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Karst Science and The Geological Society of America

GSA TODAY | JANUARY 2015 Cory W. BlackEagle, Dept. of Earth and Environmental Science, geomorphological, and meteorological components that interact
University of Kentucky with and upon one another both at Earth’s surface and in the
GSA’S NEW KARST DIVISION subsurface (Fig. 2). Connections between all components can be
dynamic and operate on very short to very long time scales. Such
Thanks to the efforts of a large number of people and two terranes can be active and contemporary, inactive, and/or
years of very dedicated and determined efforts, we are very completely decoupled from current conditions. Features
pleased to announce that GSA Council approved the creation of commonly associated with karst terrane include caves, sinkholes,
the GSA Karst Division! springs, disappearing streams, and surface areas lacking any
Division officers for our inaugural year are as follows: surface drainage or naturally occurring water bodies.
• Chair and JTPC representative: Cory BlackEagle, Dept. of
WHERE IS KARST?
Earth and Environmental Science, University of Kentucky;
• 1st Vice-Chair: Bonnie Blackwell, Chemistry Dept., Williams In the U.S., rocks with the potential to be karstic occur in every
one of the 50 states, and ~18% of their area is underlain by soluble
College; rocks either having karst or the potential for its development (Weary
• 2nd Vice-Chair: Jason Polk, Dept. of Geography and Geology, and Doctor, 2014). Portions of major U.S. cities are underlain by
karst (e.g., St. Louis, Missouri; Nashville, Tennessee; Birmingham,
Western Kentucky University; Alabama; Austin, Texas; and Louisville, Kentucky). According to
• Secretary: Penny Boston, Dept. of Earth and Environmental Veni et al. (2001), karst terrane underlies ~25% of the global land
surface. Ford and Williams (1989) estimated “that 25% of the global
Science, New Mexico Tech; population is supplied largely or entirely by karst waters” (p. 6)
• Treasurer: Ben Tobin, National Park Service; and (Fig. 3), and ~1.5 billion people live in karstic terrane.
• Webmaster and Social Media Coordinator: Pat Kambesis,
UNDERSTANDING KARST DEVELOPMENT AND FUNCTION
Dept. of Geography and Geology, Western Kentucky University. IS CRITICAL
WHAT IS KARST?
Karst terrane serves as a fragile foundation for both urban and
Karst is a terrane1 comprised of distinctive landforms (Fig. 1) rural populations. However, for most people, karst systems are
and hydrology in which the host rock is highly soluble in the pres- unknown or ignored, falling into the mindset of “out of sight, out
ence of naturally occurring acids. Karst terrane is an open system of mind.” Nonetheless, among karst scientists, the catch-phrase of
that contains geological, hydrological, biological, geochemical, “what goes down must come up” has long been used to summa-
rize how water flows through karst aquifers. Perhaps even more
Figure 1. Broadway, or Main Cave, inside Mammoth Cave along the historic importantly, though, this simple phrase serves as a strong warning
tour route. Photo taken from the top of the Corkscrew looking toward the about how easily contaminants may appear in and pollute karst
Rotunda. Image courtesy National Park Service. wells and springs.

The world’s largest springs and most productive groundwater
supplies are karstic, yet water resources in karst areas are the most
easily polluted. Karst hydrology and hydrogeology are complex
and still confound the best efforts at modeling. Water quantity
and quality can change rapidly and dramatically. Storage in karst
aquifers can vary from nonexistent to time frames of thousands of
years, and its character and mechanisms are still largely unknown.
Contaminants can be transmitted miles from their source and
re-emerge without dilution in locations completely unanticipated.
Flooding in karst terrane can be extensive and dramatic.

Karst terranes are areas of exploitable and critical natural
resources, such as water, limestone for building stone and aggre-
gate, minerals, oil, and natural gas. Important oil and gas produc-
tion throughout the world occurs in fields that formed in porous

1The term “terrane” as used here is typically defined as an area or region with a distinctive stratigraphy, structure, and geological history. A specific terrane can be
distinguished from neighboring terranes by its different history, either in its formation or in its subsequent deformation and/or metamorphism. The term “terrain”
refers to the elevation, slope, and orientation of land features. It can be argued, therefore, that the karstic terrain (landscape) is a subset and consequence of the features
and processes (stratigraphy, structure, and geologic history) that define the karst terrane in which it occurs. To describe an area of karst as “terrain” excludes the sub-
surface suite of geologic factors that led to its creation and critically interact with it.

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