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31.
LIU Yanxue LIU Yongqing ZHANG Hong 《《地质学报》英文版》2006,80(5):733-742
LA-ICPMS Zircon U-Pb dating is applied to volcanic rocks overlying and underlying the Salamander-bearing bed in the Daohugou beds of Ningcheng in Inner Mongola and Reshuichang of Lingyuan and Mazhangzi of Jianping in western Liaoning. The results indicate that the youngest age of the rocks in Daohugou of Ningcheng is 158 Ma, and the oldest one is 164 Ma. Synthesized researches indicate that the salamander-bearing beds in Daohugou of Ningcheng, Reshuichang of Lingyuan and Mazhangzi of Jianping were developed in the same period. The Daohugou beds were formed in the geological age of 164-158 Ma of the middle-late Jurassic. Whilst, the Daohugou beds and its corrdative strata should correspond to the Tiaojishan Formation (or Lanqi Formation) of the middle Jurassic in northern Hebei Province and western Liaoning Province, based on the disconformity between the Daohugou beds and its overlaying beds of the Tuchengzi Formation of Late Jurassic and the Jehol Beds of early Cretaceous, and the disconformity between the Daohugou Beds and its underlying Jiulongshan Formation, which is composed of conglomerate, sandstone, shale with coal and thin coal beds. 相似文献
32.
本文用CN算法研究了辽宁省两个地震重点监视防御区的中强震前的强震发生概率增长时间,结果表明预测效果较好,有震报准率为90%,TIP预测警戒占时空率为30%左右,R值评分为0.6左右。在TIP预测的基础上,进一步用SIP方法分析这两个区域的空间背景发震概率的不均匀分布。综合应用TIP方法和SIP方法,对辽宁省及邻近地区进行了试验性地震预报。 相似文献
33.
34.
本文探讨了K_2S_2O_8氧化离子色谱法测定有机氮的实验条件,考察了淋洗剂离子价态及淋洗剂总离子强度对低浓度NO_3~-与高浓度SO_4~2-分离的影响;测定了11种含氮有机化台物有机氮的回收率。本法测定地下水中有机氮的结果与经典蒸馏法结果较为一致,具有操作简便、快速、准确,效率高的特点。 相似文献
35.
辽宁金伯利岩中的碳硅石与金刚石密切共生,具有颜色鲜艳、硬度大、蚀象发育、富含基性元素等特征,可作为金刚石找矿的矿物学标志。它与人造碳化硅区别明显,在晶体结构上前者以α—SiCⅡ型为主,后者则以α—SiCⅠ型为主;前者富台基性元素Cr、Ni、Co、V、Ti等,后者富含Mg、Al;前者蚀象发育,后者则无蚀象。在半导体性能上,前者以空穴型为主,后者以屯予型为主。 相似文献
36.
西昆仑及邻区新生代差异隆升的热年代学证据 总被引:3,自引:0,他引:3
通过总结和分析有关热年代学的资料, 认为西昆仑及邻区的隆升存在明显的时空差异性.第一, 隆升历史表现出明显的阶段性: 晚渐新世到早中新世(25~16Ma) 的部分隆升阶段、中新世中后期的快速隆升阶段(14~8Ma) 和晚中新世以来的整体强烈隆升阶段(6Ma以来).第二, 隆升在空间上显示出明显的差异性: 塔什库尔干-公格尔山地区的隆升主要集中在9Ma以来, 红其拉甫-库地地区的隆升主要集中在25~16Ma, 康西瓦-普鲁地区的隆升则主要在9Ma以来(集中在9~2Ma) 和25~12Ma.东西方向上表现为东西两端靠近构造结(喜玛拉雅西构造结和西昆仑-阿尔金构造结合部位) 的地方较新(主要在9Ma以来), 中间较老(主要在9Ma以前); 南北方向上, 西昆北地体在20Ma左右发生快速隆升, 西昆南地体在9~5Ma发生快速隆升, 而甜水海地体在5~2Ma发生快速隆升, 由北向南总体上呈现出由老到新的空间差异性. 相似文献
37.
DUAN Ye ZHANG Lijun Institute of Palaeontology Shenyang Normal University Shenyang China 《东北亚地学研究》2009,12(2):87-93
The Jianchang Basin is one of the main localities of the precious fossils of Jehol Biota in western Liaoning. The fossil-bearing horizons are mainly in the Yixian- and Jiufotang formations. In the Weijialing- Yaolugou of southwest Jianchang Basin, many precious fossils have been found at Luojiagou Bed of the 2nd Member of the Yixian Formation and at Xidian Bed of the 1 st member of the Jiufotang Formation. The geologic setting, sedimentary environment and paleogeography of the precious fossil-bearing beds were also studied. 相似文献
38.
辽西早白垩世早期热河生物群沉积环境及古地理综合研究 总被引:8,自引:2,他引:6
辽西地区早白垩世早期义县组以产出精美的热河生物群而闻名于世,热河生物群研究的每一个重要进展都引起国内外科学家的极大关注。然而热河生物群产出的古地理环境和盆地沉积特征的研究由于受到后期构造破坏和风化作用的影响,难以开展详细的野外工作,研究程度较低。本次系统的野外沉积学工作表明,辽西地区义县组6个沉积层形成于被动大陆边缘向前陆盆地演化过程中的各个阶段,区域沉积环境属于冲积扇-辫状河-曲流河-湖泊沉积体系。从老公沟层到金刚山层经历了沉积环境的频繁变化,岩相类型和岩石组合频繁更替,碎屑供给充分,快速沉积的演化过程,最终完成了盆地充填。全部沉积环境可进一步分为河流和湖泊两大类。河流沉积相在义县组各沉积层的早期占据主体部分,每一盆地构造演化旋回的沉积阶段都是从洪积扇到河流相开始的,并受当时的地质、地理和气候条件的差异分别向淡水湖泊沉积和咸水湖沉积演化。在以河流沉积为主的盆地充填阶段主要由洪(冲)积扇组合、洪泛平原组合和湖岸平原-三角洲组合三种组合模式构成。湖泊沉积主要由静水深湖沉积模式和半咸水湖的(膏盐)碳酸盐沉积模式构成。 相似文献
39.
Precious Fossil-Bearing Beds of the Lower Cretaceous Jiufotang Formation in Western Liaoning Province, China 总被引:1,自引:1,他引:0
ZHANG Lijun YANG Yajun ZHANG Lidong GUO Shengzhe WANG Wuli ZHENG Shaolin 《《地质学报》英文版》2007,81(3):357-364
Based on the subdivision into three members of the Lower Cretaceous Jiufotang Formation in western Liaoning, this paper deals mainly with the division and correlation of precious fossil bird-and reptile-bearing beds of the formation in the Dachengzi, Chaoyang, Dapingfang-Meileyingzi and Fuxin-Yixian basins. Among them, the precious fossil-bearing beds in the Dachengzi Basin may be recognized as the Xidagou Bed of the second member and the Yangcaogoudonggou Bed of the third member; those in the Chaoyang Basin may be confirmed as the Shangheshou Bed of the second member and the Dongpochi Bed of the third member; those in the Dapingfang-Meileyingzi Basin are as the Lamagou Bed of the second member, the Huanghuagou Bed of the lower third member and the Yuanjiawa Bed of the upper third member; and those in the Fuxin-Yixian Basin are listed as the Tuanshanzi Bed of the second member and the Pijiagou Bed of the third member. Since these basins are distinctly separated and the bird and reptile fossils are mostly new genera and species, we have to use the associated fossil ostracod assemblages as index to correlate the Xidagou Bed with the Shangheshou Bed and the Lamagou Bed, and to correlate the Yuanjiawa Bed with the Yangcaogoudonggou Bed and the Pijiagou Bed. Primarily, we established the sequence of the precious fossil-bearing beds of the Jiufotang Formation in western Liaoning. They are represented by, in ascending order, the Xidagou Bed of the second member, the Huanghuagou Bed of the lower third member, and the Yuanjiawa Bed of the upper third member. Obviously, this work has significance for the study on the time-space distribution and radiation of birds and dinosaurs during the period of the middle Early Cretaceous. 相似文献
40.
460铀矿床是我国华北地台北缘一个有代表性的火山岩型铀矿床,该矿床研究对我国北方火山岩型铀矿找矿具有理论指导意义。本文从岩石化学、微量元素、稀土元素、铀钍演化、共生与伴生元素、稳定同位素、成矿温度及成矿年龄等方面研究了矿床的地球化学特征,并探讨矿床的成矿机理,建立矿床的成矿模式。 相似文献