HETTANGIAN AND SINEMURIAN OF BANOS DE ALHAMA DE GRANADA

REFERENCE SECTION FOR THE WEST-MEDITERRANEAN HETTANGIAN

(BETIC CORDILLERA, SOUTHERN SPAIN)

by

JUAN-CARLOS BRAGA *, AGUSTIN MARTIN-ALGARRA ** & PASCUAL RIVAS *

ABSTRACT

Two Lower Liassic sections of the Banos de Alhama de Granada outcrop are studied. The Hettangian and Sinemurian ammonite assemblages are detailed and a reinterpretation of the stratigraphy of the outcrop made.

The ammonites collected show a clear mediterra- nean character. A biostratigraphy for the Hettangian and Sinemurian can be made but the correlation with the northeuropean zonal divisions and chronostrati- graphy is rather difficult. These are the only west mediterranean sections where a succession of Hettan- gian ammonite assemblages have been made.

RI~SUMI~

On ~tudie deux coupes du Lias inf~rieur de l'affleu- rement des Banos d'Alhama de Granada, appartenant tt la ~ Dorsale B~tique >>. Les associations d'ammoni- tes permettent d'identifier l'Hettangien et le Sin6mu- rien dans les deux s~quences. En consequence la stra- tigraphie de l'affleurement est modifi~e. On ne peut gu~re la consid~rer comme une s~quence monoclinale depuis le Trias inf6rieur jusqu'au Lias moyen, mais plutSt comme une structure anticlinale ou en ~cailles qui comporte fondamentalement des termes jurassi- ques.

Dans les associations d'ammonites de l'Hettangien moyen le genre Waehneroceras pr~domine/l c8t6 de quelques Alsatites. Schlotheimia et Vermiceras carac- t6risent l'Hettangien sup6rieur. On n'observe pas de formes du Sin6murien basal et Arnioceras est le genre le plus fr6quent dans le Sin6murien (s. strl) sup6rieur.

La faune pr6sente un caract~re m6diterran6en mar- qu6 qui rend difficile les corr61ations biostratigraphi- ques et chronostratigraphiques avec les zonations nord- europ6ennes. Les esp~ces pr~sentes sont sem- blables ~ ceUes d6crites dans d'autres domaines alpins et par contre on n'a pas trouv6 de formes propres aux s6quences du Nord-Ouest europ6en.

KEY-WORDS : MEDITERRANEAN LOWER LIASSIC, AMMONITES, BIOSTRATIGRAPHY, DORSALE B]~TIQUE.

MOTS-CLI~S : LIAS INF~RIEUR MI~.DITERRAN~EN, AMMONITES, BIOSTRATIGRAPHIE, DORSALE BI~.TIQUE.

* Dpto. Paleontologia, Univ. Granada and Dpto. Investigaciones Geol6gicas de Granada, C.S.I.C., Espagne. ** Dpto. Estratigrafia, Univ. Granada and Dpto. Investigaciones Geol6gicas de Granada, C.S.I.C., Espagne.

Geobios, n ° 17, fasc. 3 p. 269-276, 3 fig., 1 pl. Lyon, juin 1984

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~ Neogene Basins

External Zones

~ Flysch Units

Internal Zones

N I

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- - \ \ \ \ \ , , \

/ / _...----- / -

SINfNURIAN ASS[NBIAGES - ~ .

1-3

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SECIION A SECIION B

0 50 x

Fig. 1 -- 1A. Geological and geographical setting of Ba~'os de Alhama outcrop. The arrow points to the studied outcrop. lB. Alternative Interpretations of the structure of the outcrop.

IC. General Ilthologic cross-section with details of the two Liassic fossiliferous sections.

1A. Cadre g6ographlque ct g6ologique de l'affleurement de Banos de Alhama de Granada. La fl6chc indique l'affleurement ~tudid. lB. Deux lnterpr~tations possibles de la structure de I'afflenrement. 1C. Profll g~ologique d'ensemble et d~talls des deux successions fosslllf~res du Lias.

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INTRODUCTION

The Lower Liassic materials, fossil associations and biostratigraphy of the Ba~os de Alhama de Granada outcrop are studied (fig. 1A).

Although Silvertop (1836) mentions the outcrop, Bertrand & Kilian (1889) were the first to make a pro- per stratigraphic study noting the Lower Liassic ammonites found there. Viennot (1936) gives a sche- matic cross-section, but no new data were added to the stratigraphy until Busnardo & alii's (1966) detai- led description of the southern part of the outcrop, identifiying the Hettangian, Sinemurian, Lotharin- gian and Domerian. They identified a Waehneroceras fauna of the Middle Hettangian for the first time in Spain. An accurate palaeontological study of these ammonites was subsequently made by Mouterde & Linares (1981).

Vera (1969) refers to the sequence, describing the peculiarities which distinguish it from neighbouring sections of the Zafarraya Unit. Busnardo & alii (1969) add a description of some of the levels of the northern part of the sequence, dating them as Triassic arguing from their relative geometric position in relation to the Hettangian and from data obtained from benthic Foraminifera palaeontologically studied by Ruget & Sigal (1969).

Durand-Delga & alii (1970) include the outcrop in the << Dorsale B~tique >~ paleogeographic realm.

In the Subbetic, the Lower Liassic is usually dated by benthic organisms belonging to carbonate plat- form environments (Dasycladacean Algae and Bra- chiopoda mainly). Only one ammonite (Arnioceras) has been recorded in the Sierra Elvira (Linares & Mouterde, 1962). It is the only Lower Liassic ammo- nite which has been found in the region outside the sequences considered as << Dorsale B6tique )>.

There are only very localized references in regional works to coeval ammonites in the rest of the Betic Cordillera. Apart from that of Busnardo & alii (1966), no detailed stratigraphic studies have been made. The Hettangian is also known in the Nieves sequence in which Dt~rr (1967) cites:Ectocentrites petersi, Psiloceras sp. and Schlotheimia angulata. Sinemurian ammonites, mainly Arnioceras are more frequently quoted, some of them in the Serrania de Ronda and others in the Sierra Harana. All of the sequences already cited are considered by Durand- Delga & alii (1970) as belonging to << Dorsale B~ti- que >> realm.

The present study grew out of a student study of one of the authors (M.A.), who found ammonite remains in the northern part of the Ba~os de Alhama outcrop. Subsequent more detailed sampling have revealed the relative abundance of ammonite faunas from the two different sequences, the southern coinci- ding with that already described by Busnardo & alii (1966) and the northern described here for the first time.

SOME GEOLOGICAL CONSIDERATIONS

The Ba'~os de Alhama de Granada sequence under- lies the Upper Miocene of the Granada Basin, and no geological relations with other preorogenic sequences are visible. It is almost certainly confined to the bor- der between the External and Internal Zones of the Betic Cordillera, as has been suggested by other authors in the case of other tectonically complicated units with similar stratigraphic features.

The tectonic and palaeogeographic relation of all these Units is still a matter for discussion. The French School, in particular, includes them in the << Dorsale B~tique )> and suggests a marginal position in the Internal Zones of the Cordillera, while others call them <t Rondaides >~ and suppose that they are tecto- nic pieces of the Mesozoic and Cenozoic cover of at least part of the Internal Zones.

The analogies between these Units and the Calca- reous Ranges (<< Chatne Calcaire >>) of the North African Cordillera from the Rif to Calabria are clear, and the same origin for all has been suggested, these units being a feature common to the West Mediterra- nean Cordilleras.

StratigraphycaUy, it is possible to distinguish bet- we~en the Internal and External Dorsal, and the Bafios de Alhama de Granada sections can be included in the latter. The External Dorsal is characterized by the presence of a dolomitic Upper Triassic, calcareous and marly alternation in the Rhaetian and a well deve- loped pelagic Liassic, frequently containing Sinemu- rian red nodular limestones. The rest of the Mesozoic series is usually highly reduced or absent. In the out- crop studied, only the Lower Liassic is dated in both

272 - -

of the sections. In the southern sequence, Busnardo & alii (1966) also record the Middle Liassic (Domerian) dated by ammonites.

The Ba~os de Alhama de Granada cross-section consists of a nearly vertical, well stratified marly and calcareous assemblages dipping to the North and highly tectonized, the contacts between consistent and weak materials usually being faulted and/or brechi- fled.

The sequence has been interpreted as a southern reversed monocline and, accordingly, the rocks appearing below the Middle Hettangian of the sou- thern section are attributed to a pelagic Triassic. The dating of the northern part of the sequence as Lower Liassic with a stratigraphic evolution similar to, but

not identical with the southern one, lead us to consi- der the general structure of the outcrop as an anticline with a laminated flank [fig. 1B(I)] or a scalelike struc- ture [fig. 1B(II)].

On the other hand, the ascription of all the central part of the sequence, in which ammonites have been not found, to the Triassic is also questionable, because almost all the facies present are similar to that of the Liassic identified in both sections. The undated part may correspond to a strongly folded and faulted part of Liassic sequences. It should be remembered that a pelagic Triassic would not have equivalents in every Western Mediterranean Cordilleras [cf. i.e. Bosellini & Hs0 (1973)].

STRATIGRAPHIC SECTIONS

In figure 1C, the geological cross-section along the road from the Bafios of Alhama de Granada running parallel of the Alhama River is shown, with the two detailed stratigraphic sections established. In the same figure, the correlation between both sections is also given. The following description is based on the featu- res of the southern section (A) and only refers to those of the northern section (B) when they differ.

The sections begin with badly exposed marly and calcareous dolomitic well-bedded strata followed by a thick calcareous bar. In section A, these materials (20 m) consist of massive white and yellowish limestone, micritic or finely intraclastic or bioclastic (packsto- nes), bearing some Foraminifera (Lituolidae)~ Bival- ves, Gastropods and Crustacean coprolites, while in the north, the equivalent rocks are formed by grey micrites to pelmicritic limestones, slightly dolomitized (25 m) with thin marly interbeds. Towards the top, the stratification becomes more differentiated and the limestones are marly micrites with frequent remains of Radiolaria, Porifera and Echinodermata (15 m in the northern sequence and 5 m in the southern). The marly interbeds are thicker and more frequent in the upper levels. In the southern part, the lower levels of this group are slightly brechified, probably because of their tectonic contact with the underlying massive

limestones, but laterally (on the opposite side of the river) the contact appears to be normal without brec- cia.

The section continues with thicker marls and marly limestones (35 m) alternating in the southern part, where some red and green nodular marly limestones strata are also interlayered. In the north, the thickness is only about 5 m.

The section B ends with several levels of red nodu- lar limestones (5 m) with a rather sharp contact with the underlying strata. By contrast, the southern sec- tion shows a gradual transition from the lower marly rocks to the upper pink and yellow nodular limesto- nes. The nodular micrites (7 m) with mainly Radiola- ria and Echinodermata remains are organized in well developed decimetric limestone strata, with thin red or yellow clay interbeds. The nodular character then peters out and grey and yellowish limestones (10 m) with Bivalvia, Brachiopoda and Crinoidea remains appear, some chert nodules are present in the upper levels.

Marly limestones are found overlying the former levels. The observable sequence ends with limestones with frequent chert nodules, in which Busnardo & alii (1966) cite some Domerian ammonites, overlain unconformably by the Upper Miocene of the Granada Basin.

FAUNAL ASSEMBLAGES

SECTION A (Southern) (fig. 2).

Detailed sampling allows us to establish the succes- sion of seven ammonite-assemblages.

1. Waehneroceras toxophorum (WAEHNER) (28 ex.), represented by small poorly preserved forms with rib- bing disappearing at the ventral edge at earlier onto- genetic stages than in the Waehner types (pl. 1, fig. 5).

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Waehneroceras sp. (6 ex.), represented by inner whorls with coiling, ornamentation and ventral region similar to the Waehener's ~ Aegoceras ~ extracosta- tum, considered by Elmi & Mouterde (1965) as synonymous of W. portlocki ( W R I G H T ) .

Alsatites sublaqueus (WAEHNER) (2 ex.), represen- ted by small and incomplete individuals (pl. 1, fig. 3).

2. A very poor assemblage consisting of Discamphice- ras kammerkarense (GUEMBEL) (1 ex.) and a single fragment of Alsatites sp. (pl. 1, fig. 6).

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SECTION A

Fig. 2 - - Stratlgraphical distribution of the ammonites in Section A.

Distribution stratigraphique des ammonites de la Coupe A.

3. A more diverse assemblage containing :

Vermiceras (Paracaloceras) coregonense (SOWERBY) (7 ex.) (pl. 1, fig. 1) recognizable by seve- ral incomplete small individuals and a complete one with the keel development ocurring at earlier stages

than in Waehner's forms. A specimen from the same level, with depressed whorls and clearly proradiate ribbing may correspond to Vermiceras (Paracaloce- ras) ligusticum (CANAVARI).

Vermiceras (Vermiceras) supraspiratum (WAEH- NER) (16 ex.) (pl. 1, fig. 7) represented by frequent small fragmentary remains. In this sample a strong ribbing density variation can be observed, with forms very close to V. (V.) praespiratissimum (WAEHNER).

Schlotheimia marmorea (OPPEL) (20 ex.) (pl. 1, fig. 10, 11) is the most frequent form of this association presenting an important variation, mainly in orna- mentation similar to that exhibited by Waehner's examples. In the upper level, together with finely rib- bed forms of this species, others small examples of Schlotheimia with stronger ornamentation and nearly subquadrate whorl section are found.

Typical forms of Kammerkaroceras emmrichi (GUEMBEL) (3 ex.) (pl. 1, fig. 8) are also present.

4. In this association some forms already quoted also appear : Schlotheimia marmorea (OPPEL) (3 ex.) and Vermiceras (Paracaloceras) coregonense (SOWERBY) (1 ex.) the last being similar to Waehner's A. aft. coregonensis (1886, pl. XXIV, fig. 10) in size, shape ornament and ventral features.

Schlotheimia cf. angulosa LANGE (2 ex.) (pl. 1, fig. 9) and body chamber fragments of Vermiceras (Para- caloceras) e u c e r a s (GUEMBEL) (2 ex.) were also found in this sample.

5. This is a relative poor assemblage containing only few examples of Tragolytoceras adnethicum (HAUER) (2 ex.) and Arnioceras mendax FUCINI (2 ex.) (pl. 1, fig. 14).

6. Arnioceras ceratitoides (QUENSTEDT) (22 ex.) (pl. 1, fig. 5) is the principal component of this assem- blage, represented by remains found in several beds. We attribute a certain polymorphism to this species, including variations in the whorl shape, ribbing den- sity and ventral features, where the well developed keel is flanked by smooth, more or less inclined tabula or even, by shallow sulci. This fauna is very similar to that described by Fucini (1902) but we do not restrict the term Arnioceras ceratitoides (QUENSTEDT) to Fucini's use of it, but we include : A. rejectum, A. semicostatum s e n s u F U C I N I , etc.

A single specimen of Hypasteroceras ? laevissimum (QUENSTEDT) (pl. 1, fig. 13) (= A. falcaries laevissi- mus), with ventral region and keel closer to Hypaste- roceras ceratiticum (FUcINI), is included in this asso- ciation. The Phylloceratina (7 ex.) are represented mostly by Geyeroceras cylindricum (SOWERBY).

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7. The last assemblage contains only Angulaticeras boucaultianum (D'ORamNY) (1 ex.) and Arnioceras ? sp. (1 ex.).

SECTION B (Northern) (fig. 3)

Only four poorer and less diverse assemblages can be recognized in this section.

1. This consists of inner whorls of Discamphiceras kammerkarense (GUEMaEL) (3 ex.) (pl. 1, fig. 2) and small and fragmentary remains, probably belonging to Waehnerocerasfrigga (WAEHNER) (3 ex.).

2. A large poorly preserved example of Waehneroce- ras megastoma (GUEMBEL) acompanied by a small incomplete Waehneroceras anisophyllum (WAEHNER) (pl. 1, fig. 4).

3. This asemblage consists of:Arnioceras mendax FUON~ (6 ex.), Tmaegoceras crassiceps (POMPECKJ) (3 ex.) (pl. 1, fig. 12), Sulciferites sp. (= Schlotheimia sp. FUCIN0 (3 ex.), Tragolytoceras adnethicum (HAUER) (2 ex.) and Geyeroceras cylindricum (SOWERBY) (3 ex.).

4. The youngest ammonites recorded in this section belong to Arnioceras ceratitoides (QUENST~DT) (7 ex,).

Fig. 3 - -

SECTION B

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Stratigraphical distribution of the ammonites in Section B.

Distribution stratigraphique des ammonites de la Coupe B.

BIOSTRATIGRAPHY AND CHRONOSTRATIGRAPHY

The palaeobiogeographic character of the recorded taxa compel us to refer the assemblages to the zonal division established in the alpine Hettangian (Waeh- ner, 1886 and Lange, 1952). There are no definitive occurences of index species of biostratigraphically significant taxa of the northwestern European (France, England and Germany) Zones.

Assemblages 1 and 2 of section A belong to Waeh- ner's Megastoma Zone and the 3rd and 4th to his Marmorea Zone. In section B, assemblages 1 and 2 also belong to Megastoma Zone and no forms inter- preted as belonging to the Marmorea Zone habe been collected.

The correlation between the alpine and northern european Hettangian zonal divisions is still unsolved. Dean & alii (1961) correlate Waehner's and Lange's (1952) Megastoma Zone with the Portlocki Subzone. Elmi & Mouterde (1965) considering that the greatest abundance of Waehneroceras occurs in both zones correlate the Portlocki with the Megastoma Zone. In

Lange's opinion, the Megastoma Zone is equivalent to ~ ld, *< le and o< lf, corresponding to Elmi & Mouterde's Portlocki and Liasicus Zones.

In general, a correlation between the Marmorea and Angulata Zones can be made, but there is a great deal of imprecision in the correlation of the limits, on one hand, because of the virtual absence of common taxa and, on the other, by the fact that the limits of Mar- morea Zone have not yet been well defined.

The presence of Schlotheimia cf. angulosa suggests that assemblage 4 corresponds to the upper part of the Angulata zone (= e~ 2c, = Lange's Stenorhynchia level).

The absence of any indices of the beginning of the Sinemurian, and Dean & alii's opinion that Schlothei- mia marmorea << is not confined to the Angulata Zone )> make it impossible to define precisely the upper limit in the Hettangian in the Betic Cordillera.

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No Zonal division exists in the alpine- mediterranean Sinemurian. There are some fossils quoted in the north-european zones in assemblages 5 and 6 of section A and in the 3rd of section B, but no index fossils of those biostratigraphic units have been collected and biostratigraphic and chronostratigra- phic correlation of our assemblages with any of the usual zonal units is rather imprecise.

Guerin-Franiatte (1966) found Arnioceras mendax in the French Semicostatum Zone (CSte-d'Or and RhSne). Tmaeogoceras crassiceps, associated with the former, is situated by Gebhard & Schlatter (1977) at the limit of the Bucklandi and Semicostatum Zone in Engslatt. Therefore, assemblages 5 of the section A and 3 of the section B may correspond to the lower part of Semicostatum Zone.

Mouterde (1953) established Arnioceras ceratitoides as an index fossil of a biostratigraphic level that Dean & alii (1961) correlate with the Reynesi Subzone (= Guerin-Franiatte's Lyra Zubzone). Blind (1963) found Arnioceras ceratitoides widely spread throug- hout most of the Sinemurian and part of the Lotha- ringian. The first appearance of the species in the Breitenberg section is immediately after Coroniceras rotiforme, and the last associated with Asteroceras species of evident Lotharingian age.

It is still impossible to correlate assemblage 6 of sec- tion A and assemblage 4 of section B, with mainly comprise Arnioceras ceratitoides with a precise bios- tratigraphic unit. Angulaticeras boucaultianum, the only species found in assemblage 7 is known to have a wide biostratigraphic range, but is more frequently reported in the Lotharingian.

SOME PALAEOBIOGEOGRAPHICAL CONSIDERATIONS

The ammonite fauna found are clearly mediterra- nean in character. Although most of the genera pre- sent are not palaeobiogeographically restricted, the species are known mainly in the Alpine, North Afri- can and Italian sequences. The faunal character and the scanty knowledge of the Lower Liassic mediterra- nean biostratigraphy limit correlation with the nor- thern european zonal divisions, and an accurate chro- nostratigraphical evaluation of our assemblages.

The fauna present some remarkable characteris- tics : - The absolute dominance of mediterranean Waehne- roceras in all the Middle Hettangian. - The abundance of Vermiceras in the Upper Hettan- gian assemblages. - The absence of characteristics faunas of the lower part of the Sinemurian.

- The almost absolute predominance of Arnioceras in the Sinemurian (s. str.) and the rare occurrence of Tmaegoceras.

The mediterranean character of the Hettangian fauna containing ammonite species practically unk- nown outside the Alpine area, and with absence of species of the northeuropean province lead us to con- sider the studied section as a reference section for the west mediterranenan Hettangian.

Some of the species found in our assemblages (W. anysophyllum, A. ceratitoides, A. rejectum) have been also cited in the northafrican << Dorsalian Series >>. (Mouterde, 1968, Olivier & Mouterde, 1979 considering only figurated forms).

Acknowledgements

We want to thank D. Butler M.A. (Oxon), of the Medical Faculty of the University of Granada, and M. Phelps for the

English text of this study, and Prof. A. Linares, S. Elmi and R. Mouterde for the critical reading of the manuscript.

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R E F E R E N C E S

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VIENNOT P. (1930) - Observations g6ologiques dans la r~gions de Grenade (Andalousie). Livre Jubilaire Soc. gEoL France, Paris, t. II, p. 632-660, 11 fig., pl. LIV.

WAEHNER F. (1886-1888) - Beitrage zur Kenntiss der tiere- feren Zonen des Unteren Lias in den NordOstlichen Alpen. Beitr. z. Palllont. Osterreichs-Ungarns, Wien, vol. IV, fasc. 3-4, p. 135-226, pl. XV-XXX ; vol. VI (1888), p. 241-268.

Manusc r i t d6f in i t i f r ~ u le 07.02.1984

PLATE

P L A T E 1

Fig. 1 --Vermiceras (Paracaloceras) coregonense (SOWERBY). Assemblage 3, Section A. (x 2/3). Upper Hettangian (For D=126 ; o=71,807o ; h= 16,707o ; e= 15,107o).

Fig. 2--Discamphiceras kammerkarense (GUEMBEL). Assemblage 1, Section B. Middle Hettangian.

Fig. 3--Alsatites sublaqueus (WAEHNER). Assemblage 1, Section A. Middle Hettangian (For D = 4 4 : o=61,407o ; h=22,707o ; e=26,607o).

Fig. 4--Waehneroceras anisophyllum (WAEHNER). Assemblage 2, Section B. Middle Hettangian (For D=39,5 : o=43,007o ; h=30,407o).

Fig. 5 --Waehneroceras toxophorum (WAEHNER). Assemblage 1, Section A. Middle Hettangian (For D = 39,5 : o = 31,607o ; h=40,507o ; e=26,607o).

Fig. 6 --Alsatites sp. Assemblage 2, Section B.Middle Hettangian (For D=33 : o=66,7% ; h=21,207o ; e=24,207o).

Fig. 7--Vermiceras (Vermiceras) supraspiratum (WAEHNER). Assemblage 3, Section A. Upper Hettangian. (For D = 30 : o = 70,7% ; h = 16,7o7o ; e = 2007o).

Fig. 8 --Kammerkaroceras emmrichi (GUEMBEL). Assemblage 3, Section A. Upper Hettangian.

Fig. 9--Schlotheimia ef. angulosa LANGE. Assemblage 4, Section A. Upper Hettangian (For D=39:o=41,007o ; h= 33,307o ; e=28,207o).

Fig. 10 --Schlotheimla marmorea (OPPEL). Assemblage 3, Section A. Upper Hettangian (For D = 30 : o = 31,707o ; h = 40070 ; e = 22,307o).

Fig. 11 - -Schlo the imia m a r m o r e a (OPPEL). A s s e m b l a g e 3, Sec t ion A. U p p e r H e t t a n g i a n (For D=23 : 0=30,407o ; h=43,507o ; e=26.907o).

Fig. 12 --Tmaegoceras crassiceps (POMPECKJ). Assemblage 3, Section B. Sinemurian (ventro-lateral view).

Fig. 13 --Hypasteroceras ? laevissimum (QUENSTEDT). Assemblage 6, Section A. Sinemudan (For D = 2 8 : 0=42,907o ; h = 28,6°7o ; e = 21,407o).

Fig. 14--Arnioceras mendax FUCINI. Assemblage 5, Section A. Sinemudan (For D=78,5 : 0=59,9°7o ; h=20,407o ; e = 20,407o).

Fig. 15--Arnloceras ceratitoides (QUENSTEDT). Assemblage 6, Section A. Sinemurian (For D=48,5:o=49,507o ; h = 29,9070). '

Note : All the specimens (except fig. 1) are reproduced to 0,95 of the natural size. The samples are deposited in the Museum of Departamento de Paleontologia, Universidad de Granada.

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