The Geology of Portuguese Timor

Abstract

This thesis is an account of the stratigraphy and structure of Portuguese Timor (an area of. 16,000 sq. km.) supported by four geological maps (1:100,000).. Twenty four formations are distinguished, four of' which are allochthbnous. The autochthonous formations range in age from Lower Permian to Recent, and make up a section of 8000 metres thickness.Of the allochthonous formations one is pre-Permian, two are Permian, and the other a midMiocene gravity slide deposit. The lithology and petrography of each formation is described, the fauna and flora recorded, and the environment of deposition discussed.As limestones are the predominant rock type in Timor special attention has been paid to limestone petrography.Five separate periods of folding are recognised, two of which, the Timorean and the Ramelauean, were of major importance and accompanied by large scale overthrusting.

Ground Surface Deformation Detection in Complex Landslide Area—Bobonaro, Timor-Leste—Using SBAS DInSAR, UAV Photogrammetry, and Field Observations

“…Timor is a non-volcanic island located between the south-eastern part of the Indonesian archipelago and the northern part of the Australian continent [55]. It is approximately 500 km long and 100 km at its greatest width, elongated in the SW-NE orientation.…”

Provenance of Permian–Triassic Gondwana Sequence units accreted to the Banda Arc in the Timor region: Constraints from zircon U–Pb and Hf isotopes

“…The Maubisse Formation consists of a distinct red, crinoidal limestone, shale and volcanic rocks that were deposited mostly during the Permian with ages ranging from latest Pennsylvanian to Triassic, and represents the oldest rocks exposed in the Banda Orogen (de Roever, 1940;Audley-Charles, 1968;Davydov et al, 2013). Pillow lavas found within the Maubisse Formation have geochemical signatures of within-plate and ocean-ridge basalt, which is interpreted as representing the onset of rifting (Berry and Jenner, 1982).…”

“…Evidence for this bimodal magmatic event is seen in the Gondwana Sequence where minor amounts of rhyolite and granite are accompanied by larger volumes of alkali basalt (Audley-Charles, 1968;Wopfner and Jin, 2009). These compositions typify continental rifting events (McKee, 1970).…”

“…2). Pre-and syn-breakup strata below the unconformity formed during the Pennsylvanian to Jurassic while Australia was part of Gondwana and are known as the Gondwana Mega-sequence (Audley-Charles, 1968;Harris et al, 2000;Haig et al, 2008). The Australian Passive Margin Mega-sequence overlies the unconformity.…”

“…Other studies of these rocks include: Simons (1939), Gageonnet and Lemoine (1958), Audley-Charles (1968), Gianni (1971), Grady and Berry (1977), Charlton (1989), Bird and Cook (1991), Hunter (1993), Barkham (1993), Sawyer et al (1993), Prasetyadi and Harris (1996), Harris et al (1998Harris et al ( , 2000Harris et al ( , 2009, Charlton (2002), Charlton et al (2009), Vorkink (2004, McCartain and Backhouse (2006), Kaneko et al (2007), Zobell (2007), Haig et al (2008), and Major (2011). From these studies it is evident that Gondwana Mega-sequence units exposed in the Banda Collision and drilled offshore on the Australian margin are best divided into two series, the Permian-Triassic Aileu-Maubisse Series, and the Permian-Jurassic Kekneno Series (Lemoine, 1959;Audley-Charles, 1968;Rosidi et al, 1981;Sawyer et al, 1993). The stratigraphic relationship between the two series is ambiguous due to the fact that in most places the Aileu-Maubisse series is thrust over the Kekneno Series.…”