Search results for " Tephra"
showing 5 items of 5 documents
Holocene hydrological changes in south-western mediterranean as recorded by lake-level fluctuations at lago Preola, a coastal lake in southern Sicily…
2011
This paper presents a high-resolution lake-level record for the Holocene at Lago Preola (Sicily, southern Italy) based on a specific sedimentological approach, with a chronology derived from AMS radiocarbon dates. It gives evidence of three major successive palaeohydrological periods, with (1) a pronounced dryness during the early Holocene until ca 10300 cal BP, (2) a highstand from ca 10300 to 4500 cal BP, and (3) a marked lowstand from 4500 cal BP to present. Large amplitude lake-level fluctuations characterise two transition phases at ca 10300e9000 and 6400e4500 cal BP. Period 2 was interrupted between 8300 and 7000 cal BP by a dry phase that was punctuated to ca 7300 cal BP by the depos…
PETROLOGICAL AND EXPERIMENTAL CONSTRAINTS OF THE PRE-ERUPTIVE CONDITIONS OF LA SOMMATA BASALT AND BROWN TUFFS TEPHRA (AEOLIAN ISLANDS)
2011
The principal focus of this thesis was the reconstruction of pre-eruptive conditions of two key eruptions at Vulcano island, the Brown Tuffs and the La Sommata, by combining the melt inclusion approach with phase equilibria derived by crystallization experiments. Brown Tuffs (the most energetic and widely distributed eruption of the Archipelago) were produced by several eruptions that occurred in a large age interval, 78-7.7 ka B.P. At Vulcano BT deposits crop out as proximal facies. La Sommata centre (age ca. 50 ka B.P.), is instead a basaltic scoria cone fed by one of the most primitive magmas of Aeolian Arc with ankaramitic affinity. Pyroxene-hosted melt inclusions on Lower and Intermedi…
Core description collected during Oceanographic Survey NextData2013 (12 – 19 September 2013)
2013
Final Report of the Oceanographic Survey NextData201. Project NEXTDATA WP-1.5 : Paleoclimatic Data from Marine Sediments
2013
The retrieval of series of proxy data on the past climate will serve to acquire a deeper understanding of the climate system and a more accurate prediction of its future development, as a priority task for the scientific community. In particular, the analysis of climate data of the past is an essential tool for studying the dynamics of the earth's climatic system in conditions different from present ones, and irreplaceable for testing the validity of medium- and long-term forecasting models. The determination of the influence of anthropogenic impacts on the planet’s environment is predicated on a clear understanding of the natural ways in which the earth's climate responds to the complex se…