|
|
Country: | United States | |
| Subregion Name: | Oregon (USA) | ||
| Volcano Number: | 1202-17- | ||
| Volcano Type: | Volcanic field | ||
| Volcano Status: | Tephrochronology | ||
| Last Known Eruption: | 5450 BC ± 1000 years | ||
| Summit Elevation: | 1435 m | 4,708 feet | |
| Latitude: | 43.10°N * | 43°6'0"N | |
| Longitude: | 118.75°W | 118°45'0"W | |
| Diamond Craters volcanic field consists of a 60 sq km area of basaltic lava flows and numerous cinder cones and maars located between the SE Oregon town of Burns and Steens Mountain. A basaltic pahoehoe lava field is overlain by deposits from phreatomagmatic and strombolian eruptions that formed a late-stage central vent complex of about 20 craters and cones that densely fill a 1.1 x 1.6 km box-shaped caldera. The age of Diamond Craters is constrained to within 8400-6400 calibrated radiocarbon years Before Present by dated floodplain deposits below the lava flows and the oldest tephra deposit in a maar erupted through the lava flow (Sherrod 2011, pers. comm.). Structural doming at Diamond Craters has created a series of six overlapping topographic highs. The highest of these is known as Graben Dome; its 1435-m-high summit is cut by a NW-SE-trending graben 0.4 x 2.1 km long and 30 m deep. Lava flows on the eastern side of the volcanic field and scattered cinder cones and maars formed during the last stage of activity. | |||
