Isostasy refers to the state of balance between large upstanding areas of the Earth's surface such as mountain ranges and plateaus. True or False?

True

The less dense materials of the Earth’s surface, known as ___, float over denser magma, referred to as ___.

Sial; sima

Explain how isostatic adjustment is evidenced in Scandinavian countries post the Pleistocene ice age.

Isostatic adjustment is ongoing in Scandinavia.

• Uplift of raised beaches observed.

• Glacial melting causes crust rebounding.

• Finland's land has risen 250 meters.

Pierre Bouguer's observations during his expedition suggested that the gravitational attraction of the Andes was ___ than expected based on their mass.

Much smaller

True or False: George Everest's survey noted that the gravitational force of the Himalayas was stronger than anticipated, affecting latitude determination.

False. The force was less attractive, causing deflection of the plumb bob.

The concept of isostasy is primarily related to the balance of ___ among different landforms.

Gravitational attraction

The principle of flotation as applied by Sir George Airy suggests that for every part of the Earth's crust above the substratum, there must be ___ parts submerged below.

For every 1 part of the Earth's crust above the substratum, there must be about 6 parts submerged below.

True or False: Airy's concept includes the idea that the density of land columns changes with depth.

False. Airy's concept states that the density remains uniform with depth.

In Airy's experiments, the demonstration with iron and wood pieces illustrated the idea that different materials will sink to varying depths in a fluid due to their ___ and the principle of flotation.

Density

Pratt's concept proposes that density varies only in the ___ and not in the ___ and ___ of the Earth.

Lithosphere; pyrosphere; barysphere

True or False: According to Pratt's theory, the height of relief features is directly proportional to their density.

False; Pratt's theory states that density decreases with increasing elevation.

What is the principle of compensation in Pratt's theory?

Principle of Compensation 

• equal pressure at the depth of compensation

• Denser columns indicate height adjustment.

• Essential for understanding mass distribution.

The plane of compensation is estimated to be located at a depth of about ___ kilometers below the Earth's surface.

100 kilometers

True or False: Hayford and Bowie’s concept of isostasy is more closely aligned with Airy's views than with Pratt's.

False. Hayford and Bowie's concept aligns more closely with Pratt's.

Joly's concept of compensation in geology proposes a zone of compensation that is approximately ___ kilometers thick.

16 kilometers

True or False: Joly's idea aligns more closely with the plane of compensation proposed by Hayford and Bowie.

False - Joly's concept aligns more closely with Airy's concept, suggesting a zonal rather than linear phenomenon of compensation.