SUMMARY: We review extensively the evidence and arguments bearing on the nature of Palaeotethys in relation to the age of formation, location and multiplicity of Neotethyan strands and their fate. We conclude that Palaeotethys did not die early but was only finally subducted northwards in the Tertiary along the Vardar-Intra Pontide-East Anatolian suture. Neotethyan strands must have opened into it at all times. The Adriatic promontory remained attached to Africa but rotated anti-clockwise in the mid-Tertiary. The Ponfldes are considered to be Eurasian and the Cimmerides are viewed as a 'collage terrain' formed along an oblique-convergence margin. The south Aegean, Greek and Turkish microcontinental blocks were rifted-off Gondwana in the Triassic but formation of braided Neotethyan oceanic crustal strands was essentially confined to mid-Jurassic in the Hellenides and to the Cretaceous in Turkey.We propose a new model of ophiolite genesis by asymmetrical spreading-ridge collapse in an attempt to explain both arc-like ophiolite chemistry prior to major volcanic arc edifice construction, and the synchroneity of sub-ophiolite metamorphic sole formation with Atlantic opening phases.Jurassic dispersal of Hellenide blocks had little effect in the unexpanded Turkish mosaic, but northwards Cretaceous opening of Tauride Neotethyan strands caused oblique collision deformation in the Pelagonian zone and unresolvable complexity in the Aegean. Late Cretaceous and Tertiary arc-volcanism was related in part to continuing Palaeotethyan subduction, and in part to Neotethyan destruction initiated after ridgecollapse. Diachronous collisions ensued from the Late Cretaceous onwards but significant oceanic tracts must have persisted at least to Mid-Tertiary to satisfy Africa-Eurasia separation constraints determined from Atlantic anomaly fitting. Our favoured plate evolutionary model is presented in 7 sketch-maps.

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Obsidian was not necessarily the earliest object of trade, but it certainly seems to be the first for which material evidence remains. It has been reported from nearly every Early Neolithic settlement in the Near East, although many of these sites are distant from the natural sources.In our first paper (Cann and Renfrew 1964), we outlined a method for the characterization, by trace-element analysis, of obsidian artifacts from archaeological contexts. This allowed the determination of the natural sources from which the material derived. In that paper, however, only the west Mediterranean region was considered in sufficient detail to give definitive results. The obsidian trade in the Aegean has subsequently been studied in detail also (Renfrew, Cann and Dixon 1965).In the present paper, the obsidian trade in the Near East is examined. This topic is particularly important since obsidian seems to be the most promising approach towards understanding the extent to which the different Early Neolithic cultural and ecological regions were in contact. It should help to suggest how the early spread in the knowledge and use of animal and plant domesticates took place in the Near East.

Obsidian to the Greeks was no more than a semi-precious stone, black and shiny, suitable for mirrors or exotic ornaments. But to their predecessors in the Aegean through five millenia it was an important raw material for the manufacture of tools and weapons. Sharper and more abundant than flint, more easily worked and cheaper than copper, it was not displaced entirely even by the use of bronze, which was always an expensive material, there being no source of tin in the Aegean. Only when knowledge of iron-working was brought to the Aegean coasts did obsidian fall from its position as an important raw material to that of a curiosity.Huge quantities of obsidian are to be found lying about the surface of most prehistoric sites in south Greece—any farmer or shepherd will tell of the ‘little razors’ to be found on his land. But its occurrence in nature is very unusual since it is found exclusively in regions of recent volcanic activity, and then only when certain conditions exist, such as a high silica content in the lava of the volcano. Every single piece found in mainland Greece had to be imported from overseas, a process implying competent geological knowledge, skill in sailing and navigation, and perhaps social organization, to a considerable degree. It is the earliest trade in the world for which we have concrete evidence.

The paper describes preliminary results from the 120sqkm Volvi mafic complex within the Greek Serbo-Macedonian Massif. We conclude from published information and isotopic ages that the central and eastern part of the Massif (basement and Triassic/Jurassic cover) were affected by an amphibolite-facies regional metamorphic and deformational event in the Late Jurassic-Early Cretaceous. Delayed uplift from this same event may explain Tertiary ages from Kerdilion migmatites. The Volvi complex may thus be A: pre-Mesozoic 'basement', or B: an in situ Mesozoic rift complex or C: a Mesozoic collisional suture remnant. Field, microprobe and XRF data appear to fit model B best. Though deformed, the complex has recognisable 100% sheeted-dyke tracts and substantial areas of undeformed gabbro at lower structural levels. Deformation began before the end of magmatic activity: late sheets of pegmatic gabbro cut deformed dykes; late dykes cut sheared gabbro. Assemblages are of high-grade amphibolite facies and give garnet-hornblende temperatures of 750~ significantly higher than inferred for staurolite-garnet schists outside the complex. Geochemically, the basaltic rocks show LIL enrichment and are intermediate between 'alkalic' and 'above-subduction-zone' in character. The complex may relate to Mesozoic rift-basins identified in E. Serbia, but is not thought to be a Palaeotethyan remnant.

Field evidence from north-south transects tests three tectonic models for Tethys in Western Turkey for when a Late Palaeozoic ocean was closing and an Early Mesozoic ocean opening. In Model 1, a Palaeozoic ocean subducted southwards, rifting continental fragments from Gondwana and opening a Triassic Neo-Tethys to the south. Closure and collision occurred by latest Triassic time. In Model 2, a wide Palaeozoic Tethys subducted northwards with an active Eurasian margin and a passive Gondwana margin. The northern Gondwana margin rifted in the Triassic; fragments either remained nearby (Taurides) or drifted northwards (e.g. Karakaya) attached to a north-subducting plate. New oceanic crust replaced Palaeo-Tethys with Neotethys and back-arc marginal basins opened along the south Eurasian margin (e.g. Küre). In Model 3, a Palaeozoic ocean also subducted northwards opening wide marginal basins. A wide Southern Neotethys opened along the Gondwana margin. Rifted Eurasian (Anatolides) and Gondwana (Taurides) fragments collided in mid-Tethys by latest Triassic time. Field evidence from the Pontides supports north-dipping subduction models (Model 2 or 3 above). Key features are a south-vergent, HP-LT accretionary prism, magmatic arc and back-arc basin system bordering the Eurasian margin. Also, evidence from the Tauride Mountains favours Model 2 over Model 3. Critically, the Anatolides and Taurides appear to have a common history and were unlikely to have been located on opposite sides of Tethys, as in Model 3.

The very early development and extent of the obsidian trade in the Near East is being increasingly documented by the discovery and excavation of Early Neolithic sites throughout the area. Since the publication of our last paper (Renfrew, Cann and Dixon, 1966), obsidians from five aceramic Neolithic sites have been analysed, and the natural source of the material determined in each case. All the results fall into the framework of groups already established. In addition, one new obsidian source has been discovered.This confirmation of the characterizations hitherto achieved is satisfactory, but perhaps more important is the new evidence for the reconstruction of the pattern of the trade or traffic in obsidian in Early Neolithic times. Regularities in this pattern are becoming apparent, which allow a greater insight into the trading mechanisms involved.In this paper, written by Colin Renfrew on the basis of analyses and group divisions by J. E. Dixon and J. R. Cann, new information concerning the Anatolian sources is first considered, and new results for the Early Neolithic and later obsidians discussed. In the last section, an attempt is made at the more precise definition of the obsidian trading pattern in the 7th and 6th millennia B.C. on the basis of a more detailed analysis of the prehistoric trade statistics.