Erratum to: Environ Earth Sci DOI 10.1007/s12665-015-4271-4

The original article has been published inadvertently with some errors in Eq. 7 and Fig. 4. The corrected Eq. 7 and Fig. 4 are given below.

$$ F^{2} \left( {v,w,s} \right) = \frac{1}{{s^{2} }}\sum\limits_{i = 1}^{s} {\sum\limits_{j = 1}^{s} {\epsilon_{v,w} (i,j)^{2} } } $$
(7)
figure a