(BIVN) – A series of recent USGS Hawaiian Volcano Observatory photographs document the latest activity at Kīlauea Volcano, which continues to erupt at its summit and from the Puʻu ʻŌʻō vent on its East Rift Zone.

At the summit, where the lava lake in Halema’uma’u was measured at 79 ft below the Overlook crater rim this morning. There was no significant change in ground tilt over the past day, with little change in the level of the lake, scientists report.

Clear weather provided good views of the lava lake on July 20. USGS captured this image of “crustal foundering, in which pieces of the thin, flexible lake crust sink beneath the surface.”

The episode 61g lava flow from Puʻu ʻŌʻō continues to enter the ocean at Kamokuna. Surface flows are active above the pali, with continued activity on the coastal plain. These flows pose no threat to nearby communities, USGS says.

On July 21, the front of this coastal plain breakout was 0.2 miles wide, and roughly 1.2 miles from the closest points in the emergency access road. The eastern side of the flow front was outside of the Hawaii Volcanoes National Park boundary, and there were many scattered sluggish pāhoehoe breakouts (pictured above). The western side, inside of the National Park, had less active pāhoehoe breakouts.

Scientists say several large cracks have developed in the lava delta, running parallel to the coastline and spanning the width of the delta. “These cracks increase the likelihood of a large delta collapse,” USGS warns.

The large coast-parallel crack that spans the width of the delta (seen from lower-left to upper-right of image) remains prominent, USGS says.