Blog update #3

I’m getting a bit slack with new blog posts at the moment. The biggest problem I’m having is staying focussed enough to write a small spiel on a single topic. The 34th International Geological Congress in Brisbane last year resulted in a lot of new material relevant to the New England and Northern Rivers areas. So much so that I don’t know where to start!

Looking into the coming weeks (and months) I’d like to provide comments on research by Gideon Rosenbaum on Oroclines of the New England Orogen, Ben Cohen on Cenozoic intraplate volcanism and specifically information on the Main Range Volcanics and its implications south of the Queensland Border, David Branagan on Australias geologist history, plus others.

The above topics are additional to ones I really want to get to as soon as I can such as the Demon Fault, Quaternary sedimentation in the Richmond River Valley, the Tooloom gold fields as well as historical alluvial tin mining in the same area. I need to continue to discuss further aspects of the stratigraphy of the Clarence-Moreton Basin, I also really want to discuss the Mount Warning Central Complex. There just does not seem to be enough time in the day to write about all the geological things this region has to offer.

I'm also pleased that I've been able to be involved, albeit on a mainly strategic level with a local groundwater study, hopefully, in time I'll be able to write something on that... assuming we actually discover something of interest. 

As well as all of the above, the Bigscrub Landcare Group is also about to publish an article which I wrote on the volcanic geology of the region, nice to see how many different groups seem interested in what I'm keen on and are very complimentary about my writing. People are too kind!

Since starting this blog in 2011 I’ve had nearly 25 000 page views. I also vainly ‘google’ a few generic terms and find that the blog frequently comes up quite high in the search results. I’m sort of pleased with that. Of course please feel free to post a comment... especially if I'm wrong about something!

Well… I’ll get started on some more blog posts soon! In the mean time I just want to thank you for reading . I hope that people continue to find it interesting and useful. 

Brown Under and Green on Top

A few months ago I took this photograph at a site I was working on (located mid-way between The Channon and Dunoon). It was a cold spring day with strong cold winds and rain threatening. I love the cold weather, it seems to make you feel more alive! Anyway, I thought it would be a good photo to share since it shows several attributes of our landscape and how  it was formed.

The south side of the valley between The Channon and Dunoon

Firstly the background geology. Where the photo is taken from is on a hill made from rock of the Walloon Coal Measures within a larger steep sided valley. The sides of the Valley are two rock formations more resistant to erosion which is the Miocene aged Lismore Basalt (not visible in the picture) and the Kangaroo Creek Sandstone (Cliffs of which can be in the picture). Here the Lismore Basalt overlies the Late Jurassic aged Kangaroo Creek Sandstone which in turn overlies the Jurassic Walloon Coal Measures. I’ve done some earlier posts which describe the nature of the Kangaroo Creek Sandstone and Walloon Coal Measures, just click on the respective link for more.

Rocky Creek runs through the valley today and it is the action of that creek that formed the valley. The creek must have cut through the lavas of the Lismore Basalt and eventually cut through the Kangaroo Creek Sandstone. Once it was through these hard layers it had an easier task of cutting into the softer and finer grained sediments of the Walloon Coal Measures. It is also possible there is some underlying structural control such as folding or doming but I’m not confident of the extent of this.

The top of the ridge in the photo shows a wet sclerophyll vegetation type, an open forest which contains many Eucalypt species reflecting the Kangaroo Creek Sandstones poor nutrient soils and rapid drainage. Also the ridge is quite exposed to direct sunlight and desiccating winds. Below the cliffs the Walloon Coal Measures start and here is found dry rainforest type vegetation reflecting the better, more nutrient rich and finer grained soils that are developed on the Walloon Coal Measures. The nearby Basalts also have the same vegetation type and in places approach wet rainforest especially in gullys and protected places.

In addition the picture shows the indirect and direct effect of Australians on the environment. The indirect effect is weeds. Many of the bright green trees in the middle of the picture are Camphor Laurel (Cinnamomam camphora) loving the dry rainforest environment. Right in the foreground is Wild Tobacco Bush (Solanum mauritianum) overtaking some of the grazing country. But you will also see a line of dead trees which is part of a successful effort to reclaim the weedy forest into quality native vegetation. The dead trees are poisoned Camphor Laurel with many hectares of forest in this area regenerated by staff working for the local water authority in an ongoing rehabilitation project.

Note that the stratigraphy of the Kangaroo Creek Sandstone has been recently revised since this blog post. See the this post for details.

A geological top 100

There seems to be a proliferation of variation to the theme of 100 things to see before you die. Geotripper did a geologists version back in 2008, it can be found here. Andrew Alden did a review of the list on 1 January which can be found here. I thought they were a little to USA centric so I've modifed theirs to include famous natural features that have a bit more of an Australian favour while maintaining the best ones from around the world. The ones I've managed to do are in bold text 40/100 - what is your score... or what do you want your score to be? Those that you can see in the northern rivers or very close by are underlined.

1. See an erupting volcano
2. See a glacier
3. See an active geyser
4. Visit the Cretaceous/Tertiary (KT) Boundary
5. Observe a river whose discharge is above bankfull stage
6. Explore a limestone cave
7. Tour an open pit mine
8. Explore a subsurface mine
9. See an ophiolite
10. An anorthosite complex
11. A slot canyon
12. Varves
13. An exfoliation dome
14. A large layered igneous intrusion
15. Coastlines along the leading and trailing edge of a tectonic plate
16. See the out of place palm trees of Palm Valley, Northern Territory
17. Stromatolites
18. A field of glacial erratics
19. A caldera (no the Mount Warning “erosion caldera” does not count)
20. A sand dune more than 100metres high
21. Visit a fjord
22. A recently formed fault scarp
23. A megabreccia
24. An actively accreting river delta
25. A natural bridge
26. A large sinkhole
27. A glacial outwash plain
28. A sea stack either an active one or a preserved one 
29. A house-sized glacial erratic
30. An underground lake or river
31. The Great Dividing Range
32. Fluorescent and phosphorescent minerals
33. Petrified trees standing in place
34. Lava tubes
35. The Grand Canyon
36. See a meteor impact crater on a scale that is comprehensible
37. Swim on the Great Barrier Reef
38. The Bay of Fundy, to see the highest tides in the world
39. See a preserved sedimentary dyke (preserved liquefaction from an earth quake)
40. Banded Iron Formations, in the Pilbara, to better appreciate the air you breathe.
41. The snows of Kilimanjaro, Tanzania
42. Lake Baikal, Siberia, deepest lake in the world with 20 percent of the Earth's fresh water
43. Ayers Rock (Uluru), the classic inselberg.
44. See a cliff face of classic columnar jointed lava
45. The Swiss Alps
46. Seeing rock cores being drilled
47. The Li River, China, to see the fantastic tower karst that appears in much Chinese art
48. The Dalmatian Coast of Croatia, to see the original karst
49. The Gorge of Bhagirathi, one of the sacred headwaters of the Ganges, in the Indian Himalayas, where the river flows from an ice tunnel beneath the Gangatori Glacier into a deep gorge
50. Visit Antarctica
51. Climb Mount Warning, one of the most imposing volcanic ‘plugs’
52. Land's End, Cornwall, Great Britain, with fractured granites that have feldspar crystals bigger than your fist
53. Tierra del Fuego, to see the Straits of Magellan and the southernmost tip of South America
54. Visit an active stratovolcano
55. The Giant's Causeway and the Antrim Plateau, Northern Ireland, to see polygonally fractured basaltic flows
56. The Great Rift Valley in Africa
57. The Matterhorn, along the Swiss/Italian border, to see the classic "horn"
58. Visited the Coorong and the lakes at the mouth of the Murray River
59. Stood on the fossils of Maria Island, Tasmania
60. Siccar Point, Berwickshire, Scotland, where James Hutton (the "father" of modern geology) observed the classic unconformity
61. The moving rocks of Racetrack Playa in Death Valley
62. See a lava lake
63. See some the twelve apostles (well, some of them)
64. The Burgess Shale in British Columbia
65. The Channeled Scablands of central Washington
66. See the Pinnacles in Western Australia (or even better, visited Cappadocia in Turkey)
67. Grand Prismatic Spring at Yellowstone National Park
68. Visited (or lived) in an underground house in Coober Pedy
69. The San Andreas fault
70. The dinosaur footprints in Lark Quarry, Winton Queensland
71. The volcanic landscapes of the Canary Islands
72. The Pyrenees Mountains
73. The Moeraki Boulders on the East Coast of Southern New Zealand
74. Denali (an orogeny in progress)
75. A catastrophic mass wasting event
76. Stood at the base of the Bread-Knife, Warrumbungle Mountains
77. The black sand or the green sand-olivine beaches beaches in Hawaii
78. Walk or climb through an Aa lava flow
79. Looked inside The Superpit at Kalgoorlie
80. Visited a waterhole in the Macdonnell Ranges
81. The Tunguska impact site in Siberia
82. Feel an earthquake with a magnitude greater than 5.0
83. See dinosaur footprints in situ
84. Find a trilobite (or a dinosaur bone or any other fossil)
85. Find gold, however small the flake
86. Find a meteorite fragment
87. Experience a volcanic ashfall
88. Experience a sandstorm
89. See a tsunami
90. Witness a total solar eclipse
91. Witness a tornado firsthand
92. Witness a meteor storm, a particularly intense (1000+ per minute) meteor shower
93. View Saturn and its moons through a respectable telescope
94. See the aurora borealis or Aurora Australis, otherwise known as the northern and southern lights
95. View a great naked-eye comet
96. See a lunar eclipse
97. View a distant galaxy through a large telescope
98. Experience a cyclone
99. Burn your shoes on not-quite-cooled lava
100. See the green flash

Do Geologists Fossick? (Happy New Year)

Oh dear, I thought I'd do better than I did in this quiz:

http://geology.about.com/b/2012/12/25/the-2012-christmas-geo-quiz.htm

Andrew Alden put too many tricks in there for me to do very well at all. I'm so ashamed of how badly I won't even share my score!

The answers to the quiz can be found here:

http://geology.about.com/b/2012/12/31/answers-to-the-2012-christmas-geology-quiz.htm

I did however, get question 14 right...

Which of these would professional geologists probably not do: fossicking, frolicking, rimrocking, rocklicking?

When I was actually a professional geologist I would occasionally do some frolicking and almost certainly rocklicking, if I was looking for Uranium (I never got the chance) I might even be doing some rimrocking, but I technically could not be a fossicker. However, since my current profession is a step away from geology I don't consider myself a professional geologist and I can now go fossicking.

Just one of those weird things that has confused my Christmas. Speaking of Christmas, I hope all my readers had a lovely Christmas day. At least you don't have to be a professional to experience Christmas because thankfully Christmas represents a time where everyone who wants to can be freed by the actions of a person on our behalf.

Anyway, happy 2013 to all.