Sunda Trench an underwater ridge, and much of the trench is at least partially filled with sediments. Mappings after the 2004 Indian Ocean earthquake of the plate boundary showed resemblance to suspension bridge cables, with peaks and sags, indicative of asperity and locked faults, instead of the traditional wedge shape expected. Some of the earliest exploration of the Trench occurred in the late 1950s when Robert Fisher, Research Geologist at the Scripps Institution of Oceanography, investigated the trench as part of a worldwide scientific field exploration of the world's ocean floor and sub-oceanic crustal-structure. Bomb-sounding, echo-train analysis and manometer were some of
Capture of Regina Trench The left-hand battalion was stopped in front of the trench with many casualties and the brigade withdrew at nightfall. A few troops of the right-flank battalion of the 9th Canadian Brigade, 3rd Canadian Division got into Regina Trench through some German sally ports but was overwhelmed. The battalion on the left flank, reached Regina Trench at the junction with Courcelette Trench but was then forced back. Part of the 7th Canadian Brigade reached Regina Trench, began to bomb westwards and also worked up the West Miraumont road but was eventually forced back by German counter-attacks. The left hand battalion was