A weekly feature provided by scientists at the Hawaiian Volcano Observatory. Kilauea's south shore is . . . Less apparent is the comparably steep slope that continues into the submarine setting. There is little in our above-water experience that prepares us to comprehend such steep slopes in so short a distance. On our Big Island, the slope plunges away again beyond the 3-km lip, to reach the abyssal depths of 5.5 km.
Minor variations develop where lava enters the sea.
The lava builds a small promontory or bench. The shape of the bench is mimicked by the bathymetric contours as they bulge outward. The plunge of the slope remains equally steep, however. These lava flows coat the submarine slope but do little to lessen the steep gradient. Indeed, as the shoreline progrades slightly with each new lava flow, the net effect is to oversteepen the upper part of the slope even more.