Land Slide : A Key Problem in Uma Uya Project Risk Controlling
In this paper, using landslide risky zones best possible places to arrange the buildings and equipments were found in Uma Uya project. The risky zones of the project is achieved and presented. Uma Uma project is a multipurpose project. Uma Oya is a major tributary of Mahaweli Ganga originating from Nuwara Eliya. The Oya traverses Welimada and Kandaketiya in Badulla district. Its confluence with Mahaweli Ganga is just above the Rantabe reservoir. Landslides are aggravated by human activities. Activities include deforestation, cultivation and construction. Main causes can be vibrations from machinery, blasting, earthwork which alters the shape of a slope, removal of deep rooted vegetation and construction. As it can be seen from results the main risky zones are located at high levels of the site. It is clear from results that about %30 of the site zones are involved in high risky landslide. While, about %50 of zones are low risky zones and about %20 of zones are no risky zones. Thus, site mobilization in such zones is dangerous.
Landslide Morphology and Processes on Santa Cruz Island, California
An episode of unusually intense rainfall triggered over a thousand landslides on Santa Cruz Island, California, during the winter of 1977-78. These included large, deep-seated failures, composite mudflows, and hundreds of shallow soil slips. In this study, landslide occurrence is examined in relation to lithologic, pedologic, topographic, and vegetational conditions. Their effects on soil permeability, water movement patterns, and shear strength are found to be related to landslide morphology and process.
Facies and microfacies of slope deposits
Abstract This paper reviews the facies and microfacies of the main types of slope deposits. Lamination and sorting, when preserved, are good evidence for overland flow. Features due to deformation (folds, boudins, coatings and tails due to the rotation of clasts) are associated with the early stages of deformation in earth slides. Other mass-movements such as debris flows, rock avalanches, earth flows, and to a certain extent, dry grain flows may be characterised by similar microscopic facies, typically a poorly sorted, porphyric material. Porosity gives evidence for both liquefaction (debris flows) and frost-induced mass-movement (solifluction). However, this criterion is thought to be irrelevant for fossil deposits owing to the rapidity and scale of post-depositional changes (wetting and drying, freezing and thawing, bioturbation). At present, only a detailed analysis of both the macro- and micromorphological characteristics of the deposits allows an accurate identification of past slope dynamics.