Origin and Role of Kaolinization in Roll-Front Uranium Deposits and Its Response to Ore-Forming Fluids in the Yili Basin, China

Table 2

Average percentage content of clay minerals in host rocks from each geochemical zone.

Geochemical zones	Sampling depth (m)	Number	Framework grains (%)						Clay minerals (%)
			Qtz	Kfl	Pl	Cal	Dol	Clay	Kao	It	I/S
Oxidation
Strong oxidation zone	364–425.8	4	68.4	5.9	6.6	2.2	1.2	13.7	62.5	11.5	26
zone
Weak oxidation zone	320–623	14	67.4	7.5	6.3	1.9	1.8	15.1	69.8	11	19.2
Mineralized zone	456.5–604.9	4	66.2	6.2	5.2	3.3	1.6	17.5	72.5	10.2	17.3
Primary zone	367–650.5	9	67.5	5.9	8	5	2.7	10.9	50.7	19.3	30

Qtz, quartz; Kfl, potash feldspar; Pl, plagioclase; Cal, calcite; Dol, dolomite; Kao, kaolinite; It, Illite; I/S, illite/smectite mixed-layer.