scholarly journals Stratigraphy, palaeoenyironmental interpretation and uplift history of Barbados based on foraminiferal and other palaeontological evidence

2009 ◽  
Vol 28 (1) ◽  
pp. 37-44 ◽  
Author(s):  
R. W. Jones

Abstract. The ages and environments of deposition of the principal mapped units of Barbados, based on foraminiferal and other palaeontological evidence, are discussed, together with the uplift history of the island. The age of the Scotland Formation is demonstrated to be Paleocene to ?early Middle Eocene; that of the Oceanic Formation late Middle Eocene to early Early Miocene; that of the Bissex Hill Formation and Conset Marl late Early to early Late Miocene; and that of the Coral Rock Formation Middle–Late Pleistocene. The environment of deposition of the Scotland Formation is interpreted to be abyssal; that of the Oceanic Formation abyssal to be lower bathyal; that of the Bissex Hill Formation and Conset Marl middle to lower bathyal; and that of the Coral Rock Formation inner neritic. Observed elevation/age relationships imply a mean uplift rate of between 120 m Ma−1 and 220 m Ma−1.

2021 ◽  
Author(s):  
Chihao Chen ◽  
Yan Bai ◽  
Xiaomin Fang ◽  
Haichao Guo ◽  
Weilin Zhang ◽  
...  

<p>As an important driver of global climate change during the Cenozoic, the uplift of the Tibetan Plateau (TP) has strongly influenced the origination and evolution of the Asian monsoon system, and therefore the aridification of central Asia. Over the last two decades, the application of stable isotope paleoaltimeters and the discoveries of mammal and plant fossils have greatly promoted the understanding of the uplift history of the TP. However, paleoaltitudinal reconstructions based on different paleoaltimeters have suggested differing outcomes and therefore remain controversial. Novel paleoaltimeters have therefore needed to be developed and applied to constrain the uplift history of the TP more accurately and effectively by comparing and verifying multi-proxies. Paleothermometers based on glyceryl dialkyl glycerol tetraethers (GDGTs) are widely used in terrestrial and ocean temperature reconstructions. In this study, GDGT-based paleothermometers were tentatively applied to the Gyirong Basin on the southern TP, and the Xining Basins on the northern TP, in an attempt to quantitatively reconstruct their paleoaltitudes.</p><p>Both soil and aquatic-typed branched GDGTs have been identified from Late Miocene to Mid-Pliocene (7.0-3.2 Ma) samples taken from the Gyirong Basin; their reconstructed paleotemperatures were 7.5±3.3°C and 14.2±4.5°C, respectively. The former temperature may represent the mean temperature of the terrestrial organic matter input area, while the latter may represent the lake surface temperature. The results would suggest that the lake surface of the Gyirong Basin during the Late Miocene to Mid-Pliocene was 2.5±0.8 km and that the surrounding mountains exceeded 3.6±0.6 km, implying that the central Himalayas underwent a rapid uplift of ~1.5 km after the Mid-Pliocene.</p><p>GDGT-based paleotemperature reconstructions using MBT'<sub>5ME</sub> values show that the Xining Basin dropped in temperature by ~10°C during the ~10.5-8 Ma period, exceeding that in sea surface temperatures and low-altitude terrestrial temperatures during these periods. By combining these results with contemporaneous tectonic and sedimentary records, we infer that these cooling events signaled the regional uplift with the amplitude of ~1 km of the Xining basins. Our results support that the TP was still growing and uplifting substantially since the Late Miocene, which may provide new evidence for understanding the growth, expansion and uplift patterns of the TP.</p>


Geologos ◽  
2013 ◽  
Vol 19 (4) ◽  
pp. 273-290 ◽  
Author(s):  
Geise de Santana dos Anjos Zerfass ◽  
Dmitry A. Ruban ◽  
Farid Chemale Jr. ◽  
Henrique Zerfass

Abstract The Pelotas Basin, located on the SE Brazilian shelf, has evolved since the Aptian. Stratigraphical data from the basin can be used for delineation of the unconformity-bounded units (synthems) on the shelf, which is a first step towards a full understanding of its stratigraphic architecture, evolution, and hydrocarbon potential. Hiatuses in the Cenozoic succession of the Pelotas Basin are established with both biostratigraphic (planktonic foraminifers and calcareous nannofossils) and isotopic (87Sr/86Sr) data. The seven recognised hiatuses are dated respectively as (1) Palaeocene (Danian- Thanetian), (2) Palaeocene/Eocene boundary (Thanetian-Ypresian), (3) Eocene (Ypresian-Lutetian), (4) Eocene-Oligocene (Lutetian-Rupelian), (5) early-late Oligocene (Rupelian-Chattian), (6) early Miocene (Aquitanian-Burdigalian), and (7) middle-late Miocene (Serravallian-Tortonian). These intervals between the hiatuses are correlated with those of the Santos and Campos Basins north from the Pelotas Basin. The breaks in sedimentation that these basins have in common occurred (1) at the Palaeocene-Eocene and (2) Eocene-Oligocene transitions, (3) in the early Miocene, and (4) in the middle-late Miocene. These main unconformities outline five synthems on the SE Brazilian shelf, viz. the SEBS-1 (Palaeocene), SEBS-2 (Eocene), SEBS-3 (Oligocene), SEBS-4 (early-middle Miocene) and SEBS-5 (late Miocene-Holocene). The above unconformities are correlated with those established in the Cenozoic sedimentary successions of different regions such as Western Siberia, Arabia, NW and NE Africa, peninsular India, S Australia, the Gulf of Mexico, NW Europe, and South Africa. The only regional unconformity, near the Oligocene/Miocene boundary, coincides with the nearly-global sedimentation break. The latter was resulted from a climatic event, i.e., the ‘Mi-1 glaciation’. Thus, a eustatic origin is supposed for this regional unconformity. The other regional unconformities also correspond to global sea-level falls (probably with an exception for the Palaeocene/Eocene surface), which suggests that global eustatic movements controlled the development of the regional synthem architecture.


2012 ◽  
Vol 372 (1) ◽  
pp. 561-584 ◽  
Author(s):  
R. W. Harrison ◽  
E. Tsiolakis ◽  
B. D. Stone ◽  
A. Lord ◽  
J. P. McGeehin ◽  
...  

Crustaceana ◽  
2017 ◽  
Vol 90 (7-10) ◽  
pp. 953-967 ◽  
Author(s):  
Sebastian Klaus ◽  
Célio Magalhães ◽  
Rodolfo Salas-Gismondi ◽  
Martin Gross ◽  
Pierre-Olivier Antoine

We describe claw fragments of fossil primary freshwater crabs from three areas in the Amazon basin, Tarapoto (Early Oligocene) and Contamana (Middle Eocene to early Late Miocene) in Peru, and Eirunepé (Late Miocene) in Brazil. All these fragments most likely belong to the family Trichodactylidae. We show a continuous presence of primary freshwater crabs in proto-Amazonian lowlands from the Middle Eocene to the Late Miocene and can thus shift the earliest appearance date of freshwater-adapted brachyurans into the Eocene, at least in the Neotropics.


2019 ◽  
Vol 75 (2) ◽  
pp. 268-280 ◽  
Author(s):  
Ünal Akkemik ◽  
Nevriye Neslihan Acarca Bayam

Taxodioxylon Hartig, (emended by Gothan 1905) was widely described from the late Oligocene of the European part of Turkey (Thrace) and the early Miocene of greater Turkey, Anatolia.,C,. was also described from the early Miocene of central Anatolia. The purpose of this paper is to present a more detailed extended history of these two genera up to the late Miocene (Tortonian) with new descriptions from the Galatean Volcanic Province in central Turkey. The wood identification showed the presence of two fossil species;,D,et B,and,(G,.) G,. In conclusion, the swamp and lowland warm-temperate forest composition including,and,in the Galatean Volcanic Province, continued from the early Miocene (Burdigalian) to the late Miocene (Tortonian).


Author(s):  
Lars W. VAN DEN HOEK OSTENDE ◽  
Isaac CASANOVAS-VILAR ◽  
Marc FURIÓ

The Vallès-Penedès Basin in Catalonia (NE Spain) forms a biogeographically important connection between central Europe and the Iberian Peninsula. Whereas this is well documented for the late middle and early late Miocene, the early Miocene sequence has received far less attention. New excavations yielded micromammal assemblages from the Ramblian and early Aragonian. Among the euliphotyhplans and metatherian studied, we recognize seven non-soricid species (Amphiperatherium frequens von Meyer, 1846, Galerix symeonidisi Doukas, 1986 and Galerix remmerti van den Hoek Ostende, 2003, Desmanodon daamsi van den Hoek Ostende, 1997, Heterosorex neumayrianus Schlosser, 1887, Chainodus sp., Plesiodimylus sp.) and six species of shrews (Paenelimnoecus sp., Miosorex sp., cf. Clapasorex, cf. Oligosorex, cf. Florinia sp. and Soricinae indet.). They confirm the intermediate position of the Vallès-Penedès also at the time of the older faunas, but show that differences with the Iberian inland were less pronounced. These differences can be explained by higher humidity in the coastal region, as indicated by the presence of dimylids. The differences between this coastal area and inland basin confirm the potential of coastal regions as migration corridors.


2018 ◽  
Vol 92 (3) ◽  
pp. 506-522 ◽  
Author(s):  
Chiara Angelone ◽  
Stanislav Čermák ◽  
Blanca Moncunill-Solé ◽  
Josep Quintana ◽  
Caterinella Tuveri ◽  
...  

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


PalZ ◽  
2021 ◽  
Author(s):  
Beniamino Mecozzi ◽  
Alessio Iannucci ◽  
Fabio Bona ◽  
Ilaria Mazzini ◽  
Pierluigi Pieruccini ◽  
...  

AbstractA river otter hemimandible has been rediscovered during the revision of the historical collections of G.A. Blanc from Grotta Romanelli, complementing the ongoing multidisciplinary research fieldwork on the site. The specimen, recovered from the level G (“terre rosse”; early Late Pleistocene or late Middle Pleistocene), is here assigned to Lutra lutra. Indeed, morphological and morphometric comparisons with other Quaternary Lutrinae fossils from Europe allow to exclude an attribution to the relatively widespread and older Lutra simplicidens, characterized by distinctive carnassial proportions. Differences with Cyrnaonyx antiqua, which possessed a more robust, shellfish-feeding dentition, support the view of a successful niche repartition between the two species during the late Middle to Late Pleistocene of Europe. The occurrence of Lutra lutra from the “terre rosse” of Grotta Romanelli suggests deep modifications of the landscapes due to the ecological adaptation of the taxon, and indicates that the Eurasian otter spread into Europe at the Middle–Late Pleistocene transition.


2003 ◽  
Vol 13 (1) ◽  
pp. 41-66 ◽  
Author(s):  
Robert G. Bednarik

Archaeological data from Wallacea (Indonesia) and elsewhere are summarized to show that the history of seafaring begins in the Early Pleistocene, and that this human capability eventually led to Middle Palaeolithic ocean crossings in the general region of Australia. To understand better the technological magnitude of these many maritime accomplishments, a series of replicative experiments are described, and the theoretical conditions of these experiments are examined. The proposition is advanced that hominid cognitive and cultural evolution during the Middle and early Late Pleistocene have been severely misjudged. The navigational feats of Pleistocene seafarers confirm the cultural evidence of sophistication available from the study of palaeoart.With comments from Mike Morwood, Michael Rowland, Matthew Spriggs, Iain Davidson, Ursula Mania, and G.A. Clark and followed by a reply from the author.


2017 ◽  
Vol 4 ◽  
pp. 1-53 ◽  
Author(s):  
Paul Murphey ◽  
K.E. Townsend ◽  
Anthony Friscia ◽  
James Westgate ◽  
Emmett Evanoff ◽  
...  

The Bridger Formation is restricted to the Green River Basin in southwest Wyoming, and the Uinta and Duchesne River Formations are located in the Uinta Basin in Utah. These three rock units and their diverse fossil assemblages are of great scientific importance and historic interest to vertebrate paleontologists. Notably, they are also the stratotypes from oldest to youngest for the three middle Eocene North American Land Mammal Ages—the Bridgerian, Uintan, and Duchesnean. The fossils and sediments of these formations provide a critically important record of biotic, environmental, and climatic history spanning approximately 10 million years (49 to 39 Ma). This article provides a detailed field excursion through portions of the Green River and Uinta Basins that focuses on locations of geologic, paleontologic, and historical interest. In support of the field excursion, we also provide a review of current knowledge of these formations with emphasis on lithostratigraphy, biochronology, depositional, and paleoenvironmental history, and the history of scientific exploration.


Sign in / Sign up

Export Citation Format

Share Document