Backdoor Cave
25.404700,92.589700
Description
A sinkhole, which was interpreted as a relatively large swalet hole [sic!] with 10 m high cliffs around and was characterised by a climb down 3 m over large boulders (handline useful) gives access to a stream sink with perennial stream leading down to wet canals. Partially draining the upper reaches of Lymmoh canyon [Phud Lymoh]. Hoped for connection to Krem Khung but the cave went off [sic! qua; turned off] in the opposite direction. Probably due to shale barrier (Arbenz, T 2013.04.01 Mss: Mark Tringham 16th Feb 2013 Back Door Not Cave 5.2.2013). EVALUATION 2014: Stream sink with perennial stream leading down to wet canals. Partially draining the upper reaches of Lymmoh canyon (Arbenz, T 2014.01.04 Mss: 2014.01.02 Back Door Not Cave 5.2.2013). ETYMOLOGY: No autochthonous, indigenous or locally known name has been identified for what ousiders referred to as Back Door Not Cave Arbenz, T (2013.04.01 Mss: Mark Tringham 16th Feb 2013 Back Door Not Cave 5.2.2013); Arbenz, T (2013.10.11 Mss Mark Tringham 16th Feb 2013 Back Door Not Cave 5.2.2013); Arbenz, T (2014.01.04 Mss: Back Door Not Cave 5.2.2013) Backdoor-Not Cave Arbenz, T (2013.04.01 Mss Backdoor-Not Cave.doc); Arbenz, T (2013.12.31 BackdoorPlan.pdf) Khung Back Door Arbenz, T (2013.04.01 Mss: Mark Tringham 16th Feb 2013 Back Door Not Cave 5.2.2013); Arbenz, T (2013.10.11 Mss: Mark Tringham 16th Feb 2013 Back Door Not Cave 5.2.2013) Khung Back Door Not anonymous Arbenz, T (2013.08.07 Mss: Meghalaya Expedition 2013 Diary) [Krem Pira?] Arbenz, T 2014.01.04 Mss: 2014.01.02 Back Door Not Cave 5.2.2013). SITUATION: Between the Pala spur and the Moo Knor spur, west (down) from the Pala-Saipung Road in the upper area of Lymmoh canyon (Arbenz, T 2013.04.01 Mss; Arbenz, T 2014.01.04 Mss). POSITION 2013.02.05: Location for a point 15m on bearing 200 deg from the entrance was 25 deg 24 min 16.8 sec N. 92 deg 35 min 22.9 sec E, elev 847 m (anonymous in Diary 5th February 2013 Tuesday) equalling (unspecified precision error) 25°24'16.8”: E092°35'22.9”: 847 m asl (unidentified geodetic datum possibly WGS84). POSITION 2013.04.01: Only 3.45 km in a direct line too far east near (allegedly ±15 m) N25°24'16.8”: E092°37'26.0” (Arbenz, T 2013.04.01 Mss -Mark Tringham 16th Feb 2013- Back Door Not Cave 5.2.2013). POSITION 2013.10.11: Near (allegedly ±15 m) N25°24'16.8”: E092°35'22.9” (Arbenz, T 2013.10.11 Mss -Mark Tringham 16th Feb 2013- Back Door Not Cave 5.2.2013). APPROACH: From Moo Knor proceed towards Pala to milestone 4/5 (N25°23’46.5”: E92°35’27.2”) and continue for another 300 m. Near N25°23’52.5/E92°35’22.0’’ a track leads down the valley towards Lymmoh canyon. About 20 mins walk takes you to a first flat farming area with terraced paddy fields. The entrance is a sink at the top of the fields (Arbenz, T 2013.04.01 Mss; Arbenz, T 2014.01.04 Mss: 2014.01.02 Back Door Not Cave 5.2.2013). CAVE DESCRIPTION 2013: The descending passage heads generally NE. There is a drop after 100 m that requires a3 m ladder. After the “Crab Cake Walk” and the first fault chamber the cave becomes low and wet with stooping-sized canals. Two fault chambers follow. After that a dry cave passage is reached. It has a left hand branch leading upward to a drafting rift with a choke. The right hand branch leads along wet rifts to a sump (Arbenz, T 2013.04.01 Mss). Keyword: Diving spot. CAVE DESCRIPTION 2013b: The expedition geologist confidently predicted a large pitch descending into the backend of Krem Khung … In practice the cave remained stubbornly horizontal; the only bolt being placed was for a short ladder on a 4 m drop. However the caving was pleasant, mostly walking following joint controlled passage. After a section of stooping wet passage a flat out bedding crawl (4 m) was encountered requiring the optimistically worn SRT kit to be removed. This popped out of the wall a new 3 m high passage. This was followed downstream for 100 m (ish) to a wet section (30 m ish) where a route has to be pickd out between the roof pendants. A total soaking to the shoulders is unavoidable. A dry standing chamber is gained with the passage continuing. … The connection to the crawl is easy to miss however a few meters further up the passage a bypass is found back to the original passage. Continuing upstream, unfortunately the new passage soon choked (anonymous Arbenz, T 2013.08.07 Mss: Meghalaya Expedition 2013 Diary). CAVE DESCRIPTION 2014: A large swalet hole with 10 m high cliffs around. Climb down 3 m over large boulders (handline useful). The descending passage is large and heads generally NE. There is a drop after 100 m that requires a short (3 m) ladder. After the big “Crab Cake Walk” and the first big fault chamber the cave becomes low and wet with stooping-sized canals. Two large fault chambers follow. After that the final (dry) passage is reached. It has a left hand branch leading upward to a tight draughting rift with that is obstructed by a boulder choke. The right hand branch leds to wet small rifts which finally sump (Arbenz, T 2014.01.04 Mss: 2014.01.02 Back Door Not Cave 5.2.2013). PROSPECTS 2013.02.07: Mark E Tringham, Bushan Poshe and Urs -Waelchli- Wälchli noticed that Time ran out but it was seen that the cave continues for at least another 50 m beyond (anonymous Arbenz, T 2013.08.07 Mss: Meghalaya Expedition 2013 Diary: 7th February). TACKLE: 10 m hand line at entrance is useful. 4 m ladder required about 100 m into the cave (Arbenz, T 2013.04.01 Mss). CAVE LIFE: Crabs and crayfish common. Interesting fungus (Arbenz, T 2013.04.01 Mss; Arbenz, T 2014.01.04 Mss).
Documents
Bibliography 06/01/2018Histoire
EXPLORATION HISTORY: 2013.02.05, trip 1: M.Tringham, B.Poshe, D.Cooke locate the cave and start survey (Arbenz, T 2013.04.01 Mss: Mark Tringham 16th Feb 2013 Back Door Not Cave 5.2.2013). 5th February 2013 (Tuesday) … Mark, Cookie, Bhushan … headed for the point indicated from underground surveying of the left hand branch at present cave end of Krem Khung. After continuing for another 200 m they found a significant size swallet just upvalley from a group of rice paddies. Location for a point 15 m on bearing 200 deg from the entrance was 25 deg 24 min 16.8 sec N. 92 deg 35 min 22.9 sec E, elev 847 m. The cave commenced with a 3 m rope climb and then a descending passage mostly of good size in rifts for about 75 m. At this point a further climb down of about 4 m into a chamber was reached requiring another rope. In the absence of further tackle the team headed out taking a few photos on the way. The forward plan was to survey and continue with more tackle. The team also explored upstrea on the surface and found the upper part of the limestone with moderate dipping bedding planes but no further entrances. After rendez-vous with Team 2 a further surface exploration in a NE direction was made to ensure nothing was missed. It was noted that the two teams found the top limestone surface several tens of metres different elevation showing that a likely fault occurs between the two valleys explored (anonymous Arbenz, T 2013.08.07 Mss: Meghalaya Expedition 2013 Diary). 2013.02.06, trip 2: 6th Feb 2013: M.Tringham, B.Poshe, D.Cooke, U Waelchli continue the survey along main passage (Arbenz, T 2013.04.01 Mss: Mark Tringham 16th Feb 2013 Back Door Not Cave 5.2.2013). 6th February 2013 (Tuesday) … Krem Khung Back Door Not … Team 1 (Pushing) -- Cookie, Urs … [pushed pushing till] The survey team was met. A second survey set was passed to team 1 who proceeded to start surveying the smaller passage joining at station 1/10. Stations 10/0 to 10/4 were surveyed before time ran out. Cokie confirmed the passage looped backed to main passage as predicted (anonymous Arbenz, T 2013.08.07 Mss: Meghalaya Expedition 2013 Diary). 2013.02.06, trip 3: On the same 6th February 2013 (Tuesday) … Krem Khung Back Door Not … Team 2 (Surveying) – Mark, Bhushan [Mark E Tringham, Bushan Poshe] started the survey at the entrance and followed the main drag until time ran out. Stations 1/0 to 1/38 (anonymous Arbenz, T 2013.08.07 Mss: Meghalaya Expedition 2013 Diary). 2013.02.07, trip 4: Krem Khung Back Door Not … Mark E Tringham, Bushan Poshe and Urs Waelchli [sic! qua: Wälchli] … had a second trip in and continued surveying and exploring with a total for the cave now at 560 m. First they surveyed all the side passages noted the previous day and these included one loop and two inlet tributaries. Then secondly they pushed on down-stream from the end of a Crabs Cake Walk into a moderately large fault chamber. An awkward canal section was surveyed followed by yet another fault chamber. Tim ran out but it was seen that the cave continues for at least another 50 m beyond (anonymous Arbenz, T 2013.08.07 Mss: Meghalaya Expedition 2013 Diary 7th February). 13th Feb 2013: M.Tringham, B.Poshe, N.Tringham surveyed to conclusion [abandonment of the survey progress] (Arbenz, T 2013.04.01 Mss) of the act of surveying. 2013.02.13, trip 5, Wednesday: Krem Khung Back Door Not Mark E Tringham, Nicholas Tringham & Bushan Poshe had a 3rd trip in with the expectation of completing the cave. On the inward journey an hour or so was spent on photography with some acceptable results. The exploration and surveying was extended with about 80 m added to the previous total beyond, in a downstream direction. The [penetration of this] streamway ended with small low canal rift passages gradually descending to water level, while [the penetration of] an ascending upper drafting rift passage ended with a narrow choked crack (anonymous Arbenz, T 2013.08.07 Mss: Meghalaya Expedition 2013 Diary: 13th Feruary, Wednesday).2013.12.31: Thomas Arbenz constructed BackdoorPlan.pdf, a digital cave plan, after survey data and sketches which had been provided ten months earlier by Mark E Tringham.
Cavités proche
| Distance (km) | Nom | Longueur (m) | Profondeur (m) |
|---|---|---|---|
| 0.5 | FANNY CAVE | ||
| 0.5 | GRANNY CAVE | ||
| 0.8 | LYMOH POTS CAVE | ||
| 0.8 | LYMOH CANYON CAVE | ||
| 0.9 | SPURT CAVE | ||
| 1.0 | CHILLI CAVE, Lymoh, 2nd | ||
| 1.0 | CHILLI CAVE, Lymoh, 1st | ||
| 1.1 | LYMOH, upper (Krem) | ||
| 1.4 | UMTHYMMAI, Shnong Ryngkoh (Pung) |