Environmental Engineering Reference
In-Depth Information
FIGURE 6.76
Slightly weathered granite and fresh granite. Mica in the specimen on the left has begun to decompose and
stain the rock with iron oxide (Paranagua, Parana, Brazil).
FIGURE 6.77
Granite corestones and spheroidal weathering in a sandy soil matrix (Itaorna, Rio de Janeira, Brazil).
downslope to accumulate in groups or in a matrix of colluvium at the base of the hill. They
can be of very large diameters as shown in
Figure 6.80.
On level terrain the boulders form
“tors” as illustrated in
Figure 6.75.
The presence of “corestones” can be very significant in foundation investigations
because of mis-interpretation that bedrock is at a higher elevation than actual.
