Morphological and Multivariate Statistical Analysis of Quaternary Monogenetic Vents in the Central Anatolian Volcanic Province (Turkey): Implications for the Volcano-Tectonic Evolution

Autor: Nicolas Le Corvec, Denis Legrand, Francesco Mazzarini, Göksu Uslular, Gonca Gençalioğlu Kuşcu
Přispěvatelé: MÜ, Mühendislik Fakültesi, Jeoloji Mühendisliği Bölümü, Kuşçu, Gonca Gençalioğlu
Rok vydání: 2020
Předmět:
Zdroj: Journal of Volcanology and Geothermal Research, No 107280 (2021)
ISSN: 0377-0273
DOI: 10.31223/x54p42
Popis: The interaction and competition between magmatic and tectonic processes mostly control the spatial distribution and morphology of monogenetic volcanoes. The Central Anatolian Volcanic Province (CAVP) situated in a strike-slip environment provides a remarkable opportunity to understand this relation. In this study, we defined six monogenetic volcanic fields within the CAVP and analyzed a total number of 540 monogenetic volcanoes in terms of morphological and spatial characteristics. The morphological characteristics favour the dominant role of magmatic eruptions over the phreatomagmatic ones supported by the types of monogenetic volcanoes. The flank slopes are probably the best morphometric parameters that display a correlation with the ages, and hence its usage in the relative-dating studies might be promoted. The spatial distribution of the vents in the CAVP shows a self-similar (fractal) clustering that obeys the power-law distribution defined over a range of lower (Lco) and upper (Uco) cut-off distances. The computed fractal dimensions (Df) of the six monogenetic volcanic fields vary in the range of 1.16 to 1.80, possibly due to the slight variation in the crustal thickness and fracture distribution. Uco values interpreted as the initial depth of dike intrusions are well-correlated with the local tectonics and vary from north (8.5 to 12 km) to south (16 km). Both clustered and non-clustered vent distributions are observed in the CAVP according to the Poisson nearest neighbor analysis. The former case indicates the vents formed by a single centralized plumbing system (e.g. Erciyes volcanic complex "EVC"), while the latter refers to the formation of vents through the independent shallow or deep magma reservoirs (e.g. Acigol volcanic complex). The pre-existing fractures and the changes in the local and regional stress fields are the prevalent mechanisms for the emplacement and the spatial distribution of vents. The EVC having formed along the Central Anatolian Fault Zone (CAFZ) is here considered as a magmatic transfer zone mostly inferred from the presence of many strike-slip features, rotation of extension axis, and the radial pattern of the vents. Through the western parts of CAVP, the vent alignments are almost perpendicular to the regional extension axis and parallel to the orientation of the Tuz Golu Fault Zone (TGFZ) where the pre-existing fractures are probably the primary mechanisms on their formations. Our comprehensive approach together with the analysis of well-established literature reveals that the collision along the Bitlis suture zone in the middle Miocene and subsequent westward tectonic escape of the Anatolia along the major fault zones have mostly controlled the volcanism not only in eastern Anatolia but also in the CAVP. In this scenario, we suggest that the CAFZ has been the main mechanism for the propagation of mantle-derived magmas and completely shaped the spatial distribution of the volcanoes in the CAVP with the help of crustal-depth TGFZ and other tectonic features. Our recent findings presented here will hopefully offer new insights into the understanding of CAVP volcanism and the intended future volcanic risk assessment
Databáze: OpenAIRE