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61.
延庆千家店盆地土城子组底部不整合接触蓟县系雾迷山组,不见顶,主要分为3个岩性段,一段以复成分砾岩、砂砾岩为主;二段以紫红色、黑色薄层泥页岩和泥质粉砂岩为主;三段以复成分砾岩、含砾粗砂岩为主。前人在该盆地二段地层中发现大量动植物化石,有双壳类、叶肢介、昆虫、木化石、恐龙足迹等,但一直没有介形类、孢粉及恐龙化石的相关报道。在化石层位发现疑似"恐龙骨骼"化石,丰富了该区化石种类。通过LA-ICP-MS测年,得出一段底部年龄为157.62±0.69Ma;二段中上部年龄为157.13±0.96Ma。分析认为,千家店盆地土城子组主体沉积时代为晚侏罗世早期,在前人研究的基础上,通过多样的古生物化石来探讨该盆地古气候背景及沉积环境。  相似文献   
62.
The Late Triassic Rhaetian stage is perhaps best known in south-west Britain for the bone beds of the Westbury Formation, but there are other fossil-rich horizons within this and the underlying Blue Anchor Formation. Samples from a borehole drilled at the Filton West Chord, and collected from exposures near Bristol Parkway railway station, have yielded significant fossil material from both of these formations. The assemblage recovered from the Blue Anchor Formation is similar to those from the lower Westbury Formation, yielding roughly equal proportions of chondrichthyans and osteichthyans. Assemblages recovered from the Westbury Formation are typical of those from the upper Westbury Formation, in being dominated by osteichthyans. The borehole samples have produced the first recorded evidence of crinoids in the British Triassic, and the first evidence of coleoid cephalopods, in the form of grasping hooklets, from the Rhaetian, and indeed the first from the British Triassic.  相似文献   
63.
《第四纪科学杂志》2017,32(5):653-660
Our knowledge of past animal populations, including the geographical ranges of extinct species, has largely been derived from morphological analyses of skeletal fossil remains. However, a major barrier to the identification of the remains of extinct megafaunal species in archaeological and palaeontological sites is the highly fragmented nature of the material, which often precludes confident taxonomic identifications based on morphology. Biomolecular techniques are able to go beyond these limitations and are increasingly being used to make such identifications. Protein analysis offers a promising alternative to DNA techniques because they can be much cheaper, more amenable to high‐throughput processing and work on much older specimens. Here we demonstrate the potential of collagen fingerprinting in an Australian context by extracting collagen from 50‐ka kangaroo fossils from two caves in Tasmania, and identify several species including the extinct short‐faced kangaroo Simosthenurus occidentalis . Importantly, of the five fossil bones sampled that had hitherto been ascribed morphology‐based identifications below the family level, three had been incorrectly identified during an initial assessment of photographs taken in the field. Our results highlight the utility of using protein‐based methods for making genus‐level identification of marsupial bone, especially those that may form a basis for broader arguments such as that of late‐surviving megafaunal species.
  相似文献   
64.
周燕  王铁夫  张延洁  郑培玺 《地球学报》2005,26(Z1):228-229
采用超声波清洗及离子交换分离等技术,对新疆青铜时代古人类骨骼中样品进行预处理及分离,该方法制备的同位素锶样品,保证了样品在前处理过程中不受处外界物质的污染,并提取纯度高的锶用于质谱测试。  相似文献   
65.
Pterosaur bones are for the first time reported from the Tremp Syncline(Spain) and the southern Pyrenees.They come from the Torrebilles-2 site(Isona,Lleida Province) in the upper Maastrichtian part of the Tremp Formation,which falls within the C29r magnetochron.Fragmentary long bones are referred to the Pterosauria based on their cortical thinness,micro-architecture,and histological features.They belong to very large to possibly giant individuals.The most complete specimen is possibly a partial right femur.The review of the Maastrichtian pterosaur record shows that only a few specimens can be referred to the C29r(which contains the K/Pg boundary).The identification of fragmentary remains could improve our knowledge about the abundance and distribution of these flying sauropsids just before the end-Cretaceous mass extinction.  相似文献   
66.
察吾呼文化是青铜时代晚期至早期铁器时代新疆天山中部地区一支非常重要的考古学文化类型,尽管发现和发掘的该文化遗存较多,但针对该文化人群的生业模式的研究尚待深入.本研究选取了位于天山南麓中部的和静县莫呼查汗墓地以及遗址出土的人和动物骨骼材料进行碳氮稳定同位素分析,以揭示距今约3000年前该区域居民的食谱构成和生业模式形态....  相似文献   
67.
山东滕州西公桥遗址人骨的稳定同位素分析   总被引:8,自引:3,他引:8       下载免费PDF全文
文章应用稳定同位素C和N分析的方法,研究了山东滕州大汶口文化时期西公桥遗址先民的食谱,试图揭示该遗址先民生活方式、社会经济结构的变化。总体而言,该遗址样品保存较差,骨中骨胶原的含量较低,以C/N摩尔比作为标准,仅有8个样品属于未污染样品,可用作食谱分析。对样品进行稳定同位素C和N分析,结果表明:该遗址先民均为稻、粟混食,但在肉食资源获取上有所不同。以C3为主的先民,具有较低的δ15N;而以C4类为主的先民,δ15N值较高。在该遗址的发展过程中,人们的食物结构发生了一定的变化。  相似文献   
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