Sedimentology and stratigraphic architecture of Barremian synrift barrier island–estuarine depositional systems from blended field and drone‐derived data

Abstract

The Lower Cretaceous (Barremian) Camarillas Formation in the Galve Sub‐basin of eastern Spain is an exceptionally muddy, synrift, aggradational then retrogradational paralic succession. Deposition within these arid, equatorial paralic systems was strongly controlled by crustal rifting of the Iberia plate linked to the geodynamic evolution of the Atlantic Ocean, the Bay of Biscay and the Tethys Ocean. Although synsedimentary extensional tectonics controlled thickness and facies distributions, the parasequence stacking patterns point to a superimposed high‐order allogenic control on the paralic succession. Field data and drone imagery are combined to document changes in sedimentology and three‐dimensional stratigraphic architecture of these deposits to interpret changes in depositional environments as this basin filled. Three evolutionary stages are identified: (i) tide‐dominated estuary; (ii) mixed‐energy estuary, with a well‐developed wave‐dominated barrier island system; and (iii) barrier island–tidal inlet suite. An exceptional record of back‐barrier‐island depositional interactions is preserved in this high‐subsidence, extensional‐basin setting, including deposition of washover fans, flood‐tidal deltas and ebb‐tidal deltas. Drone‐derived imagery facilitates three‐dimensional architectural characterization of these complex paralic deposits, including multi‐episodic tidal inlets, and correlation of basin scale stratigraphic markers. Spatio‐temporal interactions between climate change, sea‐level variations and rift‐related subsidence generated complex estuarine and barrier island geobodies. The general transgressive trend recorded in the Camarillas Formation correlates well with global eustatic sea‐level rise during the Barremian.