08-Feb-2008 -- We visited 22N 54E on the 2nd day of a 500+ km off-road tour of the Rub` al-Khāliy dunes and sabkha. Twenty four hours later, we came very close to 22N 55E (within 2.7 km), but we prudently turned back from this elusive dune top confluence due to time constraints.
Our route for our 5-day outing was planned using Google Earth images to try to find the relatively less difficult routes across dozens of huge, complex star dunes and interspersed sabkhas (dry lake beds). Thirty eight way-points were designated along our chosen route as navigational land marks, and loaded to the GPS's carried in the 7 participant vehicles. Navigation whilst driving was established by Dell laptop computer with OziExplorer GPS mapping software in moving map mode with NASA landsat images and Garmin GPS.
Our travels began with an 800 km tarmac ride from Ẓahrān to our final gas stop at Šayba. We then crossed another 52 km of Šayba Field rig roads, before our off-road departure at ~1 p.m. On Thursday afternoon, 7 February, we drove 55 km, with 2:23 hrs moving time, and camped 12.7 km from the Confluence. On Friday morning, 8 February, we departed at 7:30. We made good progress with fast travel along the sabkhas, and southerly navigation across the dunes. We took advantage of several opportunities for sandboarding down the ubiquitous slip-faces often more than 200 ft high. We were startled and amazed to hear, and feel, a very loud resonant low frequency thunder-rumble caused by loose dry sand avalanching down the dune slip-face as we descended the slope on our sandboard, in vehicles, or on foot. We arrived to the Confluence at 10:55. Several of our GPS's showed uncertainty of 3 m (Garmin Trek), 4 m (Garmin 60c), and 9 m (Garmin 273C and Garmin V) on their display; this uncertainty was also born out in the zero point location of each GPS, which varied along the east-west direction with location differences of 1 to 3 meters.
After taking the requisite pictures and some group shots, we continued our travels easterly towards 22N 55E. On Friday and Saturday we experienced some significant delays associated with getting stuck, loosing tire beads, and tipping one of our vehicles on its side. We were very pleased to visit the magnificent dunes of Rub` al-Khāliy in the vicinity of these two Confluences.
Video clips from this trip are here.
Continued on 22N 55E.