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101.
Two new species, Cretohypna puncta sp. nov. and Cretohypna robusta sp. nov., of Glaphyridae are described and illustrated. These fossils were collected from the Jehol Biota, Lower Cretaceous Yixian Formation of Liutiaogou Village in Ningcheng, Inner Mongolia, China. Up to date, 18 fossil species in 6 genera of Glaphyridae have been reported, among which ten species are from China. Respective keys to the Mesozoic genera of Glaphyridae and to species of Cretohypna Yan, Nikolajev & Ren, 2012 are provided. This is the first report of spiracles in fossil Glaphyridae leading to a hypothesis that the character of the 7th abdominal spiracles present in pleural membrane is a plesiomorphy for Glaphyridae. 相似文献
102.
Specimens of the Venicoridae (Heteroptera) occur in the Lower Cretaceous Yixian Formation in northeastern China. We describe a new genus and two new species Halonatusivena shii gen. et sp. nov. and Halonatusivena nervosus sp. nov. from this formation. The veins of the membrane are distinctive; the edges of veins are not simple but resemble an irregular stain, with a reduced vasiform structure previously unknown in the Heteroptera. Remarkably, the antennae of one of the specimens of Halonatusivena shii exhibit morphological abnormality. An identification key for the known species of the Venicoridae is provided. 相似文献
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104.
内蒙古阿拉善右旗石窝子―三个井地区位于华北板块西北缘与塔里木板块东北缘的结合部位,北部紧邻西伯利亚板块(郝立波等, 2004)。三级成矿带属于朱拉扎嘎―甲生盘元古代、古生代金、铅、锌、硫、铁、铜、铂、镍成矿带(Ⅲ12),四级成矿带属于朱拉扎嘎金成矿带(Ⅳ123)(内蒙古自治区地质矿产局, 1991)。区域上已发现的矿种主要有煤、盐湖、芒硝、铁、金、磷、石灰岩、石膏、膨润土、滑石、饰面花岗岩等,代表性矿床有叠布斯格、卡休他他铁矿,朱拉扎嘎金矿,脑木洪铜多金属矿等。 相似文献
105.
107.
大红山地区是云南省重要矿集区之一,已发现大红山大型铁铜矿床及东么、底巴都、底戛母、河口、坝达等多个中小型铁铜矿床(点),区内分布多个磁异常及化探异常,成矿地质条件优越。近年云南省三年地质找矿行动计划项目“云南省新平县大红山外围铁、铜矿资源普查”经过勘查在大红山外围东么、底巴都矿区圈定多个工业铁、铜矿体及超贫磁铁矿体,取得一定找矿新进展。本文根据近年工作中观察到的新现象、取得的新资料,结合前人研究成果,对大红山地区铁、铜矿床成因类型及形成机理进行探讨。 相似文献
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109.
当前我国正处经济增速减缓的新常态,供给侧结构性改革应运而生。我国乃至世界的矿业更是处于发展的严冬之季,产能严重过剩,大宗商品价格持续走低。在当前形势下,我们要用新常态眼光看待矿业未来发展之路,因地制宜,着力加强供给侧改革,刻不容缓。 相似文献
110.
C. Klootwijk 《Australian Journal of Earth Sciences》2016,63(5):513-549
Structural, magnetic and gravity trends of the southern New England Orogen (SNEO) indicate four oroclinal structures, none conclusively confirmed paleomagnetically. Curved structures of the Tamworth Belt (TB)—a continental forearc exposed across six tectono-stratigraphic blocks with interlinked Carboniferous stratigraphies and extensive ignimbritic rocks known to retain primary magnetisations despite prevalent overprinting—are prospective to oroclinal testing through comparison of Carboniferous pole paths for individual blocks. Pole paths (a) have been established for the Rocky Creek and Werrie blocks (northwestern/western TB), (b) are described herein for the Rouchel Block (southwestern TB), and (c) are forthcoming for the Gresford and Myall blocks (southern/southeastern TB). The Rouchel path derives from detailed paleomagnetic, rock magnetic and magnetic fabric studies. Thermal, alternating field and liquid nitrogen demagnetisations show a low-temperature overprint, attributed to late Oligocene weathering, and high-temperature (HT) primary and overprint components in both magnetite and hematite carriers, showing slight, systematic, directional differences with hematite providing the better cleaned site poles. Seven primary mean-site poles of Tournaisian and mainly Visean age and three overprint poles show six positive fold tests, five at 95% or higher confidence levels. Two dispersed groupings of intermediate (IT) and HT overprint site poles of Permian and Permo-Triassic age are attributed to early and late phases in oroclinal evolution of the SNEO. HT and IT/HT overprint site poles of mid-Carboniferous age are attributed to Variscan Australia–Asia convergence. Individual pole paths for the Rocky Creek, Werrie and Rouchel blocks show no noticeable rotation between them, indicating primary curvature for the southwestern TB. Their integrated SNEO pole path establishes a reference frame for determining rotations of the southern and southeastern TB. 相似文献