Morphostructural mapping of the Manamas Mountain, a Banda Arc fragment overthrusting on the Australian Continental Margin (Oecusse, Timor-Leste)

Abstract

<p>Timor island is located north of Australian Continent and is one of the southeasternmost Sunda islands. In a tectonic context, is located at the collisional margin between the oceanic Banda volcanic arc and the Australian continental margin. The island does not have a volcanic nature and is made up of three main tectonostratigraphic sequences : i) Australia Affinity Sequence, that comprises units whose ages range from the Upper Carboniferous to the Late Miocene, deposited on Australian continental or transitional continental crust prior to collision with the Banda Terrane; ii) Banda Arc Terrane Sequence, that comprises the allochthonous forearc units of the Banda volcanic arc and are of Asia affinity. They span from Jurassic to Pliocene in age; iii) Banda Orogen Sequence, consisting of units that have formed or been deposited since the start of collision of the continental margin with the Banda forearc, ages spanning from upper Miocene to present.</p><p>The Manamas Mountain is an elevated region located in the northeast sector of the Timor-Leste Oecusse enclave, largely built up of volcanic rocks of Late Miocene age (Manamas Formation; Banda Arc Terrane Sequence). It may represent a fragment of the Banda Arc overthrusting on the northernmost edge of the Australian continental margin.</p><p>Recognition of the main structural lineament systems of the Manamas Mountain and definition of its main morphostructural characteristics to complement structural and geological mapping are the main goals of the present study, which aims to determine such aspects through interpretation of spatial remote detection digital data acquired by the Landsat satellite's sensor (ETMþ) and the Earth satellite's sensor (Aster) and aerial orthophoto maps.</p>