Supplemental Trip Report
Cave Inventory Report

Permit: Unknown
Leader: Bob Lerch
date: 6 Dec 2003
manager: Bob Lerch
Assessment: Convention Hall
participant1: Bob Lerch
participant2: Dan Austin
participant3: Bill Gee

TimeIn: 11:00am Sat
TimeOut: 2:30am Sun
Damage: No
Date: Thursday December 11, 2003
Time: 06:43 PM


Mapping, geology and biology survey around Convention Hall.


Survey team was Bill Gee, Bob Lerch and Dan Austin. Lerch did book, Gee did lead tape and Austin did instruments. Gee did bio and geo survey and Austin did some profile and cross section sketches.

Uncertain survey mark, probably near UL2-16: 6 cave fish observed in the stream. Two of them were quite large, near two inches. The fish were fairly active, probably because we disturbed them while crossing the stream. We did not look for isopods.

UL2-55: Flying bat. Tentative ID by Dan Austin as a Grey bat.
Clay/sand mix
Loose rocks

UL2-56: Clay/sand mix
Loose rocks

UL2-56A1: Clay/sand mix covering “floor” (actually a shelf above main passage)
A few short soda straws on the ceiling, 3 inches and shorter.
Loose rocks.

UL2-57: Flying bat
Clay/sand mix

UL2-58: Two flying bats
Breakdown leading into tight passage
Clay/sand mix
Loose rocks

UL2-59: Two flying bats
Clay/sand mix on floor and covering walls
Thin layer of flowstone on walls, mostly covered with clay

Note – At 3:45 pm a bat landed near UL2-59. Dan Austin positively identified it as a Grey bat.

UL2-60: Breakdown and loose rocks on floor
Clay/sand mix on floor and covering walls to about 10 feet above the lowest point on the floor.
Water dripping from ceiling

General notes on Convention Hall dome room:
There is breakdown and loose rock over the entire floor. The material ranges from sand/clay mix to chair-size rocks.
Several patches of manganese on the walls, ID by Dan Austin. I think some of them are chert outcrops
The main waterfall comes from around what appears to be a manganese deposit.
Many holes eroded in the wall, from straw-size to a foot in diameter. It’s like Swiss cheese.
There are some bat droppings on the walls. Not many. Perhaps 8 or 10 per square foot.
Around the waterfall the floor is covered in chert rocks, most are football size and smaller.
Flowstone drapery on the wall 8 to 10 feet up.
There are several drains at the base of the dome.
I checked several small puddles ranging up to about a foot across. No signs of isopods or any other life.
There are some mud flows along the walls.

There are several obvious drains out of the base of the dome. Only one is large enough for a human to enter. The rest all have running water in them, but not nearly what might be expected given the volume of the waterfall. It almost appears as if a stream flows around the base of the dome just out of site and reach of humans.

I crawled down into a drain located to the left of the waterfall as you enter the room. There was just about enough room for me to crouch and turn around. The floor of this drain is about 2 feet below the floor of the main dome room. A small stream flowed through here. 14-16 inches wide, less than an inch deep. No signs of life. There were no rocks larger than sand, so I did not look for isopods. Everything was covered in mud. I got pretty well slimed getting out.

I climbed into a side passage about 4 feet off the floor on the left side as you enter the room. It only goes 30 or 40 feet before pinching off. I saw a beetle in this passage. Unknown species. It did not look like the ptomophagus picture in Elliott’s book. It was about 1/4 inch long. The head was very small in relation to the abdomen. Abdomen was dark brown.

UL2-61: Breakdown
Small pool about 4 inches diameter
Flying bat
Mud-covered walls

UL2-61A1: Big breakdown
Clay/sand mix on a slope
Some water drips

UL2-61A2: This station is on the overlook ridge near the top of Convention Hall dome.
Breakdown up to refrigerator size
Clay/sand mix

UL2-61A3: Very large breakdown, up to car size. Covers entire floor.
Small white flowstone on west wall, down low. There is an associated pool about 1 foot by 2 feet with a white calcite rimstone on each side.
Clay/sand mix covering most surfaces including walls almost to the ceiling.
A few short soda straws on northwest side, under 4 inches long.
Lots of drips near south wall. A few pools, no formations. No signs of life in the pools.

UL2-67: Flying bat
Clay/sand mix covering surfaces and walls to near ceiling

UL2-68: Breakdown
Clay/sand mix covering most surfaces
Very loose rock on a steep slope
Flat ceiling.

UL2-69: Small breakdown
Very loose rock on floor
Clay/sand mix under a ledge
Dripping water