They divided it into four units which from base to the top included 1) conglomerates 2) lower quartzite 3) quartz schist
and 4) upper quartzite.
Prominent rock units include granite gneiss, migmatites, schist/ quartz schist
, porphyritic granite, fine-medium grained granite and charnockite.
- Hole G2P-3 0 to 150m Biotite quartz schist
with varying feldspar, garnet graphite, chlorite and pyrite, with minor pegmatites.
There are a variety of different types: clinozoisite-rich rock fragments, epidote-biotite quartz schist
, amphibole-biotite-clinozoisite-quartz schist, biotite-clinozoisite-quartz schist, clinozoisite-biotite-opaques-quartz schist, biotite-rich rock fragments, amphibole-biotite-opaques-clinozoisite-quartz-titanite rock fragment, chlorite or anthophyllite-biotite schist (some possibly with accessory tourmaline?), chlorite biotite schist, clinozoisite feldspar rock fragment, altered feldspar-titanite-biotite replaced amphibole-clinozoisite rock fragment, amphibole-rich rock fragments, and garnet-banded biotite quartz rock fragment.
TABLE 1 Soil Groups (5) Soil Group Parent material Chandler/Talledaga Hard talcose schist and mica schist Chester Micaceous schist; white quartzite present on uplands Edgemont Quartz schist
, quartzitic sandstone, quartzite conglomerate, pure quartzite Glenelg/Chester Micaceous schists Hagerstown/Duffield Limestone Highfield Metabasalt with considerable quartzite Linganore Hard slaty schist or phyllite Manor/Glenelg Thin, platty schistose rock Myersville/Fauquier Metabasalt Penn/Readington/Croton Red, Triassic-age sandstone and shale
These schistose rocks are mainly quartz schist and amphibole schist.
The Modal composition of the quartz schist and amphibole schist are shown in tables 1and 2.
Seven unaltered and fresh samples each of quartz schist and amphibole schist were analyzed for both major oxide and trace element concentrations at the Activation Laboratories, Canada, using the inductively coupled plasma analytical technique.
Average Si[O.sub.2] value in the quartz schist is high (95%).
The average values of MgO and Ti[O.sub.2] for the quartz schist are low (both less than 0.06%)
Average value for the quartz schist is 0.13% while that of the amphibole schist is 0.28%.
The Effon Psammite formation (Hubbard et al., 1966; De Swardt, 1953; Dempster, 1967; Caby and Boesse, 2001) comprises quartzites, quartz schists
and granulites which occur largely east of Ilesha and run for nearly 180 km in a NNE-SSW direction.