COOL-WATER CARBONATE SEDIMENTATION DURING THE TERMINAL QUATERNARY SEA-LEVEL CYCLE: LINCOLN SHELF, SOUTHERN AUSTRALIA

1997 ◽  
pp. 53-75 ◽  
Author(s):  
NOEL P. JAMES ◽  
YVONNE BONE ◽  
STEVEN J. HAGEMAN ◽  
DAVID A. FEARY ◽  
VICTOR A. GOSTIN
1999 ◽  
Vol 18 (2) ◽  
pp. 143-168 ◽  
Author(s):  
Stephen J. Gallagher ◽  
Karina Jonasson ◽  
Guy Holdgate

Abstract. This multidisciplinary study integrates fades studies and foraminiferal analyses to assess the palaeoenvironmental evolution of an Oligocene to Miocene cool-water carbonate succession in the Otway Basin, southeastern Australia. The cool-water carbonate succession in the Otway Basin records signals relating to the evolution of the Southern Ocean throughout the Cenozoic. The strata are correlated with the relative coastal onlap curve of Haq et al. (1988) and several sequences can be identified in three formations. The Early Oligocene Narrawaturk Formation (TA 4.5) comprises near the base high-energy, inner shelf biofacies (lowstand systems tracts) and up-section to lower energy mid- to outer shelf marls (TST and maximum flooding surfaces) with storm events and/or minor shallowing intervals. Foraminiferal reworking and post-depositional dolomitization occurs at the top of this unit. The Late Oligocene Clifton Formation (TB 1.1 and TB 1.2.) was deposited in a relatively high-energy inner to mid-shelf environment. The base of this unit preserves evidence of a shift in biofacies that correlates to a major sea-level fall at the Mid/Late Oligocene boundary coincident with a major ice advance in Antarctica, and correlates with other Mid-Oligocene unconformities world-wide. The Late Oligocene Gellibrand Marl Formation (TB 1.2 and TB 1.3) began with low-energy outer shelf cherty marly biofacies (TST and MFS) followed by mid- to outer shelf calcisiltites (HST). High-energy mid- to outer shelf conditions were established after an hiatus in the Late Oligocene. A relative sea-level rise at the base of the Lower Miocene (TB 1.5 and TB2.1) led to the deposition of lower energy outer shelf cherty marls.Four biofacies with distinctive foraminiferal faunas are distinguished. (1) Grey mid- to outer shelf low-energy bryozoal marls with infaunal foraminifera and high plankton values. Two foraminiferal assemblages occur: lagenids and Uvigerina are common in the Narrawaturk marls, whereas bolivinids and Astrononion occur in the Gellibrand marls. The faunal variation in the marls may relate to changes in nutrient supply, anoxia, the presence or absence of organic material and/or changes in depth. (2) Chalky packstone facies with a high epifaunal content were deposited in oligotrophic inner to mid-shelf palaeoenvironments subject to intermittent reworking. (3) Bryozoan-poor inner to outer shelf foraminiferal packstones and grainstones facies enriched in epifaunal forms. (4) Well-sorted coarsegrained regular echinoid and bryozoan-rich packstones to grainstones. Infaunal taxa are absent in this facies, where most preserved foraminifera are robust spherical to discoidal forms. The facies were deposited in inner to mid-shelf palaeoenvironments where reworking by intense wave action (either above normal wavebase or by storms) winnowed out all smaller foraminifera.The stratigraphic and palaeoenvironmental utility of the Cenozoic foraminifera studied is improved greatly by facies analyses. Similar integrated studies will lead to better correlations and palaeoenvironmental interpretations of southeastern Australian sequences and equivalent successions in the southern hemisphere.


Palaios ◽  
2000 ◽  
Vol 15 (1) ◽  
pp. 33-48 ◽  
Author(s):  
S. J. HAGEMAN ◽  
N. P. JAMES ◽  
Y. BONE

2008 ◽  
Vol 78 (12) ◽  
pp. 784-802 ◽  
Author(s):  
J. M. Rivers ◽  
N. P. James ◽  
T. K. Kyser

2010 ◽  
Vol 90 (1) ◽  
pp. 1-16 ◽  
Author(s):  
Ivana Carevic ◽  
Darivojka Ljubovic-Obradovic ◽  
Monika Bozinovic ◽  
Velimir Jovanovic

The Upper Barremian-Lower Aptian succession is recorded from a limestone sequence that crops out in the surrounding of Rakova Bara in the Carpatho-Balkanides range in northeastern Serbia. The micropalaeontological and sedimentological studies lead to recognition of the two types of microfacies. The benthic foraminiferal association consists of Vercorsella laurentii, Rumanoloculina robusta, Praechrysalidina infracretaceae, Dictyoconus gr. arabicus, Debarina hahounerensis, Charentia cuvilieri and Pseudocyclammina lituus that confirm the stratigraphical and palaeoenvironmental connection of the microfossil assemblages with the classical Urgonian-type, shallow-water carbonate sedimentation. The association documented for the first time in the study area is considered typical of the Tethyan Realm. The stratigraphical position of the benthic foraminifera species within the Upper Barremian-Lower Aptian interval is discussed. The Urgonian Limestone's of the studied section are comparable with adjacent areas of eastern Serbia and Romanian South Carpathians. .


1987 ◽  
Vol 35 ◽  
pp. 149-159
Author(s):  
T. N. Koren'

On the basis of biostratigraphic data known at present some preliminary attempts are made to evaluate graptolite dynamics, that is changes in graptolite diversity in time and space within pelagic fades of Si­lurian and Early Devonian age. For the comparative studies of diversity fluctuations versus some major environmental changes a standard graptolite zonation is used. Several critical and more or less well stu­died stratigraphical intervals are chosen; among them the Ordovician/Silurian, Sheinwoodian/Gorstian and Gorstian/Ludfordian boundary beds. For each level the most complete reference sections are analy­zed. Special attention is given to the graptolite extinction, specification and radiation events within these time intervals. They might have been partly connected with or influenced by the environmental factors as a result of eustatic sea-level and climate changes, alteration of anoxic conditions, migration of carbonate sedimentation in pelagic direction, and other globally detectable events. The graptolite evolution during the time of monograptid existence can be subdivided into three phases using the comparison of the ampli­tude of the extinction-origination events and repeatability of the synphasic cycles.


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