"The two-cycle Theory" of the origin of limestone caverns was proposed by

•  Davis

• Swinerton

• Gardner

• Mass wasting

All those processes which tend bring the surface of the lithosphere to a common level are collectively known as 

• Gradation 

• Degradation

• Aggradation

• Mass wasting

Which one of the following atmospheric layers reflects radio waves that are transmitted from the earth again back to the earth ?

• Mesophere

• Ionosphere

• Troposphere

• Stratosphere

164.

Which among the following was one of the forces respomsible for continental drift according to Wegener ?

• Tidal force

• Convection currents

• Tensional forces

• Compressional forces

The normal cycle of erosion is associated with

• Marine erosion

• Wind erosion

• River erosion

• Glacial erosion

Which among the following is one of the forces responsible for continental drift according to Wegner ?

• Tidal force

• Convection currents

• Tensional forces

• Compressional force

• a-4 , b-3 , c-2 , d-1

• a-2 , b-4 , c-1 , d-3

• a-4 , b-1 , c-2 , d-3

• a-3 , b-4 , c-2 , d-1

Most of the details of world's topography belongs to the 

• Pre-cambrian era

• Palazoic era

• Mesozioc era

• Cenozoic era

The valleys which drain in the same direction as the original consequent drainage but at the lower topographic levels and have developed with respect to new base levels are known as

• Resequent

• Obsequent

• Insequent

• Subsequent

The concept of 'base level erosion' was proposed by

• Davis

• Malott

• Johnson

• Powell