http://hdl.handle.net/2122/133 Thu, 23 May 2013 18:04:31 GMT 2013-05-23T18:04:31Z http://hdl.handle.net/2122/8254 Title: Early Miocene volcanic activity and paleoenvironment conditions recorded in tephra layers of the AND-2A core (southern McMurdo Sound, Antarctica) Authors: Di Roberto, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia; Del Carlo, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia; Rocchi, S.; Dipartimento di Scienze della Terra, Università di Pisa, Pisa, Italy; Panter, K. S.; Department of Geology, Bowling Green State University, Bowling Green, OH, 43403, USA Abstract: The ANtarctic geological DRILLing program (ANDRILL) successfully recovered 1138.54 m of core from drillhole, AND-2A, in the Ross Sea sediments (Antarctica). The core is composed of terrigenous claystones, siltstones, sandstones, conglomerates, breccias, and diamictites with abundant volcanic material. In this work we present sedimentological, morphoscopic, petrographic, and geochemical data on pyroclasts recovered from core AND-2A, which provide insights on eruption styles, volcanic sources, and environments of deposition. One pyroclastic fall deposit, 12 resedimented volcaniclastic deposits and 14 volcanogenic sedimentary deposits record a history of intense explosive volcanic activity in southern Victoria Land during the Early Miocene. Tephra were ejected during Subplinian and Plinian eruptions fed by trachytic to rhyolitic magmas and during Strombolian to Hawaiian eruptions fed by basaltic to mugearitic magmas in submarine/subglacial to subaerial environments. The long-lived Mt. Morning eruptive centre, located c. 80 km south of the drillsite, was recognized as the probable volcanic source for these products on the basis of volcanological, geochemical, and age constraints. The study of tephra in the AND-2A core provides important paleoenvironment information by revealing that the deposition of primary and moderately reworked tephra occurred in a proglacial setting under generally open water marine conditions. Sat, 31 Dec 2011 23:00:00 GMT http://hdl.handle.net/2122/8254 2011-12-31T23:00:00Z http://hdl.handle.net/2122/8192 Title: Plio-Pliocene high-low latitude climate interplay: a Mediterranean point of view Authors: Colleoni, F.; Centro Euro-Mediterraneo sui Cambiamenti Climatici; Masina, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Negri, A.; Universita' Politecnica delle Marche; Marzocchi, A.; Centro Euro-Mediterraneo sui Cambiamenti Climatici Abstract: The high–low latitude climate interplay during the Plio–Pleistocene global cooling is not yet well understood. Insight on the Mediterranean region can provide some clues about past significant climate changes since the basin reflects the climate dynamics of both high-latitude and low-latitude regions, being connected to the North Atlantic and subjected to monsoon influence. Here we shade light on this connection problem by per- forming a spectral analysis on an Eastern Mediterranean stack of planktonic records spanning the last 5 Ma and by further comparing it to North Atlantic and Pacific deep- and surface-water records. Our main conclu- sion is that the Mediterranean detected the main global climate transitions over the last 5 Myr although sapropel depositions indicate that it remained influenced by the African summer monsoon during the whole interval. Our analysis reveals that until 2.2 Ma the Mediterranean planktonic record is driven by re- gional processes dominated by precession. The progressive emergence of the 41-kyr frequency in the Medi- terranean records around 2.8 Ma suggests that, since this date, the Mediterranean was more and more affected by the high-latitude climate dynamics forcing than by the low-latitude one. Moreover, during the ongoing Plio–Pleistocene cooling, the 41-kyr frequency signal in the Mediterranean records anticipated high-latitude deep-water response to the intensification of the Northern Hemisphere Glaciations (NHG) and lagged the signal in tropical latitudes. Finally, toward 1.2 Ma the results suggest that the progressive shift from the 41-kyr to the 100-kyr frequency was led by the northern high latitudes. Overall, our results confirm that the Mediterranean is an ideal site to study the interplay between high and low latitude climates. Tue, 31 Jan 2012 23:00:00 GMT http://hdl.handle.net/2122/8192 2012-01-31T23:00:00Z http://hdl.handle.net/2122/8162 Title: Neogene tectonic and climatic evolution of the Western Ross Sea, Antarctica — Chronology of events from the AND-1B drill hole Authors: Wilson, G. S.; Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand; Levy, R. H.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand; Naish, T. R.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand; Powell, R. D.; Department of Geology & Environmental Geosciences, Northern Illinois University, DeKalb, IL 60115, USA; Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Ohneiser, C.; Department of Geology, University of Otago, PO Box 56, Dunedin, New Zealand; Sagnotti, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Winter, D. M.; ANDRILL Science Management Office, Department of Geosciences, University of Nebraska-Lincoln, Lincoln, NE 68588‐0340, USA; Cody, R.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand; Henrys, S.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand; Ross, J.; New Mexico Institute of Mining & Technology, Earth & Environmental Sciences, Socorro, NM 87801, USA; Krissek, L.; Byrd Polar Research Centre, The Ohio State University, Columbus, OH 43210, USA; Niessen, F.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany; Pompillio, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia; Scherer, R.; Department of Geology & Environmental Geosciences, Northern Illinois University, DeKalb, IL 60115, USA; Alloway, B. V.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand; Barrett, P. J.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand; Brachfeld, S.; Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, USA; Browne, G.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand; Carter, L.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand; Cowan, E.; Department of Geology, Appalachian State University, Boone, NC 28608‐2067, USA; Crampton, J.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand; DeConto, R. M.; Department of Geosciences, University of Massachusetts, Amherst, MA 01003‐9297, USA; Dunbar, G.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand; Dunbar, N.; Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand; Dunbar, R.; Department of Environmental Earth System Sciences, School of Earth Sciences, Stanford University, Stanford, CA 94305, USA; von Eynatten, H.; Department of Sedimentology and Environmental Geology, Geoscience Center Göttingen (GZG), Goldschmidtstrasse 3, Göttingen, Germany; Gebhardt, C.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany; Giorgetti, G.; Dipartimento di Scienze della Terra, Universita di Sienna, Via Laterina 8, I-53100, Sienna, Italy; Graham, I.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand; Hannah, M.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand; Hansaraj, D.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand; Harwood, D. M.; ANDRILL Science Management Office, Department of Geosciences, University of Nebraska-Lincoln, Lincoln, NE 68588‐0340, USA; Hinnov, L.; Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218, USA; Jarrard, R. D.; Department of Geology and Geophysics, University of Utah, Salt Lake City, UT 84112, USA; Joseph, L.; Environmental Studies Program, Ursinus College, Collegeville, PA 19426, USA; Kominz, M.; Department of Geology, Western Michigan University, Kalamazoo, MI 49008, USA; Kuhn, G.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany; Kyle, P.; New Mexico Institute of Mining & Technology, Earth & Environmental Sciences, Socorro, NM 87801, USA; Läufer, A.; Federal Institute for Geosciences & Natural Resources, BGR, Stilleweg 2, D-30655 Hannover, Germany; McIntosh, W. C.; New Mexico Institute of Mining & Technology, Earth & Environmental Sciences, Socorro, NM 87801, USA; McKay, R.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand; Maffioli, P.; Università Milano-Bicocca, Dipartimento di Scienze Geologiche e Geotecnologie, Piazza della Scienza 4, I-20126 Milano, Italy; Magens, D.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany; Millan, C.; Byrd Polar Research Centre, The Ohio State University, Columbus, OH 43210, USA; Monien, D.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany; Morin, R.; US Geological Survey, Mail Stop 403, Denver Federal Center, Denver, CO 80225, USA; Paulsen, T.; Department of Geology, University of Wisconsin, Oshkosh, 800 WI 54901, USA; Persico, D.; Departimento di Scienze della Terra, Universita di Parma, Parco Aeres delle Scienze, 157 Parma, Italy; Pollard, D.; Earth and Environmental Systems Institute, 2217 Earth-Engineering Science Bldg, University Park, PA 16802, USA; Raine, J. I.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand; Riesselman, C.; Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand; Sandroni, S.; Dipartimento di Scienze della Terra, Universita di Sienna, Via Laterina 8, I-53100, Sienna, Italy; Schmitt, D.; Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand; Sjunneskog, C.; Antarctic Marine Geology Research Facility, Department of Geology, Florida State University, Tallahassee, FL 32306, USA; Strong, C. P.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand; Talarico, F.; Dipartimento di Scienze della Terra, Universita di Sienna, Via Laterina 8, I-53100, Sienna, Italy; Taviani, M.; CNR, ISMAR — Bologna, Via Gobetti 101, I-40129 Bologna, Italy; Villa, G.; Departimento di Scienze della Terra, Universita di Parma, Parco Aeres delle Scienze, 157 Parma, Italy; Vogel, S.; Department of Geology & Environmental Geosciences, Northern Illinois University, DeKalb, IL 60115, USA; Wilch, T.; Albion College, Department of Geology, Albion, MI 49224, USA; Williams, T.; Columbia University, Lamont-Doherty Earth Observatory, Palisades, NY 10964, USA; Wilson, T. J.; Byrd Polar Research Centre, The Ohio State University, Columbus, OH 43210, USA; Wise, S.; Antarctic Marine Geology Research Facility, Department of Geology, Florida State University, Tallahassee, FL 32306, USA Abstract: Stratigraphic drilling from the McMurdo Ice Shelf in the 2006/2007 austral summer recovered a 1284.87 m sedimentary succession from beneath the sea floor. Key age data for the core include magnetic polarity stratigraphy for the entire succession, diatom biostratigraphy for the upper 600 m and 40Ar/39Ar ages for in-situ volcanic deposits as well as reworked volcanic clasts. A vertical seismic profile for the drill hole allows correlation between the drill hole and a regional seismic network and inference of age constraint by correlation with well‐dated regional volcanic events through direct recognition of interlayered volcanic deposits as well as by inference from flexural loading of pre‐existing strata. The combined age model implies relatively rapid (1 m/2–5 ky) accumulation of sediment punctuated by hiatuses, which account for approximately 50% of the record. Three of the longer hiatuses coincide with basin‐wide seismic reflectors and, along with two thick volcanic intervals, they subdivide the succession into seven chronostratigraphic intervals with characteristic facies: 1. The base of the cored succession (1275–1220 mbsf) comprises middle Miocene volcaniclastic sandstone dated at approx 13.5 Ma by several reworked volcanic clasts; 2. A late-Miocene sub-polar orbitally controlled glacial–interglacial succession (1220–760 mbsf) bounded by two unconformities correlated with basin‐wide reflectors associated with early development of the terror rift; 3. A late Miocene volcanigenic succession (760–596 mbsf) terminating with a ~1 my hiatus at 596.35 mbsf which spans the Miocene–Pliocene boundary and is not recognised in regional seismic data; 4. An early Pliocene obliquity-controlled alternating diamictite and diatomite glacial–interglacial succession(590–440 mbsf), separated from; 5. A late Pliocene obliquity-controlled alternating diamictite and diatomite glacial–interglacial succession (440–150 mbsf) by a 750 ky unconformity interpreted to represent a major sequence boundary at other locations; 6. An early Pleistocene interbedded volcanic, diamictite and diatomite succession (150–80 mbsf), and; 7. A late Pleistocene glacigene succession (80–0 mbsf) comprising diamictite dominated sedimentary cycles deposited in a polar environment. Sun, 30 Sep 2012 22:00:00 GMT http://hdl.handle.net/2122/8162 2012-09-30T22:00:00Z http://hdl.handle.net/2122/7786 Title: Toward a radiometric ice clock: uranium ages of the Dome C ice core Authors: Aciego, S.; Institute of Geochemistry and Petrology, ETH Zurich, Switzerland; Bourdon, B.; Department of Geological Sciences, University of Michigan, Ann Arbor, MI, USA; Schwander, J.; Climate and Environmental Physics, Physics Institute, University of Bern, Switzerland; Baur, H.; Institute of Geochemistry and Petrology, ETH Zurich, Switzerland; Forieri, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia Abstract: Ice sheets and deep ice cores have yielded a wealth of paleoclimate information based on continuous dating methods while independent radiometric ages of ice have remained elusive. Here we demonstrate the application of (234U/238U) measurements to dating the EPICA Dome C ice core based on the accumulation of 234U in the ice matrix from recoil during 238U decay out of dust bound within the ice. Measured (234U/238U) activity ratios within the ice generally increase with depth while the surface areas of the dust grains are relatively constant. Using a newly designed device for measuring surface area for small samples, we were able to estimate reliably the recoil efficiency of nuclides from dust to ice. The resulting calculated radiometric ages range between 80 ka and 870 ka. Measured samples in the upper 3100 m fall on the previously published age-depth profile. Samples in the 3200–3255 m section show a marked change from 723–870 ka to 85 ka indicating homogenization of the deep ice prior to resetting of the (234U/238U) age in the basal layers. The mechanism for homogenization is likely enhanced lateral ice flow due to high basal melting and geothermal heat flux. Fri, 31 Dec 2010 23:00:00 GMT http://hdl.handle.net/2122/7786 2010-12-31T23:00:00Z http://hdl.handle.net/2122/7273 Title: Ice and Bedrock Characteristics Underneath Dome C (Antarctica) From Radio Echo Sounding Data Analysis Authors: Zirizzotti, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Cafarella, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Urbini, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia Abstract: The Radio Echo Sounding (RES) system is one of the most widely used active remote sensing techniques for polar ice sheet exploration, including bedrock morphology studies and subglacial lake investigations. Recently, bedrock characterization has been improved through the analysis of radar echo strength. The analysis of the RES signal amplitude has been used to highlight areas of high reflectivity variation, attributable to wet ice-bedrock interfaces. In a previous paper the authors described a method to distinguish a wet or dry bedrock-ice interface by analyzing RES data and introducing a linear model for internal ice absorption. In the following paper this subject is reconsidered in greater depth, taking into account important aspects not considered in the previous paper. In particular, a comparison between the ice absorption rate from RES measurements and from EPICA ice core conductivity data was proposed. Moreover, the signal amplitude contributions of internal ice layers and different kinds of rock interface were evaluated. Encouraged by these results, further data analysis produced a new version of the bedrock reflectivity variation map of the Dome C area. The map confirms a wide dispersion of wet/dry rock interfaces in the area studied, indicating the possibility of flowing water along both sides of the Concordia Trench. Sun, 31 Jul 2011 22:00:00 GMT http://hdl.handle.net/2122/7273 2011-07-31T22:00:00Z http://hdl.handle.net/2122/7105 Title: The impact of volcanic emissions on Etna’s snow cover Authors: Calabrese, S.; Università di Palermo, Dipartimento DiSTeM; Parello, F.; Università di Palermo, Dipartimento DiSTeM; D'Alessandro, W.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia; Aiuppa, A.; Università di Palermo, Dipartimento DiSTeM; Bagnato, E.; Università di Palermo, Dipartimento DiSTeM; Bellomo, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia; Brusca, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia; Liotta, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia Editors: Belviso, C.; Fiore, S.; Giannossi, L. Abstract: Volcanoes are one of the major natural sources of several trace elements to the atmosphere: They contribute to atmospheric pollution by increasing the amount of reactive and greenhouse gases and aerosols. In particular, Mt. Etna is considered to be, on long-term average, the major global atmospheric point source of many environmental harmful compounds. Their emission occurs either through continuous passive degassing from open-conduit activity or through sporadic paroxysmal eruptive activity, in the form of gases, aerosols or particulate. For several months during the year (generally December-May), the summit of Mt. Etna is under a thick blanket of snow. This huge reservoir of frozen water, interacting with the volcanic plume, accumulates a great quantity of volcanogenic elements during the winter. Samples of snow were collected at different distances from summit craters along an 8 km radial transects, in the 2006 and 2007 winters. Each snow sample was analyzed for 37 elements in the laboratory using IC, ICP-OES and ICP-MS techniques. The impact of volcanic emissions is clearly detectable considering the opposite trends of pH and TDS (total dissolved solid) measured in snow samples with increasing distance from their “source”. The pH values range from 1.7 on the rim of the summit craters up to 7.6 at a distance of about 8 km, and TDS ranges from diluted samples (few mg/l) at distal sites, up to extremely concentrated samples (500 - 3500 mg/l) close to the emission vents. The acidity in precipitation around the volcano depends mainly on the concentrations of volcanogenic acid forming ions (SO2, HCl and HF), as well as on concentrations of mainly geogenic alkaline species, which may eventually neutralize the acidity. Regarding metals concentrations, there are orders of magnitude of difference between the different sites with decreasing values from the crater’s rim up to the farthest sites (5-8 km from craters). In particular three groups of elements were extremely enriched (many orders of magnitude higher) at the summit craters with respect to the distal samples: Halogens (Br, Cl, F, I) and S ascribable to volcanic gas contribution; Al, Fe and Ti deriving from magmatic silicate particulate; and elements such as Se, Cu, As, Bi, Cd, Tl, Pb and Hg which are highly mobile in the high temperature volcanic environment. Mon, 19 Sep 2011 22:00:00 GMT http://hdl.handle.net/2122/7105 2011-09-19T22:00:00Z http://hdl.handle.net/2122/5998 Title: Installazione di un mini-sistema DAQ con idrofono su fondale marino in acque basse Authors: Guardato, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; Orazi, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; Caputo, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; Buonocunto, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia Wed, 31 Mar 2010 22:00:00 GMT http://hdl.handle.net/2122/5998 2010-03-31T22:00:00Z http://hdl.handle.net/2122/5842 Title: Marine climate change and environmental indicators from the Marine Core Service Authors: Coppini, Giovanni; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Lyubartsev, Vladyslav; Centro EuroMediterraneo per i Cambiamenti Climatici; Pinardi, Nadia; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Fratianni, Claudia; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Tonani, Marina; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Adani, Mario; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Oddo, Paolo; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Dobricic, Srdjan; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Marullo, Salvatore; ENEA; Loewe, Peter; BSH; Santoleri, Rosalia; CNR-ISAC; Colella, Simone; CNR-ISAC; Volpe, Gianluca; CNR-ISAC Editors: ENVIROINFO Abstract: In the framework of the Mediterranean Operational Oceanography Network (MOON, http://www.moon-oceanforecasting.eu) The Mediterranean Forecasting System (Pinardi et al., 2003) has started the design and development of services that include the routine production of environmental and climate indicators. A process of identifying user requirements has been started in collaboration with European Environment Agency and the indicators definition and implementation aim to take user requirements into account. The indicators are extensively used by EEA (EEA web page on indicators: http://themes.eea.europa.eu/indicators/). INGV has carried out an analysis on the possible improvements of existing indicators in use by EEA and on the development of new indicators based on Marine Core Services (MCS) products. The list of indicators includes: Temperature, Chlorophyll-a (from ocean colour), Ocean Currents and Transport, Salinity, Transparency, Sea Level, Sea Ice and Density. A critical analysis has been carried out to identify the relevance of the above-mentioned indicators for EU policies, their spatial and temporal coverage, their accuracy and their availability (Coppini et al., 2008). INGV in collaboration with CNR-ISAC are directly involved on the development of the indicators in the Mediterranean region and European Seas region the Temperature and Chlorophyll-a (Chl-a) products are the most suitable for an indicator development test phase. In particular the OO Chl-a product, deduced from satellite data, is able to contribute to the further development of the EEA Chl-a indicator on eutrohpication that is based on in-situ measurements (CSI023). For this indicator a development phase has been undertaken in 2008 and 2009 within the European Topic Center for Water (ETC-W) for EEA. The temperature indicators, developed with the support of MyOcean and Operational Oceanography community, consist of long time series (1870-Today) of SST anomaly able to describe ocean temperature increase due to climate change in the European Seas and on SST trends map of the last 25 years for the European Seas. These last two indicators have been included in the last 2008 EEA report on Impacts of Climate change in the European Seas (http://www.eea.europa.eu/publications/eea_report_2008_4). Moreover MFS re-analysis have been produced for the Mediterranean Sea and it consists of daily output of MFS-OPA hydrodinamic model (1/16 of degree horizontal resolution) that assimilates all available in situ and satellite observation for 1985 to 2007. This reanalysis product is used to detect temperature anomalies over the last 20 years in the coastal zone that could be related with environmental stresses. In addition to that we have also identified a Density indicator that appears relevant for the ecosystem health assessment in the coastal waters. Tue, 08 Sep 2009 22:00:00 GMT http://hdl.handle.net/2122/5842 2009-09-08T22:00:00Z http://hdl.handle.net/2122/5383 Title: Il contributo dei pozzi perforati dalla Regione Lombardia alla conoscenza del Pleistocene lombardo Authors: Scardia, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia; Muttoni, G.; Università di Milano Abstract: Facies analysis applied to several up to 220-m-deep cores, taken by Regione Lombardia in the central-northern Po Plain, allowed to recognize an overall regressive sequence consisting of cyclotemic shallow marine and fluvial-deltaic deposits overlain by distal to proximal braidplain sediments. Magnetostratigraphy, coupled with calcareous nannoplankton biostratigraphy, was used to date marine and fluvial-deltaic sediments to the early Pleistocene and continental sediments to the middle–late Pleistocene. Sediment accumulation rates were of ~0.3-0.4 mm/yr in the early Pleistocene, whereas an overall reduction in sediment accumulation rates to ~0.06-0.08 mm/yr, associated to relevant unconformities, characterized the middle-late Pleistocene. Stratigraphic evidences from petrographic, sedimentologic and palynologic analyses highlight in the Regione Lombardia cores a drastic reorganization of vegetational, fluvial, and Alpine drainage patterns, associated to a sequence boundary termed the “R surface”. The “R surface”, seismically traceable across the Po Plain subsurface, was constrained magnetostratigraphically to the first prominent Pleistocene glacio-eustatic lowstand of marine isotope stage (MIS) 22 at 0.87 Ma at the end of the Mid-Pleistocene Revolution, when climate worsened globally and locally caused the onset of the first major Pleistocene glaciation in the Alps. Most marine deposits in the cores lie above sea level highstands of corresponding age, suggesting that they have been uplifted. In order to estimate the observed rock uplift, sediments were back-stripped to elevations at times of deposition (expressed in meters above current sea level) by applying a simple Airy compensation model. The correlation of the isostatically corrected sedimentary facies to a glacio-eustatic reference curve obtained from classic oxygen isotope studies highlights a positive elevation mismatch (rock uplift) in the range of 70-120 m, which occurred after the onset of the major Pleistocene glacial-interglacial cycles at rates of at least 0.15-0.09 mm/yr. Although the driving forces of the observed rock uplift cannot be unambiguously identified, but its timing of onset after the beginning of the major Pleistocene glacial-interglacial cycles and the low seismicity observed in the most of the Regione Lombardia area seem to point to an isostatic readjustment of the chain probably due to the long-term erosional removal of sediments during major Pleistocene glacial advances. Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2122/5383 2008-12-31T23:00:00Z http://hdl.handle.net/2122/5382 Title: Late Matuyama climate forcing on sedimentation at the margin of the southern Alps (Italy) Authors: Scardia, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia; Donegana, M.; CNR-IDPA; Muttoni, G.; Università di Milano; Ravazzi, C.; CNR-IDPA; Vezzoli, G.; Università di Milano-Bicocca Abstract: The Pleistocene history of climate control on sedimentation in the Southern Alps-Po Plain system, northern Italy, was reconstructed using an integrated magnetostratigraphic, palynological, and petrographical approach on a 47-m-deep core. The core mainly consists of lacustrine sediments pertaining to the Bagaggera sequence, deposited at the foothills of the Southern Alps during the late Matuyama subchron (0.99–0.78 Ma). At that time, climate worsened globally and locally it caused the progradation of an alluvial fan unit onto the nearby Po Plain, triggering lake formation by damming of a tributary valley. These new data are used in conjunction with data from the literature to highlight and track the effects of climate forcing on sedimentation during the late Matuyama subchron in different orographic and geodynamic settings of the Southern Alps-Po Plain system as part of the greater Alpine area. We found that the episodes of alluvial fan and braidplain progradation observed in the southern foreland of the Alps during the late Matuyama global cooling seem broadly synchronous with the deposition of most of the so-called Günz and Älterer Deckenschotter deposits in the northern forelands of the Alps as well as with the first major waxing of the Alpine valley glaciers, possibly around the Marine Isotope Stage 22 (~0.87 Ma). Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2122/5382 2008-12-31T23:00:00Z