In 2006, the term “pseudokarst” celebrated its one hundredth anniversary, as it (strictly the term “pseudokarstification”) was first used by W. Knebel in 1906 (Bella 1995).

The term “pseudokarst” is commonly used in some countries of Central Europe (for example in Slovakia, Czech Republic), but quite a number of scientists (e.g. in the neighbouring Poland) do not accept it, arguing that it is not precisely defined and that the process of dissolution (thus karstification) plays a crucial role also in the weathering of the rocks, which were previously considered to be not-karstified, as sandstones and granites. This first argument is true - many people use the term “pseudokarst forms”, although they adopt different definitions of “pseudokarst”. And great number of geologists, geographers and speleologists have tried to define this term in various ways or have simply rejected this term (see e.g. Kunsky 1957; Otvos 1976; Panoš1978; Bella 1995; Self, Mullan 1997). The authors differ in usage of the terms “pseudokarst” and “karst” even when they describe the same processes (compare: Čilek 1998 and Self, Mullan 2005).

Commenting on this second argument – regarding the dissolution of “not-karstified rocks” – it should be emphasized, that process of karstification consists not only in dissolution, but also the transport of rock material as a solution plays a significant role in it, so enabling efficient rock destruction deep underground. This second phenomenon is responsible for the development of vast underground hydrological systems typical for karst. In the case of sandstones or granites, a majority of the weathered material is transported in a detrital form and therefore, the term “karst” can be used only for processes occurring in microscale; whereas for meso- and macroscale the terms “pseudokarst” or “clastokarst” (this second one was introduced and defined by V. Panoš, 1978) still seem to be valid.

For this reason the term “pseudokarst”, although not enough clear, is very convenient for a general determination of forms and phenomena similar to karst, but originated due to (partly) non-karst processes, especially caves, sinkholes, swallow holes and other mesoforms. And the motto “pseudokarst” has been adopted by people interested in these specific, often unique forms on the International Symposia on Pseudokarst for a quarter of a century! The year 2007 is the 25th anniversary of the international symposia on pseudokarst.
Anyway, the discussion on the principles, definitions and terminology may be very profitable for our better understanding of processes and forms, which are unique, specific or even amazing and are very often described as “pseudokarst”. So, all of you are invited to this discussion.

Jan Urban

Bella P. 1995 - Kras and pseudokras – fundamental terminological problems (English sum.). In: Gaal L. (ed.). Proc. of Intern. Working Meeting "Preserving of Pseudokarst Caves". Rimavska Sobota-Salgótarján, SAŽP Banska Bystrica: 68-76.
Čilek V. 1998 – The physical and chemical processesof sandstone pseudokarst genesis (English sum.). In: Čilek V., Kopecký J. (eds), Das Sandsteinphanomen – Klima, Leben und Georelief. Libr. Czech Spel. Soc. v. 32: 134-153.
Kunský J. 1957 – Typy pseudokrasových tvarů v Československu. Českoslov. Kras 10, 3: 108-125.
Otvos E. G. 1976 – “Pseudokarst” and “pseudokarst terrains”, problems of terminology. Gdeol. Soc. Amer. Bull. 87, 7: 1021-1027.
Panoš V. 1978 – Krasové typy podle hledisk geologických. Acta Univ. Palackine Olom., Facult. Rer. Nat. 58, Geogr.-Geol. 17: 83-101.
Self C., Mullan G. 1997 – Karst and pseudokarst. In: Chabert C., Courbon P., Atlas des cavités no calcaires do monde. Un. Intern. Spéléol.: 14-15.
Self C., Mullan G. 2005 – Rapid karst development in an English quartzitic sandstone. Acta Carsol. 34, 2: 415-424.