Karstification in carbonate platforms of the Miocene age in Central Luconia province, offshore Sarawak, Malaysia, has been discussed since the onset of exploration and initial discoveries in the region, with over 200 mapped platforms to date. An extensive drilling program over the last decade confirmed the existence of karst during the drilling process where issues such as total loss circulation and bit drops were common. Karst in Central Luconia has been proposed by several authors; however, detailed quantitative description of the observed features have not yet been conducted. This study involves systematic mapping of loss circulation depths, chalkified/rubble/vuggy zones described from cores, and vugs of >2 mm in size and moldic porosity observed on thin sections of the Jintan platform. These data supplement the interpretation of karst from multiple 3D seismic attributes. Seismic interpretation of the Jintan and M1 platforms revealed an extensive dendritic pattern which is on average 70–100 m deep and 3–5 km long, and circular geobodies of 1 km in width that exist on the upper part of the platform. Spectral decomposition, also known as time-frequency analysis, was used to enhance the interpretation of karst features on seismics within a specific wavelength. In this study, a comparison of three spectral decomposition methods applied on the 3D seismic cube of the Jintan and M1 platforms was undertaken to determine the method which allowed for better delineation of the karst features. The results show that the short-time Fourier transform (STFT) method using frequencies of 46, 54, and 60 Hz delineated most of the karst features compared to the continuous wavelet transform (CWT) Morlet and CWT Ricker wavelet methods. This paper aims to discuss the dimensions, evolution and geometry of the karst features quantitatively on three selected karst horizons named “K1”, “K2”, “K3”. Interpretation revealed that the dendritic karst features were found to be most prominent on the K2 horizon which lies below a conspicuous change of the external geomorphology of the platform. Backstepping of the platform margin by 12 km is observed in both platforms. Quantitative seismic interpretation shows that the karst observed in M1 platform is approximately 70–100 m deep, and the dendritic features are around 1–2 km in length and approximately 500 m wide; whereas, in the Jintan platform the dendritic features observed are up to 5 km in length with several 1 km wide circular/sinkhole features. More than 20 dendritic features orientated SE and NS were mapped mainly in the transitional area as well as the center of both platforms. The nature of the karst morphology in Central Luconia remains controversial; however, it is proposed to be of mixing zone karst origin.

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<p>Geoscience data usually is complex and comes at different scales. Effective visualization tools are crucial for efficiently examining properties and correlations when working with the datasets and for telling geoscience stories around them. Virtual Reality (VR) leads users to an immersive experience and allows for true spatial awareness and depth perception. We find that VR enhances knowledge transfer and adds a gamification moment.</p><p>In the energy industry and Academia, large amounts of multiscale geo data are compiled but often remain segregated and underutilized. Core data, for example, is sitting in remote core centers and is not readily available to be integrated for improving the quality of 3D geological models and interpretations.</p><p>Likewise, numerous supplemental information and geological images are required to improve the quality of any geoscience simulations. Traditionally, most visualization is tied to display on 2D computer screens. Users (geologists, teachers, and students) rely on advanced real-time visualization and interaction methods customized to geospatial data at different scales. It is the user’s objective to improve their observations and interpretations at different dimensions (2D and 3D).</p><p> In this work, we study the effectiveness and usability of Virtual Reality tools for training and collaborative decision purposes. The multiscale data includes sets of cores, logs, sedimentological descriptions, and seismic. All data is presented in a unique virtual data room and immersive presentation.  The geological model and data of different scales are visualized simultaneously and interpreted jointly.</p><p>Finally, we highlight the advantages of VR for training students in geoscience and geo data-data interpretation.  This is not limited to but especially true for physical data sets (e.g., core) or models from remote locations (e.g., outcrop) that are difficult to visit. Specific VR tools allow students to navigate in an immersive way through virtual geological multiscale datasets. The interactive environment makes the process of learning fun, removes distractions, and immerses the students in the subject matter at hand. Together with dedicated VR storytelling tools and supplemental documentation, this results in a quicker and deeper understanding of complex geological settings.</p>

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