The role of Late Pleistocene-Holocene tectono-sedimentary history on the origin of patches of savanna vegetation in the middle Madeira River, southwest of the Amazonian lowlands

AbstractPaleoseismological techniques have been used to investigate gravitational deformations at the Mortirolo Pass (Valtellina region, central Alps), in order to improve the knowledge on the activation mechanisms and the evolution of deep-seated gravitational slope movements. The deformation has been responsible for mass sliding towards the Valtellina depression through the activation of several-hundred-metre-long shear planes. Minor shear planes dipping towards the mountain played the role of antithetic structures. Four trenches were excavated across scarps representing the surficial expression of shear planes affecting the bedrock and Late Pleistocene-Holocene deposits. The excavations enabled to investigate the stratigraphy of Quaternary deposits and the geometry and kinematics of the shear planes affecting them. Radiocarbon analyses on organic material contained in sediments and paleosols enabled to define a succession of displacement events which occurred during the Late Pleistocene-Holocene. Collected data indicate the persistence of the activity until recent times (last movement related to 1810-1540 cal. BP). A sudden movement has been detected along one of the main shear surfaces (dipping towards the valley) with a vertical displacement of several metres. In contrast, numerous displacements (with lower vertical offset) have been detected along the antithetic shear planes. Different hypotheses have been proposed in the past to define the origin of huge gravitational movements (glacial retreat, uplift of the Alpine chain, fault activity). However, the Late Pleistocene cycles of glacial loading and unloading on the mountain slopes seem to be the most probable factors causing deep-seated gravitational movements in the investigated region. A recent dramatic landslide in an area adjacent to the investigated one (Mt. Zandila-Valpola) testifies to the paroxistic evolution of the large scale gravitational deformations. The densely inhabited Valtellina region is affected by a large number of gravitational structures similar to those of the Mortirolo area. In consideration of the possible effects of the paroxistic activation of these structures, detailed studies on the chronology and kinematics of the deformations through the application of paleoseismological techniques should therefore be encouraged.

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The role of environmental filters in Brazilian savanna vegetation dynamics

Forest Ecology and Management ◽

10.1016/j.foreco.2021.119645 ◽

2021 ◽

Vol 500 ◽

pp. 119645

Author(s):

Natielle Gomes Cordeiro ◽

Kelly Marianne Guimarães Pereira ◽

Marcela de Castro Nunes Santos Terra ◽

Eduarda Martiniano de Oliveira Silveira ◽

Ivy Mayara Sanches de Oliveira ◽

...

Keyword(s):

Vegetation Dynamics ◽

Brazilian Savanna ◽

Environmental Filters ◽

Savanna Vegetation

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The role of ostrich in shaping the landscape use patterns of humans and hyenas on the southern coast of South Africa during the late Pleistocene

Multispecies Archaeology ◽

10.4324/9781315707709-20 ◽

2018 ◽

pp. 333-346 ◽

Cited By ~ 1

Author(s):

Jamie Hodgkins ◽

Petrus le Roux ◽

Curtis W. Marean ◽

Kirsty Penkman ◽

Molly Crisp ◽

...

Keyword(s):

South Africa ◽

Late Pleistocene ◽

Southern Coast ◽

Use Patterns ◽

Landscape Use

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The role of a proto-Schelde River in the genesis of the southwestern Netherlands, inferred from the Quaternary successions and fossils in Moriaanshoofd Borehole (Zeeland, the Netherlands)

Netherlands Journal of Geosciences – Geologie en Mijnbouw ◽

10.1017/s0016774600000299 ◽

2013 ◽

Vol 92 (1) ◽

pp. 69-86 ◽

Cited By ~ 4

Author(s):

A.A. Slupik ◽

F.P. Wesselingh ◽

D.F. Mayhew ◽

A.C. Janse ◽

F.E. Dieleman ◽

...

Keyword(s):

The Netherlands ◽

Late Pleistocene ◽

Late Quaternary ◽

Source Region ◽

Fossil Material ◽

Mammal Faunas

AbstractWe investigated the Quaternary lithological succession and faunas in a borehole near Moriaanshoofd (Province of Zeeland, SW Netherlands), in order to improve our understanding of the depositional context of classical Gelasian mammal faunas from the region. The fossils mostly derive from the base of a fossil-rich interval between 31 m and 36.5 m below the surface, that was initially interpreted as a Middle or Late Pleistocene interglacial marine unit, but turned out to be a Late Quaternary fluvial unit with large amounts of reworked fossils and sediments. Eocene mollusc taxa pinpoint Flanders (Belgium) as the source region for this river. Within the base of this paleo-Schelde River fossil material of various stratigraphic provenance became incorporated.

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Megafaunal Butchering at Lubbock Lake, Texas: A Taphonomic Reanalysis

Quaternary Research ◽

10.1016/0033-5894(88)90026-9 ◽

1988 ◽

Vol 30 (2) ◽

pp. 221-231 ◽

Cited By ~ 26

Author(s):

Lee Ann Kreutzer

Keyword(s):

Human Behavior ◽

Late Pleistocene ◽

Meat Processing ◽

Faunal Remains ◽

Point Bar ◽

Feature Structure ◽

Bone Accumulation ◽

Rule Out

Five seasons of excavation in Feature Area 2-1 of the Lubbock Lake Landmark, Texas, exposed a megafaunal bone accumulation in sands and gravels deposited by a late Pleistocene meandering stream. Many bone specimens exhibit evidence of alteration, supporting interpretation of the feature as an in situ, secondary meat-processing area; the gravels are interpreted as the point bar of a meandering stream. Faunal remains lying stratigraphically above the point bar have been considered to form a separate, noncultural feature produced by stream flooding. However, rose diagrams and analysis of adjusted residuals demonstrate that a statistically significant amount of bone in each feature is aligned along axes of preferred orientation. Further, the orientation patterns and statistical analyses of both features exhibit the same trends, suggesting that the same processes affected both. Although the evidence does not rule out a role of human behavior, it does demonstrate that stream currents significantly influenced feature structure.

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The role of birds in Late Pleistocene Eurosiberian-Mediterranean boundary reconstructions in Western Europe

Quaternary International ◽

10.1016/j.quaint.2018.01.023 ◽

2018 ◽

Vol 481 ◽

pp. 113-122 ◽

Cited By ~ 2

Author(s):

Carmen Núñez-Lahuerta ◽

Julia Galán ◽

Víctor Sauqué ◽

Gloria Cuenca-Bescós

Keyword(s):

Late Pleistocene ◽

Western Europe

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La Désirade island (Guadeloupe, French West Indies): a key target for deciphering the role of reactivated tectonic structures in Lesser Antilles arc building

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.184.1-2.21 ◽

2013 ◽

Vol 184 (1-2) ◽

pp. 21-34 ◽

Cited By ~ 9

Author(s):

Jean-Marc Lardeaux ◽

Philippe Münch ◽

Michel Corsini ◽

Jean-Jacques Cornée ◽

Chrystèle Verati ◽

...

Keyword(s):

Late Pleistocene ◽

Late Cretaceous ◽

West Indies ◽

Early Pleistocene ◽

Lesser Antilles ◽

Tectonic Structures ◽

Vertical Movements ◽

Late Pliocene ◽

Lesser Antilles Arc

Abstract In this paper we present and discuss new investigations performed on both the magmatic basement and the sedimentary formations of La Désirade. We report structural and sedimentary evidences for several episodes of deformation and displacement occurring prior to the present day tectonics. The main faults, respectively N130 ± 10°, N040 ± 10° and N090 ± 10°, previously considered as marker of the current tectonic regime corresponds to reactivated tectonic structures developed first during late Cretaceous compression and second during Pliocene to early Pleistocene extension. We demonstrate also the importance of late Pliocene-early Pleistocene and middle-late Pleistocene vertical movements in this part of the Lesser Antilles fore-arc as well as the role of compressive tectonics in the over thickened character of the arc basement in the Guadeloupe archipelago.

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Sediment record from the Kamyshovoe Lake: history of vegetation during late Pleistocene – early Holocene (Kaliningrad District, Russia)

Baltica ◽

10.5200/baltica.2015.28.11 ◽

2015 ◽

Vol 28 (2) ◽

pp. 121-134 ◽

Cited By ~ 5

Author(s):

Olga Druzhinina ◽

Dmitry Subetto ◽

Miglė Stančikaitė ◽

Giedrė Vaikutienė ◽

Jury Kublitsky ◽

...

Keyword(s):

Late Pleistocene ◽

Early Holocene ◽

Sediment Record ◽

Environmental Regime ◽

Maximum Value ◽

History Of Vegetation ◽

Shrub Tundra ◽

History Of ◽

Pollen Records

Newly obtained pollen and diatom data from the Kamyshovoe Lake (germ. Dobauen, Vishtynets Highland, Baltic Uplands) controlled by radiocarbon dating allowed to reconstruct the history of local vegetation during late Pleistocene – early Holocene. Pollen records show the formation of birch-predominating forest at ca. 13.4 ka cal. BP and the flourishing of pine towards the second half of the chronozone since about 13.2 ka cal. BP. The transition to the Younger Dryas around 12.7 ka cal. BP led to the development of sparse shrub tundra with Juniperus and communities of steppe herbs. Amelioration of the environmental regime enabled birch and pine woods to spread during the second part of GS-1 event and the Preboreal. The late Preboreal time is marked by the appearance of Populus and an increase in the role of grasses in the vegetation cover, which can be correlated to similar open vegetation phases deduced from other pollen records in Europe (11.3–11.1 ka cal. BP). During the Boreal (since ca. 10.0 ka cal. BP) Corylus had its maximum value, Alnus, Tilia and Quercus appeared and spread while the birch-pine forests retreated.

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