Abstract
Alluvial fans are large-scale depositional structures commonly found at the base of mountain ranges. They are relatively soil-rich compared to the rocky terrains, or catchment areas, from which their material originates. When frequented by debris flows (massive, muddy, rocky flows) they contribute significantly to local hazards as they carry focused, collisional, fast-moving materials across alluvial fans, unpredictable in size, speed, and direction. We research how fine particle content in debris flows correlates with directional changes, i.e., debris flow avulsions. Toward this, we analyzed field data from two neighboring alluvial fans in the White Mountains (California, USA) that exhibit dramatically different topographies despite their proximity and associated similar long-term climates. Informed by these measurements, we performed long-term and incremental alluvial fan experiments built by debris flows with systematically-varied fine particle content. We found that (1) decreasing fine particle content increases the variability of fan slopes and associated channelization dynamics, and (2) for all mixtures longer-term continuous alluvial fan experiments form more complex surface channelizations than repeated flows for the same total time, indicating the importance of both particle sizes and timescales on alluvial fan surface morphology.
| Original language | English (US) |
|---|---|
| Article number | 21730 |
| Journal | Scientific reports |
| Volume | 12 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2022 |
Bibliographical note
Funding Information:The authors are grateful for Hervé Capart and Alex Densmore for the valuable inspiration and discussion. We also thank Richard Christopher in particular and the St. Anthony Falls Laboratory research staff for generous advice and assistance in the experimental construction, especially noteworthy during limited-access CoVid19 situation. The research was supported by: the Young Scholar Fellowship Program by Ministry of Science and Technology (MOST) in Taiwan, under Grant MOST110-2636-M-005-001; the Dragon Gate Program by MOST in Taiwan, under Grant MOST108-2911-I-002-564. We also gratefully acknowledge; the National Science Foundation (NSF) under grant numbers EAR-1451957 and EAR-2127476, and the Department of State through the International Institute of Education, Global Innovation Initiative.
Funding Information:
The authors are grateful for Hervé Capart and Alex Densmore for the valuable inspiration and discussion. We also thank Richard Christopher in particular and the St. Anthony Falls Laboratory research staff for generous advice and assistance in the experimental construction, especially noteworthy during limited-access CoVid19 situation. The research was supported by: the Young Scholar Fellowship Program by Ministry of Science and Technology (MOST) in Taiwan, under Grant MOST110-2636-M-005-001; the Dragon Gate Program by MOST in Taiwan, under Grant MOST108-2911-I-002-564. We also gratefully acknowledge; the National Science Foundation (NSF) under grant numbers EAR-1451957 and EAR-2127476, and the Department of State through the International Institute of Education, Global Innovation Initiative.
Publisher Copyright:
© 2022, The Author(s).
PubMed: MeSH publication types
- Journal Article
- Research Support, U.S. Gov't, Non-P.H.S.
- Research Support, Non-U.S. Gov't