GIS-based gully erosion susceptibility modeling, adapting bivariate statistical method and AHP approach in Gombe town and environs Northeast Nigeria

Geoenvironmental Disasters

Table 10 Showing FR values for geology classes

	factor classes	No. of points	% of points	class area	% of class area	Frequency ratio	Relative frequency
Geology	kerri kerri form	81,541.88	76.10	349,006	60.20	1.26	0.34
	Gombe sandstone	12,326.1	11.50	111,965	19.31	0.59	0.16
	Yolde formation	12,326.098	11.50	83,748	14.44	1.68	0.45
	Pindiga formation	948.1614	0.88	35,002	6.03	0.14	0.03
	sum	107,142.2	100	579,721	100	3.69	1