Cretaceous Research最新文献_第4页

Diversity of araucariacean pollen from the Lower Cretaceous Rio da Batateira and lower Crato formations (Araripe basin, SE Brazil), based on micromorphology of the ektexine using SEM 巴西东南部Araripe盆地下白垩统里约热内卢da Batateira和下Crato组araucariacaceae花粉的SEM显微形态分析

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-28 DOI: 10.1016/j.cretres.2025.106260

Christa-Ch Hofmann , Mario Coiro , Ulrich Heimhofer , Emily A. Roberts , Leyla J. Seyfullah

Here we demonstrate the micromorphological variety of Aptian pollen grains affiliated with Araucariaceae s.l. with LM and SEM. We could distinguish five micromorphological groups and in addition to well known araucariacean pollen taxa such as Araucariacites spp., Balmeiopsis and Callialasporites spp., we could also assign Exesipollenites scabratus, E. cf. tumulus, and one Inaperturopollenites taxon as araucariacean. Using LM, a hidden diversity of micromorphological features are missed within the four pollen taxa (“Araucariaceae” sp. 1 to sp. 4) that are similar to the morphogenus Araucariacites demonstrating the importance of using scanning electron microscopy in palaeopalynology. Pollen characterized by micromorphological features of group 4 comprises Callialasporites spp., Inaperturopollenites sp. and “Araucariaceae” sp. 1 and are assumed to be dispersed equivalents of previously described eurypalynous pollen cones. These pollen cones and pollen grains might represent an ancient group of Araucariaceae with overlapping characters from Podocarpaceae and Araucariaceae. In total 15 Araucariaceae pollen taxa are present in the Rio da Batateira and lower Crato formations, a number that exceeds the diversity of previously described araucariacean macrofossils and pollen of the Araripe basin. These results are evidence that despite the rapid evolution of angiosperms in the Early Cretaceous, gymnosperms, particularly Araucariaceae, still played an important role in various ancient vegetation habitats.

本文利用光谱学和扫描电镜研究了阿普天科阿普天科花粉粒的显微形态变化。除了Araucariacites spp.、Balmeiopsis和Callialasporites spp.等已知的Araucariacites花粉类群外，还可以将Exesipollenites scabratus、E. cf. tumulus和一个Inaperturopollenites分类群划归为Araucariacites。利用扫描电镜技术，在与Araucariacites形态属相似的4个花粉分类群（“Araucariaceae”sp. 1至sp. 4）中遗漏了隐藏的微形态特征多样性，这表明了扫描电镜技术在古孢粉学中的重要性。以微形态特征为特征的第4组花粉包括Callialasporites spp., Inaperturopollenites sp.和Araucariaceae sp. 1，它们被认为是先前描述的泛孢花粉球果的分散等量物。这些花粉球果和花粉粒可能代表了一个古老的类群，它们具有木足科和木足科的重叠特征。在里约热内卢da Batateira和下克拉托地层中，共有15个araucariacaceae花粉分类群，其数量超过了先前描述的Araripe盆地araucariacaceae大化石和花粉的多样性。这些结果表明，尽管被子植物在早白垩世迅速进化，裸子植物，特别是砂桃科，仍然在各种古代植被栖息地中发挥着重要作用。

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引用次数: 0

A new large zalambdalestid mammal from the Gobi Desert and formal stratigraphic description of the Upper Cretaceous Zos Formation 戈壁沙漠一种新的大型zalamdalestid哺乳动物和上白垩统Zos组的正式地层描述

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-25 DOI: 10.1016/j.cretres.2025.106253

Michael J. Novacek , William M. Wolfe , Maureen A. O'Leary , Eric M. Roberts

We describe Zoslestes gongori, a new species of non-placental eutherian mammal from Upper Cretaceous rocks of Zos Canyon in the Nemegt Basin of the western Gobi Desert, Mongolia. Zoslestes gongori is the largest known zalambdalestid. The Zos Canyon locality, Red Rum, that yielded the specimen is adjacent to beds that have produced several extinct crocodyliforms and the ornithischian dinosaur Haya griva. We provide the first formal stratigraphic description of these fossiliferous Zos Canyon rocks by naming and describing the Zos Formation for the unit at Red Rum. The Zos Formation has a distinct set of sedimentologic associations that differentiate it from the overlying Djadokhta Formation and also has the only fauna in the Nemegt Basin older than that of the Djadokhta Formation. We consider the Zos Formation roughly comparable in age to the Javkhlant Formation of the Eastern Gobi Desert, and likely older than the Alagteeg Formation of the Ulan Nur Basin.

Zoslestes gongori is known from the holotype, a well-preserved posterior cranium, worn dentition, and fragmentary postcranial elements, and one referred specimen. The referred specimen consists of a damaged anterior skull and dentition, and a fragmentary left mandible with roots and alveoli, including an enlarged tooth resembling the elongate first lower incisor of zalambdalestids. Zoslestes shares several derived features with zalambdalestids, including the presence of a prominent entoglenoid process that, in ventral view, partly conceals the anteriorly-positioned postglenoid foramen, a large maxillary tuberosity, multiple hypoglossal foramina, a large, elongate i1 with a horizontally directed root extending deep within the mandible, lower molars with mesiodistally compressed trigonids and relatively wide talonids, a relatively large P4, and upper molars that are distinctly wider labiolingually than long mesiodistally and that are not interlocked mesiodistally. The significantly large size of Zoslestes and the large contribution of its jugal to the zygomatic process are autapomorphies distinguishing this taxon from other zalambdalestids.

本文描述了在蒙古戈壁西部Nemegt盆地Zos峡谷上白垩世岩石中发现的一种非胎盘哺乳类动物Zoslestes gonori。扁角虫是已知最大的扁角虫。在佐斯峡谷的红朗姆地区，发现了这个标本，附近的地层曾发现过几种已灭绝的鳄鱼目恐龙和鸟臀目恐龙。我们通过命名和描述在Red Rum的单位的Zos组，提供了这些化石的Zos峡谷岩石的第一个正式的地层描述。Zos组与上覆的Djadokhta组有着独特的沉积学联系，也是Nemegt盆地中唯一比Djadokhta组更古老的动物群。我们认为Zos组的年龄与东部戈壁沙漠的Javkhlant组大致相当，可能比乌兰淖尔盆地的Alagteeg组更古老。我们从完整的模型、保存完好的后颅骨、磨损的牙列、残缺的颅后器官和一个参考标本中了解到小狐猴。所提到的标本包括一个受损的前颅骨和牙列，一个带有根和牙槽的碎片左下颌骨，包括一颗类似于zalambdalestid的细长的第一下门牙的扩大的牙齿。Zoslestes与zalambdalestids有几个共同的衍生特征，包括有一个突出的盂内突，从腹侧看，它部分隐藏了位于前方的盂后孔，一个大的上颌结节，多个舌下孔，一个大的，细长的i1，一个水平方向的根延伸到下颌骨深处，下磨牙中远端压缩三角肌和相对宽的距骨，一个相对大的P4，上磨牙在唇上明显宽而在中离侧明显长并且在中离侧没有互锁。Zoslestes的巨大体型和对颧突的巨大贡献是该分类群区别于其他zalambdalestes的自形特征。

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引用次数: 0

Stratigraphic sequence and age determination of the cretaceous rift-sag transition period in the Songliao basin, NE China: Based on new data from ICDP boreholes SK2 and SK3 松辽盆地白垩系断陷过渡期的层序及年龄测定——基于ICDP SK2和SK3井的新资料

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-22 DOI: 10.1016/j.cretres.2025.106257

Shuo Liu , Youfeng Gao , Renjie Liang , Pujun Wang , Haibo Liu

The Songliao Basin's tectonic evolution comprises three stages: the syn-rift stage, post-rift stage, and structural inversion stage. The Yingcheng Formation and the Denglouku Formation record the strata corresponding to the transitional period from the syn-rift stage to the post-rift stage. However, the stratigraphic boundary between these two formations and the sedimentation time of the Denglouku Formation remain controversial. This paper undertakes a zircon isotope chronology study on the tuff from the lower part of the Denglouku Formation, based on the continuous coring data from the International Continental Scientific Drilling Program (ICDP) boreholes SK2 and SK3 in the Songliao Basin. The LA-ICP-MS U–Pb age of the tuff at 2359.35 m depth in the lower part of the Denglouku Formation in borehole SK3 is determined to be 105.4 ± 0.6 Ma, constraining the initial sedimentation time of the Denglouku Formation, while an age of 103.4 ± 0.8 Ma from the tuff at 2970.65 m at the base of the Denglouku Formation in borehole SK2 marks the end of the first member's sedimentation. By integrating the existing chronostratigraphic data with basin-scale stratigraphic correlations from the Songliao Basin, this study re-evaluates the controversial sandy conglomerates within the fourth member of the Yingcheng Formation in the northern Songliao Basin, demonstrating their affinity to the first member of the Denglouku Formation.

松辽盆地的构造演化分为三个阶段：同裂谷期、裂谷后期和构造反转期。营城组和登娄库组记录了同裂谷期向后裂谷期过渡时期的地层。但是，这两组的地层界线和登楼库组的沉积时间仍有争议。利用国际大陆科学钻探计划（ICDP） SK2、SK3井连续取心资料，对松辽盆地登娄库组下部凝灰岩进行了锆石同位素年代学研究。SK3钻孔登娄库组下部2359.35 m处凝灰岩LA-ICP-MS U-Pb年龄为105.4±0.6 Ma，限定了登娄库组的初始沉积时间；SK2钻孔登娄库组底部2970.65 m处凝灰岩年龄为103.4±0.8 Ma，标志着登娄库组一段沉积结束。结合松辽盆地已有的年代地层资料和盆地尺度地层对比，对松辽盆地北部营城组四段有争议的砂质砾岩进行了重新评价，表明其与登娄库组一段具有亲缘关系。

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引用次数: 0

Seawater properties based on clumped isotope analyses of macrofossil assemblages from the Upper Cretaceous–lower Paleocene Type-Maastrichtian area 基于马斯特里赫特地区上白垩统-下古新统大化石组合块状同位素分析的海水性质

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-22 DOI: 10.1016/j.cretres.2025.106258

Inigo A. Müller , David Rijkes , Emily J. Judd , Maartje F. Hamers , Oliver Plümper , John W.M. Jagt , Martin Ziegler

Carbonate fossils from the Maastrichtian Type area offer important insights into climate dynamics across the Cretaceous/Paleogene boundary. While previous research has established the biostratigraphy and a carbon isotope-based geochronological timescale, allowing for global data comparison, constraints on the local seawater properties remain limited. Our study utilizes oxygen and carbon isotopes, as well as clumped isotope thermometry to reconstruct seawater temperature and its oxygen isotope composition based on carbonate fossil assemblages. Novel analyses of fossil echinoderms, brachiopods, gastropods, bivalves, bryozoans and existing studies were clustered according to their stratigraphy and show temperature fluctuations ranging between

{18.3}_{- 3.2}^{+ 3.4}

to

{22.7}_{- 4.9}^{+ 5.1}

°C (±95 % CI) that together with existing studies temporary match varying activity of Deccan Trap volcanism. The mean temperature estimate for the late Maastrichtian–early Danian of

{20.6}_{- 1.2}^{+ 1.2}

°C is slightly warmer than modern annual sea surface temperatures at the same latitude and in line with palaeoclimate simulations using 3 times the preindustrial atmospheric pCO₂ as model input. The oxygen isotope composition of the shallow sea environment fluctuate between

{0.3}_{- 0.9}^{+ 0.9}

to

{1.0}_{- 0.9}^{+ 1.0}

‰, together with existing data even to slightly negative values. These fluctuations reflect the highly dynamic hydrologic conditions linked to variations in the evaporation/precipitation budget, sea-level fluctuations and eventual changes in seawater circulation. This study on fossil assemblages from the Maastrichtian Type area shows the dynamic seawater conditions in shallow sea systems and the urgent need for higher spatial and subseasonal resolution when reconstructing regional climate conditions in epeiric marine environments.

来自马斯特里赫特类型地区的碳酸盐化石为白垩纪/古近纪边界的气候动力学提供了重要的见解。虽然以前的研究已经建立了生物地层学和基于碳同位素的年代学时间尺度，允许全球数据比较，但对局部海水性质的限制仍然有限。本研究基于碳酸盐化石组合，利用氧、碳同位素和团块同位素测温法重建海水温度及其氧同位素组成。对棘皮类、腕足类、腹足类、双壳类和苔藓虫化石的新分析和现有研究根据它们的地层聚集在一起，显示温度波动范围在18.3−3.2+3.4至22.7−4.9+5.1°C（±95% CI）之间，与现有研究暂时匹配德干圈闭火山活动的变化。马斯特里赫特晚期-大年早期的平均温度估计为20.6−1.2+1.2°C，略高于同一纬度的现代年海面温度，并且与使用3倍于工业化前大气二氧化碳分压作为模式输入的古气候模拟相一致。浅海环境氧同位素组成在0.3−0.9+0.9 ~ 1.0−0.9+1.0‰之间波动，与已有资料相结合甚至略为负值。这些波动反映了与蒸发/降水收支、海平面波动和海水环流最终变化有关的高度动态水文条件。通过对马斯特里赫特类型区域化石组合的研究，揭示了浅海系统的动态海水条件，以及在近海环境中重建区域气候条件时迫切需要更高的空间和亚季节分辨率。

{"title":"Seawater properties based on clumped isotope analyses of macrofossil assemblages from the Upper Cretaceous–lower Paleocene Type-Maastrichtian area","authors":"Inigo A. Müller , David Rijkes , Emily J. Judd , Maartje F. Hamers , Oliver Plümper , John W.M. Jagt , Martin Ziegler","doi":"10.1016/j.cretres.2025.106258","DOIUrl":"10.1016/j.cretres.2025.106258","url":null,"abstract":"<div><div>Carbonate fossils from the Maastrichtian Type area offer important insights into climate dynamics across the Cretaceous/Paleogene boundary. While previous research has established the biostratigraphy and a carbon isotope-based geochronological timescale, allowing for global data comparison, constraints on the local seawater properties remain limited. Our study utilizes oxygen and carbon isotopes, as well as clumped isotope thermometry to reconstruct seawater temperature and its oxygen isotope composition based on carbonate fossil assemblages. Novel analyses of fossil echinoderms, brachiopods, gastropods, bivalves, bryozoans and existing studies were clustered according to their stratigraphy and show temperature fluctuations ranging between <span><math><mrow><msubsup><mn>18.3</mn><mrow><mo>−</mo><mn>3.2</mn></mrow><mrow><mo>+</mo><mn>3.4</mn></mrow></msubsup></mrow></math></span> to <span><math><mrow><msubsup><mn>22.7</mn><mrow><mo>−</mo><mn>4.9</mn></mrow><mrow><mo>+</mo><mn>5.1</mn></mrow></msubsup></mrow></math></span> °C (±95 % CI) that together with existing studies temporary match varying activity of Deccan Trap volcanism. The mean temperature estimate for the late Maastrichtian–early Danian of <span><math><mrow><msubsup><mn>20.6</mn><mrow><mo>−</mo><mn>1.2</mn></mrow><mrow><mo>+</mo><mn>1.2</mn></mrow></msubsup></mrow></math></span> °C is slightly warmer than modern annual sea surface temperatures at the same latitude and in line with palaeoclimate simulations using 3 times the preindustrial atmospheric pCO<sub>2</sub> as model input. The oxygen isotope composition of the shallow sea environment fluctuate between <span><math><mrow><msubsup><mn>0.3</mn><mrow><mo>−</mo><mn>0.9</mn></mrow><mrow><mo>+</mo><mn>0.9</mn></mrow></msubsup></mrow></math></span> to <span><math><mrow><msubsup><mn>1.0</mn><mrow><mo>−</mo><mn>0.9</mn></mrow><mrow><mo>+</mo><mn>1.0</mn></mrow></msubsup></mrow></math></span>‰, together with existing data even to slightly negative values. These fluctuations reflect the highly dynamic hydrologic conditions linked to variations in the evaporation/precipitation budget, sea-level fluctuations and eventual changes in seawater circulation. This study on fossil assemblages from the Maastrichtian Type area shows the dynamic seawater conditions in shallow sea systems and the urgent need for higher spatial and subseasonal resolution when reconstructing regional climate conditions in epeiric marine environments.</div></div>","PeriodicalId":55207,"journal":{"name":"Cretaceous Research","volume":"179 ","pages":"Article 106258"},"PeriodicalIF":1.7,"publicationDate":"2025-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145466986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Agglutinated foraminifera and calcareous nannoplankton proxies for age determination and paleoenvironmental reconstruction of an Upper Cretaceous succession in the North Sudetic Cretaceous Basin (Germany) 德国北苏台德白垩世盆地上白垩世演替的凝集有孔虫和钙质纳米浮游生物代用物年龄测定和古环境重建

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-16 DOI: 10.1016/j.cretres.2025.106256

Richard M. Besen , Ramona Bălc , Mădălina-Elena Kallanxhi

The present study presents the findings of a comprehensive analysis of agglutinated foraminifera and calcareous nannoplankton from drill core Spremberg Cu Sp 101/6, situated within the North Sudetic Cretaceous Basin in Germany. These results provide refined biostratigraphic data and contribute to the paleoenvironmental reconstruction for both surface and bottom water conditions in the studied region.

Several calcareous nannoplankton taxa facilitated the identification of specific biozones, including Eiffellithus eximius (UC8), Micula staurophora (UC10), and Lithastrinus grillii (UC11). Notably, M. staurophora and L. grillii display significantly earlier occurrences when correlated with inoceramid zonation, indicating a diachronous first appearance of these taxa.

Using cluster analysis, principal component analysis, and taxonomical information, microfossil assemblages suggest that shallower, eutrophic conditions prevailed during the Cenomanian, whereas the Turonian was characterized by less diverse and poorly preserved assemblages. During the Coniacian, calcareous nannofossil assemblages indicate fluctuations between intervals of poor preservation and phases of increased assemblage diversity, probably associated with eutrophic conditions during the early Coniacian. This was followed by a transition to predominantly oligotrophic and deeper conditions during the middle to late Coniacian. Changes in the agglutinated foraminiferal assemblages likely reflect the grade of disturbance of bottom-water conditions mostly controlled by regional subsidence.

本文介绍了对德国北苏德海白垩纪盆地Spremberg Cu Sp 101/6钻孔岩心中凝集有孔虫和钙质纳米浮游生物的综合分析结果。这些结果提供了精细的生物地层资料，有助于研究区表层和底水条件的古环境重建。一些钙质纳米浮游生物分类有助于确定特定的生物带，包括Eiffellithus eximius （UC8）、Micula staurophora （UC10）和Lithastrinus grillii （UC11）。值得注意的是，M. staurophora和L. grillii的出现时间明显早于接种带，表明这两个分类群的首次出现具有历时性。利用聚类分析、主成分分析和分类信息，微化石组合表明，在塞诺曼期，较浅的富营养化条件占主导地位，而在Turonian，组合的多样性较少，保存较差。在Coniacian期间，钙质纳米化石组合表明在保存不良的间隔和组合多样性增加的阶段之间波动，可能与早期Coniacian的富营养化条件有关。随后在Coniacian中后期过渡到主要的少营养和更深的条件。凝集有孔虫组合的变化可能反映了主要受区域沉降控制的底水条件扰动程度。

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引用次数: 0

Macrofauna and stable isotope record of the Jurassic‒Cretaceous transition at the Dedina section (Golubac, eastern Serbia) 塞尔维亚东部Golubac Dedina剖面侏罗纪-白垩纪过渡时期的大型动物群及稳定同位素记录

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-15 DOI: 10.1016/j.cretres.2025.106250

Lucie Vaňková , Barbara V. Radulović , Martin Košťák , Dragoman Rabrenović , Martin Mazuch , Dejan Barjaktarović , Slađana Dušanić

The Tithonian‒Berriasian boundary interval at the Dedina section (Serbia) has been evaluated from the perspective of rare invertebrate fossils (excluding ammonites and their aptychi) and stable isotope data obtained from the bulk rock samples (δ¹³C_carb and δ¹⁸O_carb). The majority of the described benthic fauna consists of brachiopods (Lacunosella hoheneggeri, Tropeothyris tychaviensis, Svaljavithyris bilimeki and Helvetella arzierensis); additionally, a single bivalve species Camptonectes (Camptonectes) cottaldinus is present. This fauna occurs predominantly in the uppermost part of the section, corresponding to the middle Berriasian. Rare belemnites (genera Duvalia, Berriasibelus, Tithonobelus, and Hibolites) exhibit a faunal turnover around the boundary between the calpionellid Remaniella ferasini and Calpionella elliptica subzones, where the family Duvaliidae is largely replaced by Belemnopseidae. The stable carbon isotope data are consistent with previously published records from the north-western Tethys, showing typical slightly negative excursions and trends: at the base of the Calpionella alpina Subzone, within the Ferasini Subzone (a well documented negative δ¹³C_carb excursion), and a negative peak within the Elliptica Subzone. The latter may hold potential correlative value but this requires confirmation. The stable oxygen isotope data are more affected by diagenesis, but partially reflect trends observed in other sections and may therefore preserve a palaeoclimatic signal.

从稀有无脊椎动物化石（不包括菊石及其类）和块状岩石样品（δ13Ccarb和δ18Ocarb）的稳定同位素数据的角度对塞尔维亚Dedina剖面的Tithonian-Berriasian边界段进行了评价。所描述的底栖动物主要为腕足类动物（Lacunosella hoheneggeri, Tropeothyris tychaviensis， Svaljavithyris bilimeki和Helvetella arzierensis）；此外，存在单一双壳类Camptonectes (Camptonectes) cottaldinus。这种动物群主要出现在剖面的最上部，对应于贝里亚中部。稀有的蛭石属（Duvalia属，Berriasibelus属，Tithonobelus属和Hibolites属）在calpionellid Remaniella ferasini亚带和Calpionella elliptica亚带之间表现出动物群更替，其中duvalidae科大部分被Belemnopseidae取代。稳定碳同位素数据与先前发表的特提斯西北部记录一致，显示出典型的轻微负偏移和趋势：在Calpionella alpina亚带的底部，Ferasini亚带内（一个有充分记录的负δ13Ccarb偏移），以及椭圆亚带内的负峰。后者可能具有潜在的相关价值，但这需要确认。稳定氧同位素数据受成岩作用影响较大，但部分反映了其他剖面观测到的趋势，因此可能保留了古气候信号。

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引用次数: 0

Fish Faunas from the Bissekty Formation (Turonian), Uzbekistan: Insights into biogeographic connectivity and climate-driven Faunal Turnover 乌兹别克斯坦Bissekty组（Turonian）的鱼类动物群：对生物地理连通性和气候驱动的动物群更替的见解

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-15 DOI: 10.1016/j.cretres.2025.106252

Donald B. Brinkman , Martin Kundrát , David J. Ward , Alison M. Murray , Izzet K. Aimbetov , Lisa L. Van Loon , Neil R. Banerjee

The Bissekty Formation (Turonian, Uzbekistan) provides new insights into the reorganization of aquatic paleocommunities that occurred during the Turonian thermal maximum, a period of significant climatic and faunal change. The assemblage includes four basal neopterygians and 13 teleosts. Teleosts are dominated by members of early diverging lineages, including Ichthyodectiformes, Elopomorpha, Osteoglossiformes, and Clupeomorpha. More derived teleosts present in the assemblage includes a characiform and an acanthomorph. The assemblage is distinctive compared to Late Cretaceous assemblages from North America in the high abundance of ichthyodectiforms and elopomorphs and both high abundance and large size of acanthomorphs. The Bissekty fish assemblages differs from preceding Cenomanian assemblages of Laurasia in the absence of two taxa that were dominant in the earlier Cenomanian assemblages, Scheenstia López-Arbarello and Sferco, 2011 (Lepidotidae) and a pycnodont, and the appearance of seven new taxa. One of the newly appearing taxa is a member of Characiformes, a group that is thought to have originated in Gondwana, adding to the evidence that the introduction of new taxa was a result, in part, of intercontinental dispersal events. All seven of the taxa that first appear in the Bissekty Formation are closely related to, or indistinguishable from, taxa present in the North American portion of Laurasia. However, only two of these are known to occur in North America during the Turonian, with the remaining taxa first occurring in North America in a step-wise pattern during the Late Cretaceous. Conversely, two of the taxa that first occur in the Turonian of the North American portion of Laurasia are absent in Asian assemblages.

Bissekty组（Turonian, Uzbekistan）为研究发生在Turonian热极大期的水生古群落重组提供了新的见解，这是一个重大的气候和动物变化时期。该组合包括4种基翅类和13种硬骨鱼类。硬骨鱼主要是早期分化谱系的成员，包括鱼形目、鱼形目、骨舌形目和鱼形目。在组合中存在的更多衍生硬骨鱼包括特征鱼和棘形鱼。与北美晚白垩世的组合相比，该组合的特点是鱼形类和鱼形类丰度高，棘形类丰度高，尺寸大。Bissekty鱼类组合与Laurasia以前的Cenomanian组合的不同之处在于缺少两个在早期Cenomanian组合中占主导地位的分类群，Scheenstia López-Arbarello and Sferco, 2011（鳞翅目）和一个长齿鱼，并且出现了7个新的分类群。其中一个新出现的分类群是characterformes的成员，该分类群被认为起源于冈瓦纳，这进一步证明了新分类群的引入部分是洲际分散事件的结果。在Bissekty组首次出现的所有7个分类群都与月桂属北美部分的分类群密切相关或难以区分。然而，其中只有两个已知出现在北美的Turonian期间，其余的分类群在晚白垩纪期间以阶梯模式首次出现在北美。相反，在月牙亚属北美部分的土伦系中首次出现的两个分类群在亚洲的组合中却没有出现。

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引用次数: 0

Blooming under the shadow of Patagotitan mayorum: Early Cretaceous tiny flowers from Patagonia, Argentina 在巴塔哥尼亚的阴影下绽放：早白垩世的小花，来自阿根廷巴塔哥尼亚

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-14 DOI: 10.1016/j.cretres.2025.106254

Giovanni C. Nunes , Ignacio H. Escapa , Luis M. Sender , N. Rubén Cúneo , Maria A. Gandolfo

The fossil record of angiosperm reproductive remains from Lower Cretaceous deposits is critical for understanding angiosperm early evolution and rapid radiation. The fossil record of early flowers from the Southern Hemisphere is still extremely scarce compared to the Northern Hemisphere, particularly from outcrops located south of the Tropic of Capricorn. Here, we describe flowers from Upper Albian (101 Ma; Cerro Barcino Formation) deposits of Patagonia, Argentina, found in association with Patagotitan mayorum, the largest known dinosaur in the world at present. The flowers are pistillate, less than 10 mm in diameter, actinomorphic, pentamerous, and perigynous, with a tepaloid perianth, and are assigned to the new genus and species Patagoflora minima. This discovery represents the first Albian record of flowers for southern South America and one of the best-dated ones for Gondwana. Patagoflora minima is also one of the very few examples of flowers preserved along with dinosaurs. Its association with abundant and diverse angiosperm leaves and dinosaur remains provides significant data for understanding the ecosystems inhabited by the largest terrestrial animals that ever lived.

下白垩世被子植物生殖遗存的化石记录对了解被子植物的早期演化和快速辐射具有重要意义。与北半球相比，南半球早期花朵的化石记录仍然极其稀少，特别是在南回归线以南的露头。在这里，我们描述了来自阿根廷巴塔哥尼亚上Albian （101 Ma； Cerro Barcino组）矿床的花，这些花与目前世界上已知的最大的恐龙巴塔哥提龙mayorum有关。该花具雌蕊，直径小于10mm，辐射对称，五分生，周生，花被被片状，属于新属和新种Patagoflora minima。这一发现代表了南美洲南部的第一个阿尔比亚花记录，也是冈瓦纳最准确的时间记录之一。Patagoflora minima也是为数不多的与恐龙一起保存下来的花朵之一。它与丰富多样的被子植物叶片和恐龙遗骸的联系为了解曾经生活过的最大陆生动物所居住的生态系统提供了重要的数据。

{"title":"Blooming under the shadow of Patagotitan mayorum: Early Cretaceous tiny flowers from Patagonia, Argentina","authors":"Giovanni C. Nunes , Ignacio H. Escapa , Luis M. Sender , N. Rubén Cúneo , Maria A. Gandolfo","doi":"10.1016/j.cretres.2025.106254","DOIUrl":"10.1016/j.cretres.2025.106254","url":null,"abstract":"<div><div>The fossil record of angiosperm reproductive remains from Lower Cretaceous deposits is critical for understanding angiosperm early evolution and rapid radiation. The fossil record of early flowers from the Southern Hemisphere is still extremely scarce compared to the Northern Hemisphere, particularly from outcrops located south of the Tropic of Capricorn. Here, we describe flowers from Upper Albian (101 Ma; Cerro Barcino Formation) deposits of Patagonia, Argentina, found in association with <em>Patagotitan mayorum</em>, the largest known dinosaur in the world at present. The flowers are pistillate, less than 10 mm in diameter, actinomorphic, pentamerous, and perigynous, with a tepaloid perianth, and are assigned to the new genus and species <em>Patagoflora minima</em>. This discovery represents the first Albian record of flowers for southern South America and one of the best-dated ones for Gondwana. <em>Patagoflora minima</em> is also one of the very few examples of flowers preserved along with dinosaurs. Its association with abundant and diverse angiosperm leaves and dinosaur remains provides significant data for understanding the ecosystems inhabited by the largest terrestrial animals that ever lived.</div></div>","PeriodicalId":55207,"journal":{"name":"Cretaceous Research","volume":"179 ","pages":"Article 106254"},"PeriodicalIF":1.7,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145418136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Diagenetic characterization of crocodyliform fossils from the Adamantina Formation (Upper Cretaceous, Bauru Group): Evaluating the chemical alteration of skeletal tissues through a multi-technique approach 上白垩统Bauru群Adamantina组鳄鱼形化石的成岩特征：通过多技术方法评估骨骼组织的化学变化

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-14 DOI: 10.1016/j.cretres.2025.106248

Fellipe P. Muniz , Annie Schmaltz Hsiou , Fabio Dias de Andrade , Gabriel Ladeira Osés , Márcia A. Rizzutto , Mírian Liza Alves Forancelli Pacheco

The Adamantina Formation hosts one of the most well-documented Late Cretaceous continental faunas in South America, with crocodyliforms standing out for their unusual richness and ecomorphological diversity. While their taxonomy and anatomy have been widely studied, the understanding of their fossilization processes has been largely overlooked. Here, we apply a multi-technique approach to analyze diagenetic alterations of the skeletal elements of crocodyliforms from the Adamantina Formation, combining information from energy dispersive X-ray fluorescence, scanning electron microscopy with energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, and X-ray diffraction. Our results indicate significant structural and compositional changes, including loss of the organic matrix, void permineralization, ionic substitutions, and recrystallization. Although organic molecules were not unambiguously detected, some Raman spectra exhibited bands in the 1000–1800 cm⁻¹ range that resemble signals previously linked to organic compounds, but which may instead result from fluorescence induced by rare earth elements. Void-filling minerals reflect the prevailing influence of both alkaline (e.g., calcite, relict siderite) and oxidizing (iron oxyhydroxides) pore waters. All samples showed transformation of the original bioapatite into carbonated fluorapatite, highlighting the importance of the precipitation of a more thermodynamically stable phase for the long-term survival of skeletal remains. Raman spectroscopy further revealed differences in fossil apatite preservation among samples, with some showing less alteration and potentially storing original chemical information. The combination of techniques used in this study allowed a comprehensive assessment of the mode and degree of diagenetic alteration of crocodyliform remains, which might be useful when selecting samples for molecular or isotopic studies.

Adamantina组拥有南美洲记录最完整的晚白垩世大陆动物群之一，鳄鱼类以其不同寻常的丰富性和生态形态多样性而脱颖而出。虽然它们的分类学和解剖学已经被广泛研究，但对它们的石化过程的理解在很大程度上被忽视了。本文采用多技术方法，结合能量色散x射线荧光、扫描电镜与能量色散x射线能谱、微拉曼光谱和x射线衍射等信息，分析了Adamantina组鳄鱼形化石骨骼元素的成岩变化。我们的结果表明了显著的结构和组成变化，包括有机基质的损失，空隙过矿化，离子取代和再结晶。虽然有机分子没有被明确地检测到，但一些拉曼光谱在1000-1800 cm−1范围内显示出类似于以前与有机化合物相关的信号，但这可能是由稀土元素诱导的荧光引起的。填空矿物反映了碱性（如方解石、残余菱铁矿）和氧化性（氧化铁）孔隙水的普遍影响。所有样品都显示原始生物磷灰石转变为碳化氟磷灰石，强调了更热动力学稳定阶段的沉淀对骨骼遗骸长期存活的重要性。拉曼光谱进一步揭示了不同样品中化石磷灰石保存的差异，有些样品显示较少的蚀变，可能储存了原始的化学信息。本研究中使用的技术组合允许对鳄鱼形遗骸的成岩改变模式和程度进行全面评估，这可能在选择分子或同位素研究样本时有用。

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引用次数: 0

A first fossil sturgeon from the Upper Cretaceous (Maastrichtian) of Northwestern Pacific 西北太平洋上白垩纪（马斯特里赫特）的第一具鲟鱼化石

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-10-14 DOI: 10.1016/j.cretres.2025.106251

Shinya Miyata , Yasuhisa Nakajima , Isao Motoyama , Tomohiro Nishimura , Yoshitaka Yabumoto

This paper reports a detailed description of a single acipenserid subopercle from the Maastrichtian Hakobuchi Formation, Yezo Group, Hokkaido, Japan. The specimen has a nearly circular fan shape. Anterior extension and lateral surface ornamentation are observed. These characteristics are similar to those in representatives of the family Acipenseridae among Acipenseriformes. Additionally, the size of the subopercle is more than 15 cm, which leads to an estimated total length of more than 180 cm. This is the first occurrence of sturgeons from the Maastrichtian of East Asia; it reveals the presence of acipenserids in the northwestern Pacific region during the Late Cretaceous. This study also provides new insights into the North American–Asian dispersal route of sturgeons in the Cretaceous.

本文报道了在日本北海道Yezo群Maastrichtian Hakobuchi组中发现的单个蛇尾纲亚环的详细描述。样品呈近似圆形的扇形。观察到前伸和外侧表面纹饰。这些特征类似于那些代表家庭的鲟科鲟目之一。此外，亚环的大小超过15厘米，这导致估计的总长度超过180厘米。这是东亚马斯特里赫特群岛首次出现鲟鱼；它揭示了晚白垩纪西北太平洋地区出现的蛇尾纲动物。该研究也为白垩纪鲟鱼在北美-亚洲的传播路线提供了新的见解。

引用次数: 0