Paleomagnetism of the Nakfunu Formation of Early Cretaceous age, Western Tim or, Indonesia

Abstract

A paleomagnetic study has been carried out on deep sea sediments of the Nakfunu Formation of Early Cretaceous age. The sediments have an allochtonous position in the south-central part of Western Timor, Eastern Indonesia. To determine the characteristic remanence samples were partially progressive demagnetized by applying alternating magnetic fields and by heating. The following results were obtained: I = 34.7°, α = 5.7°, which implies a paleolatitude of 19.1°, derived from the mean of 11 sites; and I = 37.8°, α = 8.3° implying a paleolatitude of 21.2°, derived from a selection of the mean of 6 sites. Therefore, the original site of deposition of the Nakfunu sediments must have been 10° south of its present position on the island of Timor. The sediments have moved about 1200 km in a northerly direction since deposition in an oceanic environment, north of the former rim of the Australian continental margin. The remanence carriers in the sediments are both magnetite and hematite.