Nandyal Shale Fm
Lithology and Thickness
Claystone: Brown-gray, color-laminated shale-calcareous shale (Fig. image I). Internally 1-15 cm beds are with plane parallel laminations with streaks of fine sands and fading ripples. Thicker beds exhibit normal grading, and local development of mud clast conglomerate with sandy matrix. 50-100 m thick.
[Field photographs showing lithology and sedimentary features in the Kurnool Group. Banganapalle Quartzite Fm – (A) basal conglomerate of overlying granitic basement, and (B) thick matrix supported polymict conglomerate with apparent size grading. Narji Limestone Fm - (C) lower part with thin wavy bedded impure limestone, and (D) glauconitic sandstone interbeds in limestone; note pockets of lime pebble conglomerate. Owk Shale Fm - (E) Thinly laminated ash beds, and (F) transition from Owk Shale (lower half of photo) to Paniam Quartzite Fm. Paniam Quartzite Fm - (G) truncated wavy lamination. Koilkuntla Limestone Fm - (H) thin bedded argillaceous limestone, and (I) impure limestone-shale intercalation within the Koilkuntla Limestone Fm to Nandyal Shale Fm transition. (from Saha et al., 2016)]
Relationships and Distribution
Lower contact
The underying Koilkuntla Limestone Fm grades upward into the Nandyal Shale Fm (Fig. image I)
Upper contact
Not given.
Regional extent
GeoJSON
Fossils
Age
Depositional setting
Shallow marine. The sand deficient, mud dominated Nandyal Shale possibly represents deposition below storm wave base in a wide shelf, under tectonic quiescence.
Additional Information