Debris flows

By trapping the sediment from used alpine waters, reservoirs reduce the transport of suspended load to residual flow reaches. In these sections with a reduced channel flow, the tractive force and shear stress is drastically reduced. This additionally reduces the bed load transport, which may then result in solid matter originating from unaffected tributary streams remaiiung in the main channel, thus significantly increasing the debris-flow hazard for episodic high water discharge [36]. 

Pudasaini, S.P. and Hutter, K. (2003) Granular Avalanche Model in Arbitrarily Curved and Twisted Mountain Terrain A Basis for Extension to Debris Flow. In Dieter Ricken-mann and Cheng-lung Chen (Eds.) Debris-Flow Hazards Mitigation Mechanics, Prediction and Assessment, 1, 491-502, Millpress. 

The distribution of sediment masses in the dip slope passages suggest a debris flow that swept down the passage under completely pipe-full conditions. Recesses and side passages served to break the dynamics of the flow and thus trap localized masses of sediment, it is suspected, although not proven, that the initiation and transport of the diamicton flows was related to climatic conditions much wetter than presently occur in this part of Virginia. 

LONGVIEW FUEL SPECIFICATION SUMMARY Debris Flow... 

Terrigenous sediments, i.e. elastics consisting of material eroded from the land surface, are not only understood as nearshore shallow-water deposits on the shelf seas, but also comprise the deltaic foreset beds of continental margins, slump deposits at continental slopes produced by gravity transport, and the terrigenous-detrital shelf sediments redistributed into the deep sea by the activity of debris flows and turbidity currents. 

Alluvial fans cut by tectonic faults can also yield information on the frequency of earthquakes. An offset debris flow fan in Owens Valley (California) was dated with °Be by Bierman et al. (1995). Based on boulder ages from different parts of the flow and the record of three faulting events, the authors deduced earthquake recurrence intervals of 5800-8000 years for that location. Zreda and Noller (1998) measured C1 in a bedrock fault scarp at Hebgen Lake (Montana) and were able to extract the ages of six prehistoric... 

Multiple Mine debris flow, Slope cutting,... 

Mountainous region Landslide, collapse, mountain cracking, debris flow, failings dam failure, water loss and soil erosion, water and soil pollution... 

Once limited movement occurs the sediment becomes entrained in water and a gravity flow occurs. This movement can be described as either a laminar viscoplastic or debris flow. 

The Orksdalsfjord slide started at point A then occurred at point B. After 7 minutes a third slide occurred at point C and at approximately the same time a submarine cable Cl was cut by a debris flow from the slides (Figure 11.3). A second cable C2 went out of service approximately 2 h after the initial occurrence of slide A. The slides were attributed to an earthquake in e Scottish Hebrides. The failure of cable C2 was attributed to the loss of support in the sediment underlying the cable by liquefaction. It was not attributed to a... 

Debris flow (i.e., flow slide) rapid downward movement of predominantly unconsolidated and incoherent earth and debris in which the mass does not show backward rotation but slides or rolls forward... 

The masses involved in a slide or slump behave in a variety of ways after the initiation of failure. The soil mass behavior may range from slow creep movements, to rapid debris flows, and dilute turbidity currents. Middleton and Hampton (1976) have discussed the evolution of different t) es of flows, and have suggested a classification based on concentration and time and/or space. These various types of flow slides are given in the following list arranged from low to high concentration of particles ... 

Johnson (1970) analyzed subaerial debris flows by means of a steady-state Bingham model (plastic-viscous model with soil yield resistance, k, and linear viscosity, r ). In Johnson s model the shear stress (t ) resisting displacement is related to the velocity of movement (ra ) in the following expression ... 

Akou, A.E. 1984. Subaqueous debris flow deposits in Baffin Bay. Geo-Marine Letters, 4(2) 83-90. 

Simm, R.W., and Kidd, R.B. 1984. Submarine debris flow deposits detected by large-range side-scan sonar 1000 km from source. Geo-Marine Letters, 3 13-16. 

De Blasio, F.V., Elverhoi, A.E., Engvik, L.E., Issler, D., Ganer, R, and Harbitz, C.E. 2006. Understanding the high mobility of subaqueous debris flows. Norwegian Journal of Geology, 86 275-284. 

Hampton, M.A. 1972. The role of subaqueous debris flow in generating turbidity currents. Journal of Sedimentary Petrology, 42(4) 775-993. 

Pipeline networks that resnlt in complex reqniranents for inspection solutions (pressure/ temperature/debris/flow conditious)... 

There are two broad causes of mass wasting. One is a sudden failure of the slope sending loosened debris sliding, rolling, falling or slumping down hill and the other is a process called sediment flow where the debris flows down the slope mixed with water or air. Vames (1978) further classified landslides by the type of movement and type of material involved as shown in Table 2.14. 

Flows Rock flow Debris flow Earth flow... 

The Glasgow Formation consists primarily of volcanic breccia which reaches a thickness of 2,5(X) m at the type locality on Mt. Glasgow (71°08 S, 162°55 E). The composition of the volcanic rocks ranges from basalt to andesite but does include rhyolites. The volcanic breccias grade into debris flows and tuffaceous sediment of the Molar Formation. The presence of pillow basalt and marine fossils indicates that the eruptions occurred primarily in a subaqueous and marine environment The volcanic rocks were altered by seawater to form spUites and keratophyres composed of quartz, albite, chlorite, epidote, actinolite, and varying amounts of caldte and leucoxene (Stump 1995). 

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