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Geophysical approaches are used for site characterization to determine the dynamic behaviour of soil. Structures built on a site without sufficient assessment are prone to collapse or failure. Thus, before beginning any building activity, it is critical to assess the soil dynamic qualities. This is significant because buildings are constructed on top of the ground surface, supported by the underlying soil and rock. This work aimed to determine a competent layer for building foundations. This study was conducted to evaluate the dynamic soil behaviour of Paya Terubong on Penang Island. Resistivity, Young's modulus, shear modulus, Poisson's ratio, bulk modulus, bulk density, rippability, and material bearing capacity are among the parameters utilised for the characterization. This will be obtained from the electrical resistivity, seismic refraction, and MASW methods. Three layers were detected by these methods. Results from the study indicate that the area is mostly composed of highly dense silty sand and granitic bedrock, which makes it competent for foundation construction since higher compaction raises the ultimate and allowable bearing capacities of the third layer to very high levels. In addition, soil and rock layers identified using geophysical methods match well with the borehole data showing that material stiffness increases with depth. Rippable layers extend from the ground surface to a depth of 3 meters. The calculated values gotten from the soil dynamic properties and material bearing capacity show that the second and third layers have good geotechnical qualities. The ultimate bearing capacities calculated for the first layer range from 453 to 731 kPa, while the second layer capacities range from 1041 to 1691 kPa, and capacities for the third layer range from 2013 to 3650 kPa. For setting up structures, the second layer can support building foundations at a depth of 4 meters from the existing ground level. This approach is cost-effective, saves time, and is non-destructive for site characterization.

Both natural and anthropogenic coastal landforms characterize Penang Island. As years have passed it is a challenge to differentiate the genuineness of landmasses created by natural geological formations or by coastal reclamation projects. An account is given of the environmental impact of solid wastes used for reclaiming land in coastal areas of Penang and of the impact of a major sewage outfall in the western channel. Leaching of heavy metals was shown to be one of the main sources of contamination from solid wastes. This paper presents eight lines of ground penetrating radar (GPR) surveys and sediment analysis to identify the anthropogenic interventions that shaped the urban landscape of Penang Island by excavations, filling, and embankment construction along the coastline and differentiate it from the natural one. The surveys were implemented in two locations, the Batu Ferringhi area, representing the natural coastline, and Persiaran Bayan Indah (the Queensbay Mall area), representing the anthropogenic coastal landform. The apparent depth of penetration that was achieved using a 250-MHz antenna is limited (less than 5 m). The results show between natural and anthropogenic sediment recorded different radar facies. In complement mode, mean grain size distribution, sorting, skewness, and kurtosis graphics of sediment samples from both sites correspond with the GPR data. This technique can likely be applied to the developing coast, where natural and anthropogenic coastal landform data is incomplete, considering future coastline development.

The large or small scale of a landslide is a natural, widespread process, resulting from the downward and outward movement of slope-forming materials, such as sculpting the landscape. Characterized landslide material and properties&rsquo, inhomogeneities conditions become a challenge as the process required the availability of a wide range of data, observations, and measurements with an evaluation of geological and hydrological conditions. Detailed investigations represent an essential component of the landslide risk mitigation process, relying on subsurface investigations, discrete subsurface sampling, and laboratory tests. To extend this approach, seismic refraction and two-dimensional (2-D) resistivity were utilized to study the landslides activities in Ulu Yam. The cross-plot analysis was introduced to integrate the geophysical results based on the criteria of the model. Velocity distributions from seismic refraction revealed the stiffness of the soil, where weak zones identified with values of Vp &le, 1200 m/s, defined as threshold frequency for failure to occur. The 2-D resistivity shows that the weak zones were identified with resistivity values of &lt, 1200 Ωm. The 2-D cross-plot model gives a comprehensive interpretation where a low velocity and resistivity value represents the failure plane of materials to failure. The volume of mass sliding was calculated based on retrieved information from the model.

Mudrock is a type of sedimentary rock whose original constituents are clays and muds. Mudrocks are fine grained siliciclastic which include mudstone and claystone depending on the grain size. The colour of mudstone is a function of its minerology content and geochemistry processes. One common sedimentary structure of mudrocks is lamination due to variations in grain size and composition changes. The importance of mudrocks is as a mixture for cement and to produce brick used for building structure. This research emphasizes on the resistivity value of mudrocks; claystone and mudstone which exist in northwestern of Peninsula Malaysia. Mudstone of Kubang Pasu Formation, red mudstone and grey mudstone of Chepor Member and claystone of Semanggol Formation were chose as the study area as each of the mudrock was formed in a different environmental condition. Electrical resistivity survey was conducted on top of the outcrops using Wenner – Schlumberger array with 1.5 m and 1 m electrode spacing with respect to localities. The data was processed using Res2Dinv software to get the inversion model resistivity and the results were imported to Surfer10 software for labelling purposes. The mudstone resistivity value of Kubang Pasu Formation formed by depositional of calm water gives resistivity value from 20 – 120 Ωm. The red mudstone of Chepor Member formed at high oxidation environment gives resistivity value of 15 – 100 Ωm contrast to grey mudstone which formed under low oxidizing condition gives 120 – 500 Ωm resistivity value. The claystone of Semanggol Formation formed from shallow depositional environment gives resistivity value from 400 – 1000 Ωm. As a conclusion, electrical resistivity survey was successfully applied in differentiating the type of mudrocks. Also, mudrocks formed from different depositional environment gives different values of resistivity.

Rock is a naturally occurring substance. The study of rock properties and its mineral composition have many useful information and benefits, such as for building construction and aggregates. Understanding of how rock material was formed will reveal how it can be used in a building, its limitations and how it will weathered over time. The research objectives are to categorize the rock properties based from the methods of geophysics, geotechnical and petrography analysis, and to identify the possibility of the material used for construction purpose. The location of the study is at Bukit Chondong, Beseri, Perlis, Malaysia. The study was conducted using 2-D resistivity method, geotechnical test and thin section analysis. For 2-D resistivity method, the length of a single survey line is 40 m with minimum of 1 m electrode spacing and the array used was Pole-dipole. For geotechnical test, there are two test conducted on the core samples of mudstone and sandstone, which are permeability test and porosity test. Fi...

This study on the sedimentological and reservoir petrophysical properties (porosity, permeability, density, sonic velocity) of sandstones were conducted on the sedimentary rocks belonging to the Miri Formation (Middle Miocene) from Miri and Nyalau Formation (Middle Miocene) from Bintulu in Sarawak. The objectives are i) to investigate and determine the facies characteristics and reservoir properties of the different types of sandstones, and ii) to establish the relationships between the facies characteristics and petrophysical properties. Two lithofacies have been sampled from the outcrops of Nyalau Formation and four lithofacies from the outcrops of Miri Formation based on lithology, sedimentary structures, fossil traces and bed geometry. These are grouped into four major lithofacies: (i) hummocky cross-stratified sandstones (HCS); (ii) trough cross-bedding sandstones (TCB); (iii) bioturbated sandstones; and (iv) swaley cross-stratified sandstones (SCS). Hummocky and swaley cross-stratified sandstones, trough cross-bedded sandstones and some bioturbated sandstones of Miri formation recorded the highest poro-perm values, with relatively lower density values (as compared Bintulu samples). The TCB sandstones are well sorted sandstones, with minimal mud content. This has contributed to the high poro-perm values. The bioturbated swaley cross-stratified sandstone (MF4) shows high permeabilities in some samples and low permeabilities in others. This reflects the heterogeneity in facies characteristics and poro-perm distribution of bioturbated samples. Bioturbated HCS, the HCS and TCB sandstones of Bintulu show moderate poro-perm values. The Nyalau Formation rocks are older, and thus are expected to have undergone greater compaction than the younger Miri Formation. This is also reflected in the higher density values recorded for all the Bintulu samples. INtrodu Ct Io N In general, facies characteristics determine the overall reservoir properties of sandstones, while diagenetic changes impose a secondary control on their poro-perm characteristics. The purpose of studying the reservoir sedimentological characteristics and petrophysical properties of Tertiary sandstones from Sarawak is to investigate and determine the facies characteristics, and reservoir properties of the different types of sandstones, and to establish the relationships between the facies characteristics and petrophysical properties. This study on the sedimentological and reservoir petrophysical properties (porosity, permeability, density, sonic velocity) of sandstones were conducted on the sedimentary rocks belonging to the Miri Formation (Middle Miocene) from Miri and Nyalau Formation (Middle Miocene) from Bintulu in Sarawak.

Outcrop studies are a fascinating part of geology as it evidently shows the aftermath of how the earth forming processes billion years ago. Outcrops do not cover majority of the Earth's land surface as it is covered by soils or vegetation thus cannot be seen clearly. In Kedah, Malaysia, there are many outcrops exposed in the state. The aim of this research studies was to correlate the parameters of geophysical survey with the properties of the Permian facies of Semanggol Formation in Kedah. The Permian facies consists of bedded chert and claystone. Two geophysical technique, electrical resistivity tomography (ERT) and seismic refraction tomography (SRT) were applied at the same line on top of the outcrop at Bukit Kukus beside Kulim – Baling (Kedah) road. The arrays used for ERT are Pole–dipole and Wenner–Schlumberger. The spacing between electrodes for ERT is 1.5 m while the geophone spacing for SRT is 2 m. Both ERT and SRT line is 60 m and 46 m respectively. Based on the results of both geophysical techniques, relating the porosity and permeability (poroperm) with geophysical parameters, it can be concluded that the bedded chert of low poroperm having seismic velocity and resistivity values at range of 1500 m/s – 2500 m/s and 1400 Ωm – 45000 Ωm. Whereas for claystone, it is very soft and laminated, concluding having high poroperm with seismic velocity between 600 m/s – 1200 m/s and resistivity values between 400 Ωm – 1000 Ωm.

Sandstones are very important as reservoirs for oil and gas; more than 50% of the world’s petroleum reserve is estimated to occur in sandstones. Depositional environments, and thus facies characteristics, determine the overall reservoir properties of sandstones. The purpose of studying the reservoir sedimentological characteristics and petrophysical properties of Tertiary reservoir quality sandstones from Sabah and Sarawak is to investigate and determine the relationships between sedimentological and facies characteristics, and reservoir properties of the different types of sandstones.