Blesa Formation

Blesa Formation
Stratigraphic range: Barremian PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Unit of	Maestrazgo Basin
Sub-units	Upper Blesa Sequence - Valdejunco Member Middle Blesa Sequence - Josa Member Lower Blesa Sequence - Cabezo Gordo Member, Morenillo member
Underlies	Alacón Formation
Overlies	Unconformity with Jurassic strata
Thickness	Up to 150 m
Lithology
Primary	Clay, Marl, Limestone
Other	Conglomerate
Location
Region	Europe
Distribution of the Belsa Formation within the Oliete Sub-Basin (in olive)

The Blesa Formation is a geological

The Belsa Formation is found within the Maestrazgo Basin. Within the stratigraphic sequence it overlies Jurassic rocks in a syn-rift unconformity, and underlies the Alacón Formation.

The formation is up to 150 metres thick and is divided into three distinct unconformity bounded units, which are called the Lower, Middle and Upper Blesa Sequences. The Lower Blesa sequence varies greatly in thickness from less than 10 m up to 100 m is divided up into two members, the lower Cabezo Gordo Member, which consists of red clays and the upper Morenillo Member, which consists of limestones and marls, both of these sequences were deposited in a continental setting. The Middle Blesa Sequence is of a fairly uniform 25-50 metre thickness. Most of the sequence consists of the Josa Member, which consists of oyster rich marls and limestones deposited in a coastal or shallow restricted bay environment. The Upper Blesa Sequence is of variable thickness from 15–70 m. The lower 1–10 m consists of continentally derived clays and marls with sandstone and conglomerate intercalations while the upper 10–60 m are dominated by carbonates.^[1]

Early Cretaceous stratigraphy of Iberia

Ma	Age	Paleomap \ Basins	Cantabrian	Olanyà	Cameros	Maestrazgo	Oliete	Galve	Morella	South Iberian	Pre-betic	Lusitanian
100	Cenomanian		La Cabana	Sopeira	Utrillas		Mosquerela					Caranguejeira
			Altamira		Utrillas
			Eguino
125	Albian		Ullaga - Balmaseda	Lluçà						Traiguera
			Monte Grande		Escucha		Escucha			Jijona
			Itxina - Miono
	Aptian		Valmaseda - Tellamendi		Ol Gp. - Castrillo	Benassal		Benassal				Olhos
				Font	En Gp. - Leza	Morella/Oliete	Oliete	Villaroya	Morella	Capas Rojas		Almargem
			Patrocinio - Ernaga	Senyús	En Gp. - Jubela	Forcall				Villaroya	Upper Bedoulian	Figueira
	Barremian		Vega de Pas	Cabó	Abejar	Xert	Alacón	Xert		Huérguina		Assises
				Prada		Artoles				Collado	Moutonianum	Papo Seco
				Rúbies	Tera Gp. - Golmayo	Alacón/Blesa	Blesa	Camarillas	Mirambel
150	Hauterivian				Ur Gp. - Pinilla	Llacova		Castellar	Tera Gp. - Pinilla	Villares		Porto da Calada
							hiatus
						Huerva			Gaita
	Valanginian		Villaro		Ur Gp. - Larriba				Ped Gp. - Hortigüela
					Ped Gp. - Hortigüela				Ped Gp. - Piedrahita
					Peñacoba			Galve		Miravetes
	Berriasian		Cab Gp. - Arcera		Valdeprado	hiatus		Alfambra
					TdL Gp. - Rupelo			Arzobispo	hiatus	Tollo
					On Gp. - Huérteles Sierra Matute
	Tithonian		Lastres		Tera Gp. - Magaña		Higuereles			Tera Gp. - Magaña		Lourinhã
									Arzobispo
					Ágreda
Legend		ichnofossiliferous, coproliferous , minor formation
Sources

• List of dinosaur-bearing rock formations