Massive landslides can generate significant tsunamis and endanger coastal communities, as shown by recent catastrophic events such the 2018 Palu Tsunami Sunda Strait (e.g., Heidarzadeh et al. 2018; Takabatake 2019). While a number of experimental studies have been conducted to investigate landslide generated tsunamis, most were performed using two dimensional (2D) wave flumes Fritz 2004; 2020)....