Table 16.1.

Geological succession of the Cuddapah Basin (Nagaraja Rao et al. 1987)

Age (Ma)GroupFormationThickness (m)Units
1090–500 (?)Kurnool GroupNandyal ShaleKoilkuntla LimestonePaniam QuartziteOwk ShaleNarji LimestoneBanganapalli Quartzite450ShaleLimestoneQuartziteShale–OcherousLimestoneConglomerate, quartzite
-------------------- Unconformity --------------------
2000–870Cuddapah SupergroupSrisailam Quartzite300Quartzite and shale
-------------------- Unconformity --------------------
Nallamalai GroupCumbum (Pullampet) Formation
Bairenkonda (Nagari) Quartzite
2000
5500
Phyllite, slate, quartzite, dolomite and shale
Quartzite, shale, conglomerate, quartzite and shale
-------------------- Unconformity --------------------
Chitravati GroupGandikota Quartzite
Tadpatri Formation
Pulivendla Quartzite
300
4600
1–75
Quartzite and shale
Shale, tuffs, quartzite and dolomite
Conglomerate and quartzite
-------------------- Unconformity --------------------
Papaghni GroupVempalle Formation
Gulcheru Quartzite
1900
28–210
Dolomite, chert and quartzite with basic flows and intrusions
Conglomerate, arkose, quartzite and shale
Archaean to Proterozoic---Unconformity (western margin)---
Dharwar (Archaean)
---Tectonic Contact (eastern margin)---
Eastern Ghats/Nellore Schist Belt (Proterozoic)