A Revised Chronological and Palaeoenvironmental Framework for the Kastritsa Rockshelter, Northwest Greece

Article excerpt

Kastritsa, excavated by E. Higgs in 1966 and 1967, is a small cave situated in the side of a limestone hill on the shore of Lake Pamvotis, in the Ioannina basin, northwest Greece (FIGURE 1) (Higgs et al. 1967). Archaeological finds included lithic and organic artefacts exhibiting variability through time and a diverse faunal assemblage dominated by deer (Bailey et al. 1983). Sturdy et al. (1997: 603-4) have shown the site's advantageous location in a seasonally varying biotope whose resources would have been more abundant during summer. Amongst the Upper Palaeolithic sites of southeast Europe, Kastritsa stands out because of its abundance of habitation features (various hearth types, post-holes and chipping floors) and refittable lithics (Higgs 1968; Galanidou 1997b; 1999; in press). From a palaeoclimatic point of view, Kastritsa's notoriety lies in the presence of a series of beach deposits in the lower part of the sequence, thought to represent higher lake levels during the `Last Glacial Maximum' (LGM) (Higgs et al. 1967: 21; Bailey et al. 1983: 29). The evidence for high LGM lake levels has been in conflict with palaeoecological results suggesting increased aridity during this interval (Bottema 1974) and much discussion has permeated the literature in order to account for the apparent paradox (e.g. Bailey et al. 1983: 29; Bailey et al. 1986: 105; King & Bailey 1985: 280-81; Prentice et al. 1992; Tzedakis 1994: 420; Frogley 1997: 161-4). Here we present new AMS radiocarbon determinations which provide a different chronological framework for the sequence, and reconsider the local palaeoenvironmental conditions through new pollen and ostracod evidence from an adjacent sediment core from Lake Pamvotis.

[Figure 1 ILLUSTRATION OMITTED]

Stratigraphy

Kastritsa's stratigraphy is the result of a complex sedimentation history consisting of events of human occupation and deposition, rockfalls, fluctuating lake levels, and other sedimentation episodes. During excavations, 32 layers were identified and numbered Y1-Y32 (TABLE 1). These units were subsequently grouped into five strata, 1, 3, 5, 7 and 9 to `allow pooling of samples for analysis' (Bailey et al. 1983: 25-6). Stratigraphically, the sequence was divided into three major depositional units (Bailey et al. 1983: 25-6). The upper unit (layers Y1-Y15) contained terrestrial deposits, rich in finds and habitation features. Numerous episodes of rockfalls have left their mark upon this upper series. The finds recovered were most densely congregated at the present-day entrance to the cave. At the lower part of this unit a beach deposit was recorded in Y14a (Bailey et al. 1983: 28; Galanidou 1997a: figure 6.21). The middle unit (layers Y16-Y26) was characterized mainly by beach deposits consisting of water-worn pebbles and fine grained lake sediments. Artefacts and hearths were present in this part of the sequence, the number of artefacts dropping gradually with increasing depth. The lowest unit (layers Y27-Y32) lay in certain areas upon bedrock and consisted of waterlogged deposits having localized lenses of pebbles and freshwater mollusc shells. It was devoid of any anthropogenic material, possibly representing a period during which Kastritsa was under water. In what follows, our reference to the sequence will relate to layers Y1-Y26, in which human presence has been attested.

TABLE 1. Stratigraphical scheme of the Kastritsa sequence and associated radiocarbon dates.

                           units   strata   layer

         humus/topsoil                       Y1
                                             Y2
                                             Y3
                                             Y4
          silty clays,                       Y5
        stone fragments,                     Y6
           extensive         1               Y7
         anthropogenic               3       Y11
            deposits                         Y12
                                             Y13
beach                                5       Y14
                                             Y15
beach                                        Y16
beach                                        Y17
beach                                7       Y18
                                             Y19
            beaches/                         Y20
beach    anthropogenic       2               Y21
            deposits                         Y22
beach                                        Y23
                                             Y24
beach                                        Y25
                                             Y26
                                     9       Y27
                                             Y28
         lake deposits       3               Y29
                                             Y30
                                             Y31
                                             Y32

layer                  old dates                       new dates

 Y1
 Y2               13,400 [+ or -] 210
 Y3
 Y4
 Y5
 Y6
 Y7
 Y11
 Y12                                              20,000 [+ or -] 80
 Y13                                              21,350 [+ or -] 80
 Y14
 Y15              19,900 [+ or -] 370
 Y16
 Y17
 Y18
 Y19
 Y20              20,800 [+ or -] 810
 Y21    21,800 [+ or -] 470/20,200 [+ or -] 480
 Y22
 Y23
 Y24                                             23,880 [+ or -] 100
 Y25
 Y26
 Y27
 Y28
 Y29
 Y30
 Y31
 Y32

Dating

The 1960s radiocarbon determinations indicated the site's overall temporal succession (Higgs et al. …