Facies analysis and geological mapping of the Triassic-Jurassic transition units (Cor tes de Tajuña and Lécera
Fms) exposed in an area of 10 km2 around Morata de Jalón locality (Zaragoza province, North Iberian
Range) allow the definition of two sedimentar y episodes controlled by normal faulting. During episode 1,
a subsident coastal salina filled with Ca-sulphates was formed in the downthrown block of two normal
faults. Erosion of the Upper Triassic units (Keuper facies and Imón Fm) and deposition of terrestrial facies
(lutites, sandstones and polymict breccias), took place in the uplifted blocks. During episode 2, tectonic
reactivation combined to long-term sea level rise, resulted in the setting of tidal flat facies, preserved as
dolomitic breccias, cellular limestones and finelly-crystalline limestones. Deposition of shallow subtidal
facies (mudstones and oolitic-peloidal and bioclastic packstones-grainstones) was favoured in the more
subsident areas of downthrown blocks. Cracking and fracturing of the early lithified subtidal carbonates
also originated the local deposition in these areas of calcareous breccias and rudites