Mess Lake Lava Field black young basalt. Its westernmost and southwesternmost ends are flanked by the Mess Creek Escarpment, forming a steep prominent cliff. This cliff exposes several layers of black columnar basaltic lava flows with distal rock fragments and pyroclastic deposits. Eruptions of the young Mess Lake Lava Field basalts cascaded down this steep lava cliff similar to what occurs at the island of Hawaii and covered some of the columnar basalt jointing. Near Mess Lake, inactive hot springs can be found and are most likely associated with the most recent eruptive activity in the Mess Lake Lava Field. Hot springs are closely
Hogg Rock Hogg Rock Hogg Rock is a tuya volcano and lava dome in the Cascade Range of northern Oregon, located close to Santiam Pass. Produced by magma with an intermediate andesite composition, it has steep slopes and thick glassy margins. Hogg Rock exhibits normal magnetic polarity and is probably about 80,000 years old. Hogg Rock lies south of Three Fingered Jack and north of Hayrick Butte, a somewhat larger tuya of similar age and composition. A tuya is a type of subglacial volcano, formed when lava erupts underneath an overlying glacier or ice sheet and then melts through to the surface