Zooarqueologia e tafonomia de Castanheiro do Vento

Dissertação mest., Arqueologia, Universidade do Algarve, 2007This dissertation is the result of the study of the faunal remains recovered until the 2006 field season, in the archaeological site of Castanheiro do Vento, located on the top a of a 700 m high hill, near Teja Valley in Horta do Douro, Vila Nova de Foz Côa. The site is characterized by a complex architectural system in schist dated to the III/II millennium b. C.. Due to the geomorphological setting, the sediments result from the degradation of the local schist (manipulated by humans). Besides a very slow sedimentation process, the faunal assemblage shows some specific characteristics such as a very low percentage of identifiable material and a very high index of fragmentation. According to these characteristics, our study began with a taphonomic approach, trying to reconstruct the different phenomena responsible by the perturbation of the original accumulations of bones. In the case of the assemblage recovered in Castanheiro do Vento, we could see that the cultural and erosion were the main agents responsible by the characteristics of bones. Being a site constructed and re-constructed by humans with the local materials like stone and clay, and located in a top of a hill with very low sedimentation process, the assemblage corresponds mainly to secondary accumulations though there is a very small percentage of the original accumulation at the site

Sobre alguns jaciments de Myotragus balearicus Bate 1980 (Artiodactyla, Caprinae) de tafonomia infreqüent

[cat] Presentam la descripció i interpretació tafonòmica d'una sèrie de jaciments menorquins i mallorquins de Myotragus balearicus. Es tracta de dipòsits situats a coves inaccessibles per a un caprí. Les restes trobades procedeixen del transport realitzat per ocells de presa de talla gran. El candidat més versemblant d'haver estat l’agent bioacumulador d'aquests dipòsits és l'àguila reial, Aquila chrysaetos.[eng] The description and taphonornical interpretation of several Mallorcan and Menorcan deposits containing Myotragus balearicus are presented in this paper. They are situated in- side inaccessible caves for a caprine animal. The studied fossils come from accumulations originated by large avian predators. The most plausible candidate as the bioaccumulator agent is the golden eagle, Aquila chrysaetos

Influência dos Fatores Ambientais na Preservação da Microfauna de Foraminíferos Bentônicos no Ambiente Recifal dos Parrachos de Maracajaú, RN, Brasil.

Taphonomy focuses on the post-mortem processes of transport and preservation of biotic remains in the sedimentaryrecord, and as such it has important applications for paleoenvironmental reconstructions. The aim of this work is to verifythe degree of dissolution, abrasion, bioerosion and fragmentation in foraminiferal tests recovered from bottom sedimentsof the Parrachos de Maracajaú, Rio Grande do Norte, and to estimate the influence of these taphonomic processes in thedistributon and preservation of the assemblages. Fifty-one species of benthic foraminifera have been found in the studiedsite. The taxonomic composition is typical of a coral reef environment. Amphistegina lessoni, Sorites marginalis, Quinqueloculinalamarckiana, Q. agglutinans, Peneroplis carinatus and Archaias angulatus are abundant in all the studiedlocalities. The energy of the environment was interpreted as high. The species have been grouped into two groups, andthe statistical data show that all four taphonomic processes (dissolution, abrasion, bioerosion and fragmentation) haveinfluenced the distribution and preservation patterns of the foraminifera

Bioestratigrafía, tafonomía y paleoecología

Se estudian las relaciones entre la Bioestratigrafía, la Tafonomía, la Paleoecología y las ciencias afines y asociadas, en un intento de clarificar conceptos básicos y de establecer un conjunto lógico y coherente

Bioestratigrafía, tafonomía y paleoecología

Se estudian las relaciones entre la Bioestratigrafía, la Tafonomía, la Paleoecología y las ciencias afines y asociadas, en un intento de clarificar conceptos básicos y de establecer un conjunto lógico y coherente

Phylloceratina ammonoids in the Iberian Basin during the Middle Jurassic: a model of biogeographical and taphonomic dispersal related to relative sea-level changes

Phylloceratina and Lytoceratina ammonoids in the Middle Jurassic of the Iberian Chain (E. Spain) represent less than 1% of the whole of Ammonoidea. There are two intervals, however, in which their occurrence is remarkably constant: within the Upper Bajocian and at the Lower/Middle Callovian boundary. These two dispersal episodes of Phylloceratina and Lytoceratina into the Iberian Basin are regarded to reflect changes in their palaeoecological and taphonomical behaviour, as a consequence of regional sea-level changes during the Middle Jurassic. A relative rise during the Late Bajocian favoured the immigration of juvenile phyllocerataceans. Phylloceras and Adabofoloceras immigrations gave rise to monospecific assemblages, where they soon died. They did not breed or ontogenically develop in this basin. In contrast, phyllocerataceans recorded at the Lower/Middle Callovian boundary constitute polyspecific assemblages, dominated by adult individuals. These Callovian assemblages were formed by nekroplanktonic drift, related to a relative sea-level fall and general homogenization of the shelf bottom, hence favouring the concentration of remains of organisms from more open marine and oceanic areas