Video courtesy of Tropical Visions Video with air transportation by Paradise Helicopters.

The lava delta at KÄ«lauea Volcano’s Kamokuna ocean entry continues to grow. On May 23, activity was concentrated near the southeastern tip of the delta, creating a thick steam plume that afforded only occasional glimpses of lava entering the ocean. Small littoral bursts were common as molten lava interacted with the cool seawater. Many narrow cracks parallel to the sea cliff could be seen on the delta surface. Photo taken Tuesday, May 23, 2017 courtesy of USGS/HVO

A telephoto view of where the 61g lava tube exits the sea cliff. The upper portion of the firehose flow, visible from early January to late March 2017, is now crusted over, but lava within the tube continues to feed the growing lava delta. Photo taken Tuesday, May 23, 2017 courtesy of USGS/HVO

Zooming in even closer, the top of the crusted-over firehose flow can be seen. Cracks in the hardened tube surface reveal incandescent lava flowing though the tube. Fume from the degassing lava also escapes through these cracks. Photo taken Tuesday, May 23, 2017 courtesy of USGS/HVO

The March 5 breakout of the 61g flow is producing active surface flows on and at the base of the pali (cliff). The slow-moving pāhoehoe flow front (foreground) was approximately 400 meters (yards) beyond the base of the pali on the afternoon of May 23. An ‘a‘ā channel (center) made its way down the pali, along with other small breakouts and channels of ‘a‘ā and pāhoehoe scattered to the west of the main 61g lava tube (visible degassing at upper right). Photo taken Tuesday, May 23, 2017 courtesy of USGS/HVO

Time-lapse thermal image movie of Halemaumau Overlook Vent. May 18-25, 2017. Images courtesy of USGS/HVO

Time-lapse movie of Halemaumau Overlook Vent. May 18-25, 2017. Images courtesy of USGS/HVO

Time-lapse movie of Halemaʻumaʻu Overlook Vent from Hawaiian Volcano Observatory. May 18-25, 2017. Images courtesy of USGS/HVO

Time-lapse movie of KÄ«lauea Caldera from Hawaiian Volcano Observatory. May 18-25, 2017. Images courtesy of USGS/HVO

Time-lapse movie of Halemaumau Crater looking Southwest. May 18-25, 2017. Images courtesy of Hawaii Volcanoes National Park

(Activity updates are written by scientists at the U.S. Geological Survey’s Hawaiian Volcano Observatory.)

This past week, Kīlauea Volcano’s summit lava lake fluctuated in concert with summit inflation and deflation, with levels ranging around 17–35 m (56–115 ft) below the vent rim. On the East Rift Zone, the 61g flow remained active, with lava entering the ocean near Kamokuna and surface breakouts downslope of Pu‘u ‘Ō‘ō. These flows do not pose an immediate threat to nearby communities.

Mauna Loa is not erupting. During the past week, small-magnitude earthquakes were recorded, mostly from beneath the volcano’s summit caldera and upper Southwest Rift Zone at depths up to 5 km (3 mi). Microearthquakes also occurred on the east flank at depths of 5-13 km (3-8 mi). GPS measurements continue to show deformation consistent with inflation of a magma reservoir beneath the summit and upper Southwest Rift Zone. No significant changes in volcanic gas emissions were measured.

Two earthquakes were reported felt on the Island of Hawaiʻi during the past week. At 7:28 a.m. on May 22, a magnitude-3.3 earthquake occurred 12.4 km (7.7 mi) north of Nā‘ālehu at a depth of 10.7 km (6.6 mi). At 11:15 a.m. on May 18, a magnitude-3.2 earthquake occurred 10.7 km (6.6 mi) west of Kalapana at a depth of 7.2 km (4.5 mi).

Time-lapse movie of Pu’u ‘O’o Crater. May 18-25, 2017. Images courtesy of USGS/HVO

Time-lapse image movie from a research camera positioned on Holei Pali, looking east towards Lava Flow 61G and Kalapana. May 18-25, 2017. Images courtesy of USGS/HVO