What is the Difference Between Plate Tectonics and Continental Drift

The main difference between plate tectonics and continental drift is that plate tectonics describes the features and movement of Earth’s surface in the present and in the past whereas continental drift describes the drifting of Earth’s continents on the ocean bed.

Plate tectonics and continental drift are important theories in geology. The theory of plate tectonics is, in fact, developed based on the theory of continental drift. Therefore, these are two theories that describe closely related phenomena.

Key Areas Covered

1. What is Plate Tectonics 
     – Definition, Features
2. What is Continental Drift
     – Definition, Features
3. What is the Difference Between Plate Tectonics and Continental Drift
     – Comparison of Key Differences

Key Terms

Continental Drift, Plate Tectonics, Tectonic Plates

What is Plate Tectonics

Plate tectonics is the theory in geology that describes the features and movement of Earth’s surface in the present and in the past. This is a scientific theory that explains the large scale motion of seven large plates for about 3 billion years. This is a scientific model that is built on the theory of continental drift.

Figure 1: Different Plate Tectonics

The lithosphere is the outermost solid sphere of Earth. According to plate tectonics, this lithosphere is broken into tectonic plates. In other words, tectonic plates are the small pieces of large land areas of Earth. There are seven major plates on Earth, as well as many minor plates. Moreover, there is a relative motion in the boundaries where the plates meet each other, which describes the type of boundary. For example, there are convergent, divergent, or transform boundaries. Moreover, we can observe some activities such as earthquakes, volcanic eruptions, mountain building, etc. in these boundaries. The relative motion of two plates ranges from 0 to 100 mm (annually).

What is Continental Drift

Continental drift is a theory in geology that describes the drifting of Earth’s continents on the ocean bed. According to this theory, Earth’s continents have moved on the ocean bed over a long time period, appearing to be drifted across the ocean. Moreover, this concept was first developed by Abraham Ortelius in 1596. Later, this concept was independently and more completely developed by some other scientists.

Figure 2: Continental Drift in an Animation

At present, the evidence for these two theories is extensive. For example, we can observe similar plant and animal species around the shores of different continents and this suggests that these continents were once joined to each other.

Difference Between Plate Tectonics and Continental Drift

Definition

Plate tectonics is the theory in geology that describes the features and movement of Earth’s surface in the present and in the past. Continental drift, on the other hand, is a theory in geology that describes the drifting of Earth’s continents on the ocean bed.

Description

According to plate tectonics theory, Earth’s lithosphere is composed of different plates and they began to move a long time ago, but according to continental drift theory, there are continents on Earth which have drifted on the ocean bed.

Evidence

The presence of seven major continents and small islands is proof for plate tectonics theory while the occurrence of similar plant and animal species around the shores of different continents proves continental drift theory. 

Conclusion

In conclusion, plate tectonics and continental drift are important theories in geology. These are, in fact, two theories that describe closely related phenomena. Plate tectonics describes the features and movement of Earth’s surface in the present and in the past whereas continental drift describes the drifting of Earth’s continents on the ocean bed. Thus, this is the main difference between plate tectonics and continental drift. 

Reference:

1. Oskin, Becky. “What Is Plate Tectonics?” LiveScience, Purch, 19 Dec. 2017, Available here.
2. Andel, Tjeerd H. van, and J. Brendan Murphy. “Plate Tectonics.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 21 Mar. 2020, Available here.
3. “Plate Tectonics.” Wikipedia, Wikimedia Foundation, 28 May 2020, Available here.

Image Courtesy:

1. “Plates tect2 en” By Map:USGSDescription:Scott Nash – This file was derived from: Tectonic plates.png (Public Domain, Available here.
2. “Pangea animation 03” By Original upload by en:User:Tbower – USGS animation A08 (Public Domain) via Commons Wikimedia