Three-dimensional admittance analysis of lithospheric elastic thickness over the Louisville Ridge

Hongtao Hao,Minzhang Hu,Hui Li,Lelin Xing,Chongyang Shen

doi:10.1007/s11589-016-0147-2

Hongtao Hao, Minzhang Hu + Show 3 more

Open Access

https://doi.org/10.1007/s11589-016-0147-2

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Journal: Earthquake Science	Publication Date: Apr 1, 2016
Citations: 11	License type: CC BY 4.0

Affiliation: China Earthquake Administration

Abstract

Using bathymetry and altimetric gravity anomalies, a 1° × 1° lithospheric effective elastic thickness (T e) model over the Louisville Ridge and its adjacent regions is calculated using the moving window admittance technique. For comparison, three bathymetry models are used: general bathymetric charts of the oceans, SIO V15.1, and BAT_VGG. The results show that BAT_VGG is more suitable for calculating T e than the other two models. T e along the Louisville Ridge was re-evaluated. The southeast of the ridge has a medium T e of 10–20 km, while T e increases dramatically seaward of the Tonga-Kermadec trench as a result of the collision of the Pacific and Indo-Australian plates.

Highlights

As a seamount chain, it is exceeded in size only by the Hawaiian-Emperor Chain, little is known about the tectonic settings of the Louisville Ridge because of its remote location
The bathymetry around a seamount is predicted using high-resolution gravity anomalies derived from Geosat altimetric data for different Te
A 1° 9 1° Te model is calculated over the Louisville Ridge and the adjacent regions

Summary

Introduction

As a seamount chain, it is exceeded in size only by the Hawaiian-Emperor Chain, little is known about the tectonic settings of the Louisville Ridge because of its remote location. Lyons et al (2000) tried to reconcile these results and introduced a 3D ‘‘bathymetry-predicting’’ method to estimate Te. According to Cazenave and Dominh (1984), Te increased from southeast to northwest, while Watts et al (1988) found the opposite trend. Lyons et al (2000) tried to reconcile these results and introduced a 3D ‘‘bathymetry-predicting’’ method to estimate Te In this method, the bathymetry around a seamount is predicted using high-resolution gravity anomalies derived from Geosat altimetric data for different Te. The predicted bathymetry is compared with in situ ship soundings. The results of Lyons et al (2000) tend to agree with those of Cazenave and Dominh (1984) with respect to trend, showing increasing values from southeast to northwest

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