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71.
Góis, F., Scillato-Yané, G.J., Carlini, A.A. & Guilherme, E. 2013. A new species of Scirrotherium Edmund & Theodor, 1997 (Xenarthra, Cingulata, Pampatheriidae) from the late Miocene of South America. Alcheringa 37, 175–186. ISSN 0311-5518.

A new species of Scirrotherium Edmund & Theodor (Pampatheriidae) is described: S. carinatum. This genus was previously represented by a single species, S. hondaensis Edmund & Theodor, 1997, recorded from the middle Miocene (Laventan) of Colombia. Pampathere remains are common in the ‘Conglomerado osífero’ (late Miocene) of the Ituzaingó Formation in the Paraná River cliffs of Entre Ríos, Chubut (Argentina) and Acre (Brazil). All of them were referred to Kraglievichia paranense, and they are mostly osteoderms. However, only a few of these specimens are strictly consistent with that species. The new species described herein differs from S. hondaensis in having very thin osteoderms with more elaborate ornamentation. The movable band (or imbricate) osteoderms have a sculptured exposed surface and a single transverse row of anterior foramina; the lateral margins are wider and also bear foramina, and the longitudinal central elevation is long and proximally wide, and forms a posteriorly raised crest. This elevation is delimited by a fairly broad and shallow depression on each side, separating the marginal elevation from the longitudinal central one. The exposed surfaces of fixed (or fused) osteoderms bear large and deep anterior foramina, the longitudinal central elevation and delimiting depressions are very pronounced. This new species increases the known diversity of the pampatheres from the ‘Conglomerado osífero’. Additionally, a new nomenclatural scheme for Pampatheriidae osteoderms is proposed.

Flávio Góis [goisf@fcnym]unlp.edu.ar], Gustavo Juan Scillato-Yané [scillato@fcnym.unlp.edu.ar], Alfredo Armando Carlini [acarlini@fcnym.unlp.edu.ar], Departamento Científico Paleontología Vertebrados, Museo de La Plata, Paseo del Bosque, s/n, 1900, La Plata, Buenos Aires, Argentina and CONICET; Edson Guilherme [guilherme@ufac.br], Universidade Federal do Acre, Laboratório de Pesquisas Paleontológicas (LPP), BR 364, Km 04, 69.915-900. Rio Branco, AC, Brazil. Received 11.5.2012; revised 31.7.2012; accepted 4.9.2012 .  相似文献   
72.
73.
An oil‐bearing sandstone unit within the Monterey Formation is exposed in the Los Angeles Basin along the Newport‐Inglewood fault zone in southern California. The unit preserves structures, some original fluids, and cements that record the local history of deformation, fluid flow, and cementation. The structures include two types of deformation bands, which are cut by later bitumen veins and sandstone dikes. The bands formed by dilation and by shear. Both types strike on average parallel to the Newport‐Inglewood fault zone (317°–332°) and show variable dip angles and directions. Generally the older deformation bands are shallow, and the younger bands are steep. The earlier set includes a type of deformation band not previously described in other field examples. These are thin, planar zones of oil 1–2 mm thick sandwiched between parallel, carbonate‐cemented, positively weathering ribs. All other deformation bands appear to be oil‐free. The undeformed sandstone matrix also contains some hydrocarbons. The oil‐cored bands formed largely in opening mode, similar to dilation bands. The oil‐cored bands differ from previously described dilation bands in the degree of carbonate cementation (up to 36% by volume) and in that some exhibit evidence for plane‐parallel shear during formation. Given the mostly oil‐free bands and oil‐rich matrix, deformation bands must have formed largely before the bulk of petroleum migration and acted as semi‐permeable baffles. Oil‐cored bands provide field evidence for early migration of oil into a potential reservoir rock. We infer a hydrofracture mechanism, probably from petroleum leaking out of a stratigraphically lower overpressured reservoir. The deformation bands described here provide a potential field example of a mechanism inferred for petroleum migration in modern systems such as in the Gulf of Mexico.  相似文献   
74.
张夏组碳酸盐岩是龙门石窟主要造窟地层,水岩作用强烈。近年来酸雨进一步加剧了龙门石窟碳酸盐岩的溶蚀。为了对龙门石窟的保护提供相关资料,需进一步探讨鲕粒灰岩的抗风化能力。为此,对东山石窟区所在张夏组分层、取样,进行成分、微观结构分析,并通过室内酸雨溶蚀模拟实验来研究张夏组地层的溶蚀规律。研究表明,龙门石窟张夏组各地层溶蚀差异较大,其单位面积溶蚀质量与钙镁比正相关;鲕粒灰岩风化后表面粗糙度与鲕粒含量密切相关;研究区张夏组鲕粒成分主要为白云石,鲕粒灰岩的抗化学侵蚀能力比普通灰岩更强。通过对张夏组地层岩性的分析及其溶蚀规律的研究,为龙门石窟的保护提供了基础科学资料。  相似文献   
75.
SHIH, M.J.H., LI, L.F. & REN, D., April 2017. Application of geometric morphometric analyses to confirm two new species of Karatavitidae (Hymenoptera:Karatavitoidea) from northeastern China. Alcheringa 41, 499–508. ISSN 0311-5518

Two new species, Praeratavites rasnitsyni and Karatavites ningchengensis in the wasp family Karatavitidae, are described and illustrated. These specimens were collected from the uppermost Middle Jurassic Jiulongshan Formation at Daohugou Village in Inner Mongolia, China. Key venation characters, as measured by relative positions or length ratios, are summarized for all documented species of Karatavites and Praeratavites to facilitate morphological comparisons and assess whether the studied specimens are referable to new species. In addition, geometric morphometric analyses were conducted to confirm the distinction of the new species, which add to the diversity of these genera in the Middle Jurassic.

Matthew J.H. Shih* [] Union County Magnet High School, Scotch Plains, NJ 07076, USA; Longfeng Li [] and Dong Ren [] College of Life Sciences, Capital Normal University, 105 Xisanhuanbeilu, Haidian District, Beijing 100048, PR China. *Also affiliated with: Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA.  相似文献   

76.
论撒拉族商业文化——概念、形成环境及功能   总被引:1,自引:0,他引:1  
撒拉族是我国少数民族中一个独特的民族,在我国10个信仰伊斯兰教的民族中,撒拉族的商业发展令人瞩目,根本原因在于商业实践背后的商业文化在起着巨大作用。什么是撒拉族商业文化,它形成的环境是什么,又具有什么样的功能,将一一揭开这些问题的答案。  相似文献   
77.
Eighteen genera of cosmopolitan marine algae are reported from Emsian and Eifelian limestones of New South Wales. Couvinianella, Paralitanaia, Perrierella, Pseudopalaeoporella and Renalcis are the most abundant taxa. Three distinctive floras are recognized: a prolific dasycladale-coccoid assemblage; a diverse udoteacean assemblage; and an undiversified udoteacean assemblage. None of these floras has a precise stratigraphic significance, although they indicate a latest Silurian-Middle Devonian age. Maslovina australense sp. nov. is described.  相似文献   
78.
本文通过网络访谈和案例搜集数据资料,采用扎根理论范式的质性分析方法,借助Nviv08.0软件对原始资料进行信息整理、数据编码,最后归纳提取4个核心范畴,即影响“驴友”旅游安全的4个维度影响因素类属:个人因素、机械(设备)因素、环境因素、管理因素。进而以“驴友”旅游的整个过程为主线,结合各阶段的事故诱发因子,深入剖析了“驴友”在旅游准备阶段、旅游体验阶段、事故发生及救援阶段的安全事故的形成机理;同时,基于“驴友”的安全认知和安全意识,以及“驴友”旅游过程中的安全行为,将“驴友”细分成谨慎型、大众平衡型、冒险型三种类型。  相似文献   
79.
An isolated ischium and possible neural arch recovered from the lower–middle Albian Griman Creek Formation near Surat, are the only sauropod postcranial elements from that unit in Queensland. This is the southernmost occurrence of sauropod post-cranial remains in eastern Australia. Comparison with other sauropod remains suggests that the ischium might represent an indeterminate titanosaur that is different from taxa previously named from Australia.  相似文献   
80.
The Dansirit Formation of the Shemshak Group is well exposed in the Parvar area, near the Rudbarak village, Central Alborz, Iran. It contains abundant well-preserved plant macrofossils belonging to 20 taxa of Equisetales, Marattiales, Filicales, Bennettitales, Cycadales, Corystospermales, Caytoniales, Czekanowskiales, Ginkgoales and Pinales. The new species Caytonia iranica sp. nov. is described. Based on the occurrence of Equisetites beanii, Coniopteris hymenophylloides, Nilssonia sarakhs, Czekanowskia blacki and Pseudoctenis fragilis, an early Middle Jurassic age is suggested for this assemblage.  相似文献   
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