Imaging Deeper Geology in the Langkasuka Basin by using Full Tensor Gradiometry (FTG) Gravity

The Langkasuka Basin is the frontier of oil & gas exploration in Malaysia. It is located at the north of the Malacca Strait, offshore of West Peninsular Malaysia. PETRONAS has recently initiated a multi-client 2D seismic survey to explore and identify the hydrocarbon potential in the open blocks of PM320 and PM321 of this basin. For the past five decades, few hundred kilometres of 2D seismic lines were acquired but failed to image the deeper pre-Tertiary formation due to poor quality data. PETRONAS also had conducted Full Tensor Gradiometry (FTG) survey in 2018 that covered the entire open blocks of PM320 and PM321. This paper describes the use of FTG Tzz and Tz gravity data to visualize deeper pre-Tertiary formations in the Langkasuka Basin by using Cauchy downward continuation solution. Thicker sediments beyond the pre-Tertiary basement were visualized from the Tz Cauchy solution which suggesting possible Mesozoic-Palaeozoic sediments before reaching the basement. Utilizing Cauchy downward continuation applied to FTG gravity data can serve as a valuable adjunct to seismic interpretation efforts, particularly in delineating subsurface structures beneath the pre-Tertiary basement. This approach holds promise for targeting Mesozoic-Palaeozoic geological formations, potentially extending exploration horizons beyond Tertiary formations.