structural malay basin

structural malay basin

1. fold system

   • elongated parallel to the basin axis which is NW-SE
   • 3 main domains:
     • basin hinge fold system
       • bounded by the Hinge Fault zone
       • length of the folds : 30 km- 70 km
       • axis orientations: change from north to south
       • Northern most folds:
         • Pilong-Gajah and Ular-Damar folds
           • axis orientation: north-south axes
           • shape: elleptical
           • located at the North striking faults
       • Southern part:
         • Bintang Lawit fold
           • geometry: rounded dome
           • axis: east-west
       • eastern margin:
         • The Bedong Tujuh fold
           • axis: NW-SE
     • basin ramp fold domain
       • location: four east-west syn rift depression
         • Peta sub-graben, Abu-Bubu sub-basin, Simpur sub-basin and Selanchar sub-basin and one NW-SE syn-rift depression (Bunga Raya sub-basin)
     • basin axis fold domain
       • 2 subdomains
         • Northern: Jerneh-Tangga
           • shape: rhombic
           • Fold axis: east- west
         • Southern: Dulang-Ledang
           • Fold axis: WNW-ESE
           • southern flanks of the folds are steeper and their fold axes are longer

2. fault system

   • 2 domains
     • high density fault domain
       • sites of major fault systems
       • areas with high density of faults
         • western and central region
     • low density fault domain
       • western and eastern fault system seperated by the Central Malay fault system
     • oriented north-south and are arranged alternately east west