I am a National Geographic archaeologist following up on an earlier post: curses, snakes, robots, weird discoveries--ask away!
I'm Dr. Fred Hiebert, National Geographic archaeologist and explorer, back at National Geographic headquarters to answer more of your questions. See my IAmA from last September, when I was in Kyrgyzstan looking for the underwater remains of an ancient palace: http://sc.reddit.com/r/IAmA/comments/10701n/iama_national_geographic_archaeologist_currently/
Besides sunken palaces on the Silk Road, I've also searched for Genghis Khan's tomb in Mongolia [http://exploration.nationalgeographic.com/mongolia/expedition], found lost treasure in Afghanistan [http://www.nationalgeographic.com/mission/afghanistan-treasures/], worked with Bob Ballard (discoverer of the Titanic) in the Black Sea [http://www.nationalgeographic.com/blacksea/ax/frame.html], and searched for sunken temples in Lake Titicaca [http://news.nationalgeographic.com/news/2001/06/0604_boliviashrines.html].
UPDATE: Thanks everyone for another wonderful AMA. I'll try to answer additional questions within the next day or so.
UPDATE: I'll be live today 2/13 from 630-730 pm EST to answer more questions- if I haven't answered your question, I probably already answered a similar one- check out the table here: http://newyork.craigslist.org/que/for/3615562282.html
UPDATE: Another great session- thanks everyone!