Download PDF - Speleogenesis

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NCKRI Special Paper No. 1
through vadose, each subsequent setting may contribute
substantially to cave development, sometimes adding
significant volume to a cave. In this sense, both
mechanisms questioned above with respect to the origin of
maze caves, floodwater (backflooding) dissolution and
dissolution by recharge from overlying permeable caprock,
may certainly contribute to cave development, being
operative during the respective transitional stages.
However, the rapidly growing body of evidence from
regions around the world (see Section 4.5) leads the author
to believe that most known maze caves were formed in
confined conditions, as the product of ascending hypogenic
transverse speleogenesis.
4.4 Cave morphology
As with macro-morphological features (cave patterns),
the meso-morphology of caves is the most important
characteristic of caves indicating their origin. This is
simply because a cave is primarily a form, produced by
interaction between groundwater and its environment. The
analysis of spatial and temporal relationships of different
cave morphologies in the context of the regional
geomorphic and hydrogeologic evolution is the most
powerful tool for inferring cave origin.
As discussed in the preceding section, hypogenic
caves may have variable patterns, controlled mainly by
local geological and structural conditions (which also
determine the mode of recharge from below). Despite
this variability, meso-morphological features of hypogenic
caves exhibit remarkable similarity among caves and
comprise a specific set of forms.
Morphologic suite of rising flow (MSRF)
Some medium-scale morphological features of
ascending hypogenic transverse caves have specific
hydrologic functions and usually occur in a characteristic
suite of forms; therefore they are particularly indicative of
the mode of cave origin. Their occurrence in a suite makes
the interpretation of their hydrologic function and origin
especially unequivocal. Such a regular combination of
forms, called here the morphologic suite of rising flow
(MSRF), was first recognized in western Ukrainian
gypsum mazes unequivocally established as ascending
hypogenic caves, and subsequently found in many maze
caves around the world in both limestone and gypsum.
Some of the caves, where MSRF has been recognized,
were previously attributed to hydrothermal, sulfuric acid or
gypsum speleogenesis, or (maze caves) were viewed as
developed by backflooding, by recharge through a
permeable caprock, or not clearly interpreted genetically.
The recognition of MSRF in such a great variety of caves,
which have been previously seen as genetically different,
suggests a common origin and is the strongest argument in
favor of the dominant role of hydrogeological factors in
speleogenesis, i.e. the type and regime of groundwater
flow and the modes of recharge and discharge.
The morphologic suite of rising flow consists of three
major components: 1) feeders (inlets), 2) transitional wall
and ceiling features, and 3) outlet features (Figure 19).
Figure 19.
The morphologic suite of
rising flow, diagnostic of
confined transverse origin
of caves. The geometry
of a cave segment, the
relative scale of features
and hydrostratigraphy on
this diagram is directly
representative of Ozerna
Cave in western Ukraine.
However, the diagram is
generic and elastic; it can
be stretched vertically,
and a complexity can be
added to account for
multiple lateral stories.
The arrangement of the
forms will repeat itself on
each story, and functional
relationships between the
forms will remain the
same.