Erosion tectonically active areas

The ocean surface represents the master base level for continental erosion and sedimentation. Given a sufficient p eriod of time, in the absence of tectonic processes, continents would presumably be eroded flat to about sea level. It is not surprising, therefore, that most tectonically quiet areas on continents tend to have low elevations and are often flat, whereas tectonically active areas, mostly mountain belts, have high elevations and steep slopes (Fig. 6-2 and... 

The existence of positive relief features and mountains is an almost self-explanatory indication that the rates of uplift of some continental sections have been much higher than the rates of denudation (Fig. 2). The rates of erosion that about balance or are slightly below the rates of uplift characterize the stable shield areas of South America, 10-20 mm ka and a tectonically active island Formosa (Taiwan), where uplift rates are as high as 103-104 mmka-1 (Stallard, 1988). 

Furthermore, during mid- and late-Tertiary times, the Llanos depression was subject to differential tectonic processes. Its central and eastern sectors have suffered from a moderate uplift causing subsequent pronounced erosion activities in the area, whereas in the western sector subsidence prevailed, which was then followed by intense sediment accumulation. 

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