Do subglacial bedforms comprise a size and shape continuum?

J. Ely, C.D. Clark, M Spagnolo, C.R. Stokes, S.L. Greenwood, A.L.C. Hughs, P. Dunlop, D. Hess

Research output: Contribution to journalArticle

39 Citations (Scopus)

Abstract

Understanding the evolution of the ice-bed interface is fundamentally important for gaining insight into the dynamics of ice masses and how subglacial landforms are created. However, the formation of the suite of landforms generated at this boundary — subglacial bedforms — is a contentious issue that is yet to be fully resolved. Bedforms formed in aeolian, fluvial, and marine environments either belong to separate morphological populations or are thought to represent a continuum of forms generated by the same governing processes. For subglacial bedforms, a size and shape continuum has been hypothesised, yet it has not been fully tested. Here we analyse the largest data set of subglacial bedform size and shape measurements ever collated (96,900 bedforms). Our results show that flutes form a distinct population of narrow bedforms. However, no clear distinction was found between drumlins and megascale glacial lineations (MSGLs), which form a continuum of subglacial lineations. A continuum of subglacial ribs also exists, with no clear size or shape distinctions indicating separate populations. Furthermore, an underreported class of bedform with no clear orientation to ice flow (quasi-circular bedforms) overlaps with the ribbed and lineation continua and typically occurs in spatial transition zones between the two, potentially merging these three bedform types into a larger continuum.
LanguageEnglish
Pages108-119
Number of pages12
JournalGeomorphology
Volume257
Early online date6 Jan 2016
DOIs
Publication statusPublished - 15 Mar 2016

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bedform
lineation
landform
ice
drumlin
ice flow
transition zone
marine environment

Keywords

  • subglacial bedforms
  • drumlins
  • ribbed moraine
  • flutes

Cite this

Ely, J., Clark, C. D., Spagnolo, M., Stokes, C. R., Greenwood, S. L., Hughs, A. L. C., ... Hess, D. (2016). Do subglacial bedforms comprise a size and shape continuum? 257, 108-119. https://doi.org/10.1016/j.geomorph.2016.01.001
Ely, J. ; Clark, C.D. ; Spagnolo, M ; Stokes, C.R. ; Greenwood, S.L. ; Hughs, A.L.C. ; Dunlop, P. ; Hess, D. / Do subglacial bedforms comprise a size and shape continuum?. 2016 ; Vol. 257. pp. 108-119.
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title = "Do subglacial bedforms comprise a size and shape continuum?",
abstract = "Understanding the evolution of the ice-bed interface is fundamentally important for gaining insight into the dynamics of ice masses and how subglacial landforms are created. However, the formation of the suite of landforms generated at this boundary — subglacial bedforms — is a contentious issue that is yet to be fully resolved. Bedforms formed in aeolian, fluvial, and marine environments either belong to separate morphological populations or are thought to represent a continuum of forms generated by the same governing processes. For subglacial bedforms, a size and shape continuum has been hypothesised, yet it has not been fully tested. Here we analyse the largest data set of subglacial bedform size and shape measurements ever collated (96,900 bedforms). Our results show that flutes form a distinct population of narrow bedforms. However, no clear distinction was found between drumlins and megascale glacial lineations (MSGLs), which form a continuum of subglacial lineations. A continuum of subglacial ribs also exists, with no clear size or shape distinctions indicating separate populations. Furthermore, an underreported class of bedform with no clear orientation to ice flow (quasi-circular bedforms) overlaps with the ribbed and lineation continua and typically occurs in spatial transition zones between the two, potentially merging these three bedform types into a larger continuum.",
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author = "J. Ely and C.D. Clark and M Spagnolo and C.R. Stokes and S.L. Greenwood and A.L.C. Hughs and P. Dunlop and D. Hess",
note = "Reference text: Aario, R., 1977. Classification and terminology of morainic landforms in Finland. Boreas 6(2), 87-100. Allen, J.R.L., 1968. The nature and origin of bed-form hierarchies. Sedimentology 10(3), 161-182. Alley, R.B., Blankenship, D.D., Bentley, C.R., Rooney, S., 1986. Deformation of till beneath ice stream B, West Antarctica. Nature 322, 57-59. Amos, C.L., King, E.L., 1984. Bedforms of the Canadian eastern seaboard: a comparison with global occurrences. Marine Geology 57(1), 167-208. Anderson, J.B., Fretwell, L.O., 2008. Geomorphology of the onset area of a paleo‐ice stream, Marguerite Bay, Antarctic Peninsula. Earth Surface Processes and Landforms 33(4), 503-512. Andreassen, K., Laberg, J.S., Vorren, T.O., 2008. Seafloor geomorphology of the SW Barents Sea and its glaci-dynamic implications. Geomorphology 97(1), 157-177. Ashley, G.M., 1990. Classification of large-scale subaqueous bedforms: a new look at an old problem-SEPM bedforms and bedding structures. Journal of Sedimentary Research 60(1), 160-172. Aylsworth, J.M., W.W. Shilts., 1989. Bedforms of the Keewatin ice sheet, Canada. Sedimentary Geology 62(2), 407-428. Bouchard, M.A., 1989. Subglacial landforms and deposits in central and northern Quebec, Canada, with emphasis on Rogen moraines. Sedimentary Geology 62(2), 293-308. Boulton, G.S., 1976. The origin of glacially fluted surfaces--observations and theory. Journal of Glaciology 17, 287-309. Boulton, G.S. 1987. A theory of drumlin formation by subglacial sediment deformation. In Menzies, J. and Rose, J. (Eds.) Drumlin Symposium, Balkema, Rotterdamn, 25-80. Boyce, J.I., Eyles, N., 1991. Drumlins carved by deforming till streams below the Laurentide ice sheet. Geology 19(8), 787-790. Briner, J.P., 2007. Supporting evidence from the New York drumlin field that elongate subglacial bedforms indicate fast ice flow. Boreas 36(2), 143-147. Brown, V.H., Stokes, C.R., O'Cofaigh, C., 2011. The glacial geomorphology of the North-West sector of the Laurentide Ice Sheet. Journal of Maps 7(1), 409-428. Carl, J.D., 1978. Ribbed moraine–drumlin transition belt, St. Lawrence Valley, New York. Geology 6(9), 562-566. Carling, P.A., 1999. Subaqueous gravel dunes. Journal of Sedimentary Research 69(3). Clark, C.D., 1993. Mega‐scale glacial lineations and cross‐cutting ice‐flow landforms. Earth Surface Processes and Landforms 18(1), 1-29. Clark, C.D., 1994. Large-scale ice-moulding: a discussion of genesis and glaciological significance. Sedimentary Geology 91(1), 253-268. Clark, C.D., 1999. Glaciodynamic context of subglacial bedform generation and preservation. Annals of Glaciology 28(1), 23-32. Clark, C.D., Hughes, A.L., Greenwood, S.L., Spagnolo, M., Ng, F.S., 2009. Size and shape characteristics of drumlins, derived from a large sample, and associated scaling laws. Quaternary Science Reviews 28(7), 677-692. Costello, W.R., Southard, J.B., 1981., Flume experiments on lower-flow-regime bed forms in coarse sand. Journal of Sedimentary Research 51(3). Cutts, J.A., Smith, R.S.U., 1973. Eolian deposits and dunes on Mars. Journal of Geophysical Research 78(20), 4139-4154. Dardis, G.F., McCabe, A.M., Mitchell, W.I., 1984. Characteristics and origins of lee‐side stratification sequences in late pleistocene drumlins, northern Ireland. Earth Surface Processes and Landforms 9(5), 409-424. Dionne, J.C. 1987., Tadpole rock (rock drumlin): A glacial stream moulded form. In: Menzies, J. and Rose, J. (Eds): Drumlin Symposium. Balkema. Rotterdam. 149-159. Dowling, T.P.F., Spagnolo, M., M{\"o}ller, P., 2015. Morphometry and core type of streamlined bedforms in southern Sweden from high resolution LiDAR. Geomorphology 236, 54-63. Dunlop, P., Clark, C.D., 2006a. Distribution of ribbed moraine in the Lac Naococane Region, Central Qu{\'e}bec, Canada. Journal of Maps 2(1), 59-70. Dunlop, P., Clark, C.D., 2006b. 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Ely, J, Clark, CD, Spagnolo, M, Stokes, CR, Greenwood, SL, Hughs, ALC, Dunlop, P & Hess, D 2016, 'Do subglacial bedforms comprise a size and shape continuum?', vol. 257, pp. 108-119. https://doi.org/10.1016/j.geomorph.2016.01.001

Do subglacial bedforms comprise a size and shape continuum? / Ely, J.; Clark, C.D.; Spagnolo, M; Stokes, C.R.; Greenwood, S.L.; Hughs, A.L.C.; Dunlop, P.; Hess, D.

Vol. 257, 15.03.2016, p. 108-119.

Research output: Contribution to journalArticle

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T1 - Do subglacial bedforms comprise a size and shape continuum?

AU - Ely, J.

AU - Clark, C.D.

AU - Spagnolo, M

AU - Stokes, C.R.

AU - Greenwood, S.L.

AU - Hughs, A.L.C.

AU - Dunlop, P.

AU - Hess, D.

N1 - Reference text: Aario, R., 1977. Classification and terminology of morainic landforms in Finland. Boreas 6(2), 87-100. Allen, J.R.L., 1968. The nature and origin of bed-form hierarchies. Sedimentology 10(3), 161-182. Alley, R.B., Blankenship, D.D., Bentley, C.R., Rooney, S., 1986. Deformation of till beneath ice stream B, West Antarctica. Nature 322, 57-59. Amos, C.L., King, E.L., 1984. Bedforms of the Canadian eastern seaboard: a comparison with global occurrences. Marine Geology 57(1), 167-208. Anderson, J.B., Fretwell, L.O., 2008. Geomorphology of the onset area of a paleo‐ice stream, Marguerite Bay, Antarctic Peninsula. Earth Surface Processes and Landforms 33(4), 503-512. Andreassen, K., Laberg, J.S., Vorren, T.O., 2008. Seafloor geomorphology of the SW Barents Sea and its glaci-dynamic implications. Geomorphology 97(1), 157-177. Ashley, G.M., 1990. Classification of large-scale subaqueous bedforms: a new look at an old problem-SEPM bedforms and bedding structures. Journal of Sedimentary Research 60(1), 160-172. Aylsworth, J.M., W.W. Shilts., 1989. Bedforms of the Keewatin ice sheet, Canada. Sedimentary Geology 62(2), 407-428. Bouchard, M.A., 1989. Subglacial landforms and deposits in central and northern Quebec, Canada, with emphasis on Rogen moraines. Sedimentary Geology 62(2), 293-308. Boulton, G.S., 1976. The origin of glacially fluted surfaces--observations and theory. Journal of Glaciology 17, 287-309. Boulton, G.S. 1987. A theory of drumlin formation by subglacial sediment deformation. In Menzies, J. and Rose, J. (Eds.) Drumlin Symposium, Balkema, Rotterdamn, 25-80. Boyce, J.I., Eyles, N., 1991. Drumlins carved by deforming till streams below the Laurentide ice sheet. Geology 19(8), 787-790. Briner, J.P., 2007. Supporting evidence from the New York drumlin field that elongate subglacial bedforms indicate fast ice flow. Boreas 36(2), 143-147. Brown, V.H., Stokes, C.R., O'Cofaigh, C., 2011. The glacial geomorphology of the North-West sector of the Laurentide Ice Sheet. Journal of Maps 7(1), 409-428. Carl, J.D., 1978. Ribbed moraine–drumlin transition belt, St. Lawrence Valley, New York. Geology 6(9), 562-566. Carling, P.A., 1999. Subaqueous gravel dunes. Journal of Sedimentary Research 69(3). Clark, C.D., 1993. Mega‐scale glacial lineations and cross‐cutting ice‐flow landforms. Earth Surface Processes and Landforms 18(1), 1-29. Clark, C.D., 1994. Large-scale ice-moulding: a discussion of genesis and glaciological significance. Sedimentary Geology 91(1), 253-268. Clark, C.D., 1999. Glaciodynamic context of subglacial bedform generation and preservation. Annals of Glaciology 28(1), 23-32. Clark, C.D., Hughes, A.L., Greenwood, S.L., Spagnolo, M., Ng, F.S., 2009. Size and shape characteristics of drumlins, derived from a large sample, and associated scaling laws. Quaternary Science Reviews 28(7), 677-692. Costello, W.R., Southard, J.B., 1981., Flume experiments on lower-flow-regime bed forms in coarse sand. Journal of Sedimentary Research 51(3). Cutts, J.A., Smith, R.S.U., 1973. Eolian deposits and dunes on Mars. Journal of Geophysical Research 78(20), 4139-4154. Dardis, G.F., McCabe, A.M., Mitchell, W.I., 1984. Characteristics and origins of lee‐side stratification sequences in late pleistocene drumlins, northern Ireland. Earth Surface Processes and Landforms 9(5), 409-424. Dionne, J.C. 1987., Tadpole rock (rock drumlin): A glacial stream moulded form. In: Menzies, J. and Rose, J. (Eds): Drumlin Symposium. Balkema. Rotterdam. 149-159. Dowling, T.P.F., Spagnolo, M., Möller, P., 2015. Morphometry and core type of streamlined bedforms in southern Sweden from high resolution LiDAR. Geomorphology 236, 54-63. Dunlop, P., Clark, C.D., 2006a. Distribution of ribbed moraine in the Lac Naococane Region, Central Québec, Canada. Journal of Maps 2(1), 59-70. Dunlop, P., Clark, C.D., 2006b. 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PY - 2016/3/15

Y1 - 2016/3/15

N2 - Understanding the evolution of the ice-bed interface is fundamentally important for gaining insight into the dynamics of ice masses and how subglacial landforms are created. However, the formation of the suite of landforms generated at this boundary — subglacial bedforms — is a contentious issue that is yet to be fully resolved. Bedforms formed in aeolian, fluvial, and marine environments either belong to separate morphological populations or are thought to represent a continuum of forms generated by the same governing processes. For subglacial bedforms, a size and shape continuum has been hypothesised, yet it has not been fully tested. Here we analyse the largest data set of subglacial bedform size and shape measurements ever collated (96,900 bedforms). Our results show that flutes form a distinct population of narrow bedforms. However, no clear distinction was found between drumlins and megascale glacial lineations (MSGLs), which form a continuum of subglacial lineations. A continuum of subglacial ribs also exists, with no clear size or shape distinctions indicating separate populations. Furthermore, an underreported class of bedform with no clear orientation to ice flow (quasi-circular bedforms) overlaps with the ribbed and lineation continua and typically occurs in spatial transition zones between the two, potentially merging these three bedform types into a larger continuum.

AB - Understanding the evolution of the ice-bed interface is fundamentally important for gaining insight into the dynamics of ice masses and how subglacial landforms are created. However, the formation of the suite of landforms generated at this boundary — subglacial bedforms — is a contentious issue that is yet to be fully resolved. Bedforms formed in aeolian, fluvial, and marine environments either belong to separate morphological populations or are thought to represent a continuum of forms generated by the same governing processes. For subglacial bedforms, a size and shape continuum has been hypothesised, yet it has not been fully tested. Here we analyse the largest data set of subglacial bedform size and shape measurements ever collated (96,900 bedforms). Our results show that flutes form a distinct population of narrow bedforms. However, no clear distinction was found between drumlins and megascale glacial lineations (MSGLs), which form a continuum of subglacial lineations. A continuum of subglacial ribs also exists, with no clear size or shape distinctions indicating separate populations. Furthermore, an underreported class of bedform with no clear orientation to ice flow (quasi-circular bedforms) overlaps with the ribbed and lineation continua and typically occurs in spatial transition zones between the two, potentially merging these three bedform types into a larger continuum.

KW - subglacial bedforms

KW - drumlins

KW - ribbed moraine

KW - flutes

U2 - 10.1016/j.geomorph.2016.01.001

DO - 10.1016/j.geomorph.2016.01.001

M3 - Article

VL - 257

SP - 108

EP - 119

ER -

Ely J, Clark CD, Spagnolo M, Stokes CR, Greenwood SL, Hughs ALC et al. Do subglacial bedforms comprise a size and shape continuum? 2016 Mar 15;257:108-119. https://doi.org/10.1016/j.geomorph.2016.01.001