温度场和渗流场耦合对恐龙化石风化破坏的影响

在恐龙化石经受风化破坏过程中,温度和水是起作用的两大主要因素。为了深入探讨恐龙化石风化破坏机理,有效、科学、合理地保护恐龙化石,该文将恐龙化石及围岩作为岩体,运用岩体水力学研究中温度场与渗流场之间的耦合关系,研究温度和水在恐龙化石风化破坏过程中的内在机制。通过建立温度场与渗流场数值模型,模拟温度场与渗流场在恐龙化石风化过程中的相互作用,定性分析了温度与水相互作用对化石风化的破坏机理。     

叠后地震数据采集足迹消除技术Gabor算法的研究及应用

渤海矿区曹妃甸A构造位于渤海湾盆地、渤中凹陷与沙垒田凸起的连接处,是渤海湾盆地重要勘探区块之一。工区内三维地震资料采集时间较早,存在较强的采集足迹,尤其在目的层明化镇组下段,采集足迹与断层相互切割,严重影响断裂系统解释及构造认识,为油田下一步勘探、生产工作带来了很大困难。Gabor滤波技术选取不同方位进行特定频率滤波,有效滤除了采集足迹对地震资料的影响,解决了由于采集足迹影响导致的地震数据成像差的问题。通过该方法滤波后的地震资料断裂系统展布清晰,能够满足地质人员对油田工区构造情况进行分析,满足地质人员的要求,为后续油田勘探开发工作奠定了坚实可靠的基础,同时该方法的提出为其他油田相似情况提供了一定的参考。     

陕西安塞首次发现中侏罗世晚期恐龙足迹

在安塞地区野外地质考察过程中, 在直罗组顶部的一套砂岩地层中发现4枚恐龙足迹, 其中3枚为三趾型恐龙足迹; 另外还观察到3枚疑似恐龙足迹。根据足迹形态对比和足迹特征研究, 推断P3观察点三趾型恐龙足迹造迹者为大型肉食性兽脚类恐龙, 其他足迹的造迹者难以确认。该发现不仅扩大了鄂尔多斯盆地中侏罗世恐龙足迹的分布范围, 也为研究直罗组晚期的古环境提供了素材。     

西峡盆地含恐龙蛋化石剖面磁性地层学结果及其构造地质意义

通过对河南南阳西峡盆地含恐龙蛋化石的阳域—丹水剖面的岩石磁学与古地磁学研究表明,该陆相沉积地层的特征剩磁载体以赤铁矿与磁铁矿为主,特征剩磁通过了倒转检验,表明其很可能为岩石形成时期获得的原生剩磁.结合该剖面古生物资料,磁性地层学结果表明,剖面上部2973~3023 m处年代为83~79 Ma;该剖面蛋化石所在最高层位年龄不晚于83 Ma,暗示该地区大型爬行动物的绝灭可能与西峡地区当时的气候、环境变化有关.此外,自晚白垩世以来,该剖面所处位置相对华北和华南地块发生了约18°的顺时针旋转,可能由该地区的局部构造活动引起.     

河南淅川盆地上白垩统恐龙蛋一新蛋种

河南淅川盆地的恐龙蛋发现与研究始于1974年,淅川盆地恐龙蛋具有非常高的多样性,共计发现4个蛋科、6个蛋属、6个蛋种,尤其以树枝蛋类最为丰富。近年来,河南地质博物馆对全省地质遗迹调查过程中,在淅川盆地再次有新的恐龙蛋类型的发现,本文对其中的部分标本进行记述,根据壳单元呈多分叉的不规则树枝状,蛋壳厚度为1.62～1.74 mm,锥体间隙明显,壳单元自锥体上部开始出现分枝,蛋壳中部大多具有3～4个分枝,近蛋壳外表面形成融合层,蛋壳具有复杂的气孔系统等特征区别于其他类型的树枝蛋类,建立一新蛋种:大石桥树枝蛋(Dendroolithus dashiqiaoensis oosp. nov.)。通过对淅川盆地恐龙蛋分类与对比、不同类型恐龙蛋在地层中的分布研究,将有助于盆地内白垩纪红层的划分,也将为秦岭东段各盆地中同一时期红层的划分与对比、古地理、古环境和古气候等研究提供更加翔实的古生物学证据。     

On the devil's tracks: unexpected news from the Foresta ichnosite (Roccamonfina volcano,central Italy)

The Foresta ichnosite is well known for preserving some of the oldest human fossil footprints recorded in Europe so far. This research aims to: i) describe new footprints that are larger than those already reported, some of which form a new trackway that moves in the opposite direction to all the others; ii) announce the discovery of some stone tools also in the surroundings of the Foresta ichnosite. The new results increase the total number of human fossil footprints to at least 81, specify the direction and the number of footprints of Trackway C, and identify three new directions of walking at the site. More compelling and complete estimates of the dimensional range of all ichnological evidence enables us, furthermore, to estimate the number of trackmakers walking on the trampled surface as a minimum of five, one of them likely being an adult male. The general shape of all the recorded footprints suggests that the Foresta trackmakers share some similarities with those at Sima de los Huesos, and belong to the same taxonomical group as the Ceprano skull. All the new evidence enables us to better understand the presence of hominin populations in the Roccamonfina volcano area during the Middle Pleistocene. © 2020 John Wiley & Sons, Ltd.     

山东诸城地区早白垩世一新龟类足迹

1923年Nopcsa命名的Emydichnium是龟类足迹最早的报道,后来其他一些中生代的足迹也被陆续报道描述。但是大多数化石只显示出或多或少的明显爪印或者划痕,无法反映造迹者足部较为全面的生物学特征。山东诸城皇龙沟足迹点保存了早白垩世大量形态多样的龟类足迹,本文对其中一保存较好,能够反映足部生物学特征的龟类足迹进行了详细描述,并依据数据统计与莱阳足迹Liayangpus进行对比,显示两者存在明显不同。诸城的龟类足迹区别于以往发现的龟类足迹,因此根据其形态建立新种：完整诸城足迹Zhuchengichnites perfectus。本文亦对中国发现的龟类足迹化石点的层位、保存类型等进行了总结。     

Agricultural and forestry trade drives large share of tropical deforestation emissions

Deforestation, the second largest source of anthropogenic greenhouse gas emissions, is largely driven by expanding forestry and agriculture. However, despite agricultural expansion being increasingly driven by foreign demand, the links between deforestation and foreign demand for agricultural commodities have only been partially mapped. Here we present a pan-tropical quantification of carbon emissions from deforestation associated with the expansion of agriculture and forest plantations, and trace embodied emissions through global supply chains to consumers. We find that in the period 2010–2014, expansion of agriculture and tree plantations into forests across the tropics was associated with net emissions of approximately 2.6 gigatonnes carbon dioxide per year. Cattle and oilseed products account for over half of these emissions. Europe and China are major importers, and for many developed countries, deforestation emissions embodied in imports rival or exceed emissions from domestic agriculture. Depending on the trade model used, 29–39% of deforestation-related emissions were driven by international trade. This is substantially higher than the share of fossil carbon emissions embodied in trade, indicating that efforts to reduce greenhouse gas emissions from land-use change need to consider the role of international demand in driving deforestation. Additionally, we find that deforestation emissions are similar to, or larger than, other emissions in the carbon footprint of key forest-risk commodities. Similarly, deforestation emissions constitute a substantial share (˜15%) of the total carbon footprint of food consumption in EU countries. This highlights the need for consumption-based accounts to include emissions from deforestation, and for the implementation of policy measures that cross these international supply-chains if deforestation emissions are to be effectively reduced.     

The first lizard fossil (Reptilia: Squamata) from the Mesozoic of South Korea

Upper Cretaceous deposits in Mongolia, Chinese Inner Mongolia, and, more recently, southern China, have yielded individually rich and taxonomically diverser lizard assemblages. Here we describe the remains of a new terrestrial lizard, Asprosaurus bibongriensis gen. et sp. nov., from the Upper Cretaceous of South Korea. It represents the first record of a Mesozoic lizard from the Korean Peninsula and, although incomplete, is exceptional in its very large size. Characters of the mandible support attribution to crown-group Anguimorpha, with the closest similarities being to monstersaurs, the group represented today by the venomous North American Beaded lizard and Gila monster, genus Heloderma. This group is well-represented in the Upper Cretaceous fossil record in of eastern Asia, and the remains of large monstersaurs have been recovered from several dinosaur egg localities, suggesting dietary preferences similar to those of the living genus. The new Korean lizard, recovered from the Boseong Bibong-ri Dinosaur Egg Site, fits the same pattern.     

Current situation of the ichnological locality of São Domingos from the Corda Formation (Lower Cretaceous), northern Tocantins state,Brazil

In the 80's, Leonardi treated the presence of a vertebrate ichnological locality from the Barremian Corda Formation, Parnaíba Basin, on the left bank of the Tocantins river, near of the São Domingos town, Itaguatins, State of Tocantins, Brazil. Originally, the record was composed of at least seven in situ trackways, accounting for fifty six tracks. Since 2011, the Hydroelectric Power Plant do Estreito has begun to work, causing the development of a water reservoir 160 km upstream to the ichnological site, causing periodic and highly energetic floods over the footprints-bearing level and altering it. The imprints are poorly to moderate preserved, but it is possible to distinguish the general morphology and the spatial arrangement of the footprints. The specimens are represented by pes imprints, mostly circular to subcircular, with no digital and claw impressions. No distinguishable manus imprints are present. The trackways are relative narrow with respect to the size of the tracks, so they are considered into the Parabrontopodus-like category. The São Domingos tracks have been originally assigned to iguanodontid dinosaurs, and posteriorly related to a sauropodian origin. This idea is herein accepted, particularly to a basal sauropod, basal macronarians, or diplodocoids. Up to date, the tracks from the São Domingos locality are the only vertebrate fossil record from the Corda Formation, meaning an important contribution to the Cretaceous ichnofauna from South America.