Lava lava flows slowly (0.25 mph), with maximum speeds between 6–30 mph on steep slopes. An exceptional speed of 20–60 mph was recorded following the collapse of a lava lake at Mount Nyiragongo. The physical behavior of lava creates the physical forms of a lava flow or volcano. More fluid basaltic lava flows tend to form flat sheet-like bodies, whereas viscous rhyolite lava flows forms knobbly, blocky masses of rock. General features of volcanology can be used to classify volcanic edifices and provide information on the eruptions which formed the lava flow, even if the sequence of lavas have been buried
Boring Lava Field quartzite-pebble xenoliths (rock fragments enveloped in a larger rock during the latter's development and solidification) can be observed among local cinder specimens, dating from Miocene to Pliocene Troutdale deposits. While the volcanic rock of Boring Lava was being emplaced over rock from the Troutdale formation, there was deformation that uplifted and dropped fault blocks to the southeast of Portland. Along the Washougal River, a large landslide occurred as a result of failure due to the Boring lava pushing down on rock from the Troutdale formation. Intrusions of Boring Lava formed outcrops at Highland Butte, La Butte, and potentially in the