We walk out of the school into Jhansi's pediplain
, this last stage in the evolution of landforms, the final result of an infinity of erosion, exposing the earth's inner layers.
Pediplain is the result of inselbergs's destruction (Fig.
THE LANDSCAPE OF EXHUMED PEDIPLAIN landscape 1.1.1.
The entire watershed area can be classified into four important geomorphic units, namely, denudation hills, dissected pediment, valley fills, and pediplain
. The prime source of groundwater in the watershed area occurs under both phreatic and semiconfined conditions in the weathered and fractured granites.
The major geomorphologic features are alluvial plain, paleochannels, pediments, pediplain, valley fill, coastal plain, deltaic plain and denudational hill (Figure 3).
The moderate potential zone (25.33%) is dominated by geologic units of laterite, geomorphic units such as pediments, pediplain, coastal plains, soil units of entisols, medium lineament and drainage density.
Shallow weathered buried pediplain is a smooth surface of weathered shales and phyllites with less than five meters of thickness are generally covered with black soils with moderate to good ground water yields.
Area statistics of hydrogeomorphological features S.No Category Area Percent ([Km.sup.2]) Area 1 Piedmont Zone (PZ) 14.3 5.6 2 Moderately Weathered Pediplain (PPM) 13.1 5.1 3 Shallow Weathered /buried 77 30.4 pediplainPediplain (PPS) 3 Shallow Weathered Pediplain (PPS) 99 39.2 4 Moderately Weathered Pediplain (PPM/CQ) 7.1 2.8 5 Shallow Weathered Pediplain (PPS/CQ) 2.1 0.8 6 Pediment 2.2 0.8 7 Linear Ridge ( L/CQ) 3.3 1.3 8 Structural Hill (SH/CQ) 11.4 4.5 9 Linear Ridge (L/BQ) 0.8 0.3 10 Structural Hill (SH/BQ) 19.4 7.6 Table 3.
-- 1976 Rock Art of the Cobar Pediplain
in Central Western NSW, Australian Institute of Aboriginal Studies, Canberra.
Cortes (1999) and Cortes and Casas (2000) proposed that the formation of the Jiloca Depression is primarily related to erosional processes accompanied by the development of nested planation surfaces (pediplains
) on the western margin.
Other authors propose alternative interpretations, such as multiple stepped pediplains
developed during Paleogene to early Miocene times within the framework of compressive uplift (Gonzalez et al., 1998; Guimera y Gonzalez, 1998; Casas and Cortes, 2002), or Pliocene to Quaternary karstic corrosion surfaces (Gracia et al., 2003).