Question

Difference between block disintegration and granular disintegtation

Answer 1

a) Block disintegration
- It occurs in well-jointed rock such as granite.
- It is particularly effective in areas with great diurnal range of temperature (10ºC to 15ºC or more) and
barren rocks without a protective vegetation cover, e.g. in desert regions.
- Rocks are split along the joints into large rectangular-shaped blocks.
b) Granular disintegration
- It is process of physical or mechanical weathering due to repeated heating and cooling as a result of
temperature changes.
- Rocks usually compose of different types of minerals. The dark coloured minerals e.g mica in granite,
absorb more heat and so heated up faster. Light coloured minerals e.g. quartz, feldspar, can reflect light
and heated up slower.
- As a result of alternate expansion and contraction of minerals in rocks causes the rock to break down
into small pieces.