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1.
Abstract

Large debris flows in steep-sloped ravines debouching to the Rimac River, in metropolitan Lima (Peruvian capital), have resulted in considerable loss of life and property adversely impacting communities in the region. Temporal, spatial and volumetric features of debris flows are difficult to predict, and it is of utmost importance that achievable management solutions are found to reduce the impact of these catastrophic events. The emotional and economic toll of these debris flows on this increasingly densely populated capital city in South America is devastating where communities must live in such inadequate and dangerous conditions. To address this problem, the application of advanced Japanese technology, Sustainable Actions Basin Orientation (SABO), has been investigated using a geomorphological modelling to develop an implementation plan. Rayos de Sol stream basin in Chosica, was selected as a pilot to develop the proposal, as it is considered high risk due to the presence of ancient debris flows and recent flows in 2012, 2015 and 2017. The recurrence of debris flows in this location has resulted in numerous deaths and catastrophic property losses. This study combines geologic and geomorphic mapping and hydraulic and landform evolution numerical modelling. The implementation of a SABO Master Plan based on the multidisciplinary assessment hazard scenarios, will allow the implementation of feasible mitigation actions. The SABO technology has been applied successfully in Japan and other countries in areas with steep short slopes, similar to the conditions surrounding the Peruvian capital. Results from this study will be presented to the Peruvian Government as part of an action plan to manage debris-flow impact.
  1. KEY POINTS
  2. High-risk mass slope failure is linked to poor urban planning in urban developing regions of Lima the capital of Peru.

  3. A multidisciplinary study including geotechnical and hydrological analysis, engineering design, and socio-economic research is required to implement a SABO Master Plan, and this basin is pilot study basin.

  4. At the present time, a maintenance programme for existing hydraulic structures should be implemented, and a flood risk management plan developed may propose the relocation of some communities and infrastructure.

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2.
Corundum-containing and corundum-free plagioclasites localized in chromite-bearing ultramafites of the Rai-Iz Massif were explored for the composition and age. The composition of rock-forming minerals was studied, and the geochemical characteristics of the rocks were ascertained. The isotope age of plagioclasites determined by zircons using the U–Pb mode with a SHRIMP II device was equal to 398 ± 3 Ma. The age found conformed to the boundary on most of the Rai-Iz Massif took place against the background of a starting powerful collision, which caused the formation of the chromium mineralization of a high-chromic type, as well as the separation of a series of essentially plagioclase rocks of ruby mineralization at the discharge zones of the vein series.  相似文献   
3.
Geomagnetism and Aeronomy - The results of experimental studies of the characteristics of low-frequency (LF) radiation excited by the impact of two frequency-shifted, unmodulated pump waves emitted...  相似文献   
4.
Astronomy Reports - The observed characteristics of the spectral and photometric variability of SS 433 are discussed based on the data for 2018–2021 and compared with earlier results. The...  相似文献   
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Doklady Earth Sciences - The change in the distribution of Cu compounds by size fractions with an increase in its concentration in noncontaminated surface waters has been studied experimentally. It...  相似文献   
6.
Joseph  Jeevan  Rakshith  Shetty  Singh  D. N.  Tang  C. S. 《Acta Geotechnica》2022,17(9):3855-3865
Acta Geotechnica - Numerous applications of hydraulic conductivity of porous media (e.g., soils, clay liners, rocks, concrete, ceramic filters, etc.) in their unsaturated state are well established...  相似文献   
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Natural Resources Research - Oil shale impurities prevent its direct usage as a source of energy. Removing or reducing of these impurities before retorting can reduce the cost of oil shale...  相似文献   
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