fully revised; no new species are recognised. The pentameroids Conchidium sp. cf. hospes and Aliconchidium yassi are confined to the Bowspring Limestone Member (Silverdale Formation). The gypiduloid Ascanigypa glabra and externally homeomorphic clorindoids Barrandina wilkinsoni and Clorinda minor replace them in the overlying Barrandella Shale Member, the last two extending into the Yarwood Siltstone Member (Black Bog Shale). Clorinda minor is also possibly present in the Rainbow Hill Member (Rosebank Shale). All except C. minor are uncommon to rare components of the Yass brachiopod fauna. Clorinda molongensis, a species of uncertain mid- to late Silurian age from the Molong Limestone, is also revised. Aliconchidium and Barrandina are known only from Yass, whereas Clorinda is cosmopolitan. Conchidium alsois widespread, but C. hospes is a species from the Prague Basin probably also known from the Urals and the Tien Shan. Ascanigypa is another Prague Basin taxon, recently recognised in Arctic Canada.  相似文献   

16.
Brachiopods of the Marginirugus barringtonensis and Levispustula levis Zones comprise the youngest of three major Carboniferous biostratigraphic units in eastern Australia. The remarkable change in the composition of marine invertebrates between the second and third of these units, a transition that only two brachiopod species are known to survive, has been attributed to the isolation of eastern Australia and to a drop in temperature. The Marginirugus barringtonensis and Levipustula levis Zones are redefined from reference sections in the Myall region, N.S.W.; the L. levis Zone now includes the Syringothyris bifida Zone of Campbell (1961). Faunal sequences show that these two zones are closely related and that there is no hiatus between them, as formerly proposed by McKellar (1965). Conodonts identified by Mr. D. Crane indicate a late Viséan to early Namurian age for the Marginirugus barringtonensis Zone, and an age of early Namurian for the base of the Levipustula levis Zone; brachiopod evidence indicates that the L. levis Zone extends into the Westphalian. The younger Auriculispina levis Zone from the Yarrol Basin may be coeval with the Trigonotreta campbelli Zone from N.S.W. Faunas from both the L. levis and A. levis Zones are present in Argentina and many species from the L. levis Zone have affinities with forms from the Baikal region, U.S.S.R. Correlations based on the zones have eliminated the need for a hiatus between the Branch Creek and Baywulla Formations in the Yarrol Basin.

Taxa described from the Marginirugus barringtonensis and Levipustula levis Zones in the Myall region include Yagonia gibberensis Roberts gen. et sp. nov., Bulahdelia myallensis Roberts gen. et sp. nov., Alispirifer yagonensis Thompson sp. nov., A. alatus Thompson sp. nov., Licharewia bootiensis Thompson sp. nov., Spirifer pristinus (Maxwell), Spiriferi sp., Neospirifer campbelli Maxwell and N. senilis Maxwell.  相似文献   

17.
The hunting of Gazella subgutturosa was a dominant practice for Epipalaeolithic and early Neolithic hunter–gatherers in the east Jordan steppe. The seasonal mobility of this taxon in the Levant is poorly understood, especially for early prehistory when herd movements would have influenced hunter-gatherer use of the steppes. This paper proposes four patterns of seasonal herd mobility for G. subgutturosa centred on Jordan’s Azraq Basin. The four patterns are modelled using oxygen, carbon and strontium stable isotopes. Seasonal environmental signatures of each are understood through carbon and strontium isotopic variation in sixty modern plant specimens collected from twelve selected locations in north Jordan, published data on oxygen isotopes in local precipitation, and the adaptive behaviour of G. subgutturosa. The integrated isotopic datasets provide clear discriminatory markers for each proposed mobility pattern. Results will be applied in future to isotopic data from archaeological gazelle teeth from the Azraq Basin.  相似文献   

18.
Seven species of marine bivalves, including six new taxa, are described from the Cape early Miocene Melville Formation which crops out on the Melville Peninsula, King George Island, West Antarctica. The bivalve assemblage includes representatives of the families Nuculidae, Ennucula frigida sp. nov., E. musculosa sp. nov.; Malletidae, Neilo (Neilo) rongelii sp. nov.; Sareptidae, Yoldia peninsularis sp. nov.; Limopsidae, Limopsis psimolis sp. nov.; Hiatellidae, Panopea (Panopea) sp. cf. P. regularis; and Pholadomyoida (Periploma acuta sp. nov.). Species studied come from four sedimentary sections measured in the upper part of the unit. Detailed morphologic features of nucloid and arcoid species are exceptionally well preserved and allow for the first time reconstruction of muscle insertions as well as dentition patterns of Cenozoic taxa. Known geological distribution of the species is in agreement with the early Miocene age assigned to the Cape Melville Formation. The bivalve fauna from Cape Melville Formation is the best known from Antarctic Miocene rocks, a time of complex geologic, paleogeographic and paleoclimatic changes in the continent. The new fauna introduces new taxonomic and palaeogeographic data that bear on the question of opening of sea gateways and distribution of Cenozoic biota around Antarctica.  相似文献   

19.
Phosphatic stromatolites from the early Middle Cambrian (Ordian) of the Georgina Basin are described and identified as Ilicta cf. composita Sidorov. Based on Öpik's interpretation of the early Middle Cambrian, the age of the Georgina Basin specimens is similar to that of the type specimens described from the late Early Cambrian of Eastern Siberia. Phosphatic stromatolites occur at the base of dolomitized and partially silicified bioherms up to 4 m thick. The phosphatic forms overlie impermeable, cemented pavement surfaces which were covered by stratiform stromatolites from which rose columnar forms up to 5 cm in height. The stromatolites were phosphatized by penecontemporaneous diagenetic reactions that took place just below the sediment water interface and above the impermeable substrates.  相似文献   

20.
The Ordovician diversification is marked by an increase in both marine diversity and ecospace occupation. Bivalves, like other groups, underwent a remarkable diversification in the Early Ordovician. The early phases of such a bivalve diversification took place in the Gondwanan basins of western Argentina. In the Northwestern Argentina (NWA) Basin, three clades originated during late Tremadocian–Floian times. In the Floian successions of the Famatina Basin, a probable basal arcoid is recorded. Genera from these two basins belong to 13 families. Phylogenetic analysis of the NWA heteroconchian bivalves indicates that redoniids and coxiconchinids may have originated during this radiation event. This taxonomic radiation also implies an ecological diversification. Ten guilds are recognized on the basis of bauplan, mode of life, and feeding types. Lifestyles included free endofaunal, free semi-endofaunal, semi-endobyssate, and epibyssate; feeding types included suspensivorous and detritivorous habits. Physiological changes imposed by colonization of low-salinity environments also account for guild definitions. Recent discoveries of Tremadoc to early Darriwilian bivalves from the NWA and Famatina basins indicate that the dominance of higher groups (e.g. Heteroconchia, Pteriomorphia) deviates from the patterns evident in other Gondwanan basins. This agrees with previous ideas supporting the importance of local radiations during the Ordovician diversification. Two new taxa are described, Eoredonia orientalis gen. et sp. nov. and Babinka notica sp. nov., and Coxiconchia sellaensis Sánchez & Babin is first reported from the NWA Basin.  相似文献   

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