
Clastic Dikes: Sand Dikes Intruding Bedrock
Clastic Dikes in Basalt Bedrock Sheeted dikes with sandy fills intrude downward into Miocene Columbia River Basalt in the Walla Walla...

Clastic Dikes: Formed by Lateral Spreading?
Lateral spreads. A network of lateral spread fractures in pavement formed by an earthquake. Peru 1970. USGS photo. Lateral Spreading: A...

Clastic Dikes: Dispelling a Periglacial Origin
What Does Periglacial Mean? "Periglacial" is a term that packs a punch. Like "tundra" or "permafrost", it stands in for a full suite of...