Characterization of Landslide geometry using Seismic Refraction Tomography in the GayoLues, Indonesia

Abstract

Landslides are the most common geological phenomenon in Indonesia.The event is damage to public infrastructure, and fatalities was a big impact. Therefore, mapping the geometry of landslides is a part of the mitigation effort possible by geophysical methods. In this research, we applied seismic refraction tomography (SRT) to study the geometry of the sliding zone from the landslide event.TheNational Disaster Management Authority reported that the area was frequently occurring landslide disaster, i.e. 2018, 2019 and 2020 which caused the public infrastructure and obstructed the road access from the central to the west of Aceh. The SRT was measured in two profileslong the road.Data measurements were conducted on the side of the Babahrot - GayoLues road section that had experienced landslides.Measurements were made using the Seismograph PASI 16S24-P and 24 geophones to obtain a 92-meterlong profile with 2 meter spacing between the geophones. P-wave velocity data modeling is done using ZondST2D software.The results of modeling profiles 1 and 2 describe three different subsurface layers.The SRT profile 1 model consists of slate (0.2 - 0.7 km/s), clay (0.8 - 1.3 km/s), and sandy clay (1.4 - 1.9 km/s).While, the model of profile 2 consists of slate (0.5 - 1.0 km/s), clay (1.1 - 1.6 km/ s), and sandy clay (1.7 - 2.5 km/s).The contrasting wave velocity model shows that the SRT method can be used in landslide studies as a reference in determining the mechanism of the landslide system.

Integrated Geophysical Analysis for Landslide Risk Mitigation: A Case Study on the Weak Zone Area of Jantho-Lamno Route, Aceh, Indonesia

“…In the seismic refraction data processing using ZONDST2D [6], the initial step involves acquiring raw data through a survey along the Jantho-Lamno Road, recording travel times of refracted seismic waves. Subsequently, the data undergoes preprocessing to eliminate noise and enhance quality before being imported into ZONDST2D.…”

“…Our original achievement lies in the precise differentiation of rock layers and the identification of both weakened upper layers and potential slip planes in deeper formations. By correlating seismic [6,7,8] and resistivity data [9,10,11], the study predicts landslide-prone zones and contributes to a deeper understanding of geological features that contribute to slope failures [12]. This integrated approach not only surpasses the limitations of singular geophysical techniques but also offers a more effective means of formulating targeted protective measures to enhance the resilience of critical transportation routes.…”

Shallow Seismic Refraction Tomography Images from the Pieniny Klippen Belt (Southern Poland)

“…Seismic refraction tomography performs well in many situations where traditional seismic refraction methods fail, such as in the presence of velocity structures with both lateral and vertical velocity gradients [29,30]. SRT is commonly applied for, e.g., bedrock mapping [31][32][33], groundwater level determination [34,35], the characterization of landslide geometry [36,37], the assessment of rippability [38,39] and seepage detection [40].…”

A combination of seismic refraction and ambient noise methods to detect landslide-prone materials

“…These methods offer broader spatial coverage than geotechnical investigations to quantify the variability and physical state of the hydrogeological parameters associated with the sliding surface (Uhlemann et al, 2016). Traditional seismic methods for subsurface characterization include seismic refraction and spectral analysis of surface waves (whether from an active or passive source) to obtain, more accurately, the bedrock irregularity (Harba et al, 2019;Uhlemann et al, 2016;Zainal et al, 2021). However, to cover large areas or acquire data in topographically complicated terrain, the results could be only a sample of the magnitude of the problem in the case of landslides.…”