Page 210 - Fundamentals of Geomorphology

KARST LANDSCAPES 193

of 1 mm or more within a few decades. The main Solution flutes
bare forms resulting from surface wetting are solution (Rillenkarren )
Planar belt of no
ripples, solution flutes (Rillenkarren), solution bevels channelled erosion
(Ausgleichsflächen), solution runnels (Rinnenkarren),
and decantation runnels and flutings (Table 8.2; Hortonian-type
Figure 8.6; Plates 8.1 and 8.2). runnels
Bare forms resulting from concentrated runoff are
microfissures, splitkarren, grikes, clints, and solution
spikes. Microfissures are solutional features following
small joints. Splitkarren are larger solution channels that
run along larger lines of weakness – joints, stylolites, and
veins. Grikes (Kluftkarren), which are called solution
slots in America, follow joints and cleavage planes, so
may be straight, deep, and long, often occurring in net-
works (Plate 8.3). Grikes are the leading karren feature in Decantation runnels
most karren assemblages. Large openings may develop at
joint intersections, some several metres deep and called
karst wells, which are related to solution pipes and pot- 1
holes. The intervening tabular blocks between grikes 2
are called clints (Flackkarren) (Plate 8.3). Grikes in
upright bedding planes are enlarged in the same ways 3
as joints in flat bedding planes and are called bedding
grikes (Schichtfugenkarren). However, residual blocks
left between them commonly break into pinnacles or
solution spikes (Spitzkarren) and beehives decorated
1. Source not in direct contact with surface
by solution flutes. In horizontal strata, the near-surface 2. Source in direct contact with surface
bedding planes are likely to be opened up by seepage. 3. Source no longer present
This process may free the intervening clints and lead to
their breaking up to form shillow (a term from northern Diffuse Decantation
England), which is roughly equivalent to the German sheet flutings
Trümmerkarren and Scherbenkarst. All these forms are flow
small. Grikes average about 5 cm across and up to several
metres deep, clints may be up to several metres across,
and solution spikes up to several metres long. Large-scale
grikes, variously termed bogaz, corridors, and streets, are
found in some areas and follow major joints and faults.
Bogaz are up to 4 m wide, 5 m deep, and tens of metres
long. Karst corridors and streets are even larger and take
the form of gorges. Figure 8.6 Solution flutes (Rillenkarren), decantation
runnels, and decantation flutings.
Source: After Ford and Williams (1989, 383)
Covered and partly covered forms
Partly covered forms develop in areas with a patchy
soil, sediment, litter, or moss cover. Solution pits are
round-bottomed or tapered forms, usually less than 1 m