Department of Petroleum Engineering and Geosciences, Petroleum Training Institute, Effurun, Warri, Nigeria.
Department of Geology and Petroleum Studies, Western Delta University, Oghara, Nigeria.
Environ Monit Assess. 2019 Sep 6;191(10):617. doi: 10.1007/s10661-019-7788-2.
Delta State of the Niger Delta, Nigeria, is an oil exploration and production region that is characterized by huge revenue generation but with its attendant waste generation and oil spillage that impact the environment. The variability in the hydrochemical characteristics, hydrochemical controlling processes and quality in space has been investigated. The pH of the groundwater samples ranged from slightly acidic to slightly alkaline nature. Biological oxygen demand and chemical oxygen demand of the coastal area are higher than those of the inland area indicating more domestic and industrial contamination. Total dissolved solid values across the region indicated fresh and brackish water for the coastal area and fresh water only for the inland area. The orders of abundance of the cations and anions for the coastal and inland areas are Ca>Mg>Na>K/Cl>HCO>SO>NO and Na>Ca>K>Mg/HCO>Cl>NO>SO respectively. A Piper diagram identified four hydrochemical facies, namely CaHCO, NaHCO, NaCl and CaMgClSO. Ionic cross plots and correlation matrix revealed that the groundwater chemistry of the inland area is predominantly influenced by silicate weathering and ion exchange processes while those of the coastal area are influenced by silicate weathering, ion exchange processes and seawater tidal flushing. The groundwater from the coastal area is more polluted by heavy metals than those from the inland area. The observed variability may be attributed to effects of industrial wastes and exploration activities. In terms of water quality for domestic and irrigation, the groundwater of the coastal and the inland areas are not generally potable and suitable as drinking and irrigation water sources.
尼日利亚尼日尔三角洲的三角洲州是一个石油勘探和生产地区，其特点是收入巨大，但随之产生的废物生成和溢油对环境造成了影响。已经研究了地下水在空间上的水化学特征、水化学控制过程和质量的可变性。地下水样本的 pH 值范围从微酸性到微碱性。沿海地区的生物需氧量和化学需氧量高于内陆地区，表明有更多的生活和工业污染。整个地区的总溶解固体值表明沿海地区为淡水和微咸水，内陆地区为淡水。沿海和内陆地区的阳离子和阴离子丰度顺序分别为 Ca>Mg>Na>K/Cl>HCO>SO>NO 和 Na>Ca>K>Mg/HCO>Cl>NO>SO。Piper 图确定了四种水化学相，即 CaHCO、NaHCO、NaCl 和 CaMgClSO。离子交叉图和相关矩阵表明，内陆地区的地下水化学主要受硅酸盐风化和离子交换过程的影响，而沿海地区则受硅酸盐风化、离子交换过程和海水潮汐冲刷的影响。与内陆地区相比，沿海地区的地下水受重金属污染更严重。观察到的变化可能归因于工业废物和勘探活动的影响。就生活用水和灌溉用水的水质而言，沿海和内陆地区的地下水一般不适宜作为饮用水和灌溉水源。
