Site classification surface geology

Classification of sample sites by surface geological unit (Table 2) shows that the highest arsenic concentrations were found in the groundwaters from recent deltaic and alluvial deposits with more than half of the well waters having As >50 pg L in each of the Estuarine deposits, Chandina alluvium, deltaic silt and deltaic sand units. These are also amongst the most abundant deposits. 30.5% of the shallow wells in recent alluvial and deltaic units contained As >50 pg L . 

Based on surface geology The criteria for this type of classifications are based on the geologic age of the sediments. The different site classes as per geologic site classification are given in Table 1... 

Table 1. Site classification based on surface geology.

Site classification can be carried out by different schemes based on average shear wave velocity in the upper 30 m, surface geology and geo-... 

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