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This is the Matthew Flinders
Coastal Landform Site, 
part of Flinders 2002 Web


 The 'Investigator'

SOUND

 naval whistle

Site:  Blue Mountains  (NSW)

 

   LANDFORM THEME:  Features of a sedimentary plateau

Over many millions of years thick layers of clastic sediment (sand, silt, mud, clay) and organic materials were deposited in a deep trough, the Sydney Basin, forming mainly sandstone, along with other less resistant sedimentary rocks such as coal, shale and claystone. Much later they were gently uplifted and slightly warped. Subsequent erosion has dissected the plateau, producing deep valleys and leaving remnants of the plateau. Today these remnants are known as the Blue Mountains. 

   FLINDERS THEME:  Matthew Flinders' health at voyage end

   The health of Captain Flinders at the end of the 1801-1803 great voyage of circumnavigation was poor, as also was that of many of the crew. The Investigator, too, was in poor condition. While waiting for his transport back to England, Flinders went to the Hawkesbury settlement (at the foot of the Blue Mountains) to recover. The conditions there were helpful, and he returned to Sydney with his condition much improved. However, the Investigator was condemned as unsound.


   'High mountains, not explored ... Mountains rise to the westward ... supposed courses of the mountain branches of the Nepean ... Canopy Cliff ... The Grose descends in falls and rapids about 400 feet, from Canopy Cliff to its junction with the Nepean ... Caermarthan Mountains'
 - Matthew Flinders' chart



  Parramatta was the first settlement outside Sydney, with others following on the flat, fertile lands in all directions from there. Expansion stopped upon reaching the foot of the Blue Mountains to the west of the Nepean River. This barrier was to remain uncrossed for 25 years after the colony's establishment. 

Flinders' detailed charts, published later, included information (some of which was gathered by others) on the eastern Blue Mountains, visible from the river plain below as a long, steep, north-south running ridge .

  'Hawkesbury River ... R. Nepean ... R. Grose ... Water fresh ... Low lands subject to occasional inundations from the overflowing of the Rivers ... Parramatta'
- from Flinders' Sydney chart

   The features and locations described above are within the Hawkesbury district (where Matthew Flinders went to recouperate in 1803), and are found to the east of what is today called the Blue Mountains. Flinders undoubtedly saw the mountains; they are close by the 'Hawkesbury settlement'.



Extract from Hawkesbury chart

Extract from Flinders' chart
Hawkesbury area to north-west of Sydney
(Note: Hawkesbury-Nepean River in centre, Blue Mountains to west)




   Flinders' friend, George Bass, also possessed a relentless drive for exploration. At one stage, in June 1796, while Flinders was busy with ship maintenance duties in Port Jackson, Bass attempted the land journey that had frustrated many since the earliest years of the Sydney settlement - the crossing of the Blue Mountains. While the expedition had prepared well, it ended in failure against the vertical walls that had also stopped others. Again, another gallant attempt turned back, lacking the correct approach of traversing the ridges (which was not carried out until seventeen years later, in 1813).  



   Health of crew after the circumnavigaton voyage ...
    What were conditions like at the end of the great circumnavigation voyage of 1801-1803? All the men required rest and a number were hospitalised. Much to Flinders' distress, in addition to those lost on the voyage, a number died in Sydney of the lingering results of the disease dysentry, contracted during the voyage. Flinders himself was ill with a different condition that most likely shortened his life. 

Flinders wrote of the interval before departure to England:

    Flinders' illness and recovery 
   'I took this opportunity of making an excursion to the Hawkesbury settlement, near the foot of the black mountains; and the fresh air there, with a vegetable diet and medical care, soon made a great alteration in the scorbutic sores which had disabled me for four months; and in the beginning of July I returned to the ship, nearly recovered.'
- Matthew Flinders in Terra Australis  

go to Flinders   expedition conclusion   activities




   Blue Mountains wilderness 
The Blue Mountains is a vast area to the west, south-west and north-west of Sydney that is largely in natural condition. It is a vital source of water for Sydney, a place of considerable biodiversity, and an escape for people, offering tourism and high quality 'wilderness experience'. Few other cities of Sydney's size (over 4 million) have such a large 'green' area nearby.

 

   Blue Mountains rocks
The rock types are predominantly the sedimentary rocks (sandstones, shale, claystone, coal) of the Sydney Basin. Sandstone makes up the most prominent layers - the spectacular vertical cliffs for which the mountains are famous. Uplift has produced the plateau of the Blue Mountains, while fluvial (running water) erosion has carved deep valleys into this plateau (see photo, above right).  







Photo 1: Plateau edge, valley, Mt Solitary in distance




   Mass wasting
Gravity plays a part in landform change. The process of rapid change through gravity's downwards pull is called mass wasting. Rocks that are weakened, often along joint planes parallel to the cliff face, fall into the deep valleys, forming talus (or debris) slopes. Some rock falls are spectacular; the Katoomba Landslide was predicted, but the fall occured at night when no one was watching.

 

Materials that have fallen from the cliff continue to be weathered into smaller fragments. Eventually soil forms, with hardy plants taking root in this fresh soil. With time (perhaps many decades), a forest cover will have grown over the landslide. Some fragments creep downhill, to be removed by swiftly flowing streams. 





Photo 2: Katoomba Landslide




   Blue Mountains dangers
Physical features, climate and even living things are capable of harming residents of, and visitors to, the Blue Mountains (and other such areas in Australia). Specific dangers warned about on this signboard are fire and rock collapse at the cliff edge (see right). The fire ban sign was most appropriate - just hours later a major fire episode began that lasted for days and caused much destruction! 
 [ Photos taken: 24 Dec 2001 ]

Other potential dangers include hypothermia, heat stroke, dehydration, heart attack and asthma while hiking, snake and tick bite, falls, ankle/knee sprain, and getting lost. These factors add 'spice' to wilderness experience - the Blue Mountains is a place of great beauty and majesty. But it is necessary to be fully prepared when visiting.





Photo 3: Signboard, start of walking track to Pulpit Rock,
near Blackheath



Photo 4: Fires on eastern edge of Blue Mountains,  late Dec 2001


   Blue Mountains fire
Fire, as well as being integral to the natural ecology and the lives of the indigenous inhabitants, appears to be surprisingly active in promoting landform change on sandstone. Wildfire, on average, passes over a typical area of the Blue Mountains about every 10 - 20 years. The heat of its initial passing causes expansion, and combined with later contraction, the surface rock may flake to a depth of up to 2 cm due to weakened particle binding. In addition, the surface, devoid of vegetation, is more vulnerable to erosion during later rains. Smouldering tree stumps, which may remain hot for days, are believed to cause adjacent rock heating to even greater depths for longer periods of time, thereby causing more intense disruption to particle binding (but over smaller areas on average).

 



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(photo button above: Grose Valley panorama)

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For further information


LANDFORM LINKS
Blue Mountains NP: Geology & Landforms
Sedimentary Case Study - Blue Mountains, NSW
Year 5 Class Geology Page: Blue Mtns
Blue Mountains for Kids
Hawkesbury River - Primary School Web Page
Sandstone (rock type of much of Blue Mountains)
For Comparison: Grand Canyon (USA) - sedimentary plateau
For Comparison: Grand Canyon Explorer


ENVIRONMENTAL LINKS
Blue Mountains NP Map
The Wollemi Pine (Dinosaur Tree)
Fire & the Australian Landscape
Walk in the Blue Mountains: Mt Banks


PEOPLE LINKS
Blue Mountains Aboriginal Heritage
Glenbrook Attractions       Blue Mountains Web
Stone Wall Building in the Blue Mountains



Printed Materials

 Pickett J.W. & Alder J.D. - Layers of time: the Blue Mountains and their geology
 NSW Department of Mineral Resources, Sydney. 1997


White, M.E. - Running Down: Water in a Changing Land
Kangaroo Press, East Roseville NSW. 2000


Mosley, G. - Blue Mountains for World Heritage
Colong Foundation for Wilderness, Sydney. 1989

Reader's Digest Scenic Wonders of Australia
 Reader's Digest, Surry Hills NSW. 1976


Branagan,D. & Packham,G. - Field Geology of New South Wales
 Science Press, Sydney. 1967


Mackaness, G. - Fourteen Journeys Over The Blue Mountains of NSW: 1813-1841
Horwitz-Grahame, Sydney. 1965


and  Matthew Flinders  Books


Site / Photos (c) C.Grant 2002, 2003