It seems to me that in addition to "surveyed length of passage" we
could use some other metrics. How do you measure "cave area"?
How much area does Mammoth Cave occupy? How many entrances? What's the
total volume? What's the longest path between entrances? What's the
longest trunk passage?
How much area does Powell's Cave occupy? 3 entrances if you count the
mine shaft and the downstream siphon. How long is the longest "trunk"
passage (i.e. the stream passage)? Ditto for Honey Creek.
How much area does Inner Space occupy? At one time it had only 1
entrance if you count the first 24" core hole, zero if you don't.
How much area does Fort Stanton occupy? Only 1 entrance and 1
resurgence. The Snowy River trunk passage is "5 miles long" making the
straight line distance between extremities around 3.8 miles.
How do you count long lava tube passages with multiple entrances?
Ditto for gypsum caves. In Jester Cave you can travel between two
portals around a mile apart.
After you all answer these questions we could create an appropriate
algorithm and re-rank all our favorite caves.
- Pete
On Jan 11, 2012, at 9:06 AM, Mark Minton wrote:
I agree that it doesn't matter what configuration cave
passages make. Stacked levels, parallel passages, tight groups of
passages, etc. are all still passages as long as they are in solid
rock. But how can you rationally count multiple routes through
breakdown as separate passage? There is basically one (maybe more)
larger space filled with rocks that one can go around and through in
different ways. But it's still just one passage. One wouldn't count
different routes through a thicket of formations as different
passages. What if there were a single passage with a large block of
breakdown mostly filling it. Say there is just enough room to squeeze
around either side and over the top. Who would count that as three
separate routes? Breakdown-filled passages or rooms are the same
thing on a larger scale. Of course sometimes the breakdown is so
extensive that it is not readily apparent where the walls really are,
in which case it gets tough to define what is a passage and what
isn't. The map usually reveals the basic outline, though.
Mark
At 08:52 AM 1/11/2012, Jim Kennedy wrote:
Punkin Cave is currently has just over 4 kilometers of surveyed
passage. There is almost 5 kilometers of total survey, but as Carl
rightfully points out, some of that is room perimeter shots and some
is splay shots, which do not count towards the total passage
length. All of the current 4km is traversable passage length. We
are careful not to confuse survey length with passage length. Note
that I explicitly say passage length. If you consider passage
length the length of the cave, then this is a meaningful number. It
doesn't really matter if the passage is one long straight line or
all bunched up into a big ball. If you have to cover the same
distance (crawling, walking, climbing, swimming, or whatever) to get
"see" all the available passage in the cave, what does it matter
whether that passage is horizontal, vertical, spiral, air or water
filled, or whether it is a straight line or a jumbled mess? And I
also disagree about not counting passages through breakdown. If you
can get through it, it is a passage, no matter if the walls are
solutional or the walls are tectonic. If we pursue that bias, then
suddenly entire caves such as Enchanted Rock and Mount Emory
suddenly are no longer caves!
Jim Kennedy
Punkin Cave Survey Coordinator
From: Carl Kunath [mailto:carl.kun...@suddenlink.net]
Sent: Wednesday, January 11, 2012 1:08 AM
To: TexasCavers
Subject: [Texascavers] How long is Punkin Cave?
How Long is Punkin Cave?
Punkin Cave serves as a wonderful way to get new cavers and
potential surveyors underground to useful purpose. Kudos to those
who keep plugging away at this project.
It has been announced that Punkin Cave, presently at 13,400+ feet,
is now the 10th longest cave in Texas and the 369th longest cave in
the United Sates, having surpassed such caves as Kartchner Caverns
(Arizona), Adams' Cave, and Caverns of Sonora in Texas.
It seems to me that this is a classic example of confusing the
length of survey lines applied to a cave with its actual "length."
When caves are reasonably linear and not too wide, a survey line
down the down the "center" of the passage with occasional shots to
the side to establish wall location will give a good idea of the
length so long as the side shots are not counted as length.
The reality is that not all caves are that easy to assign a
meaningful length number.
Consider Grutas de Bustamante. It's a huge, booming passage, often
several hundred feet wide but with little in the way of side
passages. There has been a lot of survey activity in there over the
years, most notably the heroic effort by Jan and Orion Knox. the
passage is really too wide to survey by just moving down the
middle. Some survey efforts have gone down one wall, and then
returned along the other. Did the combined length of those survey
lines double the length of the cave?
Consider Endless Cave (New Mexico). It's a complicated maze cave
with only a few traditional linear passages. I couldn't tell you
how long it is because the traditional notion of "length" is
nonsense in this situation. When the survey was completed, it was
noted that more than 10,000 feet of survey lines were required.
Another way to look at that is to state that by traveling a non-
repetitious 10,000-foot circuit, one might reasonably claim that
they had "seen" the cave.
The situation at Punkin Cave is even more extreme. Here, there is
an irregular but somewhat pyramidal void mostly filled with cemented
breakdown. To date, nowhere is it possible to be more than a few
hundred feet from the surface datum. To laboriously survey
multiple, interconnecting routes through such a three-dimensional
maze and then add the survey lines together for a "length" is absurd.
The point farthest from the entrance datum is ~350 feet. If the
"length" of the entrance drop is subtracted, the figure is even
less. The entire known cave is contained within a space 460 feet
long, 200 feet wide, and 210 feet high.
How "long" is Punkin Cave? You decide, but please don't ask me to
believe its presently known length is more than 2.5 miles!
===Carl Kunath
Please reply to mmin...@caver.net
Permanent email address is mmin...@illinoisalumni.org
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