http://hdl.handle.net/2122/228 Search the Channel search http://www.earth-prints.org/simple-search http://hdl.handle.net/2122/4130 Title: ‘‘Earliest Zanclean age for the Colombacci and uppermost Di Tetto formations of the « latest Messinian » northern Apennines: New palaeoenvironmental data from the Maccarone section (Marche Province, Italy)’’ by Popescu et al. (2007) Geobios 40 (359–373) <br/> <br/>Authors: Roveri, M.; Dipartimento di Scienze della Terra, Università di Parma, Via G.P. Usberti, 157/A, 43100 Parma, Italy; Bertini, A.; Dipartimento di Scienze della Terra, Università di Firenze, Via La Pira 4, 50121 Firenze, Italy; Cipollari, P.; Dipartimento di Scienze Geologiche, Università Roma-Tre, L.go S. Leonardo Murialdo 1, 00146 Roma, Italy; Cosentino, D.; Dipartimento di Scienze Geologiche, Università Roma-Tre, L.go S. Leonardo Murialdo 1, 00146 Roma, Italy; Di Stefano, A.; Dipartimento di Scienze Geologiche, Università di Catania, Corso Italia 55, 95129 Catania, Italy; Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Gennari, R.; Dipartimento di Scienze della Terra, Università di Parma, Via G.P. Usberti, 157/A, 43100 Parma, Italy; Gliozzi, E.; Dipartimento di Scienze Geologiche, Università Roma-Tre, L.go S. Leonardo Murialdo 1, 00146 Roma, Italy; Grossi, F.; Dipartimento di Scienze Geologiche, Università Roma-Tre, L.go S. Leonardo Murialdo 1, 00146 Roma, Italy; Iaccarino, S.; Dipartimento di Scienze della Terra, Università di Parma, Via G.P. Usberti, 157/A, 43100 Parma, Italy; Lugli, S.; Dipartimento di Scienze della Terra, Università di Modena e Reggio Emilia, Piazza S. Eufemia 19, 41100 Modena, Italy; Manzi, V.; Dipartimento di Scienze della Terra, Università di Parma, Via G.P. Usberti, 157/A, 43100 Parma, Italy <br/> <br/>Abstract: Two possible alternative interpretations of the claimed Zanclean age (Popescu et al., 2007) of two historical lithostratigraphic units of the Northern Apennines, usually referred to as Late Messinian in age and recording the so called Lagomare final event of the Messinian salinity crisis (MSC), are here discussed. The wrong age attribution of the Colombacci and "tetto" Fms. is ruled out based on data from the Maccarone and other sections showing that the Colombacci-Argille Azzurre Fm. boundary is basin wide synchronous and coincident with the Miocene-Pliocene boundary as far as it has been formally defined in the Eraclea Minoa GSSP. Alternatively, the opportunity of emending the Zanclean GSSP to a stratigraphically lower horizon recording the first evidence of marine influences in the Mediterranean following the MSC peak, seems not suitable, as (1) the marine signature of uppermost Messinian deposits is weak and still controversial and (2) no significant bio- and magnetostratigraphic events, well chronologically defined and recognizable at a global scale appear to be available to such a purpose. Mon, 29 Oct 2007 22:58:59 GMT http://hdl.handle.net/2122/4081 Title: Reply to Comment by M. Dumberry <br/> <br/>Authors: Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; De Michelis, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Piersanti, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Boschi, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione AC, Roma, Italia <br/> <br/>Abstract: We thank M. Dumberry for providing the opportunity to discuss further the article [Florindo et al., 2005] in which we suggested that the Sumatra earthquake could have triggered a geomagnetic jerk. Dumberry is against our hypothesis for different reasons: (1) The displacement pattern produced by this earthquake is incompatible with the core-mantle boundary (CMB) deformations required for a torsional oscillation; (2) most of the deformations occurred locally, producing an actual mass displacement that has not involved the entire Earth; and (3) no abrupt change in the length of day (LOD) has been observed after this event. Although we agree with some of the considerations proposed by Dumberry, we think that these do not rule out the possibility that a jerk has been triggered by the Sumatra earthquake or that in the future, other earthquakes could induce a change in the flow pattern near the CMB leading to a geomagnetic jerk. On the contrary, we retain that this hypothesis is plausible, although it is more correct to talk about the existence of a possible link between geomagnetic jerks and earthquakes where the earthquake magnitude is not the only discriminating parameter. Mon, 19 Sep 2005 22:58:59 GMT http://hdl.handle.net/2122/4080 Title: Variability in the vertical structure of the water column and paleoproductivity reconstruction in the central-western Mediterranean during the Late Pleistocene <br/> <br/>Authors: Incarbona, A.; Università degli Studi di Palermo, Dipartimento di Geologia e Geodesia, Via Archirafi 22, 90134 Palermo, Italy; Di Stefano, E.; Università degli Studi di Palermo, Dipartimento di Geologia e Geodesia, Via Archirafi 22, 90134 Palermo, Italy; Sprovieri, R.; Università degli Studi di Palermo, Dipartimento di Geologia e Geodesia, Via Archirafi 22, 90134 Palermo, Italy; Bonomo, S.; Università degli Studi di Palermo, Dipartimento di Geologia e Geodesia, Via Archirafi 22, 90134 Palermo, Italy; Censi, P.; Università degli Studi di Catania, Dipartimento di Scienze Geologiche, C.so Italia 155, 95129 Catania, Italy; Dinarès-Turell, J.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Spoto, S.; Università degli Studi di Catania, Dipartimento di Scienze Geologiche, C.so Italia 155, 95129 Catania, Italy <br/> <br/>Abstract: A sedimentary sequence spanning Marine Isotope Stage (MIS) 6 to MIS 2 in core LC07, recovered in the central Mediterranean, has been investigated in order to produce a high-resolution paleoceanographic reconstruction. The changes in productivity deduced from calcareous plankton relative abundances and independently confirmed by the BaXS fluctuations are linked to the stability of the water column which is mainly controlled by the water mass temperature. During glacial intervals, productivity was generally enhanced. Oligotrophic and warmer water masses with a deepened seasonal thermocline can be inferred for most of MIS5. The magnetic properties of the sediment show increased occurrences of North Africa dust in the central Mediterranean during cold phases, likely as a consequence of a more efficient erosive process triggered by southward displacement of the intertropical convergence zone. Although increases in both productivity and Saharan dust occurred during cold periods, the atmospheric inputs do not seem to contribute significantly to the fertilization of primary producers. A Shannon Index curve has been used to tentatively synthesize the variations of calcareous nannofossil assemblages through the last 150 kyr. The assemblage diversity sharply increased coincident with the transition from the penultimate glacial to the last interglacial, subsequently low diversity was gradually reached again in the last glacial. Fri, 29 Aug 2008 22:58:59 GMT http://hdl.handle.net/2122/4078 Title: Could the Mw = 9.3 Sumatra Earthquake Trigger a Geomagnetic Jerk? <br/> <br/>Authors: Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; De Michelis, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Piersanti, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Boschi, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione AC, Roma, Italia <br/> <br/>Abstract: The magnetic field observed at the Earth’s surface is not a stationary feature. It is characterized by time variations ranging from milliseconds (micropulsations) to millions of years (the time interval between field reversals). Time variations with periods of a year or longer are related to Earth’s outer core sources, whereas for shorter timescales an external origin is invoked (i.e., solar activity). One of the most interesting time variations of the geomagnetic field is represented by the “geomagnetic jerk.” It is idealized as a rapid change in the slope of the secular variation, defined as the first derivative of the geomagnetic field. This means that the secular variation roughly appears as a series of straightline segments separated by geomagnetic jerks. Mon, 21 Mar 2005 22:58:59 GMT