2022 (vol. 22)
A larger benthic foraminiferal zonation for the Eocene of the Caribbean and central American region
Simon F. MITCHELL, Edward ROBINSON, Ercan ÖZCAN, Mark M. JIANG & Natalie ROBINSON
| PDF [43,031 KB]
| DOI : 10.2110/carnets.2022.2211
Abstract: We have undertaken a study of the larger benthic foraminifera
(LBF) of the Eocene of Jamaica that involved collecting free specimens and calibrating their occurrence against chronostratigraphy using calcareous nannofossils identified from sample splits or adjacent samples. The
results have been plotted stratigraphically and allow a detailed zonation of the Eocene (14 zones) to be developed based largely on lepidocyclinids and similar forms. The zonation can be shown to be applicable to the Americas extending from northern South America, to Central America, the Caribbean and southern North America. The LBF biostratigraphy is based on the evolution of various groups. Three zones are recognized in the
Ypresian, six zones in the Lutetian, three zones in the Bartonian, and two zones in the
Priabonian. In order to classify the LBF we have revised the important groups used for the zonation scheme that occur in the Eocene and figure numerous examples. Our revision rearranges described genera into evolutionary, monophyletic clades to which we give the hierarchy of family and subfamily. We provide remarks on published taxa explaining how they are recognized and describe all the new taxa (two families, one subfamily, four genera and five species). The following families, genera and species are new: Butterliniana gen.
nov., Helicosteginidae fam. nov., Helicostegina minor sp. nov., Helicostegina jamaicensis sp.
nov., Helicostegina jeannemairae sp. nov., Pseudolepidinidae fam. nov., Orbitoininae
subfam. nov., Planorbitoinella gen. nov., Polyorbitoinella gen.
nov., Polyorbitoinella lilyfieldensis sp. nov., Orbitoina wrighti sp.
nov., and Nephronummulites gen. nov.
Carnets Geol., vol. 22, no. 11, p. 409-565
Online since July 1, 2022
Discussion of Laya et al. (2021), Dissolution of ooids in seawater-derived fluids - an example from Lower Permian re-sedimented carbonates, West Texas, USA [Sedimentology 68(6), 2671-2706]
Bruno R.C. GRANIER & Christopher G.St.C. KENDALL
| PDF [5,046 KB]
| DOI : 10.2110/carnets.2022.2210
discussion reassesses earlier interpretations of calcareous turbidites from the
subsurface Spraberry Formation of the Happy Field (Garza County, NW Texas). It is based on routine petrographic analyses
with a standard microscope. The succession of diagenetic products in this deep
water setting were a little initial cementation by low magnesian calcite (LMC)
and then the partial or complete leaching of both aragonite and high magnesian
calcite (HMC) allochems facilitated by the presence of a residual primary
intergranular porosity. This contradicts Laya et al.'s (2021)
claim that cementation left no residual intergranular porosity so further
leaching of the ooids would not have been possible. Instead the study made for
this discussion with the same thin sections found residual primary intergranular
porosity remains as evidenced by some of their photomicrographs. Most thin
sections with porous grainstones have 1) collapsed molds that exhibit evidence
of little initial cementation and 2) measured permeability values that range from some
mD to some tens of mD. Isopachous LMC cements occur in almost all thin sections
lining the margins of most intergranular pores. As these cements do not fully
fill the pores, there is permeable well-connected residual primary porosity with
no significant LMC cement in the secondary moldic porosity. Compaction affects
the allochems and, where these are partially leached, intergranular and moldic
porosities. Dissolution of aragonite (a major component) and HMC (possibly a
minor component) was probably not coeval. The order of paragenetic sequence of
this discussion study was: 1) LMC cementation; 2) aragonite leaching facilitated
by oxidation of the organic matter in the "biocrystals" of bioclasts
and oolitic cortices; 3) compactional brecciation, which was first mechanical,
and then chemical causing local collapse of the molds of some of the largest
pores. It was governed by cementation
initially in a shallow burial diagenetic setting and then leaching whereas
chemical compaction marks a slightly deeper burial diagenetic setting. The final
event was marked by oil migration into the Happy Field reservoirs, freezing the
calcium carbonate diagenesis. The theory of Laya et al. (2021) of
the leaching of ooids in directly "seawater-derived fluids" is unsupported by
the paragenetic sequence described above.
the reading of a paper authored by J.C. Laya et al. in the journal
Sedimentology, the authors submitted on 02-Nov-2021 a first discussion
manuscript based on analogues. On 09-Nov-2021, this first manuscript was
returned with harsh comments from three editors and ascribed the label "Reject
& Resubmit". On 07-Mar-2022, the first author (BRCG)
received a parcel with 40 thin sections to examine over a two weeks period. He
was charged significant import taxes for this "scientific material".
On 14-May-2022, the authors submitted a new discussion manuscript based on that
same material that was studied by J.C. Laya et al. On 07-Jun-2022
this second manuscript was ascribed the label "Immediate Reject"
without having any preliminary editorial reading. In the meantime, a claimant
allegedly accused the first author (BRCG) of "serious breaches in academic
publishing ethics" because he posted some photomicrographs of the material
on a social network. On 05-Apr-2022 and again on 18-May-2022, this claimant addressed
complains to the " Université
de Bretagne Occidentale", an action that may be characterised as slander or
defamation. Note that the authors were kindly granted the written permission to
publish this discussion paper and another paper by the legitimate owner of the
Happy Spraberry field, which also owns all material derived from any of their
materials (e.g., cores). It looks like there is no evidence that it was the case for the other parties.
Carnets Geol., vol. 22, no. 10, p. 395-408
Online since June 19, 2022
A rare ammonite assemblage in the Romaniceras ornatissimum Zone (Middle Turonian) from the Uchaux Massif, Vaucluse, France
Francis AMÉDRO, Cyril BAUDOUIN, Gérard DELANOY, Christian DELVAQUE & Francis ROBASZYNSKI
| PDF [7,869 KB]
| DOI : 10.2110/carnets.2022.2209
Abstract: The Uchaux Massif (Vaucluse, SE France) is one of the rare places in Europe where ammonites collecting can be led from a high middle Turonian through Late Turonian. That incited Alcide d'Orbigny in 1852 to quote Uchaux as "the French type of the Turonian stage" to complement the Saumur, Tourtenay, Montrichard and Tours localities mentionned in 1842 when the stage was created. In 2014, the monograph by Robaszynski et al. synthetized and actualized the informations available on the litho- and biostratigraphy of the Turonian from the Uchaux Massif. More recently, a new outcrop at Mondragon, in a place named Prés Morel, exposes the whole carbonate siltstones with Spongia of the Peyras Member (UL3). Were collected : Lewesiceras peramplum (Mantell, 1822), Romaniceras (Romaniceras) marigniacum Amédro & Châtelier, 2020, R. (Yubariceras) ornatissimum (Stoliczka, 1864), R. (Y.) kanei Jones, 1938, Collignoniceras woollgari regulare (Haas, 1946), C. carolinum (Orbigny, 1841), C. papale (Orbigny, 1841), C. turoniense (Orbigny, 1841) and a new species of Collignoniceras : C. rhodanicum Amédro, Baudouin & Delanoy sp. nov. This assemblage, unprecedented in the studied area, is characteristic of the Romaniceras ornatissimum
Zone which is the third of the four ammonite zones of the middle Turonian (Tm 3). At the top of this third zone, the surprise was to find the Romaniceras marigniacum bio-horizon defined in 2020 in the southern part of the Paris Basin at the top of the Tuffeau de Bourré and at the base of the Tuffeau Jaune de Touraine. Moreover, we now think that the Peyras Member has to be fully assigned to the Romaniceras ornatissimum
Zone. Lastly, the assemblage includes a rich population of Collignoniceras carolinum (24 specimens), the most important known to-day over the world. All these ammonites allow to know the spectrum of their morphological variations and show a dimorphism through the existence of micro- and macroconchs.
Carnets Geol., vol. 22, no. 9, p. 333-393
Online since June 18, 2022
The Kalkowsky Project - Chapter IV. Case study of the Happy Spraberry oil reservoirs in NW Texas (with a micropaleontologic and biostratigraphic supplement): Collapsed molds should not be treated as a category of distorted ooids
Bruno R.C. GRANIER, Christopher G.St.C. KENDALL & Daniel VACHARD
| PDF [6,180 KB]
| DOI : 10.2110/carnets.2022.2208
subsurface upper Spraberry Formation in NW Texas is dominantly composed of
calcareous turbidites and debris-flows. The petrographic analysis of its porous grain-supported fabrics revealed the presence of
controversial superimposed compaction fabrics, sometimes referred to as "distorted
ooids". Based on the paragenetic sequence, it is demonstrated that these
allochems were not distorted. In fact, the related zigzag and silcrow (§) patterns
result from the collapse of molds, either oomolds or biomolds, in response to
mechanical compaction of the fragile framework made up of isopachous Low-Mg
Calcite cement surrounding these empty molds. As a side finding, this
stratigraphic unit, which was said to be late Kungurian in age, is proved to
be nearly 7 millions of year older.
Carnets Geol., vol. 22, no. 8, p. 311-332
Online since June 2, 2022
Taxonomy of the fossil calcareous algae: Revision of genera Physoporella Steinmann and Oligoporella Pia (Dasycladales)
| PDF [31,142 KB]
| DOI : 10.2110/carnets.2022.2207
Abstract: The taxonomic classification and mutual distinction of the genera Physoporella Steinmann and Oligoporella Pia (Dasycladales, green algae) have proven problematic and that has impeded their use in stratigraphy and other studies. The presence of single whorls of piriform laterals in Physoporella and double whorls in Oligoporella is considered as the main characteristic that separates these genera. According to that, diagnoses of genera and all species and varieties are changed or supplemented, and detailed descriptions are given. For this purpose the type-material from Pia's collection was re-examined and its redocumentation and reinterpretation performed. Additional information was obtained from abundant material from Croatia (Ivančica Mt, Medvednica Mt, umberak Mt, Lika, Dalmatia). Only a few taxa were examined based on literature data. For all species and varieties reconstructions are given. Taxa from the Permian of East Asia are only briefly described. Among the investigated taxa, some of them have a structure that significantly differs from that present in the type species of the genera Physoporella and Oligoporella. They are separated into two new genera Ardeiporella and Neophysoporella. The revised genera Physoporella and Oligoporella, together with the newly established ones, give a clearer picture of phylogenetic relations.
Carnets Geol., vol. 22, no. 7, p. 171-310
Online since June 4, 2022
The report of a rare deformed eagle ray (Myliobatiformes: Myliobatidae) tooth plate from the Neogene of Calvert Cliffs, Maryland, U.S.A.
Stephen J. GODFREY, David J. BOHASKA & John MAISEY
| PDF [937 KB]
| DOI : 10.2110/carnets.2022.2206
Abstract: An isolated and deformed
lower tooth plate of an eagle ray (Aetomylaeus
sp., Myliobatidae, Myliobatiformes) is reported herein from the Miocene deposits
along Calvert Cliffs, Maryland, U.S.A. Deformed myliobatid tooth plates like
this, either fossil or modern, are exceedingly rare. All medial teeth are
deformed/skewed such that the right side of each tooth forms an angle of about
10 degrees to the transverse axis of the dental plate. The skewed abnormal form
of the teeth in USNM PAL 726325
is not thought to be the result of modern or taphonomic deformation. Rather, the
deformity exhibited by USNM PAL 726325
gives every indication that successive similarly deformed teeth came about as a
result of a persistent anatomical deformity of the dental lamina. From the
consistency in the deformed shape of each tooth, it would appear as though the
dental lamina retained this anomalous shape at least throughout the time
represented by the age of the tooth plate. If this interpretation is correct,
the deformity was not fatal and did not significantly impair the functionality
of the tooth pavement over a protracted part (or all) of the individual's life
Carnets Geol., vol. 22, no. 6, p. 161-169
Online since May 10, 2022
The Kalkowsky Project - Chapter III. Significance of primary radial fabrics associated with ancient partly leached or recrystallized calcareous ooids
Bruno R.C. GRANIER & Philippe LAPOINTE
| PDF [1,851 KB]
| DOI : 10.2110/carnets.2022.2205
Abstract: Calcitic ooids and bothryoids from
the Yacoraite Formation in the provinces of Jujuy and Salta (Argentina) display
radial fabrics pointing to their primarily high-Mg calcite (HMC) nature. The
present publication documents some specimens that are partly or fully leached
or recrystallized, which raises fundamental questions about the validity of
some concepts, such as the very existence of the so-called "two-phase"/"bimineralic"
ooids. It is assumed here that the organic content in the oolitic cortices
(and, subsequently, its degree of oxidation) is the key to explaining some
differential diagenetic alterations.
Carnets Geol., vol. 22, no. 5, p. 149-160
Online since March 4, 2022
Adult morphologies of Puzosia quenstedti (Parona & Bonarelli, 1897) (Ammonoidea, Desmoceratidae) in the Albian of the South-East of France. Taxonomic implications
Jean-Louis Latil LATIL, Gérard DELANOY & Pierre DELATTRE
| PDF [5,643 KB]
| DOI : 10.2110/carnets.2022.2204
Abstract: Several adult specimens belonging to the genus Puzosia
Bayle, 1878, were collected in the Albian of Lieuche
(Alpes-Maritimes, France). Comparison with material from the condensed Albian levels of La Balme
de Rencurel (Isère, France), in particular those described and figured by Jacob
(1908), has highlighted a morphological link between the adult forms from
Lieuche and the incomplete specimens from the condensed levels of the Lower-Middle Albian of
south-eastern France and to identify them as Puzosia quenstedti (Parona
& Bonarelli, 1897).
These new details on the ontogenetic development of this species also allow new perspectives in
the taxonomic treatment of Albian Puzosia species. A modified diagnosis of Puzosia
quenstedti is proposed.
The presence of Douvilleiceras sp. juv. aff. D. mammillatum (Schlotheim,
1813) in superimposed overlying levels allows assignation of a Lower Albian (Douvilleiceras
mammillatum Superzone) to a basal Middle Albian age (Hoplites dentatus Zone).
Carnets Geol., vol. 22, no. 4, p. 119-147
Online since February 28, 2022
The Kalkowsky Project - Chapter II. Wobbly ooids in a stromatolite from the Yacoraite Formation (Argentina)
Bruno R.C. GRANIER & Philippe LAPOINTE
| PDF [1,375 KB]
| DOI : 10.2110/carnets.2022.2203
Abstract: Eccentric ooids are described from a brackish
Maastrichtian paleolake in NW Argentina. The first report of such atypical
coated grains was from marine Upper Jurassic strata in SE Poland. Because their
growth pattern is not likely to be confused with that of other
"eccentric" ooids, such as asymmetric ooids, hiatus ooids, half-moon
ooids, or "broken" ooids, it is suggested here to name them
Carnets Geol., vol. 22, no. 3, p. 111-117
Online since February 15, 2022
The genera Roloboceras Casey, 1954, and Megatyloceras Humphrey, 1949 (Ammonoidea, Ancyloceratina, Douvilleiceratidae), from the Lower Aptian of Ardèche (SE France) - Taxonomic and biostratigraphic implications
Gérard DELANOY, Cyril BAUDOUIN, Antoine PICTET, Josep MORENO-BEDMAR, Camille FRAU & Bertrand MATRION
| PDF [11,947 KB]
| DOI : 10.2110/carnets.2022.2202
Lower Aptian marine deposits from southern Ardèche (South-East of France) yield
a rich ammonite fauna of the sub-family Roloboceratinae Casey,
1961, which dates the upper Deshayesites
forbesi Zone (Roloboceras hambrovi
Subzone pro parte ?). The systematic study of this Roloboceratinae fauna
has improved our knowledge of Megatyloceras
coronatum Rouchadzé, 1933, type species of Megatyloceras Humphrey,
1949, as well as a better understanding of the genus thanks to the examination
of the species from the Anglo-Paris Basin. A new species, M.
leteilensis sp. nov. is introduced, and a description of M.
transiens Casey, 1961, provided, with clarifications on its possible
stratigraphic position. This study also establishes that the "species" Megatyloceras
ricordeanum (Orbigny, 1850) represents only a growth stage shared by
several species of Megatyloceras which is doubtfully a true taxon
and must, therefore, be considered as a nomen dubium.
The hypothesis of sexual dimorphism in Roloboceras
Casey, 1954, and Megatyloceras
is advanced. The study of this Roloboceratinae fauna highlights their
heterogeneous distribution throughout Lower Aptian deposits of Ardèche, showing
a direct correlation with bathymetric range. The biostratigraphical distribution
of both genera on the Languedoc platform shows that Roloboceras is
present from the uppermost C2 segment to the C4 segment of the stable
carbon-isotope record, while Megatyloceras is limited to the middle C4
segment up to the lowermost C6 segment. Both genera coexist during the C4
Carnets Geol., vol. 22, no. 2, p. 7-109
Online since February 17, 2022
Nomenclatural Note, p.
Comments on a small sabretooth cat in the Abismo Ponta de Flecha Cave, Vale do Ribeira, southeastern Brazil
| PDF [448 KB]
| DOI : 10.2110/carnets.2022.2201
Abstract: Vale do Ribeira, in southeastern Brazil, is known for its many
caves that contain osteological material, including remains that have been
referred to several extinct species. The sabertooth cat Smilodon populator was a large predator that inhabited South America
during the Quaternary. A specimen that is represented in the Abismo Ponta de
Flecha Cave by small forelimb bones (metacarpals and phalanges) is commented
here. The metacarpals display morphological characteristics of S.
populator, but are smaller than those of S.
fatalis and larger than those of S.
gracilis. This specimen is amongst the smallest ever found specimen of S.
populator and is comparable in size to an adult lion.
Carnets Geol., vol. 22, no. 1, p. 1-6
Online since January 17, 2022