Cretaceous Research最新文献_第6页

Paleoenvironmental evolution and sequence stratigraphic reconstruction during the Late Cretaceous in southern Egypt: Implications for palynological and geochemical proxy data 埃及南部晚白垩世古环境演化和层序地层重建：孢粉学和地球化学代用资料的意义

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-09-17 DOI: 10.1016/j.cretres.2025.106239

Abdallah Rabea , Omar Mohamed , Ahmed Mansour , Ramadan S. Mohamed , Ahmed Ali

During the Campanian-Maastrichtian, long-term cooling drove eustatic sea-level fall, promoting carbonate platform deposition at mid-to-high paleolatitudes. Here, 85 rock samples were collected from the Campanian-Maastrichtian uppermost Qusseir, Duwi, and lowermost Dakhla formations at three sections in the El-Sebaiya area of the Nile Valley (Egypt). A comprehensive approach, including palynological, whole rock geochemistry, and total organic carbon (TOC) analyses, was performed. Four palynofacies assemblages (PFA) were identified in the three sections. PFA-A shows high abundances of amorphous organic matter (AOM), suggesting deposition in a shallow marine environment, whereas PFA-B exhibits moderate abundances of phytoclasts and AOM, indicative of deposition in fluvio-deltaic to marginal shallow marine conditions. PFA-C is dominated by phytoclasts, mainly of opaque equidimensional particles, characterizing a fluvio-deltaic environment, while PFA-D is characterized by moderate levels of AOM and dinoflagellate cysts (dinocysts) with low phytoclasts, pointing to a shallow marine shelf environment. Dinocysts are dominated by peridinioid forms combined with the common distribution of phosphorite belts, reflecting that the southern Tethys was controlled by upwelling-driven elevated productivity settings under varying redox conditions. Data further allowed the reconstruction of three third-order transgressive-regressive sequences. The transgressive systems tract (TST) sediments are characterized by an increase in AOM, coincided with elevated carbonate content, Mn, and Mn/Al ratios, with maxima corresponding to the maximum flooding surface (MFS) within most sequences. Conversely, the regressive systems tract (RST) sediments show an increase in phytoclasts and elevated SiO₂, Zr, Zr/Al, Ti, Ti/Al, and Sr/Ca ratios, with their highest values corresponding to the maximum regressive surface (MRS).

在坎帕尼亚-马斯特里赫特时期，长期的降温导致海平面上升下降，促进了古中高纬度碳酸盐台地沉积。在这里，从尼罗河流域（埃及）El-Sebaiya地区的坎帕尼亚-马strichtian最上层的Qusseir， Duwi和最下层的Dakhla地层中收集了85个岩石样本。采用了包括孢粉学、全岩石地球化学和总有机碳（TOC）分析在内的综合方法。在3个剖面中确定了4个孢粉相组合。PFA-A显示出高丰度的无定形有机物（AOM），表明沉积于浅海环境，而PFA-B显示出中等丰度的植物碎屑和AOM，表明沉积于河流三角洲至边缘浅海环境。PFA-C以植物碎屑为主，主要为不透明等维颗粒，具有河流三角洲环境特征，而PFA-D以中等水平的AOM和低植物碎屑的甲藻囊（dinocysts）为特征，表明浅海陆架环境。生物囊以类橄榄石形态为主，并结合磷矿带的普遍分布，反映了特提斯南部受上升流驱动的不同氧化还原条件下的高生产力环境控制。数据进一步允许重建三个三阶海侵回归序列。海侵体系域（TST）沉积物的特征是AOM增加，碳酸盐含量、Mn和Mn/Al比值升高，最大值对应大多数层序的最大泛洪面（MFS）。相反，退退体系域（RST）沉积物中植物碎屑增加，SiO2、Zr、Zr/Al、Ti、Ti/Al和Sr/Ca比值升高，其最大值对应最大退退面（MRS）。

{"title":"Paleoenvironmental evolution and sequence stratigraphic reconstruction during the Late Cretaceous in southern Egypt: Implications for palynological and geochemical proxy data","authors":"Abdallah Rabea , Omar Mohamed , Ahmed Mansour , Ramadan S. Mohamed , Ahmed Ali","doi":"10.1016/j.cretres.2025.106239","DOIUrl":"10.1016/j.cretres.2025.106239","url":null,"abstract":"<div><div>During the Campanian-Maastrichtian, long-term cooling drove eustatic sea-level fall, promoting carbonate platform deposition at mid-to-high paleolatitudes. Here, 85 rock samples were collected from the Campanian-Maastrichtian uppermost Qusseir, Duwi, and lowermost Dakhla formations at three sections in the El-Sebaiya area of the Nile Valley (Egypt). A comprehensive approach, including palynological, whole rock geochemistry, and total organic carbon (TOC) analyses, was performed. Four palynofacies assemblages (PFA) were identified in the three sections. PFA-A shows high abundances of amorphous organic matter (AOM), suggesting deposition in a shallow marine environment, whereas PFA-B exhibits moderate abundances of phytoclasts and AOM, indicative of deposition in fluvio-deltaic to marginal shallow marine conditions. PFA-C is dominated by phytoclasts, mainly of opaque equidimensional particles, characterizing a fluvio-deltaic environment, while PFA-D is characterized by moderate levels of AOM and dinoflagellate cysts (dinocysts) with low phytoclasts, pointing to a shallow marine shelf environment. Dinocysts are dominated by peridinioid forms combined with the common distribution of phosphorite belts, reflecting that the southern Tethys was controlled by upwelling-driven elevated productivity settings under varying redox conditions. Data further allowed the reconstruction of three third-order transgressive-regressive sequences. The transgressive systems tract (TST) sediments are characterized by an increase in AOM, coincided with elevated carbonate content, Mn, and Mn/Al ratios, with maxima corresponding to the maximum flooding surface (MFS) within most sequences. Conversely, the regressive systems tract (RST) sediments show an increase in phytoclasts and elevated SiO<sub>2</sub>, Zr, Zr/Al, Ti, Ti/Al, and Sr/Ca ratios, with their highest values corresponding to the maximum regressive surface (MRS).</div></div>","PeriodicalId":55207,"journal":{"name":"Cretaceous Research","volume":"178 ","pages":"Article 106239"},"PeriodicalIF":1.7,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159476","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

First reports of a probable ankylosaurian (Thyreophora) trackway from the Jindong Formation (Cenomanian) of Goseong County, South Korea 在韩国高城郡金洞组（Cenomanian）首次发现可能的甲龙（Thyreophora）足迹

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-09-17 DOI: 10.1016/j.cretres.2025.106240

Han Sang Yoon , Hyun Wook Kim , Jin-Young Park , Seung-Ho Jung , Dal-Yong Kong , Yuong-Nam Lee

A quadrupedal trackway (GS-BHG 2) reported from the Bonghwa-gol tracksite of the Upper Cretaceous Jindong Formation (Cenomanian) shows morphological differences from other dinosaur ichnotaxa from South Korea and other Asian countries. The trackway GS-BHG 2 is characterized by an elongated pes with three short, blunt, and straight digits and oval-to kidney-shaped manus without discernible digit traces showing low heteropody and wide trackway gauge. Based on its morphological characteristics and the temporal distribution of dinosaur fauna during the ‘mid’-Cretaceous, the trackmaker of GS-BHG 2 is tentatively assigned as an ankylosaurid dinosaur, and we refer this trackway as cf. Ruopodosaurus. Pes tracks of GS-BHG 2 show differential depth in their medial and lateral parts, implying that the pressure was focused on the medial part of the pedes during locomotion.

在白垩统上白垩统金洞组（Cenomanian）奉花金足迹遗址发现的四足恐龙足迹（GS-BHG 2）与韩国和亚洲其他国家发现的恐龙化石在形态上存在差异。轨道GS-BHG 2的特点是细长的类型，有三个短，钝，直的手指和椭圆形至肾形的手，没有明显的手指痕迹，显示低异足和宽轨道轨距。根据GS-BHG 2脚印的形态特征和恐龙区系在“中”白垩纪的时间分布，初步确定GS-BHG 2脚印为甲龙，并将其命名为若opodosaurus。GS-BHG 2的足径内侧和外侧深度不同，说明运动时压力主要集中在足径内侧。

引用次数: 0

Evidence of large pliosaurids in the late Valanginian of Colombia 哥伦比亚瓦兰吉尼亚晚期大型上龙的证据

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-09-15 DOI: 10.1016/j.cretres.2025.106235

Javier García-Guerrero , Fredy Parra Ruge , German A. Prieto , Edwin-Alberto Cadena

The fossil record of Lower Cretaceous pliosaurids, particularly from the Valanginian is still poorly known globally, hindering efforts to reconstruct their evolution and palaeogeographical distribution within a broader time frame. Here, we describe an isolated cervical centrum (14 cm maximum diameter) of a pliosaurid belonging to a Brachaucheniinae gen. et sp. indet., from the Lower Cretaceous (upper Valanginian) Rosa Blanca Formation in Zapatoca, Colombia. The presence of large brachaucheniines in the Rosa Blanca Formation suggests that these large pliosaurids were part of the abundant and diverse fauna that inhabited the northwestern margin of Gondwana during the Early Cretaceous and extends their record in northern South America from the Barremian to the late Valanginian. These pliosaurids potentially acted as top predators in the food chain of lower latitude shallow marine environments. This discovery contributes new data to the taxonomic and chronostratigraphic framework of Early Cretaceous marine reptiles from the Proto-Caribbean domain.

下白垩纪上龙的化石记录，特别是来自Valanginian的化石记录，在全球范围内仍然知之甚少，这阻碍了在更广泛的时间框架内重建它们的进化和古地理分布的努力。在这里，我们描述了一个分离的颈椎体（最大直径14厘米），属于brachacheniinae gen. et sp. indet的上龙。来自哥伦比亚萨帕托卡的下白垩纪（上瓦兰吉尼亚）Rosa Blanca组。Rosa Blanca组中大型brachacheniines的存在表明，这些大型上龙是早白垩纪时期居住在冈瓦纳西北边缘的丰富多样的动物群的一部分，并将其在南美洲北部的记录从巴雷米亚延伸到晚瓦兰吉尼亚。这些上龙有可能成为低纬度浅海环境食物链中的顶级捕食者。这一发现为原加勒比海地区早白垩世海生爬行动物的分类和年代地层格架提供了新的数据。

引用次数: 0

A new amber Lagerstätte from the Lower Cretaceous of Japan 日本下白垩纪发现的新琥珀Lagerstätte

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-09-15 DOI: 10.1016/j.cretres.2025.106236

Aya Kubota , Ryo Taniguchi , Yoshinori Hikida , Yasuhiro Iba

During the Early Cretaceous, terrestrial ecosystems underwent a critical transition driven by the emergence and diversification of angiosperms. Amber-rich deposits from this period are crucial for understanding the diversity, interactions, and evolution of terrestrial biota. However, their occurrences are limited both geographically and stratigraphically. Here, we report a new amber Lagerstätte from the upper Aptian (116–114 Ma) in northern Hokkaido, Japan. The abundant amber occurs within deep-sea deposits and is rich in bio-inclusions: arthropods (hymenopterans, mites), fungi, and plant remains (tracheids, stellate hairs, pollen grains), with submicron-scale morphological details. This is the first report of fossiliferous amber-rich deposits from the Aptian in Asia. It is also recognized as one of the older amber-rich localities with bio-inclusions following those in northeastern Italy (Carnian, Upper Triassic), the Levantine area (Tithonian, Upper Jurassic; Barremian), Austria (Hauterivian), the United Kingdom (lower Barremian), and southern Congo (upper Aptian). This finding fills a paleobiogeographical gap in fossil record and provides anatomical and ecological insights into a critical interval marked by the rise of modern-type forest ecosystems.

在白垩纪早期，被子植物的出现和多样化推动了陆地生态系统的关键转变。这一时期的富含琥珀的沉积物对了解陆地生物群的多样性、相互作用和进化至关重要。然而，它们的出现在地理和地层上都是有限的。本文报道了在日本北海道北部Aptian上（116-114 Ma）发现的一种新琥珀Lagerstätte。丰富的琥珀存在于深海沉积物中，富含生物包裹体：节肢动物（膜翅目动物、螨虫）、真菌和植物遗骸（管状体、星状毛、花粉粒），具有亚微米尺度的形态细节。这是亚洲阿普tian地区首次发现富含琥珀的化石矿床。它也被认为是继意大利东北部（卡尼期，上三叠世），地中海地区（梯东期，上侏罗纪，巴雷米期），奥地利（Hauterivian），英国（下巴雷米期）和刚果南部（上阿普tian）之后最古老的富含琥珀的地区之一。这一发现填补了化石记录中的古生物地理学空白，并为现代森林生态系统兴起的关键时期提供了解剖学和生态学的见解。

{"title":"A new amber Lagerstätte from the Lower Cretaceous of Japan","authors":"Aya Kubota , Ryo Taniguchi , Yoshinori Hikida , Yasuhiro Iba","doi":"10.1016/j.cretres.2025.106236","DOIUrl":"10.1016/j.cretres.2025.106236","url":null,"abstract":"<div><div>During the Early Cretaceous, terrestrial ecosystems underwent a critical transition driven by the emergence and diversification of angiosperms. Amber-rich deposits from this period are crucial for understanding the diversity, interactions, and evolution of terrestrial biota. However, their occurrences are limited both geographically and stratigraphically. Here, we report a new amber Lagerstätte from the upper Aptian (116–114 Ma) in northern Hokkaido, Japan. The abundant amber occurs within deep-sea deposits and is rich in bio-inclusions: arthropods (hymenopterans, mites), fungi, and plant remains (tracheids, stellate hairs, pollen grains), with submicron-scale morphological details. This is the first report of fossiliferous amber-rich deposits from the Aptian in Asia. It is also recognized as one of the older amber-rich localities with bio-inclusions following those in northeastern Italy (Carnian, Upper Triassic), the Levantine area (Tithonian, Upper Jurassic; Barremian), Austria (Hauterivian), the United Kingdom (lower Barremian), and southern Congo (upper Aptian). This finding fills a paleobiogeographical gap in fossil record and provides anatomical and ecological insights into a critical interval marked by the rise of modern-type forest ecosystems.</div></div>","PeriodicalId":55207,"journal":{"name":"Cretaceous Research","volume":"178 ","pages":"Article 106236"},"PeriodicalIF":1.7,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159475","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

New ephialtitid wasps (Hymenoptera) of the Early Cretaceous Jehol Biota from NE China 中国东北早白垩世热河生物群中蜂类新种（膜翅目）

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-09-13 DOI: 10.1016/j.cretres.2025.106234

Ning Jia , Qi Zhang , Haichun Zhang

The Jurassic-Early Cretaceous family Ephialtitidae is considered as one of the most basal lineages of Apocrita, one of two suborders of the insect order Hymenoptera. Herein three genera and three species, of which one genus and three species are recognized as new to science, are described and illustrated from the Jianshangou Bed of the lower Yixian Formation of western Liaoning, NE China, including Tuphephialtites wangi sp. nov., Crephanogaster beipiaoensis sp. nov., and Chorephialtites longispinus gen. et sp. nov. So far a total of three genera and five species within the subfamily Ephialtitinae are known from the middle Jehol Biota in NE China, suggesting a high morphological disparity of Ephialtitidae during the Early Cretaceous in NE China. Occurrence of Crephanogaster Rasnitsyn, 1990 in both the Turga Formation of Transbaikalia, Russia and the Yixian Formation of NE China confirms these two formations are of coeval deposits. Additionally, a key to the genera of Ephialtitinae is given.

叶蜂科是膜翅目昆虫的两个亚目之一，是膜翅目昆虫中最基础的分支之一。这里3属3种,其中一个属和三个物种被认为是新的科学,描述和插图尖山沟黟县形成西方的辽宁、东北中国,包括Tuphephialtites不多sp. 11月,Crephanogaster beipiaoensis sp. 11月,和Chorephialtites longispinus将军等sp. 11月到目前为止共3属5种亚科内Ephialtitinae被从中间热河生物群在中国东北,表明早白垩世在中国东北地区有很高的形态差异。1990年在俄罗斯外贝加尔湖图尔加组和中国东北义县组均发现拉斯尼琴Crephanogaster Rasnitsyn，证实了这两个组为同时期沉积。此外，还给出了一种属的钥匙。

引用次数: 0

Calcareous nannofossil biostratigraphy of the upper Cretaceous to lower Paleocene in Zagros Basin, western Iran 伊朗西部扎格罗斯盆地上白垩统—下古新统钙质纳米化石生物地层学

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-09-03 DOI: 10.1016/j.cretres.2025.106213

Noushin Moradi Lirkashasi , Sakineh Arefifard , Thomas J. Algeo , Jonathan D. Schueth

Calcareous nannofossil biostratigraphy has been investigated for Upper Cretaceous and lowermost Paleocene deposits in the Garab section located on the northeastern limb of the Kabir Kuh Anticline, Zagros Basin (Iran). The results reveal a relatively complete record that spans the Cenomanian to Danian stages. The base of the section contains Eiffellithus turriseiffelii, implying placement in or above the UC0 Biozone, and the occurrence of Corollithion kennedyi at 68.8 m confirms placement in the Cenomanian. An unconformity is suggested by the missing UC15a-b Biozone in the upper Campanian Gurpi Formation. The Cenomanian/Turonian Boundary (CTB) and Oceanic Anoxic Event 2 (OAE2) is characterized by abundant small taxa including Biscutum constans, Discorhabdus ignotus, and Zeugrhabdotus noeliae, among which the last two taxa are indicators of surface-water fertility during OAE2. The Cretaceous/Paleogene Boundary (KPB) is marked by an increase of abundance of calcareous nannofossils such as Braarudosphaera bigelowii and Neobiscutum spp. and a rapid increase of calcareous dinoflagellates. Our results document high nannofossil productivity during the OAE2, as observed in other Tethyan locations, and rapid turnover and proliferation of disaster taxa such as Braarudosphaera bigelowii, and Neobiscutum spp. at the KPB. These results significantly enhance our understanding of these geological events and suggest that the Garab section is a strong candidate for further study of both the Cenomanian/Turonian boundary and K/Pg boundary.

对伊朗Zagros盆地Kabir Kuh背斜东北翼Garab剖面上白垩统和下古新统钙质纳米化石生物地层学进行了研究。结果显示了一个相对完整的记录，跨越了塞诺曼尼亚到丹尼尼亚阶段。该剖面底部含有艾菲ellithus turriseiffelii，表明其位于UC0生物带或以上，而在68.8 m处出现的corollithon kennedyi证实其位于Cenomanian。上坎帕统古尔皮组缺少UC15a-b生物带，提示不整合。Cenomanian/Turonian Boundary （CTB）和Oceanic Anoxic Event 2 （OAE2）的特征是存在大量的小类群，包括brustum constans、Discorhabdus ignotus和Zeugrhabdotus noeliae，其中后两个类群是OAE2期间地表水肥沃度的指标。白垩纪-古近纪界线（KPB）以brarudosphaera bigelowii和Neobiscutum sp.等钙质纳米化石的丰度增加和钙质鞭毛藻的快速增加为标志。我们的研究结果表明，在其他特提斯地区观察到的OAE2期间，纳米化石的生产力很高，KPB的灾难分类群（如Braarudosphaera bigelowii和Neobiscutum spp.）的更替和增殖也很快。这些结果大大提高了我们对这些地质事件的认识，并表明Garab剖面是进一步研究Cenomanian/Turonian边界和K/Pg边界的有力候选者。

{"title":"Calcareous nannofossil biostratigraphy of the upper Cretaceous to lower Paleocene in Zagros Basin, western Iran","authors":"Noushin Moradi Lirkashasi , Sakineh Arefifard , Thomas J. Algeo , Jonathan D. Schueth","doi":"10.1016/j.cretres.2025.106213","DOIUrl":"10.1016/j.cretres.2025.106213","url":null,"abstract":"<div><div>Calcareous nannofossil biostratigraphy has been investigated for Upper Cretaceous and lowermost Paleocene deposits in the Garab section located on the northeastern limb of the Kabir Kuh Anticline, Zagros Basin (Iran). The results reveal a relatively complete record that spans the Cenomanian to Danian stages. The base of the section contains <em>Eiffellithus turriseiffelii</em>, implying placement in or above the UC0 Biozone, and the occurrence of <em>Corollithion kennedyi</em> at 68.8 m confirms placement in the Cenomanian. An unconformity is suggested by the missing UC15a-b Biozone in the upper Campanian Gurpi Formation. The Cenomanian/Turonian Boundary (CTB) and Oceanic Anoxic Event 2 (OAE2) is characterized by abundant small taxa including <em>Biscutum constans</em>, <em>Discorhabdus ignotus</em>, and <em>Zeugrhabdotus noeliae</em>, among which the last two taxa are indicators of surface-water fertility during OAE2. The Cretaceous/Paleogene Boundary (KPB) is marked by an increase of abundance of calcareous nannofossils such as <em>Braarudosphaera bigelowii</em> and <em>Neobiscutum</em> spp. and a rapid increase of calcareous dinoflagellates. Our results document high nannofossil productivity during the OAE2, as observed in other Tethyan locations, and rapid turnover and proliferation of disaster taxa such as <em>Braarudosphaera bigelowii</em>, and <em>Neobiscutum</em> spp. at the KPB. These results significantly enhance our understanding of these geological events and suggest that the Garab section is a strong candidate for further study of both the Cenomanian/Turonian boundary and K/Pg boundary.</div></div>","PeriodicalId":55207,"journal":{"name":"Cretaceous Research","volume":"178 ","pages":"Article 106213"},"PeriodicalIF":1.7,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145057343","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

Vegetation and climate during the primary formation of the Songliao Basin, NE China 松辽盆地初生期的植被与气候

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-09-03 DOI: 10.1016/j.cretres.2025.106217

Miaoqin Lin , Jianguo Li , Yixiao Wu , Tan Tan , Yigang Xu

The International Continental Scientific Drilling Project (ICDP) in the Songliao Basin that has produced a continuous core of the Lower Cretaceous in 4134.81 m thickness, i.e. the SK-II borehole, provides an exceptional archive for studying tectonic and palaeoenvironmental history of the basin under the Cretaceous greenhouse climate. The Shahezi Formation that consists of the main part of this core, represents the primary basin fills at the syn-rift stage of the Songliao Basin and thus marks its commencement and is crucial for studying the timing and mechanism of this basin's early evolution. The precise age of the Shahezi Formation, however, remains controversial and little is known about the palaeovegetation and palaeoenvironment during its deposition. In this study, plenty of pollen and spores are extracted from core samples near the base of the Shahezi Formation. They are the oldest fossils so-far identified from the SK-Ⅱ borehole. The high abundance and diversity of Cicatricosisporites, in association with some other fossils as Pilosisporites, indicate a clear early–middle Aptian age for the base of the Shahezi Formation, i.e. the primary formation of the Songliao Basin. The vegetation was overall featured by abundant ferns, common cycads and some bryophytes in the ground storey, alongside conifer trees or shrubs of Pinaceae, Taxodiaceae, Araucariaceae and Cheirolepidiaceae in the upper canopy, with increases of Cheirolepidiaceae and cycads over time. A generally warm and humid tropical to subtropical climate with a trend to be slightly drier was developed, which might be a response of terrestrial ecosystem to the Oceanic Anoxic Event 1a.

国际大陆科学钻探项目（ICDP）在松辽盆地取得了厚度为4134.81 m的下白垩统连续岩心SK-II钻孔，为研究该盆地在白垩系温室气候下的构造和古环境史提供了一个独特的档案。该岩心的主体沙河子组代表了松辽盆地同裂谷期的主要盆地充填，标志着松辽盆地的开始，对研究松辽盆地早期演化的时间和机制具有重要意义。然而，沙河子组的确切年代仍有争议，对其沉积时期的古植被和古环境知之甚少。本研究从沙河子组底部附近的岩心样品中提取了大量的花粉和孢子。它们是迄今为止在SK-Ⅱ钻孔中发现的最古老的化石。cicatricosporites的高丰度和多样性，与其他一些化石（如Pilosisporites）相结合，表明松辽盆地沙河子组基底明显处于早-中阿普tian时代，即原始地层。植被总体上以地面层丰富的蕨类植物、普通苏铁和部分苔藓植物为特征，上层林冠层有松科、红杉科、云杉科和铁杉科的针叶乔木或灌木，随着时间的推移，铁杉科和铁杉科的数量有所增加。形成了温暖湿润的热带—亚热带气候，并有偏干燥的趋势，这可能是陆地生态系统对海洋缺氧事件1a的响应。

{"title":"Vegetation and climate during the primary formation of the Songliao Basin, NE China","authors":"Miaoqin Lin , Jianguo Li , Yixiao Wu , Tan Tan , Yigang Xu","doi":"10.1016/j.cretres.2025.106217","DOIUrl":"10.1016/j.cretres.2025.106217","url":null,"abstract":"<div><div>The International Continental Scientific Drilling Project (ICDP) in the Songliao Basin that has produced a continuous core of the Lower Cretaceous in 4134.81 m thickness, i.e. the SK-II borehole, provides an exceptional archive for studying tectonic and palaeoenvironmental history of the basin under the Cretaceous greenhouse climate. The Shahezi Formation that consists of the main part of this core, represents the primary basin fills at the syn-rift stage of the Songliao Basin and thus marks its commencement and is crucial for studying the timing and mechanism of this basin's early evolution. The precise age of the Shahezi Formation, however, remains controversial and little is known about the palaeovegetation and palaeoenvironment during its deposition. In this study, plenty of pollen and spores are extracted from core samples near the base of the Shahezi Formation. They are the oldest fossils so-far identified from the SK-Ⅱ borehole. The high abundance and diversity of <em>Cicatricosisporites</em>, in association with some other fossils as <em>Pilosisporites</em>, indicate a clear early–middle Aptian age for the base of the Shahezi Formation, i.e. the primary formation of the Songliao Basin. The vegetation was overall featured by abundant ferns, common cycads and some bryophytes in the ground storey, alongside conifer trees or shrubs of Pinaceae, Taxodiaceae, Araucariaceae and Cheirolepidiaceae in the upper canopy, with increases of Cheirolepidiaceae and cycads over time. A generally warm and humid tropical to subtropical climate with a trend to be slightly drier was developed, which might be a response of terrestrial ecosystem to the Oceanic Anoxic Event 1a.</div></div>","PeriodicalId":55207,"journal":{"name":"Cretaceous Research","volume":"178 ","pages":"Article 106217"},"PeriodicalIF":1.7,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145107828","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

New fossil notostracans (Branchiopoda, Notostraca) from the Lower Cretaceous of Inner Mongolia, China 内蒙古下白垩世notostracans新化石（鳃足目，Notostraca）

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-09-02 DOI: 10.1016/j.cretres.2025.106216

Wei-Wei Wang , Dong Ren , Zhi-Peng Zhao

Nototracans have lived on Earth for over 350 million years, yet limited species records and poor specimen preservation have significantly impeded our understanding of their early evolutionary history. Herein, we supplement the information of a known species and report a new species, Weichangiops trangularis Yang and Hong, 1980 and Weichangiops squamosus sp. nov., from the Lower Cretaceous Yixian Formation in Duolun, Inner Mongolia, China. The diagnosis characters of Weichangiops Yang and Hong, 1980 and W. trangularis were revised based on the new well-preserved specimens. These newly discovered fossil specimens allow for a detailed summary of morphological characteristics in Notostraca, with a systematic review of features observed in Cretaceous lineages. Given the relatively rarity of Cretaceous notostracan fossils, these findings not only expand the known species diversity of this period but also provide valuable insights into the early evolutionary processes of Notostraca.

Nototracans已经在地球上生活了3.5亿多年,但有限的物种记录和可怜的标本保存大大阻碍了我们对他们早期的进化历史的理解。本文补充了内蒙古多伦地区下白垩统易县组已知种的资料，并报道了Weichangiops trangularis Yang和Hong， 1980和Weichangiops squamosus sp. nov.的新种。根据保存完好的新标本，对Weichangiops Yang和Hong， 1980和W. trangularis的诊断特征进行了修订。这些新发现的化石标本使我们能够对Notostraca的形态特征进行详细的总结，并对白垩纪谱系中观察到的特征进行系统的回顾。考虑到白垩纪notostracan化石的相对稀罕性，这些发现不仅扩大了这一时期已知物种的多样性，而且为Notostraca的早期进化过程提供了有价值的见解。

引用次数: 0

Foraminifera and ostracod biostratigraphy of the English Coniacian – Campanian (Upper Cretaceous) Chalk: New results from Seaford Head and correlation to Eastern Europe 英国Coniacian - Campanian（上白垩世）白垩系有孔虫和介形虫生物地层：来自seford Head的新结果和与东欧的对比

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-08-30 DOI: 10.1016/j.cretres.2025.106215

Ian Jarvis , Zofia Dubicka , Markéta Chroustová

The uppermost Turonian – lower Campanian Chalk succession at Seaford Head, southern England, is described and the placement of stage and substage boundaries are defined. Previous studies of foraminifera and ostracods in the section are reviewed. New data are provided for 99 samples spanning the full exposed section. Samples yielded abundant well-preserved diverse microfossil assemblages. The stratigraphic distributions of 38 selected stratigraphically important foraminifera species of Gavelinella, Stensioeina, Protostensioeina, Bolivina, Bolivinoides, Pyramidina, Pseudouvigerina and planktonic foraminifera (Contusotruncana, Globotruncana, Marginotruncana), and 40 ostracod taxa are presented. A list of taxa with taxonomic notes and descriptions of five new foraminifera species, Gavelinella praestelligera, G. praethalmanni, G. praetumida, Protostensioeina ukrainica and Stensioeina praeexsculpta, and three informal species, Pyramidina sp. A, B and C is included. Evolutionary lineages of foraminifera genera provide the basis for a refined biostratigraphy that is successfully correlated to Salzgitter-Salder, Germany and Dubivtsi, Ukraine. Records are compared to literature data and benthic foraminifera zonations across northern Europe. However, differing taxonomic concepts of authors hamper comparison with literature data, exemplified by critical review of previous work at Seaford Head. This precludes rigorous assessment of diachronism of marker species, although regional stratigraphic differences in the distribution of the first stensioeinids and representatives of the Gavelinella clementiana group in Europe are apparent. The first detailed ostracod records from the English Coniacian – Campanian are presented. Four new ostracod biozones defined by the lowest occurrences of the index taxa are proposed: Neocythere (Physocythere) virginea; Limburgina senonensis; Phacorhabdotus lonsdaleianus; and Pterygocythere laticristata zones.

描述了英国南部Seaford Head的上Turonian -下Campanian白垩系序列，并确定了阶段和次阶段边界的位置。本文对该段有孔虫类和介形虫类的研究进行了综述。提供了99个样本的新数据，覆盖了整个暴露剖面。样品产生了大量保存完好的各种微化石组合。本文介绍了38种具有重要地层意义的有孔虫（Gavelinella, Stensioeina, Protostensioeina, Bolivina, Bolivinoides, Pyramidina, Pseudouvigerina）和浮游有孔虫（Contusotruncana, Globotruncana, Marginotruncana）以及40个介形虫类群的地层分布。本文收录了有孔虫新种（Gavelinella praestelligera、g.p aeethalmanni、g.p praetumida、Protostensioeina ukrainica和praeexsculpta）和非正式种（Pyramidina sp. A、B和C），并附有分类注释和描述。有孔虫属的进化谱系为精细的生物地层学提供了基础，成功地将其与德国萨尔茨吉特-萨尔德和乌克兰杜比夫茨相关联。将记录与文献数据和北欧底栖有孔虫带进行比较。然而，作者的不同分类概念阻碍了与文献数据的比较，例如对以前在西福德海德工作的批判性审查。这就排除了对标志物种的历时性的严格评估，尽管在欧洲，第一批张氏纲和Gavelinella clementana群的代表在分布上的区域地层差异是明显的。本文首次详细记录了英国康涅西亚-坎帕尼亚的介形类。本文提出了四个新的介形类生物带：Neocythere (physicythere) virginea；Limburgina senonensis;Phacorhabdotus lonsdaleianus;和翼状细胞的乳化带。

{"title":"Foraminifera and ostracod biostratigraphy of the English Coniacian – Campanian (Upper Cretaceous) Chalk: New results from Seaford Head and correlation to Eastern Europe","authors":"Ian Jarvis , Zofia Dubicka , Markéta Chroustová","doi":"10.1016/j.cretres.2025.106215","DOIUrl":"10.1016/j.cretres.2025.106215","url":null,"abstract":"<div><div>The uppermost Turonian – lower Campanian Chalk succession at Seaford Head, southern England, is described and the placement of stage and substage boundaries are defined. Previous studies of foraminifera and ostracods in the section are reviewed. New data are provided for 99 samples spanning the full exposed section. Samples yielded abundant well-preserved diverse microfossil assemblages. The stratigraphic distributions of 38 selected stratigraphically important foraminifera species of <em>Gavelinella</em>, <em>Stensioeina</em>, <em>Protostensioeina</em>, <em>Bolivina</em>, <em>Bolivinoides</em>, <em>Pyramidina</em>, <em>Pseudouvigerina</em> and planktonic foraminifera (<em>Contusotruncana, Globotruncana, Marginotruncana</em>), and 40 ostracod taxa are presented. A list of taxa with taxonomic notes and descriptions of five new foraminifera species, <em>Gavelinella praestelligera, G. praethalmanni, G. praetumida, Protostensioeina ukrainica</em> and <em>Stensioeina praeexsculpta</em>, and three informal species, <em>Pyramidina</em> sp. A, B and C is included. Evolutionary lineages of foraminifera genera provide the basis for a refined biostratigraphy that is successfully correlated to Salzgitter-Salder, Germany and Dubivtsi, Ukraine. Records are compared to literature data and benthic foraminifera zonations across northern Europe. However, differing taxonomic concepts of authors hamper comparison with literature data, exemplified by critical review of previous work at Seaford Head. This precludes rigorous assessment of diachronism of marker species, although regional stratigraphic differences in the distribution of the first stensioeinids and representatives of the <em>Gavelinella clementiana</em> group in Europe are apparent. The first detailed ostracod records from the English Coniacian – Campanian are presented. Four new ostracod biozones defined by the lowest occurrences of the index taxa are proposed: <em>Neocythere (Physocythere) virginea</em>; <em>Limburgina senonensis</em>; <em>Phacorhabdotus lonsdaleianus</em>; and <em>Pterygocythere laticristata</em> zones.</div></div>","PeriodicalId":55207,"journal":{"name":"Cretaceous Research","volume":"178 ","pages":"Article 106215"},"PeriodicalIF":1.7,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145121162","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

More diverse and abundant than assumed: Eucommiidites pollen preserved in a deltaic setting (Lower Cretaceous) of the Araripe Basin (NE Brazil) 比想象的更加多样化和丰富：在Araripe盆地（巴西东北部）的一个三角洲环境（下白垩纪）中保存的真丝虫花粉

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2025-08-30 DOI: 10.1016/j.cretres.2025.106210

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

Twelve species of Eucommiidites pollen from deltaic sedimentary rocks of the Rio da Batateira and lowermost Crato formations are here described and depicted with light microscopy (LM) and scanning electron microscopy (SEM). A clump of Eucommiidites sp. 6 from sample CAS 27 of the lowermost Crato Formation is thought to be the dispersed equivalent of in situ pollen of Araripestrobus resiniferous found in the laminitic limestone of the Crato Formation. The other Eucommiidites taxa are known only as dispersed taxa. The separation of individual Eucommiidites species using LM is often very difficult and helped by the use of SEM to observe the position of lateral sulci/furrows, plus the sculpture and ornamentation of the sulcus membrane and ektexine. Only two Eucommiidites taxa, E. sp. 2 and E. sp. 3, occur frequently and generally abundantly in medium percentages (4–15 %) in the pollen sum throughout the section, and are interpreted to come from either wind pollinated plants or plants with no specific edaphic requirements. All other taxa are interpreted to have grown further away from the distributary channels, probably in more specialized stands. Two of them (Eucommiidites sp. 6 and E. sp. 8) are preserved in clumps and are suggested to be animal pollinated. The presence of unusually high percentages of 8–14 % of Eucommiidites in the pollen sums reveal that Eucommiidites taxa constituted a significant portion of the ancient vegetation habitats located upriver, but only comprise a few fragments in the macrofossil record of the Araripe Basin.

本文用光学显微镜（LM）和扫描电镜（SEM）对巴泰拉盆地里约热内卢da Batateira和克拉托盆地最下层的三角洲沉积岩中的12种真丝虫花粉进行了描述和描绘。在克拉托组下部CAS 27样品中发现的一团eucommiites sp. 6被认为是在克拉托组层状灰岩中发现的Araripestrobus resiniferous原位花粉的分散等效物。其他真丝目分类群只被称为分散分类群。借助扫描电镜观察侧面沟/沟的位置，再加上沟膜和边缘的雕刻和纹饰，利用LM分离单个的真丝虫物种通常是非常困难的。在整个剖面的花粉总数中，只有2个菊科植物分类群E. sp. 2和E. sp. 3以中等比例（4 - 15%）出现频率高且数量普遍丰富，可以解释为来自风传粉植物或无特定土壤要求的植物。所有其他分类群都被解释为生长在离分流河道更远的地方，可能是在更专门的林分上。其中2种（eucommidites sp. 6和e.p sp. 8）呈丛状保存，推测为动物传粉。在花粉总数中，真丝虫的比例高达8 ~ 14%，表明真丝虫类群在上游古植被生境中占有重要地位，但在Araripe盆地的宏观化石记录中仅占少数碎片。

{"title":"More diverse and abundant than assumed: Eucommiidites pollen preserved in a deltaic setting (Lower Cretaceous) of the Araripe Basin (NE Brazil)","authors":"Christa-Ch. Hofmann , Ulrich Heimhofer , Emily A. Roberts , Leyla J. Seyfullah","doi":"10.1016/j.cretres.2025.106210","DOIUrl":"10.1016/j.cretres.2025.106210","url":null,"abstract":"<div><div>Twelve species of <em>Eucommiidites</em> pollen from deltaic sedimentary rocks of the Rio da Batateira and lowermost Crato formations are here described and depicted with light microscopy (LM) and scanning electron microscopy (SEM). A clump of <em>Eucommiidites</em> sp. 6 from sample CAS 27 of the lowermost Crato Formation is thought to be the dispersed equivalent of <em>in situ</em> pollen of <em>Araripestrobus resiniferous</em> found in the laminitic limestone of the Crato Formation. The other <em>Eucommiidites</em> taxa are known only as dispersed taxa. The separation of individual <em>Eucommiidites</em> species using LM is often very difficult and helped by the use of SEM to observe the position of lateral sulci/furrows, plus the sculpture and ornamentation of the sulcus membrane and ektexine. Only two <em>Eucommi</em><em>i</em><em>di</em><em>tes</em> taxa<em>, E</em>. sp. 2 and <em>E</em>. sp. 3, occur frequently and generally abundantly in medium percentages (4–15 %) in the pollen sum throughout the section, and are interpreted to come from either wind pollinated plants or plants with no specific edaphic requirements. All other taxa are interpreted to have grown further away from the distributary channels, probably in more specialized stands. Two of them (<em>Eucommiidites</em> sp. 6 and <em>E</em>. sp. 8) are preserved in clumps and are suggested to be animal pollinated. The presence of unusually high percentages of 8–14 % of <em>Eucommiidites</em> in the pollen sums reveal that <em>Eucommiidites</em> taxa constituted a significant portion of the ancient vegetation habitats located upriver, but only comprise a few fragments in the macrofossil record of the Araripe Basin.</div></div>","PeriodicalId":55207,"journal":{"name":"Cretaceous Research","volume":"179 ","pages":"Article 106210"},"PeriodicalIF":1.7,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145520350","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