(3N) Namakdan Cave

(3N) Namakdan Cave , The world's longest cave in salt (6580 m.)

In Farsi, the word "namak" means salt. Or Sodium Chloride, as ordinary kitchen salt is known among chemists. And it is salt, or namak, that Namakdan Mountain on Qeshm Island in the Persian Gulf is made of. Nine years ago the Czechs were the first to venture further into the caves than the entrance. They discovered a complex system of caverns and tunnels and have been returning ever since.



The 3N Cave and related Upper Entrance Cave are developed in the SE part of Namakdan Salt Diapir in western part of Qeshm Island (Fig.1).
The 3N Cave consists of one large meandering passage opened by entrance (8 by 2 m) in the western wall of outlet valley (Fig.2). This lower entrance is partly filled by brine. Another large lake, 300 m long and up to one metre deep was developed at 160 m from the entrance behind small collapse dam between 1999-2004. The lake was dry in spring 2005, as well as this year, as the dam had been washed out by flood. Abundant curved stalagmites were typical, hanging above the lakes. At about 700 m from the entrance, the “Hangar” hall is developed (35 by 20 by 16 m). Behind this point, the passage width decreases from 10 - 15 m to only 6 m. One kilometre from the entrance, several domes (up to 40 by 20 by 15 m in size) created by ceiling break down occur. Around that place, there are three shafts connecting the cave with the surface; all about 40 m high. These can be used as an alternative entrance to the cave, but there is a trouble with anchoring, as the salt is fragile and corrosive and the unstable sediments on the surface under the cave give only small possibility for making stabilization points for the ropes.

Upstream to the shafts the draught dies out and the character of the passage changes: The arched spaces modelled by breakdown that occur below the shafts turns into a very wide spaces with almost flat ceiling without any traces of collapsing. The first harder crawlway “Bend” is about 150 m long. The passage becomes larger and larger further on. On the right side, there is a permanent shower of brine called “Waterfall”. This 10 m high vertical chimney was climbed in 2006 using an aluminium ladder. 170 m long minor meandering passage was mapped in the upper level. The passage continues, but the spaces are very narrow and frequent fractures and fallen blocks from the ceiling indicate increased danger of collapsing.

On the left side of the main corridor, there is an older level, so called “Snow Passage”. The main corridor reaches the width of 40 m and height up to 6 m here (“Namakdan Highway”). Suddenly the large corridor turns right and quickly decreases clearing to only half a metre. The most challenging – more than 500 m long – “Azadi´s Crawlway” starts here. Fortunately the crawlway was bypassed in 2004 by a shortcut “Motashakkeram” we dug through an older +6 m level, so now one could safely reach the upstream parts of the cave in case that some flooding occurs. Either way one gets to “Megadomes”. These are two extensive, but relatively low halls – together they occupy an area of 200 by 100 by 2-8 m. They are situated at a confluence of streams from two main ponors of this cave. Further upstream one can take a fossil corridor named "Old Passage" or another crawlway "Active Passage" with an active channel, wide but of a very low clearing. The latter was connected to Big Ponor Cave this year.

The Big Ponor entrance is situated in a deep ravine with extremely unstable sides. An ephemeral stream drains a flat plateau of eastern Namakdan disappears in a huge portal (35 by 15 m) below some 100 metres of a hanging wall. After a large entrance hall (ca 50 by 50 by 15 m) there are several low passages in different directions. They became inaccessibly low after several tens of meters due to a coarse gravel fill. In January 2006 we dug through the fill and found several hundred metres of new passages and finally also the way to Cave of Tøí Naháèù. The new spaces are generally very low, filled by sand and coarse gravel to cobbles. Especially after a major precipitation event, the whole Big Ponor part might be very dangerous. First, because of collapsing of the ceiling and second, there is a place marked “Sandy Sump” on the map, that becomes filled by water and sediments during flooding (it was impassable in 2004). There are a number of other shorter passages going in various directions wedging out because of a sedimentary filling.


The Upper Entrance Cave (length 650 m.) is probably connected to the 3N Cave though the connection was not confirmed yet. Cave entrance is developed in a blind end of a ravine, similar but smaller to that leading in the Big Ponor Cave. The cave begins with a labyrinth of very low passages that have joint flat roof of rock-salt, bottom and sides are built by coarse cobbles, gravel and sand. Some 60 m from the entrance, a large corridor starts. Unfortunately, this larger corridor mapped during previous expeditions was not accessible in January 2006 because of a plug of sediments. The distance from the end of mapped passages to the 3N Cave is only about 130 m. As the water can apparently pass through, there is a chance that the inner parts of the Upper Entrance Cave will open again in future.

Oaj Mountain Climbing Club's report

We explore this cave for the first time in Mar 2008 .
15 members of our club could search only about 1500 m. of cave because of their short of time .
But we will back again this year to complete this wonderful undegroun expedition .

Passing through many long tunnels which their height is less than 0.5 m. or through salty waters with wounded body are some of hardnesses for exploring this cave .
But after seeing the cave's pics , you will be agree with me that its beauties are more than its hardnesses .
Exploring the main route of cave (6580 m.) needs about 30 hours and you should carry night sleeping wears and enough drinking waters .

I should thank from my freind Omid Akrami (one of team members) for his nice pics from this cave .

External Links

expedition's report from czeck radio
speleogenesis.info
Oaj Mountain Climbing Club

Images

View (3N) Namakdan Cave Image Gallery - 34 Images