Controlled burn helps native landscape

From Big Island News: Controlled burn helps native landscape
HAWAII VOLCANOES NATIONAL PARK, Hawaii: 130 acres burned at the bottom of Chain of Craters Road in the Hawaii Volcanoes National Park… all on purpose.

The controlled burn, taking place in Kealakomowaena, will regenerate the growth of native pili grass and other indigenous plant species, as well as maintain a cultural landscape once occupied by families living in the Kealakomo ahupua‘a.

There were no closures because of the burn, and park visitors and normal park activities were not be impacted.

Kealakomowaena is an island of vegetation, or kīpuka, spared by recent lava flows in the middle of the Kealakomo ahupua‘a. Officials say Hawaiians thrived in this coastal lowland area, growing sweet potatoes, harvesting fish and drying salt. House sites, trails, lava rock walls and agricultural plots are found throughout Kealakomowaena. The controlled burn was conducted by an eight-person fire crew, in a manner to help maintain the traditional landscape of the area.

The national park says controlled burning is part of a comprehensive restoration plan for the coastal lowland ecosystem at Hawai‘i Volcanoes National Park.

Here is the latest update on the Kilauea volcano eruption, courtesy the USGS Hawaiian Volcano Observatory, posted on August 24:

Activity Summary for past 24 hours: Inflation slowed. At the summit, the lava lake continued with drain-and-fill cycles. In the middle east rift zone, the lava level continued to rise within Pu`u `O`o crater but there was still no sign of activity from the west flank vents. Seismicity, other than the episodic tremor bursts associated with the fill-and-drain cycles, was low. Gas emissions remained elevated from summit and rift zone vents. All lava activity remained within Hawai`i Volcanoes National Park and posed no direct hazard to any developed areas.

Past 24 hours at Kilauea summit: The lava level continued to fluctuate in 15-20 minute-long fill-and-drain cycles, each fill bringing the lava level to a high point below the inner ledge (the ledge is 75 m or 250 ft below Halema`uma`u Crater floor); lava fills the vent cavity bottom from the southeast and also drains toward the same place. The most recent (preliminary) sulfur dioxide emission rate measurement was 500 tonnes/day on August 19, 2011. Small amounts of ash-sized tephra, including fresh spatter bits, continued to be wafted within the plume and deposited on nearby surfaces.

The summit tiltmeter network recorded continued weak inflation. The summit GPS network recorded extension since Aug. 17. Seismic tremor levels were episodically high during the draining part of fill-and-drain cycles. Sixteen earthquakes were strong enough to be located within Kilauea volcano – two within the upper and middle east rift zone and fourteen on south flank faults (including a flurry of 9 earthquakes that occurred between 9:15-10:40 pm last night.

Seismic energy from the Peru magnitude-6.8 earthquake was recorded on our seismometers at 7:58 am HST this morning, about 12 minutes after it occurred; The Pacific Tsunami Warning Center has issued an Information Bulletin saying “A DESTRUCTIVE TSUNAMI WAS NOT GENERATED BASED ON EARTHQUAKE AND HISTORICAL TSUNAMI DATA.”

Background: The summit lava lake is deep within a ~150 m (500 ft) diameter near-vertical cylindrical vent inset within the east wall and floor of Halema`uma`u Crater and its level fluctuates from about 70 m to more than 150 m (out of sight) below the floor of Halema`uma`u Crater. The vent has been mostly active since opening with a small explosive event on March 19, 2008.

Past 24 hours at the middle east rift zone vents: Lava continued to cover more of the floor and slowly fill Pu`u `O`o Crater. There was no sign of lava activity from the west flank vents.

The tiltmeter on the north flank of Pu`u `O`o Cone continued to record weak inflation. GPS receivers on opposite sides of Pu`u `O`o cone recorded a gentle transition to very weak extension. Seismic tremor levels were low. The most recent (preliminary) sulfur dioxide emission rate measurement was 200 tonnes/day on August 19, 2011, from all east rift zone sources.

Background: The eruption of Kilauea’s middle east rift zone started with a fissure eruption on January 3, 1983, and has continued with few interruptions through Pu`u `O`o Crater or vents within a few kilometers to the east or west. In early August, the crater floor collapsed to a depth of about 75 m (245 ft) below the east rim as lava burst from vents on the west flank of Pu`u `O`o cone. A DI tilt event a few days later cut off supply to Pu`u `O`o and the west flank vents; lava reappeared in Pu`u `O`o Crater on August 21st.

Past 24 hours within the lower east rift zone: There were two earthquakes recorded in this area with magnitudes less than 1.5.

Background: Residents reported several felt earthquakes in this area between August 4th and 15th.