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This study integrates provenance and statistical data, along with published sedimentological results, applied on the Lower Oligocene submarine‐fan deposits in Pindos foreland basin. Twelve outcrops were analysed using conglomerate clast composition, petrographic and statistical analysis and this integration suggests that the studied deposits were sourced by the Pindos Orogen. Conglomerate clast composition analysis suggests that the studied deposits contain mainly limestone clasts, followed by sandstone and chert clasts. This conclusion is further supported by the petrographic and cathodoluminescence analyses that have been conducted on the conglomerate matrix and, additionally, suggest the influence of a low‐grade metamorphic source. Potential source rock candidates in the Pindos Orogen that provided the detritus in the succession are represented by the Mesozoic carbonates (limestone and chert), the Cenozoic transitional (mixed carbonate and siliciclastic) and the Cenozoic clastic submarine‐fan deposits (sandstone). The rock units of Pelagonian zone likely represent the low‐grade metamorphic source rock. The principal component and cluster analysis of clast lithologies suggest the existence of three compositional clusters, with the first one being controlled by black chert clasts, the second one by sandstone clasts and the third one by limestone and red chert clasts. The upward increase of chert and lithic fragment abundances is ascribed to the progressive unroofing of the Pindos orogenic source regions. This study utilizes the Pindos foreland basin as an example to unravel the contribution of orogenic processes on sedimentary provenance of the adjacent pro‐foreland basins. Furthermore, this study highlights the advantage of implementing a multi‐faceted approach, including statistical treatment in sedimentary provenance. [ABSTRACT FROM AUTHOR]

Silcrete and chert were used for the manufacture of stone tools in early prehistoric (Middle / Late Palaeolithic and Mesolithic) times in Central Evia island. We have undertaken an analysis of visual characteristics of prehistoric artifacts and the potential source rocks exposed in the area to provide evidence of use of locally available raw material. Field geological surveys indicate that silcrete, chert nodules in limestones, and varicolored cherts within siliceous mudstones and sandstones in the area were potential raw materials for prehistoric knappers. Geological mapping and detailed studies of the mineralogy, texture and geochemistry of critical rock types demonstrate extensive use of different silcrete facies associated with weathered ultramafic ophiolitic rocks and chert nodules occurring within Upper Cretaceous limestones. SEM, XRF, XRD and ICP-MS analytical methods were employed. The hard, massive, buff reddish-brown variety of silcrete triggered the main interest of prehistoric knappers. Provenancing of lithic tools made of silcrete is facilitated by the presence of disseminated grains of relictic chromite/spinel and serpentine, and the high Cr, Ni, Fe, Mg, Co, V contents. Chert nodules are depleted in almost all the major, minor and REE elements, except for silica and Ca. It is concluded that the chemistry of cherts alone is not considered a reliable approach to resolve the critical problem of sourcing of chert artifacts, with detailed field surveys in neighboring areas and petrographic analysis needed for compelling source to artifact correlations. [ABSTRACT FROM AUTHOR]

Soft-sediment deformation (SSD) structures are widespread within the Lower Cretaceous Vigla Formation (limestones and shales) that are exposed in a 7–10 km long and 100 m high section along the east coast of Kastos Island in the Ionian Sea. SSD was observed both in limestones and in shales, and formed during or immediately after deposition, during the first stage of sediment consolidation. They are classified into six (6) different types of deformations: (1) Thick synclines and anticlines, formed due to strong synsedimentary deformation, that were produced mostly from N-S directed normal faults or from the interaction between normal and transfer faults, and are situated between undeformed horizons. (2) Thin slumps ascribed to normal fault activity and especially slumping in the footwall of the active fault, prograding orthogonal to the fault direction. (3) Thin to medium slumps produced from the synsedimentary interaction of N–S normal faults and E–W directed transfer faults, showing multiply directions of progradation. (4) Thin SSD related to diapiric intrusions that also associated with fault activity. (5) Thick slump horizons displaying erosional contacts with the neighboring undeformed limestones in the same horizon, resulting from gravity-driven mass-transport deposits that flowed across inclined basin floors. (6) Thin slumps, with chert nodules, within a slumped horizon, resulting from a slumping phase both after the sedimentation and after early diagenesis in carbonates deposits, but during the sedimentation of the lower Cretaceous Vigla limestones. All the above categories were characterized as seismites or deformation due to fault activity. This tectonism resulting in tilted blocks, the creation of space in hangingwall downthrown blocks, and changes of inclination of the basin floor, outcrops with high lateral extent in different directions adds constraints to the geometry of slumps. The transition zone between Vigla limestones and shales showed particularly abundant deformation structures. Although the Vigla Formation limestones have low primary porosity, the presence of many SSD horizons could increase secondary porosity in this formation. [ABSTRACT FROM AUTHOR]

Lithic artifacts were still in use in Bronze Age Europe, in spite of the emergence of a new technology, namely metallurgy, during this period. In fact, stone technology continued to be used everywhere until at least the end of the Early Bronze Age, and even until the end of the Late Bronze Age in specific areas. This is especially true for Greece where lithic raw material and/or tool networks were still operating during the whole Bronze Age. During the Middle Bronze Age in mainland Greece, obsidian and high-quality chert were still widely used, especially in settlements. This raises the question of the necessity of the use of obsidian instead of a stronger or more versatile material (chert or metal). Why was volcanic glass, which required considerable investment in terms of know-how and long-distance transportation, still used in spite of the technological context (where metallurgy was already developed)? The purpose of this paper is to contribute to this debate through the use-wear analysis of obsidian tools. Artifacts from settlement levels of the Middle Helladic site of Kirrha (Phocis, Greece) have been examined. In this domestic-use context, bronze and chert were also found. The main results of this study show an exclusive form and use of obsidian: bladelets were used for cutting soft and siliceous plant matter, with the exception of Graminae harvesting activity. These results point to the specialization of the lithic industry in terms of raw materials, where sharp obsidian artefacts were employed for cutting of soft and flexible materials, depending on the relative brittleness of the rock, at least at Kirrha. Thus, among the numerous propositions concerning continued obsidian circulation during the entire Bronze Age, a functional use (at least) could be proven, if this observation is also made elsewhere in Greece. [ABSTRACT FROM AUTHOR]

Archaeologists have long acknowledged the importance of flaked stone tools in the prehistoric archaeological record of the Aegean. Over the past two decades, scholars have demonstrated the continued production and use of lithics in historical periods as well. At Isthmia, flaked stone tools have been found in deposits associated with craft, agricultural, ritual, and domestic contexts. The presence of reduction debris as well as finished tools of obsidian and chert suggests some on-site production in historical eras, but recycling of older pieces is also possible. The assemblage reflects a pragmatic response to the need for cutting, scraping, and incising tools in various periods. [ABSTRACT FROM AUTHOR]

Chert concretions in thick limestone successions preserve a more complete paragenetic sequence of diagenetic minerals than their host limestone and interbedded shale. The goal of this study was to test the possible presence of a high-temperature mineralising system in the Ionian basin of western Greece. Upper Cretaceous chert nodules were sampled at Araxos, where rocks are highly faulted and uplifted by salt diapirism, and on Kastos Island, on the flanks of a regional anticline. Chert concretions have microporosity produced by recrystallisation of opal to quartz and fractures produced in the brittle chert during basin inversion. Diagenetic mineral textures were interpreted from backscattered electron images, and minerals were identified from their chemistry. Diagenetic minerals in pores and veins include sedimentary apatite (francolite), dolomite, Fe-chlorite, Fe oxide-hydroxide mixtures, sphalerite, barite and calcite. Sphalerite is restricted to Araxos, suggesting that inferred basinal fluids were hotter and more saline than at Kastos. At Araxos, the Fe oxide-hydroxide also includes minor Cu, Zn, and Ni. Whether the transported metals were derived from sub-salt clastic rocks and basement, or from enriched Mesozoic black shales, is unclear. The effectiveness of this novel approach to understanding fluid flow history in thick limestone successions is validated. [ABSTRACT FROM AUTHOR]

The article focuses on the Neolithic chipped stone artifacts collected from three seasons of excavations at Halai in Lokris, Greece. The representative selection of 506 pieces includes 442 from the northwest section of the east quadrant of trench F2 and 64 pieces from a column of earth in the nearby trench F4. The preferred material from the earliest occupation and continued to gain popularity over chert is the obsidian. The different strata of the assemblage and its analysis is presented. Stratum one creates the impression that lithic industry is dominated by blades and stratum three presents split between blades and flakes.