Prosiectau fesul blwyddyn
Crynodeb
Characterising the structures within glaciers can give unique insight into ice motion processes. On debris-covered glaciers, traditional structural glaciological mapping is challenging because the lower glacier is hidden by the supraglacial debris layer. Here, we use high-resolution optical televiewer (OPTV) image logs from four boreholes drilled into Khumbu Glacier, Nepal, to overcome this limitation and investigate englacial structural features within a Himalayan debris-covered glacier. The OPTV logs show structural features that are up to an order of magnitude thinner than those observed at the glacier surface and reveal five structural units: (I) primary stratification of ice; (II) debris-rich planes that conform with the primary stratification; (III) water-healed crevasse traces; (IV) healed crevasse traces; and (V) steeply dipping planes of basally derived fine sediment near the glacier terminus. The OPTV logs also reveal that the primary stratification both decreases in dip with depth (by up to 56° over 20 m) and rotates with depth (by up to 100° over 20 m) towards parallelism with the proximal lateral moraine. This transformation and the presence of relict layers of basally derived sediment raised into an englacial position - possibly involving thrusting - near the glacier's now stagnant terminus reveal a previously more dynamic glacier regime.
Iaith wreiddiol | Saesneg |
---|---|
Tudalennau (o-i) | 811-822 |
Nifer y tudalennau | 12 |
Cyfnodolyn | Journal of Glaciology |
Cyfrol | 69 |
Rhif cyhoeddi | 276 |
Dyddiad ar-lein cynnar | 19 Rhag 2022 |
Dynodwyr Gwrthrych Digidol (DOIs) | |
Statws | Cyhoeddwyd - 18 Awst 2023 |
Ôl bys
Gweld gwybodaeth am bynciau ymchwil 'Internal structure of a Himalayan debris-covered glacier revealed by borehole optical televiewing'. Gyda’i gilydd, maen nhw’n ffurfio ôl bys unigryw.Setiau Data
-
Borehole optical televiewer (OPTV) logs of boreholes drilled into Khumbu Glacier, Nepal, in 2017 and 2018 as part of EverDrill research project
Hubbard, B., Miles, K. & Quincey, D. J., UK Polar Data Centre, 11 Ion 2019
Dangosydd eitem ddigidol (DOI): 10.5285/d80f5c86-89a7-46d6-8718-47e3d34ab368
Set ddata
-
Summary of instrumentation installed in boreholes drilled into Khumbu Glacier, Nepal, in 2017 and 2018 as part of EverDrill research project
Hubbard, B., Miles, K., Quincey, D. J. & Miles, E. S., UK Polar Data Centre, 09 Ion 2019
Dangosydd eitem ddigidol (DOI): 10.5285/a7f28dea-64f7-43b5-bc39-a6cfcdeefbda
Set ddata
Prosiectau
- 1 Wedi Gorffen
-
Everdrill: Accessing the interior and bed of a Himalayan debris-covered glacier to forecast future mass loss
Hubbard, B. (Prif Ymchwilydd), Quincey, D. J. (Prif Ymchwilydd) & Rowan, A. V. (Prif Ymchwilydd)
Natural Environment Research Council
01 Hyd 2016 → 31 Awst 2019
Prosiect: Ymchwil a ariannwyd yn allanol