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Wiriagar Deep field is the second biggest gas field in Greater Tangguh area, Papua Barat, Eastern Indonesia. The field is situated in a NW-SE direction covering both onshore and offshore areas. The first gas discovery was in 1994 with the Wiriagar Deep-1 well, which found pay in shallow marine Jurassic and deep-water stacked Paleocene reservoir intervals.
The Paleocene deep-water stacking reservoirs are subdivided into five zones with multi-TCF Gas Initial in Place for all zones. The Paleocene lobes sandstone interval, identified as Zone 1, is the one of the reservoir potentials with widespread laterally distributed across Wiriagar Deep field area.

Based on core and log description from ten wells, Zone 1 is sub-divided into two lobe complexes. Each lobe complex is estimated to be c.30 km long, c.15 km wide, and have an average gross thickness of c.30 m. Within each lobe complex, three lobe element sets, bounded by hemipelagic claystones, are recognised.

Gas flow rates of up to 1.7 MMscfd are recorded from Zone 1. The key development risk for this zone is quality and deliverability of this low permeability, tight formation, leading to challenging economics. The tight formation is mainly affected by higher lithic content, calcite cementation and compaction. Permeability from DST ranges from 0.2 to 0.8 mD with potential higher permeability from core data (RCA) which averaging 2 mD. This tight reservoir likely requires hydraulic fracture to flow gas at economic rates.