GENERAL GEOLOGY

GEOLOGY

STRATIGRAPHY

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Rock layers must be deposited BEFORE they can be bent or folded.
A
true
B
false
C
Either A or B
D
None of the above
Explanation: 

Detailed explanation-1: -The Law of Original Horizontality suggests that all rock layers are originally laid down (deposited) horizontally and can later be deformed. This allows us to infer that something must have happened to the rocks to make them tilted. This includes mountain building events, earthquakes, and faulting.

Detailed explanation-2: -An upward fold is called an anticline, while a downward fold is called a syncline. In many areas it’s common to find a series of anticlines and synclines (as in Figure 12.5), although some sequences of rocks are folded into a single anticline or syncline.

Detailed explanation-3: -Folds result from the slow deformation of rocks. This happens deep underground where the rocks are under pressure and temperatures are higher. Folded rocks are common in mountain ranges like the Alps, Himalayas and the Scottish Highlands.

Detailed explanation-4: -Folding-Folding occurs when tectonic processes put stress on a rock, and the rock bends, instead of breaking. This can create a variety of landforms as the surfaces of the folded rocks are eroded. Anticlines are folds shaped like an arch, and synclines are shaped like the letter ‘U. ‘

Detailed explanation-5: -Figure 10.9: Folds are a result of ductile deformation of rocks in response to external forces. 2. Layered rocks folded into arches are called anticlines whereas troughs are referred to as synclines.

There is 1 question to complete.