雷州半岛东岸地下水Br^-变化及其与宏量离子的关系研究

Variation of Br-in groundwater and its relationship with other main ions along eastern coast of Leizhou peninsular

依据雷州半岛东岸J1、J2测井地下水潮周期取样测试数据,对Br-含量、变化及其与其它宏量离子的关系进行了分析。结果显示:Br-主要来源于海水侵染,测井基本类型为Na+K·Ca·Mg-Cl·SO4,J2为Na+K·Ca·Mg-Cl·SO4·HCO3。J1测井Br-平均含量为11.69~14.35 mg/L,J2测井Br-平均值约为J1的一半,各测井Br-统计特征随测次而有所变化。进一步结合Br-/Cl-比值和测井环境,认为J1更具有海洋相,为海水入侵混合稀释型,J2为河口-海洋相互作用型;Br-相对变幅与Cl-、SO42-等海相阴离子相近,说明Br-也同样积极参与海水入侵;Br-与各宏量离子的相关性随测井而异,Br-与阳离子的比值以Na+的最低,K+的最高,Mg2+居于其间;毫克当量比值区间频率多表现为左偏、坦峰、尖峰的分布形态,尤其是J2测井,但γBr-/γK+的比值接近正态。毫克当量比值的相关性与质量比值相关性是保持一致的,Br-/Na+、Br-/Cl-线性关系良好,并进行了最小二乘线性拟合。

According to the lab data on groundwater samples during two tidal cycles from monitoring wells J1 and J2 along eastern coast of Leizhou Peninsular , the paper analyzed the anion Br -'s concentration , variation and relationship with other main ions .The results demonstrate that Br -comes mainly from sea-water intrusion, and the basic types of measured well are Na +K· Ca· Mg-Cl· SO4 , and the types of J2 is Na+K· Ca· Mg-Cl· SO4· HCO3;the average content of Br -in J1 is 11.69~14.35mg/L and the concentration of Br -in J2 is almost half in J1's.Br -statistical characteristics every well change with the number of measurement .Combined with the ratio of Br -/Cl -and the invironment of measured well , it is thought that J1 primarily has sea-phase and J2 has river-sea phase in term of Br -/Cl -;Br -owns al-most the same relative amplitudes with Cl -and SO4 2-,which show Br -also actively takes part in the process of seawater intrusion;the correlation of Br -with other ions also varies with wells and the ratio of Br-to Na +is the lowest among the ratio of Br -to cations.the highest is K +;the ratio of Br -to Mg2+is in the meantime .The frequency in the region of milligram equivalent ratio chiefly appears the distribu-tion forms of left lean, sharp peak and flat peak , especially in well J2, the ratio ofγBr -/γK+is close to normal .The relativity of milligram equivalent ratio and mass equivalent ratio is consistent .The linear rela-tionship between Br -/Na +and Br -/Cl -is good.The paper finally made linear LST fitness .