GeolCarp_Vol64_No6_499

www.geologicacarpathica.sk

GEOLOGICA CARPATHICA

, DECEMBER 2013, 64, 6, 499—501 doi: 10.2478/geoca-2013-0035

Reply to the Comment of A. Pszczółkowski on “Calpionellid

distribution and microfacies across the Jurassic/Cretaceous

boundary in western Cuba (Sierra de los Órganos)” by

López-Martínez et al. (2013)

RAFAEL LÓPEZ-MARTÍNEZ

, RICARDO BARRAGÁN

, DANIELA REHÁKOVÁ

and

JORGE L. COBIELLA-REGUERA

Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Delegación Coyoacán, C.P. 04510 México D.F.,

México; rafaelopez83@hotmail.com

Comenius University, Faculty of Natural Sciences, Department of Geology and Paleontology, Mlynská dolina G, 842 15 Bratislava,

Slovak Republic; rehakova@fns.uniba.sk

Departamento de Geología, Universidad de Pinar del Río, Martí 270, Pinar del Río, C.P. 20100, Cuba

Introduction

Discussions about the Jurassic/Cretaceous boundary in Cuba
are welcome and expected. We are grateful to A. Pszczółkowski
for his interesting comment on our work. Our paper focuses
on the calpionellid biostratigraphy and facies distribution to
establish  the  Jurassic/Cretaceous  boundary  in  a  “specific”
section  of  the  Guasasa  Formation  named  the  San  Vicente
section.  Unfortunately,  the  comment  by  A.  Pszczółkowski
included  no  special  mentions  of  the  main  objectives  of  our
publication. Comments are mainly stressed out around some
minor  discrepancies  of  the  results  of  our  contribution  with
those previously published by the aforementioned author.

Reply to individual points of the comment

… the authors have omitted some important features … In
the type section, the El Americano Member deposits were
described as dark-grey to black limestones with ammonites
(Houša & Nuez 1972).

As Pszczółkowski (2013) clearly explains, no more detailed

description  of  the  unit  was  made  in  López-Martínez  et  al.
(2013), due to the fact that earlier works characterized the El
Americano  Member  (Houša  &  Nuez  1972;  Pszczółkowski
1978;  Myczyński  &  Pszczółkowski  1990;  Pszczółkowski
1999;  Cobiella-Reguera  &  Olóriz  2009;  Pszczółkowski  &
Myczyński  2010;  Iturralde-Vinent  &  Pszczółkowski  2011).
Nonetheless,  the  description  in  López-Martínez  et  al.  (2013)
took into account all the necessary aspects for its recognition,
including  the  presence  of  ammonites  and  calpionellids;  only
the attribute “dark-grey to black limestones” was not specified.

… should not be restricted to the Rancho San Vicente sec-
tion, as it presents the stratigraphic position of the Guani-
guanico units in general, in the Los Órganos and Rosario
successions.

The lithostratigraphic units of the Rancho San Vicente

section  are  part  of  the  Guaniguanico  units.  If  Figure 2  by
Pszczółkowski  &  Myczyński  (2010)  represents  the  strati-
graphic position of the Guaniguanico units, it is hard to con-
ceive  how  it  does  not  include  that  section.  Thus,  the
stratigraphy of the Rancho San Vicente would be embraced
by  the  stratigraphic  framework  of  the  Guaniguanico  mega-
unit as a whole.

The authors do not mention, that at San Vicente the age …
was identified by Pop (1976, fig. 4) as Late Tithonian
(

Crassicollaria Zone). Therefore, the Late Tithonian age of

the boundary between the San Vicente and El Americano
members in the San Vicente section was known after 1976.

López-Martínez et al. (2013), described the San Vicente

Member as follows: “… This unit is of Kimmeridgian—Early
Tithonian  age  according  to  Pszczółkowski  &  Myczyński
(2010)”.  Then,  the  overlying  El  Americano  Member  has  to
be  Late  Tithonian  for  the  Steno  principle  since  no  a  hiatus
was  identified.  Moreover,  the  Tumbadero  Member  was  de-
scribed as: “Middle—Late Berriasian age with very thin cherty
beds  and  lenses”.  Therefore,  the  El  Americano  Member,
spanning from the end of the San Vicente Member to the be-
ginning  of  the  Tumbadero  Member,  has  to  span  from  the
Late Tithonian to the Early Berriasian.

On the other hand, although stressed by Pszczółkowski in

his comment, the fact that the Late Tithonian age of the

DISCUSSION – REPLY

(Manuscript received October 24, 2013)

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LÓPEZ-MARTÍNEZ, BARRAGÁN, REHÁKOVÁ and COBIELLA-REGUERA

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 6, 499—501

boundary between the San Vicente and El Americano mem-
bers in the San Vicente section was known from Pop (1976),
it seems not to be accepted by Pszczółkowski & Myczyński
(2010). On figures 2, 3, 5b and 20 of that work, such contact
is  placed  as  Kimmeridgian—Tithonian.  Furthermore,  on
page 228,  they  explain  “The  ?Late  Oxfordian—Kimmeridgian
age of the San Vicente Member was defined on the basis of its
lithostratigraphic  position  between  ammonite-bearing  units
and scarce pelagic microfossils found in the limestones of this
Member”. Also, on page 235 they explain “The San Vicente/
El  Americano  Members  boundary  correlates  approximately
with  the  Kimmeridgian/Tithonian  boundary,  at  the  base  of
the Hybonoticeras-Mazapilites Zone (Fig. 2)”.

Despite previous discussion, in our work we refine the

biostratigraphy  of  the  San  Vicente  section.  The  age  of  the
basal  stratum  of  the  El  Americano  Member  is  clearly  late-
Early Tithonian (sensu Jach et al. 2012), Chitinoidella Zone
(Boneti  Subzone)  which  was  previously  designated  as  the
Crassicollaria Zone (sensu Pop 1976).

… “in more detailed work it is possible to find a diachro-
nism in the appearance of pelagic conditions” (and so on)
is true, but not new (please see Pop 1976 and
Pszczółkowski 1978, 1981).

The new data on the age of the San Vicente Member in the

“San Vicente section” in our study, place the contact San Vi-
cente/El Americano in the late—Early Tithonian (Boneti Sub-
zone). This datum applies solely to the studied section, and
not  to  the  whole  Sierra  de  los  Órganos  as,  according  to
Pszczółkowski  (2013,  his  comment),  we  pretend  to  affirm.
Thus,  regardless  of  “how  new”  the  idea  of  the  diachronism
of pelagic conditions is in the whole Sierra de los Órganos,
the  age  datum  is  new  for  the  San  Vicente  section  since  it
contradicts previous works (i.e. Pszczółkowski & Myczyński
2010),  refining  and  bringing  up  to  date  its  biostratigraphic
framework.

… Originally, the figured juvenile gastropods were found
in other sections of the Guaniguanico megaunit; their oc-
currence was interpreted in terms of moderate to poor oxy-
gen levels at the sediment-water interface.

Gastropods in the San Vicente section are taken into con-

sideration separately in another paper about the Taphonomy
of the section and which is now in press. Nonetheless, the
explanation of the juvenile gastropods in Pszczółkowski &
Myczyński (2010) is ambiguous, because their data are con-
tradictory to their conclusion.

On page 233, those authors explain: “Juvenile gastropods

(Ampullospiridae, mainly Globularia spp., and Pleurotomar-
iidae) co-occur with dark-brown to black faecal pellets. The
presence of Globularia-dominated minute (juvenile) gastro-
pods and lack, or extreme scarcity, of adults in the Lower Ti-
thonian limestones suggest an unfavourable environment for
these molluscs. Low oxygenation levels are a reasonable ex-
planation for this type of micro-gastropod assemblage”.

On page 235 of the same publication: “3.2. Facies type 2:

Bioclastic to shelly limestones (coquinas) and Breccias. This

facies type is represented by dark-grey to black bioclastic and
shelly limestones (Fig. 16) composed of ammonites, aptychi,
juvenile gastropods and, sometimes, phosphatic (sh) detritus
(Fig. 14.4). Juvenile ammonites occur in thin micritic inter-
calations  occasionally  preserved  in  ammonite  coquinas
(Fig. 14.5  and  Fig. 17.3—4)”;  “Current  imbrication  was
observed in an aptychi coquina; origin of bioclastic and shelly
interbeds was related to episodic high-energy events, probably
caused by heavy storms and/or stronger paleocurrent activity”;
“3.3. Facies type 3: Pelagic biomicrites with occasional cal-
carenite  interbeds. … Juvenile  ammonites  (Figs. 14.6  and
17.4)  and  gastropods  (Fig. 15.1—3)  often  occur  in  these
biomicrites”; “Calcarenite interbeds composed mainly of the
shallow-water constituents (ooids, bioclasts, Favreina copro-
lites, etc.) have been reported from the Late Tithonian—Early
Berriasian  strata  of  the  Southern  Rosario  succession
(Pszczółkowski  1978).  These  interbeds,  0.2—10 m  thick  in
various sections, were interpreted as calciturbidites, mainly”.

On page 236: “Drowning of the Kimmeridgian carbonate

banks of the Sierra de los Organos and Northern Rosario oc-
curred during the Kimmeridgian/Tithonian boundary interval,
although shallow-water bioclasts and coated grains were inter-
mittently shed into the Tithonian deposits (Pszczółkowski
1978, 1999)”.

Thus, the Pszczółkowski & Myczyński (2010) data sug-

gest that juvenile gastropods are linked to an important influ-
ence of shallow water derived clasts, but their interpretation
of  such  juvenile  gastropods  and  ammonites  identifies  them
as indicators of lower oxygen levels. In the studied section,
all gastropods found in the El Americano Member are resedi-
mented by tempestites and, they were not taken into consid-
eration because those entities do not reflect the physical and
chemical conditions that prevailed during the sedimentation
of the sample. The size of the gastropods and ammonites (ju-
venile)  is  not  due  to  lower  oxygen  levels,  it  is  the  result  of
the Stokes law. Small size gastropods and ammonites can be
transported longer distances. We are not in conflict with the
lower oxygenation of the sediment/seawater interface; abun-
dant  data  have  favoured  this  phenomenon.  However,  small
gastropods and ammonites are not part of those data.

“As a matter of fact, the paper by Fernández-López &
Meléndez (1995) concerns middle Jurassic ammonites, not
juvenile gastropods; the term “gastropods” does not appear
in this publication”.

This is a very peculiar observation and perhaps is based on a

misinterpretation of what is written in our paper. The work by
Fernández-López  &  Meléndez  (1995)  is  about  Taphonomic
Gradients  and  of  course,  we  agree  that  those  authors  used
Middle  Jurassic  ammonites  to  define  different  types  of  such
gradients. However, the definition of the gradients is based on
taphonomic,  and  not  necessarily  on  taxonomic  information.
Therefore, application of those gradients may be extended to
other  groups  besides  the  ammonites.  One  of  those  gradients
deals  with  the  process  of  remobilization,  while  the  other  is
based  on  the  size  of  the  specimens.  In  our  work  we  express
(on the basis of the size distribution of the assemblage regard-
less  of  the  taxonomic  group  involved),  that  the  taphonomic

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REPLY TO THE COMMENT ON “CALPIONELLID DISTRIBUTION... (SIERRA DE LOS ÓRGANOS)”

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 6, 499—501

gradients that explain the presence of juvenile and the scarcity
or lack of adult gastropods in Rancho San Vicente Section are
similar by analogy to those described for ammonites by
Fernández-López & Meléndez (1995).

“… Such  simple  extrapolation  does  not  work,  because
there  are  differences  between  various  sections  of  this  belt
as shown by the studies of previous authors. Moreover, the
authors  (López-Martínez  et  al.  2013)  did  not  take  into  ac-
count  some  important  arguments,  which  may  not  confirm
their  conclusions,  for  example,  distribution  of  ammonites
and  microfacies  documented  from  other  sections  in  previ-
ous publications”.

Pszczółkowski (2013, his comment) insists that there are

either  extrapolations  or  general  conclusions  to  embrace  the
whole Sierra de los Órganos in López-Martínez et al. (2013).
However,  our  results  count  exclusively  for  the  San  Vicente
section;  in  fact,  on  page 206,  in  reference  to  the  Simplex
Subzone  problem,  López-Martínez  et  al.  (2013)  state  “An
appropriate  explanation  of  this  phenomenon  is  out  of  the
scope  of  the  present  work,  and  perhaps  a  regional  detailed
composite section will be necessary to unravel this biostrati-
graphic interval in the future”.

Moreover, in our conclusions we emphasize that this con-

tribution is based on “high resolution sampling of an outcrop
of the Guasasa Formation in the Rancho San Vicente section
of the “Sierra de los Órganos””. In fact, there are no attempts
in  López-Martínez  et  al.  (2013)  to  make  conclusions  about
the whole Sierra de los Órganos area. It is clearly stated that
our  work  is  focused  on  only  one  section,  and  that  no  data
from other sections were used because it was not part of the
goal of the study. This assertion is even stressed on the very
first page of the manuscript, where the objective of the investi-
gation  is  clearly  stated:  “definition  of  an  updated  and  sound
calpionellid  biozonation  scheme  for  the  section”  (López-
Martínez et al. 2013, page 195, Abstract).

“Finally, the study of the San Vicente section improves but
does not change fundamentally the “good correlation of the
Jurassic/Cretaceous Cuban facies with European sections”
(López-Martínez et al. 2013, Conclusions), established by the
results of previous studies (Pop 1976, 1986; Pszczółkowski et
al. 2005; Pszczółkowski & Myczyński 2010).”

As stated before, the main goal of López-Martínez et al.

(2013) is “the definition of an updated and sound calpionel-
lid  biozonation  scheme  for  the  section”.  That  means  that
from  the  very  beginning,  while  planning  the  study,  we  in-
tended  to  improve  the  biostratigraphic  scheme  to  facilitate

more educated correlations with the coeval European sec-
tions. In that regard, we finally agree with this part of the
comment since the objective of López-Martínez et al. (2013)
has been fully accomplished.

References

Cobiella-Reguera J.L. & Olóriz F. 2009: Oxfordian—Berriasian

stratigraphy of the North American paleomargin in western
Cuba: Constraints for the geological history of the proto-Car-
ibbean and the early Gulf of Mexico. In: Bartolini C. & Román
Ramos J.R. (Eds.): Petroleum systems in the southern Gulf of
Mexico. AAPG Mem. 90, 421—451.

Fernández-López S. & Meléndez G. 1995: Taphonomic gradients in

Middle Jurassic ammonites of the Iberian Range (Spain). [Gra-
dients taphonomiques chez les ammonites du Jurassique Moyen
de la Chaîne Ibérique (Espagne)]. Geobios, M.S. 18, 155—165.

Houša V. & Nuez M.L. 1972: Hallazgo de ammonites del Kim-

meridgiano en Hacienda El Americano (Pinar del Rio). Actas,
Academia de Ciencias de Cuba, Inst. Geol. Paleont. 2, 14—16.

Iturralde-Vinent M.A. & Pszczółkowski A. 2011: Geología del ter-

reno Guaniguanico. In: Iturralde-Vinent M.A. (Ed.): Compen-
dio de Geología de Cuba y del Caribe. Primera Edición.
DVD-ROM. Editorial CITMATEL, La Habana, Cuba.

Jach R., Reháková D. & Uchman A. 2012: Biostratigraphy and pa-

leoenvironment of the Kimmeridgian—Lower Tithonian pelagic
deposits of the Krížna nappe, Lejowa Valley, Tatra Mts.
(southern Poland). Geol. Quart. 56, 4, 773—788.

López-Martínez R., Barragán R., Reháková D. & Cobiella-Reguera

J.L. 2013: Calpionellid distribution and microfacies across the
Jurassic/Cretaceous boundary in western Cuba (Sierra de los
Órganos). Geol. Carpathica 64, 3, 195—208.

Myczyński R. & Pszczółkowski A. 1990: Tithonian stratigraphy in

the Sierra de los Organos, Western Cuba: correlation of the am-
monite and microfossil zones. In: Fossili, Evoluzione, Ambiente
(Atti del secondo convegno internazionale, Pergola 25—30 ot-
tobre 1987). Edit. Comitato Cent. Raffaele Piccinini, 405—415.

Pop G. 1976: Tithonian—Valanginian calpionellid zones from Cuba.

D.S. ed., Inst. Geol. Geofiz. (3. Paleont.) 62, 237—266.

Pszczółkowski A. 1978: Geosynclinal sequences of the Cordillera de

Guaniguanico in western Cuba; their lithostratigraphy, facies de-
velopment, and paleogeography. Acta Geol. Pol. 28, 1, 1—96.

Pszczółkowski A. 1999: The exposed passive margin of North

America in western Cuba. In: Mann P. (Ed.): Caribbean basins.
Sedimentary basins of the World, 4 (series editor: Hsü K.J.).
Elsevier, Amsterdam, 93—121.

Pszczółkowski A. 2013: Comment on “Calpionellid distribution and

microfacies across the Jurassic/Cretaceous boundary in west-
ern Cuba (Sierra de los Órganos)” by López-Martínez et al.
(2013). Geol. Carpathica 64, 6, 497—498.

Pszczółkowski A. & Myczyński R. 2010: Tithonian—Early Valang-

inian evolution of deposition along the proto-Caribbean margin
of North America recorded in Guaniguanico successions
(western Cuba). J. South Amer. Earth Sci. 29, 225—253.