Map Showing Estimated Uncertaninty Region (IMAGE) Curtin University Caption This is a map showing estimated uncertainty region (yellow box) for the source of the signals shown in Fig. 1. Magenta points and text show the locations of the various recording stations. RCS is the IMOS recorder west of Rottnest Island, HA01 is the CTBTO station off Cape Leeuwin, and HA08S is the southern CTBTO BIOT/Chagos Archipelago array. The fix was calculated using data received at RCS and HA01. The signal was not received at HA08S which could be due to it being blocked by shallow water to the north or northwest of this station or poor coupling of the signal into the Deep Sound Channel due to an unfavorable seabed slope. Credit Curtin University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.