Branches and Scope of Geology Questions and Answers

Answer: A

Correct answer: 80 degrees, requiring ventilation and cooling

A normal gradient of about 30 degrees per kilometre on a surface temperature of 20 gives \( 20 + 60 = 80 \) degrees at 2 km. That is well beyond what can be worked in unaided, so ventilation and refrigeration become part of the design and a substantial part of the cost.

Answer: B

Correct answer: both the assertion and the reason are true and the reason explains the assertion

Both are true and the reason gives the mechanism. Because the same physical and chemical processes have operated throughout, a rock formed in the past can be interpreted by observing what produces such rocks today. Note what the principle does not claim - not that rates were constant, nor that no catastrophic events occurred, only that the processes were the same.

Answer: C

Deposition does proceed upward, but folding can overturn a sequence so completely that the oldest bed lies at the top. The law holds only where the strata have not been inverted, which must be established independently.

Answer: D

It maps a physical property continuously across a site, which interpolates between the points where boreholes gave hard information. Neither alone is sufficient: the boreholes calibrate the geophysics and the geophysics extends the boreholes.

Answer: A

Correct answer: the order in which two beds were laid down

Order is exactly what relative dating gives, and it does so securely from superposition and cross-cutting relationships. Ages in years, rates of accumulation and the duration of a period all require numbers, and numbers require radiometric or other absolute methods.