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主要通过黄河口悬浮物中有机碳和无机碳的含量,表征黄河调水调沙入海的泥沙在黄河口外近海的扩散范围。结果表明:黄河口入海前泥沙中的颗粒无机碳(PIC),颗粒有机碳(POC)具有稳定性,分别为(1.75×0.28)%和(0.51×0.08)%;在悬浮物含量约为30 mg/L时,黄河口临近海区悬浮物中的PIC、POC含量分别出现突跃性降低和升高趋势,叶绿素分析表明,POC含量的升高是由于浮游植物对颗粒有机碳贡献的结果,同时正构烷烃轻重比值ΣC20-/ΣC20+和碳优势指数(CPI)值也分别增加和降低;X衍射发现悬浮物浓度低于30 mg/L时,黄河泥沙在悬浮物中所占比例迅速下降,从而造成悬浮物中PIC突跃性下降;因此,黄河口近海悬浮物含量30 mg/L可以被认为是陆源和海源颗粒物对黄河口近海区悬浮物贡献的有效分界线。调水调沙入海的泥沙在黄河口外近海表层主要扩散到河口以南海域,而底层扩散范围主要集中在河口以北和河口以南海域,这些泥沙最终可能停留在莱州湾中部。 相似文献
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通过2004年4月,2004年9月,2005年9月,2006年4月4个航次,结合2003年8月对河道感潮带的连续同步观测,对低流量下黄河口有机碳的输运特征进行了考察。结果发现:黄河输入至河口的悬浮物中颗粒有机碳(POC)含量约为0.51%,主要以陆源输入为主,几乎不受季节变化影响,由于大量POC含量低的陆源泥沙的稀释作用,浮游植物对总颗粒有机碳的贡献只有在悬浮物含量(TSS)<200mg/L时才能显现出来;黄河口TSS超过455mg/L时,有机碳入海以颗粒有机碳为主;反之,以溶解有机碳为主。黄河口悬浮物在低盐度区沉降作用前后的中值粒径降低,Φ>16μm的悬浮物的沉降作用比Φ<16μm的悬浮物更为剧烈,POC含量随悬浮物粒径的降低而升高,黄河携带的颗粒有机碳80%以上集中在Φ<16μm的TSS中;低流量下,黄河口最大混浊带对POC的过滤效率为65%,混浊带对POC的过滤效应能造成黄河口POC的有效通量被高估;由于受黄河口沉积物向水体解析DOC的影响,在盐度小于10时,DOC几乎不受海水稀释作用的影响,但在盐度大于10的区域DOC与盐度表现出良好的负相关关系,黄河口枯、丰水期淡水端溶解有机碳的有效浓度分别高于实测最高值20%和10%左右,从而造成黄河口DOC有效通量被低估。 相似文献
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CHEN Bin LIU Shuwen WANG Rui CHEN Zhichao LIU Chaoqun Key Laboratory of Orogenic Belts Crustal Evolution MOE School of Earth Space Sciences Peking University Beijing 《《地质学报》英文版》2006,80(6)
1 Introduction The tectono-thermal evolution of the North China Craton (NCC) in Late Archean to Paleoproterozoic times has long been attractive to many researchers (Wan et al., 2000; Zhao et al., 2000, 2002; Guo et al., 2001; Liu et al., 2002; Zhai and Liu 2003; Zhai, 2004; Yu et al., 2004; Kr?ner et al., 2005; Wilde et al., 2005). Zhao et al. (2000, 2002) proposed a tectono-thermo framework for the evolution of the NCCbased on detailed petrological and geochronological data, and they … 相似文献
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<正>The podiform chromitites in the Luobusa ophiolite,Southern Tibet,have received much attention because of the presence of ultrahigh-pressure minerals,such as microdiamonds(Bai et al.,1993;Yang et al.,2007;Xu et al.,2009),coesite(Yang et al.,2007)and highly reduced metal phases(Bai et al.,2000;Robinson et al.,2004).The 相似文献
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《吉林大学学报(地球科学版)》2015,(Z1)
<正>越来越多的研究结果表明,Re在不同硫化物间存在一定的分配规律。例如:辉钼矿的Re含量往往比共生的黄铁矿(Li et al.,2011)或黄铜矿(Zhu and Sun,2013)高3~5个数量级;黄铁矿的Re含量普遍比闪锌矿(Morelli et al.,2004)和方铅矿(Stein et al.,2000)高3~30倍;铅锌矿床中闪锌矿的Re含量又明显高于方铅矿(Liu et al.,2015)。这些很可能与Re在硫化物中分配系数的差异,即各硫化物载Re能力的 相似文献
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《矿物学报》2013,(Z2)
<正>目前,对于斑岩铜矿的研究主要集中于探讨温度区间为200800℃范围内矿床的成因问题,例如岩体形成时代及顺序、矿化和热液蚀变时代以及热液活动时限等(Barra et al.,2002;Masterman et al.,2004;Deckart et al.,2005;Pollard et al.,2005;Campbell et al.,2006;Mao et al.,2006;Baumgartner et al.,2009;Redmond and Einaudi,2010;Sillitoe and Mortensen,2010;Vry et al.,2010;Shen et al.,2012;Zhu et al.,2012)。虽然这些问题很重要,但是仍然不足以全面的认识和 相似文献
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针对整个渤海海域悬浮泥沙分布全貌研究的不足,基于2000-2004年连续5年的354个SeaWiFS反演的渤海表层悬沙浓度资料,经多年月平均得到其季节变化特征;通过经验正交函数分解,给出其空间模态及时间系数,揭示渤海表层悬浮泥沙的空间分布特征及其随时间的变化。渤海表层悬沙浓度除秦皇岛海域外近岸高,离岸低,辽东湾东岸浓度远大于西岸;冬季浓度最高,春秋次之,除河口海域外夏季浓度最低;河口海域冬夏季均为浓度高值区。经验正交分解显示第一空间模态反映渤海悬沙浓度的总体分布特征,其显著变化周期为12个月,显示渤海表层悬沙的季节变化特征。第二空间模态反映黄河入海径流对渤海表层悬沙浓度分布格局的影响, 其周期为6个月,代表黄河口海域悬沙浓度的变化周期。第三模态显示渤海不同海域悬沙浓度的增加或减小过程并不同步,存在明显的位相差异。 相似文献
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正1 Introduction Vegetation indices (VIs) derived from satellite observations are an essential source of information for operational monitoring of the Earth's vegetation (Qu et al.,2018;Yan et al.,2008).However,soil background dramatically affects the performances ofⅥs (Baret and Guyot,1991;Gilabert et al.,2002;Huete,1988;Qi et al.,1994).So soil-adjustedⅥs (Baret and Guyot,1991;Gilabert et al.,2002;Huete,1988;Qi et al.,1994) are 相似文献
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Zircon SHRIMP Dating for the Weiya Pluton, Eastern Tianshan: Its Geological Implications 总被引:18,自引:4,他引:18
ZHANG Zunzhong GU Lianxing WU Changzhi LI Weiqiang XI Aihua WANG Shuo State Key Laboratory of Mineral Deposit Research 《《地质学报》英文版》2005,79(4):481-490
1 Introduction Voluminous literature has resulted from study of the geology and tectonic evironments of post-orogenic granitoids in eastern Tianshan (He et al., 1995; Han et al., 1997; Gu et al., 1999, 2001; Li et al., 2003; Chen et al., 2004). Previous contributions (Hu et al., 1997; Li et al., 2003) indicate that major events of continental collision in northern Xinjiang occurred around 300 Ma. Then, the tectonics converted from compression to extension, resulting in the uplifting of th… 相似文献
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Several thrust faults have been mapped in theYanshan belt ,as the thrust structure was first iden-tified by Wong (1928) (Ji et al .,2005 ; Wang et al .,2005a ;Davis et al .,2001 ,1998 ; Yang et al .,2001 ;Zheng et al ., 2000 ; Chen, 1998 ; Zhang et al .,1986 ; He ,1957 ;Chern and Hsiung,1935) .Becausethe Archean basement was widely involved in thethrust systemof the Yanshan belt ,domestic popularrecognition emphasized the thick-skinned characteris-tics and li mited horizontal displacement… 相似文献
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Relic UHP Structures in Dabie-Sulu Region, China:Structural Expression and Geodynamic Significance 总被引:3,自引:0,他引:3
Suo Shutian Zhong Zengqiu You Zhendong Zhou Hanwen Faculty of Earth Sciences China University of Geosciences Wuhan China 《中国地质大学学报(英文版)》2000,11(3)
INTRODUCTIONIn recent years a num ber of detailed m ineralogical- petro-logical studies have been carried out on the UHP and HPmetamorphic belts in the Dabie- Sulu region,central China(see review papers by Jahn,1999;Ernst and L iou,1999;Wallis et al.,1999;Hacker et al.,1996 ;L iou et al.,1996 ;Cong et al.,1994) . Various tectonic evolution models for theUHP belt in the Dabie- Sulu region have been constructed(e.g.,Webb etal.,1999;Hacker et al.,1996 ;Cong et al.,1994) .However,as … 相似文献
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1 Introduction According to recent researches, the North China Craton consists of three parts: the eastern block, western block and central zone (Zhao, 2001; Wilde et al., 2002). Paleoarchean continental blocks and zircon residuals have only been found in a few regions, such as Anshan, East Liaoning (Liu et al., 1992; Song et al., 1996; Wan et al., 2002, 2005), Caozhuang, East Hebei (Liu et al., 1992) and Xinyang, West Henan (Zheng et al., 2004), which are mainly distributed in the east… 相似文献