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Abstract

The Efate Pumice Formation (EPF) is a trachydacitic volcaniclastic succession widespread in the central part of Efate Island and also present on Hat and Lelepa islands to the north. The volcanic succession has been inferred to result from a major, entirely subaqueous explosive event north of Efate Island. The accumulated pumice-rich units were previously interpreted to be subaqueous pyroclastic density current deposits on the basis of their bedding, componentry and stratigraphic characteristics. Here we suggest an alternative eruptive scenario for this widespread succession. The major part of the EPF is distributed in central Efate, where pumiceous pyroclastic rock units several hundred meters thick are found within fault scarp cliffs elevated about 800 m above sea level. The basal 200 m of the pumiceous succession is composed of massive to weakly bedded pumiceous lapilli units, each 2-3 m thick. This succession is interbedded with wavy, undulatory and dune bedded pumiceous ash and fine lapilli units with characteristics of co-ignimbrite surges and ground surges. The presence of the surge beds implies that the intervening units comprise a subaerial ignimbrite-dominated succession. There are no sedimentary indicators in the basal units examined that are consistent with water-supported transportation and/or deposition. The subaerial ignimbrite sequence of the EPF is overlain by a shallow marine volcaniclastic Rentanbau Tuffs. The EPF is topped by reef limestone, which presumably preserved the underlying EPF from erosion. We here propose that the EPF was formed by a combination of initial subaerial ignimbrite-forming eruptions, followed by caldera subsidence. The upper volcaniclastic successions in our model represent intra-caldera pumiceous volcaniclastic deposits accumulated in a shallow marine environment in the resultant caldera. The present day elevated position of the succession is a result of a combination of possible caldera resurgence and ongoing arc-related uplift in the region.

Neogene uplift and erosion in the Alpine Foreland Basin (Upper Austria and Salzburg)

In the present paper we apply a multi-technique approach (shale compaction data, seismic stratigraphy, isopach maps, moisture content of lignite, fission track data) to assess timing and amount of uplift and erosion of the Alpine Foreland Basin. The combination of the different techniques allows us to discriminate the effects of two different erosion events during the Neogene: (1) Seismic stratigraphy and isopach maps indicate a Karpatian (Early Miocene) regional tilting of the basin to the west (slope of about 0.5 %) and a minor erosion phase. (2) Moisture content of lignite combined with fission track data provides evidence for extensive regional uplift after deposition of Late Miocene fluvial deposits. It is estimated that sediments, 500 to 900 m thick, have been eroded. Shale compaction data derived from sonic logs indicates additional uplift of the eastern part of the basin (near the river Enns). Here, 300 to 1000 m of sediments were additionally eroded (giving a total erosion of about 1000 to 1900 m!), with a general increase of erosion thickness towards the northeast. While the regional uplift is probably related to isostatic rebound of the Alps after termination of thrusting, the local uplift in the east could be affected by Late Neogene E-W compressional events within the Alpine-Pannonian system. Both, tilting and erosion influence the hydrocarbon habitat in the Molasse Basin (tilting of oil-water contacts, PVT conditions, biodegradation).

Abstract

The Minjiang River terrace along the Longmen Shan fault zone near Wenchuan, at the eastern margin of the Tibetan Plateau, China, provides archives for tectonic activity and quaternary climate change. However, previous studies were not able to provide ages older than 100 ka due to the limitations of dating material or/and methods applied to date the fluvial sediments. In this study, we used the ESR signal of the Ti-Li center in quartz to obtain the ages of four higher terraces (T3–T6). According to the results, the terraces T3 to T6 were formed at 64±19 ka, 101±15 ka, 153±33 ka, and 423±115 ka, respectively. Combined with previous studies, these results indicate that the formations of all terraces correspond to glacial/interglacial transition periods, such as, T1-T5 being correlated to MIS2/1, MIS4/3, MIS5d/5c, and MIS6/5e respectively, while T6 probably to MIS12/11. According to these data, it is found that the average incision rate was significantly higher over the last 150 ka than that previous 100 ka (250 to 150 ka). As both tectonics and climate have affected the formation of these terraces, in addition to the overall uplifting of Tibetan Plateau, the regional uplift due to isostasy would be an additional tectonic factor in the formation of river terraces in the eastern margin of Tibetan plateau.

Abstract

The most recent research studies into the long-term landscape evolution of the Abruzzo area, carried out over the last twenty years at the “G. d’Annunzio” University of Chieti-Pescara, are based on an integrated approach incorporating structural geology and geomorphology and, in particular, the geomorphometry of topographic and hydrographic aspects, geological and structural-geomorphological surveys and mapping supported by morpho-stratigraphic and chronological constraints. The geomorphological analyses have allowed us to outline the main stages of geomorphological evolution and to identify the factors that have contributed to the landscape shaping of the Apennine Chain, the Adriatic Piedmont and the fluvial plains and coastal sectors, up to the Tremiti islands. In the Apennine Chain, landscape evolution — in a ridge, valley and basin system — is connected to the regional uplift, local tectonic subsidence and local base level variations, which have led to changes in the drainage systems, from exoreic to endorheic (in the intermontane basins) and then to exoreic again. In the Adriatic Piedmont, landscape shaping is connected to uplifting and eustatic sea-level fluctuations, which have induced the formation of a structure-controlled drainage system and the shaping of systems of entrenched alluvial fans and large consequent river valleys, with flights of river terraces. In the coastal Adriatic area — composed of a coastal plain-coastal slope system (northern and southern coast) and of a cliffed rocky coast (central coast, Tremiti) interrupted by river valleys — landscape shaping is the result of selective erosion due to the interaction between marine geomorphic processes and slope processes connected to Late Quaternary eustatic fluctuations.

(clays and sand with boulders) Tertiary and Quaternary deposits. The main source of sulphur in the landscapes under investigation are corbonaceous Cretaceous formations and Tertiary clayey formations. Sulphur occurs there according to oxygen-reduction conditions in the form of sulphates or sulphides. Sulphateous sulphur compounds (gyp- sum) are mainly found in deposits, building new regionally uplifted 80 BOGUMIE. WICIK forms of the surface (horsts and suspended wings of faults), that is in the positions conducive to oxidation. In the immediate vicinity of bor

., 2005b: Regional uplift and consequent gravitational phenomena: the example of eastern slope of Mt. Etna volcano. (Sollevamenti a grande scala e conseguenti fenomeni gravitativi: l'esempio del versante orientale dell'Etna [Sicilia]), Il Quaternario, 18 , 2, 157-171. Carveni P., Benfatto S., Salleo Puntillo M., 2007: Eastern Sicily uplift and some seismic and volcanic implications. (Il sollevamento della Sicilia orientale e salcune implicazioni sismiche e vulcaniche). Il Quaternario, 20 , 1, 57-66. Castorina G., 1920: Codavolpe earthquake [1920, September 26 th

). Calamita F., Coltorti M., Pieruccini P. & Pizzi A. 1999: Structural evolution and plio-quaternary morphogenesis of the Umbria-Marche Apennine. Boll. Soc. Geol. Ital. 118, 125–139 (in Italian). Calamita F., Satolli S. & Turtù A. 2012: Analysis of thrusts shear zones in curved shaped belts: Ddeformation mode and timing of the Olevano-Antrodoco-Sibillini thrust (Central-Northern Apennines of Italy). J. Struct. Geol. 44, 179–187. Cantalamessa G. & Di Celma C. 2004: Sequence response to syndepositional regional uplift: insights from high-resolution sequence stratigraphy

., Slipper I. & Walsh P., 1996. A palaeokarst of probable Kainozoic age preserved in Cambrian marble at Cemaes Bay, Anglesey, North Wales. Zeitschrift für Geomorphologie N. F., 40: 47-70. Nadin P.A., Kusznir N.J. & Toth J., 1995. Transient regional uplift in the Early Tertiary of the northern North Sea and the development of the Iceland Plume. Journal of the Geological Society , London, 152: 953-958. Newsome D. & Dowling R., 2005. The scope and nature of geotourism. In: Dowling R.K. & Newsome D. (eds.), Geotourism . Butterworth-Heinemann, Oxford: 3-25. Ollier C

–plèistocènes du Dètroit de Messine. Doc. et Trav. IGAL 11 97 99 Cucci L. 2004: Raised marine terraces in the Northern Calabrian arc (Southern Italy): a 600 kyr-long geological record of regional uplift. Annals of Geophysics 47, 4, 1391–1406. Cucci L. 2004 Raised marine terraces in the Northern Calabrian arc (Southern Italy): a 600 kyr-long geological record of regional uplift Annals of Geophysics 47 4 1391 1406 De Astis G., Ventura G. & Vilardo G. 2003: Geodynamic significance of the Aeolian volcanism (Southern Tyrrhenian Sea, Italy) in light of structural, seismological and

day with something else. It might be a bit more than a day, actually, if you think about preparing for it first of all, and then your initial discussion with patients, the letters and the initial discussion. So, more than a day, I’d say.” [HNS6] Based on the 2017/18 pay rate for a Band 7 haemophilia nurse in the UK (£31,696 to £41,787 basic national salary without regionaluplifts’ and additional employer costs), and assuming an additional workload associated with this product switch of one to three days, the nursing cost alone would be in the region of £365 to