Abstract-We present the biostratigraphy (ammonites, brachiopods, fo raminifers, and ostracodes), lithos tratigraphy, sedimentology, sequence stratigraphy, magnetostratigraphy, and isotope stratigraphy of the Almonacid de la Cuba section located in the Iberian Range, central-eastern Spain. This section, which con tains a continuous and expanded record of the Pliensbachian-To arcian boundary (Early Jurassic), has been proposed as a complementary section for the Toarcian GSSP. An excellent ammonite -based biozonation has been obtained. Four ammonite assemblages characterized by the presence of Pleuroceras, Canavaria, Dactylio ceras (Eodactylites ), and Dactylioceras (Orthodactylites) have been distinguished. The base of the To arcian is located at level eU35.2, based on the fi rst occurrence of Dactylioceras. The occurrence of taxa fr om the NW European and the Mediterranean provinces is useful to improve the correlation between both provinces. Fo r aminiferal and ostracode assemblages are rich and diversified and no significant biostratigraphic events take place at the Pliensbachian-To arcian boundary. The magnetostratigraphic data presented here are the most complete record of reversals of the earth magnetic fi eld for the Pliensbachian-To arcian boundary. A good record of the onset of the positive o13e excursion reported in the Lower To arcian of many European sections has been obtained. Ave rage paleotemperatures measured at the latest Pliensbachian Spinatum Biochron of about 12.5°e, recorded a marked increase of the seawater temperature which started durin� the To arcian , reaching average temperatures of 16.rC at the Te nuicostatum Biochron. The obtained 87 Sri 6 Sr va lues fully agree with the LOWESS calibration curve .

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A palaeomagnetic investigation has been carried out at 14 sites on Jurassic red nodular limestones from the central and eastern part of the External Zones of the Betic Cordillera (Subbetic and Prebetic Zones). Progressive thermal demagnetisation of samples from the Subbetic Zone reveals the presence of two stable magnetic components of the natural remanent magnetisation: 1) a secondary Neogene syn-folding component and 2) the original Jurassic magnetisation. As similar characteristics have been reported in Jurassic limestones from the western Subbetic Zone, a widespread remagnetisation event took place within <10 6 years in the entire Subbetic region during Neogene times. In contrast, in the Prebetic region, no evidence for a secondary overprint has been detected. Palaeomagnetic Jurassic declinations indicate variable and locally very large clockwise rotations (35°-140°), but the two sites in the north-westernmost part of the investigated region are not rotated. The use of both components of magnetisation and the incremental fold-test results allowed the timing of block rotations in the Subbetic Zone to be constrained. Rotations in the western Subbetic occurred after the acquisition of the secondary overprint, whereas in the central part of the Subbetic Zone they were completed by the time of the remagnetisation event.

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