Gravity And Magnetic Data Reduction Software (Gramag2dcon) For Sites Characterization

Perisian kaedah medan keupayaan masa kini lebih menumpukan kepada pentafsiran dan analisis data yang menyebabkan kurangnya perisian kaedah medan keupayaan untuk pemprosesan data. Ini telah menyebabkan pemprosesan data untuk kaedah graviti dan magnetik menjadi satu tugas yang renyah kerana perlu memilih samada untuk memproses data secara manual atau menggunakan perisian yang rumit yang memberi tumpuan lebih kepada pemodelan data dan penapisan data. Dengan membangunkan perisian baharu yang dinamakan GraMag2DCon di mana kombinasi pemprosesan data kedua-dua graviti dan magnetik dimasukkan, pemprosesan data untuk kaedah medan keupayaan akan menjadi lebih mudah. Perisian GraMag2DCon merangkumi pengimportan dan pengeksportan data, dan juga mampu mengubah sebarang data semasa pemprosesan data. Perisian ini juga mampu untuk memberi isyarat kepada pengguna sekiranya berlaku kesilapan atau kesalahan semasa pemprosesan data yang boleh menjimatkan banyak masa. Present potential field methods software are focuses more on data interpretation and analysis which resulted in the lack of data processing software for potential field methods. This caused processing gravity and magnetic methods become a tedious task as one will opted either to manually process the data or used the complicated software which focuses more on data modeling and filtering. By developing new software named GraMag2DCon which include the combination of both gravity and magnetic data processing, data processing for potential field methods will be much easier. GraMag2DCon software includes importing and exporting the data, as well as able to edit any data during data processing. This software also able to alert the user if any error or mistakes occur during data processing which can save a lot of time

Ce anomaly in I‒type granitic soil from Kuantan, Peninsular Malaysia: retention of zircon in the weathering product

This paper describes the Ce anomaly observed in granitic soil from the humid, tropical area of Kuantan, Pahang, Peninsular Malaysia. Three granite rock soil profiles from Kuantan, were sampled and all samples were analysed for rare earth elements. All the profiles of the granitic soil samples show prominent positive Ce anomalies, with the Ce/Ce* ratio values (Ce/Ce*= CeN/√LaN.PrN) ranging from 1.2 to 125. l. Ce4+ is compatible in zircon because it has also the same charge and a similar ionic radius as to Zr4+ (Ce4+ = 0.97 Å; Zr4+ = 0.84 Å). The retention of zircon in the weathering product of the granitic rocks will increase the Ce content in the soil. Thus it is likely that the positive Ce anomaly in the REE profile of the Kuantan Granites may also have resulted from retention of zircon in the weathering product

Implementing Digital Edge Enhancers on Improved High-Resolution Aeromagnetic Signals for Structural-Depth Analysis around the Middle Benue Trough, Nigeria

Digital edge detector operations using magnetic derivatives in conjunction with spectra depth analysis were performed on high-resolution aeromagnetic signals to enhance the delineation and interpretation of depth, structural, and intrasedimentary features within the Middle Benue Trough (MBT) of North Central Nigeria, which could serve as a guide for mineral exploration. The derivatives revealed high-amplitude and short-wavelength anomalies over areas underlain by crystalline basement complexes, major volcanic zones, and aggregates of intrasedimentary volcanic and plutonic rocks. Geologic lineaments trending predominantly NE–SW and NW–SE, as well as minor trends of E–W and N–S, suggest that the area has undergone differential stress regimes across geologic time. The spectral depth analysis indicates a two-source depth model. The deep depth ranges from 1.9 to 6.1 km with an average of 3.9 km, whereas the shallow depth ranges between 0.3 and 1.9 km with an average of 0.8 km and is found to emanate from magnetic signals of post-Cretaceous near-surface igneous intrusions as well as other magnetized bodies embedded within the sediments. The spatial distribution of various hydrothermal minerals such as lead–zinc–barite deposits, as well as salt mineralization, is associated with the widespread Tertiary–recent magmatism and governed by pre-existing tectonic structures in the region

Empirical Correlation Between Electrical Resistivity and Engineering Properties of Soils

Soil's electrical properties are the parameters of natural and artificially created electrical fields in soil and are influenced by distribution of mobile electrical charges, mostly inorganic ions. We aim to determine practically-applicable relations with which to determine soil moisture content and void ratio based on electrical resistivity measurements taken from two different sites in Penang Island. In this study, analysis was conducted to determine the relationship between soil electrical resistivity, moisture content, and void ratio. Moreover, an initial analysis was conducted to determine the variation between the coefficient of gradation with moisture content and void ratio for all data. The developed empirical correlation found in this study can be used as an initial guideline for the further study of tropical soil

Implementing Digital Edge Enhancers on Improved High-Resolution Aeromagnetic Signals for Structural-Depth Analysis around the Middle Benue Trough, Nigeria

Digital edge detector operations using magnetic derivatives in conjunction with spectra depth analysis were performed on high-resolution aeromagnetic signals to enhance the delineation and interpretation of depth, structural, and intrasedimentary features within the Middle Benue Trough (MBT) of North Central Nigeria, which could serve as a guide for mineral exploration. The derivatives revealed high-amplitude and short-wavelength anomalies over areas underlain by crystalline basement complexes, major volcanic zones, and aggregates of intrasedimentary volcanic and plutonic rocks. Geologic lineaments trending predominantly NE–SW and NW–SE, as well as minor trends of E–W and N–S, suggest that the area has undergone differential stress regimes across geologic time. The spectral depth analysis indicates a two-source depth model. The deep depth ranges from 1.9 to 6.1 km with an average of 3.9 km, whereas the shallow depth ranges between 0.3 and 1.9 km with an average of 0.8 km and is found to emanate from magnetic signals of post-Cretaceous near-surface igneous intrusions as well as other magnetized bodies embedded within the sediments. The spatial distribution of various hydrothermal minerals such as lead–zinc–barite deposits, as well as salt mineralization, is associated with the widespread Tertiary–recent magmatism and governed by pre-existing tectonic structures in the region

Slope monitoring: an application of time-lapse electrical resistivity imaging method in Bukit Antarabangsa, Kuala Lumpur

Slope monitoring study using 2-D electrical resistivity imaging method was conducted on a slope where a massive landslide occurred in December 2008 in Bukit Antarabangsa, Kuala Lumpur, Malaysia. The main objective of the study is to determine the subsurface resistivity distribution of the study area and to map the risk/potential zone of landslide in the future. To detect the changes in the subsurface resistivity distribution due to variation in water saturation in the subsurface, time-lapse electrical resistivity imaging method was applied in this study. Repeated measurements of electrical resistivity over chosen lines at different times were done to monitor the changes in the subsurface resistivity distribution. The results obtained from the time-lapse electrical resistivity shows that there are significant changes in the subsurface resistivity distribution during different periods. Locations of possible slope failure are identified along the slope and are divided into Zone 1 and Zone 2. Weak zones are characterized by the large proportion of high water saturation zones and low resistivity values which are highly affected by the supply of water into the subsurface as well as the properties of the subsurface materials. These particular regions are more susceptible towards slope failure as high water content will ease the movement of soil in the subsurface. Thus, proper mitigation must be done at the problematic zones to prevent the occurrence of slope failure in the future

Analyses of magnetic and gravity data in search for meteorite impact crater at Bukit Bunuh, Lenggong, Perak, Malaysia

Analyses and interpretation of magnetic and gravity fields data acquired at Bukit Bunuh, Lenggong, Perak, Malaysia have been carried out in this study. The objective is to identify the meteorite impact crater and possible rebound locations. This study was instigated by an archaeological investigation carried out by the Centre for Global Archaeological Research, Universiti Sains Malaysia. The investigation suggested evidences of shock metamorphisms (suevite breccia) and crater morphology at Bukit Bunuh in Lenggong area of northern Perak, Malaysia. To justify the occurrence of the impact crater, ground magnetic and gravity surveys were conducted first as regional study in the entire area, followed by detailed study at the suspected crater region. Data from both surveys were compiled and corrected. The residual magnetic data ranged between -272 nT and +134.2 nT, whereas the Bouguer gravity data were between -25 mGal and 120 mGal. Both the magnetic and gravity data were gridded and plotted for qualitative interpretation. It was found that low magnetic and gravity region, believed to be an impact crater which is now filled with sediments and surrounded by a highly magnetised shallow bedrock, exists at the mid-part of the study area. Other high magnetic and gravity key features located within the central regions are interpreted as rebounds. In conclusion, the impact structure was successfully modelled as a complex impact crater