Occurrence of Attributes in Original Text

The text related to the cultural heritage 'Islands and Protected Areas of the Gulf of California' has mentioned 'Volcanic' in the following places:
Occurrence Sentence Text Source
The island of Isla Tortuga is one example of this ongoing volcanic activity.
In fact, many of the islands of the gulf are the result of volcanic eruptions that occurred during the early history of Baja California.
The islands and islets are mostly of volcanic origin.