title: Tithonian and Lower Berriasian calpionellid against ammonite biostratigraphy of the Dvuyakornaya Formation in eastern Crimea
abstract: The Dvuyakornaya Formation in eastern Crimea of late Kimmeridgian to Berriasian age represents a thick flysch-like succession of clays, marls and less common limestones. The ammonite zonation includes incomplete record from the Beckeri Zone in the uppermost Kimmeridgian up to the Jacobi Zone in the Lower Berriasian. Two main sections have been micropalaeontologically studied – the Dvuyakornaya Buhta and the Cape Svyatogo Ili’i. Eighteen calpionellid species of the genera Longicollaria, Chitinoid
journal: Geologica Balcanica