Question

Which of the following is true of earth's coastlines?

O there are few inputs that directly affect them beyond tidal action.
O they are relatively young and undergoing continuous change.
O they have the oldest landforms on the planet.
O earth's coastlines show a remarkable degree of similarity across the planet.

Answer 1

Earth's coastlines are relatively young and undergoing continuous change, influenced by tides, geological activity, and the accumulation and reworking of sediments since the rifting of Pangaea.

Step-by-step explanation:

The correct statement about Earth's coastlines is: they are relatively young and undergoing continuous change.

Earth's coastlines are dynamic regions where the intertidal zone changes with each tidal cycle, alternating between being submerged and exposed. This zone can include different types of environments, such as sandy beaches, rocky shores, or mangrove forests, all adapting to the tidal shifts. The forces influencing coastal changes are not limited to tides; they also include geological activity, such as volcanic eruptions, erosion, and movements of the continental plates.

For example, the Coastal Plain along the Atlantic Ocean and the Gulf of Mexico has accumulated sediments since the rifting of Pangaea. These sediments are constantly reworked by these geological processes. Furthermore, Earth's crust is the most geologically active of all the terrestrial planets, continuously reshaping coastlines through various dynamic processes.