Yarımburgaz Cave

Yarimburgaz Cave (Turkish: Yarımburgaz Mağarası) is a cave of significant archaeological and paleontological importance, located in eastern Thrace and within Istanbul Province, Turkey.

Location

Yarımburgaz Cave is approximately 20 km (12 mi) west of the city of Istanbul, and about 1.5 km (0.93 mi) north of Lake Küçükçekmece and south of Sazlıdere Dam. It is situated in a locality known today as Altınşehir, within the neighborhood of Güvercintepe in Başakşehir district.

Geology and cave formation

The cave was formed as a result of a subterranean river eroding and dissolving an ancient Eocene limestone formation. It has two entrances, one above the other. The lower entrance is at an altitude of 11.5 m (38 ft) AMSL, and the upper entrance at 7 m (23 ft). The cave opens onto the eastern bank of the Sazlıdere creek, which empties into Lake Küçükçekmece. The entrances face southwards overlooking Sazlıdere Valley. The lower cave is a long meandering tunnel that extends deep into the hillside at a length of 500 m (1,600 ft), and forks into two narrower tunnels around 240 m (790 ft) from the mouth. The upper cave extends only 52 m (171 ft) into the bedrock. The upper cave chamber is 15 m (49 ft) wide and 10 m (33 ft) in height near the entrance. The two chambers are connected internally by a short, sloping passage approximately 25 m (82 ft) from the entrance.

Scientific research

The cave is an important fossil and archaeological site whose deposits span several cultural and geologic periods, and which have been researched by archeologists, paleontologists, geoarchaeologists and biospeleologists. Scientific exploration of the cave began in the mid-19th century, focusing mainly on its geological characteristics and setting. Recognition of the cave's importance for Holocene and Pleistocene prehistory of Turkey came only in the 1960s and after, based on several test pits that explored the Chalcolithic occupation in the cave. Excavation work in the 1980s was both more extensive and systematic. The first campaign was a salvage excavation conducted in 1986 by archaeologists from the University of Istanbul, which tested both cave chambers but focused mainly on the Byzantine, Chalcolithic and Neolithic occupations in the upper cave. An early Paleolithic presence was also recognized, though highly disturbed in the upper cave but apparently intact in the lower cave. The second excavation campaign from 1988 through 1990 was a collaboration between archaeologists from the University of Istanbul and University of California-Berkeley, which focused on the Paleolithic components in the lower cave and complete characterization of the 5 meter deep stratigraphy of the site, funded by the National Geographic Society.

Archaeological sequence and formation processes

During the Byzantine era, a church was carved into the walls of the upper cave, and a monastery was built outside the cave mouth. These alterations resulted in major disturbance to underlying layers containing prehistoric material. In all, the upper cave preserves relatively intact traces of human occupations dating to the Bronze Age, Chalcolithic, Neolithic, and scant disturbed traces of Upper Paleolithic and earlier deposits. Pottery finds from the Chalcolithic and Neolithic ages indicate links between the Balkans and the Aegean and Anatolian cultures via Thrace, and continuous human use of the Upper Cave from about 5500 BC onward.

Below these cultural layers is a stratified sand and gravel deposit that is over 3.0 m thick and does not contain artifacts. This deposit represents a former high sea level (marine transgression) that flooded into the cave mouth; it is a beach sand from the Last Interglacial period,. Paleolithic artifacts occur within the stratigraphically intact sediments under the beach layer in the lower cave, especially in the spacious area near the entrance. Paleontological and archaeological findings indicate revolving use of the cave by early humans and several species of non-human animals, especially cave bears. The faunal assemblages include bones of diverse herbivores and carnivores, marine and freshwater molluscs, microfauna, as well as chipped stone artifacts made from flint, chopper tools and hammerstones from quartzite, as well as manuports. Common large mammal remains include late Middle Pleistocene cave bears (Ursus deningeri), horses (Equus caballus), wild boar (Sus scrofa), fallow deer (Dama dama), roe deer (Capreolus capreolus), giant deer (Megaloceros), wild cattle (Bos/Bison), gazelles (Gazella), wild goats (Capra), and less commonly carnivores such as wolves (Canis), foxes (Vulpes), large cats (Panthera), wildcat (Felis), and hyenas (Crocuta).

The micromammal assemblages from the lower cave provide important chronological and ecological indicators. The evolutionary stage of the steppe lemming, Lagurus transiens/lagurus, indicates a Middle Pleistocene age. Species composition is relatively uniform through the Paleolithic deposit, with several species of Middle Pleistocene bats (Chiroptera), including horseshoe bats (Rhinolophus), mouse-eared bats (Myotis), long-eared bats (Plecotus), and bent-winged bats (Miniopterus)..

Attempts to determine the age of the Paleolithic occupation have met with some mixed results, but the weight of the combined evidence from geostratigraphy (including the site's low elevation and proximity to the sea), ESR dating, and biostratigraphy suggests that alternations in hominin and bear presence in the cave occurred within the later part of the Middle Pleistocene, specifically Marine Isotope Stages 7 or 8 (roughly 250,000 and 180,000 years before present).