Size, shape and spatial arrangement of mega-scale glacial lineations from a large and diverse dataset

Simple item page
dc.citation.firstpage1432en_US
dc.citation.issueNumber11en_US
dc.citation.journalTitleEarth Surface Processes and Landformsen_US
dc.citation.lastpage1448en_US
dc.citation.volumeNumber39en_US
dc.contributor.authorSpagnolo, Matteoen_US
dc.contributor.authorClark, Chris D.en_US
dc.contributor.authorEly, Jeremy C.en_US
dc.contributor.authorStokes, Chris R.en_US
dc.contributor.authorAnderson, John B.en_US
dc.contributor.authorAndreassen, Karinen_US
dc.contributor.authorGraham, Alastair G.C.en_US
dc.contributor.authorKing, Edward C.en_US
dc.date.accessioned2016-01-28T22:50:35Zen_US
dc.date.available2016-01-28T22:50:35Zen_US
dc.date.issued2014en_US
dc.description.abstractMega-scale glacial lineations (MSGLs) are a characteristic landform on ice stream beds. Solving the puzzle of their formation is key to understanding how ice interacts with its bed and how this, in turn, influences the dynamics of ice streams. However, a comprehensive and detailed characterization of this landform's size, shape and spatial arrangement, which might serve to test and refine formational theories, is largely lacking. This paper presents a detailed morphometric analysis and comparison of 4043 MSGLs from eight palaeo-ice stream settings: three offshore (Norway and Antarctica), four onshore (Canada), and one from under a modern ice stream in West Antarctica. The length of MSGLs is lower than previously suggested (mode 1000–2000 m; median 2892 m), and they initiate and terminate at various locations on an ice stream bed. Their spatial arrangement reveals a pattern that is characterized by an exceptional parallel conformity (80% of all mapped MSGLs have an azimuth within 5° from the mean values), and a fairly constant lateral spacing (mode 200–300 m; median 330 m), which we interpret as an indication that MSGLs are a spatially self-organized phenomenon. Results show that size, shape and spatial arrangement of MSGLs are consistent both within and also generally between different ice stream beds. We suggest this results from a common mechanism of formation, which is largely insensitive to local factors. Although the elongation of MSGLs (mode 6–8; median 12.2) is typically higher than features described as drumlins, these values and those of their width (mode 100–200 m; median 268 m) overlap, which suggests the two landforms are part of a morphological continuum and may share a similar origin. We compare their morphometry with explicit predictions made by the groove-ploughing and rilling instability theories of MSGL formation. Although the latter was most compatible, neither is fully supported by observations.en_US
dc.identifier.citationSpagnolo, Matteo, Clark, Chris D., Ely, Jeremy C., et al.. "Size, shape and spatial arrangement of mega-scale glacial lineations from a large and diverse dataset." <i>Earth Surface Processes and Landforms,</i> 39, no. 11 (2014) Wiley: 1432-1448. http://dx.doi.org/10.1002/esp.3532.en_US
dc.identifier.doihttp://dx.doi.org/10.1002/esp.3532en_US
dc.identifier.urihttps://hdl.handle.net/1911/88242en_US
dc.language.isoengen_US
dc.publisherWileyen_US
dc.rightsThis is an open access article under the terms of the Creative Commons Attribution�License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.en_US
dc.rights.urihttp://creativecommons.org/licenses/by/3.0/en_US
dc.subject.keywordMSGLen_US
dc.subject.keywordglacial bedformen_US
dc.subject.keywordice streamen_US
dc.subject.keywordmorphometryen_US
dc.titleSize, shape and spatial arrangement of mega-scale glacial lineations from a large and diverse dataseten_US
dc.typeJournal articleen_US
dc.type.dcmiTexten_US
dc.type.publicationpublisher versionen_US
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Spagnolo_et_al-2014.pdf
Size:
20.84 MB
Format:
Adobe Portable Document Format
Download
Collections
Faculty Publications
Earth, Environmental and Planetary Sciences Publications