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Fig. 20. Fibrous texture: (a) encrusted Vaucheria filaments, L´ ˇky top point, December 2003; (b) encrusted
cyanobacterial filaments, L´ ˇky E point, tufa formed on limestone tablet between August 2002 and October 2003; (c)
sample built of Vaucheria filaments, macroscopic view, L ´ˇky top point, June 2003; (d) crystal size increases outwards
the Vaucheria filament, L´ ˇky top point, October 2003; (e) loosely cemented cyanobacterial filaments showing parallel
orientation L´ˇky E point, tufa formed on limestone tablet between August 2002 and October 2003; (f ) loose crystals
(arrows) trapped and cemented between filaments, the same sample as in e; a, b, d, f - SEM images, e - thin section.
reflects variations in primary density of algae inhab-
iting the surface of the growing tufa. More than 60
couplets of compact and dense laminae are present
in tufa that grew on a limestone tablet exposed
between August 2002 and October 2003. The lami-
nated tufa is underlain by tufa with crystalline
texture, so its deposition took place only for a part
of the time of the tablet exposition.
The third type of lamination is manifest by con-
centration of detritic non-carbonate components or
organic matter. When detritic components are
deposited within porous tufa, they are dispersed.
The tufa that grew at the Karw´w cascade through-
out the whole experiment serves as an example.
Conversely, compact, crystalline texture of tufa
favours the origin of clearly visible laminae, built
of fine-grained detritic components (Fig. 22a - e).
The laminae drape underlying crystals and accentu-
ate the shape of crystal terminations. The laminae
range in thickness from less than 0.5 to 5.0 mm
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