Lithostratigraphy and Sedimentological Characteristics of the Calciturbidites of the Babadağ Formation-Tavas Nappe (SW Turkey)

The Lycian Nappes contain slices of ophiolites and sedimentary rocks of various ages that crop out in SW Turkey. They evolved and were emplaced under the effect of the Late CretaceousMiocene compressional regime. The Tavas Nappe is part of the Lycian Nappes and contains Jurassic-Eocene sediments. The Babadağ Formation, forming the middle part of the Tavas Nappe, is composed of limestone at the base and various sized calciturbidites with chert intercalations in the upper part. The Standard Microfacies Classification (SMF of FLÜGEL, 2004) indicates that the entire unit was deposited mainly in a deep-shelf environment (Facies Zone – FZ-2), deep-sea (FZ-1), toe of slope (FZ-3) and on the continental slope (FZ-4). Calcite and quartz dominate the bulk mineralogy of the calciturbidites with higher SiO2 and CaO weight percentages than other major oxides. Additionally, the presence of Na2O, K2O, Al2O3, MgO, TiO2 and Fe2O3 is associated with the local sediment input. Tectonism and sea level fluctuations were the main triggering factors of the changes in the original depositional environment of the Babadağ Formation. Additionally, grain size and the amount of sediment input control the calciturbidite type and extension. Si enriched water circulation and Si and Ca substitution were responsible for the abundant chert formation during diagenesis of the units. Post depositional tectonic activities during transportation and emplacement of the nappes resulted in calcite filled cracks that cut both the calciturbidites and cherts. Study of the different nappe slices provides valuable information about synand postdepositional changes of the lithostratigraphic units. Provence Basin, Turonian­Cenomanian, France (REIJMER et al., 2008, 2012; REIJMER et al., 2015a, 2015b); the Late Triassic­ Early Jurassic of Northern Hungary (HAAS et al., 2010); Jurassic Tethys Oceanic Carbonate deposits of Eastern Alps­Switzerland (EBERLI, 1987); the Early Cretaceous of the Manim unit, West­ ern Carpathians Slovakia (MICHALIK et al., 2012); the Late Cretaceous of the Ionian Basin­Central Albania (DEWEVER et al., 2007) and the Cretaceous of the Othris Mountain­Hellenide zone and Eastern Greece (PRICE, 1977). Some older calciturbi­ dites were reported in different countries; the Silurian­Devonian calciturbidites of the Barrandian Region­Czech Republic, (VA­ CEK, 2007); the Early­Middle Triassic Sumeini Group, Maqam Formation, northernmost Arabian Carbonate Platform (WATTS, 1987); and the Triassic Pedata / Potschen Formation calciturbi­ dites­Austria (REIJMER et al., 1991). In Turkey, ROBERTSON & WOODCOCK (1981) docu­ mented the Upper Triassic calcareous clastics and the Jurassic­ Lower Cretaceous siltstone­radiosphere­chert­mudstone­lime­ stones and black shales in Antalya­SW Turkey. SOFRACIOĞLU & KANDEMİR (2013) and SARI et al. (2014) reported the Upper Mesozoic calciturbidites in the Eastern Pontides­NE Turkey. ÖZCAN et al. (2012) mentioned the Upper Cretaceous­Eocene pelagic micrites and calciturbidites of the Black Sea shoreline and the Western Pontides–N Turkey. SOLAK et al. (2015) docu­ mented some Upper Cretaceous calciturbidites in the Bornova Flysch Zone in the Manisa­Spil Mountain–W Turkey (Fig. 1). Article history: Manuscript received December 19, 2019 Revised manuscript accepted October 14, 2020 Available online February 28, 2021


INTRODUCTION
Calciturbidites occur in various sedimentary environments such as continental slopes, toe of slope and single or multiple feeding submarine fans (WATTS, 1987;RUBERT et al., 2012;HAIRA BIAN et al., 2015). They can also be associated with different parts of carbonate platforms and platform margins (REIJMER et al., 2015a(REIJMER et al., , 2015b. The most important characteristic that distin guishes calciturbidites from siliciclastic deposits of the deep sea are the unique diagenetic process of dolomitization, silicification (chert layers or lenses) and micritization (EBERLI, 1991;RU BERT et al., 2012;GÜL, 2015). Calciturbidites are generally characterized by poor sorting, local inverse grading, diagenetic micritic layers embedded in the base and nodular silica layering (EBERLI, 1991). Chertification due to diagenesis affects the po rosity and permeability of the host rocks (McBRIDE et al., 1999;SALLER et al., 2001;BEHL, 2011). The sedimentation in carbo nate gravity systems is controlled by sea level fluctuations, source region, regional basin tectonics and slope characteristics (e.g., EBERLI, 1991;PAYROS & PUJALTE, 2008). REIJMER et al. (2015a) emphasized that calciturbidites are of interest to the oil and gas industry because of their porous and permeable granular structure.
Although studies have shown calciturbidites to crop out in various regions with different ages, fewer studies have been car ried out on the calciturbidites in comparison to siliciclastic turbi dites. The calciturbidites of the Babadağ Formation (in this manu script), are similar to the calciturbidites from the Southern

Abstract
The Lycian Nappes contain slices of ophiolites and sedimentary rocks of various ages that crop out in SW Turkey. They evolved and were emplaced under the effect of the Late Cretaceous-Miocene compressional regime. The Tavas Nappe is part of the Lycian Nappes and contains Jurassic-Eocene sediments. The Babadağ Formation, forming the middle part of the Tavas Nappe, is composed of limestone at the base and various sized calciturbidites with chert intercalations in the upper part. The Standard Microfacies Classification (SMF of FLÜGEL, 2004) indicates that the entire unit was deposited mainly in a deep-shelf environment (Facies Zone -FZ-2), deep-sea (FZ-1), toe of slope (FZ-3) and on the continental slope . Calcite and quartz dominate the bulk mineralogy of the calciturbidites with higher SiO 2 and CaO weight percentages than other major oxides. Additionally, the presence of Na 2 O, K 2 O, Al 2 O 3 , MgO, TiO 2 and Fe 2 O 3 is associated with the local sediment input. Tectonism and sea level fluctuations were the main triggering factors of the changes in the original depositional environment of the Babadağ Formation. Additionally, grain size and the amount of sediment input control the calciturbidite type and extension. Si enriched water circulation and Si and Ca substitution were responsible for the abundant chert formation during diagenesis of the units. Post depositional tectonic activities during transportation and emplacement of the nappes resulted in calcite filled cracks that cut both the calciturbidites and cherts. Study of the different nappe slices provides valuable information about syn-and post-depositional changes of the lithostratigraphic units.
In Turkey, ROBERTSON & WOODCOCK (1981) (Fig. 1). upper part of the Babadağ Formation require additional studies for a complete understanding of the carbonate gravityflow de posits.
Therefore, this study aims (1) to determine the detailed sedi mentological characteristics of the calciturbidites of the Babadağ Formation mapped as separated slices which together comprise the Tavas Nappe (Fig. 2), and (2) to unravel the depositional environment and controlling factors on the calciturbidite sedi ments.

GEOLOGICAL SETTING
SW Turkey contains three major geological units; the Beydağları Autochthone, the southern Menderes Massif and the Lycian Nap pes allochthones which crop out between these two autochthones (Fig. 1).
A Middle Jurassic age was proposed for the lower parts of the Babadağ Formation from radiolarians, benthic foraminifera in Tavas town (NW of the study area, Fig. 1; SOYCAN et al., 2009SOYCAN et al., , 2011SOYCAN et al., , 2015. In and around the towns of Fethiye and Köyceğiz (Fig. 2), the Babadağ Formation contains a Red Micritic Member at the base (including Ammonitico-rosso facies, locally breccia and chert, with the age of the member reported as Upper Toarcian), An oolite bearing Limestone member in the middle part (locally with peloid and nodular chert), has a reported age as Upper Dogger -Malm. Planktonicbenthic foraminifera and rud ist fragment bearing calciturbidites, Globotruncana sp. and chert bearing micritic limestone form the upper member of the forma tion (ŞENEL, 1997a(ŞENEL, , 1997b. This upper member of the Babadağ Formation including calciturbidites in Bozburun hill was studied in detail by GÜL (2015) and SARI (2017). SARI (2017) deter mined rudist shell fragments, benthic foraminifera (Orbitoidae) and rare gastropods (denoting the Late Maastrichtian) in the up permost part of the Bozburun hill, and defined several different forms of Globotruncana sp. from foraminiferal bearing wacke stones in the lower part (designated as being of Late Campanian Late Maastrichtian age).

MATERIALS AND METHODS
Four locations were selected in an attempt to achieve the objec tives of this study depending on forestrymaquis cover, road ac cess and exposure quality. A total of six sedimentary sections were measured at three different locations on Babadağ Mountain (Babadağ1, 50m; Babadağ2, 120 m; Babadağ3, 100 m; location 1 in Figs. 2, 4a), Ortaca town (Karadon1, 30 m; Karadon2, 20 m; location 2 in Figs. 2, 4b) and Yangı Village (Yangı section, 170 m; location 3 in Figs. 2, 4c). The Bozburun hill area is another study location (location 4 in Fig. 2). This region has already been documented in previous studies (GÜL et al., 2013;GÜL, 2015;SARI, 2017) due to its visible exposures in the field; however, the sedimentary textures, structures, and lateral and vertical facies changes have not been previously documented. Based on litho logical variations, sampling was carried out at 12 m intervals for mineralogical, chemical and petrographic analyses. A total of ninetynine samples were collected during the field studies (22 from the Babadağ Sections; 40 from the Karadon Sections; 23 from the Yangı Section, 14 from the Bozburun hill region); eightyfour thin sections (22 from the Babadağ Sections; 26 from the Karadon Sections; 22 from the Yangı Section, 14 from the Bozburun hill region) were prepared in the Thin Section Prepa ration Laboratories at the General Directorate of Mineral Re search and Exploration (MTA, Ankara, Turkey). The thin sec tions were examined under binocular petrographic microscopes and the grainsize of the calciturbidites was determined at the

Department of Geological Engineering at Muğla Sıtkı Koçman
University.
The mineralogical compositions of the samples were deter mined by the Xray diffraction method. Thirty representative sam ples of calcilutites and finegrained calcarenites (nine from the Babadağ Sections; eleven from the Karadon Sections; five from the Yangı Section, and five from the Bozburun hill region) were analy sed by a Panalytical Expert Pro diffractometer equipped with a Cu tube at 40kV voltage and 30mA current with a scanning rate of 2°/min at the MineralogyPetrography Laboratory at the General Directorate of Mineral Research and Exploration (Ankara, Turkey).
Xray fluorescence analysis was performed to determine the major oxide compositions of 30 calciturbidite samples. GÜL (2015) stated that microcrystallinecryptocrystalline cherts are present in the calciturbidite levels, however he did not address their diagenetic properties and textures. SEMEDS analyses through crosssections were carried out at the Research and Application Centre for Re search Laboratories at Muğla Sıtkı Koçman University (Muğla, Turkey). The specimens were sputter coated with gold (Emitech K550X Sputter Coating Systems). Samples were examined under a scanning electron microscope (SEM) (Jeol JSM7600F, Japan) at an accelerating voltage of 15 kV. Elemental characterizations of the samples were done using the SEM equipped with Energy Disper sive Xray Spectrometry (EDSOxford Instrument).

Lithostratigraphy of the Babadağ Formation
This study focuses on the calciturbidites of the Babadağ Forma tion and its lithological features. The Babadağ Formation is com posed mainly of calcilutite, calcisiltite, in some parts calcarenite and rarely calcirudite in its upper parts (ŞENEL, 1997a(ŞENEL, , 1997bGÜL, 2015;SARI, 2017).
Babadağ Sections: These sections were measured at Babadağ Mountain, which is located at 56 km south west of Fethiye Town (Fig. 2). In this region, the Babadağ formation con formably overlies the Ağaçlı Formation and is overlain by the Faralya Formation (Fig. 3). In addition, some levels of the Babadağ Formation are tectonically overlain by the Bodrum Nappe. The large part of Babadağ Mt. is covered with forests, making it difficult to find a straight section to measure (Fig. 4a). Some exposures were difficult to reach due to lack of proper roads and the risk of rock falls. Observations showed that the unit was faulted, folded, overturned, and highly deformed. Strati graphic sections were measured from the possible top point of the Babadağ Mountain, through the pathways opened for Babadağ paragliding centre.
The Babadağ1 section (50 m) measured (Fig. 4a1) at the up per part is considered to be the youngest part of the Babadağ For mation (Fig. 5). The Babadağ2 section (120 m) (Fig. 4a2) was measured in the faulted and folded middle part of the Babadağ Formation. The Babadağ3 section (100 m) (Fig. 4a3) was mea sured in the lowermost part of the formation. The Babadağ1 and Babadağ2 sections were formed by the alternations of pinkgrey, thin (35 cm) -medium (1520 cm) thick bedded (3040 cm), ero sive based, truncated topped, calcilutitecalcarenite units in places. Thinlayered (23 cm), locally slumped, chert bands and lenses are observed at the base of the unit, however they are mostly absent in the upper levels. Moreover, the Babadağ3 sec tion contains thin bedded (25 cm) calcilutite and thin to medium bedded (415 cm) calcarenite alternation with chert bands (35 cm thick, 520 m long) and lenses (510 cm thick, 3050 cm long) ( Fig. 4a; KORE, 2018).
Karadon Sections: The Karadon Sections are located to the NW of Dalaman Town (Fig. 2). Calciturbidite layers are exposed along the road cut to the south of Ortaca town. The Babadağ For mation is normally faulted in the eastern part and covered with alluvium. Within the Karadon neighbourhood, the Marmaris Ophiolite Nappe tectonically overlies the unit, while the Faralya Formation consisting of volcanic rocks and young sediments un conformably overlies the unit in the western part.
Yangı section: This section was measured in Yangı village about 23 km northeast of Köyceğiz (Fig. 2). A 170 m thick cal citurbidite succession was measured. The Yangı section is com posed predominantly of thin (25 cm)mediumthick (1017 cm) bedded, undulating, creamyellowgreyreddish coloured lami nated calcilutite, laminated calcisiltite and finegrained calcareni te (Figs. 4c, 7). Large chert nodules were observed near to the middle of the unit. Unlike the chert observed in other areas, these were found to be irregularly shaped (2030 cm thick, 13 m long). A slump was identified at 110 metres in the section (Fig. 7).
Bozburun hill: Bozburun hill is located on a different nappe slice, about 10 km southwest of the Karadon Section. On the Boz burun hill, calciturbidites of the Babadağ Formation overlie the older Tavas Nappe deposits, and are unconformably overlain by the Faralya Formation. The Bozburun hill was previously studied in detail (GÜL et al., 2013;GÜL, 2015;SARI, 2017). They re ported that Bozburun hill is composed of mainly laminated and thinly (25 cm) undulating, bedded calcilutite at the base, lami nated, thin (48 cm) to medium (1025 cm) bedded calcarenite mainly laminated and thinly (25 cm) undulating, bedded calci lutite alternations with chert layers in the middle, while thin (48 cm) to medium (1025 cm) bedded calcarenites medium (1025 cm) to thickly (30100 cm) bedded calcirudites dominate the up permost part of the succession (Fig. 8).

Whole Rock Mineralogy and Geochemistry
Xray diffractograms reveal the dominance of quartz and calcite in all samples (Fig. 11). Quartz is observed with its prominent peak of 3.34 Å at 26° 2θ; while intense reflection of calcite is de termined at 29° 2θ with 3.03 Å dspacing. Dolomite with very weak intensity at around 31° 2θ and 2.89 Å dspacing is also re cognized in the diffractograms (Figs. 11a, b, c, d). The mineralo gical findings on the bulk compositions are consistent with the microscopic observations. The calciturbidite layers away from the chert lensesbands contain calcite minerals of various sizes. The regional and one line scanmode analysis on these layers by SEMEDS confirms the dominance of Ca, C and O as the major elements. Si amount is negligible. On the other hand, SEMEDS analysis on the sam ple from Bozburun hill, close to the chert bands and lenses, points to the Si enrichment and Ca depletion, indicating the diagenetic replacement of Ca by Si (Fig. 12). Additionally, microcryp tocrystalline calcite and quartz minerals are observed under SEM (Fig. 12 A, C, D). The EDS results are compatible with the mine ral compositions (Fig. 12b). Figure 12e is the image of oneline SEMEDS analysis which illustrates the presence of the elements Si, Ca, Mg and C. Ca enrichment with very low Si content at the beginning of the measured line is associated with microcryp tocrystalline calcite; whereas a higher Si content was determined towards the end of the line with negligible Ca. Very low and al most negligible amounts of Mg are also recorded by EDS scan.
XRF results of the 30 samples are presented in weight per centages (wt.) in Table 1. A high puritychert sample has more than 80% SiO 2 , while calciturbidite samples away from the cher tification or silicification intervals include predominantly >50 % CaO (Table 1). Calciturbidite samples affected by silicification contain 0.230 % SiO 2 . This inverse relationship between Si and Ca is also confirmed by SEMEDS observations (Fig. 13)

Sedimentary features and related depositional environments
The Lycian Nappes units were originally attributed to the south ern part of the northern branch of the Neotethys Ocean located north of the Menderes Massif ( Fig. 1) (ŞENGÖR & YILMAZ, 1981;COLLINS & ROBERTSON, 1998;OKAY, 2001). They mi grated to the south passing over the Menderes Massif units and were emplaced between the Menderes Massif and the Beydağları Autochthone ( Fig. 1; ŞENEL, 1997a;KOZUR et al., 1998;RO BERTSON, 2000;BOZKURT, 2004). The map of the Triassic Cretaceous palaeogeography of the Eastern Mediterranean indi cates that the northern Neotethys Ocean extended from Greece (Pelagonian Zone, Pindos Zone, Cyclades etc.) in the west to Iran in the east including the Taurides (Western Taurides, Lycian Nappes, BeyşehirHoyranHadim Nappes etc.) ( Fig. 1; ROBERT SON & DIXON, 1996;ROBERTSON & MOUNTRAKIS, 2006;VACHARD & MOIX, 2011). The Lycian Nappes represent a tran sition zone between the Greek Hellenides and the CentralEastern Taurides-Turkey (MOIX et al., 2013). The Late Cretaceous period was represented by a compressional regime that led to the frag mentationnappe formation and locally different depositional set tings, such as carbonate platform, continental slope, and deeper marine environments in the Neotethyan Ocean (ROBERTSON & DIXON, 1996;ROBERTSON & MOUNTRAKIS, 2006;VACHARD & MOIX, 2011).
The CenomanianConiacian rudist bearing limestones and the CenomanianCampanian micritic limestone are unconforma bly overlain by the Campanian? -Maastrichtian units of breccia, conglomerates, carbonated sandstones (calciturbidites?) and pe   (SOLAK et al., 2015). Similar age data was reported for the upper part of the Babadağ Formation in the Boz burun hill area (SARI, 2017, and references therein). Similar planktonic foraminiferal content was also observed in the Babadağ Sections, the Karadon Sections and the Yangı Section. However, there is no detailed palaeontological analysis of the fos sil content. The northern Neotethyan Ocean covered large areas of the northern part of the Menderes Massif (ŞENGÖR & YILMAZ, 1981). This ocean hosted important limestone, calci turbidite deposits, rudist reefs, and ophiolites (ŞENGÖR & YILMAZ, 1981). Dependent on compressional regime during the Late Cretaceous, nappe slices of this ocean were transported to the south and formed the Lycian Nappes, some slices were trans ported to the north and formed the Bornova Flysch Zone (ŞENGÖR & YILMAZ, 1981).
Upper Cretaceous calciturbidite deposits with rudist frag ments and planktonic foraminifera were reported from the Ana masAkseki Autochthone, the Antalya Nappes and the Alanya Nappes of the Southern branch of the Neotethys Ocean . In the southern part of the central Taurides, within the upper levels of the Geyikdağı tectonic unit, chert, brecciated sandy, micritic limestone alternations (Campanian) and then dark red coloured pelagic limestone and slumped hemipelagic lime stone (Upper Campanian) of the Cehennemdere Formation were observed by KOÇ et al. (2016).
The existence of similar units was also reported from west of the study area. CLIFT & ROBERTSON (1990) reported that the Argolis Peninsula in southern Greece contains Upper Creta ceous pelagic limestones, calciturbidites, limestoneconglomera tes and slumped units in the middle of the Hellenides. SKOURT SISCORONEOU et al. (1995) (SMF 3,4,5,6,8) with chert lenses in vary ing ratios. They were predominantly deposited on the slope (FZ 4) to deep sea (FZ1) environment. The highest percentage of the calcilutite (SMF 3) was determined in the Yangı section that pos sibly shows the deepest depositional environment of the Babadağ Formation. Calcilutitecalcisiltitecalcarenite alternations with variable ratio in other sections indicate the impacts of local fac tors (sediment input, feeder mechanisms from the shelf part of the platform) in different parts of the platform. Planktonic fora miniferabearing calcilutite requires the lowest sediment input and deposition from suspension, sandgravel size fragments de rived from the shelf margin led to the formation of calcarenite and calcirudite. The highest proportion of calcirudite at Bozbu run hill may be linked with the closeness of the depositional en vironment to rudist buildups along the shelf margin.
The findings of the XRD, XRF, SEMEDS and petrographic studies indicate the presence of calcite and quartz minerals in the samples. ROBERTSON & DIXON (1996), ROBERTSON & MOUNTRAKIS (2006), VACHARD & MOIX (2011) and seve ral other previous studies suggested that the calciturbidites were deposited on the carbonate platform, continental slope and deep sea environment. Detritus from the shelf included mainly calcite shelled organic buildups on the shelf margin. Thus, the sources of the calciturbidite were similar in chemical composition (domi nantly CaCO 3 ), with varying size (clay to gravel). The inverse relationship between Si and Ca is possibly due to silicification processes during diagenesis (Figs. 12, 13; Table 1). The presence of calcite in the mineral compositions and Ca in the bulk chemi cal composition of the chert bands and lenses indicates that the silicification process was not completed. Similarly, silica in cal citurbidites reveals incomplete silicification processes. Based on petrographic observations, GÜL (2015) suggested that the quartz replacement with calcite happens without any size change. The size of the calcite minerals influences the growth of chert (Fig.  9). In figure 9a, the replacement of claysilt sized calcite by equal size quartz led to forming, porcelainous, microcrystalline chert; while in figure 9b smallmedium sized quartz substitutes calcite.
Moreover, rhombohedral dolomite crystals were detected in Fi gure 9a. Similar observations were also reported by GÜL (2015) who determined diagenetic effects such as dolomitization, sub stitutionreplacement, and silicification in the units based on pe trographic studies.

Factors controlling sedimentation
The main controlling factors on the deepsea sediments includ ing calciturbidites are tectonic activity, sealevel fluctuation, ba sin morphologygeometry, sediment input, water chemistry, cur rents, continental slope heightgradient, organic activities, climate changes, etc. (EVERTS, 1991;READING, 1991;REI JMER et al., 1991;HAUGHTON, 1994;RICHARDS et al., 1998;HAUGHTON, 2000;ESCHARD & JOSEPH, 2002;LOMAS & JOSEPH, 2004;DEWEVER et al., 2007;REIJMER et al., 2008REIJMER et al., , 2012GARCIACARO et al., 2011;GÜL et al., 2012;RUBERT et al., 2012;HAIRABIAN et al., 2015;REIJMER et al., 2015aREIJMER et al., , 2015b. These factors may vary from region to region. For exam ple; the main tectonic activities and related sea floor morphology control the sediment input and sediment quantity and thus gra vityflow deposits in the Southern Provence Basin (SE France) (REIJMER et al., 1991;SAVARY et al., 2004;REIJMER et al., 2015b). Moreover, a few cm thick calciturbidite layers at the base of the Lower Cretaceous cherty limestones in Slovakia in the middle of the Western Carpathians are associated with small scale seismic activity (MICHALIK et al., 2012). Additionally, linear source formation, asymmetric geometry of base topogra phy and facies differences of the Jurassic units in the Eastern Al pineSwiss were attributed to a boundary fault (EBERLI, 1987). The calciturbiditic Pliensbachian (Lower Jurassic)Upper Creta ceous series of the Lycian Nappes were interpreted as reflecting the passive continental margin period after the synrift period (MOIX et al., 2013). Sea level changes were responsible for ex cess sediment input and calciturbidite formation in the Bahamas during the Pleistocene (REIJMER et al., 2008(REIJMER et al., , 2015a. Variations in the turbidity flow regime led to the development of lithologi cally different units such as mudstonewackestone, sorted or packed biomicritepackstone etc. (DEWEVER et al., 2007).
Several factors account for the deposition of the calciturbidi tes in the study area. Notable factors among these are discussed below.

Tectonism and depositional basin geometry
Tectonism controls the morphologygeometry of the sea floor, the amount of sediment supply, palaeocurrent direction, entry point of the sediments, sediment quantity, internal structure of the sediments including slumps and flow characteristics (energy, velocity etc. thus facies type) (BOUMA, 2004;GÜL et al., 2012;BAUMGARTNER, 2013).
The depositional environments of the Babadağ Formation were interpreted as continental slope, and related platform mar ginshelf margin and deep water (ŞENEL et al., 1994;ŞENEL, 1997aŞENEL, , 1997bŞENEL, , 1997cCOLLINS & ROBERTSON, 1998, 1999GÜL, 2015;SOYCAN et al., 2015;SARI, 2017;Fig. 10). Seismic activities and/or sea level fluctuation triggered the destabilisation of sediments on the shelfplatform margin areas before the nappe formation and led to the formation of coarsegrain sediments (cal cirudite and calcarenite) on the continental slope and toe of slope (GÜL et al., 2012(GÜL et al., , 2013GÜL, 2015). Alternatively, tectonically quiet periods were represented by calcilutite layers. Moreover, an internal deformation (undulating bedding, slumps) of the sedi ments characterized the continental slope environment. Calcite filled joints, folding, faulting, and nappe formation -fragmenta tion of the original carbonate platform was also related to tectonic activities during and after the Lycian Nappe migration.

Sea level fluctuations and sea depth
Sea level fluctuation and related sea depth control the transporta tion and deposition of deepsea sediments (BOGGS, 1987;READING, 1991;GÜRBÜZ, 1999;GERVAIS et al., 2004;REI JMER et al., 2008;GÜL et al., 2011GÜL et al., , 2012GÜL et al., , 2015SOYCAN et al., 2009SOYCAN et al., , 2011SOYCAN et al., , 2015. Sea level fluctuations cause destabilization of sediment on the shelf edge and on the continental slope (GÜR BÜZ, 1999;GERVAIS et al., 2004). GÜL et al. (2012) proposed that large scaleregional and/or possibly global sea level changes control depocenter development and largescale sediment differe ntiation, moreover smallscale variation of sea level was possibly due to local tectonic activities that led to the facies variations of the Babadağ Formation. The Standard Micro Facies (SMF) changes and related Facies Zone (FZ) changes indicate that the four main depositional environments were 'slope, toe of slope, deep shelf, deep sea water basin -FZ 4321' (Fig. 10). Sealevel fluctuations due to regional uplift and subsidence of the basin may be responsible for these environmental transitions. The falling stage and/or tectonically active period in association with excess sediment input caused the coarsegrained calciruditecalcarenite level in the Babadağ section to represent deposition on slope slope front environments (FZ34; Fig. 10). Subsequent plank tonic foraminifera bearing calcilutite levels were interpreted as a product of the highstand period, low energy level, and quiet deep sea environment (FZ12; Fig. 10) conditions.

Sediment input and sediment type (nature of the source area)
Sediment entry, sediment type and sediment quantity have af fected the deepsea sediment characteristics, including geometry and facies differentiation, such as single or multiplesourced sub marine fans, coarse grainedsand rich turbidite systems and a fine grainedmud rich turbidite system depending on depocenter (RICHARDS et al., 1998;GÜRBÜZ, 1999;BOUMA, 2004;GERVAIS et al., 2004;GARCIACARO et al., 2011;GÜL et al., 2011GÜL et al., , 2012GÜL et al., , 2015. Calcarenitecalcirudite levels of the Babadağ Formation were formed as a result of the sediments derived from the shelf includ ing rudist buildups. The fragments of these initially accumulated on the shelf margin and tectonic activity/sea level lowering trig gered destabilization and downslope movement. The calcirudite calcarenite (unsorted biomicritesparite or floatstonerudstone) deposited on the slope and toe of slope (FZ 4, 3) depended on ex cess sediment input and a short transportation distance. Generally, 35 cm thick calcarenite and calcirudite levels were defined in the Babadağ, Karadon and Yangı sections, while field observations during this study and GÜL et al. (2013) and GÜL (2015) docu mented 30 cm2 m thick calcirudite levels in the Bozburun hill area, representing excess sediment input and/or close proximity to the source area. The ophiolite belts in the Eastern Mediterra nean including the Neotethyan Oceans evolved from the Jurassic to the Cretaceous (ŞENGÖR & YILMAZ, 1981;ŞENGÖR et al., 1984;ROBERTSON, 2002;ALDANMAZ et al., 2009 Silicification during and after lithification led to the forma tion of chert nodulebands (GÜL et al., 2013;GÜL, 2015;SARI 2017). GÜL (2015) used petrographic results to explain this pro cess. He reported that chert horizons were mostly observed with the calcarenitecalcirudite level on Bozburun hill. In addition, he also documented that porcelainous microcrystalline quartz formed as a result of the replacement of calcilutite, chalcedony type quartz minerals were developed depending on the substitu tion of large calcite minerals such as rudist fragments. Elemental analysis clearly indicates the replacement between the Si and Ca elements via the inverse proportions of these two elements (KORE & GÜL, 2017;KORE, 2018). Silicification slightly pene trated into the calciturbidites at lower and upper part of the chert bands (GÜL, 2015). Furthermore, lateral continuation of the chert bands and lenses is limited over a short distance. The long est chert bed reported by GÜL (2015) is 35 m in the Bozburun hill area. It is thought that the formation of chert depends on the circulation and amount of silicarich water that penetrated the calciturbidites. Thus the permeability and porosity of the host rock (calciturbidites) were to become important factors control ling the silica rich water circulation. Thus, it is anticipated that more chert formation occurred in the calcarenites and calciru dites as in the Bozburun hill, Babadağ1 section, Babadağ2 sec tion, Karadon1 section, and Karadon2 section (Fig. 4). In addi tion, if the chert beds were deposited synsedimentary and alternated with the calciturbidites, long and more regular chert beds could be traced. However, the irregular and short chert oc currences of the Babadağ Formation suggest that they evolved during diagenesis of the calciturbidite via quartz replacing cal cite. In addition to these, postsedimentary diagenetic activities can also be traced by rhombohedral dolomite formations within the cracks already filled by calcites that cut both calciturbidites and cherts.
This study reveals that an investigation on the distant nappe unit that is mapped under the same name, should supply the in formation about the original depositional environment. Detailed analysis of each nappe slice is useful for determining the local controlling factors on deposition besides the general trend con firmation. Other important issues related to calciturbidite depo sition are that they are generally affected by tectonic activities and the depth of the basin. Local sediment typesizequantity may lead to coarsegrain deposition. Calciturbidites play an ac tive role during diagenesis, and also open pathways for chemi cally active liquids through which they can move easily leading to the formation of chert bands and lenses as observed in the study area.

CONCLUSIONS
This study documents the compositional changes, and discusses the factors controlling the deposition and sedimentological chara cteristics of the calciturbidites of the Babadağ Formation of the Tavas Nappe in Muğla (SW Turkey). With the help of field obser vations and many analytical methods, the following conclusions are drawn: The studied calciturbidites comprise mainly calcilutite -cal cisiltite, and calcarenitecalcirudite in a small amount depending on the environmental conditions. Calcarenite and calcirudite oc currences represent deposition on the slope or toe of slope; how ever, the predominance of calcilutite points to deposition in deep shelf and deep sea environments.
Planktonic foraminiferabearing, micritic calcilutites were deposited in the deep marinedeep shelftoe of slope environ ments. Mostly rudist fragmentbearing, locally slumpedundu lating beddeddeformed calcarenites and to a lesser extent cal cirudites were deposited in the slope environment.
Detailed analysis of each nappe slice belonging to the same nappe unit not only provides general information on the environ ment and lithology, but also indicates local factors including lo cal sediment input etc.
Tectonism and sealevel fluctuations are determined as the main controlling factors on deposition of the Babadağ Formation. Steady, tectonically quiet periods, low sediment input and the ab sence of gravity flows resulted in the deposition of calcilutite micritic sediments. Subsequently, sealevel lowering, tectonically active periods (uplift) and excess sediment input led to the deve lopment of calcarenitecalcirudite levels. Changes of the control ling factors over time triggered the repetition of formation of the finegrained and coarsegrained calciturbidites.
Sediment grain size played an important role during diage netic stages. The coarsegrained calciturbidite supply provided a suitable pathway for Si enrichment water circulation and there fore chert or dolomite formation.
Calcite and quartz were observed as the major mineral com ponents in the samples. Both SEMEDS and XRF analysis show the inverse variation between CaO and SiO 2 due to replacement during diagenesis. Excess silica replacement especially was gene rally observed in calcarenitecalcirudite levels which, in turn, led to formation of the chert bands/lenses. All chert bands con tain a negligible amount of calcite which is due to the incomplete silicification process. Moreover, the Si content of pure calcitur bidite samples either above or below the chert level shows the diffusive characteristics of the Sienriched water.