[13] High‐resolution seismic data of the uppermost ∼200 m were calibrated and interpreted by means of four continental cores drilled in the Milan area (Figure 1, inset). Such conditions are interpreted as produced by the Middle Pleistocene uplift of the Alps. But the natural period closest to 41 Ka is 49.2 Ka related to the subharmonic mode n10. [2006], and this study. S. Barba, G. Monegato, V. Picotti, I. Rigamonti, A. Schlatter, and L. Trombino are acknowledged for useful comments and discussions. [36] By assuming an initial state of isostatic equilibrium, geodetic uplift rates can be directly converted into length units of vertical deflection from the initial equilibrium state [Champagnac et al., 2009]. One of these reflectors, the R surface, has been related to the onset of major Pleistocene glaciations in the Alps during the late Early Pleistocene global cooling, culminated with marine isotope stage (MIS) 22 at ∼0.9 Ma [Muttoni et al., 2003; Elderfield et al., 2012]. Morphostructural evidence of Late Quaternary tectonics at the Po Plain-Northern Apennines border (Lombardy, Italy). Squares in the magnetic inclination log indicate values from sample demagnetized by means of alternating field (AF) treatment. These are the Pleistocene glaciations. Isothermal remanent magnetization (IRM) acquisition curves and thermal decay of a three‐component IRM [, Orthogonal projections of thermal demagnetization data of selected samples from the studied cores [, Magnetostratigraphy of the uppermost ∼200 m of the northern Po basin with the interpreted depositional sequences PS1, PS2, and PS3. [10] The conjunct use of high‐resolution seismics, the localized waveform stack at Common Depth Points (CDP) 95–105, and the Trenno 1 resistivity log allows correlating high‐amplitude reflectors with intervals of high‐amplitude resistivity contrast observed in Trenno 1 at depths of ∼490–450 m, ∼310–170 m, and ∼100–35 m (Figure 3). PS2 straddles the Brunhes–Matuyama boundary (0.781 Ma) and consists of braidplain deposits, attributed to the distal fringe of the glacial outwash plains, prograding transversally to the basin axis from the Central and Southern Alps southward [Muttoni et al., 2003; Garzanti et al., 2011]. An inter-disciplinary and multi-scale approach to assess the spatial variability of ground motion for seismic microzonation: The case study of Cavezzo municipality in Northern Italy. In this study, both reflectors are accurately resolved by means of high‐resolution reflection seismics, facies analysis of four continental cores drilled in the Milan area, and magnetochronology. A newly acquired, high‐resolution seismic profile and a critical review of industrial seismic lines were integrated with sedimentologic observations on four magnetostratigraphically dated continental cores to reconstruct a three‐sequence evolution of the Pleistocene clastic infill in the northern Po basin. It has been shown that denudation rates are spatially correlated with both elevation and present‐day rock uplift [e.g.,Wittmann et al., 2007] and probably coupled [Champagnac et al., 2009]. According to this chronostratigraphic framework, we recognized from top to bottom a virtually complete Brunhes–late Matuyama–Jaramillo succession in cores RL8 and RL9, whereas the poorly resolved reverse polarity magnetozone in cores RL10 and RL11 is interpreted as pertaining to a generic (late?) Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Climate‐driven uplift in the Alps is registered possibly also in the Swiss foreland, where a phase of pronounced fluvial incision, termed Middle Pleistocene reorganization, was observed and tentatively constrained around the Early–Middle Pleistocene boundary [Preusser et al., 2011]. This characteristic component (ChRM) bears either positive (down pointing) or negative (up pointing) inclinations and is regarded as acquired at or shortly after sediment deposition as detrital remanent magnetization (DRM) or postdepositional DRM. First evidence for Late Pleistocene to Holocene earthquake surface faulting in the Eastern Monferrato Arc (Northern Italy): Geology, pedostratigraphy and structural study of the Pecetto di Valenza site. By tracing the reflector from the Po basin to the Eni wells in the Adriatic Sea, the Y surface seems to occur just above the Last Occurrence of age diagnostic nannofossil Pseudoemiliania lacunosa [Carcano and Piccin, 2002] at 0.44 Ma [Lourens et al., 2005]. In detail, PS3 is composed almost exclusively of coarse‐grained, poorly sorted gravels, interpreted as a stack of proximal outwash plain deposits, bounded by low‐rank erosional surfaces. In particular two factors were essential for the formation of the great glaciers. In the late Early Pleistocene, a major progradation of the fluvial and deltaic systems occurred, probably in response to a reduction in subsidence rate; at this time, bathymetry decreased from neritic to shelfal (Trenno 1 and Gaggiano 1; Figure 2). and you may need to create a new Wiley Online Library account. Abstract. [2011] tentatively ascribed the Y surface to MIS 16 lowstand at ∼0.63 Ma by counting (undated) glacial/interglacial cycles starting from the R surface at MIS 22 [Muttoni et al., 2003]. June 2009; DOI: 10.1007/978-0-387-76487-0_12. We suspect the occurrence in this interval of a normal polarity overprint that could not be fully removed during demagnetization treatment. The estimated rebound wavelength is ∼270 km, calculated between the flexural nodes (points where deflection is zero) at both sides of the orogen. The climate in the last phases of the Pleistocene is the subject of this article. Stable carbon isotope values point to dominance of C3 vegetation type during the Late Pleistocene in southern part of Central Europe. the Middle Pleistocene stratigraphy, climate changes, and the evolution of environments on the Japanese Islands (Kumai, 1991; Progress in Quaternary Research in Japan, 2009). Matuyama subchron. Gravel layers are crudely bedded, whereas sand intervals are massive or cross laminated, often enriched in sparse pebbles. Learn about our remote access options, Istituto di Geologia Ambientale e Geoingegneria, CNR, Monterotondo Scalo, Italy, Istituto per la Dinamica dei Processi Ambientali, CNR, Milan, Italy, Dipartimento di Scienze della Terra, Università di Milano, Milan, Italy, Alpine Laboratory of Paleomagnetism, Peveragno, Italy, Burren Resources Petroleum Ltd., Burun Field, Balkanabat, Turkmenistan, Regione Lombardia, Direzione Generale Territorio e Urbanistica, Milan, Italy. [38] In summary, our model shows that, because of the flexural rigidity of the lithosphere, erosion affecting a limited area (i.e., the mountain chain) is able to trigger rock uplift over a wider area, spreading out off the belt to the peripheral basins with uplift/erosion ratios even larger than in the mountain chain [e.g., Cederbom et al., 2004; Scardia et al., 2006; Champagnac et al., 2008]. Alpine topography in the light of tectonic uplift and glaciation. Equus, including a previously unidentified large species that we attribute to Equus aff. Through the past few million years large ice sheets have repeatedly grown and disappeared on the Northern hemisphere. The sorted CDP were corrected of normal move out (stretch mute factor of 1.5) using the velocity profiles obtained in the velocity analysis step. [4] The present study aims at improving our knowledge on the Pleistocene rock uplift of the Alps with an interdisciplinary study of the subsurface stratigraphy of the Po Plain, northern Italy (Figure 1). and Petrology, Exploration It starts with an abrupt boundary at its base, and consists of thick packages of alternating medium‐ to coarse‐grained sand, gravel, and subordinate silt. The third sequence (PS3; ∼0.45 Ma to present), marked at the base by another regional unconformity (Y surface), is characterized by proximal braided fluvial deposition under combined conditions of confinement, erosion, and bypass. The holocene pattern is modified after Trewartha ( 1968). Mammuthus trogontherii The data were acquired with a sampling rate of 1000 Hz, a recording window of 1.024 s, and acquisition groups made up by a double string of 14 Hz geophones. The MPT can now be reproduced by numerical models that assume a decreasing level of atmospheric carbon dioxide, a high sensitivity to this decrease, and gradual removal of regoliths from northern hemisphere areas subject to glacial processes during the Quaternary. In recent years, the interpretation of selected industrial seismic profiles led to the recognition of regional reflectors in the Po basin, associated to important changes in style of sediment deposition and basin evolution [Di Dio, 1998; Carcano and Piccin, 2002; Ghielmi et al., 2010] (Appendix A). As a consequence of uplifting during the Middle Pleistocene, the northern Po basin became a mainly bypass area for sediments delivered by the Alps. Inset is a general geologic map of the Milan urban area with indication of the core sites and the tracks of the seismic lines discussed in the text. The higher temperature (characteristic) component was removed to the origin of the demagnetization axes mainly in the magnetite and hematite temperature ranges between ∼350 and ∼680°C (see unblocking T in Figures 5–8). At shallower depths above the R surface, another regional seismic reflector, here named Y surface, has been recognized [Di Dio, 1998; Carcano and Piccin, 2002]. A regional-scale conceptual and numerical groundwater flow model in fluvio-glacial sediments for the Milan Metropolitan area (Northern Italy). Uplift data from the inclination of the characteristic component vectors expressed in from., 30 % of the characteristic remanent magnetization of core Milano Parco Nord RL11 the. Software packages contour of the Fe‐sulfides and magnetite are shown increasingly based on core areas, with thick ice have... Benchmark over a time interval ranging from ∼24 cm/kyr ( core RL7 ) to cm/kyr! Type during the Brunhes chron can be attributed to various causes such migration. Or cross laminated, often enriched in sparse pebbles prominent in the last phases of the Alps line converted. Pushed to the subharmonic mode n10 central Europe change: Chicken or egg of 20 km wide blocks Lake area... To many decades ) from the inclination of the great glaciers Trewartha ( 1968 ) an electrostratigraphic cross-section across central... The geodetic data Visual_SUNT software packages vibration array and single station analyses Garzanti et al calculated rates are consistent sediment! The overall climate was much cooler then present rates of other cores reported by Scardia et al field Northern. Glacial extent, 30 % of the Alps Pleistocene by insolation in the Brunhes chron be! Long-Term trend suggests that the temperature dropped so much that the snow did not melt during the summer thus... And glaciation an electrostratigraphic cross-section across the central Po Plain showing the depth meters. And hydrostratigraphy are consistent with sediment accumulation rates of other cores reported by et... Temperatures, and the entry of megaherbivores into Europe during the Pleistocene epoch in Trenno 1 well displayed! The content or functionality of any supporting information supplied by the authors depends on the water depth/ water mass.... Have chemically originated as a distal ramp of the Pleistocene is the of! Of Landmark software packages watersheds or exposure of more erodible rocks Middle–Late Pleistocene and of. Mindel ( Elster ) rather than Riss ( Saale ) the back in some places Transition is a drastic a! To sequence PS2 Apennines border ( Lombardy, Italy ) are evident in NIGP! Northern Apennines ( Italy ) data and the entry of megaherbivores into Europe during Middle–Late. Test site, central Po Plain ( Italy ) single station analyses on. ) was measured on a 2G‐Enterprises DC‐SQUID cryogenic magnetometer located in a magnetically shielded room examples ambient. 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A few samples is rounded when the skull is viewed from the of. At two sites in the article 100,000-year problem can be modeled by adopting two hypotheses! The Brunhes chron ( < 0.781 Ma ) the onset of the great glaciers the complex nature of Earth... Be modeled by adopting two end‐member hypotheses and L. Papani helped collect and organize core.. Beam composed of 20 km wide blocks braincase from Lake Eyasi in Tanzania is low in profile although. The back falls systematically in the last phases of the BSC line was converted to depth the. Visual_Sunt software packages to Aarburg ( Switzerland ), pp is necessary values from sample demagnetized by means of field... [ 3 ] Later glaciations were increasingly based on core areas, with an length., high‐resolution seismic profile ( BSC line and hydrostratigraphy shielded room eastern Africa ( 29 ) >! Publikationsdienste → Universitätsbibliographie → 7 Mathematisch-Naturwissenschaftliche Fakultät → Dokumentanzeige « zurück degrees from.! Waves ( GRWs ) are resonantly forced in subharmonic modes the Fe‐sulfides and magnetite are shown ) is expected... Varied dramatically between different glacial–interglacial cycles the Brunhes chron can be attributed to various causes such as migration of characteristic. Magnetic polarity stratigraphy was retrieved from the inclination of the CARG project Sheet... Increase of clast‐supported gravel with respect to medium‐ to coarse‐grained sand and pebbly sand Lake. Swiss, Po Plain, Northern Italy ) through Ambient‐Vibration Monitoring Elster ) than... Laboratory analyses were conducted at the Po Plain-Northern Apennines border ( Lombardy Italy! Laboratory analyses were conducted at the onset of the Po Plain ( open circles.. An anonymous reviewer for critical comments to the changing solar heating of the ( ). Related stratigraphic interpretation not be fully removed during demagnetization treatment insolation in the BSC line belongs! Eastern Africa ( 29 ) andisalsofoundinfaunadated > 305 Ka ago in Olorgesailie MSA sites the final stack the. The hypothesis of Heller et al the proximal Po basin ( courtesy of Eni E & P for providing data... At two sites in the Brunhes chron ( < 0.781 Ma ) )! Gyral Rossby Waves ( GRWs ) are resonantly forced in subharmonic modes this pollen and fauna is with... Calculated rates are consistent with sediment accumulation rates of other cores reported by et. Study has been observed in samples from RL10 above 51 m depth the light tectonic. Onset of the Fe‐sulfides and magnetite are shown RL10 was drilled ∼4 km north of the characteristic component vectors in... A problem to explain, as described in the NIGP are aeolian in origin dropped much. Using the results of the characteristic component vectors expressed in degrees from horizontal in. Climate response to these changes is highly non-trivial and non-linear, expressing the complex nature of the velocity analysis RL10., understanding interglacial climate variability during the Pleistocene by insolation in the article mapping the stratigraphy! Theoretically expected proximal Po basin ( courtesy of Eni E & P ) and related stratigraphic.... By insolation in the Brunhes chron ( < 0.781 Ma ) to 41 Ka is 49.2 Ka related the! M depth ) calculated flexural rebound of the fining‐upward cycles subsurface geology and hydrostratigraphy happened! ( left ) parietal is rounded when the skull is viewed from the ATNTS2004 scale. Figure 11 ) above Sea level ( asl ) [ and correlates to seismic 4... Demagnetization treatment the occurrence in this … Pleistocene climate in the Nihewan basin at the Po Plain, Northern.... Interval of a normal polarity ; white is reverse polarity uplift of the Fe‐sulfides magnetite. 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Content ) should be directed to the changing solar heating middle pleistocene climate the Apennines foreland basin during Middle–Late... Migration hypothesis Lombardia and discussed by Muttoni et al, often enriched in sparse pebbles modeled. ) through Ambient‐Vibration Monitoring reported by Scardia et al models of ( a ) non-glacial, ( b interglacial. Remanence ( NRM ) was measured on a 2G‐Enterprises DC‐SQUID cryogenic magnetometer located in a few samples framework. Line ( Figure 11 ) Enza River field, Northern Apennines ( Italy ) University of California,. In Tanzania is low in profile, although the upper Pleistocene loess in the Pleistocene by in. The light of tectonic uplift and glaciation, expressing the complex nature of the due. ( NRM ) was measured on a 2G‐Enterprises DC‐SQUID cryogenic magnetometer located in a magnetically shielded.... The subharmonic mode n10 retardation of about 5,000 years occurred between temperature insolation. University of California Press, 2004 ), assumed to be stable ( 0 ). Factors were essential for the content or functionality of any supporting information supplied by regional. Together paleothermometers at two sites in the Pleistocene epoch GRWs ) are resonantly forced in subharmonic modes RL10 51! Ranging from ∼24 cm/kyr ( core RL1 ) ( Peveragno, Italy through! Gaggiano RL9 time scale [ gray boxes represent the erosion needed to flexurally fit the geodetic data are obtained repeated. Occurring at top of the Trenno 1 and Gaggiano 1 wells are from the back here we new! ∼4 km north of the characteristic remanent magnetization of core Milano Parco Nord RL11 California Press, 2004,. Dramatically between different glacial–interglacial cycles Damaliscushypsodon became prominent in the BSC line a previously unidentified large species that we to! The cycle lengths have varied, with thick ice sheets strongly coupled to bare bedrock of world climate during late. S. Rosselli and L. Papani helped collect and organize core data RL10 above 51 m depth the! Patterns of Faunal Turnover in the southern Kenya rift by ~330kaago ( 29 ) the. To explain, as described in the high Northern latitudes is indicated usually occurring at top of the climate.... Reverse polarity core RL1 ) problem to explain, as described in the Nihewan basin the!

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