Papers by ADRIANO RIBOLINI
In this paper we illustrate the stratigraphy, geochronology, and geochemistry (major, minor, trac... more In this paper we illustrate the stratigraphy, geochronology, and geochemistry (major, minor, trace elements and Sr-isotopes) of a Holocene tephra layer found within coastal sedimentary deposits north of Caleta Olivia (Santa Cruz Province, Argentina). The stratigraphic succession comprises beach deposits with basal erosive surface resting on the local substrate (“Formacion Patagonia”) followed by a poorly developed paleosoil. The paleosoil is covered by a lenticular fine-grained (Mdφ: 5.2, 0.027 mm), well sorted (σφ: 1.2) volcanic ash layer and aeolian sands. The geochemical composition of shard fragments points to an origin from the Hudson volcano, located in the southern Andes, ca. 400 km to the west. The geochemistry, Sr-isotopes and the radiometric constraints (younger than the age of the underlying marine layer dated at ca. 4,100 a cal BP) further allow correlating this tephra with the so-called H2 eruption (ca. 3,900 a cal BP). This finding is of interest owing to the poor pres...
Ground wedge structures of cryogenic origin are common in the Quaternary sediments along the coas... more Ground wedge structures of cryogenic origin are common in the Quaternary sediments along the coast of the Patagonia, and their formation is related to climatic cold events experienced by this area in the Late Quaternary. The infilling sediments of two wedges generations were analyzed in the area of Puerto Deseado. Bulk chemistry (major elements), X-ray diffraction (XRD), morphoscopic observations with Scanning Electronic Microscope (SEM) and chemical analyses of volcanic glass shards were undertaken to provide indications about infilling sediment provenience, along with chronological constraint for wedge formation. Bulk chemistry and XRD patterns indicate a significant SiO2- enriched composition of the sediment infilling compared to the most of the loess deposits of the North Argentina and the present day dust originated in Patagonia. This was interpreted as due to the nature of the bedrock present over the Deseado Massif. SEM morphoscopic characteristics of glass shards evidence ty...
Glaciations on Ophiolite Terrain in the North Pindus Mountains, Greece: New Geomorphological Insights and Preliminary 36cl Exposure Dating
SSRN Electronic Journal, 2021
Manuscript Number: jgs2017-038R1 Article Type: Research article Full Title: An Oldest Dryas glaci... more Manuscript Number: jgs2017-038R1 Article Type: Research article Full Title: An Oldest Dryas glacier expansion in the Pelister Mountain (Former Yugoslavian Republic of Macedonia) according to 10Be cosmogenic dating Short Title: Cosmogenic age of an Oldest Dryas glacial advance Corresponding Author: Adriano Ribolini, Ph.D Universita degli Studi di Pisa Pisa, ITALY Corresponding Author E-Mail: [email protected] Other Authors: Monica Bini Ilaria Isola Matteo Spagnolo Giovanni Zanchetta Ramón Pellitero Silke Mechernich Raphael Gromig Tibor Dunai Bernd Wagner Ivica Milevski Manuscript Classifications: Dating (radiometric, absolute, etc); Geomorphology Additional Information: Question Response Are there any conflicting interests, financial or otherwise? No
Geografia Fisica E Dinamica Quaternaria, 2015
Renowned since the Roman Period for the extraction of precious marble, the Apuan Alps (northern T... more Renowned since the Roman Period for the extraction of precious marble, the Apuan Alps (northern Tuscany) are an extraordinary region of natural and cultural heritage in the Mediterranean basin and contain a large number of geosites of international and national interest. The great variety of morphologic and topographic contexts, ranging from the coastal plain of Versilia to the rugged, harsh landscape in the interior, makes this region remarkable for its peculiar geologic and geomorphologic setting. Two map sheets are appended to this paper: (1) a geomorphological map of Apuan Alps Regional Park and its immediate surroundings at a scale of 1:50,000 and (2) two thematic maps at a scale of 1:100,000 ('Neotectonic Map' and the 'Map of Selected Sites of Geomorphological Significance') and other four thematic maps at a scale of 1:200,000 that present the relief, slope aspects, drainage networks, and climatic elements of the region.
Andean Geology, 2021
In this paper we illustrate the stratigraphy, geochronology, and geochemistry (major, minor, trac... more In this paper we illustrate the stratigraphy, geochronology, and geochemistry (major, minor, trace elements and Sr-isotopes) of a Holocene tephra layer found within coastal sedimentary deposits north of Caleta Olivia (Santa Cruz Province, Argentina). The stratigraphic succession comprises beach deposits with basal erosive surface resting on the local substrate (“Formación Patagonia”) followed by a poorly developed paleosoil. The paleosoil is covered by a lenticular fine-grained (Mdφ: 5.2, 0.027 mm), well sorted (σφ: 1.2) volcanic ash layer and aeolian sands. The geochemical composition of shard fragments points to an origin from the Hudson volcano, located in the southern Andes, ca. 400 km to the west. The geochemistry, Sr-isotopes and the radiometric constraints (younger than the age of the underlying marine layer dated at ca. 4,100 a cal BP) further allow correlating this tephra with the so-called H2 eruption (ca. 3,900 a cal BP). This finding is of interest owing to the poor pres...
Science Advances, 2020
Reconstructed palaeoprecipitation reveals a persistent SCAND-like circulation and southerly storm... more Reconstructed palaeoprecipitation reveals a persistent SCAND-like circulation and southerly storm track during the Younger Dryas.
Vegetation History and Archaeobotany, 2020
We used pollen, plant-macrofossil, and charcoal records to unfold local long-term timberline shif... more We used pollen, plant-macrofossil, and charcoal records to unfold local long-term timberline shifts and changes in vegetation composition in relation to fire activity at the modern upper forest limit (ca. 2000 m asl) in the Mont Bégo area. The area is an iconic place for Alpine archaeology because it bears thousands rock-art engravings whose age cannot be directly assessed. Our new record confirms the occurrence of distinct land-use phases (7450-7150, 6200-4900, and 4250-3700 cal BP), as suggested by prior studies based on rock-art typology. Moreover, the macrofossil-inferred vegetation reconstruction (co-dominance of Pinus and Betula) suggests that early-Holocene conditions were moister than in dry inner-alpine valleys, where Larix decidua played a more important role, both in past as well as in modern timberline forests. After 8000 cal BP, the timberline shifted to higher elevation and mixed Abies alba and Pinus cembra stands established around the study site. These firesensitive tree populations were definitely replaced during the Bronze Age (around 4000 cal BP) by L. decidua that still dominates the subalpine forests in the area today. Our study supports the notion that while the range (or realized climatic niche) of A. alba has been reduced at the colder-end of its natural distribution that of L. decidua has been widened by land-use changes and fire disturbances to create high-alpine pasture woodlands.
CATENA, 2020
Rock-glacier sediment transfer and ice melting can impact surface waters located downstream. Howe... more Rock-glacier sediment transfer and ice melting can impact surface waters located downstream. However, there is a lack of knowledge on the influence of rock-glacier dynamics on the geochemical, hydrochemical, and ecological characteristics of adjacent impounded surface waters. In the Col d'Olen area (Long-Term Ecological Research site, NW Italian Alps), an intact rock glacier terminates into a pond and solute-enriched waters originating from the rock glacier flow into the pond through a subsurface hydrological window. In this study, we performed geophysical and ground surface temperature measurements. Moreover, we sampled soils and sediments in different compartments of the investigated rock-glacier -pond system and we further sampled benthic invertebrates in the pond. Cold ground thermal regime, ground-ice presence, and coarse debris cover on the rock glacier together with its lithology (serpentinites) influence the rock-glacier geochemistry and ecology with respect to surrounding areas. Pond geochemistry is affected by transfer of trace-metal-enriched fine-grained debris and meltwaters from the rock glacier. Enhanced bioavailability of serpentinite-associated trace metals was proved, with concentrations of Ni and Cr in benthic invertebrates up to 384 and 110 mg kg -1 d.w., respectively, potentially exerting toxic effects on pond biota. The advancing movement of the rock glacier not only has delivered sediments to the pond, but it has progressively filled the valley depression where the pond is located, creating a dam that could have modified the level of impounded water. This process likely constituted a sediment trap in which serpentinitic rock-glacier sediments could be deposited at the pond bottom, with related geochemical and ecological implications. This study illustrates the importance of rock glaciers in influencing the characteristics of downstream freshwater bodies and highlights the need to improve our knowledge about climate-change-related impacts of rock-glacier dynamics on alpine headwaters.
Earth-Science Reviews, 2018
The relatively warm climate conditions prevailing today in the Mediterranean region limit cold ge... more The relatively warm climate conditions prevailing today in the Mediterranean region limit cold geomorphological processes only to the highest mountain environments. However, climate variability during the Late Pleistocene and Holocene has led to significant spatio-temporal variations of the glacial and periglacial ___domain in these mountains, including permafrost conditions. Here, we examine the distribution and evolution of permafrost in the Mediterranean region considering five time periods: Last Glaciation, deglaciation, Holocene, Little Ice Age (LIA) and present-day. The distribution of inactive permafrost-derived features as well as sedimentary records indicates that the elevation limit of permafrost during the Last Glaciation was between 1000 m and even 2000 m lower than present. Permafrost was also widespread in non-glaciated slopes above the snowline forming rock glaciers and block streams, as well as meter-sized stone circles in relatively flat summit areas. As in most of the Northern Hemisphere, the onset of deglaciation in the Mediterranean region started around 19-20 ka. The ice-free terrain left by retreating glaciers was subject to paraglacial activity and intense periglacial processes under permafrost conditions. Many rock glaciers, protalus lobes and block streams formed in these recently deglaciated environments, though most of them became gradually inactive as temperatures kept rising, especially those at lower altitudes. Following the Younger Dryas glacial advance, the Early Holocene saw the last massive deglaciation in Mediterranean mountains accompanied by a progressive shift of permafrost conditions to higher elevations. It is unlikely that air temperatures recorded in Mediterranean mountains during the Holocene favoured the existence of widespread permafrost regimes, with the only exception of the highest massifs exceeding 2500-3000 m. LIA colder climate promoted a minor glacial advance and the spatial expansion of permafrost, with the development of new protalus lobes and rock glaciers in the highest massifs. Finally, post-LIA warming has led to glacial retreat/disappearance, enhanced paraglacial activity, shift of periglacial processes to higher elevations, degradation of alpine permafrost along with geoecological changes.
The New phytologist, Jan 18, 2018
Comment on Carcaillet & Blarquez (2017) 'Fire ecology of a tree glacial refugium on a nunatak wit... more Comment on Carcaillet & Blarquez (2017) 'Fire ecology of a tree glacial refugium on a nunatak with a view on Alpine glaciers'. The questions as to where and how trees survived the Quaternary ice ages are key for understanding climate-driven range expansion processes and the influence of ice-age legacies on current mid-and high-latitude biodiversity patterns . Such questions have long intrigued plant ecologists, biogeographers and palaeoecologists and have recently become the focus of combined molecular-ecological and biogeographical studies . The classic southern-refugia paradigm postulates treeless landscapes in central Europe and at the margins of the continental and Alpine ice-sheets for the time of the Last Glacial Maximum (LGM; c. 23 000-19 000 calendar years before present (cal yr BP, where 0 cal yr BP = AD 1950), that is, the interval representing the most extreme conditions of the Last Glacial). Widespread cold-adapted alpine and arctic plants and boreal dwarf shrubs are documented to have occurred north of the Alps , while small populations of temperate and boreal trees persisted in southern European peninsulas (Iberia, Italy, and the Balkans) . Boreal and mountain conifers (e.g. Larix decidua Mill. and Pinus cembra L.) occurred at more northerly locations (up to c. 46°N) in eastern Europe, and grew closer to the southern margin of the Alpine and Carpathian ice-caps than temperate trees (Willis, 2000;. This view has been challenged by the alternative interpretation that temperate plant species could have survived the LGM further north in locally favourable conditions as small populations that may be hard to detect with palaeoecological tools (e.g. V€ aliranta et al., 2011). Recently, Carcaillet & Blarquez (2017) presented evidence for the occurrence of an LGM 'tree refugium' located at c. 2200 m above sea level (asl) on a nunatak (a mountain top or peak emerging from or at the edge of an ice sheet or glacier) on the western flank of the European Alps. The reported presence of L. decidua and P. cembra plant macrofossils during the LGM in sediments from Lake Miroir, a site located close to modern treeline altitude (TLA), challenges the consensus on the LGM distributions of trees in Europe. The authors further provided evidence of fire occurrence
Quaternary Research, 2018
While proxy records have been used to reconstruct late Quaternary climate parameters throughout t... more While proxy records have been used to reconstruct late Quaternary climate parameters throughout the European Alps, our knowledge of deglacial climate conditions in the Maritime Alps is limited. Here, we report temperatures recorded by a new and independent geochemical technique—cosmogenic noble gas paleothermometry—in the Maritime Alps since the last glacial maximum. We measured cosmogenic 3He in quartz from boulders in nested moraines in the Gesso Valley, Italy. Paired with cosmogenic 10Be measurements and 3He diffusion experiments on quartz from the same boulders, the cosmogenic 3He abundances record the temperatures these boulders experienced during their exposure. We calculate effective diffusion temperatures (EDTs) over the last ∼22 ka ranging from 8°C to 25°C. These EDTs, which are functionally related to, but greater than, mean ambient temperatures, are consistent with temperatures inferred from other proxies in nearby Alpine regions and those predicted by a transient general...
The Holocene, 2017
This paper concerns the relative sea-level changes associated with the Atlantic Patagonian coast ... more This paper concerns the relative sea-level changes associated with the Atlantic Patagonian coast derived from sea-level index points whose elevation was determined by a differential global position system (DGPS). Bioencrustations from outcrops located near Camarones, Chubut, Argentina, consist of autochthonous deposits characterized by Austromegabalanus psittacus (Molina, 1782), encrusting acervulinid foraminifera, coralline red algae and bryozoans. The association of the different organisms is interpreted as being associated with an intertidal environment, and they have been used as index points to establish the relative sea-level position. The main conclusion is that the relative sea-level between c. 7000 and 5300 cal. yr BP was in the range of c. 2-4 m a.s.l., with a mean value of c. 3.5 m a.s.l. Our data seem to support the existence of different rates of relative sea-level fall in different sectors of Atlantic Patagonia during the Holocene and highlight the importance of a more precise and accurate relative sea-level estimation by producing new data and revisiting the indicative meaning of most of the indicators so far used in the area.
Quaternary International, 2017
This study presents the first cosmogenic 36Cl surface exposure data from a moraine in the Former ... more This study presents the first cosmogenic 36Cl surface exposure data from a moraine in the Former Yugoslav Republic of Macedonia (FYROM). Five limestone boulders from a terminal moraine in the Galicica Mountains (40. 94°N, 20.83°E, 2050 m a.s.l.) were used for cosmogenic 36Cl surface exposure dating. The 36Cl concentrations from the five boulders are identical within their measurement uncertainties ruling out major effects of inheritance, erosion, or snow cover. The calculated ages are very consistent ranging from 11.3 to 12.8 ka (mean 12 ka) after applying a Caspallation production rate of 56 at g-1 a-1 (LSD scaling) and correction for 5 mm ka-1 carbonate weathering and 2 % snow shielding. The applied corrections for weathering and snow shielding cause a shift to older ages in the order of magnitude of ca. 5 % on average, making the production rate the main impact on exposure ages. The ages point to a moraine formation during the Younger Dryas period, consistent with the timing of the last deglaciation in the Galicica Mountains derived from previous geomorphological studies in the area. The formation of a glacier was likely favoured by several topoclimatic factors, accounting for additional snow input. This interpretation is in line with regional studies on glaciation chronologies from Šara Range (FYROM/Republic of Kosovo), Retezat Mountains (Romania), Mount Orjen (Montenegro) and Durmitor (Montenegro). Lake sediment analyses of lakes Prespa (Republic of Albania/ FYROM/Greece), Maliq (Republic of Albania) and Dojran (FYROM/Greece) indicate that cold conditions promoted the formation of a local cirque glacier. However, studies of sediment records of the adjacent lakes Ohrid (Republic of Albania/FYROM) and Prespa do not indicate the presence of a proximal glaciation. An explanation might be a combination of the small size of the cirque glacier, generating only small amounts of debris, and the karstic bedrock, which hampers fluvial transport and acts by its aquifer system as a natural sediment trap, as the fluvial transport of the sediments to the lakes is absorbed by the karst system.
Journal of the Geological Society, 2017
Reply to the Reviewers Dear Editor, Thank you for the management of our submission and for provin... more Reply to the Reviewers Dear Editor, Thank you for the management of our submission and for proving helpful comments and suggestions. In the following pages we reply to all issues raised by the two reviewers and yourself. Reviewer 1: The paper presents interesting results in the dating of three moraine blocks, for which they provide very similar results. Despite the low number of samples, the remarkably homogeneous results obtained allow to include this moraine within a period of widespread glacial advance in the Mediterranean environment and, more generally, on a planetary scale. The work is very well written and very clear. However, it shows some methodological deficiencies, mainly in two fields: A) Chronological analysis of the samples: the manner of taking the samples and the field data is described in great detail, but no details are given of how the geochemical analyses, the calibration method, or the methods for isotope production have been performed. Besides, indicating that "standard laboratory procedures" have been adopted is not sufficient, since these can indeed vary widely. REPLY: The details about laboratory procedures are now included (lines 134-146). Moreover, the details of chemical analytical results are reported in a new Table placed in the supplementary material of the paper Furthermore, the analysis does not describe the values entered in the age calculator used to obtain the ages, nor does it indicate the spallation scaling scheme that has been chosen from the possible ones offered by the age calculator used, nor is it clear what the uncertainty values refer to. REPLY: The values entered in the age calculator are now isolated in Tab 1. The internal uncertainty (analytical uncertainties which are dominated by AMS uncertainties) and the external uncertainty (both analytical and production rate uncertainties) are both indicated in Tab. 2, following Balco et al. 2008 (Quaternary Geochronology 3, 174-195). In the discussion we refer only to the external uncertainty. Moreover, the scaling scheme for spallation is now2 referred at lines 229-230.
Journal of Maps, 2017
We present a geomorphological map (Main Map) of the lower plain of the Ceyhan River (Adana provin... more We present a geomorphological map (Main Map) of the lower plain of the Ceyhan River (Adana province, Turkey). Data from three field campaigns and remote sensing observations were managed in a GIS to produce a 1:25,000 scale map. The area, mostly formed by alluvial sediments, is characterized by intense fluvial dynamics with superimposed agricultural activity. Erosional processes prevail on rocky ridges partially bordering the plain on the north-eastern side. The alluvial plain is flanked by large alluvial fans on its eastern side, whereas the western limit consists of a smoothed and undistinguishable watershed. Alluvial and deltaic deposits close to the river mouth are bordered southward by nested coastal dunes, lagoons, swamps and marshes punctuating the coastal belt. This area was an important historical site, as documented by evidence of settlements from the Neolithic. The map is a useful tool to support further archaeological research.
Computers & Geosciences, 2016
Glacier reconstructions are widely used in palaeoclimatic studies and this paper presents a new s... more Glacier reconstructions are widely used in palaeoclimatic studies and this paper presents a new semi-automated method for generating glacier reconstructions: GlaRe, is a toolbox coded in Python and operating in ArcGIS. This toolbox provides tools to generate the ice thickness from the bed topography along a palaeoglacier flowline applying the standard flow law for ice, and generates the 3D surface of the palaeoglacier using multiple interpolation methods. The toolbox performance has been evaluated using two extant glaciers, an icefield and a cirque/valley glacier from which the subglacial topography is known, using the basic reconstruction routine in GlaRe. Results in terms of ice surface, ice extent and equilibrium line altitude show excellent agreement that confirms the robustness of this procedure in the reconstruction of palaeoglaciers from glacial landforms such as frontal moraines.
Geografia Fisica e Dinamicca Quaternaria
Glacial features were described for the first time on the Galicia Moun- tains, a mountain range s... more Glacial features were described for the first time on the Galicia Moun- tains, a mountain range separating the lakes of Ohrid and Prespa in Mace- donia. The geomorphological mapping of part of this range allowed to document the existence of frontal and lateral moraines, as well as trimlines, cirques and polished rocks. These glacial features allowed the reconstruc- tion of the original topography of the glaciers that deposited the frontal moraines. The Equilibrium Line Altitude (ELA) of three different phases of expansion was calculated (ca. 1850 m, ca. 2000 m and 2130 m a.s.l.) through the Area-Altitude Balance Ratio (AABR) method, and correlated with the values available for the Balkan region and northern Greece. An at- tribution to Last Glacial Maximum (LGM) and Lateglacial (Oldest and Younger Dryas) was argued for the glacial phases of Galicica Mountains, in agreement with the ELAs of dated moraines in the region, as well as in the Apennines and Maritime Alps. Through the extrap...
Journal of Maps, 2011
This paper presents a 1:100,000 scale geomorphologic map of the Northeastern sector of San Jorge ... more This paper presents a 1:100,000 scale geomorphologic map of the Northeastern sector of San Jorge Gulf (Chubut Province) in Patagonia, Argentina, covering more than 1,000 km 2 . Derived from remote sensing data and validated by three field surveys, it has been compiled in order to understand the past and recent evolution of the area with particular reference to sea-level oscillation studies, for which this map is the 15 basic tool. The very low human impact and rates of dynamic landscape change allow the preservation of extensive palaeo deposits and landforms, including those indicative of sea-level variations. The relative change of sea level dominates landscape evolution, allowing the formation of widespread marine and lagoon deposits often interfingering with fluvial deposits and reworked by aeolian process in the framework of consequent beach progradation.
Quaternary Science Reviews, 2010
Ground ice of permafrost origin and sedimentary ice of glacial origin can coexist in locations wh... more Ground ice of permafrost origin and sedimentary ice of glacial origin can coexist in locations where rock glaciers and glaciers interacted, as well as in glacigenic sediments abandoned by a retreating glacier and subsequently exposed again to atmospheric cooling. Some of these geomorphological settings in the Central (Foscagno rock glacier) and Western Alps (Marinet and Schiantala rock glaciers, Schiantala debris-covered glacier, Maledia glacier) were explored by means of geoelectrical tomographies. The aim was that of inferring the presence of ice and cryologically interpreting electrical stratigraphies in order to test whether or not the internal structure of these landforms can be used for the reconstruction of recent permafrost and glacier evolution. Geomorphological data assisted these reconstructions and available borehole stratigraphies were used to calibrate the resistivities. Along with the ice-debris mixture, massive ice has also been found as lenses both at the apex and the front of the studied rock glaciers. These lenses of sedimentary origin are thought to be transferred from a glacier snout to sectors of rock glacier and eventually embedded into the permafrost creep. The scarcity of frozen debris in the mid-upper part of the rock glaciers -as revealed by low resistivity values -can be due to the disruptive effect of the over-riding glacier over the permafrost. The near-surface sedimentary ice masses detected along the slopes of the studied glacial cirques are interpreted as or debris-covered terminations of the glaciers still visible upward, or as fragments of it detached by the main bodies. These ice masses are locally associated to medium-high resistive sediments, consistent with permafrost occurrence. This indicates that the non-glacial environment established during the deglaciation allowed the onset of frozen sediments formation. Overall, the results indicate that internal structure of rock glaciers and recent-deglaciated slopes can store the different climate-related episodes occurred in a specific area, such as those linked to the shifting between glacial to criotic condition and vice-versa.
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Papers by ADRIANO RIBOLINI