Biology Agriculture Aquaculture Horticulture Postharvest Forestry Geography Environment Health





Gravity fluctuations induced by magma convection at Kilauea Volcano, Hawai'i

submitted by gom 1 year and 8 months ago
Convection in magma chambers is thought to play a key role in the activity of persistently active volcanoes, but has only been inferred indirectly from geochemical observations or simulated numerically. Continuous microgravity measurements, which track changes in subsurface mass distribution over time, provide a potential method for characterizing convection in magma reservoirs. We recorded gravity oscillations with a period of ~150 s at two continuous gravity stations at the summit of Kilauea Volcano, Hawai‘i. The oscillations are not related to inertial accelerations caused by seismic activity, but instead indicate variations in subsurface mass. Source modeling suggests that the oscillations are caused by density inversions in a magma reservoir located ~1 km beneath the east margin of Halema‘uma‘u Crater in Kilauea Caldera-a location of known magma storage.


Topic: Geography

Add your comment

Please Login or Signup to leave a comment

Related stories

Continuous gravity measurements reveal a low-density lava lake at Kīlauea Volcano, Hawai‘i
submitted by omoloa 9 months ago - Topic: Geography
On 5 March 2011, the lava lake within the summit eruptive vent at Kīlauea Volcano, Hawai‘i, began to drain as magma withdrew to feed a dike intrusion and fissure eruption on the volcanoʼs east rift zone. The draining was monitored by a variety of continuous geological and geophysical measurements, including deformation, thermal and visual imagery, and gravity. Over the first ∼14 hours of ...

The role of viscous magma mush spreading in volcanic flank motion at Kīlauea Volcano, Hawai'i
submitted by rmocep 1 year and 1 month ago - Topic: Geography
Multiple mechanisms have been suggested to explain seaward motion of the south flank of Kīlauea Volcano, Hawai'i. The consistency of flank motion during both waxing and waning magmatic activity at Kīlauea suggests that a continuously acting force, like gravity body force, plays a substantial role. Using finite element models, we test whether gravity is the principal driver of long-term motion...



The shallow structure of Kilauea caldera from high resolution Bouguer gravity and total magnetic anomaly mapping: Insights into progressive magma reservoir growth
submitted by rmocep 10 months ago - Topic: Geography
We conducted total magnetic field and Bouguer gravity measurements to investigate the shallow structure beneath the summit caldera of Kīlauea Volcano, Hawai‘i. Two significant and distinctive magnetic anomalies were identified within the caldera. One is interpreted to be associated with a long-lived pre-historic eruptive centre, the Observatory vent, located ~1 km east of the Hawaiian Volc...

Tomographic image of melt storage beneath Askja volcano, Iceland using local microseismicity
submitted by tammol32 7 months ago - Topic: Geography
We use P- and S-wave arrivals from microseismic earthquakes to construct 3-D tomographic Vp and Vs images of the magma storage region beneath Askja's central volcano in the Northern Volcanic Zone of Iceland. A distinctive ellipsoidal low-velocity anomaly, with both Vp and Vs velocities 8–12% below the background, is imaged at 6–11 km depth beneath the caldera. The presence of a shallow ma...


Age, geology, geophysics, and geochemistry of Mahukona Volcano, Hawai`i
submitted by ksorovonon97 1 year and 10 months ago - Topic: Geography
The size, shape, and magmatic history of the most recently discovered shield volcano in the Hawaiian Islands, Mahukona, have been controversial. Mahukona corresponds to what was thought to be a gap in the paired sequence (Loa and Kea trends) of younger Hawaiian volcanoes (...

Conduit magma convection of a rhyolitic magma: Constraints from cosmic-ray muon radiography of Iwodake, Satsuma-Iwojima volcano, Japan
submitted by lode 1 year and 8 months ago - Topic: Geography
Quantitative re-evaluation of the muon radiography data obtained by Tanaka et al. (29) was conducted to constrain conduit magma convection at the Iwodake rhyolitic cone of Satsuma-Iwojima volcano, Japan. Re-evaluation of the measurement error considering topography and fake muon counts confirms the existence of a low-density body of 3m in diameter and with .9–1.gcm−3 at depths of 135–19m ...


First observations of the fumarolic gas output from a restless caldera: Implications for the current period of unrest (2005–2013) at Campi Flegrei
submitted by choll3 7 months ago - Topic: Geography
The fumarolic gas output has not been quantified for any of the currently deforming calderas worldwide, due to the lack of suitable gas flux sensing techniques. In view of resumption of ground uplift (since 2005) and the associated variations in gas chemistry, Campi Flegrei, in southern Italy, is one of the restless calderas where gas flux observations are especially necessary. Here we report t...

Deformations and slope instability on Stromboli volcano: Integration of GBInSAR data and analogue modeling
submitted by midenoj 1 year and 5 months ago - Topic: Geography
To understand the relationship between volcano deformations, magma overpressure and flank instability, the results of analogue experiments of slope instability and ground deformations, recorded by the GBInSAR system on the western flank of the Stromboli volcano during the period 2009–2011 have been analyzed. Analogue experiments that consider both the external (accumulation on the slope) and ...


Constraining volcanic inflation at Three Sisters Volcanic Field in Oregon, USA, through microgravity and deformation modeling
submitted by prestenibei 1 year and 6 months ago - Topic: Geography
Microgravity data were collected between 2002 and 2009 at the Three Sisters Volcanic Complex, Oregon, to investigate the causes of an ongoing deformation event west of South Sister volcano. Three different conceptual models have been proposed as the causal mechanism for the deformation event: (1) hydraulic uplift due to continual injection of magma at depth, pressurization of hydrothermal syste...

Small-Scale Temperature Fluctuations seen by the VeRa Radio Science Experiment on Venus Express
submitted by ntrapec 1 year and 7 months ago - Topic: Geography
The Venus Express Radio Science Experiment VeRa retrieves atmospheric profiles in the mesosphere and troposphere of Venus in the approximate altitude range of 40–90 km. A data set of more than 500 profiles was retrieved between the orbit insertion of Venus Express in 2006 and the end of occultation season no. 11 in July 201The atmospheric profiles cover a wide range of latitudes and local tim...