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901.
在绳索取心钻探过程中,井底温度与压力的实时测量,有助于改进取心工艺,提高岩心采取率;同时岩心在井底的原位测量数据对于了解岩心的物理特性有着重要意义,这一点在海域天然气水合物勘探中尤为明显。本文主要介绍了一种内置于保压取样钻具中的温压采集器的结构及其工作原理。该采集器采用干电池供电,单次工作时间>72 h,能够采集与存储整个取样过程中岩心管内的温度与压力参数,与电脑端连接后就能得到全部数据。通过搭载海洋地质十号钻探船,该采集器完成了一个回次的海试试验,得到了整个绳索取心钻进过程的温度与压力数据。经过分析,收集到的数据与实际取心工艺过程相符,数据平稳可靠。 相似文献
902.
在东佛罗里达外大陆架大约40m的海底,发现一种被钻孔和包壳的晚更新世鲕粒灰岩。鲕粒的包壳主要由两种矿物组成,通常情况下,内是放射状排殊镁方解石,而外层则是同心环状排列的文石。多数鲕粒的核心是磨圆的隐晶质颗粒,但也有一部分英颗粒和各种骨粒组成。鲕粒由块状方解石胶结物不完全胶结,部分粒间孔由微晶充填。放射壳层由具亮的阴极发光性的镁方解石组成,含大约12mol%的MбCO3和1000ppm的锶。在放射壳层中,铁和锰含量的一般变化范围分别为500-1000ppm和100-250ppm。同习环状壳层由不具阴极发光的文石组成,含大约11500ppm的锶和小于0.5mol%的MбCO3.心环状壳层中铁的含量范围一般为150-400ppm,而锰通常小于100ppm的检测限。作为次要伴生颗粒的棘皮动物碎片山镁方解石组成,具亮的阴极发光性。一些鲕粒的核心和块状方解石胶结物的薄外缘具阴极发光。微晶基质和大片的块状方解石胶结物不具阴极发兴。在鲕粒中,未见显示重结晶作用的结构迹象。这些鲕粒灰岩经历了大气淡水成岩作用阶段,但鲕粒壳层却未受其影响。我们认为,镁方解石层普在缺氧的海水中遭受成岩蚀变,这是一个尚未被人们认识的过程。在该过程中,镁推动而锰加入,但没有明显的结构蚀变,也没有发生矿物的稳定化作用,因此,我们认为其阴极发光性可能是海底的成岩蚀变造成的。 相似文献
903.
K. Balakrishna S.S. Suvarna G. Srinikethan G. Mugeraya P.K. Krishnakumar 《中国地球化学学报》2006,25(B08):268-269
Detailed time-series studies on the major ion geochemistry of tropical peninsular Indian rivers are lacking. In this backdrop, a small stretch of the Godavari River, globally ranking 32nd in terms of total discharge, is chosen for sampling at its mouth. The objectives are: (1) to understand the natural and anthropogenic sources controlling the major ion chemistry of the Godavari River at Rajahmundry, (2) processes controlling the temporal variations in major ions over a period of two years, (3) comparison of total dissolved solid (TDS) fluxes and weathering rates at Godavari River with other major tropical rivers. A total of 47 surface samples were collected, bimonthly, at five stations in the Godavari at Rajahmundry spaced over a distance of 6 km for a period of two years. Water samples were collected in pre-cleaned PP bottles. Parameters like temperature, pH, conductivity, dissolved oxygen, alkalinity were measured on-site. Samples collected for analysis of major ions were processed within a few hours of collection by filtering through 0.45 mm pore size millipore filters. Filtered water samples for major ions were transported to the laboratory in cleaned 250 mL PP bottles. Sodium and K were measured on a Flame Photometer, Ca and Mg on a Flame Atomic Absorption Spectrophotometer, Cl, NO3, SO4 by Ion Chromatography and SiO2 on a spectrophotometer. Chemical weathering of rocks controls the major ion chemistry of the Godavari River at its mouth as indicated by the alkaline nature of the river and dominant presence of Ca, Mg and HCO3 ions. Ca/Mg and Na/Mg ratios point its source to a mixture of lithological assemblages of basalt, granite-granodiorite, 相似文献
904.
905.
Comprehensive Assessment of Seawater Quality Based on an Improved Attribute Recognition Model 总被引:2,自引:0,他引:2
ZHANG Libing ) ) CHENG Jilin ) JIN Juliang ) * and JIANG Xiaohong ) ) College of Civil Engineering Hefei University of Technology Hefei P.R.China ) College of Hydraulic Engineering Yangzhou University Yangzhou P.R.China 《中国海洋大学学报(英文版)》2006,5(4):300-304
1IntroductionAssessment of environment quality,which plays ani mportant role in environmental science and engineer-ing,has shiftedfromtraditional qualitative analysis toquantitative calculation.Inrecent years,quite a num-ber of methods have been brought o… 相似文献
906.
CENOZOIC VOLCANISM AND GEOTHERMAL RESOURCES IN NORTHEAST CHINA 总被引:2,自引:0,他引:2
WANG Xi-kui QIU Shan-wen SONG Chang-chun KULAKOV Aleksey TASHCHI Stepan MYASNIKOV Evgeny 《中国地理科学(英文版)》2001,11(2):150-154
1 INTRODUCTION Northeast China is located in the eastern marginal part of Eurasian plate. There are about 700 Cenozoic volcanoes and about 50 000km2 volcanic rocks in Northeast China. The Cenozoic volcanism is related to the Pacific plate subducting, back-arc spreading and corresponding marginal continental rifting. About 700 Cenozoic volcanoes in Northeast China are concentrated at some places, so Shuangliao, Keluo, Wudalianchi, Yitong, Shulan, Shangzhi, Longgang, Jingbo Lake, … 相似文献
907.
ZHENG Xiaodong ) * ZHAO Jianmin ) XIAO Shu ) WANG Rucai ) WANG Shidang ) ZHOU Weiwu ) ) The Key Laboratory of Mariculture Ministry of Education Ocean University of China Qingdao P..R.China ) Wendeng Fishery Technical Extension Station Weihai P..R.China 《中国海洋大学学报(英文版)》2004,3(1)
1 Introduction ThegoldencuttlefishSepiaesculenta,aneriticanddemersalspecies,livesinthedepthof 1 0 - 1 0 0meters,andsometimesinseabottomsand .Itiswidelydistrib utedfromcentralHonshutoVietnamandthePhilip pines .Thegoldencuttlefishisalsoanimportantobjectof… 相似文献
908.
lINTRODUCTIONAstotourismofdevelopingcountries,asPecialresearchfieldwasdividedfrompopuIartourismstudybysomewestemresearchers,manyspecialwordswereoftenusedsuchas"twosectors","enclaveconstrUction",j'developingscale","govemment'sin-terferenceandtheindustryroleoftourism"(MARTIN,l993;JENKIN,l982;JENKINetal.,l982,E-MANUL,l992)'AspecialattentiongiventoChinaisonlysomepoliticalanalyzingabouttourism(RICHTER,1983;HALL,l994;TREVoR,l998).AstoChineseleisurelife,recentlysomepapershadbeen… 相似文献
909.
CHEN Junren WAN Ling Guangzhou Marine Geological Survey MGMR P. O. Box Guangzhou 《《地质学报》英文版》1999,73(2):216-224
Experimental examinations and analyses have been made of the sediments from drill holes in the Zhuhai area, Guangdong Province. The studies show that there occurred four transgressions in this area over the historical times. The first transgression occurred at 7500 a B.P., with the maxium sea level up to about 1 m above the present level. The second transgression occurred at 5750 a B.P., with the sea level possibly 4 m higher than the present. The third and fourth transgressions took place at 4650 a B.P. and 2600 a B.P. respectively, which lasted for a long time with multiple fluctuations. The fifth transgression is in process. It could be predicted that the sea level at Zhuhai would rise by 15-20 cm in the coming 50 years. 相似文献
910.