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破城子冰期是天山地区第四纪冰期划分中最具代表性的冰期之一,其沉积地形为形态较清晰的多列终碛垅组成,呈扇形展布在最大的现代冰川作用中心托木尔峰东南坡的木扎尔特河河口与山麓带．冰碛地形记录了复杂的冰川进退史,包含着丰富的古环境变化信息,对它们进行研究有助于恢复这次冰期的冰川演化史与重建该地区的古环境．应用ESR测年技术,选用石英颗粒中对光照与研磨作用都较敏感的Ge心作为测年信号,对该处出露完整的沉积剖面Ⅰ层的冰川沉积、数列终碛垅与冰水沉积进行定年,获得3组年代分别为13．6～25．3,39．5～40.4与64．2～71．7ka．结合地貌地层学原理与其它研究资料进行综合分析可得出：破城子多列终碛垅形成于末次冰期,在末次冰川作用过程中该处存在至少3次大的冰进,可分别对应于MIS2,MIS3b与MIS4．MIS2与MIS3b时的冰川为复合山谷冰川,MIS4时的冰川为山麓冰川．三次冰进规模最大时的冰川长度分别约为94,95与99km． 相似文献
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大汶口盆地蕴藏着丰富的岩盐资源，岩盐矿矿层埋深较深，上覆地层为古近系巨厚的松散泥岩、砂岩,易发生遇水软化，施工难度较大。山东肥城海晶盐化有限公司实施100万t/年卤折盐采输卤工程，实施卤井7组，每组井深约3000 m。定向对接井要求精准定点造斜、连续造斜。本文介绍了对接井施工中采用的关键施工工艺及MWD无线随钻测斜仪在定向钻进中进行钻井轨迹控制的应用实例。对如何在岩盐地层钻进、螺杆钻具应用、定点造斜等关键技术措施进行了详细阐述，以期为同类型卤水对接井项目施工中提供参考。 相似文献
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The accumulation and ablation of a glacier directly reflect its mass income and wastage, and ice temperature indicates glacier＇s climatic and dynamic conditions. Glaciological studies at Baishui Glacier No.1 in Mt. Yulong are important for estimating recent changes of the cryosphere in Hengduan Mountains. Increased glacier ablation and higher ice temperatures can cause the incidents of icefall. Therefore, it is important to conduct the study of glacier mass balance and ice temperature, but there are few studies in relation to glacier＇s mass balance and active-layer temperature in China＇s monsoonal temperate glacier region. Based on the field observations of mass balance and glacier temperature at Baishui Glacier No.1, its accumulation, ablation, net balance and near-surface ice temperature structure were analyzed and studied in this paper. Results showed that the accumulation period was ranged from October to the following mid-May, and the ablation period occurred from mid-May to October, suggesting that the ablation period of temperate glacier began about 15 days earlier than that of continental glaciers, while the accumulation period began about 15 days later. The glacier ablation rate was 6.47 cm d 1 at an elevation of 4600 m between June 23 and August 30, and it was 7.4 cm d 1 at 4800 m between June 26 and July 11 in 1982, moreover, they respectively increased to 9.2 cm d 1 and 10.8 cm d 1 in the corresponding period and altitude in 2009, indicating that glacier ablation has greatly intensified in the past years. The temperature of the main glacier body was close to melting point in summer, and it dropped from the glacier surface and reached a minimum value at a depth of 4-6 m in the ablation zone. The temperature then rose to around melting point with the depth increment. In winter, the ice temperature rose gradually with the increasing depth, and close to melting point at the depth of 10 m. Compared with the data from 1982, the glacier temperature has risen in the ablation zone in recent decades. 相似文献
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对广东省南部花岗岩广泛发育地区的两个花岗岩风化剖面进行部分主量元素和重金属元素含量变化的研究表明:研究区成土过程是Na、Mg、K、Ca持续风化淋失的过程,且风化程度较高,土壤剖面中重金属元素与主量元素含量的变化趋势一致.研究区两土壤剖面的淋溶作用较强,淋溶层深达200 cm,淀积层深度为100～300 cm.在淀积层内,随着Ca、K、Na、Mg等主量元素的新生矿物沉淀,As、Cd、Pb、Zn、Ni等元素也相对富集,是广东地区深层土壤As、Pb等元素含量高于表层土壤的可能成因之一. 相似文献
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玉龙雪山周边典型河流雨季水化学特征分析 总被引：7，自引：0，他引：7
2009 年5~10 月在玉龙雪山周边典型小流域白水河、三束河、哥吉河采集河水样品,水化学分析结果表明,三条河流河水均呈现弱碱性,主要离子组成表现为富集Ca2++Mg2+和HCO3-+SO42-,且以Ca2+和HCO3-为主,各类离子存在显著季节变化。离子来源分析表明,玉龙雪山周边小流域河水雨季主要受降水和岩石风化影响,大气降水对河水主要常规离子Na+、K+、Ca2+、Mg2+、SO42-的贡献率为分别为23.44%,9.66%,3.10%,17.81%,10.48%。研究区碳酸盐岩的风化产物是河水离子组成的主要控制因素。 相似文献
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本文报导了以海捕日本对虾进行人工越冬,然后切除雌虾单侧眼柄,投喂优质饵料,控制适当的生态条件,通过精心的管理,促进日本对虾性腺成熟并培育出虾苗的试验过程。日本对虾越冬成活率为93.3％,性腺促熟率为86.6％,交配率为75.9％。眼柄切除后12天即进入产卵高峰,出苗量为9.6万尾/m~3,无节幼体到仔虾成活率为69.0％,育出日本对虾苗量145.5万尾。 相似文献
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Based on the meteorological and hydrologic data in the Lijang(丽江) basin from 1979 to 2006,variational trend and characteristics of climate change and its effect on runoff in Yanggong(漾弓) River were examined in the study.The results show that the temperature have significantly increased in the drainage basin during the past 28 years.The average temperature increased markedly from 1979 to 2006,and the increase of temperature in winter was higher than those in other seasons.The annual precipitation varied with... 相似文献
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采用玉龙雪山白水1号冰川2011年6～9月的高精度GPS实测数据,对白水1号冰川的运动速度进行了探索性研究,并与其他数条典型冰川作了对比分析。结果表明,与北半球典型大陆性冰川相比,玉龙雪山白水1号冰川运动速度明显偏快,介于2.34～4.74 m/月之间,是同规模大陆性冰川的月运动速度的6～10倍,有独特的海洋性冰川运动特征。与藏东南同一类型的帕隆94冰川相比,玉龙雪山白水1号冰川运动速度约为其一半,这说明海洋性冰川的运动速度与规模成正比。同时,白水1号冰川末端平均海拔为4 381 m,近10年几乎保持了相同的退缩速度,说明在当今气候变化背景下,白水1号冰川对气候变暖的响应程度相同。 相似文献
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改革开放以来，我国与世界的交往越来越多，政策的实施与深人发展，也使我国全方位与世界许多国家发生着政治、经济、文化等多方面、多层次的联系。洞开的国门也吸引着外国投资者，旅游者，社会对外语人才，尤其是英语专业人才的需求越来越大。在社会需求逐渐增加，而外语人才，尤其是英语专门人才相对匮乏的情况下，我国教育主管部门积极鼓励扩大英语专业建设，在已有的外语院校以及国内重点综合大学英语系加快发展的情况下，鼓励许多具备条件的理工类院校也开设英语专业。创办初期，我国理工院校的英语专业同国内重点外语院校以及重点大学或师范院校的英语系大体上是同一种发展模式：都注重英语基本功的训练，注重人文知识的传授与培养。 相似文献