| Abstract: | We examine rockfall susceptibility of folded strata in the Sevier fold-thrust belt exposed in American Fork Canyon in north-central Utah. Large-scale geologic mapping, talus production data, rock-mass-quality measurements, and historical rockfall data indicate that rockfall susceptibility is correlated with limb dip and curvature of the folded, cliff-forming Mississippian limestones. On fold limbs, rockfall susceptibility increases as dip increases. This relation is controlled by several factors, including an increase in adverse dip conditions and apertures of discontinuities, and shearing by flexural slip during folding that has reduced the friction angles of discontinuities by smoothing surface asperities. Susceptibility is greater in fold hinge zones than on adjacent limbs primarily because there are greater numbers of discontinuities in hinge zones. We speculate that susceptibility increases in hinge zones as fold curvature becomes tighter. |
| Genre: | Article |
| ProdID: | 70032022 |
| Citation Author: | Coe, J. A.; Harp, E. L. |
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| Citation End Page: | 14 |
| Citation Issue: | 1 |
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| Citation Language: | English |
| Citation Larger Work Title: | Natural Hazards and Earth System Science |
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| Citation Number Of Pages: | 14 |
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| Citation Publisher: | European Geosciences Union |
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| Citation Search Results Text: | Influence of tectonic folding on rockfall susceptibility, American Fork Canyon, Utah, USA; 2007; Article; Journal; Natural Hazards and Earth System Science; Coe, J. A.; Harp, E. L. |
| Citation Start Page: | 1 |
| Citation Volume: | 7 |
| Citation Year: | 2007 |
| Type: | citation/reference |
| Text: | Influence of tectonic folding on rockfall susceptibility, American Fork Canyon, Utah, USA; 2007; Article; Journal; Natural Hazards and Earth System Science; Coe, J. A.; Harp, E. L. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| URL (DIGITAL OBJECT IDENTIFIER): | http://dx.doi.org/10.5194/nhess-7-1-2007 |
| Date Other: | Mon, 1 Jan 2007 00:00 -0600 |
| Publisher: | European Geosciences Union |
