Sea cliff at Kamokuna ocean entry collapses

The “firehose” flow is no longer visible at the Kamokuna ocean entry, Hawaiian Volcano Observatory scientists reported Thursday.

However, spatter (bits of molten lava) and black sand flying through the steam plume indicated that lava was still flowing into the ocean and interacting explosively with seawater, according to geologist who hiked to the area to assess the status of the sea cliff on Thursday. Just below the left side of the steam cloud, a small shelf of the Kamokuna lava delta that survived the New Year’s Eve collapse can still be seen.

At about 12:55 p.m., a 98-by-16-foot portion of the block seaward of the crack fell into the ocean generating a noticeable, but not unusually large, wave propagating outward from the rockfall location. The crack was additionally widened by the collapse and was 3.3 feet wide after the collapse, an increase of 10 inches in the past day. Around 4 p.m., another collapse occurred but scientists have not verified yet what remains of the seaward block.

As a strong caution to visitors viewing the ocean entry (where lava meets the sea), there are additional significant hazards besides walking on uneven surfaces and around unstable, extremely steep sea cliffs. Venturing too close to an ocean entry on land or the ocean exposes you to flying debris created by the explosive interaction between lava and water, according to HVO.

Also, the new land created is unstable because it is built on unconsolidated lava fragments and sand. This loose material can easily be eroded away by surf, causing the new land to become unsupported and slide into the sea. In several instances, such collapses, once started, have also incorporated parts of the older sea cliff. This occurred most recently on Dec. 31. Additionally, the interaction of lava with the ocean creates a corrosive seawater plume laden with hydrochloric acid and fine volcanic particles that can irritate the skin, eyes, and lungs.