Survey of Warnimont Bluff, Wisconsin, February 2020

High lake levels are reducing beach area along the Lake Michigan coastline and allowing wave action to erode the bases of coastal bluffs at the highest rate of the past 30 years. Sediment budget calculations have shown that bluff erosion is the dominant source of sand and gravel-sized particles that are mobilized into beaches and the nearshore system. Researchers have found that the leading cause of bluff erosion is shallow to intermediate depth translational landslides. Therefore, estimating lake sediment budgets depends on an understanding of the mechanisms that lead to landslide failure. This study will provide a comprehensive analysis of bluff stability for bluffs affected by landslide failure coupled with an analysis of bluff composition to determine the composition of sediment contributions of coastal bluffs to the southeast Lake Michigan sediment budget.

高水位湖面正在减少密歇根湖海岸线上的海滩面积，并允许波浪作用以过去30年中最高速度侵蚀海岸悬崖的底部。沉积物预算计算表明，悬崖侵蚀是海滩和近岸系统中被激活的沙砾大小颗粒的主要来源。研究人员发现，悬崖侵蚀的主要原因是浅至中等深度的横向滑坡。因此，估计湖泊沉积物预算取决于对导致滑坡失败的机制的理解。本研究将对受滑坡失败影响的悬崖稳定性进行综合分析，并结合对悬崖组成的分析，以确定海岸悬崖对东南密歇根湖沉积物预算中沉积物贡献的组成。