Search results for "ROCK"

Temple-complex post-dates tsunami deposits found in the ancient harbour basin of Ostia (Rome, Italy)

2015

Abstract Detailed geophysical and geoarchaeological investigations carried out in Ostia, ancient harbour of Rome, revealed two different generations of harbour basins and also proved the repeated impact of high-energy wave events on the study area. West of Ostia, at the southern bank of the Tiber, a lagoonal harbour existed from the 4th and 2nd cent. BC but was affected by strong siltation. At the same site, a river harbour was subsequently established from the 1st cent. AD onwards. Fluvial deposits of medieval age finally document Tiber river bank erosion affecting the abandoned site. Within the sedimentary record, distinct high-energy event deposits were found and seem to be related to ts…

Depositional model in subglacial cavities, Killiney Bay, Ireland. Interactions between sedimentation, deformation and glacial dynamics

2012

Subglacial meltwater drainage and sedimentary processes play a major role in ice-sheet dynamic but there is a lack of study of subglacial environment because modern ice-sheet beds remain inaccessible. Previous authors already intended to provide diagnostic criterion and recent investigations suggest that fluid pressure variations are a key factor in subglacial environment. This paper investigated the late Devensian sedimentary record in order to describe subglacial sedimentological facies associations and deformation features related to fluid overpressures. We used an integrated approach, based on stratigraphy, sedimentology and deformations styles to demonstrate a subglacial depositional m…

Neanderthal firewood management: Evidence from Stratigraphic Unit IV of Abric del Pastor (Eastern Iberia)

2015

This paper presents anthracological data from Abric del Pastor (Alcoi, Spain), a Middle Paleolithic rock shelter site. Analysis of 1077 wood charcoal remains from Stratigraphic Unit IV (S.U. IV), collected within archaeological combustion structures and from loose sediment outside of structures, allowed us to characterise the local landscape, as well as to approach the interaction between Neanderthal groups and their local environment. Taxonomic identification suggests that firewood was gathered from nearby sources, with predominance of juniper (Juniperus sp.) followed by thermophilous shrubby taxa. Additional analysis focussing on post-depositional processes affecting charcoal have shown f…

2017

Ranking among the largest volcanic eruptions of the Common Era (CE), the ‘Millennium Eruption’ of Changbaishan produced a widely-dispersed tephra layer (known as the B-Tm ash), which represents an important tie point for palaeoenvironmental studies in East Asia. Hitherto, there has been no consensus on its age, with estimates spanning at least the tenth century CE. Here, we identify the cosmogenic radiocarbon signal of 775 CE in a subfossil larch engulfed and killed by pyroclastic currents emplaced during the initial rhyolitic phase of the explosive eruption. Combined with glaciochemical evidence from Greenland, this enables us to date the eruption to late 946 CE. This secure date rules out…

New observations on a pottery fragment with incised deer from the Cova de l’Or (Beniarés, Alacant)

2007

The red external surface of a vessel, decorated with an incised group of deer from Cova de l’Or, has been long considered characteristic of the application of the almagra technique. However, the results of the elemental analysis of this fragment, compared with the results of another vessel with almagra decoration from the same site, call into question the application of this technique in the first vessel. In addition, searching for parallels for the schematic incised motifs of the vessel, in both ceramic decorations and rock art, we have concluded that rather than deer the represented animals are hinds.

Ceramic production at Selinunte (Sicily) during the 4th and 3rd century BCE: New archaeometric data through the analysis of kiln wastes

2018

Abstract A set of 37 overfired ceramic samples was collected from the dump of two kilns sited in the productive area FF1 in the acropolis of Selinunte (south western Sicily), being specifically active in the period 409–250 BCE. The ceramic samples were analysed by thin-section petrography and chemical analysis, with the aim to establish a valuable ‘reference group’ representative of the ceramic produced at Selinunte during the Punic phase. The petrographic and chemical analyses allowed to state that the ceramic manufactures from the kilns operating in the FF1 insula are characterized by rather homogeneous textural/compositional features. The daily-use common ware here produced is characteri…

Spectroscopic analysis used to uncover the original paint colour of the Helsinki Government Palace tower clock faces

2016

The paint stratigraphy of the two clock faces from the tower clock of the Government Palace in Helsinki (Finland) was analysed in order to determine their original colour before restoration works. Paint cross-section samples from both clock faces were analysed by confocal Raman microscopy and scanning electron microscopy coupled to an energy dispersive X-ray spectrometer (SEM-EDS). The results revealed the complex superimposition of paint layers applied over the original black colour. FTIR/ATR analyses proved that the original paint was prepared with linseed oil-resin media. Most likely not all of the different layer colours were visible. Some of the layers were likely to have been a primer…

Documenting carved stones from 3D models. Part II - Ambient occlusion to reveal carved parts.

2021

10 pages; International audience; Revealing carved parts in rock art is of primary importance and remains a major challenge for archaeological documentation. Computational geometry applied to 3D imaging provides a unique opportunity to document rock art. This study evaluates five algorithms and derivatives used to compute ambient occlusion and sky visibility on 3D models of Mongolian stelae, also known as deer stones. By contrast with the previous companion work, models are processed directly in 3D, without preliminary projection. Volumetric obscurance gives the best results for the identification of carved figures. The effects of model resolution and parameters specific to ambient occlusio…

A laboratory cave for the study of wall degradation in rock art caves : an implementation in the Vézère area

2013

The aim of this proposal is to present an original approach to the study and preservation of rock art caves. A multidisciplinary study of cave wall alteration will be performed to understand the impact of environmental context on the evolution of wall surfaces. The approach involves the choice of a cave with characteristics similar to painted caves in the studied area (Vézère Valley in Dordogne, France): e.g., cave wall alteration, lithology, morphology, etc. This selected cave is intended to become a laboratory cave, monitored for the acquisition of chemical, physical and biological environmental data on bedrock, air and fluids along with their characteristics. A cave without art or archae…

Terrestrial laser scanning and close range photogrammetry for 3D archaeological documentation: the Upper Palaeolithic Cave of Parpalló as a case study

2010

Graphic and metric archaeological documentation is an activity that requires the capture of information from different sources, accurate processing and comprehensive analysis. If monitoring of the state of conservation is required, this task has to be performed before intervention, during and after the completion of the works in a repetitive way. This paper presents the use of terrestrial laser scanning (TLS) in order to effectively produce, prior to intervention, accurate and high-resolution 3D models of a cave with engravings dating back to the Upper Palaeolithic era. The processing of the TLS data is discussed in detail in order to create digital surface models. The complexity of the cav…