Kauai's Origion

The Island of Kauai is part of the Hawaiian island chain that sits near the middle of the Pacific plate. The islands were made from earthquakes in the plate which caused fissures near a hotspot allowing magma to flow upwards. The magma builds upon itself until it reaches sea level, creating an island. The magma that reached above sea level became the base of Kauai, also know as a shield volcano.

This type of volcano is low in elevation and has slow lava flow from eruptions. the magma poured down the sides and and continued to create a land base. Over the time span of 5 million years the beautiful island of Kauai was formed.  The plate which contains the Hawaiian hotspot moves slowly over time and eventually the magma source is cut off from one island and begins creating a new one. The main island of Hawaii is the only island in the chain that has constant magma influence from the hotspot beneath. The other islands would need some large eruptions to cause major magma flow again.

http://www.pdc.org/iweb/volcano_history.jsp