Outback Trip, July 2009

Jani Radebaugh and myself visited some Titan analog sites in the Australian Outback, just before the Geomorphology 2009 conference in Melbourne. We flew to Alice Springs in the center, got a one-way car rental, and drove 2000 miles in 6 days to Adelaide, visiting 2 impact structures, various sand dunes, Uluru, an emphemeral lake, and the rocketry museum at Woomera. Accommodations ranged from the plush Crowne Plaza in Alice, to the old Officer's quarters (now the ELDO Hotel) in Woomera, through an underground hotel in Coober Pedy, to the more spartan dorms at Uluru and a cramped cabin at the William Creek hotel in the middle of nowhere...

Linear dunes near Santa Teresa seen from the air on our Quantas flight in to Alice Springs, showing very Titan-like deviation by mountain ridges. It was this phenomenon that drew us to the area IMG_4321 The Gosses Bluff impact structure, 200km west of Alice Springs. A circular wall of mountains is the remnant of uplifted strata IMG_4353 Shatter cone at Gosses Bluff with my foot for scale. (This striated surface is quite characteristic of large impacts - see some pictures from Canada on my main web page IMG_4375 Self-portrait near the center of the Gosses Bluff structure. Note the near-vertical bedding in the rocks behind me caused by the uplift of the strata beneath the crater (the crater itself has been long eroded away) IMG_4379
Heroic Planetary Scientists in the field (photo by Chris Thorburn) near Santa Teresa, about 200km southeast of Alice Springs. These shallow (and now vegetated) linear dunes squeeze through gaps in the ridge on which we are standing chrisIMG_9413 Chris and Chris (from National Geographic) filming Jani. You fortunately can't see all the flies, which were quite distracting. IMG_4396 Linear dunes meandering as they peter out towards the ridge. The role of wind flow over the ridge, versus possible removal of sand by occasional streamflow at the base of the ridge, remains to be determined. IMG_4410 These tracks are either from a velociraptor (and there are noises at night in the outback that make you think of Jurassic Park...) or perhaps a kangaroo (photo: Jani) 100_9006
View of the rim of one of the Henbury craters. There are about a dozen craters, some tens of meters across : the area bears comparison with the Odessa impact area in Texas. IMG_4436 Upturned beds at the rim, supporting the impact origin (many meteorite fragments have also been recovered in the area). IMG_4439 Remarkably a couple of the craters at Henbury have rays of blocky ejecta. IMG_4443 I try my kite-cam at Henbury (photo: Jani) 100_9077
Uluru (Ayers Rock) - a sandstone remnant. IMG_4467 Uluru takes on dramatic colors at sunset IMG_4484 The only affordable accommodation at Uluru was dorms at the Pioneer Lodge. Their budget dining was fun - $28 for skewers of kangaroo and crocodile, an emu sausage, and a couple of franks. They provide grills for you to cook them yourself. IMG_4496
Tourists ascend Uluru, like ants (photo: Jani) 100_9177 Glutes and quads in action as I start the steep ascent (photo: Jani) 100_9146 340 vertical meters and 40 minutes later we make it to the summit IMG_4525 Uluru and me - note the cavernous weathering and pitting along the beds (photo:Jani) 100_9173
In Coober Pedy, Opal mining capital of the world, we stayed in an underground hotel (a former opal mine) IMG_4543 Trevor of the Old Timers Mine demonstrates extreme aeolian transportation: a large diesel-powered 'blower' sucks the dirt away during opal mining operations - rocks are being pulled out of Jani's hands. IMG_4537 A linear dune beyond a clay pan, east of Coober Pedy. Our trusty Toyota Outlander in the foreground IMG_4560
Edge of Lake Eyre. Wind can cause the waterline to move appreciably since the lakebed, and the water itself, is so shallow. (photo: Jani) 100_9221 Cute self-organized patterns in the salts crystallizing out of the mud at the edge of Lake Eyre IMG_4584 Terraced sediments show that the lake has been higher in the past IMG_4573
Our pilot (Tiania - when not flying at William Creek, she does shark-spotting over beaches near Adelaide) with Jani and the Cessna IMG_4673 Linear dunes from the air. IMG_4663 Near Lake Eyre, some of the 'linear' dunes appear more as chains of crescentic dunes (photo: Jani) 100_9234
Lake Eyre from the air. Note the mirror-like edge of the lake, presumably where the water is so shallow that capillary waves are suppressed. IMG_4606 At the northeast edge of Lake Eyre, linear dunes encroach (or are encroached upon by) the lake. This is something we do not see at Titan... IMG_4632
40km out of William Creek we blew a tire. Jani deftly jacks up the vehicle - luckily we could limp back on our half-sized spare and get it replaced. IMG_4676 Not a repairable flat... A snip to replace at $330 in William Creek, but there was hardly an alternative - nearest sealed roads and proper towns were 200km away (NB even with the 0-deductible rental insurance, windshield and tire damage is not covered :-[ ) IMG_4677
Ralph with the Black Arrow, possibly the worlds most aesthetically pleasing satellite launch vehicle, at Woomera. IMG_4715 After the last leg of the 2000 mile drive, the sun set at the beach in Adelaide, and we flew back to Melbourne for the Geomorphology conference. IMG_4722