- Current Update, last updated Jun 11, 2013 06:54 HST:
Minor inflation of a shallow magma reservoir beneath Mauna Loa may be occurring. Seismicity rates were slightly elevated.
Deformation: Deformation of Mauna Loa continued to be dominated by southeasterly motion of the south flank. However, slow, localized uplift also continues near the summit caldera (~1cm/yr at MLSP) suggesting that some inflation of the shallow magma reservoir complex beneath the summit area is occurring.
Seismicity: Seismic activity within the southwest rift was slightly above background levels. HVO seismic networks detected 1 shallow event below summit area, 2 mid-crustal events (5-13 km) west and northwest of summit, 8 shallow events within the southwest rift, 1 shallow events on the northeast rift zone.
Gas: No significant changes in SO2, CO2 were recorded by the Mokuaweoweo gas and temperature monitors during May. Fumarole temperature varied between 72 and 74 degrees during the month.
- Volcanic History Overview: Massive Mauna Loa shield volcano rises almost 9 km above the sea floor to form the world's largest active volcano. Flank eruptions are predominately from the lengthy NE and SW rift zones, and the summit is cut by the Mokuaweoweo caldera, which sits within an older and larger 6 x 8 km caldera. Two of the youngest large debris avalanches documented in Hawaii traveled nearly 100 km from Mauna Loa; the second of the Alika avalanches was emplaced about 105,000 years ago (Moore et al. 1989). Almost 90% of the surface of the basaltic shield volcano is covered by lavas less than 4000 years old (Lockwood and Lipman, 1987). During a 750-year eruptive period beginning about 1500 years ago, a series of voluminous overflows from a summit lava lake covered about one fourth of the volcano's surface. The ensuing 750-year period, from shortly after the formation of Mokuaweoweo caldera until the present, saw an additional quarter of the volcano covered with lava flows predominately from summit and NW rift zone vents.
- Location: Hawaii and Pacific Ocean, HI
Elevation: 4170 m
Recent Eruption: 1984
- Hazard Assessments: Mullineaux, Donal Ray; Peterson, Donald W., 1974, Volcanic hazards on the Island of Hawaii, Open-File Report 74-239.
- Link to monitoring data: Recent Earthquakes in Hawaii Page
Volcanic Alert Level: NORMAL Aviation Color Code: GREEN