Non-destructive spectrometry methods to study the distribution of archaeological and geological chert samples

Magnetic Properties of Cherts from the Basque-Cantabrian Basin and Surrounding Regions: Archeological Implications

“…The studied cherts appear as irregular, ellipsoidal or botryoidal nodules embedded within marls, limestones and turbidite layers, although in some cases some laminar and massive-brechoid varieties are also found (Figure 3; Tarriño et al, 2015). These cherts are not related to the primary accumulation of silica-producing organisms such as radiolarians, sponges or diatoms, but to a secondary (early diagenetic) replacement of the host rock by dissolved silica that precipitates in the form of microcrystalline quartz (Olivares et al, 2009;Tarriño et al, 2015). Cherts formed in deep marine (abyssal) sedimentary environments (e.g., Artxilondo, Kurtzia, Bidache types) are composed mainly of α-quartz, whereas those formed in shallow marine settings (e.g., Urbasa) and continental environments (e.g., Ablitas, Loza, Treviño) are composed of both α-quartz and moganite (Olivares et al, 2009).…”

“…These cherts are not related to the primary accumulation of silica-producing organisms such as radiolarians, sponges or diatoms, but to a secondary (early diagenetic) replacement of the host rock by dissolved silica that precipitates in the form of microcrystalline quartz (Olivares et al, 2009;Tarriño et al, 2015). Cherts formed in deep marine (abyssal) sedimentary environments (e.g., Artxilondo, Kurtzia, Bidache types) are composed mainly of α-quartz, whereas those formed in shallow marine settings (e.g., Urbasa) and continental environments (e.g., Ablitas, Loza, Treviño) are composed of both α-quartz and moganite (Olivares et al, 2009). The early diagenetic origin of these chert types is attested by the occurrence FIGURE 1 | Synthetic map of the Basque-Cantabrian basin and surrounding regions with the location of the chert types studied in this work (after Tarriño et al, 2015).…”

“…of some faints of microfossils embedded within the chert, which results in minor amounts (<2%) of calcium carbonate and organic matter. Fossils embedded occasionally within chert include planktonic foraminifera in the case of deep marine types (Artxilondo, Kurtzia, Bidache types), large benthic formanifera and echinoderms in the case of shallow marine types (Urbasa), and gastropods, ostracodes, and algal laminations in the case of continental types (Ablitas, Loza, Treviño; see Olivares et al, 2009;Tarriño et al, 2015). Chert samples were collected from their host rocks in 8 localities (Urbasa cherts were sampled at two sites).…”

Identification of local and allochthonous flint artefacts from the Middle Palaeolithical site ‘Abrigo de la Quebrada’ (Chelva, Valencia, Spain) by macroscopic and physicochemical methods

“…However, their proportion and the presence of impurities such as calcite, iron oxides, organic matter or other compounds make its characteristics and composition variable from area to area of the sample. [17,18] In other words, one of the limitations of the chemical characterization of flint is its heterogeneity. Although EDXRF is a suitable analytical technique to obtain qualitative and/or quantitative data for most elements of the periodic table, these data come from a limited area of the sample defined by the X-ray beam size, and then many measurements are necessary on a same sample.…”

Aprovisionamiento de sílex en el Prepirineo oriental durante el Paleolítico superior antiguo: el nivel arqueológico 497C de Cova Gran (Santa Linya, Lleida)

“…Desde los estudios iniciales sobre aprovisionamiento de materias primas (Demars 1982(Demars , 1989 ( 1), Geneste 1988;Turq 1989) se ha evolucionado hacia el uso de técnicas de la Geología, que permiten caracterizar de forma objetiva las rocas empleadas en la confección del instrumental (Terradas 1995;Tarriño 2006;Fernandes et al 2007;Navazo et al 2008;Olivares et al 2009;Parish 2011). En nuestra investigación hemos elegido tres ya clásicas: los estudios petrográficos a partir de descripciones tanto macroscópicas como microscópicas (láminas delgadas) y la Difracción de Rayos X (DRX) que han permitido caracterizar los recursos de la región e identificar el origen del 99,2 % de las piezas de la unidad arqueológica 497C.…”