Characterization of a landslide-triggered debris flow at a rainforest-covered mountain region in Brazil

Debris flows represent great hazard to humans due to their high destructive power. Understanding their hydrogeomorphic dynamics is fundamental in hazard assessment studies, especially in subtropical and tropical regions where debris flows have scarcely been studied when compared to other mass-wastin...

Full description

Saved in:

Bibliographic Details
Published in:	Natural hazards (Dordrecht) Vol. 108; no. 3; pp. 3021 - 3043
Main Authors:	Cabral, Victor Carvalho, Reis, Fábio Augusto Gomes Vieira, D’Affonseca, Fernando Mazo, Lucía, Ana, dos Santos Corrêa, Claudia Vanessa, Veloso, Vinicius, Gramani, Marcelo Fischer, Ogura, Agostinho Tadashi, Lazaretti, Andrea Fregolente, Vemado, Felipe, Pereira Filho, Augusto José, dos Santos, Claudia Cristina, Lopes, Eymar Silva Sampaio, Rabaco, Lis Maria Reoni, do Carmo Giordano, Lucilia, Zarfl, Christiane
Format:	Journal Article
Language:	English
Published:	Dordrecht Springer Netherlands 01-09-2021 Springer Nature B.V
Subjects:	Catchment area Civil Engineering Debris flow Detritus Discharge Earth and Environmental Science Earth Sciences Empirical equations Environmental Management Flood peak Geomorphology Geophysics/Geodesy Geotechnical Engineering & Applied Earth Sciences Hazard assessment Hydrogeology Hydrogeomorphology Landslides Mountain regions Mountains Natural Hazards Original Paper Rain Rain gauges Rainfall Rainforests Satellite data Spatial discrimination Spatial resolution Tropical climate Tropical environment Tropical environments Velocity Brazil Serra do Mar Mass movements Shallow landslides Forensic geomorphological analysis Magnitude Bedrock rivers
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Debris flows represent great hazard to humans due to their high destructive power. Understanding their hydrogeomorphic dynamics is fundamental in hazard assessment studies, especially in subtropical and tropical regions where debris flows have scarcely been studied when compared to other mass-wasting processes. Thus, this study aims at systematically analyzing the meteorological and geomorphological factors that characterize a landslide-triggered debris flow at the Pedra Branca catchment (Serra do Mar, Brazil), to quantify the debris flow’s magnitude, peak discharge and velocity. A magnitude comparison with empirical equations (Italian Alps, Taiwan, Serra do Mar) is also conducted. The meteorological analysis is based on satellite data and rain gauge measurements, while the geomorphological characterization is based on terrestrial and aerial investigations, with high spatial resolution. The results indicate that it was a large-sized stony debris flow, with a total magnitude of 120,195 m 3 , a peak discharge of 2146.7 m 3 s −1 and a peak velocity of 26.5 m s −1 . The debris flow was triggered by a 188-mm rainfall in 3 h (maximum intensity of 128 mm h −1 ), with an estimated return period of 15 to 20 years, which, combined with the intense accumulation of on-channel debris (ca. 37,000 m 3 ), indicates that new high-magnitude debris flows in the catchment and the region are likely to occur within the next two decades. The knowledge of the potential frequency and magnitude ( F – M ) can support the creation of F – M relationships for Serra do Mar, a prerequisite for reliable hazard management and monitoring programs.
ISSN:	0921-030X 1573-0840
DOI:	10.1007/s11069-021-04811-9