South Korea most of which is not arable. Lowlands, located primarily in the west and southeast, make up only 30% of the total land area. About three thousand islands, mostly small and uninhabited, lie off the western and southern coasts of South Korea. Jeju-do is about off the southern coast of South Korea. It is the country's largest island, with an area of . Jeju is also the site of South Korea's highest point: Hallasan, an extinct volcano, reaches above sea level. The easternmost islands of South Korea include Ulleungdo and Liancourt Rocks (Dokdo/Takeshima), while Marado and Socotra Rock are the southernmost
Jackson Volcano Jackson Volcano Jackson Volcano is an extinct volcano beneath the city of Jackson, Mississippi, under the Mississippi Coliseum. The uplifted terrain around the volcano forms the Jackson Dome, an area of dense rock clearly noticeable in local gravity measurements. E.W. Hilgard published his theory of an anticline beneath Jackson in 1860 due to his observations of surface strata. The dome contains relatively pure carbon dioxide which is used in oil production in Gulf Coast oil fields. The noble gas data suggests mantle origins with a date of 70 million years for the Jackson Dome intrusion. Geologists have evidence of repeated