- Current Update, last updated Aug 6, 2014 07:43 :
Seismicity continued to be slightly elevated; deformation patterns may suggest renewed inflation.
Monitoring data through the month of July 2014:
Seismicity: Seismicity continued to be elevated over the average rates of the past 25 years-9 shallow events below summit area, 9 events to the west of Mokuʻāweoweo Crater (<13 km), 2 events to the north of Mokuʻāweoweo Crater, 23 shallow events on the Upper Southwest Rift (Sulfur Cone), 0 shallow events on the Lower Southwest Rift, 1 shallow event on the NE Rift Zone, 3 Deep Long Period Events.
Deformation: GPS data show a broad pattern of horizontal displacements suggesting renewed inflation, which may have started in April 2014, with an increase in rate in July. Displacement rates are still low compared to rates just after the 1984 eruption and during the height of the 2002-2009 inflation.
Gas: No significant changes in SO2, CO2 were recorded by the Mokuaweoweo gas and temperature monitors through July 16th, when network links were disrupted by a lightning storm that hit HVO. We're working to restore these links. Daily average fumarole temperature during the month continued to decline to about 73.5 C from 74 C through mid-month, still not back down to the 71.7 degrees average of several months ago.
- 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