PLEISTOCENE AND HOLOCENE SEDIMENTS IN VELA SPILA
CAVE, CROATIA
LJ. PAVICIC*, M. MILEUSNIC** & D. RADIC***
*Institute for Quaternary Paleontology and Geology, Croatian Academy of Science and Arts, Zagreb, Croatia
([email protected])
**Faculty of Mining, Geology and Petroleum Engineering, Zagreb, Croatia
***Cultural Center, Vela Luka, Croatia
Vela Spila cave is situated on the Pinski rat hill near the town Vela Luka on the island of
Korčula, Croatia. It is one of the richest archaeological and paleontological sites in Eastern
Adriatic. Archaeologists have proved the continuity of human occupation of Vela Spila cave
through Early Neolithic untill Early Bronze Age, and periodic human inhabitation through
Upper Palaeolithic and Mesolithic (Čečuk & Radić, 2005).
First sedimentological research was conducted in 2002, when the western profile of main
trench was described and the distinctive tephra layer, dated from 15 ka ago, found (Radić et
al., 2008). Since then the trench has been extended during the archaeological excavations in
2004 and 2006 when deeper Pleistocene sediments were opened. New sedimentological
investigations begun in 2008, in order to gain more information regarding the formation of
sediments, as well as paleoenvironmental and palaeoclimatic conditions during their
deposition. Four stratigraphic profiles of main trench were drawn, and more than 40 samples
were taken for laboratory analyses.
Laboratory investigations are based on detailed sedimentological (grain size analyses;
microscopic analyses), geochemical (major, trace and rare earth element analyses; total
sulphur and carbon determinations; carbonate and organic matter content, pH and electrical
conductivity determinations) and mineralogical analyses (powder XRD analyses of bulk
samples, as well as, XRD analyses of the random and oriented samples of clay fractions < 2
m and cation exchange capacity determinations) of sampled fine grained sediment.
Sedimentological and petrographical analyses of thin sections of carbonate clasts and grain
size and morphometric analyses are performed on the samples of carbonate breccia.
We will present the first results of laboratory analyses from samples taken in eastern profile
A-A' which comprises the whole range of recently opened Pleistocene deposits as well as the
distinctive boundary layer between Palaeolithic and Mesolithic sediments.
Based on these analyses three Pleistocene horizons can be distinguished: a) Lower horizon
represents massive coarse grained beds with very little or no matrix, with subangular to
angular platy or bladed carbonate clasts, mostly remnants from the bedrock disintegration and
ceiling collapses. There is little evidence of human occupation of the cave in this period. b)
Middle horizon consists of thiner, mostly lenticular sandy-silty gravels which show strong
anthropogenic influence (great amount of bones, stone tool fragments, charcoal, high organic
content and less carbonate minerals). Some carboniferous and clay lenses are interpreted as
fire-places. c) Upper horizon is marked mostly by gravely-sandy silts with lower
anthropogenic factor and higher carbonate component. It comprises the boundary layer
between Pleistocene and Holocene (Palaeolithic and Mesolithic) which is distinctive layer of
matrix supported, very poorly sorted, gravely silt with large carbonate blocks implanted into
finer sediments deforming the layer beneath (visible deformation structures). The uppermost
analized layer belongs to Mesolithic (Holocene), proved by radiometric C14 dating as well as
by fossil remains (fish bones, marine fauna shells, small mammal bones) which reflects
changing environment (uprising sea-le˜(l and changing climate conditions).
Investigations of Vela Spila cave sediments are still in progress and represent good
collaboration between archaeologists and geologists.
Čečuk, B. & Radić, D. (2005): Vela spila. Višeslojno pretpovijesno nalazište Vela Luka – otok Korčula.
Centar za kulturu „Vela Luka“. Vela Luka. p. 300.
Radić, D., Lugović, B. & Marjanac, Lj. (2008): Napuljski žuti tuf (NYT) iz pleistocenskih naslaga u Veloj spili
na Korčuli: dragocjeni marker prijelaza iz paleolitika u mezolitik. Opvsc. archeol., 31, 7-26.
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pleistocene and holocene sediments in vela spila cave, croatia