geosciences Article SARchaeology—Detecting Palaeochannels Based on High Resolution Radar Data and Their Impact of Changes in the Settlement Pattern in Cilicia (Turkey) Susanne Rutishauser 1,*, Stefan Erasmi 2, Ralph Rosenbauer 1 and Ralf Buchbach 2 ID 1 Institut für Archäologische Wissenschaften, Universität Bern, Abt. Vorderasiatische Archäologie, Länggass-Strasse 10, 3012 Bern, Switzerland; [email protected] 2 Geographisches Institut, Georg-August-Universität Göttingen, Abt. Kartographie, GIS & Fernerkundung, Goldschmidtstr. 5, 37077 Göttingen, Germany; [email protected] (S.E.); [email protected] (R.B.) * Correspondence: [email protected]; Tel.: +41-31-6318992 Received: 22 July 2017; Accepted: 16 October 2017; Published: 24 October 2017 Abstract: The fertile alluvial plain of Cilicia is bordered by the Taurus and Amanus mountain ranges to the west, north and east and the Mediterranean Sea to the south. Since the Neolithic Period, Plain Cilicia was an important interface between Anatolia and the Levant. The alluvial plain is dominated by three rivers: Tarsus, Seyhan and Ceyhan. The avulsion history of the lower course of the rivers Seyhan and Ceyhan during the Holocene remains an unresolved issue. The knowledge about how former river courses have changed is essential for the identification of ancient toponyms with archaeological sites. The analysis of silted up riverbeds based on high-resolution digital elevation models (TanDEM-X) and historic satellite imagery (CORONA) in this paper provide the first indications for the reconstruction of former river channels. Further evidence is given by the evaluation of the settlement patterns from 3rd to 1st millennium BC. Keywords: Cilicia; Seyhan; Ceyhan; Puruna; avulsion; TanDEM-X; CORONA; remote sensing; archaeology 1. Introduction The changes of river courses, which have had a strong influence on the development of sites and is important for the localization of sites has not been investigated in Cilicia in detail so far. Only the development of river deltas and the changes of the river Tarsus have been studied in detail [1–4]. For the identification of toponyms known from written sources with archaeological sites, precise knowledge about the changes of river courses is essential. The aim of this paper is a first look at the development of the Seyhan and Ceyhan rivers during the late Holocene. Due to the lack of available coring data, this will be done by the analysis of remote sensing data in combination with a study of changes of the settlement cluster in Plain Cilicia. In southern Mesopotamia, studies about ancient watercourses on which all communication moved and along which all settlement ranged itself were undertaken already in the 1960s and 1970s on the basis of archaeological data and remote sensing data (LANDSAT) [5]. Since then, much more data has become available e.g., CORONA and TanDEM-X. In this study, these archives will be analyzed for the region of Plain Cilicia. Plain Cilicia (gr. Kilikia Pedias, lat. Cilicia Campestris) covers an area of approximately 8000 km2 in the northeastern corner of the Mediterranean Sea. Like almost no other landscape in Asia Minor, this plain is defined by strong topographic contrasts: a large fertile plain surrounded by steep mountain ranges. The Middle Taurus Range (turk. Orta Toroslar), which exceeds 3700 m in elevation, borders the landscape to the west and north. In the east, the settlement cluster is confined by the Amanos (turk. Nur Da˘gları)that separates Plain Cilicia from inner Syria and reaches elevations of up to 2200 m. The Gulf of Iskenderun and the Gulf of Mersin form its southern boundary (Figure1). Geosciences 2017, 7, 109; doi:10.3390/geosciences7040109 www.mdpi.com/journal/geosciences Geosciences 2017, 7, 109 2 of 20 elevations of up to 2200 m. The Gulf of Iskenderun and the Gulf of Mersin form its southern Geosciencesboundary2017 (Figure, 7, 109 1). 2 of 20 Natural passes through the mountains still form the main routes of access to the lowlands. The “CilicianNatural Gates” passes (turk. through Gülek the Boğ mountainsazı) at an elevation still form of the 1290 main m routesconnect of Anatolia access to with the lowlands. the plain Theand “Cilicianserve as the Gates” main (turk. passageway Gülek Bo˘gazı)at for railroad an tracks elevation and ofmajor 1290 vehicular m connect roads Anatolia up until with this the day. plain In and the servewesternmost as the main part passagewayof Plain Cilicia, for forming railroad the tracks transition and major to Rough vehicular Cilicia, roads the up Göksu until Valley this day. stretches In the westernmostnorth–south from part ofthe Plain Konya Cilicia, Plain forming to coastal thetransition Silifke and to Roughrepresented Cilicia, an the important Göksu Valley connection stretches to north–southAnatolia in antiquity from the [6] Konya (p. 88). Plain The to coastalBahçe Pass Silifke (“Amanian and represented Gates”) anin importantthe East leads connection over the to AnatoliaAmanus inRange antiquity and [serves6] (p. 88).as a The passage Bahçe between Pass (“Amanian Cilicia and Gates”) the Islahiye in the East Plain. leads Further over the south, Amanus the RangeOrontes and Valley serves can as abe passage reached between over Ciliciathe Belen and thePass Islahiye (“Syrian Plain. Gates”). Further Access south, from the Orontes the north Valley is canfacilitated be reached by several over the tributary Belen Passvalleys (“Syrian of theGates”). Seyhan and Access Ceyhan from rivers. the north Late is Bronze facilitated and by Iron several Age tributaryrock reliefs valleys as well of the as Seyhaninscriptions and Ceyhan like Hanyeri, rivers. Lateİmamkulu, Bronze andTaşç Ironı and Age Frakt rockın reliefs[7], mark as well their as inscriptionssignificance likein antiquity. Hanyeri, Imamkulu,˙The plain itself Ta¸sçıand is divided Fraktın into [7], marka western their significance(Çukurova) inand antiquity. an eastern The plain(Yukar itselfıova) is settlement divided into cluster a western by a (Çukurova)natural border and fo anrmed eastern by (Yukarıova)the foothills settlementof the Middle cluster Taurus by a naturalRange and border the formedMisis Mountains. by the foothills The approximately of the Middle 760 Taurus m high Range Misis and Mountains the Misis [8] Mountains. (pp. 305–307) The approximatelyextend northwards 760 m from high the Misis western Mountains end of [ 8the] (pp. Gulf 305–307) of Iskenderun extend northwards(Figure 1). The from average the western height end of ofthe the Çukurova Gulf of Iskenderun is about 15 (Figurem above1). sea The level. average The heightheight of of the the Çukurova Yukarıova is varies about from 15 m 20–100 above seam above level. Thesea level. height of the Yukarıova varies from 20–100 m above sea level. Figure 1. Map of Plain Cilicia and its neighboring regions. Topographic data based on SRTM (Shuttle RadarFigure Topographic1. Map of Plain Mission, Cilicia U.S. andGeological its neighboring Survey, regi 3ons. Arc SecondTopographic scene) data [9] ©based Susanne on SRTM Rutishauser. (Shuttle Radar Topographic Mission, U.S. Geological Survey, 3 Arc Second scene) [9] © Susanne Rutishauser. Three main rivers, originating in the Taurus Mountains, cross the lowlands and discharge into the MediterraneanThree main rivers, Sea: Berdanoriginating or Tarsus in the Çayı Taurus (gr. Mountains,Kydnos), Seyhan cross (hitt.the lowlandsŠamri/Sapara and ,discharge gr. Saros) into and Ceyhanthe Mediterranean (hitt. Puruna Sea:, gr. BerdanPyramos or Tarsus)[10] (p. Çay 6).ı (gr. These Kydnos rivers), Seyhan form the (hitt. deltaic Šamri complex/Sapara, thatgr. Saros occupies) and theCeyhan Adana (hitt. Basin Puruna (Figure, gr.2 Pyramos). The Adana) [10] (p. Basin 6). These represents rivers the form onshore the deltaic extension complex of the that marine occupies Cilicia the Basin [11] (p. 123). The 6000 m thick sedimentary succession of the Adana Basin is spanning Miocene Geosciences 2017, 7, 109 3 of 20 Geosciences 2017, 7, 109 3 of 20 Adana Basin (Figure 2). The Adana Basin represents the onshore extension of the marine Cilicia Basin [11] (p. 123). The 6000 m thick sedimentary succession of the Adana Basin is spanning Miocene to Recent [[12]12] (p.(p. 190) and isis builtbuilt byby alluvialalluvial variablevariable grainsizegrainsize deposits [[13]13] (p.(p. 135). All rivers are braided in their upper reaches with channel gradients ranging from 1:40 to 1:400, while the channel gradients decrease to >1:2000 in the lower 35–110 km of their courses, causing them to meander [[14]14] (p. 57). The major tributaries of the 560 km long Seyhan are thethe Göksu,Göksu, Zamantı,Zamantı, ÇakıtÇakıt and KörkünKörkün Rivers [[15]15] (p. 647). Prior to construction of the first first dam in 1954 the Seyhan River Delta expanded its area onon averageaverage byby 2.8 2.8 ha ha per per year year [16 [16]] (p. (p. 64). 64). The The dam dam greatly greatly reduced reduced sedimentation sedimentation in the in deltathe delta [17] (p.[17] 5). (p. The 5). 510The km510 longkm long Ceyhan Ceyhan River River drains drains today today into theinto Gulf the ofGulf Iskenderun of Iskenderun and formed and formed a more a thanmore 100than km 1002 large km2 riverlarge delta. river Paleoenvironmentaldelta. Paleoenvironmental studies studies of the Iskenderunof the Iskenderun Bay show Bay a show muddy a sedimentation,muddy sedimentation, which coincides which coincides with a major with a delta major progradation delta progradation of the Ceyhan of the Ceyhan around around 2140 BP 2140 [18] (p.BP [18] 20). (p. Therefore, 20). Therefore, a drainage a drainage into the into Mediterranean the Mediterranean Sea atSea Kap at Kap Karata¸sduring Karataş during the the Iron Iron Age Age is generallyis generally accepted accepted [18 [18]] (p. (p. 20). 20). Figure 2. Morphological and simplified tectonic map of the region with the locations of major Neogene Figure 2. Morphological and simplified tectonic map of the region with the locations of major basins and the main fault zones (FZ) (after [19] Figure1), © Susanne Rutishauser.