scholarly journals Vertebrate Palaeoecology of the Pisco Formation (Miocene, Peru): Glimpses into the Ancient Humboldt Current Ecosystem

2021 ◽  
Vol 9 (11) ◽  
pp. 1188
Author(s):  
Alberto Collareta ◽  
Olivier Lambert ◽  
Felix G. Marx ◽  
Christian de Muizon ◽  
Rafael Varas-Malca ◽  
...  
Keyword(s):  
Middle Miocene ◽  
Time History ◽  
Western Coast ◽  
Apex Predators ◽  
Humboldt Current ◽  
Deep Time ◽  
High Productivity ◽  
Pisco Formation ◽  
Bony Fishes ◽  
Vertebrate Assemblage

The northward-flowing Humboldt Current hosts perpetually high levels of productivity along the western coast of South America. Here, we aim to elucidate the deep-time history of this globally important ecosystem based on a detailed palaeoecological analysis of the exceptionally preserved middle–upper Miocene vertebrate assemblages of the Pisco Formation of the East Pisco Basin, southern Peru. We summarise observations on hundreds of fossil whales, dolphins, seals, seabirds, turtles, crocodiles, sharks, rays, and bony fishes to reconstruct ecological relationships in the wake of the Middle Miocene Climatic Optimum, and the marked cooling that followed it. The lowermost, middle Miocene Pisco sequence (P0) and its vertebrate assemblage testify to a warm, semi-enclosed, near-shore palaeoenvironment. During the first part of the Tortonian (P1), high productivity within a prominent upwelling system supported a diverse assemblage of mesopredators, at least some of which permanently resided in the Pisco embayment and used it as a nursery or breeding/calving area. Younger portions of the Pisco Formation (P2) reveal a more open setting, with wide-ranging species like rorquals increasingly dominating the vertebrate assemblage, but also local differences reflecting distance from the coast. Like today, these ancient precursors of the modern Humboldt Current Ecosystem were based on sardines, but notably differed from their present-day equivalent in being dominated by extremely large-bodied apex predators like Livyatan melvillei and Carcharocles megalodon.

Miocene start of modern carbonate platforms

Geology ◽  
2019 ◽  
Vol 47 (8) ◽  
pp. 771-775 ◽  
Author(s):  
Christian Betzler ◽  
Gregor P. Eberli
Keyword(s):  
Ocean Circulation ◽  
Deep Sea ◽  
Middle Miocene ◽  
Carbonate Platforms ◽  
Deep Time ◽  
Particle Sorting ◽  
Circulation Patterns ◽  
The World ◽  
Stacking Patterns ◽  
Extract Information

Abstract The middle Miocene onset of modern ocean circulation patterns changed the growth style of isolated tropical carbonate platforms because surface and contour currents began shaping the flanks of these edifices. Since then, ocean currents have redistributed the off-bank–transported sediment, reduced sedimentation by particle sorting or winnowing, and even eroded slopes. As a result, the flanks of isolated carbonate platforms around the world after 13–10 Ma have not only been constructed by mass gravity deposits, but equally by contourites with distinct drift and moat geometries. These produce specific stacking patterns of platform flank deposits. This flank architecture, produced by combined current and gravity processes, is typical of tropical carbonate platforms growing in the Neogene icehouse world. Comparison of this architecture with geometries in older platforms also has the potential to extract information about the rigor of ocean circulation in deep time where the deep-sea record is missing.

scholarly journals The cricetid rodents from Gratkorn (Austria, Styria): a benchmark locality for the continental Sarmatian sensu stricto (late Middle Miocene) in the Central Paratethys

2010 ◽  
Vol 61 (5) ◽  
pp. 419-436 ◽  
Author(s):  
Jérôme Prieto ◽  
Madelaine Böhme ◽  
Martin Gross
Keyword(s):  
Middle Miocene ◽  
Sensu Stricto ◽  
Long Distance ◽  
Central Paratethys ◽  
Terrestrial Vertebrate ◽  
Late Middle Miocene ◽  
Styrian Basin ◽  
Mammal Assemblages ◽  
Vertebrate Assemblage ◽  
Age Estimates

The cricetid rodents from Gratkorn (Austria, Styria): a benchmark locality for the continental Sarmatiansensu stricto(late Middle Miocene) in the Central ParatethysThe recent discovery of a terrestrial vertebrate assemblage in the clay pit St. Stefan at Gratkorn (Austria, Styrian Basin) is of major importance for our understanding of the evolution of late Middle Miocene mammal assemblages in the Paratethys realm. The cricetid rodent assemblage includes four species:Megacricetodon minutusDaxner, 1967,Democricetodonsp. nov. (sensuKälin & Engesser 2001),Eumyarionsp., and "Cricetodon" fandlisp. nov. The latter species belongs to the "Cricetodon" fandli-C. klariankaeHír, 2007 lineage, which allows for a long-distance correlation with other late Middle Miocene/earliest Late Miocene European localities. The biostratigraphic conclusions drawn from the study of the fossils from Gratkorn concurs with the age estimates based on regional geology, paleomagnetic measurements, and the gastropod-based biostratigraphy at the base of the Late Sarmatians. str.(late Serravallian, latest Volhynian), around 12-12.2 Ma (Chron C5An.1n) ago.

Towards a New Vision for Australian Politics

2021 ◽  
Author(s):  
Anne Tiernan
Keyword(s):  
Time History ◽  
Deep Time ◽  
European Settlement ◽  
Relative Success ◽  
Australian Continent ◽  
Political Studies ◽  
Political Traditions ◽  
History Of ◽  
Thematic Approach ◽  
New Vision

Australian politics is often characterized as derivative, pragmatic, and utilitarian—as insufficiently interesting or important to devote much time to. This Handbook challenges that contention, arguing it reflects a narrow, colonial perspective and ignores the richness and diversity of the deep-time history of the Australian continent and the unique inheritance the blending of Australia’s many histories and traditions has produced. Australian political studies encompasses a broad family of research disciplines, whose diverse and methodologically plural efforts have transformed our understanding of Aboriginal cultures and of European settlement. This volume’s thematic approach captures the politics, policies, and societies that have evolved in Australia’s many different landscapes and places. Its chapters present a theoretically rigorous, empirically informed, and historically nuanced account of what is distinctive about Australian politics, its capacity for democratic innovation and what accounts (its many shortcomings notwithstanding), for the resilience of its political traditions and Australia’s relative success.

Neogene Benthic Foraminiferal Biofacies, Paleobathymetry, and Paleoenvironments of a Gulf of Mexico Transect

2018 ◽  
Vol 48 (4) ◽  
pp. 356-372
Author(s):  
Miriam E. Katz ◽  
Kenneth G. Miller ◽  
Michael A. Kaminski ◽  
James V. Browning
Keyword(s):  
Gulf Of Mexico ◽  
Middle Miocene ◽  
Low Oxygen ◽  
High Productivity ◽  
Upper Miocene ◽  
Fault Tectonics ◽  
Lower Oxygen ◽  
Oxygen Conditions ◽  
Minimum Zone ◽  
Oxygen Minimum

Abstract We document Neogene benthic foraminiferal biofacies changes on a depth transect of six Gulf of Mexico industry wells (sidewall and cutting samples) that is oblique to the coast and extends from Main Pass to Green Canyon (offshore Alabama to Louisiana, USA). Calcareous nannofossil and planktonic foraminiferal biostratigraphic control provides the framework to make interwell comparisons of the benthic foraminiferal biofacies; these comparisons provide the basis for paleobathymetric and paleoenvironmental interpretations and to identify useful benthic foraminiferal biostratigraphic markers in this region. Benthic foraminiferal faunas indicate that Neogene paleodepths were slightly shallower at the eastern wells and deepened towards the western wells. Calcareous benthic foraminiferal biofacies dominated by Uvigerina spp. indicate that paleoenvironments characterized by low-oxygen conditions and/or high productivity occurred periodically during deposition along the transect. This is supported by repeated occurrences of a distinctive assemblage of agglutinated foraminifera (known as the “Agua Salada Fauna”) that is typical of dysaerobic environments. Evidence of intensified low-oxygen/high-productivity environments are recorded in lowermost Middle Miocene sediments at some locations and are present at all wells in Upper Miocene deposits. In Upper Miocene-Pliocene sediments, oxygen levels appear to have been related to paleodepth, indicating that the development of lower oxygen conditions was the result of an expansion or migration of the oxygen minimum zone. Our results are consistent with a global cause for the expansion of the oxygen minumum zone during the Late Miocene and widespread increase in export production. Our study shows that despite problems in well cuttings (cavings, inconsistent sampling) and complications in regional salt and fault tectonics, well transects can provide coherent benthic foraminiferal biofacies patterns that reveal paleobathymetric and paleoenvironmental changes in the Gulf of Mexico.

Early Cretaceous mealybug herbivory on a laurel highlights the deep‐time history of angiosperm–scale insect associations

2021 ◽  
Author(s):  
Lifang Xiao ◽  
Conrad C. Labandeira ◽  
Ben‐Dov Yair ◽  
S. Augusta Maccracken ◽  
Chungkun Shih ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
Time History ◽  
Scale Insect ◽  
Deep Time ◽  
History Of

scholarly journals 2000 Year-old Bogong moth (Agrotis infusa) Aboriginal food remains, Australia

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Birgitta Stephenson ◽  
◽  
Bruno David ◽  
Joanna Fresløv ◽  
Lee J. Arnold ◽  
...  
Keyword(s):  
Time History ◽  
Mountain Range ◽  
Dietary Practices ◽  
Archaeological Evidence ◽  
Deep Time ◽  
Language Groups ◽  
Australian Alps ◽  
The World ◽  
History Of ◽  
Aboriginal Groups

AbstractInsects form an important source of food for many people around the world, but little is known of the deep-time history of insect harvesting from the archaeological record. In Australia, early settler writings from the 1830s to mid-1800s reported congregations of Aboriginal groups from multiple clans and language groups taking advantage of the annual migration of Bogong moths (Agrotis infusa) in and near the Australian Alps, the continent’s highest mountain range. The moths were targeted as a food item for their large numbers and high fat contents. Within 30 years of initial colonial contact, however, the Bogong moth festivals had ceased until their recent revival. No reliable archaeological evidence of Bogong moth exploitation or processing has ever been discovered, signalling a major gap in the archaeological history of Aboriginal groups. Here we report on microscopic remains of ground and cooked Bogong moths on a recently excavated grindstone from Cloggs Cave, in the southern foothills of the Australian Alps. These findings represent the first conclusive archaeological evidence of insect foods in Australia, and, as far as we know, of their remains on stone artefacts in the world. They provide insights into the antiquity of important Aboriginal dietary practices that have until now remained archaeologically invisible.

scholarly journals Seismic Performance Evaluation of a Multistory RC Building in Padang City

2019 ◽  
Vol 258 ◽  
pp. 03018
Author(s):  
Jafril Tanjung ◽  
Maidiawati ◽  
Fajar Nugroho
Keyword(s):  
Ground Motion ◽  
Seismic Performance ◽  
Lateral Displacement ◽  
Time History ◽  
City Government ◽  
Dynamic Responses ◽  
Response Analysis ◽  
Western Coast ◽  
Rc Building ◽  
The City

Since a long time ago, Padang City has been recognized as one in most-earthquake and tsunami prone city in the world. The successive significant earthquakes that have struck western coast of Sumatra Island from 2004 to 2010 seems to warn the city about its prone condition. The last major Padang-Pariaman earthquake on September 30, 2009, for instance, has caused hundreds of death and lousy damage to thousands of houses and buildings in city. Recently, several new multistory reinforced concrete (RC) buildings have been established in this area. Its include such buildings as government office, mosques, hotels, school and university. The city government plans to use these buildings as vertical evacuation facilities if an earthquake followed by a tsunami hit the city in the near-future. As a consequence, of course, these infrastructures should be well designed and constructed to resist the future earthquakes motion. This paper discusses an evaluation of the seismic performance of an existing multistory RC building in Padang city. The building was a ten-story of hotel RC building located near the coastline of Padang city. A series Pushover and Time History Analyses were conducted to examine the seismic performance of the target R/C building. It uses STructural Earthquake Response Analysis (STERA-3D), a computer software based on the nonlinear finite element method. The Pushover analysis was conducted for maximum drift ratio 1/200 in X and Y directions, respectively. The input ground motion in a maximum acceleration of about 400 gals and 600 gals for 60 seconds’ excitation were used for the Time History Analysis. These input ground motions were generated from the recorded ground motion of 2009 Padang-Pariaman earthquake. The result of the analyses suggest that the current target multistory RC building has outstanding seismic performance. The result is based on the level of damage of the structural components, base shear, inter-story drift, lateral displacement, dynamic responses and the seismic capacity spectrum of the analytical model.

Herding the Cats of Deep Time

2018 ◽  
pp. 1-25
Author(s):  
David Wood
Keyword(s):  
Climate Change ◽  
Sexual Difference ◽  
Life Science ◽  
Time History ◽  
Uneven Development ◽  
Deep Time ◽  
The Past ◽  
Structural Inertia ◽  
Methodological Considerations ◽  
Philosophical Questions

This chapter aligns scientific and pre-philosophical angles on history with various reflective and methodological considerations. The past, a philosophical puzzle at the best of times, presents itself to us in many ways and at many different scales. If we abandon ideas of providence or progress for more naturalism we are left with numerous often incommensurable stories. And our inescapable performative interest we have in such accounts impacts our understanding of the present age and our arguably dark future. We draw here on phenomenological, hermeneutic, and deconstructive critique to articulate a provisional temporal phronesis by which to address the challenges of Deep Time. This brings to the fore such notions as irreversibility, fatal delay, structural inertia, uneven development, tipping points, time unimaginable, multiple strands, and aporetic time. Every age raises deep philosophical questions in its own way. War, freedom, justice, sexual difference have all had their day, but today the spectacle of anthropogenic climate change presses philosophy to the limit. Agency, responsibility, time, history, nature, earth, life, science, even truth—are not only live issues, they are becoming perspicuously mortal concerns. How to deal with the passions aroused by our situation, which both drive and block an adequate response to it?

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