Evolution of The Salawati Structures, Eastern Indonesia – A Frontal Sorong Fault Deformation



Major Sorong Fault, a WSW-ENE trending left-lateral wrench fault terminates the Salawati Basin to the north and northwest. The fault has strongly controlled the basin’s structures since the mid-Pliocene and responsible for the present structural style of the basin. Four structural grains can be recognized : normal faults, strike-slip faults, fold-reverse fault belts, and diapiric structures. Four structural trends can be recognized : Salawati, Klasofo, Walio, and Cenderawasih trends. Based on left-lateral strain ellipsoidal analyses, the structural evolution can be grouped into four episodes commenced by the Sorong Fault initiation in the mid-Pliocene and peaked in the Pleistocene time when structures in the Sele Strait took place. Sequential shear-strain ellipsoids show that the Salawati structures evolved and rotated counter-clockwisely in constant magnitude of 25° relative to the present Sorong Fault from the mid Pliocene to the Pleistocene. Sorong Fault tectonism strongly controls the petroleum system of the Salawati Basin.


Authors : Awang H. Satyana, Margaretha E.M. Purwaningsih & Enrico C.P. Ngantung