Geology Reference
In-Depth Information
mostly by the bryophytes (Fig. 4a, c, d). The bryo-
phytes and other organic entities, which are in
growth position, are main components of the phyto-
herm framestone facies (Fig. 4c, d). The exposed
surface is green whereas the inner parts of the tufa
are yellow because of the calcite cement that coats
the surfaces.
There is an overhang on the uppermost part of
the waterfall face (Fig. 4a, c) from which blocks
of variable sizes commonly detach and fall to the
foot of the waterfall. Blocks fell and a fracture
was created in the overhang when the Buldan earth-
quakes of 5.2 - 5.6 magnitude occured close the
Buldan town between 23 and 26 July in 2005
(Kumsar et al. 2008, p. 95 - 98).
The springline tufa body contains numerous
primary cavities up to cave size in some cases.
There are two main caves in the tufa site (Fig. 1c).
One of them is under the splash zone within the
active waterfall area (Fig. 3). A pool at the cave
bottom is about 10 m wide and filled by percolating
and drip waters (Fig. 4f ). The second cave, to the
NE, is located in the inactive tufa body that is
close to Sp-2 (Fig. 1c). The pool in the bottom of
this cave has been partly filled by wet lime mud
and tufa fragments. Both caves have been partly or
completely coated by various speleothems (Fig. 4f ).
evidence of earlier deposits, although some sites
as in the Tajuna valley (central Spain) demonstrate
considerable preservation potential. As the river
incises into its valley, there is often a corresponding
reduction in the elevation of springlines along the
valley size. There is, therefore, the possibility that
deposits high on the upper valley sides are older
than those lower down the slopes. In the case of
multi-spring resurgences, age relationships between
individual tufa mounds are more complex (Pedley
et al. 2003).
At the G ¨ney perched springline tufa site, tufa
lobes at different levels have coalesced each others.
There are inactive lobes at various elevations above
and below of the active waterfall area. Therefore, a
regular downslope decrease in ages of the tufa lobes
was not expected. The preliminary
14
C dating of the
some extinct tufa samples taken randomly gave
14
C
age in the range from 2000 yr BP to 5800 yr BP
(Table 2). The
14
C results are not corrected for the
initial
14
C activity (A
o
) of the carbonate (the 'reser-
voir' effect). According to the
14
C age data, extinct
tufas are not older than Holocene (Horvatin
ˇ
i
´
et al.
2005). Further age dating is required before the
precise ages of deposition can be determined.
Spring water physiochemistry
Lower slope area
There are four main springs (Fig. 1c) and many
smaller seeps in the G¨ney tufa site. The total flow
rate of the springs is about 80 L/s. The discharge
elevations are more or less the same for two springs
(Sp-2 at 415 m and Sp-3 at 417 m a.s.l.; see Fig. 1c
for spring location), whereas the other two discharge
at lower elevations (Sp-1 at 320 m and Sp-4 at 355 m
a.s.l.). The waters of Sp-2, Sp-3, and Sp-4 emerge
from the boundary between the tufa deposit and
schist - marble alternation forming aquifer rocks.
The spring water of Sp-4 reaches the active waterfall
area via a 140 m long channel. In-situ measurements
show that the water physiochemistry of springs
Sp-2, Sp-3 and Sp-4 are similar and that there are
not distinct seasonal variations.
Hydrochemical features of the tufa precipitating
waters are summarized in Table 1. The main spring
waters discharge at 18.7 - 18.8 8C (Table 1) through-
out the year. The water temperature of Sp-1 is lower
(15.9 8C in winter to 16.7 8C in summer) than the
others. The water temperature in the splash zone of
the waterfall lobe-top area shows a regular variation
that is linked to seasonal air temperatures. The seaso-
nal fluctuations in the water temperature are about
0.5 8C in January and November while 0.2 - 0.5 8C
in April and July. The biggest variation in water
temperature occurs in the waterfall area due to
water falling. The water temperature at the cascade
bottom was decreased 0.5 8C in summer, 2.1 8Cin
The lower slope (or distal slope) lies below the foot
of the waterfall where the slope gradient changes
abruptly. In plan view, the lower slope tufas are
fan-like and cover a broad area in comparison
with the waterfall. The most of these deposits are
composed of intraclast tufa. The lower slope depos-
its were exposed clearly along a road cuts approach-
ing from the Cindere dam to the south - southwest
and river bad (Fig. 4e). At the road cut surfaces,
the lower slope deposits are consist of dominantly
detrital tufas (Fig. 5a, e, h) and associated laminated
tufa in some places (Fig. 5b) and macrophyte frag-
ments eroded from the cascade area (Fig. 5d, e, h).
The detrital tufa deposits have changed from silt
to block in size. The light-coloured laminated tufa
facies is composed of bryophyte layers and they
should have been precipitated along flow paths on
the slope (Fig. 5b). The macrophytes (¼ phytoherm
framestone facies) in some cases are in-situ life
position on the lower slope (Fig. 5g).
Age relationships of the coalescent
tufa lobes
Perched springline tufas typically develop from
single or multi-spring resurgences emerging on hill
slopes. Subsequent valley incision may remove
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