GSA Guide – Geological Outcrop, Kurilpa Bridge area Claimed

Geological Outcrop, Kurilpa Bridge area

A well known fault structure defined by a straight stretch of the Brisbane River.

Kurilpa Bridge

Outcrop under the Riverside Expressway.

Steeply dipping rocks along Normanby Fault.

Normanby Fault - Brisbane River straight stretch.

History:

The image shows the Riverside Expressway and the later constructed bicycle and river walkway to Toowong, the University of Queensland, and the southwest of the city.  The bikeway is part of an extensive network of bicycle routes around the CBD and the Brisbane City Council area.

The Expressway was constructed after the Wilbur Smith Report completed in 1970 looked at Brisbane’s future infrastructure needs.  Expressways were proposed for both sides of the river, but only the northern one was constructed. 

Given that South Bank and South Brisbane have been inundation by most of the floods since Brisbane was founded in 1825, it seems much of this land would have been better used as a transport corridor.

Geology:

The rocks comprise variably weathered, grey to medium brown argillite of the Neranleigh-Fernvale beds, which formed as sediments deposited in a deep trench off the edge of the continent in the Late Devonian and Carboniferous, between 370 and 315 million years ago. 

These rocks which underlie large parts of south east Queensland were subject to intense compression, folding and uplift to form mountain belts in Triassic times (around 265 to 235 million years ago).

The images above taken from the Kurilpa Bridge show the Gallery of Modern Art (GOMA) and the Brisbane Eye to the east, and the William Jolly Bridge with Mount Coot-tha (in the background) to the west.

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