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

Over the past week, lava flows have been active on the pali and coastal plain in two distinct lobes west of Kalapana. The easternmost of the active flow lobes destroyed a local resident’s home Jan. 13 and continues to advance slowly to the southeast near the end of Highway 130.

The western lobe is no longer entering the ocean. At Puu Oo, lava flows continue to erupt from a spatter cone in the north-central part of the crater floor, slowly filling it.

At Kilauea’s summit, the circulating lava lake in the collapse pit deep within the floor of Halemaumau Crater has been visible via Webcam throughout the past week.

Overnight Jan. 17-18, several large portions of the vent walls, including a 12 m (40 ft) wide piece of the Halemaumau crater floor, collapsed into the lava lake. The largest collapse caused a small explosion that littered the rim of Halemaumau crater directly above the vent with spatter up to 30 cm (1 ft) across.

The circulation pattern of the lava lake was interrupted by the explosion, and only a few short-lived increases in the height of the lava surface have occurred since. A small DI event, the first of 2011, began Jan. 19 and ended on the following day. Volcanic gas emissions remain elevated, resulting in high concentrations of sulfur dioxide downwind.

Three earthquakes beneath the Hawaiian Islands were reported felt during the past week.

A magnitude-3.4 earthquake occurred at 11:27 a.m. Saturday, Jan. 15 and was located 7 km (4 miles) southeast of Waikii at a depth of 15 km (9 miles).

A magnitude-3.5 earthquake occurred at 11:11 p.m. Monday, Jan. 17, and was located 2 km (1 mile) southwest of Kilauea summit at a depth of 1 km (1 mile).

A magnitude-3.2 earthquake occurred at 5:36 a.m. Wednesday, Jan. 19, and was located 13 km (8 miles) southwest of Mauna Loa summit at a depth of 13 km (8 miles).

Visit the HVO Web site (http://hvo.wr.usgs.gov) for detailed Kilauea and Mauna Loa activity updates, recent volcano photos, recent earthquakes, and more; call (808) 967-8862 for a Kilauea summary; email questions to askHVO@usgs.gov.