New data on Hirnantian (latest Ordovician) postglacial carbonate rocks and fossils in northern Guizhou, Southwest China

The Kuanyinchiao Formation (Hirnantian, Upper Ordovician), yielding the typical Hirnantia fauna, has commonly been accepted as representing cool-water sediments deposited during the glacial interval in the Hirnantian Global Boundary Stratotype Section and Point (GSSP) region of South China. Recent investigation reveals that the uppermost carbonate-dominated part of this formation yields a warm-water rugose coral fauna with Silurian affinities at many localities of northern Guizhou Province, which substantially differs from the underlying cool-water fauna. This suggests that these carbonates were probably postglacial warm-water sediments, rather than having formed during the Hirnantian glacial interval as previously thought. Such a conclusion is consistent with the evidence from the associated brachiopod fauna, i.e., the Dalmanella testudinaria – Dorytreta longicrura community, which is similarly distinct from the underlying typical Hirnantia fauna. The sedimentological data show warm-water features at the same level (e.g., the presence of oolitic grains), also supporting this new interpretation.

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WARM-WATER PLATFORM AND COOL-WATER SHELF CARBONATES OF THE ABROLHOS SHELF, SOUTHWEST AUSTRALIA

Cool-Water Carbonates ◽

10.2110/pec.97.56.0023 ◽

1997 ◽

pp. 23-36 ◽

Cited By ~ 10

Author(s):

LINDSAY B. COLLINS ◽

ROY E. FRANCE ◽

ZHONG RONG ZHU ◽

KARL-HEINZ WYRWOLL

Keyword(s):

Warm Water ◽

Cool Water ◽

Southwest Australia

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Occurrences of the cool-water dalmanelloid brachiopodHeterorthinain the Upper Ordovician of North America

Papers in Palaeontology ◽

10.1002/spp2.1014 ◽

2015 ◽

Vol 1 (3) ◽

pp. 237-253 ◽

Cited By ~ 3

Author(s):

Jisuo Jin ◽

David A. T. Harper

Keyword(s):

North America ◽

Upper Ordovician ◽

Cool Water

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The only known cyclopygid–‘atheloptic’ trilobite fauna from North America: the upper Ordovician fauna of the Pyle Mountain Argillite and its palaeoenvironmental significance

Geological Magazine ◽

10.1017/s0016756812000015 ◽

2012 ◽

Vol 149 (6) ◽

pp. 964-988 ◽

Cited By ~ 2

Author(s):

ALAN W. OWEN ◽

DAVID L. BRUTON

Keyword(s):

New Species ◽

North America ◽

Deep Water ◽

Benthic Fauna ◽

Taxonomic Diversity ◽

Relative Depth ◽

Upper Ordovician ◽

Brachiopod Fauna ◽

Depth Ranges ◽

One New Species

AbstractThe trilobite fauna of the upper Ordovician (middle Katian) Pyle Mountain Argillite comprises a mixture of abundant mesopelagic cyclopygids and other pelagic taxa and a benthic fauna dominated by trilobites lacking eyes. Such faunas were widespread in deep water environments around Gondwana and terranes derived from that continent throughout Ordovician time but this is the only known record of such a fauna from North America and thus from Laurentia. It probably reflects a major sea level rise (the ‘Linearis drowning events’) as does the development of coeval cyclopygid-dominated deep water trilobite faunas in terranes that were marginal to Laurentia and are now preserved in Ireland and Scotland. The Pyle Mountain Argillite trilobite fauna occurs with a deep water Foliomena brachiopod fauna and comprises 22 species. Pelagic trilobites (mostly cyclopygids) constitute 36% of the preserved sclerites, and 45% of the fauna is the remains of trilobites lacking eyes, including one new species, Dindymene whittingtoni sp. nov. Three species of cyclopygid are present, belonging in Cyclopyge, Symphysops and Microparia (Heterocyclopyge). Cyclopygids are widely thought to have been stratified in the water column in life and thus their taxonomic diversity reflects the relative depths of the sea-beds on which their remains accumulated. A tabulation of middle and upper Katian cyclopygid-bearing faunas from several palaeoplates and terranes arranged on the basis of increasing numbers of cyclopygid genera allows an assessment of the relative depth ranges of the associated benthic taxa. The Pyle Mountain Argillite fauna lies towards the deeper end of this depth spectrum.

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Treat burn injuries with cool water initially, then warm water

Nursing Standard ◽

10.7748/ns.27.12.27.s47 ◽

2012 ◽

Vol 27 (12) ◽

pp. 27-27

Author(s):

Helen Evans

Keyword(s):

Burn Injuries ◽

Warm Water ◽

Cool Water

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Marine Mollusca of oxygen isotope stages of the last 2 million years in New Zealand. Part 1: Revised generic positions and recognition of warm‐water and cool‐water migrants

Journal of the Royal Society of New Zealand ◽

10.1080/03014223.2004.9517766 ◽

2004 ◽

Vol 34 (2) ◽

pp. 111-265 ◽

Cited By ~ 50

Author(s):

A. G. Beu ◽

B. V. Alloway ◽

B. J. Pillans ◽

T. R. Naish ◽

J. A. Westgate

Keyword(s):

New Zealand ◽

Oxygen Isotope ◽

Warm Water ◽

Cool Water

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Biostratigraphy and paleobiogeography of Middle and Late Ordovician conodonts from the Langkawi Islands, northwestern peninsular Malaysia

Journal of Paleontology ◽

10.1666/07-058.1 ◽

2008 ◽

Vol 82 (5) ◽

pp. 957-973 ◽

Cited By ~ 19

Author(s):

Sachiko Agematsu ◽

Katsuo Sashida ◽

Amnan B. Ibrahim

Keyword(s):

North Atlantic ◽

Peninsular Malaysia ◽

Late Ordovician ◽

Upper Ordovician ◽

Low Latitude ◽

Cool Water ◽

Middle Ordovician ◽

Water Conditions ◽

Unidentified Species ◽

Assemblage Zone

The Middle and Upper Ordovician sequence of the Langkawi Islands, northwestern peninsular Malaysia, contains 20 species of conodonts belonging to 15 genera and four unidentified species, which are described and illustrated. The following four biostratigraphic zones are established for the study area: the Scolopodus striatus assemblage zone, the Periodon sp. A range zone, the Baltoniodus alobatus range zone, and the Hamarodus europaeus range zone, in ascending order. The Middle Ordovician fauna belongs to the low-latitude, warm-water Australian Province. Conodonts of the H. europaeus zone represent the HDS (Hamarodus europaeus-Dapsilodus mutatus-Scabbardella altipes) biofacies, which has been reported from the cool-water North Atlantic Faunal Region. The middle Arenigian limestones in the study area were deposited on a shallow-water shelf, whereas the late Arenigian to middle Darriwilian limestones formed in hemipelagic deeper-water conditions on an outer shelf or slope.

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Foraminiferal biostratigraphy of the Visean–Serpukhovian (Mississippian) boundary interval at slope and platform sections in southern Guizhou (South China)

Journal of Paleontology ◽

10.1666/11-111.1 ◽

2012 ◽

Vol 86 (5) ◽

pp. 753-774 ◽

Cited By ~ 26

Author(s):

John R. Groves ◽

Wang Yue ◽

Qi Yuping ◽

Barry C. Richards ◽

Katsumi Ueno ◽

...

Keyword(s):

Guizhou Province ◽

Reference Area ◽

Type Area ◽

Slope Deposits ◽

Central United States ◽

Moscow Basin ◽

Stratotype Section ◽

Foraminiferal Biostratigraphy ◽

Serpukhovian Stage

The Visean–Serpukhovian boundary is not yet defined by a Global Stratotype Section and Point (GSSP) but it is recognizable operationally by the appearance of the conodont Lochriea ziegleri in the L. nodosa–L. ziegleri chronocline. Foraminiferal successions across this boundary in the type area of the Serpukhovian Stage (Moscow Basin, Russia), elsewhere in Russia and in the central United States suggest that the appearances of Asteroarchaediscus postrugosus, Janischewskina delicata, Eolasiodiscus donbassicus, and specimens controversially referred to “Millerella tortula” are reliable, auxiliary indices to the base of the Serpukhovian. In southern Guizhou Province, China, Visean–Serpukhovian rock sequences from slope and platform settings have yielded rich associations of conodonts and foraminifers, respectively. The Nashui section is a leading candidate for the Serpukhovian GSSP because its slope deposits contain an uninterrupted record of conodont occurrences including the L. nodosa–L. ziegleri transition. Foraminifers recovered from the Nashui section are comparatively rare and include none of the basal Serpukhovian indices. In contrast, the nearby Yashui section represents a platform interior setting in which foraminifers flourished and conodonts were nearly absent. The base of the Serpukhovian at Yashui is marked approximately by the appearance of “tortula-like” specimens. Although it is not possible to correlate biostratigraphically between the Nashui and Yashui sections, the occurrence of “tortula-like” specimens at the Yashui section allows correlation with the mid-Venevian Substage of the Moscow Basin at a level coinciding with the appearance of L. ziegleri. Together, the slope and platform sections comprise an informative biostratigraphic reference area for micropaleontologic characterization of the Visean–Serpukhovian boundary in southern Guizhou.

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Chronometric calibration of mid-Ordovician to Tournaisian conodont zones: a compilation from recent graphic-correlation and isotope studies

Geological Magazine ◽

10.1017/s001675680000844x ◽

1992 ◽

Vol 129 (6) ◽

pp. 709-721 ◽

Cited By ~ 39

Author(s):

Barry G. Fordham

Keyword(s):

High Resolution ◽

High Precision ◽

Time Scale ◽

Lower Devonian ◽

New South ◽

Upper Ordovician ◽

South Wales ◽

Isotope Studies ◽

Stratotype Section ◽

Upper Silurian

AbstractThree available graphic-correlation analyses are used to calibrate mid-Palaeozoic conodont zonations: Sweet's scheme for the mid- to Upper Ordovician; Kleffner's for the mid- to Upper Silurian; and Murphy & Berry's for the lower and middle Lower Devonian. The scheme of Sweet is scaled by applying the high-precision U-Pb zircon date of Tucker and others for the Rocklandian and linked with that of Kleffner by scaling the graptolite sequence of the Ordovician-Silurian global stratotype section to fit two similarly derived dates from this sequence. The top of Kleffner's scheme, all of Murphy & Berry's, as well as standard zones to the Frasnian are calibrated by using tie-points of the latest Cambridge-BP time-scale (GTS 89). However, the recent microbeam zircon date by Claoué-Long and others for the Hasselbachtal Devonian-Carboniferous auxiliary stratotype is used to calibrate the standard Famennian zones. Also the similarly derived but preliminary determination reported by Roberts and others from the Isismurra Formation of New South Wales is tentatively taken as the top of the Tournaisian and so used to calibrate Tournaisian zones. Despite the considerable extrapolation required to compile these schemes and their inherent errors, the resultant time-scale closely agrees with other dates of Tucker and others from the Llanvirn as well as the GTS 89 Homerian-Gorstian tie-point. This suggests that stratigraphic methods can be usefully applied to geochronometry. The Llandovery appears to have lasted longer (16 m. y.) than usually envisaged and the Ordovician-Silurian boundary may need to be lowered to approximately 443.5 Ma. Certainly, chrons varied widely in duration and further stratigraphic studies to estimate their relative durations as well as high-resolution dating for their calibration will be crucial to more accurate biochronometries.

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Middle Permian (Guadalupian) fusulinid taxonomy and biostratigraphy of the mid-latitude Dalan Basin, Zagros, Iran and their applications in paleoclimate dynamics and paleogeography

GeoArabia ◽

10.2113/geoarabia180217 ◽

2013 ◽

Vol 18 (2) ◽

pp. 17-62 ◽

Cited By ~ 1

Author(s):

Vladimir I. Davydov ◽

Arefifard Sakineh

Keyword(s):

Water Temperature ◽

Passive Margin ◽

Warm Water ◽

Middle Permian ◽

Arabian Plate ◽

Upper Permian ◽

Modern World ◽

Temporal And Spatial Distribution ◽

Climatic Fluctuations ◽

Cool Water

ABSTRACT The Middle–Upper Permian (Guadalupian–Lopingian) Dalan Basin was part of a very large carbonate ramp/platform along the passive margin of the Arabian Plate, located at mid-latitude Neo-Tethys Ocean. As shown in the modern world the mid-latitudes are areas where climatic fluctuations and velocity of climate change are most significant. Consequently, the most significant variations in foraminiferal diversity occur at higher latitudes as already noted for the Middle Permian (Guadalupian) foraminifers’ record. The fusulinids as a large, warm-water foraminifera were quite sensitive to water temperature. The optimal water temperature for recent warm-water benthic foraminifera with living symbionts, and consequently for fusulinids, is 20–30°C, while the lower limit is 14–16°C. Three climatically-determined assemblages were distinguished in Zagros and the surrounding areas. The first assemblage is characteristic of temperate, cool-water environments and contains smaller foraminifera with no symbionts, which possess resistance to such environments. Fusulinid staffellids, schubertellids, Chusenella, Eopolydiexodina and Monodiexodina can be found in the warmer water environments in a second climatic assemblage, transitional from temperate- to warm-water state. The third assemblage is characterized by the presence of verbeekinids in warm-water conditions in Zagros and appeared where surface-water temperature exceeded approximately 25°C. The proposed model of climate fluctuations and paleogeography in the Neo-Tethys is based on analyses of temporal and spatial distribution of fusulinids. Also, a temperate cool-water Monodiexodina is recorded in this area for the first time. Three new species of fusulinids are described.

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