One of the most important geographic and geological features of the Pacific Realm is volcanoes. Volcanoes have been instrumental in creating this realm. For example, we can see that there are many volcanoes in the islands of the Western Pacific. These include volcanoes on large islands like those of New Zealand, Indonesia, and the Philippines. They also include volcanoes and volcanic activity on small islands such as Pagan in the Northern Mariana Islands and Iwo Jima in Japan. It is also important to note that the small islands of the Pacific Realm owe their very existence to volcanoes. For example, the Hawaiian Islands are a chain of volcanic islands. In addition, the atolls that make up countries such as the Marshall Islands are the remnants of ancient volcanoes.
A major geographic feature of the Pacific Realm is the fact that much of it is made up of widely dispersed islands settled by people from only a very few ethnic groups. The islands of Micronesia, which are dispersed throughout an ocean area the size of the continental US, are all inhabited by members of one ethnic group. The islands of Polynesia, as far apart as New Zealand and Hawaii, are inhabited by Polynesians. This indicates that there has been significant migration by a few groups in this realm.
These are a few of the most important geological and geographical facts about the Pacific Realm.