Jennifer Marohasy

a forum for the discussion of issues concerning the natural environment

Know Your Environments?

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Guess where I took this photograph… and what the rock formation shows?

Sunday Update.

The answer: Fan Rock, Capricorn Coast, Queensland with the rock formation showing the inside of an extinct volcano including the lava tube.

 

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Comments

  1. William Martin says

    off topic but I tried to view the Bill Kininmonth on TV link (with Kerri-anne).
    I then received a “malicious adware has terminated windows explorer” message !

  2. Avatar photojennifer says

    Hi William, The link doesn’t appear to link to that program anymore, but I don’t get a malicious adware message.

  3. Luke says

    Wild guess #1 Organ Pipes Nat Pk, Victoria

    similar geology to Sawn Rocks, Narrabri but with some folding ?

  5. Jaymez says

    I’ll go out on a limb. Limestone on a coastal cliff showing previous sea levels? It reminds me of cliffs near Port Arthur Tasmania, but the foliage and lichen suggests it is no longer seafront – more inland. maybe Kuringai Chase, or even the Grampians?

  6. Johnathan Wilkes says

    Luke
    Unless I missed some parts of the Organ pipes area, I’d rule it out for sure.
    I don’t think it’s the same geology.

  7. RexAlan says

    Some type of Basalt?

    A bit like the Giants Causeway in Northern Ireland except it’s horizontal not vertical.

    Wouldn’t have a clue as to where the photo was taken though.

  8. ianl8888 says

    “similar geology to Sawn Rocks, Narrabri but with some folding ?”

    The Narrabri exposure is sedimentary

    Folding is a diagnostic of metamorphism

  9. william martin says

    I don’t know where it is, but I’m willing to try some observations.
    I don’t think it’s a high rainfall area, judging from the height of the trees. The lichen might indicate that the area receives mist or cloud. There is no sign of bird-life. The cliff is moderately worn, so it isn’t an ancient formation, like the Flinders or Gammon Ranges. I assume the wind is westerly and the ravine is facing south. I don’t see much water erosion, so I’m thinking the area is in a rain shadow, not near the coast. The erosion looks more due to thermal conditions, rather than water.
    I’m guessing it’s within a day’s drive east of where you live Jennifer !
    Just a wild guess ! And please be gentle – a geo-morphologist I (obviously) am not !

  11. Les Johnson says

    Sedimentary rock, probably limestone (light colored rock), with a possible vocanic intrusion (dark rock).

    Definite deformation and folding of the limestone in the bottom right, indicating techtonic movement. (Metamorphism can occur to sedimentary rock, too. For example, limestone becomes marble.)

    The uniform thickness of each layer indicates a change of climate at each interface. The thicker light layers were laid down in warm water. The thin layer between each light layer probably indicates short periods of colder weather. The uniform thickness of each layer suggest a regular time period for each layer. This could be decadal or even annual.

  14. william martin says

    Okay Jennifer, not Waa Gorge, but somewhere in Mount Kaputar National Park, maybe Mount Kaputar. The park “consists of sharp peaks and rocky ranges, the remnants of a 17 million year old volcano. the peak of the range is Mount Kaputar, which reaches an altitude of 1510 metres. From the summit you can take in 360 degree views encompassing one tenth of New South Wales.” (google earth)
    I’m thinking you were pressed for time when you took this pic, on your way back from a cereal crop.

  15. Avatar photojennifer says

    Let’s stay civil and friendly (towards this end I’ve tidied one or two of the above comments).

    The photograph was taken in Central Queensland within 150km radius of Rockhampton.

    And a big hint: the rock is igneous.

  16. Les Johnson says

    Igneous and layered so evenly? I would never have believed it.

    Don’t keep us hanging, Jennifer….

  19. william martin says

    “In the Rockhampton region, three stratigraphic units are recognized: the Early Devonian Mt Holly Formation and the Middle Devonian Capella Creek and Barmundoo Formations, with the Mt Morgan Tonalite (Late Devonian) considered as part of the assemblage.” Australian Journal of Earth Sciences.
    Thanks for the learning experience Jennifer. It’s been a great night.

  22. Avatar photojennifer says

    Luke has it.

    The picture was taken at Fan Rock on the Capricorn Coast. It shows the inside of what was a volcano with the lava tube extending up vertically in the right side of my picture.

    And the even layering is because the lava flow cooled, shrunk and cracked like a slab of mud.

  24. Larry Fields says

    Speaking of lava tubes… There are some nice ones in Coconino National Forest, on Arizona’s Kaibab Plateau, West of Flagstaff. Yes, you can drive there. As of 1975, the one with which I was most familiar was in Patrol Area 331.

    Another one further West is a long loop, whose two entrances are quite close to each other. Even if I were a geologist, it’d be difficult to guess how that came to pass.

  26. John Sayers says

    how about this farmer!!

    “Murray mouth cattle and grain farmers Colin and Sally Grundy, who are angry their river water is too salty for irrigation, said they would be disappointed if the diversion limit were not changed from the recommendation.

    While welcoming the proposed salinity targets, the couple, who have 1000 cattle on their Mundoo Island property opposite the mouth of the Murray, had hoped the MDBA recognised the desperate need for greater environmental flows.

    “At the moment even 2750GL isn’t good enough – the bottom of the Coorong isn’t covered and the Chowilla floodplains in the riverland aren’t covered,” Mr Grundy told The Australian”

    http://www.theaustralian.com.au/national-affairs/state-politics/undiluted-murray-plan-leaves-states-cold/story-e6frgczx-1226368776295

  28. John Sayers says

    Gavin – I recognise the Murray Mouth farmer – does he recognise that he’s in a naturally saltwater environment yet he expects the rest of the upper basin to sacrifice their water so he can be sustainable??

  29. Avatar photojennifer says

    Thanks John. Just posted on it…

    THIS morning our national newspaper, The Australian, has a very misleading story about a farmer Colin Grundy complaining that Murray river water is too salty for irrigation. [1]

    In fact Mr Grundy does not live anywhere near the Murray river. He lives right beside the sea.

    Mr Grundy lives on Mundoo Island that faces the Murray’s sea mouth that is a narrow outlet to the pounding surf of Encounter Bay and the Southern Ocean.

    Reporting on water quality in the Murray River with reference to Mundoo Island is like reporting on water quality in the Parramatta River from Circular Quay in Sydney Harbour, or water quality in the Brisbane River from Fisherman’s Island at the mouth of the Brisbane River.

    There is a sea dyke across the Mundoo channel to hold back the tides of the Southern Ocean but last autumn the Southern Ocean did splash over the top of it.

    Upstream, in the Murray River proper, salinity levels are at historic lows. [2]

    More here: http://jennifermarohasy.com/2012/05/more-nonsense-in-national-news-about-murray-darling/