CAVE SURVEYING

1
Karst Investigation Methods George
Dasher Groundwater-UIC Program West
Virginia Department of Environmental Protection
2
What is Karst?

• Karst is the solution of certain rocks
• such as limestone, dolomite, gypsum, or salt
• by surface water and groundwater

3
Karst is characterized by

• Thin soils and bedrock exposures
• Few or no surface streams
• Sinkholes
• Caves
• Sinking streams
• Dry streams
• Large springs
• Fast groundwater flows
• Little groundwater filtration

Limestone Outcrop in Jefferson County
4
Dry Stream
Sinkhole Plateau with No Surface Drainage
Cave Entrance
Karst
Big Spring
Sinking Stream
Roadside Karst Indicator
5
West Virginia Karst

• Four different karst-forming limestones
• Avis Limestone
• Greenbrier Group limestones
• Helderberg and Tonoloway limestones
• Ordovician and Cambrian limestones
• Three different kinds of karst areas
• Appalachian Plateau
• Mountainside
• Lower Shenandoah Valley

Greg Springer, 2000
6
Traditional Karst Investigation Methods

• Literature search
• Talk to farmers and landowners
• Walk the area
• Look for caves, springs, and sinking streams
• Complete dye traces
• Measure stream flows
• Survey the significant caves

Caver On Rope Exiting a Cave
7
Literature Search

• Public Libraries
• State Geological Surveys
• West Virginia Geological Survey
• Public information
• State Speleological Surveys
• West Virginia Speleological Survey
• Proprietary information
• National Speleological Society
• NSS News
• Journal of Cave and Karst Studies
• Speleo Digests
• Cave club newsletters
• Old cave maps

WVGS Geological Map
WVASS Publication
8
Talk to Farmers and Landowners

• Can be a great source of information
• Will often know a lot about the local geology
• Will know a lot about recent geological events
• Floods
• Cave collapses or opening of entrances
• Water well information
• Such as depth to bedrock

9
Area Inventory

• Walk the study area and look for
• Geology
• Sinkholes
• Caves
• Water sinks
• Springs
• Losing streams
• Gaining streams

A Small Streamside Cave Entrance
10
Describe and Locate the Karst Features

• Describe
• Geology
• Size
• Water flows
• Biology
• Locate
• Topo map
• GPS receiver
• Or both

Checking out a Cave Entrance
11
Dye Tracing

• Is used to determine karst groundwater flow
  routes
• Is an extremely important investigative technique
• Dye is placed in stream sinks and caves
• Traps are placed in caves, springs, and surface
  streams

Dye Being Placed in a Cave Entrance
12
Green Fluorosceine
Direct Yellow
All of these dyes are harmless!
Red Rhodamine
Fluorosceine dye reappearing
13
Dye Traps

• The traps are about 1 by 4 inches in size
• Construction
• Screen-door screen held in place with office
  staples
• Held in the water by wire or nylon fishing line
• Attached to weights, rocks, posts, or vegetation
• Charcoal trap (on right)
• Used for fluorescein and rhodamine dyes
• Cotton trap (on left)
• Used for Direct Yellow and Optical Brighter dyes

14
Dye Tracing 101

• Place traps
• At locations where the dye may appear
• Place at least two traps at all critical
  locations
• In surface streams above and below possible
  underwater springs
• At locations above where you think the dye may
  appear
• You want some clean traps in your results, as
  this tests your field method
• In dry streams where the water flow may turn on
  while you are away from the study area
• Always place and collect your traps first
• This way you will not accidentally contaminate
  your traps with your dye

15
Dye Tracing 201

• Multiple dyes can be used in the same basin
• Both kinds of traps can be used at all locations
• Both traps can be used to catch at least two dyes
• This cuts down on work time
• Trap placement and collection takes the most time
• Single dyes can be used within the same basin
• You must move upstream each time you use the same
  dye
• Or you must move to a clean sub-basin within
  the overall basin
• Important checks!
• Trap the basin beforehand to insure that there
  are no dyes in it
• Storm pulses are required to clean the basin of
  dyes every so often

16
Dye Traces in the Droop Mountain Area
17
Dye Tracing

• Can also be used to determine dye travel times
• Automatic samplers are placed at the downstream
  locations

• The dye placement time is recorded
• The dye collection time is recorded
• A graph is then constructed

18
Dye Tracing Problems

• Each dye trace only gives a single snap shot in
  time
• This snap shot may change as the groundwater
  levels vary!
• Dye tracing does not work well from groundwater
  monitoring wells
• The dye simply stays in the well
• False positives
• Cow urine
• Laundry products
• Dye and/or traps are sometimes lost
• The dye trace must then be repeated

Spectrofluorometer Used to analyze for the
various dyes
19
Measure Stream Flows

• This is an important tool!
• Should be done at both high and low flows
• This shows which springs and streams are
  perennial and which are seasonal
• The bad news
• It is a snap shot in time!
• Karst springs and streams are always changing in
  volume

Measuring a Stream Flow
20
Locating Underwater Springs

• Some springs are located underwater in streams
  and pools
• These can be found by
• Measuring the increases in the volume of the
  surface stream above and below the suspected
  spring
• Measuring the conductivity and/or temperature of
  the surface water above and below the spring
• Simply wading up or down the surface stream on a
  hot day and feeling for cold spring water

Measuring a Spring Flow in High Water
21
Survey the Significant Caves
Cave survey crews
This can be critical to understanding a karst
area!
22
Instrument Person
A Suunto Compass and Clinometer
Book Person
Tape Person
23

• Cave maps
• Can be very informative!
• Can show
• Geology
• Passage trends
• Passage size
• Passage depth
• Water flows
• Old water flows

24
Cave Radio
Can be used to find a surface position above the
radios location in the cave
25
Non-Traditional Karst Investigation Methods

• Electrical Resistivity
• Requires several dozen electrodes placed in the
  ground and an electrical source
• Is good for locating buried metal objects
• Soil moisture can be a big factor

Resistivity Survey

• Electrical Magnetic
• Requires a long tube that is held horizontally
  and carried about the site
• Cars, fences, etc. can produce interference
• Can produce very fast results

26
Non-Traditional Methods.

• Seismic Refraction
• Requires sensors called geophones
• Requires a sound or vibration source
• Typically a sledge hammer is pounded on a heavy
  piece of metal
• Cannot locate underground features smaller than
  the spacing of the sensors
• Ground-Penetrating Radar
• Requires an electromagentic pulse that measures
  subsurface reflections
• Is dependent on the presence of water
• Clay, caused by the weathering of limestone, can
  limit the useable depth

27
Non-Traditional Methods

• Mirco Gravity
• Requires a weight of known density and mass
• Depends on elevation, the location of the Earth,
  Sun, and Moon, as well as the density of the
  materials below each station
• The receiver must be moved from station to station

Micro Gravity Survey

• Borehole Analysis and Geophysical Logging
• Requires an open borehole and downhole tools
• Can be relatively expensive, but can be very
  effective
• Should be used to confirm the results of other
  surveys

28
Conclusion Just Remember!! If youre having
troubles locating karst Then go back to the
basics
29
And follow the signs
30
Thats all there is, Folks!
Saltpeter Vat, Greenbrier County
The Sinks of Gandy
Mastodon Humerus, Monroe County
Eastern Pipistrelle Bat