Till Fabric and Deformational Structures in Drumlins Near Waukesha, Wisconsin, U.S.A.
Abstract Deep gravel-pit exposures reveal the distribution and structure of till and underlying sand and gravel in drumlins near Waukesha, Wisconsin. The subglacial sediment is interpreted to have moved laterally into the drumlin sites because the till thickens from the margin to the core of the dru...
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Language: | English |
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Cambridge University Press (CUP)
1985
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Online Access: | http://dx.doi.org/10.1017/s0022143000006535 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000006535 |
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crcambridgeupr:10.1017/s0022143000006535 2024-04-28T08:26:47+00:00 Till Fabric and Deformational Structures in Drumlins Near Waukesha, Wisconsin, U.S.A. Stanford, Scott D. Mickelson, David M. 1985 http://dx.doi.org/10.1017/s0022143000006535 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000006535 en eng Cambridge University Press (CUP) Journal of Glaciology volume 31, issue 109, page 220-228 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 1985 crcambridgeupr https://doi.org/10.1017/s0022143000006535 2024-04-09T06:55:47Z Abstract Deep gravel-pit exposures reveal the distribution and structure of till and underlying sand and gravel in drumlins near Waukesha, Wisconsin. The subglacial sediment is interpreted to have moved laterally into the drumlin sites because the till thickens from the margin to the core of the drumlins, the stone orientation in the till is perpendicular and oblique to ice flow on the drumlin margins, and recumbent isoclinal folds occur in sand on the drumlin margins with axes parallel to the drumlin axes. The resulting accumulations of sediment presented obstacles to ice flow and were streamlined into the minimum-drag drumlin shape by erosion on the margins and by remolding of material in the core of the drumlins. These drumlin nuclei may have formed at spots where there was low effective stress on the bed. The subglacial sediment became mobile as a result of high pore pressure that may have developed as ground water and subglacial melt water were trapped behind a frozen bed at the ice margin. Under certain conditions, however, lateral sediment flow might also have occurred when the sediment was frozen. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press Journal of Glaciology 31 109 220 228 |
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Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Stanford, Scott D. Mickelson, David M. Till Fabric and Deformational Structures in Drumlins Near Waukesha, Wisconsin, U.S.A. |
topic_facet |
Earth-Surface Processes |
description |
Abstract Deep gravel-pit exposures reveal the distribution and structure of till and underlying sand and gravel in drumlins near Waukesha, Wisconsin. The subglacial sediment is interpreted to have moved laterally into the drumlin sites because the till thickens from the margin to the core of the drumlins, the stone orientation in the till is perpendicular and oblique to ice flow on the drumlin margins, and recumbent isoclinal folds occur in sand on the drumlin margins with axes parallel to the drumlin axes. The resulting accumulations of sediment presented obstacles to ice flow and were streamlined into the minimum-drag drumlin shape by erosion on the margins and by remolding of material in the core of the drumlins. These drumlin nuclei may have formed at spots where there was low effective stress on the bed. The subglacial sediment became mobile as a result of high pore pressure that may have developed as ground water and subglacial melt water were trapped behind a frozen bed at the ice margin. Under certain conditions, however, lateral sediment flow might also have occurred when the sediment was frozen. |
format |
Article in Journal/Newspaper |
author |
Stanford, Scott D. Mickelson, David M. |
author_facet |
Stanford, Scott D. Mickelson, David M. |
author_sort |
Stanford, Scott D. |
title |
Till Fabric and Deformational Structures in Drumlins Near Waukesha, Wisconsin, U.S.A. |
title_short |
Till Fabric and Deformational Structures in Drumlins Near Waukesha, Wisconsin, U.S.A. |
title_full |
Till Fabric and Deformational Structures in Drumlins Near Waukesha, Wisconsin, U.S.A. |
title_fullStr |
Till Fabric and Deformational Structures in Drumlins Near Waukesha, Wisconsin, U.S.A. |
title_full_unstemmed |
Till Fabric and Deformational Structures in Drumlins Near Waukesha, Wisconsin, U.S.A. |
title_sort |
till fabric and deformational structures in drumlins near waukesha, wisconsin, u.s.a. |
publisher |
Cambridge University Press (CUP) |
publishDate |
1985 |
url |
http://dx.doi.org/10.1017/s0022143000006535 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000006535 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 31, issue 109, page 220-228 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000006535 |
container_title |
Journal of Glaciology |
container_volume |
31 |
container_issue |
109 |
container_start_page |
220 |
op_container_end_page |
228 |
_version_ |
1797586032135241728 |