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Satellite gravity data can be used in this study to characterise hitherto unexplored regions and enhance scientific understanding of the studied area. However, the geological ambiguity of the study area makes it challenging to figure out the geological interpretation within and around the area. Therefore, this work focused on the Garyan area in the northwest part of Libya for the purpose of identifying geological structures. The Garyan region is a part of Jabal Nafusah (central Jabal) due to its geographic location and the character of the escarpment. The gravity data was analysed, designed, and developed into a geophysical model using the Oasis Montaj programme. Several analytic techniques are applied to gravity datasets for subsurface structure investigation, including (TDR) tilt derivative, (THG) total horizontal gradient, (PS) Power spectrum technique, (AS) Analytical signal, and (ED) Euler deconvolution. The results identified the presence of faults trending in different orientations (N-S, NW-SE, E-W, NNW-SSE, NE-SW), with source depths ranging between 300 and 2300 m, which indicates a complex tectonic history in the area. Clearly, this work will reduce the ambiguity of geological interpretations and provide better information on the dominant trends for future exploration activities in the study region. It also detects the contacts of density variation and estimates the depth of the gravity sources from satellite-EIGEN-6C4 gravity data. [ABSTRACT FROM AUTHOR]

The Tarhona region, which is situated within the northwestern part of Libya, is a part of Jabal Nafusah (eastern Jabal) due to its geographic location and the character of the escarpment. It is restricted to the east by longitudes 13.00° to 14.00° east and to the north by latitudes 31.45° to 32.25° north. The analysis and interpretation of magnetic data can depict previously unknown regions and improve scientific knowledge of the study area. However, the geological ambiguity of the study area makes it challenging to figure out the geological interpretation within and around the area. Therefore, this study aims to delineate structural elements and depths of sources using an aeromagnetic dataset in the Tarhona region in northwest Libya. Magnetic dataset is reduced to the pole (RTP) within Oasis Montaj. Different filters were utilised to magnetic data, including Total horizontal gradient (THG), CET grid analysis, Power spectrum analysis (PS), Analytic signal (AS), 3D Euler deconvolution (ED), and Tilt derivative (TDR). The result shows various fault tendencies in the N-S, NNW-SSE, and NW-SE directions. The depth of faults was determined from 2000 to above 8000 m after applying 3D Euler deconvolution with the TDR derivative. In addition, a rose diagram was prepared for delineating the trend of the faults using edge detection techniques (THG, CET grid analysis, AS, Euler deconvolution, and TDR). The delineation of subsurface structures in the region is helpful for further hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

Ground deformations (e.g., landslide and subsidence) have substantially risen recently around Penang Island, Malaysia. The development of hillslopes for rapid urbanisation and heavy rainfall has detrimental impacts on Penang Island soil layers. Modelling, simulation, and the development of susceptibility maps were past methods used to predict potential ground deformations of Penang Island. There is no published work on the Interferometry Synthetic Aperture Radar (InSAR) technique, where ground deformation of the region has been holistically studied. This work integrates the Persistent Scatterer InSAR (PS-InSAR) technique with Ground Penetrating Radar (GPR) to monitor the deformation on the island and identify possible subsurface causes for the disturbance. Twenty-four descending Sentinel-1A datasets acquired between 14th July 2017 and 13th October 2018 were processed to monitor and map ground deformation areas with a focus on three selected regions- Batu Feringghi (BF), Paya Terubong (PT), and Tanjung Bungah (TB), where multiple landslides occurred between 2017 and 2018. InSAR results were later analysed using the Statistical Package for the Social Sciences (SPSS) tool and validated by the available Global Positioning System (GPS) analysis. InSAR analyses reveal the mean deformation values of -3.13 mm/yr, -2.76 mm/yr and -4.77 mm/yr for the BF, PT, and TB areas. GPR surveys were conducted with a 300/800 MHz dual-frequency antenna at the three selected study areas. Anomalies (wall cracks, road fissures, cavities, drains, and pipes) detected using GPR profiles correlated well with the permanent scatterer points calculated using the InSAR technique. [ABSTRACT FROM AUTHOR]

Slope failure is Penang Island's most critical geohazards that inflict significant economic damage each year. Penang landslide is considered one of the most disastrous landslide regions in Malaysia. The threat to lives and property had been associated with the slope instability issues for decades and continuous rain that usually lasts for hours/days. Earlier research employed simulation and modeling to address this hazard, but InSAR technique has not been fully utilized to quantify Penang Island's movements. It now requires proper monitoring using satellite techniques. Sentinel-1A S-1A images acquired enables Synthetic Aperture Radar (SAR) processing technique looks very promising. The data were processed using a versatile and powerful tool called SARPROZ software. The Permanent Scatterer Interferometric SAR (PS-InSAR) technique was applied to monitor ground deformation in Penang Island, Malaysia, as various deformations have been reported for years. The results of S-1A data show slow ground deformation values ranging between −9.19 mm/yr and - 10.00 mm/yr for subsidence pattern and from 5.00 mm/yr to 4.66 mm/yr for uplift behavior. The results with S-1A data confirmed a trend of deformations around the regions. This reflects the improvement of the S-1A datasets for the PS-InSAR analysis in the region. InSAR result was validated using available GPS analysis. The results were also related to some works on physical parameters such as rainfall, slope, geology, and soil properties of the region for comparison. However, the detailed spatial pattern of surface displacement in the middle of the island is not clear as persistent scatterer has a limitation in the vegetated and rural areas. [ABSTRACT FROM AUTHOR]