The present research focuses on a detailed facies description and interpretation of five alluvial fans of the Qazvin Plain. Beside the tectonic activity that leads to the localization of the fans on the northern margin of the Qazvin Plain, the climate has a significant role in the occurrence of their facies. The alluvial fans are divided into three facies groups: group 1, group 2, and group 3. ...

Debris flow is an important sedimenttransport mechanism in subaerial and subaqueous environments. Its properties change almost continuously as sediment and water are added to or subtracted from it (Smith and Lowe, 1991; Vallance, 2000). In subaerial environments, debris flows are commonly diluted into hyperconcentrated flows when they encounter a streamflow (Pierson and Costa, 1987; Costa, 1988...

a numerical model for two-phase debris flows is developed in this paper, on the basis of understanding of the physical characteristics of debris flows from field investigations and experiments. employing a moving coordinate, the kinetic energy equation of gravel particles in unit volume in debris flow is developed by considering the potential energy of the particles, energy from the liquid phas...

Article history: Received 14 March 2016 Received in revised form 7 August 2016 Accepted 8 August 2016 Available online 16 August 2016 After recognition that debris flows co-occur with human activities, the next step in a hazards analysis involves estimating debris-flowprobability. Prior research published in this journal in 2010 used varnishmicrolamination (VML) dating to determine a minimum oc...

Debris flows are one of the most hazardous types of landslides in mountainous areas of western North America because they are fast moving and can occur with little warning. Field observations and existing literature indicate that three primary types of nonvolcanic debris flows affect areas of western North America (Fig. 1): 1) debris flows that mobilize from landslides (i.e., “slides” using the...

As in many areas of high relief, debris flows are an important process linkage between hillslopes and the Green River in the canyons of the eastern Uinta Mountains, yet the physical conditions that lead to debris flow initiation are unknown. A recent episode of enhanced debris-flow and wildfire activity provided an opportunity to examine the geomorphic impact of fire and the processes by which ...

Debris flows are a type of mass movement that occurs in mountain torrents. They consist of a high concentration of solid material in water that flows as a wave with a steep front. Debris flows can be considered a phenomenon intermediate between landslides and water floods. They are amongst the most hazardous natural processes in mountainous regions and may occur under different climatic conditi...

Most previous studies on the initiation mechanism of debris flows have achieved some significant results by means of traditional linear methods, statistical analyses, and qualitative and single-factor analyses. In fact, however, a large number of field observation analysis indicate that the initiation of debris flows may be a complicated nonlinear process subject to many influencing factors, wi...

This study compares documented debris flow runout distances with numerical simulations in the Yosemite Valley of California, USA, where about 15% of historical events of slope instability can be classified as debris flows and debris slides (Wieczorek and Snyder, 2004). To model debris flows in the Yosemite Valley, we selected six streams with evidence of historical debris flows; three of the de...