Environmental variability between the penultimate deglaciation and the mid Eemian: Insights from Tana che Urla (central Italy) speleothem trace element record
Introduction
Investigations of the climate and environmental dynamics associated with deglaciations and the onset of interglacial periods are important for addressing key issues regarding the effects of rapid warming, as is expected in the near future. The Penultimate Deglaciation, corresponding to Termination II (TII) in the marine record (Lisiecki and Raymo, 2005), and the following warm stage, the Last Interglacial (LIG or Eemian interglacial in the European pollen stratigraphy), spanning the period ca. 140–110 ka, are among the best documented in the geological record. They have been the subject of a number of paleoclimate studies for over a century (e.g. Govin et al., 2015, Kukla et al., 2002, Shackleton et al., 2003). However, discrepancies still exist regarding timing and internal variability, as well as on the expression of this variability in the marine and in the terrestrial realms (e.g. Drysdale et al., 2009, Marino et al., 2015, Martrat et al., 2014). In particular, within TII, the timing and expression on land of Heinrich event 11 (H11), i.e., the millennial-scale episode of North Atlantic cooling and ice-rafted-debris (IRD) recorded in marine records from the sub-polar to the western Mediterranean between ca. 134 and 130 ka (e.g. Martrat et al., 2014, Jiménez-Amat and Zahn, 2015, Marino et al., 2015), are still matter of debate. Due to the scarcity of absolute age constraints in most archives covering TII and the LIG, various stratigraphic alignments to different reference chronologies have been used to link ice core, marine and terrestrial records (e.g. Govin et al., 2015, Zanchetta et al., 2016a). However, each of those approaches relies on different paleoclimate assumptions. They often regard synchronicity between climatic events recognized in marine records and those in terrestrial archives, and the paleoclimatic meaning of the compared proxies. This makes difficult to evaluate the climatic feedback mechanisms and the sequence of events over this time period (e.g. Masson-Delmotte et al., 2010, Landais et al., 2013, Zanchetta et al., 2016a). A detailed understanding of environmental parameters controlling the proxies selected for alignment among records is definitely of paramount importance.
Speleothems record palaeoenvironmental changes via a suite of geochemical properties that can be anchored to a robust radiometric U-Th chronology (Dorale et al., 2004). As a consequence of the development of high-resolution, well-dated speleothem records covering the TII-LIG period (e.g. Wang et al., 2001, Drysdale et al., 2009), several attempts have been made to refine the chronologies of marine sediments and ice cores by using climatic alignments to the most common tracer measured on speleothems, the oxygen stable isotope composition of the calcite δ18O (e.g. Drysdale et al., 2009, Barker et al., 2011, Jiménez-Amat and Zahn, 2015, Marino et al., 2015). Changes in temperature, rainfall amount and rain sources are considered the dominant drivers of δ18O (e.g. Lachniet, 2009, McDermott, 2004). However, these changes are often interconnected and the dominant climatic parameter differ from one region to another, making it difficult to forcefully argue the “climatic” link between δ18O and the climate-sensitive properties measured in other archives (Govin et al., 2015). To overcome this issue and disentangle the different drivers of the δ18O changes, the assessment of the paleoclimatic meaning of additional proxies measured in speleothems and the extent to which they agree with the δ18O series, is of paramount importance. One widely exploited proxy is the stable isotope composition of carbon (δ13C), which has been used to infer local pedogenic, hydrological and/or cave ventilation processes (Genty et al., 2001a, Genty et al., 2003, Spötl et al., 2005). Another speleothem property is growth rate, which is mainly controlled by the supply of CO2 in the seepage water, drip discharge and temperature (Hellstrom and McCulloch, 2000, Genty et al., 2001b, Borsato et al., 2015). A third source of information is trace element composition. Interpretations of speleothem trace element records are usually more challenging than other properties, because the elemental variability arises from complex interactions between atmospheric inputs, vegetation/soil, karstic aquifer, primary speleothem crystal growth and post-deposition processes (Fairchild and Treble, 2009). However, the integration of information on local environmental features from elemental records in the wider paleoclimatic framework provided by stable isotopes can provide a robust multi-proxy basis by which to unravel the response of the local palaeoenvironment to regional- and wider-scale climatic changes. This also helps to shed light on environmental and climate parameters driving changes in the δ18O composition.
In this paper we investigate trace element changes (Mg, Sr, Ba, Al, Si, Zn, Y, P) from a flowstone core (TCUD4) from Tana che Urla Cave (TCU) in central Italy (Fig. 1) for the interval ca.133 ka to ca.124 ka. The δ18O and δ13C profiles of TCUD4 for the period ca.159 ka to ca.121 ka have already been discussed by Regattieri et al. (2014a). In this new work, we explore the factors driving trace element geochemical changes on centennial and millennial time scales. Then we compare the trace element results with the pre-existing stable isotope record and with the broader environmental changes inferred from previous studies from the region (e.g. Brauer et al., 2007, Couchoud et al., 2009, Drysdale et al., 2005, Drysdale et al., 2009, Milner et al., 2013, Tzedakis et al., 2003). This multiproxy approach allows us to assess in detail the changing environmental evolution at the TCU cave site during the period encompassing most of the Penultimate Deglaciation and the first part of the LIG. It also provides insights into the factors leading δ18O variability and on their links to regional and extra-regional climate changes.
Section snippets
Site and sample description
TCU is a sub-horizontal spring cave that opens at 620 m a.s.l. on the south-eastern side of the Apuan Alps, central Italy (Fig. 1). The cave characteristics have been discussed in previous studies (Regattieri et al., 2012, Regattieri et al., 2014a) and are only briefly summarized here. The cave has developed at the contact between meta-siliciclastics (Fornovolasco schist formation, Pandeli et al., 2004) and Triassic meta-dolomite (Grezzoni formations), and is crossed by a permanent stream. The
Methods
The isotopic record and age-model have been discussed by Regattieri et al. (2014a), and thus the related methods (uranium-series dating, age modeling and stable isotope analysis) are not further described here.
Background
The major features of the TCU stable isotope record for the period ca.133 to ca.124 ka (now covered by trace element results) were discussed by Regattieri et al. (2014a). They include the dramatic excursions towards lower δ18O values between 132.1 ± 1.8 ka and 131.0 ± 1.2 ka and two abrupt events of increased isotope values centered at 129.6 ± 1.0 ka and 126.1 ± 1.3 ka, both lasting about 1 kyr (Fig. 3). In the central Mediterranean, changes in continental carbonate δ18O (lacustrine and
Conclusions
The trace element (Mg, Ba, Sr, Si, Al, P, Y, Zn) record of a flowstone from Tana che Urla Cave (central Italy) spanning ca. 132 ka to ca. 124 ka period shows marked variations consistent with hydrological changes previously inferred from the stable isotope record (Regattieri et al., 2014a). Changes in element concentrations are linked to the hydrological state of the recharge system, to changes in the infiltration rate and in the capacity of the soil cover to retain the mineral flux, and to the
Acknowledgements
Funded by the Australian Research Council, Discovery Projects DP110102185. During analytical work, ER was supported by a Ph.D grant of the School of Graduate Studies Galileo Galilei (University of Pisa). We thank the Federazione Speleologica Toscana and Parco delle Alpi Apuane for supporting our work on Apuan Alps speleothems. We also thank C. Boschi and M. Guidi for use of facilities at the IGG-CNR, Pisa.
References (92)
- et al.
Millennial-scale versus long-term dynamics in the surface and subsurface of the western North Atlantic subtropical gyre during marine isotope stage 5
Glob. Planet. Change
(2013) - et al.
Hydrological conditions over the western Mediterranean basin during the deposition of the cold Sapropel 6 (ca. 175 kyr BP
Earth Planet. Sci. Lett.
(2002) - et al.
Sea–land oxygen isotopic relationships from planktonic foraminifera and speleothems in the Eastern Mediterranean region and their implication for paleorainfall during interglacial intervals
Geochim. Cosmochim. Acta
(2003) - et al.
Trace element distribution in annual stalagmite laminae mapped by micrometer-resolution X-ray fluorescence: implications for incorporation of environmentally significant species
Geochim. Cosmochim. Acta
(2007) - et al.
Evidence for enhanced Mediterranean thermohaline circulation during rapid climatic coolings
Earth Planet. Sci. Lett.
(2000) - et al.
Millennial-scale climate variability during the Last Interglacial recorded in a speleothem from south-western France
Quat. Sci. Rev.
(2009) - et al.
Palaeoclimatic implications of the growth history and stable isotope (δ18O and δ13C) geochemistry of a Middle to Late Pleistocene stalagmite from central western Italy
Earth Planet. Sci. Lett.
(2004) - et al.
Controls on trace element (Sr–Mg) compositions of carbonate cave waters: implications for speleothem climatic records
Chem. Geol.
(2000) - et al.
Trace elements in speleothems as recorders of environmental change
Quat. Sci. Rev.
(2009) - et al.
Intra-and inter-annual growth rate of modern stalagmites
Chem. Geol.
(2001)
Sequence of events from the onset to the demise of the Last Interglacial: evaluating strengths and limitations of chronologies used in climatic archives
Quat. Sci. Rev.
Timing and nature of the penultimate deglaciation in a high alpine stalagmite from Switzerland
Quat. Sci. Rev.
Origin and consequences of cyclic ice rafting in the northeast Atlantic Ocean during the past 130,000 years
Quat. Res.
Multi-proxy constraints on the climatic significance of trace element records from a New Zealand speleothem
Earth Planet. Sci. Lett.
Adsorbed silica in stalagmite carbonate and its relationship to past rainfall
Geochim. Cosmochim. Acta
Last interglacial surface water structure in the western Mediterranean (Balearic) Sea: climatic variability and link between low and high latitudes
Glob. Planet. Change
Last interglacial climates
Quat. Res.
Climatic and environmental controls on speleothem oxygen-isotope values
Quat. Sci. Rev.
Reconstruction of temperature in the Central Alps during the past 2000 yr from a δ18O stalagmite record
Earth Planet. Sci. Lett.
Similarities and dissimilarities between the last two deglaciations and interglaciations in the North Atlantic region
Quat. Sci. Rev.
EPICA Dome C record of glacial and interglacial intensities
Quat. Sci. Rev.
Palaeo-climate reconstruction from stable isotope variations in speleothems: a review
Quat. Sci. Rev.
Partition coefficients in calcite: examination of factors influencing the validity of experimental results and their application to natural systems
Chem. Geol.
Termination-II interstadial/stadial climate change recorded in two stalagmites from the north European Alps
Quat. Sci. Rev.
Evolution and demise of the Last Interglacial warmth in the subpolar North Atlantic
Quat. Sci. Rev.
Late warming and early cooling of the sea surface in the Nordic seas during MIS 5e (Eemian Interglacial)
Quat. Sci. Rev.
A continuous stable isotope record from the penultimate glacial maximum to the Last Interglacial (159–121ka) from Tana Che Urla cave (Apuan Alps, central Italy)
Quat. Res.
Mediterranean climate and oceanography, and the periodic development of anoxic events (sapropels)
Earth Sci. Rev.
Stable isotope records of Late Quaternary climate and hydrology from Mediterranean lakes: the ISOMED synthesis
Quat. Sci. Rev.
The significance of chemical, isotopic, and detrital components in three coeval stalagmites from the superhumid southernmost Andes (53 degrees S) as high-resolution palaeo-climate proxies
Quat. Sci. Rev.
Two mathematical models of Mg and Sr partitioning into solution during incongruent calcite dissolution: implications for dripwater and speleothem studies
Chem. Geol.
Magnesium and strontium systematics in tropical speleothems from western Pacific
Chem. Geol.
Marine isotope substage 5e and the Eemian interglacial
Glob. Planet. Change
Cave air control on dripwater geochemistry, Obir Caves (Austria): implications for speleothem deposition in dynamically ventilated caves
Geochim. Cosmochim. Acta
Tracking rainfall in the northern Mediterranean borderlands during sapropel deposition
Quat. Sci. Rev.
Comparison of high resolution sub-annual records of trace elements in a modern (1911–1992) speleothem with instrumental climate data from southwest Australia
Earth Planet. Sci. Lett.
Last Interglacial conditions in southern Europe: evidence from Ioannina, northwest Greece
Glob. Planet. Change
Coeval dry events in the central and eastern Mediterranean basin at 5.2 and 5.6 ka recorded in Corchia (Italy) and Soreq caves (Israel) speleothems
Glob. Planet. Change
Stratigraphic evidence for a “pluvial phase” between ca 8200-7100 ka from Renella cave (Central Italy)
Quat. Sci. Rev.
High resolution and precisely dated record of weathering and hydrological dynamics recorded by manganese and rare-earth elements in a stalagmite from Central China
Quat. Res.
A chemiostratigraphic study of the metadolomitic sequence of the southern side of Mount Corchia (Alpi Apuane, Italy)
Geol. Romana
Evidence for early warming and cooling in North Atlantic surface waters during the Last Interglacial
Paleoceanography
Hypogean microclimatology and hydrology of the 800–900 m a.s.l. level in the Monte Corchia Cave (Tuscany, Italy): preliminary considerations and implications for paleoclimatological studies
Acta Carsologica
800,000 years of abrupt climate variability
Science
NALPS: a precisely dated European climate record 120–60 ka
Clim. Past
Evidence for Massive Discharges of Icebergs into the North Atlantic Ocean during the Last Glacial Period
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