Vol. LEIDSE GEOLOGISCHE MEDEDELINGEN, 39, pp. 129—192, published separately 5-4-1967 Devonian and Lower Carboniferous Conodonts of the Cantabrian Moun- tains (Spain) and their stratigraphic application BY H.A. van Adrichem Boogaert Summary of the literature the of the Devonian and the Lower Carboniferous ofthe Cantabrian Mountains A short review on stratigraphy precedes the report of the author's stratigraphic and palaeontologic observations in León: the Río Esla area (Gedinnian to central Cantabrian and the Gildar-Montó area in Asturias: Viséan), the area (Famennian to Viséan), (Eifelian to Viséan); the coastal area (Frasnian to Viséan); in Palencia: the Arauz-Polentinos area (Gedinnian to Givetian), the Cardaňo-Triollo and San Martín-Valsurvio area and Famennian and in Santander: the area (Eifelian to Viséan), the (Givetian to Viséan); Liébana area (Eifelian to Viséan). which extracted from calcareous could be in the zonal succession Most of the conodont faunas, were formations, arranged established in Germany, and thus supplied new data about several formations in the Cantabrian Mountains. The of the Ermita Formation in Asturias and Palencia is demonstrated. The of this unit presence transgressive age ranges from Famennian Tournaisian. The Cardaňo Formation from middle maximally uppermost to lowermost ranges or upper Givetian Frasnian. The Vidrieros Formation from the of the lower Famennian the lowermost to upper ranges upper part to Tournaisian. A synthesis of the stratigraphic data delimits the Palentine facies area, which is clearly separated from the Asturo-Leonese The units the Asturo-Leonese the Palentine facies area by positive areas. following palaeogeographic are distinguished: Basin, Basin, and the Asturian Geanticline. The development of these units from the Middle Devonian to the Lower Carboniferous is The sedimentation the Asturian Geanticline limited and incom- demonstratedby eight facies-pattern maps. on was probably plete. An epeirogenetic uplift of this geanticline took place in late Frasnian to early Famennian times. This uplift is correlated sheltered Palentine with the deposition of the quartzitic Murcia Formation in the Basin. The uplifted area was covered by the Ermita transgression in the late Famennian to early Tournaisian. resulted in the Formation in the Tournaisian. In After a break in the sedimentation, a local transgression Vegamian upper in the Tournaisian lower Viséan. In the Palentine Basin the most ofthe area the Alba transgression began uppermost or deposi- started in the Viséan. tion of the Alba Formation upper with the zonal forms of the conodonts. Three elements The chapter onsystematics deals mainly most important guide new are from the middle from the described: Icriodus eslaensis n.sp. to upper Givetian, Siphonodella? n.sp. a, probably upper Tournaisian, and A conodont from the Gedinnian lower n.gen. n.sp. a, a simple compound upper or Siegenian. Contents 130 III. Zonation and of the Introduction dating stratigraphic sequence by means of conodonts 155 I. General outline ofthe stratigraphy ofthe Devonian The biostratigraphic framework 155 and Lower Carboniferous of the Cantabrian Conodont zones demonstrated in the Canta- 131 Mountains brian Mountains 155 Leon 131 Asturias 131 IV. Discussion of the new data with respect to the Palencia 132 Devonian and the Lower Carboniferous forma- tions in the Cantabrian Mountains 158 General remarks 133 Devonian lowermost 159 (and Tournaisian). ... 134 The Asturo-Leonese facies area 159 II. Stratigraphic and palaeontologic observations . Leon 135 The Ermita Formation 159 135 The facies 161 The Rio Esla area Palentine area 138 The Abadia Formation 161 The central Cantabrian area 141 The Formation 161 The Gildar-Monto area Gustalapiedra 145 The Cardafio Formation 161 Asturias, coastal area Palencia 146 The Murcia Formation 162 146 The Vidrieros Formation The Arauz-Polentinos area 162 149 Lower Carboniferous 162 The Cardafio-Triollo area The Formation 163 The San Martin-Valsurvio area 153 Vegamian 154 The Alba Formation 164 Santander, the Liebana area 130 H. A. Adrichem Conodonts Cantabrian van Boogaert: of the Mountains V. Palaeogeographic synthesis of the stratigraphic The Lower Carboniferous development of the data 166 sedimentary basins 177 General remarks 166 VI. Conodont systematics 177 The Asturian Geanticline 169 Samenvatting 188 The and of the location, nature, development Sumario 188 Devonian sedimentary basins 173 References 189 The Asturo-Leonese Basin 173 3 Plates The Palentine Basin 175 6 Enclosures INTRODUCTION The formed of San Isidro and Tarna Adrichem Boo- present study part a geological investiga- pass pass (van of the tion of the southern Cantabrian Mountains which gaert et al., 1963). Sampling and surveying sur- to has been carried out since 1950 by staff members and roundings of the Pico Gildar and, more the east, basis for students of the University of Leiden, starting in the Cardano-Triollo area, provided the a northern Palencia. This study was gradually extended conodont stratigraphy of these regions. In 1965 a westwards, and in 1964 reached the westernmost final field trip was made to obtain additional data to in the southern of of the observations occurrence of the Devonian, part complete a synthesis stratigraphic "Asturian Knee". The the provisional geological map already compiled. of the southern slope of the Cantabrian Mountains Acknowledgements. — During the preparation of this of the thesis the author received and advice (de Sitter, 1962) provides a general picture area. special help As of detailed and from Sincere thanks are extended part a more stratigraphic palaeon- many persons. to of directed A. Dr. W. Landesamt Nordrhein- tologic investigation the area by prof. Dr. Ziegler (Geologisches Brouwer (Department of Stratigraphy and Paleonto- Westfalen, Krefeld, Germany), who guided the logy), the present author started a study of conodonts author's first step in conodont techniques and system- in 1959. atics. Thanks are also due Prof. Dr. O. H. Walliser of Initially, conodont faunas were obtained from Devo- (Gottingen, Germany) for the discussion problems the author with nomenclature and Lower Devonian nian rocks from the Rio Esla area, where respect to carried out stratigraphic fieldwork in the Esla conodontstratigraphy. Dr. P. Bender (Marburg/Lahn, the conodont autochthone from 1959 to 1961, but they were not Germany) kindly showed the author this collections of the of The author very abundant in area. Samples provided by University Marburg. is A. Mr. I. B. H. M. Rubbens in 1959 from the Pico also very grateful to Dr. J. G. Binnekamp, Mr. J. indicated Mr. A. Mr. R. W. Lan- Gildar, situated more to the north, a more van Hoeflaken, J. Kutterink, promising area for the study of conodonts. The results ting, Dr. N. Sjerp, and Dr. J. van Veen for providing his of sampling to the west of this area, near the water- samples or putting field data at disposal. Mrs. contributed I. assisted with the text. shed, to a new stratigraphic interpretation Seeger-Wolf English of Palaeozoic sections in the region between the 1. Situation of the Cantabrian Mountains The shaded shows the Fig. map (1 : 6,000,000). quadrangle general region of the study. General outline of the stratigraphy 131 CHAPTER I GENERAL OUTLINE OF THE STRATIGRAPHY OF THE DEVONIAN AND LOWER CARBONIFEROUS OF THE CANTABRIAN MOUNTAINS The Cantabrian Mountains (Fig. 1 ) have long Special attention has been paid by Wagner (1957, attracted the attention of geologists, to whom they 1963), Wagner-Gentis (1963), and Kullmann (1961, offer excellent fossil and mineral and Alba exposures, riches, 1962, 1963a) to thecephalopodsofthe Formation, interesting structures. Many papers on this mountain which indicate that this formationranges in age from chain been in of the last Lower Visean Visean. Namurian have published the course to Upper Lower Publications with modern strati- were found in the lowermost beds of the century. dealing a goniatites of of it of direct Caliza transitionalbeds between graphic analysis the area or parts are de Montana or in the importance for this paper. A review of these publica- the Alba Formation and this limestone. tions is given below. Higgins (1962) reported on conodonts of the Alba Formation in Leon and Palencia. In an investigation LEÓN of the Devonian-Carboniferous transition in the southern of the Rio Bernesga region, Higgins The stratigraphy of the Lower Palaeozoic and the part et al. identified Tournaisian conodonts. Devonian in the northern of with the (1964) part Leon, New data the of near the of the northeasternmost is based on stratigraphy Leon, exception part, on al. watershed, reported by van Adrichem Boogaert et the work of Comte (1959), who distinguished as revealed the of the Ermita Formation Devonian and Lower Carboniferous units: (1963), presence overlying Ordovician quartzites. The Lower Palaeo- Griotte de Puente de Alba zoic of these had been age quartzites already correctly Couches de Vegamian Viseen estimated by Julivert (1960) and Martinez Alvarez lacune (1962) in Asturias. Sjerp (1967) has recently presented Gres de l'Ermitage Strunien lacune further details about the stratigraphy of this area. of Schistes de Fueyo Famennien Rupke (1965) published data on the structure the Rio Esla in which he dealt with the area, stratigraphy Calcaires de Valdore Galcaire. Portilla gasmen of the "Esla nappe", the "Esla autochthone", and the Gres et Schistes de Huergas _,,., "Las Salas zone" the northern of the (in part area Calcaires de