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Questa tesi di dottorato presenta un'indagine completa sulla dinamica dei sedimenti nel bacino idrografico del fiume Minjiang (Cina) e nel deserto del Thar occidentale (Pakistan). Il fiume Minjiang è delimitato dalle unità geologiche del dominio Songpan Ganzi, (tettonicamente attivo) e dal sistema di faglie del Longmenshan. L’analisi dettagliata di provenienza del bilancio sedimentario, che include le caratteristiche petrografiche e mineralogiche dei sedimenti appartenenti alle diverse unità geologiche, ha permesso di tracciare i diversi contributi che le varie unità rocciose forniscono al budget sedimentario totale. Le sabbie del fiume Minjiang sono caratterizzate da quarzo e feldspati (con un contenuto all’incirca uguale di K-feldspato e plagioclasio) provenienti dai graniti triassici. Le rocce sedimentarie del Triassico invece forniscono sabbie ricche in quarzo e frammenti di rocce associati con un bassa concentrazione di minerali pesanti (tormalina, apatite, anfibolo e zircone). Le unità del periodo Siluriano mostrano invece una chiara distribuzione polimodale di zirconi e i risultati delle analisi sulla loro età suggeriscono una provenienza da rocce del periodo Toniano, sottolineando l'importanza del basamento neoproterozoico nella dinamica dei sedimenti. Il deserto del Thar (regione del Cholistan e del Sindh) è un importante bacino sedimentario situato nell'Asia sudoccidentale e confinante a est con il sistema di drenaggio del fiume Indo. La composizione principale e i minerali pesanti presenti nelle sabbie eoliche della zona del Cholistan (Pakistan nord-occidentale) mostrano una similarità con la composizione dei sedimenti provenienti dagli affluenti dell’Himalaya, mentre la sabbia eolica della regione del Sindh (Pakistan meridionale) contiene una suite di minerali pesanti simile a quella della sabbia dell’Indo che è in gran parte fornita dall’erosione del Karakorum e del Kohistan. L'età U-Pb degli zirconi detritici non mostra una netta differenza t, This PhD thesis presents a comprehensive investigation into sediment dynamics in the segmented Minjiang River and the western Thar Desert, utilizing an integrated provenance approach. The Minjiang River is bounded by the tectonically active Songpan Ganzi and the central to southern Longmenshan fault system. A detailed provenance budget analysis, incorporating geological domains and distinct petrographic and heavy-mineral fingerprints, reveals the intricate contributions of various rock units to sediment supply. In the Minjiang River, the results identify quartzo-feldspathic sands within Triassic granites, featuring subequal K-feldspar and plagioclase content. The Triassic strata exhibit varied quartzo-lithic sand compositions. The study reveals a rich suite of minerals in recycled sands, including tourmaline, apatite, amphibole, and zircon. Silurian units display polymodal zircon distributions. Zircon age spectra suggest Tonian source terranes, emphasizing the importance of the Neoproterozoic basement in sediment dynamics. The Thar Desert is a major sediment depocenter in southwestern Asia and borders the Indus drainage system to its east. Bulk petrography and heavy mineral data from eolian sand in Cholistan (NE Pakistan) show close similarity with that of Himalayan tributaries, whereas eolian sand in Sindh (S Pakistan) contains heavy-mineral suites close to those of Indus sand largely supplied by erosion of the Karakorum and Kohistan. U-Pb detrital-zircon ages is not showing a sharp difference between dune sands in Sindh and Cholistan, except for revealing somewhat greater supply from the Himalaya in Cholistan and from the Karakorum, Kohistan and Nanga Parbat in Sindh. Bulk sediment isotope data indicates a stronger influence from mafic source rocks in Sindh as compared to the Cholistan. The Indus delta and lower reaches appear to be the greatest supplier, but with significant influence from Himalaya-derived tributaries in Cholistan but less influence from that sou

This work explores the significance of sedimentary proxies recorded within the Paleogene fine-grained detritus of the Adriatic foredeep (Northern Italy). Such sequences represent the only sedimentary record describing the source-to-sink system delivering detritus from the growing Alpine belt to the basin during the Eocene – Oligocene boundary. The combination of x-ray powder diffractometric, petrographic, SEM-EDS and biostratigraphic analyses on more than twenty samples from the Ternate-Travedona Formation, the Chiasso Formation, and the Villa Olmo Conglomerate allowed to identify the source areas of detritus and potential fluvial paleo-drainages, possibly ascribable to two different sectors of the Southalpine domain. Comparison between these results and the petrographic composition of the Cretaceous wedge in the same area opens to the possibility that Cenozoic drainages were inherited from more limited paleo-drainages developed during the end of the Mesozoic. Results of provenance analysis also gives new insights on how detrital compositions may vary in function of grain-size in tropical-subtropical environments.

This work is aimed at illustrating one of the most engaging geoparks in Europe, the Gole della Breggia Geopark. By following its geotrail, the visitors can observe a great deal of features that encompass a wide variety of sedimentary, stratigraphic, tectonic and paleogeographic processes. Its contents are popularized by a comprehensive geotrail that encompasses 23 geostops, enriched with explanatory panels, which enable viewers to gain an overall picture of the complex processes that led to the present-day configuration of the outcrops encountered in the geopark. We have selected five significative outcrops, which we have regarded as fully-fledged geosites, and which encompass the whole 170-million-year interval, from Early Jurassic to Late Miocene times, during which the rocks of the geopark were deposited and deformed. We have performed an assessment of the five geosites, using the most common criteria that can be applied for geosite evaluation. The results of the assessment show that the most valuable geosites are the Lombardian Maiolica, and the Limestone with Pelagic Bivalves. All five geosites, thanks to a QR code added to each figure along the text, can be viewed as virtual geosites (VGs), integrated by 360° videos.

Glacier surfaces are highly heterogeneous mixtures of ice, snow, light-absorbing impurities and debris material. The spatial and temporal variability of these components affects ice surface characteristics and strongly influences glacier energy and mass balance. Remote sensing offers a unique opportunity to characterize glacier optical and thermal properties, enabling a better understanding of different processes occurring at the glacial surface. In this study, we evaluate the potential of optical and thermal data collected from field and drone platforms to map the abundances of predominant glacier surfaces (i.e., snow, clean ice, melting ice, dark ice, cryoconite, dusty snow and debris cover) on the Zebrù glacier in the Italian Alps. The drone surveys were conducted on the ablation zone of the glacier on 29 and 30 July 2020, corresponding to the middle of the ablation season. We identified very high heterogeneity of surface types dominated by melting ice (30% of the investigated area), dark ice (24%), clean ice (19%) and debris cover (17%). The surface temperature of debris cover was inversely related to debris-cover thickness. This relation is influenced by the petrology of debris cover, suggesting the importance of lithology when considering the role of debris over glaciers. Multispectral and thermal drone surveys can thus provide accurate high-resolution maps of different snow and ice types and their temperature, which are critical elements to better understand the glacier’s energy budget and melt rates.

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Jonell, T., Giosan, L., Clift, P., Carter, A., Bretschneider, L., Hathorne, E., Barbarano, M., Garzanti, E., Vezzoli, G., & Naing, T. No modern Irrawaddy River until the late Miocene-Pliocene. Earth and Planetary Science Letters, 584, (2022): 117516, https://doi.org/10.1016/j.epsl.2022.117516., The deposits of large Asian rivers with unique drainage geometries have attracted considerable attention due to their explanatory power concerning tectonism, surface uplift and upstream drainage evolution. This study presents the first petrographic, heavy mineral, Nd and Sr isotope geochemistry, and detrital zircon geochronology results from the Holocene Irrawaddy megadelta alongside modern and ancient sedimentary provenance datasets to assess the late Neogene evolution of the Irrawaddy River. Contrary to models advocating a steady post-middle Miocene river, we reveal an evolution of the Irrawaddy River more compatible with regional evidence for kinematic reorganization in Myanmar during late-stage India-Asia collision. Quaternary sediments are remarkably consistent in terms of provenance but highlight significant decoupling amongst fine and coarse fraction 87Sr/86Sr and due to hydraulic sorting. Only well after the late Miocene do petrographic, heavy mineral, isotope geochemistry, and detrital zircon U–Pb results from the trunk Irrawaddy and its tributaries achieve modern-day signatures. The primary driver giving rise to the geometry and provenance signature of the modern Irrawaddy River was regional late Miocene (≤10 Ma) basin inversion coupled with uplift and cumulative displacement along the Sagaing Fault. Middle to late Miocene provenance signatures cannot be reconciled with modern river geometries, and thus require significant loss of headwaters feeding the Chindwin subbasin after ∼14 Ma and the northern Shwebo subbasin after ∼11 Ma. Large-scale reworking after ∼7 Ma is evidenced by modern Irrawaddy River provenance, by entrenchment of the nascent drainage through Plio-Pleistocene inversion structures, and in the transfer of significant sediment volumes to the Andaman Sea., TNJ was supported in initial stages of this project by a Postdoctoral Research Fellowship at UQ and software support by LSU. LG thanks support from the Andrew W. Mellon Foundation via Woods Hole Oceanographic Institution. The Charles T. McCord chair at LSU funded coring and detrital zircon U–Pb geochronology essential to the study.