Karst & It’s Importance

In my observations it has become apparent that there’s a possible epidemic of karst eroding nationwide. It has been going on in the state I live in currently for years. In fact, Lake Huron has sinkholes near Alpena, Michigan that NOAA has been researching for a few years now. There are also sinkholes In the ground in various locations around & in Alpena.
I love geology and am rather fascinated by karst. I have some big chunks of limestone karst washed up on the shore of the majestic Great Lake. I ‘d like to share some insight as to what is karst and why karst is so important.

What Exactly is Karst?
Karst is a landscape formed from the dissolution of soluble rocks including limestone, dolomite and gypsum. It is characterized by sinkholes, caves, and underground drainage systems (Fig. 1).


Nearly all surface karst features are formed by internal drainage, subsidence, and collapse triggered by the development of underlying caves (Palmer, 1991). Rainwater becomes acidic as it comes in contact with carbon dioxide in the atmosphere and the soil. As it drains into fractures in the rock, the water begins to dissolve away the rock creating a network of passages. Over time, water flowing through the network continues to erode and enlarge the passages; this allows the plumbing system to transport increasingly larger amounts of water (Gunn, 2004). This process of dissolution leads to the development of the caves, sinkholes, springs, and sinking streams typical of a karst landscape.

Why is Karst Important?
Dissolution associated with karst development in central Texas limestone has created a complex underground water flow network that includes caves large enough for humans to access. Rainwater travels through the network, controlled by the Balcones fault system, until it reaches the water table (Ferrill et al., 2004). The karstified limestone acts as an aquifer where water can be stored and later extracted by humans.

Two million people in central Texas get their drinking water from the karst aquifer known as the Edwards Aquifer (Sharp and Banner, 1997). This resource is especially important for central Texas as the region becomes more urbanized. With a higher density of people, central Texas will face higher demand and increased pollution. Just like rainwater, pollutants can easily pass through the karstified limestone. Another difficulty is that streams and surface runoff entering the aquifer via sinkholes and caves bypass the natural filtration produced by seeping through soil and bedrock. This direct recharge quickly replenishes the water supply; however, it also leaves the aquifer particularly vulnerable to contamination (Drew and Hötzl, 1999).

Drew, D. and Hötzl, H, 1999, Karst Hydrogeology and Human Activities: Impacts, Consequences and Implications. Brookfield, VT: A.A. Balkema Publishers, 332p.
Ferrill, D.A., Sims, D.W., Waiting, D.J., Morris, A.P., Franklin, N.M., and Schultz, A.L., 2004, Structural framework of the Edwards Aquifer recharge zone in south-central Texas. Geological Society of America Bulletin, v. 116(3-4), p. 407-418.
Gunn, J., 2004, Encyclopedia of Caves and Karst Science. New York: Fitzroy Dearborn, 902p.
Palmer, A.N., 1991, Origin and morphology of limestone caves, Geological Society of America Bulletin, v. 103, p 1-21.
Sharp, J.M., Banner, J.L., 1997, The Edwards Aquifer: a resource in conflict, GSA Today, v. 7 (8), p. 1-9.

FAIR USE NOTICE: This site contains copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available in an effort to advance understanding of environmental, political, human rights, economic, democracy, scientific, and social justice issues, etc. We believe this constitutes a ‘fair use’ of any such copyrighted material as provided for in section 107 of the US Copyright Law. In accordance with Title 17 U.S.C. Section 107, the material on this site is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes. For more information go to: http://www.law.cornell.edu/uscode/17/107.shtml.

If you wish to use copyrighted material from this site for purposes of your own that go beyond ‘fair use’, you must obtain permission from the copyright owner.


One thought on “Karst & It’s Importance

  1. Pingback: The Karst Mountains: A Must See in Everyone's Lifetime | viptravelers

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s