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Shinichi Sano - One of the best experts on this subject based on the ideXlab platform.
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paleobiogeography of the pectinid bivalve neithea and its pattern of step wise demise in the Albian northwest pacific
2008Co-Authors: Yasuhiro Iba, Shinichi SanoAbstract:article i nfo The pectinid bivalve genus Neithea is one of the most important indicators for understanding the biogeographic relationships between the Tethyan Realm and North Pacifi cP rovince during the Cretaceous Period. Changes in temporal species diversity, endemic/widespread species composition, and origination and demise ratios of Neithea ateach Cretaceous stage boundary in the Northwest Pacific were analyzed from a biogeographic perspective. Neithea is continuously present in the Northwest Pacific during the Berriasian to late Albian time interval. Species diversity reached its maximum in the late Aptian, being correlated with the global warming phase. Step-wise demise of Neithea in the Northwest Pacific during the Albian is subdivided into three stages: the late Aptian/early Albian, early Albian/middle-late Albian, and late Albian/ early Cenomanian. Thereafter, Neithea disappeared in the Northwest Pacific and never reappeared. This pattern is the reverse of the Albian diversification of Neithea in the Mediterranean, and also contrary to the Mid-Cretaceous global warming trend. Demise of Neithea in the Northwest Pacific occurred simultaneously with the step-wise demise of Mesogean taxa (e.g., rudists) which strongly supports the idea that the Northwest Pacific gradually became independent from the Tethyan Realm during the Albian. It also suggests a long-term deterioration of the faunal interchange between the North Pacific Province and Tethyan Realm throughout the Late Cretaceous. This biogeographic change was possibly caused by Albian "cooling" and changes in oceanic flow/heat transport in the Northwest Pacific.
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mid cretaceous step wise demise of the carbonate platform biota in the northwest pacific and establishment of the north pacific biotic province
2007Co-Authors: Yasuhiro Iba, Shinichi SanoAbstract:Abstract The global spatiotemporal distribution of the Cretaceous carbonate platform biota, which is characterized by “tropical” Mesogean (= Cretaceous Tethys) taxa, is an important aspect of Earth's paleobiogeography. All available records of this biota in the Northwest Pacific (Japan and Sakhalin Island) are summarized in order to elucidate its stratigraphic distribution patterns and faunal changes, with special attention given to the biota of the Late Aptian–Early Albian. This carbonate platform biota flourished from the Berriasian to Early Albian interval in the Northwest Pacific, indicating that the Northwest Pacific clearly belonged to the Tethyan biotic realm at that time. A step-wise demise of the carbonate platform biota transpired in the latest Aptian to middle Albian interval. Mesogean key taxa (rudists and dasycladacean algae), some Mesogean indicators (hermatypic corals and stromatoporoids) and nerineacean gastropods disappeared at the Late Aptian to Early Albian transition. Following this event, other Mesogean indicators (orbitolinid foraminifers and calcareous red algae) and coated grains disappeared at the Early to middle Albian transition. There is no record of carbonate platform biota in the Northwest Pacific during the long interval between the Middle Albian and Paleocene. The step-wise demise of the carbonate platform biota in the latest Aptian–middle Albian interval strongly implies a “vicariance event”, which separated the North Pacific from the Tethyan biotic realm and established the North Pacific biotic province.
Jens O Herrle - One of the best experts on this subject based on the ideXlab platform.
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Albian to santonian carbon isotope excursions and faunal extinctions in the canadian western interior sea recognition of eustatic sea level controls on a forebulge setting
2012Co-Authors: Claudia J Schroderadams, Jens O HerrleAbstract:Abstract The forebulge region of the Cretaceous Canadian Western Interior Sea (CWIS) was susceptible to subaerial exposure and marine erosion during sea level lowstands. The middle Albian to Santonian record as cored at Cold Lake, east-central Alberta, Canada documents numerous disconformities that are expressed in bioclastic concentration horizons and faunal extinctions and turnovers. Detailed comparison between a newly established δ 13 C org. record measured on bulk sediment at Cold Lake and a combined δ 13 C carb. reference curve based on the Cretaceous English chalk and SE France hemipelagic marlstones highlights missing positive and negative δ 13 C excursions at the CWIS forebulge and thus missing sections that precisely corroborate with sequence boundaries. Disconformable boundaries correlate closely with global sea-level lowstands as established for the Cretaceous North Atlantic suggesting a pronounced eustatic influence on the CWIS forebulge setting. Sequence boundaries occur in the uppermost Middle Albian, lowermost Upper Albian, Albian/Cenomanian boundary, Cenomanian/Turonian boundary, middle Turonian to lower Coniacian and uppermost Middle Santonian, each followed by a positive δ 13 C excursion. Oceanic anoxic events 1d, 2 and 3 are recognized and linked to major faunal and floral assemblage changes. Of these the Albian/Cenomanian biotic turnover is the most severe in the CWIS marked by the total loss of Albian benthic foraminifera species. Causes of this benthic extinction might be linked to a period of anoxia (OAE 1d) during the latest Albian followed by sea-level controlled basin restriction.
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high resolution carbon isotope records of the aptian to lower Albian from se france and the mazagan plateau dsdp site 545 a stratigraphic tool for paleoceanographic and paleobiologic reconstruction
2004Co-Authors: Jens O Herrle, Peter Kosler, Oliver Friedrich, Helmut Erlenkeuser, Christoph HemlebenAbstract:High-resolution carbon isotope stratigraphy is established for the Aptian to Lower Albian of the Vocontian Basin (SE France), and correlated to the carbon isotope record of the Mazagan Plateau (DSDP Site 545). The carbon isotope stratigraphy of the Vocontian Basin is proposed as a standard reference curve for the Aptian to Lower Albian, due to the completeness and high temporal resolution of the stratigraphic succession, the good biostratigraphical time control, and the frequent occurrence of regional to global black shale horizons including Oceanic Anoxic Events 1a (OAE 1a) of the Lower Aptian and OAE 1b of the Lower Albian. The carbon isotope record appears better suited for long-distance short-term correlation of different marine and terrestrial environments than biostratigraphy because of the synchroneity of carbon isotope signals in a range of sediment types. However, the combination of both biostratigraphy and carbon isotope stratigraphy provides an effective tool to reconstruct biotic change and paleoceanography, and to correlate regional to global black shale horizons in different marine environments. This combined approach allows us to ascertain the synchroneities or diachroneities of first and last appearances of biostratigraphic marker species. Based on the demonstrated diachroneity of important biostratigraphic markers of the Aptian/Albian boundary, the globally observed break point between the end of the uppermost Aptian positive carbon isotope excursion and the onset of the pronounced negative shift of δ13C values, is an alternative criterion. The distinctive structure and amplitudes of the carbon isotope record are observed in both the inorganic and organic carbon and can therefore be recognized in all marine and terrestrial environments of the Aptian to Lower Albian.
Takuto Ando - One of the best experts on this subject based on the ideXlab platform.
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Establishment of Upper Cretaceous bio- and carbon isotope stratigraphy in the northwest Pacific Ocean and radiometric ages around the Albian/Cenomanian, Coniacian/Santonian and Santonian/Campanian boundaries
2019Co-Authors: Reishi Takashima, Hiroshi Nishi, Toshiro Yamanaka, Yuji Orihashi, Yasuyuki Tsujino, Xavier Quidelleur, Keiichi Hayashi, Ken Sawada, Hideto Nakamura, Takuto AndoAbstract:The Yezo Group, exposed in Hokkaido, northern Japan, is one of the few strata that recorded Cretaceous paleo-oceanographic changes in the Pacific Ocean. Although the group yields abundant marine macro- and microfossils, sporadic occurrences of age-diagnostic species in several stratigraphic intervals has prevented high-resolution international biostratigraphic correlation. The proposed integrated bio- and carbon isotope stratigraphy of the Yezo Group, which is exposed in northwest Hokkaido, enables high-resolution international stratigraphic correlation spanning from Upper Albian to Lower Campanian. The correlation of the present study identifies the detailed stratigraphic horizons of the Albian/Cenomanian, Cenomanian/Turonian, Turonian/Coniacian, Coniacian/Santonian, and Santonian/Campanian boundaries, as well as the Late Cretaceous paleo-environmental events in the Yezo Group. The Yezo Group is also important in order to complement the chronometric age of the Cretaceous geologic time scale because the group includes numerous felsic tuffs. The U-Pb zircon ages of some of these tuffs, which are interbedded near the Albian/Cenomanian, Coniacian/Santonian and the Santonian/Campanian boundaries in the Yezo Group, are dated at 99.7±0.3 Ma (Quidelleur et al. 2011), 86.87±0.60/0.67 (internal/total error) Ma and 84.7±0.7/1.8 (internal/total error) Ma, respectively. These radiometric ages are consistent with the latest age model of the Cretaceous time scale.
Yasuhiro Iba - One of the best experts on this subject based on the ideXlab platform.
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paleobiogeography of the pectinid bivalve neithea and its pattern of step wise demise in the Albian northwest pacific
2008Co-Authors: Yasuhiro Iba, Shinichi SanoAbstract:article i nfo The pectinid bivalve genus Neithea is one of the most important indicators for understanding the biogeographic relationships between the Tethyan Realm and North Pacifi cP rovince during the Cretaceous Period. Changes in temporal species diversity, endemic/widespread species composition, and origination and demise ratios of Neithea ateach Cretaceous stage boundary in the Northwest Pacific were analyzed from a biogeographic perspective. Neithea is continuously present in the Northwest Pacific during the Berriasian to late Albian time interval. Species diversity reached its maximum in the late Aptian, being correlated with the global warming phase. Step-wise demise of Neithea in the Northwest Pacific during the Albian is subdivided into three stages: the late Aptian/early Albian, early Albian/middle-late Albian, and late Albian/ early Cenomanian. Thereafter, Neithea disappeared in the Northwest Pacific and never reappeared. This pattern is the reverse of the Albian diversification of Neithea in the Mediterranean, and also contrary to the Mid-Cretaceous global warming trend. Demise of Neithea in the Northwest Pacific occurred simultaneously with the step-wise demise of Mesogean taxa (e.g., rudists) which strongly supports the idea that the Northwest Pacific gradually became independent from the Tethyan Realm during the Albian. It also suggests a long-term deterioration of the faunal interchange between the North Pacific Province and Tethyan Realm throughout the Late Cretaceous. This biogeographic change was possibly caused by Albian "cooling" and changes in oceanic flow/heat transport in the Northwest Pacific.
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mid cretaceous step wise demise of the carbonate platform biota in the northwest pacific and establishment of the north pacific biotic province
2007Co-Authors: Yasuhiro Iba, Shinichi SanoAbstract:Abstract The global spatiotemporal distribution of the Cretaceous carbonate platform biota, which is characterized by “tropical” Mesogean (= Cretaceous Tethys) taxa, is an important aspect of Earth's paleobiogeography. All available records of this biota in the Northwest Pacific (Japan and Sakhalin Island) are summarized in order to elucidate its stratigraphic distribution patterns and faunal changes, with special attention given to the biota of the Late Aptian–Early Albian. This carbonate platform biota flourished from the Berriasian to Early Albian interval in the Northwest Pacific, indicating that the Northwest Pacific clearly belonged to the Tethyan biotic realm at that time. A step-wise demise of the carbonate platform biota transpired in the latest Aptian to middle Albian interval. Mesogean key taxa (rudists and dasycladacean algae), some Mesogean indicators (hermatypic corals and stromatoporoids) and nerineacean gastropods disappeared at the Late Aptian to Early Albian transition. Following this event, other Mesogean indicators (orbitolinid foraminifers and calcareous red algae) and coated grains disappeared at the Early to middle Albian transition. There is no record of carbonate platform biota in the Northwest Pacific during the long interval between the Middle Albian and Paleocene. The step-wise demise of the carbonate platform biota in the latest Aptian–middle Albian interval strongly implies a “vicariance event”, which separated the North Pacific from the Tethyan biotic realm and established the North Pacific biotic province.
Paul R. Bown - One of the best experts on this subject based on the ideXlab platform.
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cretaceous Albian turonian calcareous nannofossil biostratigraphy of the onshore cauvery basin southeastern india
2021Co-Authors: Sudeep Kanungo, Paul R. Bown, Andrew S. GaleAbstract:Abstract A suite of outcrop samples from the Cauvery Basin belonging to the mudrock-claystone dominated Karai Formation were analysed for nannofossil biostratigraphy in two newly measured sections at Karai and Garudamangalam. The age of the Karai Section is interpreted as early Albian to early Turonian, whereas the Garudamangalam Section is interpreted as late Albian to late Cenomanian. The Albian ‘BC’ zones of Bown et al. (1998) are applicable in both sections, whereas the Cenomanian and Turonian ‘UC’ zones of Burnett (1998), are only partially applicable, due to some problematic primary and secondary markers. The Albian-Cenomanian boundary appears to be continuous and is approximated in both sections using the FO of lower Cenomanian ammonites of the M. mantelli Zone. The Cenomanian-Turonian boundary interval is incomplete in the two sections, with a hiatus of ~0.66 myr, indicated by the absence of the upper Cenomanian Nannofossil Zone UC5. The nannoplankton assemblages are composed of broadly cosmopolitan taxa, despite the relatively high-latitude setting of SE India during the Albian (~45°S), which is reflected in the common occurrence of biogeographically bipolar taxa such as Repagulum parvidentatum and Seribiscutum primitivum. The palaeobiogeographic affinity of the nannoplankton, however, does not bear a distinct Austral stamp, as typical Austral taxa, such as Sollasites falklandensis and Zeugrhabdotus kerguelenensis are very rare in the studied sections. The early appearance of Crucibiscutum hayi in the lower Albian, and Gartnerago segmentatum in the upper Albian in the Cauvery Basin suggests that these two species may have originated in southern high latitudes before migrating to the northern Boreal regions. Four new calcareous nannofossil species, Calculites karaiensis, Loxolithus bicyclus, Manivitella fibrosa and Tranolithus simplex are described.
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the uppermost middle and upper Albian succession at the col de palluel hautes alpes france an integrated study ammonites inoceramid bivalves planktonic foraminifera nannofossils geochemistry stable oxygen and carbon isotopes cyclostratigraphy
2011Co-Authors: Andrew S. Gale, Paul R. Bown, Michele Caron, James S Crampton, S J Crowhurst, W J Kennedy, Maria Rose Petrizzo, David WrayAbstract:An integrated study of the ammonites, inoceramid bivalves, planktonic foraminifera, calcareous nannofossils, geochemistry, stable carbon isotopes, and cyclostratigraphy is provided for the upper Middle to upper Upper Albian sucession exposed in the Col de Palluel section east of Rosans in Hautes-Alpes, France. The Albian-Cenomanian boundary interval described by Gale et al. at Mont Risou is re-examined, a total thickness of 370 m of the Marnes Bleues Formation. Zonal schemes based on ammonites, inoceramid bivalves, planktonic foraminifera, and calcareous nannofossils are integrated with the stable carbon isotope curve and key lithostratigraphic markers to provide a sequence of more than 70 events in the uppermost Middle Albian to basal Cenomanian interval. Time series analysis of the Al2O3 content of the 500 m Albian sequence present in the Col de Palluel and Risou sections reveals the presence of the 20 kyr precession, 40 kyr tilt, 100 kyr short eccentricity, and 406 kyr long eccentricity cycles. Correlation using planktonic foraminiferan and nannofossil data provide a link between the Col de Palluel and Risou sections and the Italian sequence at Gubbio, and in the Piobbico core. This provides a basis for the extension of the orbital time scale of Grippo et al. to the sequence. It reveals a major break in the Col de Palluel succession at the top of the distinctive marker bed known as the Petite Verde that may represent as much as 2 Ma. It also provides a basis for the estimation of the length of the Albian Stage at 4.12 Ma, 0.8 Ma for the early Albian, 2.84 Ma for the Middle Albian, and 3.68 Ma for the late Albian substages. (C) 2010 Elsevier Ltd. All rights reserved.
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fluctuations in biosiliceous production and the generation of early cretaceous oceanic anoxic events in the pacific ocean shatsky rise ocean drilling program leg 198
2004Co-Authors: Stuart A Robinson, Trevor Williams, Paul R. BownAbstract:Integration of geophysical logs with sedimentological, biostratigraphic, and physical properties data from poorly recovered chert-rich sequences at Ocean Drilling Program Leg 198 Sites 1207 and 1213 allows us to propose an Aptian–Albian (Early Cretaceous) depositional history for Shatsky Rise (North Pacific Ocean). The logs indicate that the lower Aptian and lower Albian deposits are relatively lithified and unporous compared to contiguous sediments. These characteristics are best explained by increased siliceous cementation that resulted from an elevated flux of radiolarians to the seafloor. The intervals of increased biosiliceous production may record a biotic response to enhanced nutrient delivery, coeval with (but longer in duration than) oceanic anoxic events (OAEs) 1a (early Aptian) and 1b (early Albian). On Shatsky Rise, OAE 1a is represented by organic-carbon-rich sediments, but OAE 1b is not. Thus “black shale” deposition in the Pacific Ocean was only possible when a “carbon-burial threshold” was crossed. We speculate that this threshold was related to the balance between productivity and carbon oxidation and that, ultimately, the supply of biolimiting nutrients through hydrothermal alteration of basalt may have been the key to the development of “black shale” in the Pacific basin.
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integrated stratigraphy across the aptian Albian boundary in the marnes bleues at the col de pre guittard arnayon drome and at tartonne alpes de haute provence france a candidate global boundary stratotype section and boundary point for the base of the Albian stage
2000Co-Authors: W J Kennedy, Andrew S. Gale, Paul R. Bown, Michele Caron, R J Davey, Darren R Grocke, David WrayAbstract:The history of definition of the Aptian-Albian boundary is reviewed with particular reference to the ammonite schemes of Brinkmann (1937), Breistroffer (1947), Casey (1961a, 1996, 1999), Kemper (1982), Owen (1996, 1999), and Ruffell & Owen (1995). The classic sequence in the Hannover area of Germany described by Brinkmann (1937) is reviewed in the light of subsequent work. The definition of the base of the Albian Stage at the first occurrence of the ammonite Proleymeriella schrammeni (Jacob, 1907) is rejected as it can only be recognised over a limited area near Hannover; no more widely recognised secondary markers have been documented, and there is no permanent section at the present rime. An alternative Aptian-Albian boundary, defined by the first occurrence of the ammonite Leymeriella (L.) tardefurcata (d'Orbigny, 1841) in the expanded Marnes Bleues section at Tartonne, Alpes-de-Haute-Provence, France, is suggested. The palynomorph, coccolith, planktonic foraminiferan, ammonite, and inoceramid bivalve sequence, organic and inorganic carbon, trace, rare earth, and major element record, oxygen and carbon isotope sequence, and strontium isotope data are presented for sections at the Col de Pre-Guittard, Arnayon (Drome), and Tartonne (Alpes-de-Haute-Provence) and described in detail. The Pre-Guittard section, considered as a candidate Global Boundary Stratotype Section (GSS) for the base of the Albian Stage at the Second International Symposium on Cretaceous Stage Boundaries held in Brussels in September 1995, provides a standard section for the boundary interval in SE France. It is, however, unsuitable as a GSS, as there is a hiatus at the critical level in the section. In contrast, the Tartonne section is a potential GSS. The Boundary Point for the base of the Albian Stage suggested here is the first criterion proposed at Brussels: the first appearance of the ammonite Leymeriella (L.) tardefurcata at the base of the Niveau Paquier within the expanded Marnes Bleues sequence. The first appearance is only 60 cm above the last record of its presumed ancestor, L. (L.) germanica Casey, 1957. So defined, the boundary lies within the Prediscosphaera columnata Nannofossil (NF) Zone NC/CC8, and the planktonic foraminiferal Hedbergella planispira Partial Range Zone. There is no major or trace element event associated with the proposed boundary, nor is there any distinctive oxygen or carbon isotopic signal. Strontium isotope data from the Tartonne section are compatible with those elsewhere in the basin, and show that the base of the Albian, defined by the first appearance of L. (L.) taudefurcata corresponds to an Sr-87/Sr-86 ratio of 0.707339 +/- 2. Systematic sections deal with a new palynomorph, calcareous nannofossils and ammonites; full range data and taxonomic indices are given for the first two groups.