Search results for "Structural basin"

Potential implications of climate change and urbanization on watershed hydrology

2017

Abstract This paper proposes a modeling framework able to analyze the alterations in watershed hydrology induced by two recurrent drivers for hydrological changes: climate change and urbanization. The procedure is based on the coupling of a stochastic weather generator with a land use change model for the generation of some hypothetical scenarios. The generated scenarios are successively used to force a physically-based and spatial distributed hydrological model to reconstruct the basin response under different conditions. Several potential climate alterations are simulated by imposing negative and positive variations in the mean annual precipitation and a simultaneous temperature increase.…

Taken from the sea, reclaimed by the sea: The fate of the closed harbour of Elaia, the maritime satellite city of Pergamum (Turkey)

2013

Abstract During Hellenistic times, when the Pergamenian kingdom was prospering, Pergamum was operating an important harbour, used by merchants and military at the city of Elaia. This paper focuses on the development, utilisation and decay of the closed harbour of Elaia, which is discussed in the context of the landscape evolution of the environs of the ancient settlement. Based on geoarchaeological, archaeological and literary evidence, the construction of two harbour moles in order to provide shelter against wave action and enemies can be attributed to the early Hellenistic period. Geoelectric measurements revealed the construction profile of the moles. Coring evidence indicated that toget…

Geochemical characteristics of Cretaceous carbonatites from Angola

1999

Abstract The Early Cretaceous (138–130 Ma) carbonatites and associated alkaline rocks of Angola belong to the Parana-Angola-Etendeka Province and occur as ring complexes and other central-type intrusions along northeast trending tectonic lineaments, parallel to the trend of coeval Namibian alkaline complexes. Most of the Angolan carbonatite-alkaline bodies are located along the apical part of the Mocamedes Arch, a structure representing the African counterpart of the Ponta Grossa Arch in southern Brazil, where several alkaline-carbonatite complexes were also emplaced in the Early Cretaceous. Geochemical and isotopic (C, 0, Sr and Nd) characteristics determined for five carbonatitic occurren…

Gastropods from upper Pliensbachian–Toarcian (Lower Jurassic) sediments of Causses Basin, southern France and their recovery after the early Toarcian…

2015

AbstractA gastropod fauna has been studied from upper Pliensbachian – upper Toarcian deposits of two sections of the Causses Basin (southern France) in order to investigate the mode of recovery after the early Toarcian anoxic event. The fauna consists of 15 species, one of which is new (Bathrotomaria kronzwilmesorumsp. nov.). Their stratigraphical distribution shows two peaks of diversity – in the Bifrons Zone (Bifrons Subzone) and in the Aalensis Zone (Mactra Subzone) – which reflect brief times during which the oxygen content and bottom consistency favoured the settlement of a relatively diversified fauna. In the Variabilis–Pseudoradiosa zones, gastropods are only represented by two speci…

Late Aragonian mammal sites of Cuesta del Rey (Duero Basin, Burgos, Spain)

2017

[EN]: The Cuesta del Rey mammal sites located on the NE border of the Duero Basin are of great importance with regard to understand the general biostratigraphy of the basin, because Miocene mammal sites are extremely scarce in this area in comparison with the central part of the basin. The mammals identified in Cuesta del Rey-1 are: Eulipotyphla: cf. Miosorex sp.; Rodentia: Heteroxerus sp., Armantomys cf. tricristatus, Megacricetodon ibericus, Megacricetodon minor-Megacricetodon debruijni, Hispanomys sp. And Democricetodon sp. The Cuesta del Rey-1 rodent assemblage is characteristic of the end of the upper Aragonian (MN 7/8, end of the middle Miocene), equivalent to the local subzone G3 of …

Freshening of the Mediterranean Salt Giant: controversies and certainties around the terminal (Upper Gypsum and Lago-Mare) phases of the Messinian Sa…

2021

The late Miocene evolution of the Mediterranean Basin is characterized by major changes in connectivity, climate and tectonic activity resulting in unprecedented environmental and ecological disruptions. During the Messinian Salinity Crisis (MSC, 5.97-5.33 Ma) this culminated in most scenarios first in the precipitation of gypsum around the Mediterranean margins (Stage 1, 5.97-5.60 Ma) and subsequently > 2 km of halite on the basin floor, which formed the so-called Mediterranean Salt Giant (Stage 2, 5.60-5.55 Ma). The final MSC Stage 3, however, was characterized by a "low-salinity crisis", when a second calcium-sulfate unit (Upper Gypsum; substage 3.1, 5.55-5.42 Ma) showing (bio)geochemica…

Northern Hemisphere atmospheric pattern enhancing Eastern Mediterranean Transient-type events during the past 1000 years

2021

High-resolution climate model simulations for the last millennium were used to elucidate the main winter Northern Hemisphere atmospheric pattern during enhanced Eastern Mediterranean Transient (EMT-type) events, a situation in which an additional overturning cell is detected in the Mediterranean at the Aegean Sea. The differential upward heat flux between the Aegean Basin and the Gulf of Lion was taken as a proxy of EMT-type events and correlated with winter mean geopotential height at 500 mbar in the Northern Hemisphere (20–90∘ N and 100∘ W–80∘ E). Correlations revealed a pattern similar to the East Atlantic/Western Russian (EA/WR) mode as the main driver of EMT-type events, with the past …

Ages and stratigraphical architecture of late Miocene deposits in the Lorca Basin (Betics, SE Spain): New insights for the salinity crisis in margina…

2020

International audience; Unlike most Neogene basins of the Betic Cordillera where the Salinity Crisis is dated to the Messinian, a contradictory Tortonian dating was proposed for evaporites of the Lorca Basin. As a consequence, complex structural models have been proposed in the literature to explain this discrepancy in the timing of evaporites. In order to integrate the Lorca Basin into the geological context of the western Mediterranean domain during the Late Miocene, new sedimentological and stratigraphical studies coupled with new dating were performed, which allow us to propose a Messinian age for both diatomite-bearing deposits and evaporites of the Lorca Basin. These new ages challeng…

2018

Abstract. The 4.2 ka BP event is defined as a phase of environmental stress characterized by severe and prolonged drought of global extent. The event is recorded from the North Atlantic through Europe to Asia and has led scientists to evoke a 300-year global mega-drought. For the Mediterranean and the Near East, this abrupt climate episode radically altered precipitation, with an estimated 30 %–50 % drop in rainfall in the eastern basin. While many studies have highlighted similar trends in the northern Mediterranean (from Spain to Turkey and the northern Levant), data from northern Africa and the central-southern Levant are more nuanced, suggesting a weaker imprint of this climate shift on…

Neolithic rock art in context: Landscape history and the transition to agriculture in Mediterranean Spain

2008

Rock art is one of the most salient features of Neolithic societies in eastern Spain and an explicit form of landscape history. This paper summarizes current debates of Mediterranean rock art chronology and interpretation and explores the contextual differences in two areas of Neolithic settlement with rock art: the Canyoles Valley (Valencia) and the Alcoi Basin (Alicante). Large-scale survey of the Canyoles Valley resulted in a clearer understanding of agricultural land use during the Neolithic that contrasts with evidence from the Alcoi Basin. By analyzing Neolithic rock art in its archaeological context, we discuss the significance and limitations of rock art analysis for understanding a…