<![CDATA[This study investigates tectonic control on karstification within Eocene Faumai Formation in Bird’s Head region, West Papua, Indonesia. An integrated workflow was applied using surface outcrop observations, drilling indicators (including total mud losses, weight on bit, standpipe pressure, and equivalent circulating density), drilling events, and 3D seismic data from Tangguh area. The aim was to identify the distribution of karstified intervals, evaluate role of structural deformation, and reconstruct tectono-stratigraphic evolution associated with karst development.Faumai Formation is subdivided into four sequences, with karst development most pronounced in Faumai-2 interval. Evidence of karstification includes cave occurrences in outcrops, significant drilling mud losses, and low-impedance or trough reflectivity to chaotic seismic anomalies interpreted as subsurface cavities and collapse-related features concentrated along fault-controlled zones.The results indicate that oblique convergence among Australian, Caroline, and Pacific plates drove Late Oligocene uplift, exposing carbonate units to subaerial conditions and enabling meteoric dissolution along structural highs, fractures, and fault networks. Grain-supported dolomitic textures in the Faumai-2 interval suggest more favorable rock properties for karst development than in other sequences. Younger tectonic reactivation during Pleistocene subsequently produced collapse features recognized in both seismic and outcrop data, indicating that karstification in Faumai Formation is a multi-phase process controlled by both tectonics and carbonate facies architecture.]]>
