<p>The lithostratigraphy, age and paleoenvironmental interpretation of Lower to Middle Jurassic carbonates in Sierra Cabrera (Almería) and Cerro de San Antón (Málaga city) add to the knowledge of the sedimentary evolution of the Maláguide Complex (Internal Zones, Betic Cordillera, southern Spain). In the Barranco de Azagador section in Sierra Cabrera, Sinemurian–Pliensbachian shallow-water carbonates show a mosaic breccia and a hardground at the top. The breccia matrix and the overlying deposits are reddish crinoid packstones with hardgrounds and ammonites late Pliensbachian in age. These features suggest an extensional breakup of an initial carbonate platform giving way to pelagic reduced sedimentation. Three overlying intervals of debris-fall breccias evidence deposition on or at the base of an escarpment. Clasts in the last breccia are Middle Jurassic oolites. In the Cerro de San Antón, shallow-water carbonates change upwards to several intervals of debris-fall breccias with clasts from underlying carbonates and a crinoid packstone matrix. Crinoid packstones with hardgrounds and late Pliensbachian-earliest Toarcian ammonites overlie the breccias. As in the Barranco de Azagador, the disintegration of the pre-late Pliensbachian carbonate platform was followed by pelagic sedimentation on or at the foot of an escarpment. The crinoid packstone is brecciated and covered with a red sandstone that also fills the spaces of laterally equivalent breccias, indicating emersion. Marine sedimentation was regained in the Middle Jurassic with ooid grainstones formed in shoals. The sedimentary evolution of both sections reflects the Pliensbachian rifting phase recognised in other areas of the Maláguide Complex, although the later evolution differs in the two study outcrops.</p>

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The Lower to middle Jurassic of the Maláguide complex (Internal Zones, Betic Cordillera, S Spain) in Sierra Cabrera (Almería) and Cerro de San Antón (Málaga)

  • Juan C. Braga,
  • Fernando Sola,
  • María José Comas-Rengifo,
  • Davide Bassi

摘要

The lithostratigraphy, age and paleoenvironmental interpretation of Lower to Middle Jurassic carbonates in Sierra Cabrera (Almería) and Cerro de San Antón (Málaga city) add to the knowledge of the sedimentary evolution of the Maláguide Complex (Internal Zones, Betic Cordillera, southern Spain). In the Barranco de Azagador section in Sierra Cabrera, Sinemurian–Pliensbachian shallow-water carbonates show a mosaic breccia and a hardground at the top. The breccia matrix and the overlying deposits are reddish crinoid packstones with hardgrounds and ammonites late Pliensbachian in age. These features suggest an extensional breakup of an initial carbonate platform giving way to pelagic reduced sedimentation. Three overlying intervals of debris-fall breccias evidence deposition on or at the base of an escarpment. Clasts in the last breccia are Middle Jurassic oolites. In the Cerro de San Antón, shallow-water carbonates change upwards to several intervals of debris-fall breccias with clasts from underlying carbonates and a crinoid packstone matrix. Crinoid packstones with hardgrounds and late Pliensbachian-earliest Toarcian ammonites overlie the breccias. As in the Barranco de Azagador, the disintegration of the pre-late Pliensbachian carbonate platform was followed by pelagic sedimentation on or at the foot of an escarpment. The crinoid packstone is brecciated and covered with a red sandstone that also fills the spaces of laterally equivalent breccias, indicating emersion. Marine sedimentation was regained in the Middle Jurassic with ooid grainstones formed in shoals. The sedimentary evolution of both sections reflects the Pliensbachian rifting phase recognised in other areas of the Maláguide Complex, although the later evolution differs in the two study outcrops.