Antunes, M. Telles

English

New University of Lisbon's Repository

Contributions to the Eocene palaeontology and
stratigraphy ofBeira Alta, Portugal
I -A Synoptical table
M. T. ANTUNES *t
.. Academia das Cicncias de Lisboa
tCentro de Estratigrafia e Paleobiologia da UNL, Faculdade de Ciencias e Tecnologia,
Quinta da Torre, P-2825 Monte da Caparica, Portugal
Ciencias da Terra (UNL) Lisboa pp.77-81 1992

The sedimentary units on the very extensive
erosion platforms that cut nearly all relief of the
hercynian basement in Beira Alta province, Portugal,
were poorly known. This applies both to stratigraphy
and age, since no detailed field studies were carried
on and no fossils had been found. Facies similarities
led to some hypotheses without adequate support.
Correlations had sometimes been proposed between
earlier deposits and late Cretaceous sediments close
by (or within) the western meso-cenozoic basins,
whereas younger beds were more or less classified
according to geomorphological criteria.
Classification has not yet been fully attained.
However research is in progress since the first contri-
bution concerning the Coja site (1953) and the first
upper Eocene dating (1964).
Near half a century of research seem to justify
the presentation of a short synthesis as contained in
the following Synoptical Table.
Upper Eocene sites at Beira Alta - Synoptical
table
1953
(or somewhat earlier, as far as findings are concerned):
- Fossil bones are found at the Empresa Ceramica da
Carrica Lda. clay quarry near Coja.
- Mr. J. de Castro Nunes, then in charge of the
Arganil Museum, gives notice of these findings to the
Director of the Services Geol6gicos de Portugal, A. de
Castello Branco, who in turn informs G. Zbyszewski.
- Arganil Museum and the Coja quarry are visited
by Professors C. Teixeira and D. Thadeu; an account is
published by Castro Nunes (local newspaper"A Comarea
de Arganil", Aug.l3).
- Bones are sent by Castro Nunes through D. Thadeu
to G.Zbyszewski, who publishes a note (ZBYSZEWSKI,
1953) where he ascribed some specimens to a "Cervide de
la taille d'un Cerf elaphe" but cannot decide whether "il
sagit de Cervides tertiaires ou quaternaires" (ibid.• pp.59-
60); however, molar structure was clearly that of a
Perissodactyl, and even if it was indeed a Cervid, its rather
large size would certainly point out to (at least) a post-
middle Miocene age; a brief geological description is
given.
1956:
- geologist P.Martins de Carvalho, who was doing
field work for the Empresa de Ceramica da Carrica Lda.
collected (or otherwise was given) some further bones that
he sent to Professor M. Montenegro de Andrade at the
Universidade de Coimbra.
1959:
- (June-July) field work at the same area around
Coja was carried on by J.Oliveira (technician, Services
Geol6gicos de Portugal); a geological sketch was produced
but never published.
1963:
- Comparison with stratigraphic evidence from
Eocene beds between Zamora and Salamanca in Spain
suggested M.T.Antunes to review the mammalian rem-
nants from Coja: after comparative work at the Museum
National d'HistoireNaturelle, Paris, where type specimens
from Paris basin were observed, a Palaeotherium cf.
crassum and thus a near certain Ludian (upperEocene) age
are recognized; for the first time an Eocene age was
demonstrated in Portugal (ANTUNES, 1963).
1964:
- (April) M.T'Antunes, while trying to collect more
fossils at the same site, was given a mammalian
hemimandible found in a clay prospection pit.
-(August) M.T.Antunes works at EmpresaCeramica
da Carrica Lda. quarry in order to get more detailed
stratigraphic data, to locate the level(s) where fossils had
been found and to excavate the fossiliferous beds; a max-
illary from a small mammal is found along with scant bone
fragments, in about 4 cubic meters of sediment, but wash-
ing and sieving at the site failed to produce positive results.
- (November) M.T.Antunes tries again but only
finds a poorly preserved bone fragment, the last fossil that
seems to have been collected there.
1965:
previous results are taken into account by
ZBYSZEWSKI (1965), who discusses in general their
stratigraphic meaning; converging with viewpoints previ-
79
ously held in Portugal (where most pre-Miocene continen-
tal sediments wereregarded withoutanyproofas Oligocene),
our 1963 conclusions are distorted as the Ludian age, even
if ackonwledged, was considered by him as lowermost
Oligocene.
1967:
- (October): complementary field data are obtained
and a detailed stratigraphic section is studied by
M.T.Antunes.
- in another paper (ANTUNES, 1967) a detailed
lithostratigraphic account is given; local units were charac-
terized and among them a "Coja Group" that comprises
what was later called "Arcoses de Coja" Formation, this
being clearly recognizable; two new mammalian taxa are
identified, Peratherium cf. cuvieri and Diplobune
secundaria; Coja fauna is accurately reported to higher
levels in the Ludian, uppermost Eocene, like the well-
known fauna from the "haute masse" from the Paris Gyp-
sum; Eocene-Oligocene limits are discussed, and the rela-
tionships with Pyrenean orogeny are shown.
1972:
- taking into account our previous results, J.
JIMENEZ-FUENTES (Studia Geologica. III, pp.l06-107,
Salamanca) presents a correlation attempt between
portuguese eocene (and maybe older) units North of the
Central Chain and others between Zamora and Salamanca.
1973:
- Mr. A.Brum Ferreira visits another clay exploita-
tion at Naia, between Canas de Sabugosa and Tondela
(Ceramica da Beira, Lda.), some 30 km North of Coja,
where he is told of findings of fossils; he passes this
information to A.M.Galopim de Carvalho, who in turn
averts M.T.Antunes.
- (September): Carvalho and Antunes were shown
by Mr. Alvaro Fernandes (quarry manager) the Naia ex-
ploitation, where a bone (tentatively ascribed by Antunes to
a humerus ofaPalaeotherium) was exposed; a stratigraphic
section was summarily sketched by Antunes, showing
above the granite substractum (a) a lower unit ofconglom-
erates, sands and clays, more or less carbonaceous and
grey-coloured, with trunks, (b) apparently separated by an
unconformity, an upper unit of greenish, arkosic clays with
white bones.
1974:
- (June): field work proceeds at Naia; another sec-
tion shown by A.Fernandes is studied at a nearby point
named Cabecinhas, exposing particularly well the lower,
carbonaceous unit; sediment samples are taken and yield
some pollen and spores (J.Pais); a fragment of coaly trunk
from a tree fern from the same unit is given by the Director
of Ceramica da Beira, Lda.
1975:
- (February or March): remains from a tortoise are
found at Naia by A.Fernandes.
- (September): A.Fernandes presents M.T.Antunes
with the tortoise bones he collected, and shows a new clay
exploitation at Bairro das Cumieiras, NW Tondela; both
the lower carbonaceous and the upper greenish units are
exposed.
in a paper on a new eocene crocodilian,
Iberosuchus, ANTUNES (Comunic. Servo Geol. Port .•
LIX, pp.315-317) gives a synthesis on eocene Formations
80
in Portugal and western Spain and respective correlations;
the"Arkoses et argiles fossiliferes de Coja, Naia, Nave de
Haver, etc." are separated from other units and reported to
the Ludian.
1976:
- (June): field work is resumed (M.T.Antunes,
A.Brum Ferreira and J.Pais) with a revision of the
stratigraphic sections at Coja and Naia (atCabecinhas, new
carbonaceous clays samples arecollectedfor palynological
study) and new observations at Barreiro de Besteiros near
Tondela.
1977:
- a study on the Naia tortoise is published
(ANTUNES & DE BROIN, see References) along with a
geologic introduction; the presence of ?Cheirogaster sp.
affords a chronological element as it indicates a pre-Upper
Oligocene and po.st-Middle Eocene age; correlation be-
tween greenish, arkosic clays from Naia and Coja is con-
firmed, and definitely not based on lithological similarity
only.
1978:
- in his thesis on the revision of the tertiary marsu-
pials from Europe, J.Y.CROCHET reports without any
doubt the Coja one to Peratherium cuvieri; a memoir is
published - 1980, Les Marsupiaux du Tertiaire d' Europe.
Edit. Fondation Singer-Polignac, Paris, see pp.198 and
248; hence this marsupial became an additional evidence
for a Ludian age (levels 2 to 5; cf. D.E.RUSSELL et al.,
pp.41-43 - see References).
- in an extensive study of erosion surfaces in the
Northern part ofBeira region (A.B.FERREIRA,MemOrias
do Centro de Estudos Geogrdficos, n1l4, Lisboa; see pp.38-
39, 200-201, 296-297), the fauna from Coja appears as a
key chronological reference, providing some basis for
correlations with surfaces and overlying sedimentary units
in western Spain.
1979:
-M.T. ANTUNES (Ciencias da Terra (UNL),
Lisboa, n25; see pp.161-162) presents a synthesis on the
sedimentary units that overlie granites and other basement
rocks in the Beira Alta province; the "Arenitos deCoja" are
dealt with again.
1983:
A.F.SOARES, R.P.REIS & S. DAVEAU
(Mem6riaseNot(cias.Publ.Mus.Lab.Mineral.Geol.,Univ.
Coimbra, n096; cf. pp.12-16) attempt to correlate
Iithostratigraphic units from basins on the basement(Lousa,
Arganil) to those from the western basin, onolderMesozoic;
the Coja unit with Ludian fauna (referred to as "Arcoses de
Coja") correlations are not clearly established.
1984:
- M.T.ANTUNES, who in the previous years car-
ried on prospection for fossils, is averted by Ing. Almiro,
Director of Cerarnica da Beira, L.da, of the discovery of a
fossil trunk in the lower unit (carbonaceous clays). In
September, the site is visited by Antunes, J.C. Pais and C.
Estravis; samples are collected.
1985:
- geomorphologic and sedimentological studies on
the Lousa and Arganil basins are published (S.DAVEAU et
al., Memorias do Centro de Estudos Geogrdficos, n28,
Lisboa; see p.167), the importance of the Coja site being
stressed.
1986:
- previous recuperation of a few long forgotten
specimens, without any label or other reference but from
the first (1953) Coja collection, allows ANTUNES (see
References) to recognize two new taxa: a tortoise,
Geochelone (s.gen.) sp., possibly the same as the
Geochelone (?Cheirogaster) sp. from Naia; and
Anoplotherium cf. commune.. the Coja fauna is now more
accurately reported to the level 4 (Montmartre) of the
Ludian.
1988:
- (December): Mr. PProenca e Cunha finds the
bone fragments collected at Coja in 1956 and subsequently
sends them to Antunes.
1990:
- (January): Antunes studies the 1956 collection at
the Paris Museum, and prepares the account published
here.
81


Contributions to the Eocene palaeontology and stratigraphy of Beira Alta, Portugal I -A Synoptical table

Repositório da Universidade Nova de Lisboa

Contributions to the Eocene palaeontology andstratigraphy ofBeira Alta, PortugalI -A Synoptical tableM. T. ANTUNES *t.. Academia das Cicncias de LisboatCentro de Estratigrafia e Paleobiologia da UNL, Faculdade de Ciencias e Tecnologia,Quinta da Torre, P-2825 Monte da Caparica, PortugalCiencias da Terra (UNL) Lisboa pp.77-81 1992The sedimentary units on the very extensiveerosion platforms that cut nearly all relief of thehercynian basement in Beira Alta province, Portugal,were poorly known. This applies both to stratigraphyand age, since no detailed field studies were carriedon and no fossils had been found. Facies similaritiesled to some hypotheses without adequate support.Correlations had sometimes been proposed betweenearlier deposits and late Cretaceous sediments closeby (or within) the western meso-cenozoic basins,whereas younger beds were more or less classifiedaccording to geomorphological criteria.Classification has not yet been fully attained.However research is in progress since the first contri-bution concerning the Coja site (1953) and the firstupper Eocene dating (1964).Near half a century of research seem to justifythe presentation of a short synthesis as contained inthe following Synoptical Table.Upper Eocene sites at Beira Alta - Synopticaltable1953(or somewhat earlier, as far as findings are concerned):- Fossil bones are found at the Empresa Ceramica daCarrica Lda. clay quarry near Coja.- Mr. J. de Castro Nunes, then in charge of theArganil Museum, gives notice of these findings to theDirector of the Services Geol6gicos de Portugal, A. deCastello Branco, who in turn informs G. Zbyszewski.- Arganil Museum and the Coja quarry are visitedby Professors C. Teixeira and D. Thadeu; an account ispublished by Castro Nunes (local newspaper"A Comareade Arganil", Aug.l3).- Bones are sent by Castro Nunes through D. Thadeuto G.Zbyszewski, who publishes a note (ZBYSZEWSKI,1953) where he ascribed some specimens to a "Cervide dela taille d'un Cerf elaphe" but cannot decide whether "ilsagit de Cervides tertiaires ou quaternaires" (ibid.• pp.59-60); however, molar structure was clearly that of aPerissodactyl, and even if it was indeed a Cervid, its ratherlarge size would certainly point out to (at least) a post-middle Miocene age; a brief geological description isgiven.1956:- geologist P.Martins de Carvalho, who was doingfield work for the Empresa de Ceramica da Carrica Lda.collected (or otherwise was given) some further bones thathe sent to Professor M. Montenegro de Andrade at theUniversidade de Coimbra.1959:- (June-July) field work at the same area aroundCoja was carried on by J.Oliveira (technician, ServicesGeol6gicos de Portugal); a geological sketch was producedbut never published.1963:- Comparison with stratigraphic evidence fromEocene beds between Zamora and Salamanca in Spainsuggested M.T.Antunes to review the mammalian rem-nants from Coja: after comparative work at the MuseumNational d'HistoireNaturelle, Paris, where type specimensfrom Paris basin were observed, a Palaeotherium cf.crassum and thus a near certain Ludian (upperEocene) ageare recognized; for the first time an Eocene age wasdemonstrated in Portugal (ANTUNES, 1963).1964:- (April) M.T'Antunes, while trying to collect morefossils at the same site, was given a mammalianhemimandible found in a clay prospection pit.-(August) M.T.Antunes works at EmpresaCeramicada Carrica Lda. quarry in order to get more detailedstratigraphic data, to locate the level(s) where fossils hadbeen found and to excavate the fossiliferous beds; a max-illary from a small mammal is found along with scant bonefragments, in about 4 cubic meters of sediment, but wash-ing and sieving at the site failed to produce positive results.- (November) M.T.Antunes tries again but onlyfinds a poorly preserved bone fragment, the last fossil thatseems to have been collected there.1965:previous results are taken into account byZBYSZEWSKI (1965), who discusses in general theirstratigraphic meaning; converging with viewpoints previ-79ously held in Portugal (where most pre-Miocene continen-tal sediments wereregarded withoutanyproofas Oligocene),our 1963 conclusions are distorted as the Ludian age, evenif ackonwledged, was considered by him as lowermostOligocene.1967:- (October): complementary field data are obtainedand a detailed stratigraphic section is studied byM.T.Antunes.- in another paper (ANTUNES, 1967) a detailedlithostratigraphic account is given; local units were charac-terized and among them a "Coja Group" that compriseswhat was later called "Arcoses de Coja" Formation, thisbeing clearly recognizable; two new mammalian taxa areidentified, Peratherium cf. cuvieri and Diplobunesecundaria; Coja fauna is accurately reported to higherlevels in the Ludian, uppermost Eocene, like the well-known fauna from the "haute masse" from the Paris Gyp-sum; Eocene-Oligocene limits are discussed, and the rela-tionships with Pyrenean orogeny are shown.1972:- taking into account our previous results, J.JIMENEZ-FUENTES (Studia Geologica. III, pp.l06-107,Salamanca) presents a correlation attempt betweenportuguese eocene (and maybe older) units North of theCentral Chain and others between Zamora and Salamanca.1973:- Mr. A.Brum Ferreira visits another clay exploita-tion at Naia, between Canas de Sabugosa and Tondela(Ceramica da Beira, Lda.), some 30 km North of Coja,where he is told of findings of fossils; he passes thisinformation to A.M.Galopim de Carvalho, who in turnaverts M.T.Antunes.- (September): Carvalho and Antunes were shownby Mr. Alvaro Fernandes (quarry manager) the Naia ex-ploitation, where a bone (tentatively ascribed by Antunes toa humerus ofaPalaeotherium) was exposed; a stratigraphicsection was summarily sketched by Antunes, showingabove the granite substractum (a) a lower unit ofconglom-erates, sands and clays, more or less carbonaceous andgrey-coloured, with trunks, (b) apparently separated by anunconformity, an upper unit of greenish, arkosic clays withwhite bones.1974:- (June): field work proceeds at Naia; another sec-tion shown by A.Fernandes is studied at a nearby pointnamed Cabecinhas, exposing particularly well the lower,carbonaceous unit; sediment samples are taken and yieldsome pollen and spores (J.Pais); a fragment of coaly trunkfrom a tree fern from the same unit is given by the Directorof Ceramica da Beira, Lda.1975:- (February or March): remains from a tortoise arefound at Naia by A.Fernandes.- (September): A.Fernandes presents M.T.Antuneswith the tortoise bones he collected, and shows a new clayexploitation at Bairro das Cumieiras, NW Tondela; boththe lower carbonaceous and the upper greenish units areexposed.in a paper on a new eocene crocodilian,Iberosuchus, ANTUNES (Comunic. Servo Geol. Port .•LIX, pp.315-317) gives a synthesis on eocene Formations80in Portugal and western Spain and respective correlations;the"Arkoses et argiles fossiliferes de Coja, Naia, Nave deHaver, etc." are separated from other units and reported tothe Ludian.1976:- (June): field work is resumed (M.T.Antunes,A.Brum Ferreira and J.Pais) with a revision of thestratigraphic sections at Coja and Naia (atCabecinhas, newcarbonaceous clays samples arecollectedfor palynologicalstudy) and new observations at Barreiro de Besteiros nearTondela.1977:- a study on the Naia tortoise is published(ANTUNES & DE BROIN, see References) along with ageologic introduction; the presence of ?Cheirogaster sp.affords a chronological element as it indicates a pre-UpperOligocene and po.st-Middle Eocene age; correlation be-tween greenish, arkosic clays from Naia and Coja is con-firmed, and definitely not based on lithological similarityonly.1978:- in his thesis on the revision of the tertiary marsu-pials from Europe, J.Y.CROCHET reports without anydoubt the Coja one to Peratherium cuvieri; a memoir ispublished - 1980, Les Marsupiaux du Tertiaire d' Europe.Edit. Fondation Singer-Polignac, Paris, see pp.198 and248; hence this marsupial became an additional evidencefor a Ludian age (levels 2 to 5; cf. D.E.RUSSELL et al.,pp.41-43 - see References).- in an extensive study of erosion surfaces in theNorthern part ofBeira region (A.B.FERREIRA,MemOriasdo Centro de Estudos Geogrdficos, n1l4, Lisboa; see pp.38-39, 200-201, 296-297), the fauna from Coja appears as akey chronological reference, providing some basis forcorrelations with surfaces and overlying sedimentary unitsin western Spain.1979:-M.T. ANTUNES (Ciencias da Terra (UNL),Lisboa, n25; see pp.161-162) presents a synthesis on thesedimentary units that overlie granites and other basementrocks in the Beira Alta province; the "Arenitos deCoja" aredealt with again.1983:A.F.SOARES, R.P.REIS & S. DAVEAU(Mem6riaseNot(cias.Publ.Mus.Lab.Mineral.Geol.,Univ.Coimbra, n096; cf. pp.12-16) attempt to correlateIithostratigraphic units from basins on the basement(Lousa,Arganil) to those from the western basin, onolderMesozoic;the Coja unit with Ludian fauna (referred to as "Arcoses deCoja") correlations are not clearly established.1984:- M.T.ANTUNES, who in the previous years car-ried on prospection for fossils, is averted by Ing. Almiro,Director of Cerarnica da Beira, L.da, of the discovery of afossil trunk in the lower unit (carbonaceous clays). InSeptember, the site is visited by Antunes, J.C. Pais and C.Estravis; samples are collected.1985:- geomorphologic and sedimentological studies onthe Lousa and Arganil basins are published (S.DAVEAU etal., Memorias do Centro de Estudos Geogrdficos, n28,Lisboa; see p.167), the importance of the Coja site beingstressed.1986:- previous recuperation of a few long forgottenspecimens, without any label or other reference but fromthe first (1953) Coja collection, allows ANTUNES (seeReferences) to recognize two new taxa: a tortoise,Geochelone (s.gen.) sp., possibly the same as theGeochelone (?Cheirogaster) sp. from Naia; andAnoplotherium cf. commune.. the Coja fauna is now moreaccurately reported to the level 4 (Montmartre) of theLudian.1988:- (December): Mr. PProenca e Cunha finds thebone fragments collected at Coja in 1956 and subsequentlysends them to Antunes.1990:- (January): Antunes studies the 1956 collection atthe Paris Museum, and prepares the account publishedhere.81

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Contributions to the Eocene palaeontology and stratigraphy of Beira Alta, Portugal I -A Synoptical table

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