Abstract
AbstractTwo Kimmeridgian shallow-marine carbonate successions (mid-shelf), sharing a similar paleoclimatic framework (climatic zone), were previously explored using carbonate chemostratigraphy. Before, the goal was to detect signals related to paleoplatform bottom physiography, degree of connection with oceanic waters and overall circulation patterns. In this contribution, complementary bulk mineralogical composition and clay mineral fractions are investigated to contrast and complement previous information, aiming for a more complete overview of continent-ocean dynamics along shallow-carbonate platforms of southern Iberia. The goal is now to explore complex patterns of continental influence along proximal settings and their relative spatial distribution across differentiated settings without relevant difference in paleolatitude. The choice of both stratigraphic sections is based on this distinctness: Rocha Poço (Algarve Basin, Portugal) represents a more restricted and relatively proximal setting, in contrast to Puerto Lorente (South Iberian Paleomargin, S Spain) placed at a relatively more open and probably distal shallow-water context. Accordingly, quartz content was higher at Rocha Poço, especially at the lower siliciclastic interval of this section. Quartz contribution fades out at Puerto Lorente, where it was mainly controlled by short-lived terrigenous pulses. Clay mineral assemblages also differed, being more varied (smectite, illite and traces of kaolinite) and abundant at Rocha Poço, and generally leaner at Puerto Lorente. At the latter site, terrigenous pulses do not contribute to clay mineral abundance, only showing abundant illite at the topmost horizons. New information retrieved from mineralogical data provided evidence on depositional contrasts resulting from local differences in platform configuration, allowing a better understanding of mechanisms controlling the terrigenous fraction in the shallow-water carbonates analyzed.
Funder
MICINN, MINECO
Research Groups RNM-178, Junta de Andalucía, Spain
Geobiotec-UA
Universidade de Aveiro
Publisher
Springer Science and Business Media LLC
Reference159 articles.
1. Abbink, O., Targarona, J., Brinkhuis, H., & Visscher, H. (2001). Late Jurassic to earliest Cretaceous palaeoclimatic evolution of the southern North Sea. Global and Planetary Change, 30(3–4), 231–256.
2. Acosta, P. (1989). Estudio del Jurásico de un sector de la Sierra de Cazorla (Zona Prebética), Bachelor Thesis. Univ.
3. Adler, L. B. (2013). The taphonomy of soft-bodied cnidarians (p. 286). UCD School of Geological Sciences, University College Dublin, Ireland.
4. Andrieux, J., Fontboté, J. M., & Mattauer, M. (1971). Sur un modèle explicatif de l’Arc de Gibraltar. Earth and Planetary Science Letters, 12, 191–198.
5. Angrand, P., & Mouthereau, F. (2021). Evolution of the Alpine orogenic belts in the Western Mediterranean region as resolved by the kinematics of the Europe-Africa diffuse plate boundary. Bulletin De La Société Géologique De France—Earth Sciences Bulletin, 192(42), 1–44.