Radiometric ages and time–space distribution of volcanism in the Campo de Calatrava Volcanic Field (Iberian Peninsula)

• Published in: Journal of Iberian geology Vol. 47; no. 1-2; pp. 209 - 223
• Main Authors: Ancochea, Eumenio, Huertas, María José
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.05.2021; Springer Nature B.V
• Subjects: Basalt; Earth and Environmental Science; Earth Sciences; Geology; Radiometric dating; Research Paper; Rocks; Structural Geology; Volcanoes; Iberian Peninsula; Campo de Calatrava volcanic field; Región volcánica de Campo de Calatrava; Monogenetic volcanic fields; Edades radiométricas; Vulcanismo cenozoico europeo; Campos volcánicos monogenéticos; Radiometric ages; European Cenozoic volcanism
• ISSN: 1698-6180; 1886-7995
• DOI: 10.1007/s41513-021-00167-y

The volcanic region of Campo de Calatrava, which is located in the centre of the Iberian Peninsula, is characterized by monogenetic, strombolian and hydromagmatic volcanic activity. It is made up of more than two hundred volcanoes distributed over an area of about 4000 km 2 . They are mainly comprised of sodic alkaline and ultra-alkaline rocks, few evolved rocks (basalts, basanites, olivine nephelinites and olivine melilitites) and occasionally ultrapotassic rocks (olivine leucitites) and carbonatites. New radiometric ages (K/Ar and 40 Ar/ 39 Ar) allow a better understanding of the distribution and temporal evolution of volcanic activity in this region. The oldest volcanism is ultrapotassic and restricted to a single vent. The new 40 Ar/ 39 Ar ages date this centre between 7.4 Ma and 7.1 Ma, so it was contemporary with other ultrapotassic activity in the Iberian Peninsula (the lamproites of the SE of Spain). After a break of about 3 million years, the main volcanic activity in the region took place, without apparent major pauses, from about 4 Ma to less than 0.7 Ma, with most radiometric ages concentrated between 3.5 and 1.5 Ma. Except in the case of olivine leucitites, there are no significant compositional differences related to the ages of the volcanoes, although there may be minor variations. The mildly alkaline volcanoes (basalts and basanites) tend to be concentrated in the central areas of the region, while on the peripheral areas, the volcanoes are essentially ultra-alkaline. The spatial age distribution of the volcanoes seems to show a shift of the volcanic activity over time towards the northeast. The spatial age distribution of the volcanoes seems to show a displacement of volcanic activity over time towards the northeast, accompanied by an increase in its intensity.