Application of remote sensing in the identification of the geological terrain features in Cameron Highlands, Malaysia

The geological terrain mapping conducted by the Department of Mineral and Geosciences, Malaysia (JMG) is time-consuming especially for inaccessible or remote area. In order to improve the current practice, remotely sensed data such as aerial photographs and Landsat imagery were used to identify geological terrain features in Cameron Highlands, Pahang. It was found that features such as hillcrest, sideslope, footslope, straight slope, convex slope and concave slope were easily delineated using aerial photographs draped over a digital elevation model (DEM) compared to using Landsat imagery

ROCK SLOPE STABILITY ASSESSMENT OF LIMESTONE HILLS, SOUTHERN KINTA VALLEY, IPOH, PERAK, MALAYSIA

The uniqueness of the karst topography of Kinta Valley is the result of the spectacular shaped steep-sided limestone towers. The instability of these hillslopes however, may affect the vulnerability of the surrounding area. This paper presents the results of slope stability assessment by using kinematic analysis to investigate the possible failure modes of 7 slopes in Gua Naga Mas (GNM1, GNM2 and GNM3), Gua Kandu (GK1, GK2 and GK3) and Gua Tempurung (GT) located in the southern part of the Kinta Valley, Ipoh, Perak. From the results of the slope stability assessment, it was determined that planar failure and wedge failure were the main failure modes. The GNM1 slope of Gua Naga Mas consist of four wedge failures and a planar failure with dip directions/dip angles of 005⁰/54⁰, 354⁰/59⁰, 124⁰/52⁰, 360⁰/50⁰ and 063⁰/70⁰ respectively. The GNM2 slope consists of a wedge failure with the dip direction/dip angle of 021⁰/64⁰. Two wedge failures and a planar failure were identified on slope GNM3 with the respective dip directions/dip angles of 336⁰/49⁰, 301⁰/68⁰ and 270⁰/71⁰. The GK1 slope for Gua Kandu consists of wedge and planar failures with dip directions/dip angles of 231⁰/49⁰ and 217⁰/49⁰ respectively. The mode of failure at GK2 slope was identified as wedge failure with the dip direction/dip angle of 154⁰/44⁰. No mode of failure was identified on slope of GK3. Slope GT of Gua Tempurung was identified to have two wedge failures with dip directions/dip angles of 011⁰/49⁰ and 321⁰/48⁰ respectively

Rock Slope Stability Assessment of Limestone Hills in Northern Kinta Valley, Ipoh, Perak, Malaysia

The uniqueness of karsttopography in Kinta Valley lies with the spectacular shape of the steep-sided limestone towers. However, theinstability ofthese hillslopes may affect the vulnerability of the surrounding area. Thus, this study was conducted with the objective to investigate the failure modes of 9 slopes in the vicinity ofnorthernKinta Valley, Ipoh, Perak. There were two types of failure modes identified in the study area,which are planar and wedge failures. Planar failures were identified on slope GL3of Gunung Lang and slope GR3of Gunung Rapat with the dip direction and dip angle of 280⁰/79⁰ and 004⁰/ 64⁰ respectively. Two wedge failures were identified on slope QXL1of Qing Xing Ling, Taman Saikat with dip direction and dip angle of 252⁰/82⁰ and 302⁰/74⁰ respectively. A wedge failure was identified on slope GL3 for Gunung Lang, slope GR1, slope GR3 for Gunung Rapat and slope QXL2 for Qing Xing Ling,Taman Saikat. The dip direction and dip angle for the respective wedges failure were 345⁰/65⁰, 036⁰/ 49⁰, 006⁰/ 64⁰ and 025⁰/60⁰. No failure was identified on slope GL1, and slope GL2,forGunung Lang and slope GR2, and slope GR4forGunungRapat

ACTIVE FAULTS IN PENINSULAR MALAYSIA WITH EMPHASIS ON ACTIVE GEOMORPHIC FEATURES OF BUKIT TINGGI REGION

In this paper, we summarize the results of recent geomorphic investigations of active faults in Peninsular Malaysia with emphasize on Bukit Tinggi region using IFSAR and field verification. The evidences for active faulting, and their characteristics are discussed. Several fault segments within the Bukit Tinggi fault zone are deemed active. The Bukit Tingg fault zone is considered to be active and is a potential source of future earthquakes. Outside Bukit Tinggi area, the Benus and Karak faults are also deemed active. These fault zones show the following active neotectonic geomorphic features: 1) displays geomorphic features indicative of recent fault activity; 2) show evidence for displacement in young (Late Quaternary) deposits or surfaces; and/or 3) is associated with a pattern of microearthquakes suggestive of an active faults. They were ancient faults that were reactivated in the Quaternary period and continued into the present. The magnitude of paleoearthquake estimated from the activity and stream offsets suggest a minimum of 6 magnitude on the Richter scale have affected the region due to movements along these faults. Over the past decades, Peninsular Malaysia has experienced mild earthquakes. Virtually all earthquakes recorded in Peninsular Malaysia are under magnitude 5.0. However, the regognition of active faults exhibiting active tectonic landforms suggestes that these faults have produced damaging earthquakes before and have potential to trigger similar tremors in the future

A knowledge-driven GIS modeling technique for groundwater potential mapping at the Upper Langat Basin, Malaysia.

The aim of this paper is to use a knowledge-driven expert-based geographical information system (GIS) model coupling with remote-sensing-derived parameters for groundwater potential mapping in an area of the Upper Langat Basin, Malaysia. In this study, nine groundwater storage controlling parameters that affect groundwater occurrences are derived from remotely sensed imagery, available maps, and associated databases. Those parameters are: lithology, slope, lineament, land use, soil, rainfall, drainage density, elevation, and geomorphology. Then the parameter layers were integrated and modeled using a knowledge-driven GIS of weighted linear combination. The weightage and score for each parameter and their classes are based on the Malaysian groundwater expert opinion survey. The predicted groundwater potential map was classified into four distinct zones based on the classification scheme designed by Department of Minerals and Geoscience Malaysia (JMG). The results showed that about 17% of the study area falls under low-potential zone, with 66% on moderate-potential zone, 15% with high-potential zone, and only 0.45% falls under very-high-potential zone. The results obtained in this study were validated with the groundwater borehole wells data compiled by the JMG and showed 76% of prediction accuracy. In addition statistical analysis indicated that hard rock dominant of the study area is controlled by secondary porosity such as distance from lineament and density of lineament. There are high correlations between area percentage of predicted groundwater potential zones and groundwater well yield. Results obtained from this study can be useful for future planning of groundwater exploration, planning and development by related agencies in Malaysia which provide a rapid method and reduce cost as well as less time consuming. The results may be also transferable to other areas of similar hydrological characteristics