6.12 Microsculpturing of Solutional Rocky Landforms · 6.12 Microsculpturing of Solutional Rocky Landforms J Lundberg, ... they do develop on less-soluble rocks in ... The various

6.12 Microsculpturing of Solutional Rocky LandformsJ Lundberg, Carleton University, Ottawa, ON, Canada

r 2013 Elsevier Inc. All rights reserved.

6.12.1 Introduction 1226.12.1.1 Significance 1226.12.1.2 Basic Controls on Formation 1226.12.2 Major Karren Forms 1226.12.2.1 Solution Pits/Basins 1226.12.2.2 Rainpits 1236.12.2.3 Solution Pans (Kamenitzas) 1236.12.2.4 Solution Bevels (Ausgleichsflachen) 1246.12.2.5 Trittkarren (Heelprint Karren), Trichterkarren (Funnel Karren), and Lame Dentates (Sharpened Toothed

Edges) 1246.12.2.6 Microrills (Rillensteine) 1256.12.2.7 Rillenkarren (Solution Flutes) 1256.12.2.8 Rinnenkarren 1266.12.2.9 Decantation Runnels and Flutings, and Wandkarren (Wall Karren) 1276.12.2.10 Rundkarren 1286.12.2.11 Splitkarren, Grikes (Kluftkarren), Cutters, and Clints (Flachkarren) 1286.12.2.12 Subcutaneous Karren (Bodenkarren) 1306.12.2.13 Karren Wells 1306.12.2.14 Cavernous Karren/Subsoil Pits (Kavernosen Karren) 1316.12.2.15 Solution Notches (Korrosionskehlen) and Subcutaneous Half-Bells 1316.12.2.16 Solution Pipes (Geologische Orgeln) 1326.12.2.17 Spitzkarren 1326.12.2.18 Pinnacles 1326.12.3 Karren Assemblages 1326.12.4 Classification 1356.12.4.1 Classification Based on Physical and Chemical Properties of Solvent and Solute 1356.12.4.2 Important Karren Regions 1356.12.5 The Future 137References 137

GlossaryAggressivity This is the potential of a fluid to be corrosive

to the material under discussion. Aggressive water is not yet

saturated with a chemical (such as limestone) and can thus

dissolve more of that chemical.

Condensation corrosion This is the weathering/

dissolution of rock surfaces caused where vapor (commonly

water) condenses directly onto rock surfaces, causing

corrosion if the condensate is aggressive.

Eogenetic rock Young rocks that have not been buried by

later sediments, largely uncompacted, commonly poorly

cemented, and of high primary porosity.

Epikarst This is the network of intersecting fissures and

cavities from surface weathering on the upper surface of a

karst landscape that delivers surface water to the

underground drainage system, typically a few centimeters to

tens of meters deep.

Hortonian channel A channel that forms where rainfall

exceeds infiltration capacity and overland flow is focused

into a channel.

Hydraulic gradient This is the gradient of the water table,

a higher water table giving a steeper hydraulic gradient,

especially toward the edges of scarps.

Osage Rivers/streams that fail to meander within a

meandering valley.

Underfit River that appears to be too small for its present

valley.

Treatise on Geomorphology, Volume 6 http://dx.doi.org/10.1016/B978-0-12-374739-6.00129-9 121

Lundberg, J., 2013. Microsculpturing of solutional rocky landforms. In:

Shroder, J. (Editor in Chief), Frumkin, A. (Ed.), Treatise on

Geomorphology. Academic Press, San Diego, CA, vol. 6, Karst

Geomorphology, pp. 121–138.

Abstract

Karren (small-scale dissolutional features) have a great variety of forms and are known by a huge suite of terms. Bare rock

forms are sharper and more gravitomorphic than subcutaneous forms, where rock-fracture control may dominate. Fourcontrols operate: (1) physical properties of the solvent (fluid flow, surface tension, and percolation); (2) chemical properties

of the solvent (unmodified rainwater, enhanced aggressivity, and reduced aggressivity); (3) chemical properties of the solute

(rock solubility); and (4) physical properties of the solute (fractures and rock texture). Large expanses of bare rock karren

are called karren fields, the more famous including China’s ‘Stone Forest’, Madagascar’s ‘Tsingy’, and Mulu’s ‘Pinnacles’.

6.12.1 Introduction

Microsculpturing refers to the small-scale, usually o2-m scale,

dissolutional features of rock surfaces that are generally

known by the German term ‘karren’ (less often by the

French term ‘lapies’). Most are the result of dissolution alone

(sometimes mediated by biological activity) but direct bio-

logical action may be most important for some features.

Although most characteristic of the soluble carbonates

and evaporites, they do develop on less-soluble rocks in

suitable conditions. There are no easily definable limits: kar-

ren grade into landforms as the scale increases and grade into

surface texture at the microscale. Large area of sculpted bare

rock, commonly with many and complex types, are termed

‘karrenfields’.

This section covers karren features of freshwater surface

environments (microsculpturing of marine and cave en-

vironments is covered elsewhere in this volume). The section

is also limited to those features presumed to be largely solu-

tional in origin – microsculpted features from other processes,

such as alveoli/tafoni, are not included here. This section

is arranged with a brief presentation of the basic controls,

followed by a description of the major forms, and karren

assemblages. This is all put together in the final section which

is the classification.

6.12.1.1 Significance

Because the term ‘karren’ can be applied to any small-scale

dissolutional feature, they are the most widespread karst

landform and in the field it is often the karren that are

the first-noticed indicators of the presence of soluble rocks.

Karrenfields are important hydrologically because they are the

access routes through which groundwaters are recharged. They

preserve valuable information about conditions in the recent

past (e.g., newly revealed subsoil karren may indicate soil

erosion rates), in the more distant past (e.g., karren type may

indicate a different climatic regime – most commonly tropical

forms in a now-temperate region), and in the very distant past

(e.g., paleo-karren indicate subaerial exposure and thus paleo-

sea level). In some areas, the extraordinary, dramatic, bizarre

landscapes of karren act as a significant tourist attraction

(e.g., the Stone Forest of Southern China, and the Pinnacles of

Mulu, Sarawak).

6.12.1.2 Basic Controls on Formation

Microsculptural features are related to very small scale, very

local conditions of hydrology, physics, chemistry, and

biology (see Bogli, 1980, 1981; Jennings, 1985; Gines, 2004;

Trudgill, 1985; White, 1988; Ford and Williams, 1989). The

environmental setting can be very important, generally in re-

lation to the presence of a vegetation cover or a soil cover, as is

the type of material being eroded. Some are exposed only to

subaerial erosion (better known because visible), and some

only to subcutaneous erosion (under a cover of soil/sedi-

ments/vegetation – being invisible, these are commonly less

well known). However, in the field, most features have had a

more complex history with some periods of burial and some

of exposure.

The various factors that govern the development and form

of karren in a complex web of interactions include:

• rock factors – lithological variations (the small scale:

chemistry, crystallography, depositional fabric, etc.) and

structural variations (the larger scale: sedimentary structure,

bed thickness, orientation, dip, joint frequency and orien-

tation, etc.) – this may include inheritance of morphology

from previous geomorphological regimes such as glaciation;

• hydrological factors – how water impinges on rock

(e.g., raindrops vs. sheet flow vs. channeled flow vs. wet

overburden) and chemical properties (e.g., biogenic-CO2

enhancement, stored, and decanted water; water from

snow vs. rainfall vs. sea spray vs. dew, etc.);

• biological factors – both direct (e.g., boring) and indirect

(e.g., biochemical action); and

• environmental factors – climate, aspect, situation (tem-

perature averages and ranges, precipitation averages and

ranges, intensity, temporal distribution, physical form –

e.g., snow, dew – wind direction and intensity, etc.) – this

may also include inheritance from previous climates.

6.12.2 Major Karren Forms

This section describes the most common karren forms, with

the more frequently used names (see Sweeting, 1972; Jakucs,

1977; White, 1988; Ford and Williams, 1989; Fornos and

Gines, 1996; Gines et al., 2009). Nomenclature remains

problematic – because Bogli was so influential in early studies

of karren, many of the German terms have been adopted

worldwide (Bogli, 1951, 1960, 1980, 1981) – however, because

of differences in language and real differences in forms ob-

served in different regions, we still find many local terms. Even

within English, differences commonly exist between US terms

and others. In the account below, some have been grouped if

they cannot logically be separated into distinct forms.

6.12.2.1 Solution Pits/Basins

Of varying dimensions from cm to dm scale, roughly circular

in plan, round bottomed in section, pits may stand alone or

122 Microsculpturing of Solutional Rocky Landforms

develop in clusters on bare rock or under an acidic soil cover

or under dripping vegetation. Many are clearly associated with

organic activity, but many are not. Pits are commonly reported

from arid areas and are likely related to bacterial corrosion.

Sometimes pits align along joints or along glacial striations.

Pits commonly are part of a hierarchy of forms, the surfaces

inside many of the larger karren features being etched with

small pits – especially on the edges of water surfaces where

cyanobacteria colonize. At the extreme end of complexity of

solution, pitting is the karren of eogenetic rocks such as those

of young carbonate islands. This is usually a pseudo-random,

almost three-dimensional assemblage of pits of many sizes, in

hierarchies of small pits making up bigger pits, the whole

extremely rough to the touch, popularly known as ‘moonrock’

(Figure 1).

A unique form of lacustrine pitting develops at the edge of

some freshwater lakes in the region of oscillating water levels.

The more exposed is the simplest, with shallow round

pits (Figure 2). The pits are of variable size but rarely bigger

than 5 cm in diameter. A little further offshore, the pits

become more complex, penetrating the rock surface by some

15–20 cm but branching, curving, and coiling in vermiform

manner, each ‘worm’ being about the size of a human finger.

Another extraordinary lacustrine form has been described

from Ireland (Gines et al., 2009), developed on the undersides

of bedding planes where rising waters, saturated with respect

to calcite, trap pockets of air under rock ledges. Condensation

corrosion within these isolated pockets then carves perfectly

circular cigar-shaped tubes upwards into the base of the bed.

These tubes (‘Rohrenkarren’) are generally up to B5 cm in

diameter and up to B30-cm deep.

6.12.2.2 Rainpits

These are distinct from general solution pits in that they only

form at bare rock crests, and they never occur alone. They

completely pack the surface in a mini-polygonal network, the

inter-pit knife-edged cusps commonly meeting in little sharp

spikes. Rainpits give way downslope to rillenkarren. They form

from the direct action of raindrop impact and, thus, are gen-

etically associated with rillenkarren (below). In addition, they

have the same parabolic cross section as rillenkarren and the

same order of magnitude at 1–4 cm diameter.

6.12.2.3 Solution Pans (Kamenitzas)

Kamenitzas are circular in plan but flat bottomed (Figure 3),

commonly with a sharp change of slope from the horizontal

floor to the riser, or even an undercut, and shallow compared

to their diameter. They develop only on bare rock, on flat to

gently sloping surfaces, where water does not readily drain

away and organic material can easily be trapped. The flat floor

is usually lined with a thin film of organic or other material,

Figure 2 Lacustrine pits in the Amabel dolostones at the water’sedge, Bruce Peninsula, Canada (the case is 30-cm long). Pits indeeper water are deeper and more vermiform.

Figure 1 A typical multipitted rock surface from Bonaire,Netherlands Antilles, with pits of various sizes forming a generallyrough surface (notebook is B15-cm long).

Microsculpturing of Solutional Rocky Landforms 123

which apparently armors the floor and directs corrosion to the

walls. When the walls are intact, the pan will fill with water

during rainfall. However, many have an overflow channel,

which is a type of shallow decantation runnel (below). Although

not controlled by rock features, if a kamenitza encounters a joint

it may become elongate, tear-shaped, or it may drain. Kame-

nitzas can be up to several meters deep and wide (e.g., some are

42-m deep in Chillagoe, Australia – but in this complicated

setting these may have become flat-floored pans only as a

modification of inherited subcutaneous forms), usually some

10–100 cm in diameter and a few cm to a few dm in depth.

Coalescence of adjacent pans produces pans of complex form.

Development seems to be variable. In many cases, the first

stage is of coalescing pits that are each developing downwards

and laterally. In other cases, the kamenitza may develop by

lateral corrosion of an existing depression (perhaps inherited

from covered conditions). Once it has started, the flat floor

appears to continue development essentially as a dissolutional

bevel (below) created by back migration of the walls.

6.12.2.4 Solution Bevels (Ausgleichsflachen)

A solution bevel is a plane of relatively smooth bare rock

that has no relationship to lithological control, where sheet

erosion is presumed to occur but no channeled erosion

(Figure 4). Bevels are distinct from other smooth flat faces,

such as glacially planed surfaces, because they are the product

of dissolution. They can form as remnant from backcutting of

walls (they are a micro-scale version of the arid region pedi-

ments that are presumed to develop by lateral planation) such

as the walls of kamenitzas, or trittkarren (below). Bevels also

develop where the water film is too thick to allow direct im-

pact of raindrops onto the rock surface and not thick enough

to allow separation into channeled flow (see example of

rillenkarren below). The bevels created from lateral planation

are usually close to horizontal, but those associated with ril-

lenkarren can slope up to about 701 in the downstream

direction. Sometimes gently sloping surfaces develop a series

of bevels en echelon, the ranks of wide, low steps providing

easy footing up the slope. They do not have any characteristic

size, but, because sheet flow is apparently necessary for their

continuation, the size must be limited by hydrodynamic

conditions to maintain the intact sheet.

A subclass of solution bevel appears to be the landscape-

scale ‘corrosion terraces’ or ‘mega-ausgleichsflachen’ that are

common in high-altitude glacio-karst regions. These have

the characteristics of a normal solution bevel with a backwall

of at least 10 cm, but are many meters wide. It becomes more

problematic to envisage an unbroken sheet flow of these di-

mensions, but easy to envisage if sheet flow is maintained

between rock and snow. Similar huge solution bevels are

reported from the Madre de Dios karst of Patagonia where

strong winds prevent flow from separating into channels

(Gines et al., 2009).

6.12.2.5 Trittkarren (Heelprint Karren), Trichterkarren(Funnel Karren), and Lame Dentates (SharpenedToothed Edges)

These features are associated with solution bevels, have no

association with rock structural features, and appear to be

most common in regions with winter snow cover. Trittkarren

Figure 4 A series of solution bevels associated with parallel retreatof trittkarren, on marbles of Glomdal, Norway (notebook is B20-cmlong). These can be seen emerging from their winter cover of snow.The forms appear to completely disregard both the joints (vertical)and the metamorphic texture.

Figure 3 Looking straight down into kamenitzas from Chillagoe,Australia (black rectangles on ruler¼ 10 cm). The interpan surfacedisplays the generally pitted–rilled surface that is ubiquitous on barekarst rock. The walls of the pans are themselves made of pits andare undercut in pans that drain enough that they no longer fill to thebrim and dissolution is then concentrated at the base of the wall.


(Figure 5) form on relatively gently sloping bare-rock surfaces

where a semi-circular, nearly vertical, backwall retreats into the

slope creating the heelprint-shaped bevel. The change of slope

from the floor to the backwall can be sharp and rounded

as well. Typical dimensions are 10–40 cm in diameter and

3–20-cm deep at the backwall. They may be isolated but more

commonly occur in groups. Some with wide headwalls,

elongate plan but small openings like a bottleneck, appear

to be transitional to kamenitzas that have drained. Where

adjacent trittkarren coalesce the shared riser remains only as a

rib protruding from the headwall (as in Figure 4). On the

margins of grikes trittkarren may form a series of steps.

Trittkarren form under shallow sheets of turbulent flowing

water. They may be initiated from flow detachment and re-

attachment over a small preexisting step (as in formation of

scallops). They are most commonly reported in association

with winter snow cover and have been attributed to micro-

snowdrift formation – however, the occurrence of suites of

wide, low trittkarren on the west coast of the rarely snowy

Burren, Ireland (untested impressions suggest they are limited

to the wind-swept Atlantic edge) complicates the issue. De-

velopment varies with slope: on low slopes both the tread and

the backwall develop in tandem, the backwall reaching

1–2 cm in height and the tread a few dm in length (as in

Figure 5). For steeper slopes (10–301), the riser will be several

cm and the tread 10–20 cm. The backwall develops faster than

the floor. On the steepest slopes, the riser will be several dm

whereas the tread will be 1–2-cm wide (Figure 6). These look

as if a large beaver has been gnawing on the rock.

Trichterkarren are deep armchair to funnel-shaped forms

on steeper slopes, usually on edges draining into grikes. The

backwall is the dominant feature and the floor area minor.

Although they also generally have a circular to semi-circular

plan, here the form is not so geometrically clean as the tritt-

karren, the floor is not commonly flat, and the walls are more

funnel-shaped than vertical. They are likely developed from a

normal trittkarren where the floor has been overdeepened into

a channel.

A form that appears to be related, in that it is also associ-

ated with melting snow and sheet flow, is the Lame Dentate or

sharpened, toothed edge. These develop only on steep slopes

(4501) where snow melt dissolves most of the surface of the

rock face in a relatively smooth sheet, but leaving emergent a

suite of parallel ridges, elongate downslope (that look very

much like tiny versions of crag and tail glacial flutes with the

sharp-edged crag upslope and the tail streaming out down-

slope, or suites of tiny elongate rock drumlins/flutes). This

form suggests that sheet flow is constrained between the snow

and the rock face.

6.12.2.6 Microrills (Rillensteine)

Rillensteine (Figure 7) are packed suites of tiny dissolution

channels B1–2-mm wide and round bottomed in section,

sharp edged, and up to B10 cm in length. In plan view, they

range from parallel (on steeper slopes), to anastomosing, to

tightly sinuous (on more gentle slopes). They are essentially

gravitomorphic forms, largely unaffected by rock structure.

They develop in many different climatic regimes – especially

the more arid ones – but are expressed only on very fine-

grained to aphanitic rock and where downslope flow of

very thin films of water is modified by capillary tension from

evaporation and, possibly, wind. Detailed studies show that

the more complex examples are not true linear forms but are

rather alignments of microdepressions (Gines et al., 2009).

6.12.2.7 Rillenkarren (Solution Flutes)

Rillenkarren are suites of parallel channels that form at the

crest of a bare-rock slope and develop downslope from the

crest (Figure 8), but they become extinguished downslope. In

Figure 6 Trittkarren on steep slope, marble, Norway (Bruntoncompass for scale). These do not have a clear flat tread surface thatis distinct from the riser.

Figure 5 Small, simple trittkarren on low slope, marble, Norway(case is B30-cm long).


this they are significantly different from normal fluvial

drainage channels that develop toward the base of a slope and

extend upslope by headward erosion (i.e., normal Hortonian

channels). Where rillenkarren develop to either side of a

ridged crest, their back-to-back intersection describes a her-

ringbone pattern along the crest. On a more rounded crest,

they splay out in a more complex pattern. Rillenkarren do not

exist singly – they are always packed together with knife-edged

separators and, in places, mini-pinnacled separators. In cross

section, they are parabolic (Figure 9). In long section, given

sufficient uninterrupted rock face, they will peter out, yielding

to a smooth, nonchanneled ausgleichsflache.

Rillenkarren are gravity controlled and best developed on

moderate slopes. On quasi-horizontal slopes the form that

develops from direct raindrop impact is the rain pit. On steep

slopes, only the thinnest of flows remains attached. Detach-

ment of flow interrupts the fluting process and cockling

(sharp-edged rib-like ripples) develops transverse to the flow,

breaking up the flute form, giving a rough box-like texture.

Rillenkarren size varies with rock type, smaller on gypsum

than limestone. Dimensions on limestone are 1.770.27-cm

wide, 0.4470.18-cm deep, and 1977-cm long. Depth and

length vary, but width is remarkably constant world wide –

any rill that is outside of the range 1.3–2.1 cm is probably not

simple rillenkarren.

Many simulations have been done with gypsum blocks and

artificial rain to elucidate the mode of development (e.g., Glew

and Ford, 1980). The formation of rillenkarren is linked to the

impact of direct raindrops on the rock surface where the film

of runoff is still shallow enough that the kinetically energetic

drops cut through it. The bevel forms where runoff depth is

greater than the critical depth that can be penetrated by rain

drops. Many of the morphological features support this model

of development: rillenkarren depth and length relate directly

with temperature and length increases with slope.

6.12.2.8 Rinnenkarren

Rinnenkarren (the closest English equivalent, ‘solution run-

nels’, seems to be used widely for a variety of channels, those

formed on bare rock or under soil) are gravity-controlled

Hortonian channels that develop on bare rock as the sheet of

runoff becomes deep enough to separate into channels, the

equivalent of normal fluvial gullies on nonkarst hillsides. The

angle with the surface is sharp, and the cross section is usually

a rounded ‘U’. The essential feature is that they increase in

depth downslope as discharge increases. Rinnenkarren tend to

merge downslope in a dendritic network, but on steep slopes

they remain quasi-parallel (Figure 10). Typical examples are a

few decimeters wide and deep, and tens of meters long. There

is no limit to width and length but, in most cases, they are

Figure 7 Meandering rillensteine on limestone, Vancouver Island,Canada.

Figure 8 Looking down on rillenkarren developed on both sides of acrest (Brunton compass for scale), Surprise Valley, British Columbia,Canada. The rills give way downslope to the smooth ausgleichsflache,the solution bevel.


limited by the available area of unmodified rock surface.

Most end in grikes or drain into rundkarren (below). They can

extend upslope by headward erosion.

Although by definition rinnenkarren form on bare rock, in

the field many are complex, with histories of changing vege-

tation cover (e.g., as grazing pressure increases or decreases).

Larger rinnenkarren may have scallops (transverse erosional

ripples) in the channel where flow separates and reattaches.

The sides of some may become modified by rillenkarren.

Some rinnenkarren may develop channels within channels

(smaller channel incised into base of bigger channel), or long

sections with basins and steps. Any karren form can get

blocked by clumps of vegetation or build up of organic matter.

In this case, local dissolution is enhanced and the form may

become undercut. In the case of an undercut channel this is

called hohlkarren and is a common feature of rinnenkarren

or emergent rundkarren. Rinnenkarren with a square cross

section are of complex origin, for example, the flutes that

form where rillenkarren amalgamate (seen on Figure 9 above,

marked with a white X).

On gentle slopes any runnel may meander. From the lit-

erature, it is not clear that meanderkarren should be given

a separate category. It appears that rinnenkarren (bare rock

forms), decantation runnels (half-covered forms), or rund-

karren (covered forms) may meander given suitable slope

(B7–141 is optimum) and flow conditions. To be called

meanderkarren, a runnel should have sinuosity and an

asymmetric cross section, with a talweg that crosses from side

to side (i.e., normal features of a fluvial meandering channel).

Some become deeply entrenched, leaving hanging terraces,

narrow necks, and isolated rock spurs. If the discharge changes

then meanderkarren can show similar patterns of misfit

as normal rivers (e.g., manifestly underfit and Osage-type

underfit).

6.12.2.9 Decantation Runnels and Flutings, andWandkarren (Wall Karren)

The descriptive terms ‘runnel’ and ‘flute’ refer to any gutter-like

drainage channel. The runnels and flutes described above are

formed of simple rainwater. If the solvent has been modified

by storage such that it gains aggressivity, then the dissolution

potential is maximal on emergence, on first contact with the

rock, and decreases with flow. Thus, the decantation form gets

shallower downslope. The source of modified solute may be as

small as a leaf or a clump of organic matter/vegetation, or it

may be as big as a soil cover or a bedding plane. If the solvent

emerges as a point source, then a decantation runnel forms

(Figure 11). If it emerges as a sheet, then a parallel suite of

decantation flutings forms (Figure 12). There is no limit on

the size of decantation forms but most are o20-cm wide and

Figure 10 Exceptionally long rinnenkarren on the 451 slopes ofHutton Roof Crags, Lancashire, UK.

Figure 9 The sharp-edged parabolic cross section of rillenkarren,here developed on salt, Cardona, Spain. The white X marks the flat-bottomed larger flute (from amalgamation of several rills) that is acomplex rinnenkarren.


extinguish in o10 m. On gentler slopes, the channels may

meander.

A type of runnel that is not clearly of distinct genesis is the

Wandkarren or Wall karren. These develop where water flows

down vertical slopes. They are parallel to each other, and have

a semi-circular cross section. There is no limitation on size, but

typically they are some cm to dm in width and less deep than

wide. They are generally best developed on the edge of a scarp,

or the sides of a karren well. Because they cannot acquire any

more solvent, they peter out downslope as the solvent gets

exhausted. In this respect, they are typical decantation forms.

It can easily be seen from Figure 12 that the removal of the

soil reservoir would leave typical wall karren.

6.12.2.10 Rundkarren

A channel that forms under a cover of thick vegetation or soil

(and exposed through soil erosion) will generally show

smooth-rounded surfaces everywhere. The channel gets deeper

downslope (as with all normal Hortonian channels). There is

no inherent limit on size – they simply get larger with time

and more acid conditions – but they are usually B2–50-cm

wide and up to 50-cm deep. As with rinnenkarren, they will

tend to stay parallel on steeper slopes (Figure 13), or converge

into a dendritic or centripetal pattern (Figure 14). Rundkarren

are in some cases smooth on emergence from a soil cover,

gradually getting more lichen covered and sharpened by

subaerial dissolution. Because rundkarren form under the soil,

and thus flow does not separate or cavitate, they can develop

on vertical walls (as in Figure 20 below).

6.12.2.11 Splitkarren, Grikes (Kluftkarren), Cutters, andClints (Flachkarren)

Fractures in bedrock (usually tectonic joints and usually in

parallel series that intersect to form a geometric grid pattern,

but sometimes veins or stylolites), acting as lines of preferred

dissolution, become deepened and widened over time. The

resultant network of ‘canyons’ is a fundamental part of

the epikarst system that diffusely feeds recharge waters into the

karst. The most commonly used term for the canyon is ‘grike’,

and for the remnant flat-topped intercanyon plateau, ‘clint’.

Lithological control is exerted largely by susceptibility of the

rock to regular fracture patterns – for example, neither chalks

nor eogenetic rocks of young carbonate islands typically

show grike and clint forms – and by rock response to stress

Figure 12 Suite of decantation flutings developed beneath a shelf ofsoil in Glomdal, Norway, showing the characteristic shallowingdownslope form.

Figure 11 A gently meandering decantation runnel emergent from apoint source; in this case, a kamenitza, Gait Barrows, Lancashire, UK(the case is B30-cm long).

Figure 13 Parallel rundkarren in marble of northern Norway,emergent from the soil, and now being sharpened by subaerialdissolution.


fields – for example, intersection angles in plan view are

typically 601, 901, and 1201, joints are usually perpendicular

to bedding planes, joint density is inversely proportional to

bed thickness, and not all joints propagate through many

beds. Grike (and clint) development is, thus, under rock

control as expressed over time.

The first stage of opening of the fracture is the splitkarren

(Figure 15). These vary from short, shallow (anything from

1 mm up to B10 cm in depth) V-shaped indentations that

follow the guiding fracture, to linear slots up to B10 cm in

width and several dm in length (many like knife-cuts into

fabric).

Grikes may develop directly on bare rock (and seem to

have developed from enlargement and coalescence of split-

karren), or they may be initiated under a thin soil cover and

emerge as that soil is lost down the opening joint. The best-

expressed networks of grikes are those developed on now-

exposed glacially scoured bedding planes (Figure 16). The

guiding fractures are not always linear (Figure 17).

One of the significant controls on grike size is the strength

and direction of the hydraulic gradient. The largest grikes

develop in the area of greatest hydraulic gradient and in

line with the gradient. The presence of drainage channels

then locally modifies hydraulic conditions so that secondary

grikes develop along joints roughly normal to the principal

grikes. In north-western Yorkshire, England, grikes may be

15–60-cm wide at the surface, and commonly 0.5–3-m deep,

a reflection of the time available for dissolutional modifi-

cation since glacial retreat. Grikes can develop downwards

from dissolution on the surface, sideways from headward

erosion and amalgamation of splitkarren, or upwards from

subsurface dissolution. Colonization by vegetation accelerates

development.

Where grike development is not limited by recent glacial

scour, they can become impressively large. The upper limit of

size is presumably governed by rock stability, those in com-

petent rocks reaching several meters in width and tens of

meters in depth, as in the Giant Grikelands of Chillagoe and

Kimberley, Australia (e.g., grikes 5-m wide) or as in the karst

corridors of labyrinth karst (in these cases, the grikes are part

of a complex karren assemblage and cannot be picked out as

clearly delineated separate features).

Cutters are equivalent to grikes but developed entirely

below the (acidic) soil surface and are seen best when exposed

by quarrying. The location and overall vertical form is fracture

guided but additional subsoil processes modify the simple

canyon form with rounded pits, pinnacles, and cavernous

karren (below).

Figure 15 Splitkarren, Burren, Co. Clare, Ireland.

Figure 14 Centripetally draining rundkarren from Hutton RoofCrags, Lancashire, UK.

Figure 16 Grikes and clints of NW Burren, Co. Clare, Ireland, inexposed glacially scoured, relatively massive bedding plane, guidedby parallel joint sets. Some of the grikes have a partial fill of soil andvegetation. The upstanding rock pillar is B2-m high.


The positive form left by the development of grikes is the

clint, the shape of which in plan view depends on the pattern

of guiding joints (Figure 18). With moderately thick beds and

wide joint spacing, clints are large and may harbor solution

pans. With increasing joint frequency, the clints become

smaller (and the grikes correspondingly shorter). With thinner

beds, the clints are likely to become broken up and disinte-

grate into a rubbly surface called ‘shillow’ or ‘clitter’.

6.12.2.12 Subcutaneous Karren (Bodenkarren)

Dissolution underneath a cover (usually of acidic soil, but it

can be of sediment or organic material – hence the advantage

of using the general term ‘subcutaneous’ in favor of ‘subsoil’)

gives a fundamentally different control compared with dis-

solution on a bare-rock surface. Obvious differences are the

continuous wet conditions, the maintenance of wetness over

the whole rock surface, the capillary forces that govern flow

between cover and rock, and the absence of open sheet or

channel flow. Dissolution under a cover can be several times

higher than on an open surface – partly because there is more

time of contact for reactions, but mainly because biogenic

acidification of solvent can be magnified (this is extreme

under hot, humid tropical climates – see Folk et al. (1973)).

Morphology is still governed by gravity (water still tends to

flow downwards) and lithological factors (fractures still tend

to govern location of maximum dissolution) but all the re-

sultant forms are modified by the subcutaneous conditions.

The simplest difference between subaerial and subcutaneous

dissolution is apparent from the smooth cuspate, arcuate, and

roundly runneled surfaces exposed by recent soil erosion in

contrast to the more selectively corroded, angular, sharply

etched subaerial surfaces. The result of dissolution by perco-

lation water depends on how the flow impinges on the rock,

and on the hydraulic gradient. Percolation water moving as a

sheet along the contact of high-angle rock and soil creates

smooth undulating surfaces, and sometimes subsoil ripples

(Figure 19). More focused percolation moves in channels

to create rundkarren. More diffuse percolation and a lower

hydraulic gradient produces cavernous karren.

6.12.2.13 Karren Wells

Karren wells are shafts in the epikarst that connect to small

caves, and form typically where several rundkarren merge

(Figure 20). They vary greatly in size and, although commonly

vertical, can be inclined. These are generally produced at the

junction of two or more joints, but sometimes by over-

deepening of kamenitzas to intersect the underlying bedding

planes. They may form on bare surfaces but are more likely

formed under soil (and exposed by soil erosion).

Figure 17 Curved grikes and complex clints on stromatoliticdolostones of Grand Rapids, Manitoba, Canada.

Figure 18 The jointing pattern on Hutton Roof Crags, Lancashire,UK, creates diamond-shaped clints on the 451 dipping slope (the clintsurfaces are decorated with rinnenkarren).


6.12.2.14 Cavernous Karren/Subsoil Pits (KavernosenKarren)

Less-focused percolation produces a generalized rounded pit-

ting called ‘cavernous karren’ that sometimes makes a kind of

bone yard or spongework of interconnecting pits. (When

emergent, these forms may be confused with tafoni of surface

alveolar weathering.) Where percolation waters sit on a flat

surface they may carve rounded basins (‘subsoil cups’ or

‘covered kamenitzas’).

Some of the subcutaneous features are similar, and prob-

ably form in a similar manner, to cave paragenetic features,

when sediment forces flow against the rock face. On rock

faces, small anastomizing networks develop. Features of

paragenesis can also develop on underhangs, including para-

genetic-like pendants or scallops, and subsoil notches.

The relative relief in subcutaneous karren gets more ex-

aggerated the higher the acidity, gentle cusps giving way to

deep runnels and pipes in the most acid conditions. Although

subcutaneous corrosion can attack the rock from many dir-

ections, vertical downcutting of the joints is still most likely,

creating cutters and leaving interjoint positive forms that are

commonly rounded pinnacles (Figure 21).

6.12.2.15 Solution Notches (Korrosionskehlen) andSubcutaneous Half-Bells

Corrosion notches (Figure 22) form where aggressive water or

an acidic soil lies in contact with an emergent cliff face. The

upper edge is sharp but the lower edge rounded and the form

is unrelated to bedding plane corrosion. Some may be

only shallow horizontal recesses, but some swamp notches are

extremely deep – for example, the notches from valley-bottom

Figure 19 Subsoil ripples on side of an emergent block, Chillagoe,Australia. The line demarcating the former soil level is clear, the rockabove sharply etched and below smooth.

Figure 20 Vertical rundkarren around a deep karren well thatconnects into a cave system, Yorkshire, UK.

Figure 21 Rounded subcutaneous karren and cutter emergent froma terra rossa cover, exposed in a road cut, Istria, Croatia. Theemergent forms are rounded pinnacles.


wetlands in the Inuvik region of Nunavit, Canada, cut more

than 1-m deep horizontally into the dolostones, but only

about 20-cm high (Ford and Williams, 1989).

Subcutaneous half-bells are akin to solution notches. They

also form just below the surface of the soil, but they develop

from focused flow where a subaerial channel delivers water to

the soil at a rate that exceeds the normal percolation rate. The

solvent, thus, remains in the soil upper horizons, carving a

rounded grotto, wider at the top and tapering with depth.

6.12.2.16 Solution Pipes (Geologische Orgeln)

Unfortunately, some publications use the term ‘solution pipe’ as

synonymous with karren well, whereas, as the discussion below

shows, solution pipes, being essentially eogenetic and synge-

netic in origin, are fundamentally distinct from karren wells.

Solution pipes are smoothly cylindrical pipes/chimneys in

soft, poorly cemented, porous rock, such as calcarenites

(Figure 23). They are invariably vertical, regardless of sedi-

mentary dip. They vary in size but are typically 0.5-m wide

(ranging from 0.2 to 1 m) and 2–5-m deep (but can be up to

20-m deep). They can be isolated but are commonly in widely

spaced sets. They commonly have cemented rims and linings

and are filled, generally with the overlying material, perhaps

sands, perhaps terra rossa. Some pipes are filled with a

modified version of the host material, preserving ‘ghost’ im-

ages of original sedimentary structures. The most significant

feature is that solution pipes form in rocks such as young

calcarenites that have high primary porosity, are commonly

quite heterogeneous, and have not undergone significant

diagenesis. Pipe formation is syngenetic in that it occurs by

concurrent dissolution and precipitation, at the same time as

sediment is being cemented into rock. Focused vertical vadose

water percolating through the porous sediments dissolves

calcareous material and then reprecipitates it at the pipe edge

to form the linings and rims.

6.12.2.17 Spitzkarren

Spitzkarren are small to medium sized, pointed, and vaguely

horn-shaped or pyramidal remnant features. There is no

unique mechanism for formation. On bare rock, they may

result from backcutting of several sets of rillenkarren around

a boss leaving a spike. Under a vegetation cover, they may be

carved by biokarstic pitting of the surrounding surfaces. Some

of the spikiest spitzkarren is produced by biokarstic processes

in low-lying swampy environments on eogenetic rock. The

spikiness is partly from the irregular biological action, but also

from the inhomogeneous rock. If it is clearly of biokarstic

origin, then spitzkarren is generally called by the general term

for karren carved by action of plants – ‘phytokarren’. In the

example shown in Figure 24, the spikes are the result of en-

hanced dissolution from mixed salt–fresh water (sea spray and

rain) driven by on-shore trade winds.

6.12.2.18 Pinnacles

Pinnacles are also spiky pointed features, but at a much larger

scale (e.g., the pinnacles of Mulu may be 50-m high) and of

more complex origin. Pinnacles are the residual positive forms

left after downcutting of grikes, cutters, and subcutaneous

runnels. They may themselves have clusters of smaller spitz-

karren on top, as well as rinnenkarren and wandkarren on the

sides (Figure 25). Pinnacles have a complex history of at least

two stages of development, the first as rounded subcutaneous

forms and the second as emergent subaerially sharpened

forms (Figure 26). To some extent, the very process of dis-

solution of grikes itself causes the downward migration of the

soil surface and the emergence of the positive forms. However,

the tallest pinnacles are associated with uplift or lowering of

base level. The largest pinnacles are in thickly bedded, mas-

sive, strong, chemically pure rocks with well-spaced joints.

6.12.3 Karren Assemblages

The account above may give the impression that karren can be

neatly categorized and described. In reality, the features are

commonly very complex, many of them polygenetic in origin.

At the landscape scale, they may be part of a large area of bare

Figure 22 Corrosion notch at the foot of a formerly subsoil pinnacle(left of the person’s foot), which itself shows the emergentrundkarren now sharpened by subaerial corrosion, New Zealand.

Figure 23 Solution pipes in coarse-grained poorly lithified beachdeposits Punta Higuero, Puerto Rico, exposed by cliff fall. Twogenerations of pipes can be seen (lying on their sides, the biggerones highlighted with white arrows), each created as the overlyingmaterial was being deposited.


rock with assemblages of karren of many types, called kar-

renfields. Although the variety of individual karren features

displayed in any one karrenfield may appear to be over-

whelming, in reality certain features tend to occur together in

assemblages. These are only briefly discussed below, being

further developed in other sections of this volume.

Karrenfields developed on laterally scoured bedding planes

that have been dissolutionally modified into clints and grikes

are called pavements (Williams, 1960; Figures 10 and 16). The

lateral scour is most commonly caused by glacial action but

any mechanism such as rapid lateral retreat of slopes may

leave behind a pavement (examples of this can be seen in

Chillagoe, Queensland, Australia). Suites of pavements on

several bedding planes, separated by scarps, usually fit into

two basic types depending on relationship of topographic

slope and regional dip. This may be in cuestas or in steps

(the German terms for these – Shichtreppenkarst and

Schichtrippenkarst, respectively – being unfortunately similar

and confusable). Pavements from glacial scour are best de-

veloped where stratal dip is oriented in the direction of ice

movement. The karren of pavements include clints, grikes,

rillenkarren, rinnenkarren, karren wells, and trittkarren.

The overall structure of the clints and grikes reflects the

overall geological structure, the patterns of tension, fractures,

etc. Some of the grikes on the outer edges of scarps may be

caused by pressure release. If glacial scour was not complete,

some may inherit preglacial karstification.

Recent studies of the pavements of England and Ireland

(Gines et al., 2009) suggest that some are more polygenetic

than expected. Many are partly exhumed paleokarsts that have

resisted glacial scour, especially on the inner edges of scars

(Figure 27).

The end product of pavement development may be a

generally degraded surface of rock rubble and vegetation

patches. If grikes enlarge with minimal modification of the

clint, then the end result is a ‘ruiniform’ karrenfield of

weathered stacks (Figure 28). The ruiniform landscape of

the Venetian Prealps has been called ‘Rock Cities’; in this

case, the clint surface is made up of cherty nodular impure

micritic limestone that is resistant to dissolution. The less-

resistant underlying beds lead to development of mushroom

forms.

Some of the most spectacular karrenfields in the world

are towers or dissected plateaus, made up of pinnacles, giant

grikes, kamenitzas, and other karren. These are treated in

detail by Knez (see Chapter 6.13).

The karren fields of the west coast of Patagonia, Chile are

unique because the forms are dominated by the extraordinarily

Figure 24 Spitzkarren on eogenetic limestone of Bonaire,Netherlands Antilles. Here, the spikes are angled in the direction ofthe prevailing wind and carved by the enhanced aggressivity of mixedsea spray and rain, driven by strong winds.

Figure 25 A small outcrop of pinnacle karst, Laguna Guaniguilla,Puerto Rico. The field of view is about 2-m high.


high rainfall and extreme windiness (Gines et al., 2009).

These are the best examples in the world of hydro-aeolian

dissolution and new forms are being found on every exped-

ition. Everything here is magnified – the rinnenkarren and

wandkarren are giant, 100–300-m high, some canyon-like

forms 4–8-m deep and 1-m wide; the meanderkarren have

amplitudes of several meters; and overall postglacial surface

lowering is 80–170 cm. The force of the wind often overrides

gravity, creating wind-oriented forms rather than gravito-

morphic forms. In the case of Patagonia, the obstacle marks

that develop on the lee side of protruberences (elongate

wedges dubbed ‘Rock Comets’, essentially crag and tail fea-

tures similar to the Lame Dentates mentioned above, but on

horizontal slopes rather than vertical) are decimeters in size.

Figure 29 shows tiny wind-oriented obstacle marks developed

in a very different situation, on dolostones of Dodo region in

subarctic Canada.

Another type of karren assemblage is the nival karrenfield.

These occur in arctic and alpine regions with significant

winter snow cover. Trittkarren, trichterkarren, and sharpened

edges have been taken as diagnostic of dissolution under

a snow cover. They certainly are more common in areas of

snow, but the presence of similar forms in wet and windy

but non-snowy environments does rather give the lie to this

assertion.

Figure 26 Rounded pinnacles emergent from under a soil cover, WeeJasper, Australia. The surfaces more recently soil covered are stillsmooth, those less recently covered have been sharpened byrillenkarren (Australia has some of the biggest rillenkarren in the world).

Figure 27 Scar Close, Yorkshire. The inner edge of the pavementstill shows the circular solution pipes (each circular depression isabout 1 m in diameter) of the partly glacially truncated paleokarst.The outer part of the pavement has more normal rectangular clintsand grikes.

Figure 28 Example from Scar Close, Lancashire of pavementdegraded into the beginning of a ruiniform landscape. The wallsexposed above the soil are up to B1-m high.

Figure 29 Tiny wind-oriented obstacle marks in dolostones of theDodo region, subarctic Canada (lens filter is 5 cm in diameter).


6.12.4 Classification

Classification is challenging because of the great number of

forms, many of which are gradational to other forms and

of various sizes. Also, challenging is the great variety of

terminologies from different studies, in different languages,

for forms that may turn out to be identical. The simplest

classification is by morphometry and size – but that is only

descriptive and has only moderate genetic implication. Clas-

sification by genetic factors is preferable but prone to error if

the genetic mechanisms are not fully known (and inferring

process on the basis of form alone may be dangerous). So, we

are generally left with classification schemes that are partially

morphometric and partly genetic (see examples in Ford and

Lundberg (1987), Ford and Williams (1989), Fornos and

Gines (1996), and Gines et al. (2009)).

Morphometry divides features according to basic form –

circular or linear (with tacit implications about the nature and

duration of the rock-solvent contact) – and according to size –

micro, meso, macro, etc. Size depends on the dimension

chosen, so size is usually indicated based on the smallest di-

mension. Micro forms are o1 cm (e.g., rillensteine and some

pits). Small forms are 41 cm but o1 m, and include the

majority of karren forms. Large forms are 41 m (e.g., clints

and pinnacles). An indication of whether the form is negative

(erosional) or positive (remnant) is not of much value be-

cause only clints, spitzkarren and pinnacles are positive.

The most basic of genetic divisions is according to extent of

cover – bare (or ‘free’) karren, partly covered (‘half-free’), and

completely covered – again with tacit implications about

the process. Simple hydrodynamic controls are most likely

expressed on bare karren, where solvent may remain in con-

tact with rock for only a short time (‘hydrodynamic’ means the

way that fluid flows, or the forces, energy, and pressure of

liquid in motion). Bare karren is the most likely to show the

effects of microclimates (such as differential drying and varied

microbiological colonization) and, thus, most likely to show

the sharp etching of distinct differential corrosion. For covered

karren (which is generally subdivided according to nature of

cover into acidic cover – which yields karren – vs. carbonate

cover – which yields no karren), the solvent is in contact with

the whole rock surface for longer and is itself acidified by

biogenic CO2. Here, hydrodynamic controls are subdominant

to lithological and hydraulic controls.

Although the distinction between bare and covered is very

useful, it does not acknowledge explicitly the underlying,

more basic controls on the dissolution process. For this rea-

son, classification according to hydrodynamic control versus

lithological control is preferable, although it does ignore

chemical controls. Further categorization according to the

behavior of the solutional agent is useful. Adding a

polygenetic category acknowledges the generally non-simple

nature of most karren.

6.12.4.1 Classification Based on Physical and ChemicalProperties of Solvent and Solute

Dissolution can only take place where rock and solvent meet,

so the movement of that solvent is clearly an important

control (i.e., hydrodynamics). The forces, energy, and pressure

of fluid in motion includes direct raindrop impact (rillenkar-

ren and rainpits), sheet flow on a surface (solution bevels in

their various forms), and open channel flow (rinnenkarren

and variants thereof). Aeolian control is exerted here in how it

forces fluid to flow (perhaps constraining flow as a sheet when

it would normally separate into channels, or perhaps in-

hibiting free gravitational drainage). Surface tension (perhaps

augmented by rapid evaporation) may serve to hinder flow

(rillensteine).

The presence of a cover also hinders free flow. It either

forces flow to the very narrow contact zone between the cover

and the rock (subcutaneous scallops) or it forces flow to move

by percolation in the interparticle pore spaces and channels.

Percolation and capillary flow serve to keep the covered rock

surfaces in long-term contact with the solvent. A biological

cover (even on the microscopic scale) and a snow cover also

serves in this way (although the snow cover acts for only some

of the time).

The chemical properties of that solvent are the next most

important control (i.e., aggressivity). Simple rainwater has

little dissolutional potential. Modifications of the solvent in-

clude enhancement of aggressivity (e.g., by absorption of CO2,

from soil, by contact with biological material, or from snow),

or reduction of aggressivity (by contact with soluble material).

Looking at the chemical and physical properties of the

solute (the material to be dissolved) provides the third level

of control. Of the rock factors, rock chemistry is important in

that it must be soluble, or at least some part of it such as

interclast cement (which explains why nonkarst rocks such as

some sandstones may display dissolutional karren features).

The extent of lithification is important in that eogenetic rocks

dissolve perfectly well but do not develop neat karren features.

Rock homogeneity generally governs the regularity of the

karren and certain karren (mainly rillensteine) will only be

expressed on the finest-grained rocks.

The most important of the rock features is fracture control.

This is the biggest control of the largest forms because it acts

most strongly under a cover and the largest of the karrenfields

generally form initially under a cover. Thus, fracture control

governs, grikes, clints, cutters, and pinnacles.

These four main controls govern the processes of karren

formation. Obviously, other factors may be important to the

final morphology. Many are of polygenetic origin, several of

these basic controls operating at different times in different

ways. Many karren features are inherited from another land-

scapes such as glacial scour forms or paleokarst forms. The

classification scheme presented here (Figure 30) is an attempt

to present the forms with the practically useful descriptions of

form and size but also to include all the known genetic factors.

6.12.4.2 Important Karren Regions

The list of important karren regions is, of course, limited by

what has been published, what is accessible, and what has

been explored by karst geomorphologists. It is highly likely

that important karren regions in more remote regions will

come to light in future years. There is generally a bias toward

English-language reports and toward well-studied regions,


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such as Europe (see Fornos and Gines, 1996; Gines et al.,

2009). For this short review, the list below cannot be

exhaustive.

The most important karren regions are always also im-

portant karst regions (e.g., the Mulu karst of Sarawak) – but

many important karst regions have poorly developed karren

(e.g., the sinkhole plain of Kentucky). In western Europe,

Ireland’s Burren and NW England have excellent clint and

grike pavements. The European Alps have many widespread

and varied suites of karren, such as central Switzerland, the

Italian Dolomites and the Austrian Dachstein, as does the

Classical Karst region of Slovenia and Croatia. In the Medi-

terranean area, the Pyrenees, and the island of Mallorca have

beautiful karrenfields. Surprisingly, some areas of extensive

tropical karst have unexceptional karren, for example, the

Caribbean islands (and this is probably governed largely by

the lithology of the young rocks), whereas others have

extremely impressive karren, such as the Tsingy regions

of Madagascar, northern Australia’s Chillagoe and Kimberley

regions, South-East Asia’s Sarawak region, Mt. Kaijende of

New Guinea, and south China’s Yunnan province. Temperate

regions with impressive karren include parts of New South

Wales, Australia, and New Zealand’s Mt. Owen and Arthur

region (Kahurangi National Park). Madre de Dios Island,

Patagonia has recently come to light as one of the more

interesting karren regions where wind is an important control

on morphology. Although most subarctic and arctic regions

do not display good karren, there are a few, such as Dodo and

Nahanni, Canada, where frost action is not dominant and

karren can still occur. Although the vast majority of karren

fields are developed on carbonate or evaporite rocks (tradi-

tionally viewed as the ‘soluble’ rocks), some sizable examples

occur on quartzites (e.g., Transvaal, South Africa) and on

sandstone (e.g., the Tepuis of Venezuela).

6.12.5 The Future

Modeling and biokarst are probably the two ‘hottest’ topics in

the field of microsculpturing of solutional rocky landforms.

Future directions for research may address some of these

questions:

• What is the connection between process and form?

• Can modeling, either physical (such as plaster block ex-

periments) or mathematical (such as computer modeling),

elucidate process?

• Can field studies be tailored to isolate environmental

controls (such as rainfall intensity vs. quantity)?

• Can the application of statistical methods improve our

understanding of significant differences?

• Can we use principles of ecology to elucidate karren–

environment relationships, and karren development?

• To what extent is organic activity an inherent process

in karren formation (i.e., in all karren and not simply

biokarst)? Can this be quantified?

• What is the explicit mechanism by which biological action

affects corrosion/denudation?

References

Bogli, A., 1951. Probleme der Karrenbildung. Geographica Helvetica 3, 191–204.Bogli, A., 1960. Kalklosung und Karrenbildung. Zeitschrift fur Geomorphologie

Supplement 2, 4–21.Bogli, A., 1980. Karst Hydrology and Physical Speleology. Springer, Berlin, 284 pp.Bogli, A., 1981. Solution of limestone and karren formation. In: Sweeting, M.M.

(Ed.), Karst Geomorphology. Benchmark Papers in Geology 59. Hutchinson RossPublishing Company, Stroudsberg, PA, pp. 64–89.

Folk, R.L., Roberts, H.H., Moore, C.H., 1973. Black phytokarst from Hell, CaymanIslands, British West Indies. Geological Society of America Bulletin 84,2351–2360.

Ford, D.C., Lundberg, J., 1987. A review of dissolutional rills in limestone andother soluble rocks. Catena Supplement 8, 119–140.

Ford, D.C., Williams, P., 1989. Karst Geomorphology and Hydrology. Unwin Hyman,London, 601 pp.

Fornos, J.J., Gines, A. (Eds.), 1996. Karren Landforms. Servei de Publicacions,Universitat de les Illes Balears, Palma de Mallorca, 450 pp.

Gines, A., 2004. Karren. In: Gunn, J. (Ed.), Encyclopedia of Caves and KarstScience. Fitzroy Dearborn, New York, NY and London, pp. 470–473.

Gines, A., Knez, M., Slabe, T., Dreybrodt, W. (Eds.), 2009. Karst Rock FeaturesKarren Sculpturing. Carstologia 9, Zalozba ZRC/ZRC Publishing, Ljubljana,pp. 562.

Glew, J.R., Ford, D.C., 1980. A simulation study of the development of rillenkarren.Earth Surface Processes and Landforms 5, 25–36.

Jakucs, L., 1977. Morphogenetics of Karst Regions. Adam Hilger, Bristol, 284 pp.Jennings, J.N., 1985. Karst Geomorphology. Basil Blackwell, Oxford.Sweeting, M.M., 1972. Karst Landforms. Macmillan, London.Trudgill, S.T., 1985. Limestone Geomorphology. Longman, London and New York,

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University Press, Oxford.Williams, P.W., 1960. Limestone Pavements. Transactions of the Institute of British

Geographers 40, 155–172.

Relevant Websites

http://www.doc.govt.nzDepartment of Conservation; Natural sites of high priority for immediate WorldHeritage listing.

http://www.fotopedia.comfotopedia; Ankarana Reserve; South China Karst.

http://www.gsi.ieGeological Survey of Ireland; The Karst of Ireland.

http://www.ijs.speleo.itInternational Journal of Speleology; IJS Photo Gallery.

http://www.limestone-pavements.org.ukLimestone Pavement Conservation.

http://www.limestone-pavements.org.ukLimestone Pavement Conservation; Geology.

http://bioref.lastdragon.org/habitats/LimestonePavement.htmlLimestone Pavement; Images of British & Irish biodiversity.

http://www.malaysiasite.nlMALAYSIA; The Pinnacles: the famous Pinnacles of Mulu National Park.

http://www.world-heritage-tour.orgPatrimonium-mundi.org: UNESCO world heritage site in panophotographiesimmersive and interactive panoramic images; Earth; Asia, China.

http://science.jrank.orgScience Encyclopedia; Karren.

http://www.ee.usyd.edu.auThe University of Sydney: Electrical and Information Engineering; SydneyUniversity Speleological Society.

http://www.travel-images.comTravel Images: The Global Image Bank; Images of Madagascar.

http://zuzutop.comzuzu.com; The Fascinating Stone Forest on Madagascar.


Biographical Sketch

Joyce Lundberg was educated in Trinity College, Dublin, Australia National University, Canberra (MSc), Bristol

University (PGCE), and McMaster University, Hamilton (PhD). After a short career teaching high school biology,

music, and art in England and Kenya, she joined the faculty of Carleton University in 1990. Her research interests

include field-based studies and lab-based (mainly geochronology) studies of karst geomorphology (both arctic

and tropical), speleology, cave paleontology, sea-level change, and paleoclimatology. Of late, she has become

interested in zoogeomorphology in caves.


Documents

6.12 Microsculpturing of Solutional Rocky Landforms · 6.12 Microsculpturing of Solutional Rocky Landforms J Lundberg, ... they do develop on less-soluble rocks in ... The various