Ice-rafted dropstones at midlatitudes in the Cretaceous of continental Iberia

Rodríguez-López, Juan Pedro ; Liesa, Carlos L. (Universidad de Zaragoza) ; Luzón, Aránzazu (Universidad de Zaragoza) ; Muñoz, Arsenio ; Mayayo, María J. (Universidad de Zaragoza) ; Murton, Julian B. ; Soria, Ana R. (Universidad de Zaragoza)

Resumen: The Cretaceous is widely considered to have been a period subjected to super-greenhouse conditions. Here, we provide multiscale sedimentologic evidence of glaciers developing at mid-paleolatitudes (∼45°N) in continental Iberia during the Hauterivian cold snap. Striated and faceted ice-rafted glacial dropstones (cobble to boulder size) and striated and grooved silt- to sand-sized grains (ice-rafted debris [IRD]) occur in a lacustrine sequence of the Enciso Group in the eastern Cameros Basin, Spain. The ice-rafted materials constitute the first evidence reported for a Cretaceous continental cryospheric record in Europe, and they are attributed to calving of glacier snouts, releasing icebergs into an ice-contact lake. The sedimentary succession resembles glacial-deglacial records in lakes overridden by the late Pleistocene Laurentide Ice Sheet in eastern Arctic Canada. The Iberian glacial succession was coeval with plateau permafrost in Asia and IRD records in the Arctic and Australia, revealing a stronger than previously thought cryosphere during the global Hauterivian cold snap.

Idioma: Inglés

DOI: 10.1130/G51725.1

Año: 2024

Publicado en: Geology 52, 1 (2024), 33–38
ISSN: 0091-7613

Financiación: info:eu-repo/grantAgreement/ES/AEI/PID2019-108705GB-I00
Financiación: info:eu-repo/grantAgreement/ES/DGA/E32-23R

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Geodinámica Interna (Dpto. Ciencias de la Tierra)
Área (Departamento): Área Estratigrafía (Dpto. Ciencias de la Tierra)
Área (Departamento): Área Cristalografía Mineralog. (Dpto. Ciencias de la Tierra)