Abstract Sierra de la Estrella outcrops belong to the Sierra del Castillo Unit, which is defined in the Guadiato Area, SW Spain, where sedimentation occurred during the Late Viséan. The Guadiato Area is located on the boundary between the Ossa-Morena and Central Iberian structural zones, in the southwestern Iberian Peninsula, where Lower Carboniferous outcrops are common. The stratigraphic succession from Sierra de la Estrella is dated precisely by means of foraminifers (Zone 15). The studied rocks are interpreted as having developed on a storm-dominated ramp. Microbial buildups occur interbedded between tempestites and marls. Two main types of mud mounds have been distinguished: large tabular and smaller dome-shaped mud mounds, which were developed in a middle-ramp setting.

Abstract Dome-shaped mud mounds ranging in size from 2 m to 25 m thick and from 2 m to 100 m in diameter are present in the Upper Viséan of Sierra de la Estrella, Guadiato Valley, in the Sierra Morena region of SW Iberian Peninsula. The mounds are composed of up to 70% peloidal matrix and contain a varied but sparse assemblage including bryozoans, crinoids, brachiopods, calcareous algae, foraminifers, and gastropods. A three-stage biotic succession is recognizable in the mounds. The first stage consists of crinoid-sponge spicule packstones. The second stage is represented by a low-diversity, autochthonous assemblage of scattered sponges and up to 40-60% by volume of the microproblematical taxon Saccamminopsis fusulinaeformis (McCoy). The third stage consists of peloidal framework and cementstone with abundant primary growth cavities. These rocks are interpreted to be microbial boundstone-cementstone. The three stages of mound growth developed below storm wave base, and the probable coeval, level-bottom beds consisting of marls are interpreted to have been deposited in a dysphotic environment.

Abstract Cretaceous rocks crop out extensively in the three main Alpine orogenic belts of Spain: the Betic Cordillera, the Pyrenees and the Iberian Ranges. These rocks, deformed during Cenozoic Alpine convergence, are almost entirely sedimentary (with the exception of rare volcanic and meta-morphic rocks) and were deposited in an enormous variety of environments ranging from alluvial fans to pelagic seas. There were four main basins – Betic, Pyrenean, Basque-Cantabrian and Iberian (Fig. 12.1 ) – each of which originated in Triassic and Jurassic times in response to continental break-up at the start of the Alpine cycle. They subsequently underwent a polyphase evolution in the Cretaceous period when palaeo-geography and sedimentation in Iberia were strongly influenced by the relative movements of the contiguous Eurasian and African plates. Initiation of the North Atlantic spreading in earliest Cretaceous time led to a decrease in relative sinistral motion between Iberia and Africa (e.g. Ziegler 1988 a ). This was followed by a phase of rapid counterclockwise rotation of Iberia relative to Europe and the progressive opening of the Bay of Biscay, which lasted from late Aptian to early Campanian times (e.g. Olivet 1996 ). Finally, a third phase of basin evolution was heralded by the onset of Late Cretaceous oblique convergence between Africa and Europe (e.g. Savostin et al . 1986 ; Reicherter & Pletsch 2000 ). In addition to this changing tectonic setting, other factors, such as climate and eustasy, were also important controlling influences. The Cretaceous climate of Iberia

Abstract Name: Iberian seaway Authors: Angela Alonso, Marc Floquet, Ramon Mas, and Alfonso Melendez Location: From 39° to 43º north latitude and 0° to 5° 30' west longitude, Iberian Range, Spain Geologic time interval: Late Cretaceous, middle Albian to latest Maastrichtian Tectonic-sedimentary setting: Iberian plate; stable cratonic areas between Bay of Biscay (Cantabrian) opening and Tethyan closing Basin type: Epeiric platform Paleoclimate: Albian to late Santonian, warm and humid; Campanian, warm and semiarid; Maastrichtian, warm and humid Platform type: Ramps, shelf Platform geometry: Seaway oriented northwest-southeast, 500 km long, 250–350 km wide, and 500–1300 m thick Facies and fossils: Micrites, marls, fine and coarse carbonates, minor amounts of evaporites and sandstones. Benthic and planktonic foraminifera, ammonites, rudists, molluscs, and algae Systems tracts: Best represented are shallow ramp highstand system tracts; second are transgressive system tracts; lowstand system tracts are not represented Stacking patterns: Retrogradational onlaping and progradational (sometimes sigmoidal) to aggradational parasequence sets