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Geomorphology of Ulu Peninsula James Ross Island Antarctica.Pdf Journal of Maps ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/tjom20 Geomorphology of Ulu Peninsula, James Ross Island, Antarctica Stephen J. A. Jennings, Bethan J. Davies, Daniel Nývlt, Neil F. Glasser, Zbyněk Engel, Filip Hrbáček, Jonathan L. Carrivick, Bedřich Mlčoch & Michael J. Hambrey To cite this article: Stephen J. A. Jennings, Bethan J. Davies, Daniel Nývlt, Neil F. Glasser, Zbyněk Engel, Filip Hrbáček, Jonathan L. Carrivick, Bedřich Mlčoch & Michael J. Hambrey (2021) Geomorphology of Ulu Peninsula, James Ross Island, Antarctica, Journal of Maps, 17:2, 125-139, DOI: 10.1080/17445647.2021.1893232 To link to this article: https://doi.org/10.1080/17445647.2021.1893232 © 2021 The Author(s). Published by Informa View supplementary material UK Limited, trading as Taylor & Francis Group on behalf of Journal of Maps Published online: 08 Mar 2021. Submit your article to this journal Article views: 135 View related articles View Crossmark data Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=tjom20 JOURNAL OF MAPS 2021, VOL. 17, NO. 2, 125–139 https://doi.org/10.1080/17445647.2021.1893232 SCIENCE Geomorphology of Ulu Peninsula, James Ross Island, Antarctica Stephen J. A. Jennings a, Bethan J. Davies b, Daniel Nývlt a,c, Neil F. Glasser d, Zbyněk Engel e, Filip Hrbáček a, Jonathan L. Carrivick f, Bedřich Mlčochc and Michael J. Hambrey d aPolar-Geo-Lab, Department of Geography, Faculty of Science, Masaryk University, Brno, Czech Republic; bCentre for Quaternary Research, Department of Geography, Royal Holloway University of London, Egham, UK; cCzech Geological Survey, Praha, Czech Republic; dCentre for Glaciology, Department of Geography and Earth Sciences, Aberystwyth University, Wales, UK; eDepartment of Physical Geography and Geoecology, Faculty of Science, Charles University, Praha, Czech Republic; fSchool of Geography, University of Leeds, Leeds, UK ABSTRACT ARTICLE HISTORY This study presents a 1:25,000 geomorphological map of the northern sector of Ulu Peninsula, Received 29 September 2020 James Ross Island, Antarctic Peninsula. The map covers an area of c. 250 km2, and documents Revised 17 February 2021 the landforms and surficial sediments of one of the largest ice-free areas in Antarctica, based on Accepted 17 February 2021 fi remote sensing and eld-based mapping. The large-scale landscape features are determined KEYWORDS by the underlying Cretaceous sedimentary and Neogene volcanic geology, which has been Geomorphology; sculpted by overlying ice masses during glacial periods. Paraglacial and periglacial features palaeoglaciology; Ulu are superimposed upon remnant glacial features, reflecting the post-glacial evolution of the Peninsula; James Ross Island; landscape. The study area can be broadly separated into three geomorphological sectors, Antarctic Peninsula; according to the dominant contemporary Earth-surface processes; specifically, a glacierised Antarctica southern sector, a paraglacial-dominated eastern sector, and a periglacial-dominated central/northern sector. This map provides a basis for further interdisciplinary research, and insight into the potential future landscape evolution of other parts of the Antarctic Peninsula as the climate warms. 1. Introduction Geomorphological studies are particularly impor- tant in Antarctic landscapes because they can provide Prior to the beginning of the twenty-first century, the information that is difficult to ascertain by other Antarctic Peninsula was one of the most rapidly means. For example, the use of marine geological evi- warming parts of the World (Carrivick et al., 2012; dence from the continental shelf and terrestrial lacus- Oliva et al., 2017; Turner et al., 2005, 2016; Vaughan trine records for establishing ice sheet chronologies in et al., 2003), with the north-eastern Antarctic Penin- the Antarctic Peninsula region is sometimes proble- sula being particularly susceptible to changes in matic because of a large marine reservoir effect that atmospheric and ocean temperatures (Pritchard can impede accurate radiocarbon dating (Davies et al., 2012). These changes resulted in the accelera- et al., 2012b; Ingólfsson et al., 1992; Píšková et al., tion, thinning, and recession of glaciers in the area, 2019; Pudsey et al., 2006), albeit some accurate radio- as well as the collapse of several large ice shelves carbon chronologies have been successfully estab- (Cook et al., 2005; Cook & Vaughan, 2010; Engel lished (e.g. Charman et al., 2018; Dickens et al., et al., 2012; Glasser et al., 2009; Hodgson, 2011; Pritch- 2019; Sterken et al., 2012; Watcham et al., 2011). ard et al., 2012; Seehaus et al., 2018). To improve our Other approaches have relied on cosmogenic nuclide understanding of climatic and oceanic forcing in this dating techniques or glacial geology investigations region there is a need to understand how these dra- for assessing the vertical and dynamic changes in the matic changes fit into longer-term trends and pro- ice sheet over time. However, in ice-covered areas, cesses. One way to do this is to exploit the these methods are reliant upon the location of nuna- geomorphological record to determine past glacier taks, which can only provide spatially limited, pin- extents, glacier mass balance sensitivities, and controls point data (Balco et al., 2013). Furthermore, the on ice dynamics. Furthermore, an appreciation of the inheritance of cosmogenic isotopes poses a challenge paraglacial/periglacial evolution of the Antarctic land- for accurate cosmogenic exposure dating in Antarctica scape is crucial for assessing how glacierised land- (e.g. Bentley et al., 2006). scapes across the Antarctic Peninsula will respond to The comparatively large expanse of the deglaciated future climate-induced glacial recession and deglacia- region of the Ulu Peninsula provides an opportunity tion (Lee et al., 2017; Siegert et al., 2019). to study the history of the area on a larger scale than CONTACT Stephen J. A. Jennings [email protected] Polar-Geo-Lab, Department of Geography, Faculty of Science, Masaryk University, Kotlářská 2, Brno 611 37, Czech Republic © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of Journal of Maps This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrest- ricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 126 S. J. A. JENNINGS ET AL. is possible in other areas of the Antarctic Peninsula, in sandstone beds (Crame et al., 1991; Francis et al., an area that has been extensively studied (e.g. Glasser 2006; Ineson et al., 1986). These sediments are over- et al., 2014; Johnson et al., 2011; Kaplan et al., 2020; lain by multiple horizons of subaqueous/subglacial Nývlt et al., 2014). By investigating the preserved land- hyaloclastite breccias and massive subaerial basalts of forms, the Ulu Peninsula can be treated as a case study Neogene age. The volcanic rocks forming the James for assessing landform evolution in response to future Ross Island Volcanic Group (Smellie et al., 2008) climate change. and host beds of glacigenic strata are referred to as The aim of this paper and its associated geomor- the Hobbs Glacier Formation at the boundary with phological map is to supplement the previously Cretaceous strata (Davies et al., 2013; Hambrey published maps of the Ulu Peninsula (British Ant- et al., 2008; Hambrey & Smellie, 2006; Pirrie et al., arctic Survey, 2017; Czech Geological Survey, 1997), and the Mendel Formation (2011) between 2009; Davies et al., 2013; Kaplan et al., 2020; individual volcanic sequences. The hyaloclastite and Mlčoch et al., 2020; Smellie et al., 2013; Strelin & basalt flows form prominent cliffs exposing well-pre- Malagnino, 1992), as well as other more spatially- served lava-fed deltas (Smellie et al., 2008), and the limited geomorphological investigations (e.g. Carri- volcanic rocks form prominent mesa and cinder vick et al., 2012; Kňažková et al., 2020, 2021; Lund- cone landforms (Davies et al., 2012b; Nehyba & quist et al., 1995; Strelin et al., 2006). This study Nývlt, 2014; Nelson et al., 2009; Smellie et al., 2008). comprehensively maps the geomorphology of the Spatially limited outcrops of Neogene to Quaternary northern sector of Ulu Peninsula in much greater unlithified sediments of varying origin are also present detail than has previously been achieved, utilising overlying the Cretaceous strata (Mlčoch et al., 2020). a combination of geological and geomorphological It is the geology of the Ulu Peninsula which makes approaches. As the largest deglaciated area in the it an ideal location to study the terrestrial record of the Antarctic Peninsula region, with c. 250 km2 of ice- dynamics and recession of the Last Glacial Maximum free terrain mapped in this study, the unprece- Antarctic Peninsula Ice Sheet because it is distinctly dented detail and coverage of this study allows different from that of the nearby Antarctic Peninsula the relationships between different landforms to be (Glasser et al., 2014; Kaplan et al., 2020; Nývlt et al., analysed on a more comprehensive scale, revealing 2014). Erratics composed of lithologies that are absent information about past ice dynamics, the history as bedrock on Ulu Peninsula, and therefore must have of glacier recession, and paraglacial/periglacial land- originated from the mainland
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