Carnets de Geologie is an academic journal focused on the field of geology, dedicated to publishing high-quality research papers and review articles covering various aspects of geology, including geological history, petrology, and mineralogy. The journal aims to provide a platform for researchers to communicate and share the latest research findings.

《Carnets de Geologie》是一本专注于地质学领域的学术期刊，致力于发表高质量的研究论文和综述文章，涵盖地质学的各个方面，包括地质历史、岩石学、矿物学等。期刊旨在为研究人员提供一个交流和分享最新研究成果的平台。

Carnets de Geologie

The Ankara region (central Türkiye) comprises a part of the Sakarya Terrane and the accretionary remnants inherited from the Izmir-Ankara-Erzincan (IAE) branch of the Northern Neotethys. The Sakarya Terrane is characterized by a pre-Jurassic basement overlain by Jurassic-Cretaceous sedimentary assemblages, collectively known as the Sakarya Continent Cover. In this study, we aim to elucidate the Jurassic-Cretaceous evolution of the Sakarya Terrane through detailed geological mapping in the regions of Haymana, Yakacık, north of Alagöz and west of Memlik, located to the west and southwest of Ankara city, central Türkiye. By analyzing radiolarian and planktonic foraminiferal assemblages, we provide precise dating for three key lithological units: the Soğukçam Limestone Group (part of the Sakarya Continent Cover), the Elmadağ Olistostrome, and the Unaz Formation (from the overlying units). The oldest rock unit exposed in the Haymana region, south of Ankara city, is the Bilecik Limestone Group, consisting of Tithonian to lower Berriasian platform carbonates. A drowning unconformity separates the Bilecik Limestone Group from the overlying middle Berriasian-uppermost Albian Soğukçam Limestone Group, which has been elevated to "group" status in this study. The Soğukçam Limestone Group is subdivided into two formations -the Seyran Formation and the Akkaya Formation- separated by a disconformity surface. The Seyran Formation, at the base, consists of middle Berriasian limestone breccia in a micritic pelagic matrix, and upper Berriasian-lower Aptian micritic clayey, cherty pelagic limestones with abundant and diverse radiolarians in its upper part. The disconformity between the Seyran and Akkaya formations represents a small depositional gap corresponding to the middle to late Aptian. The lower part of the Akkaya Formation contains lower to middle Albian debris flow deposits while the upper part is composed of clayey pelagic limestones rich in glauconite and planktonic foraminifers, dating to the latest Albian. Overall, the Akkaya Formation is roughly assigned to the Albian stage. The Akkaya Formation within the Soğukçam Limestone Group is unconformably overlain by the Coniacian Elmadağ Olistostrome, which also covers the ophiolitic mélange of the IAE Ocean (containing Turonian radiolarian blocks) to the west of the Memlik region. The basal part of the Elmadağ Olistostrome is characterized by an unstratified, loosely-packed, gray- to beige-colored carbonate matrix, while its upper part features stratified, highly-sheared gray- to beige-colored clayey carbonate/marl matrix with embedded carbonate blocks. These blocks, dated through radiolarians and planktonic foraminifers, range from the early Callovian to Coniacian. These blocks, observed in the Haymana, north of Alagöz, and Yakacık regions, primarily originated from the underlying Soğukçam Limestone Group. The Elmadağ Olistostrome was likely deposited in a peripheral foreland flysch basin, resembling trench-like settings, in front of the southward-moving nappes derived from the Neotethys Intra-Pontide Ocean. This olistostrome is unconformably overlain by the Unaz Formation, which represents the lowermost unit of the fore-arc basin within the Galatean Arc and is present in all four studied regions. The Unaz Formation mainly consists of thin-bedded, gray- to red-colored clayey limestones with abundant planktonic foraminifers, along with red- to pink-colored marls. In the northern part (west of Memlik), the Unaz Formation also includes basal clastics. Based on its characteristic planktonic foraminiferal assemblages, the formation is dated to the late Santonian and correlates well with the type locality in the Pontides, northwestern Türkiye. Following this sequence, a brief period of continental arc magmatism occurred in the Santonian-Campanian, accompanied by the deposition of fore-arc sediments (the Haymana Formation, consisting of clastics) during the Campanian-Maastrichtian interval. In this study, an abundant, well-preserved, and diverse radiolarian microfauna (146 taxa, including fourteen new species and four new subspecies from the early Hauterivian to early Aptian, Early Cretaceous) were recovered from the clayey micritic limestones of the Seyran Formation in the Soğukçam Limestone Group. The vertical distributions of these radiolarians and their age correlations with previous studies are also documented.

U. Kağan Tekin

Bilal Sarı

Alaettin Tuncer

Kaan Sayit

Cengiz Okuyucu

Çağrı Güzgün

Carnets de géologie (Notebooks on geology)

Radiolarian and planktonic foraminiferal biochronology of the Soğukçam Limestone Group, Elmadağ Olistostrome, and Unaz Formation (Ankara region, central Türkiye): Insights into the Cretaceous evolution of the Sakarya Continent and overlying units

Soğukçam石灰岩群、Elmadağ滑塌岩和Unaz组（土耳其安卡拉地区中部）的放射虫和浮游有孔虫生物年代学：揭示萨卡里亚大陆及其上覆地层的白垩纪演化

The Coskinolinidae are a family of Middle Jurassic to Paleogene, typically orbitoliniform, Larger Benthic Foraminifera (LBF) characterized by a pseudokeriothecal wall structure. The type genus, Coskinolina Stache, 1875, lacks an exoskeleton (i.e., beams, rafters), resulting in an undivided marginal chamber zone. However, other taxa within the family, such as the Upper Cretaceous Lepinoconus Cruz-Abad et al., 2017, or the Paleogene Coleiconus Hottinger &amp; Drobne, 1980, are genera with vertical partitions (beams) that subdivide the marginal chamber zone. In the currently accepted classification of agglutinated benthic foraminifera, the nature of the exoskeleton is a criterion for distinction at subfamily level, e.g., Cyclamminidae Marie, 1941. Thus, here, the presence or absence of an exoskeleton in the marginal chamber lumen is treated as a criterion at the subfamily level within the classification of the Coskinolinidae, leading to a division into two subfamilies: the Coskinolininae Moullade, 1965 (lacking an exoskeleton), and the newly proposed Coleiconinae subfam. nov. (with an exoskeleton of vertical partitions), as exemplified by Coleiconus Hottinger &amp; Drobne, 1980.

Felix Schlagintweit

A new subfamily classification of the Coskinolinidae Moullade, 1965, Middle Jurassic-Paleogene Larger Benthic Foraminifera

中新世-古近纪大型底栖有孔虫Coskinolinidae Moullade, 1965新亚科分类

A new paracomatulid crinoid, Tiburtocrinus toarcensis gen. et sp. nov., is described from the Lower Jurassic of Tivoli (central Apennines, Italy). This type of stemless crinoids has never previously been recorded in Italy, and this report bridges a significant gap. Morphofunctional analysis of the radial facets suggests that Tiburtocrinus toarcensis gen. et sp. nov. may have been a crawling paracomatulid, very different from other paracomatulids that probably swam.

Riccardo Manni

Rolando Di Nardo

A possible crawling paracomatulid crinoid from the Lower Jurassic of central Italy

意大利中部下侏罗纪可能的爬行类副花鳞海百合

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.

Artur Chahud

Comments on a small sabretooth cat in the Abismo Ponta de Flecha Cave, Vale do Ribeira, southeastern Brazil

关于巴西东南部里贝拉谷阿比索波纳弗莱亚洞穴中一种小型剑齿猫的评论

The 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 segment.

Gérard Delanoy

Cyril Baudouin

Antoine Pictet

Josep Moreno-Bedmar

Camille Frau

Bertrand Matrion

The genera Roloboceras Casey, 1954, and Megatyloceras Humphrey, 1949 (Ammonoidea, Ancyloceratina, Douvilleiceratidae), from the Lower Aptian of Ardèche (SE France) - Taxonomic and biostratigraphic implications

罗洛贝壳属（Casey，1954）和大圆顶贝壳属（Humphrey，1949）（菊石目，钩菊石亚目，杜维尔菊石科）来自法国东南部阿尔代什下阿普第阶的分类学和生物地层学意义

In the literature, numerous accounts exist of microspheres scattered in the pelagic environments of the Tethys realm at the Jurassic-Cretaceous transition. These microspheres are commonly associated with genera such as Cadosina, Colomisphaera, or Stomiosphaera, and attributed to calcareous dinocysts. On the other hand, there are few records of the microsphere, initially described as Cadosina minuta BORZA, 1980, which are arranged in small clusters, likely comprising six cells. This distinctive grouping and its architecture preclude attribution to the calcareous dinocysts. A new genus and a new species (as Octahedronoides tethysianus n.gen., n.sp.) are introduced to define these clusters of leiospheres, which are here reascribed to the acritarchs.

Bruno R.C. Granier

Octahedronoides tethysianus n.gen., n.sp., enigmatic clusters of microspheres at the Jurassic-Cretaceous transition

新属新种泰提斯八面体球群（Octahedronoides tethysianus n.gen., n.sp.）：侏罗纪-白垩纪过渡期的神秘微球团簇

A new species, †Nannotanyderus granieri sp. nov., belonging to the Tanyderidae (Diptera, Nematocera), from Lower Barremian amber of Bqaatouta (Lebanon), is characterized, described, figured, and its taxononomic position discussed. The possible confusion regarding the attribution of new fossils to either the Tanyderidae or the Psychodidae, in addition to the results of recent molecular phylogenies, have led us to re-evaluate the taxonomic position of the Tanyderidae and to consider it as a subfamily within the Psychodidae. The fossil described herein is a tiny tanyderine sensu nov. species, and the second one belonging to the genus Nannotanyderus from Lebanese amber. A tentative molecular phylogeny of recent Psychodidae and an exhaustive catalogue of fossil Tanyderinae stat. nov. are provided.

Dany Azar

Sibelle Maksoud

Di-Ying Huang

Mounir Maalouf

Chen-Yang Cai

A new fossil psychodomorphan fly from Lower Barremian Lebanese amber elucidates the relationship of the Tanyderinae stat. nov. within the Psychodidae

黎巴嫩下巴列姆阶琥珀中新发现的一种长翅目昆虫揭示了新建立的Tanyderinae亚科在长翅目中的关系

Broken ooids are known to occur in both aragonitic and calcitic ooids with radial fabrics. In the literature, it has been suggested that synsedimentary breakage could be related to attrition/mechanical impacts, hypersalinity, or desiccation. However, this paper demonstrates that none of the aforementioned phenomena provides a valid explanation. Although the exact process remains unknown (potentially involving some synsedimentary recrystallization), it is shown that: 1) the breakage is genetically linked to the radial fabrics; 2) the ratio of ooid breakages increases with the relative thickness of the radial cortical layers; 3) fracture growth in broken ooids proceeds centripetally.

Philippe Lapointe

The Kalkowsky Project - Chapter VI. A panorama of synsedimentary broken ooids

卡尔科夫斯基项目 - 第六章。同生碎屑鲕粒全景

Abbreviation
Journal Impact	1.35
Quartiles(Global)	PALEONTOLOGY(Q2)

ISSN	1634-0744, 1765-2553, 2108-5196
h-index	20

Publication Information	Publisher: Carnets de Geologie，Publishing cycle: Irregular，Journal Type: journal，Open Access Journals: Yes
Basic data	Year of publication: 2007，Proportion of original research papers: 100.00%，Self Citation Rate:6.70%， Gold OA Rate: 0.00%
Average review cycle	网友分享经验：>12周，或约稿
Average recruitment ratio	网友分享经验：容易

Carnets de Geologie

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Radiolarian and planktonic foraminiferal biochronology of the Soğukçam Limestone Group, Elmadağ Olistostrome, and Unaz Formation (Ankara region, central Türkiye): Insights into the Cretaceous evolution of the Sakarya Continent and overlying units

A new subfamily classification of the Coskinolinidae Moullade, 1965, Middle Jurassic-Paleogene Larger Benthic Foraminifera

A possible crawling paracomatulid crinoid from the Lower Jurassic of central Italy

Comments on a small sabretooth cat in the Abismo Ponta de Flecha Cave, Vale do Ribeira, southeastern Brazil

The genera Roloboceras Casey, 1954, and Megatyloceras Humphrey, 1949 (Ammonoidea, Ancyloceratina, Douvilleiceratidae), from the Lower Aptian of Ardèche (SE France) - Taxonomic and biostratigraphic implications

Radiolarian and planktonic foraminiferal biochronology of the Soğukçam Limestone Group, Elmadağ Olistostrome, and Unaz Formation (Ankara region, central Türkiye): Insights into the Cretaceous evolution of the Sakarya Continent and overlying units

A new subfamily classification of the Coskinolinidae Moullade, 1965, Middle Jurassic-Paleogene Larger Benthic Foraminifera

Octahedronoides tethysianus n.gen., n.sp., enigmatic clusters of microspheres at the Jurassic-Cretaceous transition

A new fossil psychodomorphan fly from Lower Barremian Lebanese amber elucidates the relationship of the Tanyderinae stat. nov. within the Psychodidae

The Kalkowsky Project - Chapter VI. A panorama of synsedimentary broken ooids