Artículos de revistas: "Pliocene-Pleistocene boundary"

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Pedersen, Anette Mønsted. "Pliocene - Middle Pleistocene biostratigraphy in the Central Danish North Sea wells E-1, P-1 and TWB-12". Danmarks Geologiske Undersøgelse Serie C 13 (31 de diciembre de 1995): 1–28. http://dx.doi.org/10.34194/seriec.v13.7117.

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Six foraminiferal assemblage zones and 6 subzones have been identified in the boreholes TWB-12, P-1 and E-1. The zones cover the interval from the Pliocene to the Middle Pleistocene. In TWB-12 and E-1 the Pliocene /Pleistocene boundary is placed at the first common occurrence of the species Elphidium oregonense. This species was not found in P-1, and the boundary is here, tentatively, placed above the last local occurrence of Cibicides grossus. The palaeoecological variations indicated by the Pleistocene assemblages, suggest several oscillations both in water depth and in palaeotemperature. A cold, shallow water interval with Elphidium oregonense at the Pliocene/Pleistocene boundary is followed by a Early Pleistocene warm, deep water interval with a high content of the genera Stainforthia and Bulimina. These deposits are probably from the warm Tiglian stage. The succeeding Early Pleistocene fauna! assemblages indicate a cold, upwards shallowing environment, and in this interval the arctic species Elphidiella gorbunovi often has a short ranged occurrence. The fauna! assemblages of the overlying deposits are characterized by the species Elphidium ustulatum and Elphidium albiumbilicatum, and indicates nearshore/ deltaic conditions. This part of the sequence probably includes the Early /Middle Pleistocene boundary. The uppermost assemblages in the examined sequence indicate arctic, shallow water conditions. They are, probably, of Saalian age, and are referred to Middle Pleistocene.

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Cosentino, Domenico, Paola Cipollari, Letizia Di Bella, Alessandra Esposito, Costanza Faranda, Guido Giordano, Elsa Gliozzi et al. "Tectonics, sea-level changes and palaeoenvironments in the early Pleistocene of Rome (Italy)". Quaternary Research 72, n.º 1 (julio de 2009): 143–55. http://dx.doi.org/10.1016/j.yqres.2009.03.003.

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AbstractThe historical site of the Monte Mario lower Pleistocene succession (Rome, Italy) is an important marker of the Pliocene/Pleistocene boundary. Recently, the Monte Mario site was excavated and restudied. A spectacular angular unconformity characterizes the contact between the Monte Vaticano and the Monte Mario formations, which marks the Pliocene/Pleistocene boundary. Biostratigraphical analyses carried out on ostracod, foraminifer, and calcareous nannofossil assemblages indicate an Early Pliocene age (topmost Zanclean, 3.81–3.70 Ma) for the underlying Monte Vaticano Formation, whereas the Monte Mario Formation has been dated as early Pleistocene (Santernian, 1.66–1.59 Ma). Palaeomagnetic analyses point to C2Ar and C1r2r polarity chrons for the Monte Vaticano and the Monte Mario formations, respectively. The Monte Mario Formation consists of two obliquity-forced depositional sequences (MM1 and MM2) characterized by transgressive systems tracts of littoral marine environments at depths, respectively, of 40–80 m and 15–20 m. The data obtained from foraminifer and ostracod assemblages allow us to reconstruct early Pleistocene relative sea-level changes near Rome. At the Plio/Pleistocene transition, a relative sea-level drop of at least 260 m occurred, as a result of both tectonic uplift of the central Tyrrhenian margin and glacio-eustatic changes linked to early Pleistocene glaciation (Marine Isotope Stage 58).

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3

Mai, Dieter Hans y Evagelos Velitzelos. "The fossil flora of Kallithea (Rhodes, Greece) at the Pliocene/Pleistocene boundary". Palaeontographica Abteilung B 277, n.º 1-4 (17 de diciembre de 2007): 75–99. http://dx.doi.org/10.1127/palb/277/2007/75.

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4

Маtveyev, A. V., Т. B. Rylova, S. V. Demidova y Т. V. Yakubovskaya. "Changes in stratigraphic charts of neogene and quaternary deposits of Belarus due to the revision of the boundary between systems". Doklady of the National Academy of Sciences of Belarus 63, n.º 3 (28 de junio de 2019): 350–59. http://dx.doi.org/10.29235/1561-8323-2019-63-3-350-359.

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Following the decision of the International Union of Geological Sciences on the transfer of the lower boundary of the Quaternary System/Period and the Pleistocene Series/Epoch from 1.8 Ma to 2.58 Ma (to the base of the Gelazian Stage/ Age of the Pliocene), the changes have been made in Stratigraphic charts of Neogene and Quaternary Deposits of Belarus (2010). The Neogene – Quaternary boundary in the territory of Belarus is aligned with the International Chronostratigraphic Chart and is made between the Kholmech horizon (analogue of Zanclean and Piacenzian, Pliocene) and the Dvorets horizon (analogue of Gelasian) displaced from the Pliocene to the lower base of the lowermost Pleistocene. Its new position in the sections is substantiated by paleobotanical data. New geological units were introduced into regional and local stratigraphic charts of the Neogene and Quaternary.

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5

Urban, Brigitte. "Stratigraphische Begriffe für das Quartär des Periglazialraums in Deutschland". E&G Quaternary Science Journal 56, n.º 1/2 (1 de marzo de 2007): 84–95. http://dx.doi.org/10.3285/eg.56.1-2.04.

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Abstract. Only a few Quaternary deposits of the periglacial area in Germany can be described in paleoecological or palynological - and therefore climatostratigraphical - terms. This paper provides a supplementary description of the most important (bio)stratigraphical terms relating to the warm and cold stages of the Lower and Middle Pleistocene, especially those allowing correlations with the glaciated regions of northern and southern Germany (e.g. in STEPHAN & MENKE 1993; Litt et al., this volume). The chronostratigraphical subdivision into Lower, Middle and Upper Pleistocene is based on the Stratigraphical Table of Germany 2002 (STD 2002) and on the climatostratigraphical regional division into cold and warm stages for continental northwestern Europe and Germany (LITT et al. 2005), which follows the traditional positioning of the Pliocene/Pleistocene boundary at the transition between the Reuverian and Pretiglian stages (Zagwijn 1960). According to international agreement on the location of the GSSP at Vrica (Italy), the sections of the Pretiglian stage and the Tiglian Complex belong to the Gelasian, which is still assigned to the Pliocene. The Gelasian/Calabrian boundary was set at about 1.8 million years at the Vrica section at the top of the Olduvai magnetozone and therefore represents the internationally agreed base of the Pleistocene. The practical value of this boundary – which does not take prior major climatic events into account – has been a matter of controversy. By international consensus, the boundary between the Lower and Middle Pleistocene has been set at the palaeomagnetically defined Brunhes/Matuyama boundary at 780 ka; the Upper Pleistocene begins with the last interglacial, the Eemian stage (MIS 5e).

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ZACWIJN, WALDO H. "The Pliocene-Pleistocene boundary in western and southern Europe". Boreas 3, n.º 3 (16 de enero de 2008): 75–97. http://dx.doi.org/10.1111/j.1502-3885.1974.tb00666.x.

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7

Shackleton, N. J. "The deep-sea sediment record and the Pliocene-Pleistocene boundary". Quaternary International 40 (enero de 1997): 33–35. http://dx.doi.org/10.1016/s1040-6182(96)00058-4.

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8

Satoguchi, Yasufumi. "Widespread tephras aronnd the Pliocene-Pleistocene boundary and age resolution of tephrostratigraphy in the Pleistocene". Quaternary Research (Daiyonki-Kenkyu) 49, n.º 5 (2010): 315–22. http://dx.doi.org/10.4116/jaqua.49.315.

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9

Takayama, Toshiaki, Tokiyuki Sato, Koji Kameo y Tomiko Goto. "Quaternary Coccolith Biostratigraphy and the Age of the Pliocene/Pleistocene Boundary." Quaternary Research (Daiyonki-Kenkyu) 34, n.º 3 (1995): 157–70. http://dx.doi.org/10.4116/jaqua.34.157.

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10

Gladenkov, Andrey Yu. "Diatom Assemblages from the Pliocene-Pleistocene Boundary Beds in Kamchatka, Russia". Micropaleontology 40, n.º 1 (1994): 79. http://dx.doi.org/10.2307/1485801.

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11

Jenkins, D. G. "Was the Pliocene-Pleistocene boundary placed at the wrong stratigraphic level?" Quaternary Science Reviews 6, n.º 1 (enero de 1987): 41–42. http://dx.doi.org/10.1016/0277-3791(87)90015-1.

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12

Krzyszkowski, D. y A. Szuchnik. "Pliocene—pleistocene boundary in the Kleszczów Graben at Belchatów, central Poland". Journal of Quaternary Science 10, n.º 1 (marzo de 1995): 45–58. http://dx.doi.org/10.1002/jqs.3390100106.

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13

Menke, Burchard. "Results of pollen analysis on the Pleistocene stratigraphy and the Pliocene-Pleistocene boundary in Schleswig-Holstein". DEUQUA Special Publications 3 (17 de diciembre de 2021): 87–99. http://dx.doi.org/10.5194/deuquasp-3-87-2021.

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14

Spies, A. "A search for evidence of a distant human past outside Africa". Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie 6, n.º 1 (17 de marzo de 1987): 4–11. http://dx.doi.org/10.4102/satnt.v6i1.935.

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Dating the Pleistocene and also the Ice Ages is necessary. A period of “normal” magnetism, called the Olduvai Event, occurred about 1,8 m.y.a. It can be considered the boundary between the Pliocene and the Pleistocene, lying within the Matuyama Reversed Epoch, which ended some 700 000 y.a. The boundary between the Middle and Upper or late Pleistocene we shall accept as 125 000 y.a., which is also the beginning of the Eemian interglacial. Hominid fossils were discovered in both Java and China. From publications the names “Peking Man” and “Java Man” are well known. Today, these are referred to as Homo erectus. They are known by their very prominent supraorbital torus and postorbital constriction, alveolar prognathism and receding chin. With the widest part of the skull toward the bottom, it has a pentagonal shape. The rest of the skeleton is very little different from the modern skeleton. Fossil bones from Europe are scarce, but the little that have been found correspond with Erectus from the Far East. They date from the Middle Pleistocene.

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15

Dimitrova, Tatyana. "Palynological analysis of the deposit Fosso Bianco, Central Italy". Geologica Balcanica 27, n.º 1-2 (30 de agosto de 1997): 101–4. http://dx.doi.org/10.52321/geolbalc.27.1-2.101.

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The palynological analysis of the Fosso Bianco section is based on the data obtained from 23 samples. Most of the samples contain polydominant and very rarely monodominant forest components. The palynological documentation is based on a classification of some well-known paleoflora groups. The comparative characteristics of the pollen spectra are based mainly on the data of the boundary Pliocene/Pleistocene in Central Italy.

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16

Hoselmann, Christian. "The Pliocene and Pleistocene fluvial evolution in the northern Upper Rhine Graben based on results of the research borehole at Viernheim (Hessen, Germany)". E&G Quaternary Science Journal 57, n.º 3/4 (1 de abril de 2009): 286–314. http://dx.doi.org/10.3285/eg.57.3-4.2.

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Abstract. The research borehole drilled in 2006 by the Hessian Agency for the Environment and Geology (HLUG) north of Viernheim (Hessisches Ried) reached a total depth of 350 m, and penetrated high resolution fluviatile and limnic-fluviatile sediments (0 to 225 m) of Pleistocene age, and partially highly pedogenically overprinted limnic-fluviatile sands, clays and silts of Pliocene age (225 to 350 m). The Pliocene sediments tend to be sourced locally. The sediments repeatedly show sourcing from the Odenwald which is characterised by a high percentage of green hornblende in the heavy mineral fraction. As part of the Heidelberg Basin research programme, one of the main purposes of this borehole was to analyse the Pleistocene “Normal Facies” of the northern Upper Rhine Graben, i.e. a sedimentary sequence subject to minimum disturbance, largely unaffected during the Pleistocene by material sourced from the graben margins or smaller tributaries. The Pleistocene sedimentary sequence consists of three units: a thin horizon with reworked Pliocene material is overlain by ten cycles each beginning erosively with gravely sandy sediments and ending with siltyargillaceous to in part peat-like sediments. Internal cycles can also be identified, amongst other features. A characteristic aspect is the green-grey, strongly calcareous, micaceous and well sorted, fi ne to medium sands of the Rhine. These are dominated by the Rhine Group (garnet, epidote, green hornblende and alterite) in the heavy mineral fraction. These sediments are classifi ed as the “Rhenish Facies”. The upper Pleistocene sedimentary sequences at the top of the Viernheim research borehole are dominated by several fi ning-upward and in part coarsening-upward sequences. The deposits in this part of the well are dominated by gravel deposited by the Neckar. The heavy mineral distribution of the sand fraction reveals, however, that there was mixing with Rhenish sediments. Weichselian to Holocene aeolian sands form the topmost part of the well section. The stratigraphic classifi cation of the Pleistocene sedimentary sequences is still uncertain in parts. The Pliocene-Pleistocene boundary is placed at 225 m because of the characteristic change in facies. Due to lithostratigraphic correlations with sediments within the Lower Rhine Embayment, a larger unconformity at the depth of 225 m must be accepted. Research carried out in the area around the well indicates that the youngest fine-clastic section penetrated by the well between 39.76 and 58.55 m is of Cromerian age.

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17

Karin, Benjamin R., Indraneil Das, Todd R. Jackman y Aaron M. Bauer. "Ancient divergence time estimates inEutropis rugiferasupport the existence of Pleistocene barriers on the exposed Sunda Shelf". PeerJ 5 (27 de octubre de 2017): e3762. http://dx.doi.org/10.7717/peerj.3762.

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Episodic sea level changes that repeatedly exposed and inundated the Sunda Shelf characterize the Pleistocene. Available evidence points to a more xeric central Sunda Shelf during periods of low sea levels, and despite the broad land connections that persisted during this time, some organisms are assumed to have faced barriers to dispersal between land-masses on the Sunda Shelf.Eutropis rugiferais a secretive, forest adapted scincid lizard that ranges across the Sunda Shelf. In this study, we sequenced one mitochondrial (ND2) and four nuclear (BRCA1,BRCA2,RAG1, andMC1R) markers and generated a time-calibrated phylogeny in BEAST to test whether divergence times between Sundaic populations ofE. rugiferaoccurred during Pleistocene sea-level changes, or if they predate the Pleistocene. We find thatE. rugiferashows pre-Pleistocene divergences between populations on different Sundaic land-masses. The earliest divergence withinE. rugiferaseparates the Philippine samples from the Sundaic samples approximately 16 Ma; the Philippine populations thus cannot be considered conspecific with Sundaic congeners. Sundaic populations diverged approximately 6 Ma, and populations within Borneo from Sabah and Sarawak separated approximately 4.5 Ma in the early Pliocene, followed by further cladogenesis in Sarawak through the Pleistocene. Divergence of peninsular Malaysian populations from the Mentawai Archipelago occurred approximately 5 Ma. Separation among island populations from the Mentawai Archipelago likely dates to the Pliocene/Pleistocene boundary approximately 3.5 Ma, and our samples from peninsular Malaysia appear to coalesce in the middle Pleistocene, about 1 Ma. Coupled with the monophyly of these populations, these divergence times suggest that despite consistent land-connections between these regions throughout the PleistoceneE. rugiferastill faced barriers to dispersal, which may be a result of environmental shifts that accompanied the sea-level changes.

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18

Le Pichon, Xavier, A. M. Celâl Şengör, Julia Kende, Caner İmren, Pierre Henry, Céline Grall y Hayrullah Karabulut. "Propagation of a strike-slip plate boundary within an extensional environment: the westward propagation of the North Anatolian Fault". Canadian Journal of Earth Sciences 53, n.º 11 (noviembre de 2016): 1416–39. http://dx.doi.org/10.1139/cjes-2015-0129.

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We document the establishment of the Aegea–Anatolia/Eurasia plate boundary in Pliocene–Pleistocene time. Before 2 Ma, no localized plate boundary existed north of the Aegean portion of the Anatolia plate and the shear produced by the motion of Anatolia–Aegea with respect to Eurasia was distributed over the whole width of the Aegean – West Anatolian western portion. In 4.5 Ma, a shear zone comparable to the Gulf of Corinth was formed in the present Sea of Marmara. The initial extensional basins were cut by the strike-slip Main Marmara Fault system after 2.5 Ma. Shortly after, the plate boundary migrated west of the Sea of Marmara along the northern border of Aegea from the North Aegean Trough, to the Gulf of Corinth area and to the Kefalonia Fault. There, it finally linked with the northern tip of the Aegean subduction zone, completing the system of plate boundaries delimiting the Anatolia–Aegea plate. We have related the change in the distribution of shear from Miocene to Pliocene to the formation of a relatively undeforming Aegea block in Pliocene that forced the shear to be distributed over a narrow plate boundary to the north of it. We attribute the formation of this block to the northeastward progression of the oceanic Ionian slab. We propose that the slab cuts the overlying lithosphere from asthenospheric sources and induces a shortening environment over it.

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19

Adeonipekun, Peter Adegbenga y Margaret Adebisi Sowunmi. "Palaeoclimatology and biostratigraphic significance of late Neogene/Quaternary vegetational changes recorded in the offshore western Niger Delta". Acta Palaeobotanica 59, n.º 2 (1 de diciembre de 2019): 373–90. http://dx.doi.org/10.2478/acpa-2019-0011.

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Abstract Attempts at reconstructing palaeoclimatic changes over time using palynomorphs of three oil wells drilled in the shallow offshore Niger Delta led to cluster analysis-aided recognition of seven pollen zones. These pollen zones are equivalent to ten palaeoclimatic zones with alternating dry and wet conditions. The palynomorphs were classified into phytoecological groups and changes in their relative abundances were employed to interpret the palaeoclimatic conditions of their source areas. Contrasting fluctuations in the proportions of the Spore (Pteridophytes) phytoecological group and those of the Poaceae were the main basis for palaeoclimatic inferences. Trends of the occurrence of other phytoecological groups were used to substantiate our palaeoclimatic inferences. In the latest Miocene (5.8–5.5 Ma), climatic conditions were mainly wet until between 5.5 and 5.0 Ma, when extreme dry conditions prevailed. The early Pliocene part (5.0–>3.4 Ma) was generally wet, while the late Pliocene part (<3.0–2.7 Ma) was extremely dry, with wet conditions re-occurring at the latest Pliocene/earliest Pleistocene boundary at a lower magnitude than those of the early Pliocene. This is inferred from the bloom of open vegetation Acanthaceae undif., Polygala sp. and Asystacia gangetica, along with montane Podocarpus milanjianus from 2.4 Ma through 2.0 Ma and younger. The Acanthaceae bloom recorded the evolution of A. gangetica in the latest Pliocene/earliest Pleistocene at around 2.0 Ma in the Niger Delta. The upper Early Pliocene regional wet event is associated with distinct peaks of riverine forest, freshwater swamp and mangrove pollen. Our results further support earlier findings from other parts of West Africa with respect to palaeoclimatic changes in the late Neogene/earliest Quaternary. Equivalent qualitative palynostratigraphic events were recognized within the pollen zones which are useful for age determination, and the significance of biostratigraphic correlation of the zones is stressed.

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20

Gebhardt, A. C., W. H. Geissler, J. Matthiessen y W. Jokat. "Changes in current patterns in the Fram Strait at the Pliocene/Pleistocene boundary". Quaternary Science Reviews 92 (mayo de 2014): 179–89. http://dx.doi.org/10.1016/j.quascirev.2013.07.015.

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21

Suc, Jean-Pierre, Adele Bertini, Suzanne A. G. Leroy y Danica Suballyova. "Towards the lowering of the Pliocene/Pleistocene boundary to the Gauss-Matuyama reversal". Quaternary International 40 (enero de 1997): 37–42. http://dx.doi.org/10.1016/s1040-6182(96)00059-6.

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22

Holden, Philip B., Neil R. Edwards, Thiago F. Rangel, Elisa B. Pereira, Giang T. Tran y Richard D. Wilkinson. "PALEO-PGEM v1.0: a statistical emulator of Pliocene–Pleistocene climate". Geoscientific Model Development 12, n.º 12 (10 de diciembre de 2019): 5137–55. http://dx.doi.org/10.5194/gmd-12-5137-2019.

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Abstract. We describe the development of the “Paleoclimate PLASIM-GENIE (Planet Simulator–Grid-Enabled Integrated Earth system model) emulator” PALEO-PGEM and its application to derive a downscaled high-resolution spatio-temporal description of the climate of the last 5×106 years. The 5×106-year time frame is interesting for a range of paleo-environmental questions, not least because it encompasses the evolution of humans. However, the choice of time frame was primarily pragmatic; tectonic changes can be neglected to first order, so that it is reasonable to consider climate forcing restricted to the Earth's orbital configuration, ice-sheet state, and the concentration of atmosphere CO2. The approach uses the Gaussian process emulation of the singular value decomposition of ensembles of the intermediate-complexity atmosphere–ocean GCM (general circulation model) PLASIM-GENIE. Spatial fields of bioclimatic variables of surface air temperature (warmest and coolest seasons) and precipitation (wettest and driest seasons) are emulated at 1000-year intervals, driven by time series of scalar boundary-condition forcing (CO2, orbit, and ice volume) and assuming the climate is in quasi-equilibrium. Paleoclimate anomalies at climate model resolution are interpolated onto the observed modern climatology to produce a high-resolution spatio-temporal paleoclimate reconstruction of the Pliocene–Pleistocene.

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Boessenecker, Robert W., Dana J. Ehret, Douglas J. Long, Morgan Churchill, Evan Martin y Sarah J. Boessenecker. "The Early Pliocene extinction of the mega-toothed shark Otodus megalodon: a view from the eastern North Pacific". PeerJ 7 (13 de febrero de 2019): e6088. http://dx.doi.org/10.7717/peerj.6088.

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The extinct giant shark Otodus megalodon is the last member of the predatory megatoothed lineage and is reported from Neogene sediments from nearly all continents. The timing of the extinction of Otodus megalodon is thought to be Pliocene, although reports of Pleistocene teeth fuel speculation that Otodus megalodon may still be extant. The longevity of the Otodus lineage (Paleocene to Pliocene) and its conspicuous absence in the modern fauna begs the question: when and why did this giant shark become extinct? Addressing this question requires a densely sampled marine vertebrate fossil record in concert with a robust geochronologic framework. Many historically important basins with stacked Otodus-bearing Neogene marine vertebrate fossil assemblages lack well-sampled and well-dated lower and upper Pliocene strata (e.g., Atlantic Coastal Plain). The fossil record of California, USA, and Baja California, Mexico, provides such an ideal sequence of assemblages preserved within well-dated lithostratigraphic sequences. This study reviews all records of Otodus megalodon from post-Messinian marine strata from western North America and evaluates their reliability. All post-Zanclean Otodus megalodon occurrences from the eastern North Pacific exhibit clear evidence of reworking or lack reliable provenance; the youngest reliable records of Otodus megalodon are early Pliocene, suggesting an extinction at the early-late Pliocene boundary (∼3.6 Ma), corresponding with youngest occurrences of Otodus megalodon in Japan, the North Atlantic, and Mediterranean. This study also reevaluates a published dataset, thoroughly vetting each occurrence and justifying the geochronologic age of each, as well as excluding several dubious records. Reanalysis of the dataset using optimal linear estimation resulted in a median extinction date of 3.51 Ma, somewhat older than a previously proposed Pliocene-Pleistocene extinction date (2.6 Ma). Post-middle Miocene oceanographic changes and cooling sea surface temperature may have resulted in range fragmentation, while alongside competition with the newly evolved great white shark (Carcharodon carcharias) during the Pliocene may have led to the demise of the megatoothed shark. Alternatively, these findings may also suggest a globally asynchronous extinction of Otodus megalodon.

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24

Konradi, Peter B. "Foraminiferal biostratigraphy of the post mid-Miocene in two boreholes in the Danish North Sea". Danmarks Geologiske Undersøgelse Serie C 12 (31 de diciembre de 1995): 101–11. http://dx.doi.org/10.34194/seriec.v12.7112.

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Cutting samples from two exploration wells, Cleo-1 and Kim-1, in the Central Trough area in the northwestern part of the Danish North Sea, have been investigated for foraminiferal content in the section above the prominent mid-Miocene event. Benthonic foraminifera have been used to produce a stratigraphic subdivision by reference to the standard NSB zonation of King. The NSB 12 to NSB 17 zones (Middle Miocene to Middle Pleistocene) have been identified above the event. These zones can be related to the paleo water depth zonation. Paleoenvironrnental reconstruction shows that sediments from the subject interval from Cleo-1 were deposited in a shallower situation than equivalent deposits in Kim-1. A conspicuous hiatus is identified in Cleo-1 at the Pliocene-Pleistocene boundary.

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25

Westaway, R. "Long-term river terrace sequences: Evidence for global increases in surface uplift rates in the Late Pliocene and early Middle Pleistocene caused by flow in the lower continental crust induced by surface processes". Netherlands Journal of Geosciences - Geologie en Mijnbouw 81, n.º 3-4 (diciembre de 2002): 305–28. http://dx.doi.org/10.1017/s0016774600022629.

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AbstractLong-term river terrace sequences reveal that many regions have uplifted by several hundred metres since the Middle Pliocene. They indeed provide evidence of a global increase in uplift rates in die Late Pliocene, followed by a calm period then a renewed increase around the Early-Middle Pleistocene boundary. It is suggested that this uplift pattern has resulted from thickening of the continental crust caused by flow in the lower crust which has been induced by cyclic surface loading caused by growth and decay of ice sheets and the associated global sea-level fluctuations. Observed uplift histories are modelled using a technique which incorporates increases in the strength of forcing of this process caused by step changes in the intensity of glaciations starting at~3.1,~2.5,~1.2, and~0.9 Ma.

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Kasuya, Masao. "Fission-Track Ages of Tuff Layers Related to the Pliocene-Pleistocene Boundary on the Boso Peninsula, Japan". Quaternary Research 33, n.º 1 (enero de 1990): 86–93. http://dx.doi.org/10.1016/0033-5894(90)90086-z.

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AbstractFission-track ages of zircon crystals from four tuff layers in the late Cenozoic sediment sequence of the Boso Peninsula,.Japan, are 1.6 ± 0.2 myr (the Kurotaki Formation), 5.5 ± 0.6 and 5.2 ± 0.5 myr (the uppermost part of the Amatsu Formation), and 11.5 ± 0.8 myr (the middle part of the Amatsu Formation). These ages provide numerical age constraints on magneto-biostratigraphy. The normal polarity interval in the lower part of the Kiwada Formation corresponds to the Olduvai polarity subzone. The boundary between the Pliocene and Pleistocene lies slightly above the Olduvai polarity subzone.

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27

Jenkins, D. Graham, John E. Whittaker y R. Carlton. "On the age and correlation of the St. Erth Beds, S.W. England, based on planktonic foraminifera". Journal of Micropalaeontology 5, n.º 2 (1 de diciembre de 1986): 93–105. http://dx.doi.org/10.1144/jm.5.2.93.

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Abstract. The paper illustrates and describes 15 species of planktonic foraminifera from the St. Erth Beds, Cornwall, S.W. England. The overlap of the stratigraphic ranges of Globorotalia inflata (d’Orbigny), G. praehirsuta Blow, G. tosaensis Takayanagi & Saito, Pulleniatina primalis Banner & Blow, Neogloboquadrina humerosa (Takayanagi & Saito) and dextrally coiled N. pachyderma (Ehrenberg) places the age of the fauna in the Globorotalia inflata Zone, Late Pliocene. The absence of Globorotalia puncticulata (Deshayes), G. truncatulinoides (d’Orbigny) and Neogloboquadrina atlantica (Berggren) confirms this age assignment and with the presence of G. inflata (d’Orbigny), the deposition of St. Erth beds can now be accurately placed at between 2.1 and 1.9 Ma. For this paper, it has been acceped that the Pliocene-Pleistocene boundary is marked by the first evolutionary appearance of G. truncatulinoides at about 1.9 Ma.

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Levchenko, O. V., Yu G. Marinova, M. V. Portnyagin, R. Werner y L. I. Lobkovsky. "New data on geology of the Osborn Knoll, Indian ocean". Доклады Академии наук 489, n.º 6 (23 de diciembre de 2019): 631–36. http://dx.doi.org/10.31857/s0869-56524896631-636.

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The Osborne Plateau is a large intraplate elevation in the eastern part of the Indian Ocean, which has been poorly studied by geological and geophysical methods. In cruise SO258/1 on RV Sonne, were collected new data with Parasound seismic proﬁling and multi-beam echo sounder survey. Fractures in the sedimentary cover, which extend to the bottom surface, indicate on high neotectonic activity in the area of the Osborne Plateau. It can continue up to the present, as well as in the adjacent segment of the Ninetyeast Ridge, where strong earthquakes are recorded. Two reflectors in the upper part of the sedimentary cover mark global regressive changes in the World Ocean level at the boundary of the Miocene / Pliocene and Pliocene / Pleistocene. The reflector in the sediments at the boundary of the Lower / Upper Pliocene is associated with a change in the regional hydrodynamic regime at the time in the eastern Indian Ocean. The rocks dragged on the Osborn Knoll are identical to volcanic rocks of the Ninetyeast Ridge, confirming their assumed genetic similarity, but they are more identical to basalts of the Kerguelen plateau. Extremely modified vitroclastic tuffs appear to have been formed as a result of explosive volcanic eruptions of alkaline basalts or foidites in subaeral or relatively shallow water conditions and represent the most recent eruption in the region.

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29

Likius, Andossa, Michel Brunet, Denis Geraads y Patrick Vignaud. "The oldest Camelidae (Mammalia, Artiodactyla) of Africa : new finds from the Mio-Pliocene boundary, Chad". Bulletin de la Société Géologique de France 174, n.º 2 (1 de marzo de 2003): 187–93. http://dx.doi.org/10.2113/174.2.187.

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Abstract A fragment of mandible and two metapodials complete unearthed from the fossiliferous aera of Kossom Bougoudi (KB3 and KB26), northern Chad are described. A comparative study allows to assign these specimens to Paracamelus gigas. The evolutionnary degree is compatible with an age around the Mio-Pliocene boundary (ca 5 Ma). Then, the Chadian remains are the oldest adequately dated record of this family in Africa. They are contemporaneous with the oldest known evidence of the genus Paracamelus from the late Miocene of Asia and Europe. Introduction. – During several field seasons in northern Chad, the “Mission Paléoanthropologique Franco-Tchadienne” (M. P. F. T) discovered new sites in the Kossom Bougoudi (KB) fossiliferous area, west of australopithecine sites [Brunet et al., 1995, 1997; Brunet and M.P.F.T, 2000]. These sites yielded a rich vertebrate fauna (fish, reptiles, birds and mammals), and have been biochronologically dated at around 5 Ma old, close to the Mio-Pliocene boundary [Brunet and M. P. F.T, 2000]. Among the mammal fauna, some remains of Camelidae provide the earliest evidence of this group in Africa, which was previously thought to be younger than 4 Ma, at Laetoli [Harris, 1987] and Koobi Fora [Harris, 1991]. Specimens from sites KB3 and KB26 are described here. Description Material : KB3.97.316 : right mandible fragment with p3, p4-m1 roots and m2-m3 teeth; KB3.99.03 : right metatarsus; KB26.97.03 : right metatarsus The mandible is rather robust with a high horizontal ramus. The mental foramen is located below m1. The p3 alveolus and p4 roots attest elongated premolars. The lingual face of the molars is flat. The third lobe of m3 is less labially shifted than in the living camels. There is no cement, nor cingulum. The metatarsals are long and robust (tab. III), and show a deep groove on the proximal anterior and posterior faces. The distal condyles are divergent and separated by a deep interarticular notch. They are symmetrical and of the same size differences, in contrast with the extant species where the external condyle is more slender than the internal one. Comparison. – The mandible (KB3.97.316) differs from the Camelus species mandible by having (1) a robust and deeper horizontal ramus, (2) a well developed p3, (3) a third lobe of m3 less labially shifted (4) Chadian metatarsals are morphologically different from those the living camels and being extremely long (tab. II). All characters of the Chadian specimens are congruent with Zdansky’s [1926] and Teilhard and Trassaert’s [1937] descriptions of genus Paracamelus. The KB horizontal ramus is deeper than that of P. alutensis (tab. I) from the early Pleistocene of Oltet Valley, Romania [Stefanescu, 1910]. The premolar row is longer. Unfortunately, a detailed comparison with P. aguirrei from the late Miocene (MN13) of Venta del Moro and Librilla, Spain is impossible because this species was defined on skeletal elements (upper molars, calcaneum, phalanxes) not yet recovered from Chad. However, the estimated alveolar length of p3 (20 mm) is similar to those of P. aguirrei (18,8 – 21,6 mm according to Morales [1984]). Lengths of KB tooth row (tab. I) and metatarsals (tab. II) fit into the range of variation recorded by Zdansky [1926] and by Teilhard and Trassaert [1937] for P. gigas from the late Miocene of China. The Chadian material cannot be assigned to the species P. alexejevi from the Pliocene (MN15) of Ukraine, because this species is smaller than P. aguirrei and P. gigas [Morales, 1984]. In conclusion, specimens from Chad do not display any important difference with Chinese species P. gigas and can tentatively be referred to this species. Biochronology and paleobiogeography. – The earliest known Old World camel correspond to P. aguirrei from the late Miocene (MN13) of Venta del Moro and Librilla in Spain [Morales et al., 1980; Made and Morales, 1999]. After Made and Morales [1999], this species is probably the ancestor of P. alexejevi from of Odessa Catacombs (MN15), Ukraine. In Europe, the chronological range of P. alutensis covers the Plio-Pleistocene. This species is present in the lower Pleistocene of Oltet Valley, Romania [Stefanescu, 1910] and in the early and Middle Pliocene (MN16) of Russia [Baigusheva, 1971]. It is also present in the late Pliocene of Sarikol Tepe, Turkey [Kostopoulos and Sen, 1999]. In China, the earliest record of P. gigas is about 5.5 Ma [Flynn, 1997; Made and Morales, 1999]. In conclusion the chronological range of Paracamelus is from the late Miocene to the Pleistocene. However, the Chadian specimens size is close to P. gigas (first occurrence in China around 5.5 Ma) and P. aguirrei from late Miocene (MN13) of Europe. The occurrence of Paracamelus at KB and its absence from the younger Chadian sites (3-4 Ma) of Koro-Toro and Kollé [Brunet et al., 1995; 1996] as well as in the Plio-Pleistocene localities of Africa, are congruent with an age close to the Mio-Pliocene boundary for the sites of KB. This interpretation is confirmed by the associated fauna, that indicates ca 5 Ma old for the whole of KB fossiliferous area [Brunet and M.P.F.T, 2000]. The age of the Chadian Paracamelus is close to the Mio-Pliocene boundary, slightly younger than specimens from late Miocene of China [Zdansky, 1926; Flynn, 1997], Spain [Morales et al., 1980] and Turkey [Made et al., 2002]. This demonstrates that the group had a wider distribution than previously thought. It indicates that the Camelidae reach a widespread distribution soon after their arrival from northern America [Webb, 1965; Pickford et al., 1993]. Conclusion. – The Chadian material displays distinctive features which allows to refer it to Paracamelus gigas. This taxon, poorly documented in Eurasia, has not been previously recognised in Africa. It will contribute to deciphering the phylogenetic relationships between various species of Paracamelus and the extant Camelus.

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30

Dey, Rikee, Amit K. Ghosh, Ajoy Kumar Bhaumik, Arindam Chakraborty, Stuti Saxena y Lopamudra Roy. "Late Pliocene to Early Pleistocene Planktonic Foraminifera from Northern Indian Ocean (Andaman and Nicobar Islands): Interpretation on Cooling Event and Ocean Upwelling". Journal of Foraminiferal Research 51, n.º 3 (31 de julio de 2021): 115–38. http://dx.doi.org/10.2113/gsjfr.51.3.115.

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ABSTRACT Thirty-two planktonic foraminiferal taxa have been identified based on Bright Field microscopic study as well as Scanning Electron Microscopy on the samples collected from the outcrop adjacent to the type section of Neill West Coast Formation at Neil Island of Ritchie's Archipelago, northern Indian Ocean. The planktonic foraminiferal taxa belong to ten genera viz., Dentoglobigerina, Globigerina, Globigerinoides, Globoconella, Globorotalia, Globorotaloides, Globoturborotalita, Neogloboquadrina, Orbulina, and Trilobatus. A number of statistical analyses have been done in addition to taxonomic study to interpret the palaeocenographic scenario. We performed PCA analysis on the foraminiferal content of the samples to test the relatedness. Two biozones have been established by Stratigraphically Constrained Cluster Analysis (CONISS). We used SHEBI (SHE analysis for biozone identification) analysis to precisely demarcate seven biozones. Attempts have been made to decipher the Plio–Pleistocene boundary in the Neill West Coast Formation based on specific zonal markers. The presence of some taxa (e.g., Globoconella inflata, Globigerina bulloides, and Neogloboquadrina pachyderma) indicates the initiation of a cooling event from late Pliocene onwards. An event of ocean upwelling also has been identified based on the presence of Globigerina bulloides, Neogloboquadrina pachyderma, and N. dutertrei from the late Pliocene to early Pleistocene of the northern Indian Ocean that also correlates with palaeoceanographic records known from other upwelling regions.

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31

Alexeeva, Nadezhda V. y Margarita A. Erbajeva. "Changes in the fossil mammal faunas of Western Transbaikalia during the Pliocene–Pleistocene boundary and the Early–Middle Pleistocene transition". Quaternary International 131, n.º 1 (enero de 2005): 109–15. http://dx.doi.org/10.1016/j.quaint.2004.07.002.

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32

Oshida, Tatsuo, Wynn Than, Thida Oo, Khin Yu Yu Swe, Hiroaki Saito, Masaharu Motokawa, Junpei Kimura, Son Truong Nguyen, Hai Tuan Bui y Phuong Huy Dang. "Phylogenetic relationships among Callosciurus squirrels in the Indochina Peninsula: phylogenetic position of C. pygerythrus from Myanmar". Acta Zoologica Academiae Scientiarum Hungaricae 67, n.º 1 (22 de febrero de 2021): 87–98. http://dx.doi.org/10.17109/azh.67.1.87.2021.

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The phylogenetic relationships among seven Callosciurus species from the Indochina Peninsula, including the C. honkhoaiensis which is endemic to Hon Khoai Island, were studied using complete mitochondrial cytochrome b gene sequences (1140 bases). We primarily focused on the phylogenetic position of C. pygerythrus, which is distributed in the western part of the peninsula. We identified two main lineages: 1) C. caniceps, C. honkhoaiensis, C. inornatus, C. phayrei and C. pygerythrus, and 2) C. erythraeus and C. finlaysonii. Estimated divergence time between the two lineages was at the junction of the Zanclean and Piacenzian in the Pliocene. Within the first linage, the divergence time of sub-lineages corresponded to the Pliocene-Pleistocene boundary, although phylogenetic relationships were unclear. These two divergence times estimated in the present study correspond to episodes of global cooling, suggesting that climate may have contributed to the divergence of these Callosciurus squirrels.

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33

Routledge, Claire M., Denise K. Kulhanek, Lisa Tauxe, Giancarlo Scardia, Arun D. Singh, Stephan Steinke, Elizabeth M. Griffith y Rajeev Saraswat. "A revised chronostratigraphic framework for International Ocean Discovery Program Expedition 355 sites in Laxmi Basin, eastern Arabian Sea". Geological Magazine 157, n.º 6 (10 de abril de 2019): 961–78. http://dx.doi.org/10.1017/s0016756819000104.

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AbstractInternational Ocean Discovery Program Expedition 355 drilled Sites U1456 and U1457 in Laxmi Basin (eastern Arabian Sea) to document the impact of the South Asian monsoon on weathering and erosion of the Himalaya. We revised the chronostratigraphic framework for these sites using a combination of biostratigraphy, magnetostratigraphy and strontium isotope stratigraphy. The sedimentary section at the two sites is similar and we divided it into six units bounded by unconformities or emplaced as a mass-transport deposit (MTD). Unit 1 underlies the MTD, and is of early–middle Miocene age at Site U1456 and early Paleocene age at Site U1457. An unconformity (U1) created by emplacement of the MTD (unit 2) during the late Miocene Epoch (at c. 9.83–9.69 Ma) separates units 1 and 2 and is identified by a marked change in lithology. Unit 3 consists of hemipelagic sediment with thin interbeds of graded sandstone of late Miocene age, separated from unit 4 by a second unconformity (U2) of 0.5–0.9 Myr duration. Unit 4 consists of upper Miocene interbedded mudstone and sandstone and hemipelagic chalk deposited between c. 8 and 6 Ma. A c. 1.4–1.6 Myr hiatus (U3) encompasses the Miocene–Pliocene boundary and separates unit 4 from unit 5. Unit 5 includes upper Pliocene – lower Pleistocene siliciclastic sediment that is separated from unit 6 by a c. 0.45 Myr hiatus (U4) in the lower Pleistocene sediments. Unit 6 includes a thick package of rapidly deposited Pleistocene sand and mud overlain by predominantly hemipelagic sediment deposited since c. 1.2 Ma.

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34

Satoguchi, Yasufumi, Chiyomi Yamakawa y Keiichi Takahashi. "The old and newly defined Pliocene-Pleistocene boundary sites of the Kobiwako Group, central Japan". Journal of the Geological Society of Japan 118, Supplement (2012): S70—S78. http://dx.doi.org/10.5575/geosoc.2012.0035.

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35

Shackleton, N. J., A. Berger y W. R. Peltier. "An alternative astronomical calibration of the lower Pleistocene timescale based on ODP Site 677". Transactions of the Royal Society of Edinburgh: Earth Sciences 81, n.º 4 (1990): 251–61. http://dx.doi.org/10.1017/s0263593300020782.

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ABSTRACTOcean Drilling Program (ODP) Site 677 provided excellent material for high resolution stable isotope analysis of both benthonic and planktonic foraminifera through the entire Pleistocene and upper Pliocene. The oxygen isotope record is readily correlated with the SPECMAP stack (Imbrie et al. 1984) and with the record from DSDP 607 (Ruddiman et al. 1986) but a significantly better match with orbital models is obtained by departing from the timescale proposed by these authors below Stage 16 (620 000 years). It is the stronger contribution from the precession signal in the record from ODP Site 677 that provides the basis for the revised timescale. Our proposed modification to the timescale would imply that the currently adopted radiometric dates for the Matuyama–Brunhes boundary, the Jaramillo and Olduvai Subchrons and the Gauss–Matuyama boundary underestimate their true astronomical ages by between 5 and 7%.

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36

Huang, Feixin, Xiaohan Liu, Ping Kong, David Fink, Yitai Ju, Aimin Fang, Liangjun Yu, Xiaoli Li y Chunguang Na. "Fluctuation history of the interior East Antarctic Ice Sheet since mid-Pliocene". Antarctic Science 20, n.º 2 (10 de enero de 2008): 197–203. http://dx.doi.org/10.1017/s0954102007000910.

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AbstractCosmogenic 10Be and 26Al measurements from bedrock exposures in East Antarctica provide indications of how long the rock surface has been free from glacial cover. Samples from the crests of Zakharoff Ridge and Mount Harding, two typical nunataks in the Grove Mountains, show minimum 10Be ages of 2.00 ± 0.22 and 2.30 ± 0.26 Ma, respectively. These ages suggest that the crests were above the ice sheet at least since the Plio–Pleistocene boundary. Adopting a ‘reasonable’ erosion rate of 5–10 cm Ma-1 increases the exposure ages of these two samples to extend into the mid-Pliocene. The bedrock exposure ages steadily decrease with decreasing elevation on the two nunataks, which indicates ~200 m decrease of the ice sheet in the Grove Mountains since mid-Pliocene time. Seven higher elevation samples exhibit a simple exposure history, which indicates that the ice sheet in the Grove Mountains decreased only ~100 m over a period as long as 1–2 Ma. This suggests that the East Antarctic Ice Sheet (EAIS) was relatively stable during the Pliocene warm interval. Five lower elevation samples suggest a complex exposure history, and indicate that the maximum subsequent increase of the EAIS was only 100 m higher than the present ice surface. Considering the uncertainties, their total initial exposure and subsequent burial time could be later than mid-Pliocene, which may not conflict with the stable mid-Pliocene scenario.

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37

Aguirre, Julio, Robert Riding y Juan C. Braga. "Diversity of coralline red algae: origination and extinction patterns from the Early Cretaceous to the Pleistocene". Paleobiology 26, n.º 4 (2000): 651–67. http://dx.doi.org/10.1666/0094-8373(2000)026<0651:docrao>2.0.co;2.

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Data from a comprehensive literature survey for the first time provide stage-level resolution of Early Cretaceous through Pleistocene species diversity for nongeniculate coralline algae. Distributions of a total of 655 species in 23 genera were compiled from 222 publications. These represent three family-subfamily groupings each with distinctive present-day distributions: (1) Sporolithaceae, low latitude, mainly deep water; (2) Melobesioid corallinaceans, high latitude, shallow water, to low latitude, deep water; (3) Lithophylloid/mastophoroid corallinaceans, mid- to low latitude, shallow water.Raw data show overall Early Cretaceous-early Miocene increase to 245 species in the Aquitanian, followed by collapse to only 43 species in the late Pliocene. Rarefaction analysis confirms the pattern of increase but suggests that scarcity of publications exaggerates Neogene decline, which was actually relatively slight.Throughout the history of coralline species, species richness broadly correlates with published global paleotemperatures based on benthic foraminifer δ18O values. The warm-water Sporolithaceae were most species-abundant during the Cretaceous, but they declined and were rapidly overtaken by the Corallinaceae as Cenozoic temperatures declined.Trends within the Corallinaceae during the Cenozoic appear to reflect environmental change and disturbance. Cool- and deep-water melobesioids rapidly expanded during the latest Cretaceous and Paleocene. Warmer-water lithophylloid/mastophoroid species increased slowly during the same period but more quickly in the early Oligocene, possibly reflecting habitat partitioning as climatic belts differentiated and scleractinian reef development expanded near the Eocene/Oligocene boundary. Melobesioids abruptly declined in the late Pliocene-Pleistocene, while lithophylloid/mastophoroids increased again. Possibly, onset of glaciation in the Northern Hemisphere (~2.4 Ma) sustained or accentuated latitudinal differentiation and global climatic deterioration, disrupting high-latitude melobesioid habitats. Simultaneously, this could have caused moderate environmental disturbance in mid- to low-latitude ecosystems, promoting diversification of lithophylloids/mastophoroids through the “fission effect.”Extinction events that eliminated >20% of coralline species were most severe (58–67% of species) during the Late Cretaceous and late Miocene-Pliocene. Each extinction was followed by substantial episodes of origination, particularly in the Danian and Pleistocene.

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38

Pini, Roberta. "A tribute to Menke (1970): Results of pollen analysis on the Pleistocene stratigraphy and the Pliocene–Pleistocene boundary in Schleswig-Holstein". E&G Quaternary Science Journal 70, n.º 2 (17 de diciembre de 2021): 239–42. http://dx.doi.org/10.5194/egqsj-70-239-2021.

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39

Sardella, Raffaele y Maria Rita Palombo. "The Pliocene-Pleistocene boundary: which significance for the so called “Wolf Event”? Evidences from Western Europe". Quaternaire, n.º 18/1 (1 de marzo de 2007): 65–71. http://dx.doi.org/10.4000/quaternaire.969.

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40

Hennissen, Jan A. I., Martin J. Head, Stijn De Schepper y Jeroen Groeneveld. "Increased seasonality during the intensification of Northern Hemisphere glaciation at the Pliocene–Pleistocene boundary ∼2.6 Ma". Quaternary Science Reviews 129 (diciembre de 2015): 321–32. http://dx.doi.org/10.1016/j.quascirev.2015.10.010.

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41

Fostowicz-Frelik, Łucja y Grzegorz J. Frelik. "The earliest occurrence of the steppe pika (Ochotona pusilla) in Europe near the Pliocene/Pleistocene boundary". Naturwissenschaften 97, n.º 3 (19 de diciembre de 2009): 325–29. http://dx.doi.org/10.1007/s00114-009-0634-6.

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42

Pedersen, Anette Mønsted. "Foraminiferal biozonation in the Early Pleistocene in the Central North Sea". Danmarks Geologiske Undersøgelse Serie C 13 (31 de diciembre de 1995): 1–56. http://dx.doi.org/10.34194/seriec.v13.7116.

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Pliocene and Pleistocene deposits from 66 boreholes from the central and northern North Sea have been examined for their content of benthic foraminifera. In this area the Pliocene/Pleistocene boundary is generally placed at the bottom or middle of the Elphidium oregonense Subzone or at the last local occurrence of Cibicides grossus. A detailed study of the temporal relationship between these two species in the western part of the Danish sector shows, that the last local occurrence of Cibicides grossus in this area is older than the Elphidium oregonense Subzone. On the basis of the results concerning the Lower Pleistocene an emendation of the foraminiferal biostratigraphy for this sub-series is proposed and related to previous work on the biostratigraphy and palaeogeography of the North Sea area. The investigation indicates the existence of two distinct new subzones within the Elphidiella hannai/Cassidulina teretis range: The oldest of the two new subzones is an Acme-zone with Buliminidae as the characteristic taxon, and it is named the Stainforthia/Bulimina Subzone. The depositional environment was a boreal shelf with a water depth presumed to exceed 100 m. Based on its stratigraphic position and enviromental indications the Subzone is referred to the Tiglian stage. The youngest of the two new subzones is a local Range-zone, defined by the presence of the arctic species Elphidiella gorbunovi, and it is named the Elphidiella gorbunovi Subzone. The depositional environment was an arctic shelf with a water depth of less than 50 m. The occurrence of Elphidiella gorbunovi in the central North Sea thus indicates a cold interval in either the Eburonian or the Menapian stage. Succeeding the Elphidiella gorbunovi Subzone, the foraminiferal fauna and the sediment indicate increasingly near-coastal environment and a warming of the climate.

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43

MacFadden, Bruce J., Michael J. Whitelaw, Phil McFadden y Thomas H. V. Rich. "Magnetic Polarity Stratigraphy of the Pleistocene Section at Portland (Victoria), Australia". Quaternary Research 28, n.º 3 (noviembre de 1987): 364–73. http://dx.doi.org/10.1016/0033-5894(87)90004-4.

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AbstractThree to seven oriented paleomagnetic samples were collected from 16 sites in the Nelson Bay and Bridgewater formations at Portland, Victoria, which contains the recently discovered Nelson Bay local fauna (L.F.). The entire section has reversed polarity. These results, along with Globorotalia truncatulinoides within the section, and the presence of underlying middle Pliocene-dated basalts, indicate that the Portland section, and the included Nelson Bay L.F., was deposited within the late Matuyama Chron between 1.66 and 0.73 myr ago. This represents the first well-documented pre-14C Pleistocene mammalian fauna in Australia calibrated in direct stratigraphic context with absolute dating methods. In addition, the reversed polarity for the Bridgewater Formation confirms the previous hypothesis that the depositional history of this beach-sand deposit is time-transgressive across the Brunhes-Matuyama boundary.

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44

Schönfeld, Joachim. "Biostratigraphy and assemblage composition of benthic foraminifera from the Manihiki Plateau, southwestern tropical Pacific". Journal of Micropalaeontology 14, n.º 2 (1 de octubre de 1995): 165–75. http://dx.doi.org/10.1144/jm.14.2.165.

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Abstract. Pleistocene and late Pliocene benthic foraminifera from the Manihiki Plateau (southwestern tropical Pacific) were studied at piston-core 34KL. A new benthic foraminiferal biozonation is proposed. It comprises the Nodogenerina sagriensis Partial Range Zone from core base to 566.5 cm and the Fissurina seminiformis Partial Range Zone from this level to core top. The boundary is defined by the last occurence of Nodogenerina sagriensis which is time equivalent to the ‘Stilostomella extinction’ in the Eastern Atlantic. High abundances of Cibicidoides wuellerstorfi indicate a strong influence of near-bottom currents. The absence of high-productivity sensitive species reveals a low flux of organic matter to the sea floor from which a considerable amount is adduced by lateral advection.

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45

Marks, Leszek, Jan Dzierżek, Robert Janiszewski, Jarosław Kaczorowski, Leszek Lindner, Aleksandra Majecka, Michał Makos, Marcin Szymanek, Anna Tołoczko-Pasek y Barbara Woronko. "Quaternary stratigraphy and palaeogeography of Poland". Acta Geologica Polonica 66, n.º 3 (1 de septiembre de 2016): 410–34. http://dx.doi.org/10.1515/agp-2016-0018.

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Abstract Though the stratigraphical and palaeogeographical framework of the Quaternary in Poland is still to be completed, several crucial points have been confirmed recently. The preglacial series, accepted for years as belonging to the Lower Pleistocene, is undoubtedly of Early Pliocene age, with a huge hiatus above almost until the uppermost Lower Pleistocene. The earliest glaciation in Poland (Nidanian) occurred at about 900 ka BP when the ice sheet reached the mid-southern part of the country. The following Podlasian Interglacial embraced the Brunhes/Matuyama boundary in the middle, in a similar fashion to the corresponding Cromerian Complex in Western Europe. The late Early and early Middle Pleistocene interglacials in Poland comprised 2–3 optima each, whereas every one of the younger interglacials was characterised by a single optimum only. The Late Vistulian ice sheet was most extensive in the western part of Poland (Leszno Phase) whereas the younger Poznań Phase was more extensive in the central and eastern part of the country. This was due to the varied distance from the glaciation center in Scandinavia, making the ice sheet margin reach a terminal position in different times. Palaeoclimatological research in the Tatra Mountains has provided new evidence for the atmospheric circulation over Europe. During cold phases of the Pleistocene in Poland a continental climate extended further westwards, quite the opposite that occurring during warmer intervals.

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46

Landau, Bernard, Carlos Marques Da Silva y Geerat Vermeij. "Pacific elements in the Caribbean Neogene gastropod fauna: the source-sink model, larval development, disappearance, and faunal units". Bulletin de la Société Géologique de France 180, n.º 4 (1 de julio de 2009): 343–52. http://dx.doi.org/10.2113/gssgfbull.180.4.343.

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Abstract A key fact in the history of Neogene Caribbean marine molluscs is the disappearance of the “paciphile” taxa that occurred throughout Tropical America during the Miocene and the Pliocene, but subsequently suffered a range contraction, and became largely or entirely restricted to the eastern Pacific portion of their original distribution. What forces led to the disappearance of these paciphile taxa in the Atlantic portion of their original distribution is at present unclear, as there seem to be no obvious common environmental factor or ecological requirements uniting this paciphilic assemblage of taxa. It is suggested that for paciphile species the emergence of the isthmus during the Late Pliocene cut off the source populations of the planktonically-dispersing molluscs dependent on Pacific source populations. The sink populations thus became stranded on the Atlantic coast of South America and elsewhere in the Caribbean, where they became unsustainable and eventually disappeared. A reappraisal of all known paciphile species indicates an inferred planktotrophic larval development, which supports this hypothesis. Paciphiles did not disappear simultaneously, but seem to have suffered a steep decline during the Late Pliocene. A revision of all known gastropod paciphile generic, subgeneric and specific taxa allowed us to recognise three Gatunian Neogene Paciphile Molluscan Units (GNPMU). GNPMU 1 is characterized by the highest number of paciphile taxa. This unit is already in place in the Early Miocene and ends at the beginning of the Late Pliocene. GNPMU 2 is characterized by an impoverished number of paciphilic elements, devoid of the two largest paciphilic groups; the cancellarids and the muricids. This unit straddled the Pliocene-Pleistocene boundary and ends during the Early Pleistocene. GNPMU 3 is characterized by the absence of any paciphilic elements in their assemblages, and runs into Recent times. Based on these paciphile generic, subgeneric and specific taxa, for the Gatunian Province, two pulses of local disappearance from the Atlantic portion of their original distribution can be identified. The first marked by the overall decrease in Atlantic paciphile diversity and the total disappearance of all the paciphilic cancellarids and muricids, roughly corresponding with the timing given for the closure of the CAS. The second marked by the complete disappearance of all paciphiles from the Atlantic roughly coincides with the total closure of all connections between the Atlantic and Pacific.

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Crippa, Gaia, Michele Azzarone, Cinzia Bottini, Stefania Crespi, Fabrizio Felletti, Mattia Marini, Maria Rose Petrizzo, Daniele Scarponi, Sergio Raffi y Gianluca Raineri. "Bio- and lithostratigraphy of lower Pleistocene marine successions in western Emilia (Italy) and their implications for the first occurrence of Arctica islandica in the Mediterranean Sea". Quaternary Research 92, n.º 2 (14 de mayo de 2019): 549–69. http://dx.doi.org/10.1017/qua.2019.20.

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AbstractThe Arda and Stirone marine successions (Italy) represent key sections for the early Pleistocene; they were deposited continuously within a frame of climate change, recording the Calabrian cooling as testified by the occurrence of the “northern guests,” such as the bivalve Arctica islandica. In addition, although the first occurrence of A. islandica in the Mediterranean Sea was used as the main criterion to mark the former Pliocene-Pleistocene boundary, the age of this bioevent was never well constrained. Here, we describe the Stirone depositional environment and constrain for the first time the section age using calcareous nannofossil and foraminifera biostratigraphy. We also correlate the Arda and Stirone sections using complementary biostratigraphic and magnetostratigraphic data. Our results indicate that A. islandica first occurred in both the successions slightly below the top of the CNPL7 biozone (dated at 1.71 Ma). Comparisons with other lower Pleistocene Mediterranean marine successions indicate that the stratigraphically lowest level where A. islandica first occurred in the Mediterranean Sea is in the Arda and Stirone sections; these environments satisfied the ecological requirements for the establishment and the proliferation of the species, which only subsequently (late Calabrian) has been retrieved in southern Italy and other areas of the Mediterranean Sea.

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Chiyonobu, Shun, Masayuki Torii, Jumpei Morimoto y Motoyoshi Oda. "The Pliocene/Pleistocene boundary of the upper Takanabe Formation of the Miyazaki Group, southern Kyushu, Southwest Japan". Journal of the Geological Society of Japan 118, n.º 2 (2012): I—II. http://dx.doi.org/10.5575/geosoc.118.2.i_ii.

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Ning, Shi, Cao Jia-Xin y Lars-König Königsson. "Late Cenozoic Vegetational History and the Pliocene-Pleistocene Boundary in the Yushe Basin, S. E. Shanxi, China". Grana 32, n.º 4-5 (enero de 1993): 260–71. http://dx.doi.org/10.1080/00173139309429990.

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Angelone, Chiara, Stanislav Čermák, Blanca Moncunill-Solé, Josep Quintana, Caterinella Tuveri, Marisa Arca y Tassos Kotsakis. "Systematics and paleobiogeography of Sardolagus obscurus n. gen. n. sp. (Leporidae, Lagomorpha) from the early Pleistocene of Sardinia". Journal of Paleontology 92, n.º 3 (26 de marzo de 2018): 506–22. http://dx.doi.org/10.1017/jpa.2017.144.

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AbstractThe extreme rareness of Sardinian fossil sites older than Middle and Late Pleistocene makes the Monte Tuttavista karst complex (E Sardinia, Italy) very important. Remarkable lagomorph material, recovered from several fissure infillings of Monte Tuttavista referable to the Capo Figari/Orosei 1 and Orosei 2 faunal sub-complexes (early Pleistocene, ~2.1/1.9–1.1 Ma), allowed us to describe a new endemic insular leporid, Sardolagus obscurus n. gen. n. sp. The new taxon is characterized by a peculiar combination of an advanced p3 (Lepus-type) and a primitive P2 lacking deep flexa. The origin of such discrepancy, unprecedented among continental and insular endemic European leporids, is unclear. It could be the result of: (1) an independent evolution of p3 from an ancestor bearing the primitive P2/p3 (e.g., Alilepus, Hypolagus), or (2) a selective reversal morphocline from an Oryctolagus/Lepus-like leporine. The lack of data about the phylogenetic origin of the new taxon makes any inference about its possible arrival to Sardinia problematic. Crossing the European leporid records and evidence of migrations to Sardinia, we hypothesize three possible ages in which the ancestor of Sardolagus obscurus could have arrived in Sardinia, restricted to the late Miocene–early/late Pliocene (~8–3.6 Ma). The phylogenetic relationship between Sardolagus obscurus n. gen. n. sp. and the oldest Sardinian leporid, recorded from Capo Mannu D1 and dated at the early/late Pliocene boundary (~3.6 Ma), is unclear at present, however it is quite likely that they pertain to the same lineage.UUID: http://zoobank.org/ca8e0023-7c9d-4b00-a294-d166c37c5c71

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