LECTURE 24

LECTURE 24

1. COOPER-EROMANGA BASINS CASE STUDY

   • vertically stacked basin in central Aus
     • all vertically stacked basins have same geographic location, but different age&distribution - different name
   • Ref Sping carried out the first exploration
   • Santos, Beach & Stuart currently produce in the basins
   • Cooper-Eromanga basins
     • Cooper is Permian age (oldest)200/230-300Ma
     • Eromanga basin is Triassic to Early Cretaceous age (youngest) <200/230Ma
     • two basin are separated by an unconformity (Triassic-Jurassic)
   • First discovery at Gidgealpa field in 1963 (structural high in Cooper basin)
     • Gidgealpa-1 well
       • Gidgealpa-2 well
         • drill-on structure - first gas discovery from Toolachee Formation
         • Subsequent wells made gas discovery from Toolahee, Patchawarra, Tirrawarra Formation
           • Oil is not discovered until 1984 from Eromanga rocks
       • drilled off-structure - resulted in Permian gas shows
   • Later discover at Permian Zero Edge
     • Reservoir in Eromanga rock
       • Sourced from Cooper rocks
   • 1 well can drill through many basin