Several landslides and floods were triggered by unprecedented, incessant heavy monsoon rainfall from 4 August 2019 to 8 August 2019, along the northern slopes, at Kavalappara, in the Malappuram district and Puthumala, in the Wayanad district of Kerala, India. The geological and geomorphological field settings were analyzed within the sub-basin wide catchment areas, for a preliminary evaluation of the causative factors of the landslides. This paper provides insights into the causative factors of landslides, together with suggestions on appropriate land use planning and deployment of real-time flood and landslide monitoring systems, besides building an adaptable community resilience model in high landslide-prone areas. The structurally disturbed weakened bedrocks and generally incompetent residual alteration products, exacerbated by nonchalant human interventions, reduction of cohesive strength, on super-saturation of underlying earth material, were inferred to be the primary causes of major landslides, triggered during 5 days of excessively heavy rainfall (400% over the normal average). Additionally, massive toe erosion was observed by streams gushing with course clastic sediments and debris. The destructive nature of such multi-hazards was evoked by unscientific modifications of slopes, mismanagement of water drainage, unplanned residential developments, across the channel courses and within active floodplain of rivers, and lack of early warning schemes for landslide.

中文翻译：

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2019 年滑坡的成因：印度喀拉拉邦马拉普拉姆和瓦亚纳德地区的案例研究

2019 年 8 月 4 日至 2019 年 8 月 8 日，在印度喀拉拉邦马拉普拉姆地区的卡瓦拉帕拉和普图马拉的北坡，史无前例的持续强季风降雨引发了几次山体滑坡和洪水。分析了子流域宽流域内的地质和地貌场设置，初步评估了滑坡的成因。除了在高滑坡易发地区建立适应性强的社区恢复力模型外，本文还提供了对滑坡成因的见解，以及对适当的土地利用规划和部署实时洪水和滑坡监测系统的建议。结构扰动的弱化基岩和一般无能的残余蚀变产物，由于粗心大意的人为干预而加剧，在下伏地球物质过饱和的情况下，内聚强度的降低被推断为主要山体滑坡的主要原因，在 5 天的超强降雨（比正常平均值高 400%）期间引发。此外，通过涌出碎屑沉积物和碎屑的溪流观察到大规模的脚趾侵蚀。这种多重灾害的破坏性是由不科学的斜坡改造、排水管理不善、计划外的住宅开发、跨河道和活跃的河流洪泛区以及缺乏滑坡预警计划引起的。在 5 天的超强降雨期间触发（比正常平均值高 400%）。此外，通过涌出碎屑沉积物和碎屑的溪流观察到大规模的脚趾侵蚀。这种多重灾害的破坏性是由不科学的斜坡改造、排水管理不善、计划外的住宅开发、跨河道和活跃的河流洪泛区以及缺乏滑坡预警计划引起的。在 5 天的超强降雨期间触发（比正常平均值高 400%）。此外，通过涌出碎屑沉积物和碎屑的溪流观察到大规模的脚趾侵蚀。这种多重灾害的破坏性是由不科学的斜坡改造、排水管理不善、计划外的住宅开发、跨河道和活跃的河流洪泛区以及缺乏滑坡预警计划引起的。