Lava Beds National Monument Butte is just outside the boundary of the monument, the Callahan flow is in Lava Beds and is the youngest flow in the monument. Spatter cones are built out of thicker lava. The lava is thrown out of the vent and builds, layer by layer, a chimney surrounding the vent. Fleener Chimneys and Black Crater are examples of spatter cones. Roughly ninety percent of the lava in the Lava Beds Monument is basaltic. There are primarily two kinds of basaltic lava flows: pahoehoe and 'a'a. Pahoehoe is smooth, often ropy and is the most common type of lava in Lava
Boring Lava Field Boring Lava Field The Boring Lava Field (also known as the Boring Volcanic Field) is an Plio-Pleistocene volcanic field with cinder cones, small shield volcanoes, and lava flows in the northern Willamette Valley of the U. S. state of Oregon. Located southeast of downtown Portland, the field got its name from the town of Boring, Oregon, which lies just to the southeast of the most dense cluster of lava vents. The zone became active about 2.7 million years ago, with long periods of activity interspersed with quiescence. Its last eruptions took place about 57,000 years ago at the Beacon Rock