Shield volcano are cave-like volcanic straights formed by the hardening of overlaying lava. These structures help further the propagation of lava, as the walls of the tube insulates the lava within. Lava tubes can account for a large portion of shield volcano activity; for example, an estimated 58% of the lava forming Kīlauea comes from lava tubes. In some shield volcano eruptions, basaltic lava pours out of a long fissure instead of a central vent, and shrouds the countryside with a long band of volcanic material in the form of a broad plateau. Plateaus of this type exist in Iceland, Washington, Oregon,
Tenorio Volcano National Park Dantas Trail, which winds up the volcano and passes through forested terrain before eventually reaching the peak. Tenorio Volcano National Park Tenorio Volcano National Park () is a National Park in the northern part of Costa Rica, which forms part of the Arenal Tilaran Conservation Area. The jewel of the National Park is the volcano, from which it receives its name. The Tenorio Volcano was made part of the National Park in 1995 and is located about 26 miles northeast from the town of Fortuna in the Guanacaste Province. Tenorio Volcano consists of four volcanic peaks and two craters. One