海南岛南部沿岸地下水水化学要素变化及海水入侵特征  

VARIATION IN CHEMICAL ELEMENTS OF GROUNDWATER ALONG THE SOUTH COAST OF HAINAN ISLAND AND SIGNIFICANCE TO SEAWATER INTRUSION

作　　者：袁晓婕 黄向青[1,2] 甘华阳 黄磊[1,2] YUAN Xiaojie HUANG Xiangqing GAN Huayang HUANG Lei(Guangzhou Marine Geological Survey, China Geological Survey, Guangzhou 510075, China Key Laboratory of Marine Mineral Resources, Ministry of Land and Resources, Guangzhou 510075, China)

机构地区：[1]中国地质调查局广州海洋地质调查局,广州510075 [2]国土资源部海底矿产资源重点实验室,广州510075

出　　处：《海洋地质前沿》2017年第8期32-40,共9页Marine Geology Frontiers

基　　金：国土资源部海底矿产资源重点实验室开放基金课题(KLMMR-2014-A-07)

摘　　要：对位于海南岛南部滨岸测井地下水进行了大小潮周日取样及其化学测试。结果显示,化学要素含量及变化特征随潮期、测井位置而变化,由于所处环境的不同,QZ2和QZ5监测井的K^+、Na^+、Ca^(2+)含量相近,而Mg^(2+)的差异较明显,前者平均高出后者18.82%,表明QZ2监测井受到海水入侵。QZ2、QZ5监测井阳离子以Na+、阴离子以Cl^-占优,Na^+所占平均比例为83%~85%、Cl^-为87%~88%,显示出海水的影响;QZ3监测井以HCO_3^-占优,比例为62%~63%,Ca^(2+)也占据较大优势,为淡水所控制。QZ2、QZ5监测井SAR依次为57.95~63.24、57.20~63.13,QZ3监测井为2.17~4.42,前两者明显要高很多。QZ2、QZ5监测井地下水盐碱化风险程度很高,QZ3为一般。The data of 2014 from monitoring wells in South Coast of Hainan Island was studied during the times of neap tide and spring tide. Variation in chemical elements of the groundwater is adopted for revealing its relation with seawater intrusion. Our results show that chemical element concentra- tion varies with tidal cycles, location of wells and surrounding environment. In the wells of QZ2 and QZ5, the contents of K＋ , Na＋ , Ca2＋ are quite close, but Mgz＋ is obviously different. In the well QZ2, it is 18.82% higher than that in well QZ5, suggesting that the well QZ2 is more severely affected by seawater. Na＋ and C1- are the dominant ions in both the wells of QZ2 and QZ5. The average ratio of Na＋ is 83-85%, Cl- is 87-88%, showing effects of seawater. In the well QZ3, HCO3- is the dominant, the content is 62-63%, and Ca2＋ also occupies a large proportion, showing the predominance of fresh water. The SAR of QZ2 and QZ5 wells are 57.95-63.24 and 57.20- 63.13 respectively. However, it is 2.17-4. 42 in well QZ3, obviously lower than those in QZ2 and QZ5. As the conclusion, wells QZ2 and QZ5 have higher risk of salinization.

关 键 词：海南岛南部 地下水 化学要素 海水入侵 

分 类 号：P736.4[天文地球—海洋地质]