The Lake Edgar Fault in Western Tasmania, Australia is marked by a prominent fault scarp and is a recently reactivated fault initially of Cambrian age. The scarp has a northerly trend and passes through the western abutment of the Edgar Dam, a saddle dam on Lake Pedder. The active fault segment displaces geologically young river and glacial deposits. It is 29 ± 4 km long, and dips to the west. Movement on the fault has ruptured the ground surface at least twice within the Quaternary and possibly the last ca. 25 000 years; the most recent rupture has occurred since the last glaciation (within the last ca. 10000 years). This is the only known case of surface faulting in Australia with evidence for repeated ruptures in the Late Pleistocene. Along its central portion the two most recent surface-faulting earthquakes have resulted in about 2.5 m of vertical displacement each (western side up). The Lake Edgar Fault is considered capable of generating earthquakes in the order of magnitude 6 1/2-7 1/4. The Gell River Fault is another fault nearby that was apparently also active in the Late Pleistocene. It has yet to be studied in detail but the scarp appears to be more degraded and therefore older than the most recent movement on the Lake Edgar Fault.

Item Type:	Refereed Article
Research Division:	Earth Sciences
Research Group:	Geophysics
Research Field:	Seismology and Seismic Exploration
Objective Division:	Expanding Knowledge
Objective Group:	Expanding Knowledge
Objective Field:	Expanding Knowledge in the Earth Sciences
Author:	Jensen, V (Mr Vagn Jensen)
ID Code:	28142
Year Published:	2003
Web of Science® Times Cited:	3
Deposited By:	Earth Sciences
Deposited On:	2003-08-01
Last Modified:	2004-03-16
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