Description

From Hopkins (1963) ^[1] : “The name "Gosling volcanics" is proposed for a group of basaltic and andesitic lava flows and endogenous domes that overlie the silt mantle on the Imuruk volcanics and that are overlain locally by the Camille and Lost Jim lava flows. The originally smooth surfaces of pahoehoe flows of the Gosling volcanics have been brecciated by frost riving to depths of at least 10 feet in most places, and the flows now consist of higher areas of openwork rubble interspersed with low-lying areas of rubble mixed with silt. Progressively younger flows have progressively larger proportions of areas underlain by openwork rubble and progressively smaller areas underlain by rubble mixed with silt. The formation is named for Gosling Cone, located at the source vent of a typical lava flow of the Gosling volcanics (pl. 1 in original text).”
“The Twin Calderas indent the summit of a broad lava dome at the site of a relatively long-lived vent. The dome stands 400 feet above lowlands to the south, west, and northeast. The two collapse calderas are 1,700 and 2,500 feet in diameter and 50 and 120 feet deep. Flat-floored sector grabens extend north from the northeast caldera and south from the southwest caldera (fig. 11 in original text). The caldera walls lie at the angle of repose for coarse rubble, and little solid bedrock can be seen. Exposures in the southwest caldera show, however, that the walls transect the smooth-surfaced pahoehoe-lava flow forming the surface of the lava dome. Near the top of the wall, the lava flow is composed of flow units 0.2 to 0.5 foot thick separated by thin zones of agglomerate. At greater depth the wall exposes flow units 2 to 6 feet thick.”