14- Laos-Vietnam Karst Reconnaissance
December 7 and 8, 2011
Lan Ha Bay is the southwestern extension of Ha Long Bay, just east of Cat Ba Island, Vietnam. A major karst reference work is the report by Tony Waltham, 2005:http://www.speleogenesis.info/directory ... df9536.pdf
Still drizzly, overcast, and cool but with good visibility across the drowned karst.
We chartered (rather by accident) a wooden sailing Junk built over 30 years ago as a working fishing vessel, that was refitted as a tourist boat about 4 years ago. The fish hold has morphed into a rather nice cabin, and it is still capable of quietly going about its business under sail. The big diesel is there for calm days or forcing your way against unfavourable winds. I have been told that it is the only real sailing tourist boat at Cat Ba Island, and that seems correct. All the other tourist boats have fake masts. Clearly they would capsize should they ever actually try to set the sails that none of them carry.
Additionally, this is clearly a unique vessel on the waters of Lan Ha Bay as every tourist boat we pass is suddenly lined with tourists taking pictures of us. The captain is a grizzled Vietnam fisherman of uncertain age who certainly knows well the many least-travelled parts of the bay.
Ha Long Bay is definitely over touristed - this part around Cat Ba is much less so, especially if you glide into waters not routinely visited by the tourist boats from the north of Ha Long Bay. We towed two two-person kayaks behind us.
We explored a number of sea-level caves that connect to interior lagoons - drowned dolines. Some you can see through but other connecting caves bend and twist and require good headlights to safely traverse.
It requires good knowledge of the caves and tides, as very strong, rapidly-changing currents occur as the tide pushes water into, or sucks it out of, the interior lagoons. The tidal zone is heavily populated with clams which the local fisherman hammer open to collect the meat inside. The broken shells are razor sharp - like a mini-security wall heavily topped with concrete and broken glass. One touch and you are likely to be seriously bloodied. A real hazard to someone in a kayak reflexively fending off the cave wall.
An obligatory stop at Song Sot commercial cave - the "best' tourist cave in the bay. It is a high-level remnant of a large trunk conduit that passes clear through the island - it was clearly all that is left of a major trunk cave and passes completely through the island. It is large and although well decorated, is dry and dusty and the formations have long lost their luster. Tourists wander freely off the trail. Never-the-less, it is worthwhile as the electrical lighting lets you see the large dimensions of the cave.
There is a U-tube video of Hang Sung Sot:http://www.youtube.com/watch?NR=1&featu ... ia-pZQ41yg
A night on the junk floating in a quiet baylet far from the other tourist boats partying far out of earshot.
8/12/2011 Wed - Lan Ha Bay
More exploration of the bay and caves, in part finding the places that Tony Waltham wrote up in his geologic report. It is wonderful to have the freedom to say "go over there!" I am learning how to get to interesting and instructive karst features that will be of much greater interest to the caver and karst scientist than those you would see by taking a standard tourist trip. No matter though, as the bay is simply stunning and it is beautiful and inspiring everywhere.
Back at Cat Ba this evening, after another great seafood dinner.
DirtDocFrequent Poster Posts: 58Joined: Wed Sep 28, 2005 11:23 amLocation: Denver, CO