Southeastern Section - 64th Annual Meeting (19–20 March 2015)

Paper No. 6
Presentation Time: 4:40 PM


ISPHORDING, Wayne C., School of Continuing Studies, Tulane University (Biloxi Campus), 2600 Beach Blvd., Suite 18, Biloxi, MS 39531,

Geoscientists have long accepted that a "true" karst terrane refers to "a solution-controlled topography characteristic of regions underlain by carbonate rock." Other locations that possess similar geomorphic features NOT developed on carbonate rock have been termed "pseudokarst." While various arguments for separating the two certainly have scientific merit, these arguments simply cannot be defended in a court of law. Those who have experience in testifying under direct- and cross-examination know well the hazard of introducing the term "pseudo" as part of their testimony. Such terms are prized by opposing attorneys and are invariably used in the summation stage of the trial to impugn or discredit the testimony of expert witnesses who have made use of them

A definition of karst as "topography formed by dissolution of the bedrock and which is characterized by closed depressions, caves, underground drainage, etc.," creates no problems for the expert witness. By not restricting this definition to limestone, dolomite or gypsum, however, permits strong arguments to be raised that allow this definition to be applied where similar "karst-like" features are developed on such diverse rocks as unconsolidated sandy-clays, quartzites, peridotites, basalts, granites, and a number of other rock types. Two examples are provided where the expert witness was able to defend his client’s claim for damage coverage under the "sinkhole" clause in his homeowner’s insurance policy (in spite of the fact that both residences were not constructed on carbonate rocks). The argument that "if it walks like a duck and quacks like a duck, it is a duck" was successfully argued by the plaintiff’s attorneys in both cases. Expert witnesses for the defense (i.e., the insurance companies) were unable to provide sufficient arguments acceptable by the juries that excluded the insurance carriers from liability. Hence, it is now clearly apparent that only a policy that specifically restricts solution and/or settlement damage to homes constructed on carbonate rocks (or gypsum) can be successfully defended. Policies not clearly identifying the rock type allow a plaintiff’s expert to show that the only true difference between solution phenomena on carbonate rocks, versus those on other rock types (e.g., granite) is the rate at which dissolution takes place.