Mountains Of the Corella Valley (North West Queensland's Argylla Ranges, Outback Australia)

            The Corella Formation between Cloncurry and Mary Kathleen, northwest Queensland, was later modified (metamorphosed) by moderately high temperatures, and as a result, calcium-rich silicate minerals like hornblende, diopside and scapolite crystallised. The resulting rocks are known as calc-silicates. Crustal forces also compressed them to generate spectacularly folded, layered rocks typical of the formation. The Quilalar Formation of the same age northwest of Mount Isa was not modified by such high temperatures.

The idea that these limestones, dolomites and other sediments formed in a hyper-saline sea comes from the widespread scapolite in them. This is a complex metamorphic mineral which requires abundant sodium, chlorine, and sulphate to crystallise - these are abundant in hyper-saline water.

As well as being metamorphosed, the Corella Formation was extensively permeated by hot fluids rich in sodium, potassium, and iron. This metasomatism resulted in the growth of reddish feldspars (albite and microcline) and iron-rich silicates such as epidote and amphibole, as well as additional scapolite. The fluids causing this 'red-rock alteration' are regarded by many geologists as a necessary precursor for the formation of the iron-oxide-copper-gold deposits which occur in the Cloncurry region.

Around Cloncurry, parts of the Corella Formation have been broken up to form a breccia (blocks of the original rocks mixed erratically in a matrix of finer material). The cause of the breccia remains uncertain but seems to be a process which post-dates the laying down of the rocks. During deformation and metamorphism, some layers will react differently to the strain, some being brittle and others being more plastic, and this contrast can lead to breaking of the more brittle layers. Other ideas are that it formed by a process called hydraulic fracturing by fluids escaping from later granite intrusions or by gases from deep in the crust. Either way, the breccia is a widespread but enigmatic rock type.

Source: Rocks and Landscapes of Northwest Queensland by Laurie Hutton & Ian Withnall.

Taken on: January 1, 2022

Tags:

bush

bushland

formation

rock formation

mountain

mountains

rock

rocks

stone

stones

cliff

cliffs

field

fields

sky

skies

tree

trees

bird

birds

bug

bugs

animal

animals

marsupial

marsupials

breeze

wind

rains

rainy

cloud

cloudy

clouds

nature

natural

native

wilderness

wild

aboriginal

indigenous

kalkadoon

european

europeans

people

peoples

history

historic

heritage

outback

corella valley

argylla ranges

ballara

mount isa

cloncurry

north west

queensland

australia « less

Sets appears in: • North West Queensland (Kalkadoon/Mitakoodi Country)

Groups appears in: • Flickr Nature • Your photo goes here! no 30/60 more » • Queensland • Your Best Photography • Panorama Maker • Nature...Anything Goes • nature's composition • Panoramas - Panoramiques • Land of Oz (This is Australia!) • Western Queensland • The Hundred Club of Flickr • Queensland Australia • Outback of Australia • Queensland Photographers Australia • Photography Week • World Photographers' Photos WPP • Landscapes Only • Your best of the best • The Best ... • ㋡ flickr ○● DEPOT ㋡ • This is Why I Bought A Camera • Nature and Animals (Wild Only) • Pictures of the World. • The best picture of the world • Australia, Our Great Southern Land • The best photographs from around the world. • wildlife and the wild « less

Camera: Nikon D5600, f/9.0, 1/160 sec, 25mm (=37mm), ISO 100 (more info) (hide info)

Camera:	Nikon D5600
Lens:	TAMRON 17-35mm F/2.8-4 Di OSD A037N
Aperture:	f/9.0
Exposure Time:	0.006 sec (1/160)
Focal Length:	25mm (35mm equivalent: 37mm)
ISO:	100
Exposure Bias:	0 EV
Flash:	Off, Did not fire
Exposure Program:	Manual
Exposure Mode:	Manual
Metering Mode:	Multi-segment
White Balance:	Auto
Saturation:	Low
Sharpness:	Hard
Color Space:	sRGB
Software:	Adobe Photoshop Lightroom Classic 11.3.1 (Windows)
Show full info

Stats: 969 views / 2 comments

Link to this photo view:
Link to this photo large view: