Abstract
In recent years, there has been a considerable expansion of deployments of portable seismic
stations across Australia, which have been analysed by receiver function or autocorrelation
methods to extract estimates of Moho depth. An ongoing program of full-crustal reflection
profiles has now provided more than 25 000 km of reflection transects that have been interpreted
for Moho structure. The Moho data set is further augmented by extensive marine reflection
results. These new data sources have been combined with earlier refraction and receiver
function results to provide full continental coverage, though some desert areas remain with
limited sampling. The dense sampling of the Moho indicates the presence of rapid changes
in Moho depth, and so, the Moho surface has been constructed using an approach that allows
different weighting and spatial influence depending on the nature of the estimate. The inclusion
of Moho results from continental-wide gravity inversion with low weighting helps to resolve
the continent-ocean transition and to provide additional control in the least sampled zones.
The refined distribution indicates the presence of widespread smaller-scale variations in Moho
structure. Strong lateral contrasts in crustal thickness remain, but some have become more
subdued with improved sampling of critical areas. The main differences from earlier results
lie in previously poorly sampled regions around the Lake Eyre Basin, where additional passive
seismic results indicate somewhat thicker crust though still with a strong contrast in crustal
thickness to the cratonic zone to the west.
stations across Australia, which have been analysed by receiver function or autocorrelation
methods to extract estimates of Moho depth. An ongoing program of full-crustal reflection
profiles has now provided more than 25 000 km of reflection transects that have been interpreted
for Moho structure. The Moho data set is further augmented by extensive marine reflection
results. These new data sources have been combined with earlier refraction and receiver
function results to provide full continental coverage, though some desert areas remain with
limited sampling. The dense sampling of the Moho indicates the presence of rapid changes
in Moho depth, and so, the Moho surface has been constructed using an approach that allows
different weighting and spatial influence depending on the nature of the estimate. The inclusion
of Moho results from continental-wide gravity inversion with low weighting helps to resolve
the continent-ocean transition and to provide additional control in the least sampled zones.
The refined distribution indicates the presence of widespread smaller-scale variations in Moho
structure. Strong lateral contrasts in crustal thickness remain, but some have become more
subdued with improved sampling of critical areas. The main differences from earlier results
lie in previously poorly sampled regions around the Lake Eyre Basin, where additional passive
seismic results indicate somewhat thicker crust though still with a strong contrast in crustal
thickness to the cratonic zone to the west.
Original language | English |
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Article number | ggad035 |
Pages (from-to) | 1863–1877 |
Number of pages | 15 |
Journal | Geophysical Journal International |
Volume | 233 |
Issue number | 3 |
DOIs | |
Publication status | Published - Jun 2023 |