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Depositional properties and geochemistry of Holocene perched
springline tufa deposits and associated spring waters: a case study
from the Denizli Province, Western Turkey
MEHMET ¨ ZKUL 1 *, AL ˙ G ¨ KG ¨ Z 1 & NADA HORVATIN ˇ I ´ 2
1 Pamukkale University Engineering Faculty Department of Geological Engineering,
20070 Kınıklı campus, Denizli, Turkey
2 Ruder Boˇkovi´ Institute, Zagreb, Croatia
*Corresponding author (e-mail: mozkul@pau.edu.tr)
Abstract: The G¨ ney waterfall area is a perched springline tufa site developed on the southeast
slope of the B ¨y¨ k Menderes River near G¨ney town, in the Denizli province, Western Turkey.
The site is 12 km away from G¨ ney and 72 km from the city centre of Denizli. The spring waters
emerge from the boundary between Palaeozoic marble and micaschist and precipitated tufa
deposits downslope at the altitudes ranging from 220 to 400 metres. The tufa deposits cover an
area of about 20 hectares. Flat upper surfaces of the deposits are indicative of mature stage. The
waters are of the Ca - HCO 3 type and supersaturated with respect to CaCO 3 . The stable isotope
values of the spring waters are 249.94 for d 2 Hand27.15 for d 18 O. The d 13 Candd 18 Ovaluesof
active and passive tufa samples are in the range from 29.13 to 26.0‰, and from 28.44 to
27.40‰, respectively. These isotopic values are typical for fresh water tufa. The passive tufas give
the 14 C age in the range from 2000 to 5800 yr BP. According to the 14 C age data, passive tufas are
not older than Holocene. The stable isotope composition is similar south European examples.
Tufa and travertine are common carbonate deposits
in Quaternary and present-day depositional systems
(Chafetz & Folk 1984; Ford & Pedley 1996; Guo &
Riding 1998; Arenas et al. 2000; Horvatin ˇ i ´ et al.
2000; Glover & Robertson 2003; Bonny & Jones
2003) and are known from Neogene and older
successions (Arp 1995; Evans 1999; Cole et al.
2004). In this paper, 'tufa' was considered as sub-
aerial deposits produced from ambient temperature
waters and contains typically the remains of
micro- and macrophytes, invertebrates and bacteria
(Ford & Pedley 1996; Arenas et al. 2000; Pedley
et al. 2003). On the other hand, travertine is hydro-
thermal in origin (Chafetz & Folk 1984; Guo &
Riding 1998; Minissale et al. 2002).
Ford & Pedley (1996) divided tufa deposits into:
(1) perched springline, (2) fluvial; (3) lacustrine; and
(4) paludal depositional systems. Subsequently,
Pedley (2009) added the cascade model. Perched
springline tufa deposits, which occur on valley slo-
pes in mountainous or hilly countries, are part of the
tufa depositional continuum (Ford & Pedley 1996;
Pedley 2009; Pedley et al. 2003). These deposits
have been used as indicators of palaeohydrogeo-
logical evolution in karstic massifs and used to
evaluate climatic change in the Mediterranean
areas (Mart´n-Algarra et al. 2003). Although
outlines of these deposits have been presented
previously in Pedley (1990), Ford & Pedley
(1996) and Pedley et al. (2003), there are few
well-documented sites (Andreo et al. 1999;
Mart ´ n-Algarra et al. 2003; Anzalone et al. 2007).
Although, the Denizli province in the western
Turkey is well-known for its travertine deposits and
associated geothermal fields (Altunel & Hancock
1993; G¨kg¨z 1998; ¸ im¸ek et al. 2000; ¨ zkul
et al. 2002; ¸ im¸ek 2003), there are also a few
tufa sites (Ceylan 2000; Horvatinˇi´ et al. 2005).
In this study, the depositional features and geochem-
istry of a unique example of perched springline tufa
deposits and accompanying spring waters near the
G ¨ney town, Denizli, SW Turkey are examined.
Location and geological setting
The site is located on the SE slope of the B¨y ¨k
Menderes river valley near the town of G¨ney in the
NW part of the Denizli basin, western Turkey
(Figs 1 & 2). The site is 12 km from G ¨ney and 72 km
north of the city of Denizli. Based on long-term data,
the mean annual temperature and the rainfall are
about 13.5 8C and 548.8 mm, respectively. The tufa
deposits rest on marble and schist of the Palaeozoic
metamorphic bedrock that belong to the Menderes
masif (Bozkurt & Oberh¨nsli 2001; Erdo˘an &
G ¨ng¨r 2004). The bedrock is unconformably
overlain by a late Miocene lacustrine succession
(Ko¸yi˘it 2005; Kaymak¸ı 2006; Al¸i¸ek et al.
2007) at higher altitude of 900 m where the Cindere
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