What term did Alfred Wegener use to describe the ancient supercontinent that existed before the continents split?

Pangaea

The vast ocean that surrounded the supercontinent Pangaea is known as ___.

Panthalassa

True or False: According to Wegener, Pangaea began to split approximately 200 million years ago.

True

Fill in the blank: The two large continental masses formed after Pangaea split are called ___ and ___.

Laurasia and Gondwanaland

What was the primary argument presented by Alfred Wegener regarding the distribution of continents?

He argued that all continents were once part of a single landmass that later drifted apart.

The matching of the shorelines of Africa and South America is an example of ___ evidence supporting the theory of continental drift.

Geological

True or False: The earliest marine deposits along the coastlines of South America and Africa are of Cretaceous age.

False. The earliest marine deposits along these coastlines are of Jurassic age.

The presence of tillite in the Gondawana system indicates ___.

Extensive glaciation in the past

Placer deposits are formed from ___ and are key in understanding the historical geology of continents.

The accumulation of valuable minerals through sedimentary processes

Fill in the blank: Radiometric dating allows for the correlation of rock formations from different continents across the ___ .

Ocean

The occurrence of rich placer deposits of gold in Ghana is due to the erosion of ___ from the Brazil plateau.

Gold bearing veins

True or False: Fossil distribution of identical species across land masses suggests a former contiguous land connection.

True

The skeletons of Mesosaurus are found in South Africa and Brazil, which are currently separated by ___ kilometers.

4,800 km

Identical species of plants and animals found on either side of marine barriers present a problem in ___ studies.

Biogeography

Fill in the blank: The hypothesis of a landmass called 'Lemuria' was proposed to explain the distribution of ___ found in India, Madagascar, and Africa.

Lemurs

What two forces did Wegener propose were responsible for the drifting of continents?

Pole-fleeing force and tidal force.

Fill in the blank: The polar-fleeing force is related to the ___ of the Earth, which has a bulge at the equator.

Rotation

True or False: Wegener believed that the forces causing continental drift were effective over short geological time scales.

False. Wegener believed these forces would become effective when applied over many million years.

What was the primary source of evidence for continental drift before post-war studies?

Distribution of flora and fauna or deposits like tillite.

Fill in the blank: Arthur Holmes discussed the possibility of ___ currents operating in the mantle, generated by thermal differences.

Convection

Short Answer: How did the mapping of the ocean floor contribute to the understanding of continental drift?

It provided new dimensions for the study of the distribution of oceans and continents.

True or False: The convectional current theory was widely accepted by contemporary scientists as a reason for continental drift.

False. This theory was an attempt to provide an explanation for the forces, leading to the rejection of the continental drift theory.

The ocean floor is segmented into three major divisions: continental margins, deep-sea basins, and ___ ridges.

Mid-oceanic

True or False: The rocks from the oceanic crust are generally older than those from continental areas.

False; the rocks from the oceanic crust are much younger than those from continental areas.

What are deep-oceanic trenches, and why are they significant in oceanography?

Deep-oceanic trenches are areas of considerable interest as they represent the transition between oceanic and continental regions, often associated with tectonic activity and subduction zones.