Abstract
Subsurface soil varies from place to place due to the rock type, its mineral constituents, the climate
 of the area, time and other geological activities such as meteorite impact. The process that leads to
 the formation of impact crater can cause great variation in the subsurface soil characteristics, which
 may have an effect on civil engineering structures. Hence, the need to evaluate the subsurface soil
 of the impacted area. In this study, Seismic refraction and borehole data were used to achieve the
 aim. The result revealed that the overburden layer inside the crater is dominated by low-velocity
 values (< 750 m/s) which correspond with low N-values. Moderate seismic velocity values (750 –
 1400 m/s) with moderate to high N-values were predominant for overburden soil within the crater
 rim and outside the crater. Slightly, moderately and highly weathered granite was observed at all
 survey lines with velocity values ranging from 1200 - 3450 m/s. The low N-values with lowvelocity values obtained inside the crater are indications that the subsurface soil inside the impact
 crater area has been deformed and weakened as evident by the presence of brecciation which
 occurred during the impact process.
Highlights
Subsurface soil distribution and occurrence vary from place to place
Based on the borehole data BH1 along SL1, slightly and highly weathered granite was found at depth of 15 m with velocity of 1290 - 2160 m/s; moderately and highly weathered granitic rock was encountered at depth of 12 m with velocity of 1200 - 1540 m/s for BH2 along SL2
The low N-values of inside the crater which corresponds with low seismic velocity (Bery & Rosli, 2012) is an indication that the subsurface soil inside the impact crater area has been deformed due to brecciation during the impact process
Summary
Subsurface soil distribution and occurrence vary from place to place. The variation of the soil depends on the climate of the area, rock type, its mineral constituent, vegetation, topography and time (Daniel, 2004; Roy & Bhalla, 2017). Several studies (Arifin et al, 2010; Azwin et al, 2015; Nawawi et al, 2004; Nur Amalina et al, 2012; Rosli et al, 2012; Rosli et al, 2014) have been conducted at Bukit Bunuh Lenggong Perak, Malaysia with the aim of identifying the impact crater. This paper is aimed at evaluating the subsurface soil within and outside the impact crater area using seismic refraction and SPT N-value. Bukit Bunuh is situated in Lenggong town of Perak, Malaysia It lies between two mountain ranges, Titiwangsa Range and Bintang Hill with rugged topography. Geological map of Lenggong Valley showing the location of Bukit Bunuh was depicted at Figure 1
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
