Multitaper coherence method for appraising the elastic thickness of the Indonesian active continental margin

Abstract

We estimate the mechanical strength of the Indonesian active continental margin. Values of effective elastic thickness (Te) were obtained for azimuthally averaged coherence measurements γ 2 ( | k | ) between Bouguer gravity and topography using a multitaper method with Hermite tapers. The T e estimates reveal uniform low strength (4–7 km) beneath the entire Indonesian continental margin. The 2D coherence function γ 2 ( | k | ) estimated with the help of MTM reveals varying anisotropy in the Indonesian margin and illustrates how the results correlate with the maximum horizontal stress orientations (SH max), heat flow measurements, sediment thickness and shear wave speed measurements. The sediment thickness and heat flow in these regions do not appear to influence the strength of the Indonesian margin. We have inferred that low effective elastic thickness could have been fossilized on a much younger oceanic plate at the time of loading.