Falls Lake Trail - Section 1

Figure 1-A.  Block of banded Raleigh gneiss at beginning of trail.  Rock was excavated from a bit east of here.

Raleigh gneiss

Falls Lake Trail - Section 1

Figure 1B.  Ridge outcrop of Falls leucogneiss, trail point 1-B.

Link to addtional photographs of the Falls leucogneiss.

 

Falls leucogneiss
Falls Lake Trail - Section 1

Figure 1-I1.  Long creek outcrop at trail point 1-I.

Crabtree terrane gneiss
Falls Lake Trail - Section 1

Figure 1-I2.  Gneiss of the Crabtree terrane at trail point 1-I.  The small folds in the upper portion of the photo indicate the rocks were sheared in a right-lateral fashion (the upper parts moved to the right relative to the lower.  A pegmatite dike cuts across the gneiss from lower left to upper right.  It is thinned and offset in the same sense.

Crabtree terrane gneiss folds

Falls Lake Trail - Section 1

Figure 1-I3.  Small asymmetric folds in this outcrop resemble the letter Z, indicating right-lateral shear.  Rock features such as these, that tell the sense of motion in an ancient fault zone are known as kinematic indicators.

folds

Falls Lake Trail - Section 1

Figure 1-I4.  Boudinage in a pegmatite dike.  The rigid pegmatite was stretched and pinched into segments resembling sausages.

boudinage

Falls Lake Trail - Section 1

Figure 1-I5.  Here, a layer of amphibolite (metamorphic rock with hornblende and feldspar) has been pinched into a series of fat sausage-shaped boudins.

boudinage 2