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192 PROCESS AND FORM




              Table 8.2—Cont’d
              Form                          Comment

              Bare limestone forms (concentrated surface runoff)
              Microfissures                  Small fissures, up to several centimetres long but no more than 1 cm deep,
                                             that follow small joints
              Splitkarren                   Solution fissures, centimetres to a few metres long and centimetres deep,
                                             that follow joints, stylolites, or veins. Taper with depth unless occupied by
                                             channel flow. May be transitional to pits, karren shafts, or grikes
              Grikes (Kluftkarren)          Major solution fissures following joints or fault lines. The largest forms
                                             include bogaz, corridors, and streets
              Clints (Flackkarren)          Tabular blocks between grikes
              Solution spikes (Spitzkarren)  Sharp projections between grikes

              Partly covered forms
              Solution pits                 Round-bottomed or tapered forms. Occur under soil and on bare rock
              Solution pans                 Dish-shaped depressions formed on flat or nearly flat limestone, with sides
                                             that may overhang and carry solution flutes. The bottom of the pans may
                                             have a cover of organic remains, silt, clay, or rock debris
              Undercut solution runnels (Hohlkarren)  Similar to runnels but become larger with depth resulting from damp
                                             conditions near the base associated with humus or soil accumulations
              Solution notches (Korrosionkehlen)  Inward-curved recesses etched by soil abutting rock
              Covered forms
              Rounded solution runnels (Rundkarren)  Runnels formed under an ‘acidulated’ soil or sediment cover that smooths
                                             out the features
              Cutters                       An American term for soil-covered grikes that are widened at the top and
                                             taper with depth. Intervening clints are called subsoil pinnacles
              Solution pipes, shafts, or wells  Cylindrical or conical holes developed along joint planes that connect to
                                             proto-caves or small caves. Shaft-like forms weathered below a deep and
                                             periodically saturated soil cover contain small caverns and are known as
                                             ‘bone yard’ forms. These are popularly used in ornamental rockeries
              Polygenetic forms – assemblages of karren
              Karren fields (Karrenfeld)     Exposed tracts of karren that may cover up to several square kilometres
              Limestone pavement            A type of karren field characterized by regular clints and grikes. They are
                                             called stepped pavements (Schichttreppenkarst) when benched
              Pinnacle karst and stone forest  Topography with pinnacles, sometimes exposed by soil erosion, formed on
                                             karst rocks. Pinnacles may stand up to 45 m tall and 20 m wide at the
                                             base
              Ruiniform karst               Karst with wide grikes and degrading clints exposed by soil erosion.
                                             Transitional to tors
              Corridor karst or labyrinth karst or  Large-scale clint-and-grike terrains with grikes several metres or more wide
               giant grikeland               and up to 1 km long
              Coastal karren                A distinctive solutional topography on limestone or dolomite found around
                                             coasts and lakes

              Source: After discussion in Jennings (1971, 1985) and Ford and Williams (1989, 376–7)
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