Materiales redepositados del Jurásico Superior-Cretácico InferiorCronoestratigrafía y Génesis (Unidad del Ventisquero, zona Subbética, Jaén)

  1. G.A. de Gea
  2. L.M. Nieto
  3. R. Aguado
  4. J.M. Molina
  5. P.A. Ruiz Ortiz
Journal:
Geotemas (Madrid)

ISSN: 1576-5172

Year of publication: 2000

Issue Title: V Congreso Geológico de España (Alicante, 10-14 julio 2000)

Issue: 1

Pages: 183-186

Type: Article

More publications in: Geotemas (Madrid)

Abstract

A detailed biostratigraphic study of late Jurassic and early Cretaceous rocks from the Ventisqueros - del Trigo Unit (Subbetic Zone, South of Jaén), mainly based on calcareous nannofossilsand calpionellids, has been performed. The chronostratigraphic analysis of the different formations near the Jurassic-Cretaceous boundary indicates an important complexity in their relationships. Very close to this boundary it has been detected a stratigraphic break whose associated hiatuscovers, depending on locations, a variable time interval (about 4.2 to 12.4 m.y.). Also associated to the rocks of this unit, and near the Jurassic-Cretaceous boundary, reworked materials (polygenicbreccias, pebbly mudstones and slumps) are common. The polygenic breccias are located infive chronostratigraphic levels: earliest Tithonian, late Tithonian, early Valanginian, earlyHauterivian and late Hauterivian.