Volcano Watching: How Maunakea Gravimetry Helps Observe Mauna Loa

The gravimeter measures the force of gravity on the Mauna Kea. These measurements are used to calibrate the instruments so that they can accurately monitor changes in gravity from the magma build-up in Mauna Loa (background). Photo by the United States Geological Survey taken December 10, 2020. (Public domain.)

Volcano Watch is a weekly article and activity update written by the scientists and affiliates of the Hawaiian Volcano Observatory of the US Geological Survey.

It’s five in the morning and a somewhat sleepy scientist is preparing to leave his Honomū home and head to the USGS Hawaiian Volcano Observatory (HVO) office on Kamehameha Street in Hilo. He yawns – not quite enough – he says goodbye to the dog that follows him in the kitchen and wonders why he woke up so early.

At the HVO office, he picked up two identical shoebox-sized devices – the gravimeter – and carried them in a USGS all-wheel drive vehicle. Today will be a long day driving from Hilo to the top of Mauna Kea and back twice.

But these days are essential, and any day you spend on the mountain is a good day, especially if the sky is clear and the views extend to the horizon. Between Hilo and the Mauna Kea summit, the HVO world would make about half a dozen times stop at a series of sites (standards) created beginning in the 1960s. In these parameters, two gravimeters will be used to measure the change of force in gravity.

Days like this are not particularly eventful; It consists of driving from one measurement site to another and waiting for the gravimetrics to settle at each new location. It’s full of audiobooks, public Hawaiian radio, and listening to wind sounds. These are not the thrilling days of trekking the Kīlauea caldera or flying in a helicopter to the summit of Mauna Loa.

The article continues below M.

Gravitometers, which are essentially a very accurate pendulum, can measure the change in the force of gravity to one in a billion of the force you feel each day. This force varies based on the distance and amount of mass between the device (or between you) and the center of the Earth.

The article continues below M.

Just like atmospheric pressure, the force of gravity changes according to your height. For example, the higher your height (like driving over a mountain), the further away you are from the center of the Earth (and its mass), and the weaker the force of gravity. This elevation effect is the primary contribution to changes in measured gravitational pull in Mauna Kea. Changes in gravity aren’t as noticeable as the change in the atmosphere (it’s hard to breathe at the top), but the average person also weighs about a third of a pound less – equivalent to the weight of an orange – at the summit of Mauna Kea than they do on Hilo!

Since the 1970s, slight changes in time-varying gravity (microgravity) have been measured at the active volcanoes of Mauna Loa and Colauea to determine whether magma is building up in magma reservoirs. These intrusive magmas often open up and fill cracks and / or empty spaces, causing a net increase in the mass of a volcano that can be measured with a gravimetric. Gravimetry is an independent way to confirm whether a continuous uplift, such as the one occurring at Mauna Loa since 2014, is caused by new magma creeping into the volcano.

The accuracy and sensitivity of gravimetric devices make them extremely sensitive and require regular calibration. As the dominant effect we measure from changes in altitude, our ability to measure volcanic changes at the high altitudes of Mauna Loa (13,680 feet or 4,170 meters) requires us to calibrate instruments at similar altitudes in Mauna Kea where there is currently no effect of volcanic activity (The last volcanic eruption was more than 4,500 years ago.) Without Mauna Kea, we would have to send gravimeters to California for calibration, leaving them vulnerable to damage on their long journey.

The article continues below M.

The opportunity to calibrate HVO gravimetric devices on Mauna Kea provides the ability to design a gravity monitoring program to help understand volcanic disturbances in Mauna Loa. Besides ground deformation and earthquakes, future gravity surveys could help discover how much magma is slowly being supplied to the Mauna Loa shallow magma storage system. On the island of Hawaii, Mauna Kea and Mauna Loa played important roles in the past; Today, they work together to help inform us of future volcanic activity.

Volcano activity updates

Kīlauea volcano erupting. USGS Volcano Alert Level at WATCH (https://www.usgs.gov/natural-hazards/volcano-hazards/about-alert-levels). Kīlauea updates are released daily.

Lava activity is limited to Halemaʻumaʻu with lava erupting from a ventilation hole on the northwest side of the crater. Laser rangefinder measurements this morning, April 22, indicate that the lava in the western (active) part of the lake is 741 feet deep, with the eastern part of the lava lake hardening at the surface. The top tilt gauges have recorded little change in the past 24 hours. The sulfur dioxide emission rates measured on April 14 were 950 tons / day. Earthquakes remain stable, as tremor rises. For the most recent information on the eruption, see https://www.usgs.gov/volcanoes/kilauea/current-eruption.

Mauna Loa does not erupt and is still at Volcano Alert Level. This alert level does not imply that a volcano eruption is imminent or that progression to an eruption from the current level of turbulence is a certainty. Mauna Loa updates are released weekly.

Last week, around 175 small-scale earthquakes were recorded below Mauna Loa; Most of these occurred below the summit and higher elevations at depths of about 5 miles. GPS measurements continue to show a slightly extended crest distortion pattern over the past week. Gas concentrations and fumarol temperatures both at the summit and in the sulfur cone in the southwest rift region remain stable. Web cameras do not show any changes to the landscape. For more information on the current monitoring of Mauna Loa volcano, see: https://www.usgs.gov/volcanoes/mauna-loa/monitoring.

There were 3 events with 3 or more hairy reports in the Hawaiian Islands over the past week: M3.0 earthquake 1 km (0 mi) ENE from Pāhala at 22 miles depth on April 21 at 2:09 AM HST, M2. 8 earthquake 3 miles east of Pahala at a depth of 21 miles on April 20 at 11:08 AM HST, and the M3.2 earthquake 14 miles east of Honunau-Nabuobu at a depth of 2 miles on April 16 at 7:46 PM HST.

HVO continues to monitor both the ongoing Kīlauea and Mauna Loa eruptions for any signs of increased activity.

Visit the HVO website for previous Volcano Watch articles, Kīlauea and Mauna Loa updates, volcano photos, maps, recent earthquake information, and more. Email questions to [email protected]

.

What Are The Main Benefits Of Comparing Car Insurance Quotes Online

LOS ANGELES, CA / ACCESSWIRE / June 24, 2020, / Compare-autoinsurance.Org has launched a new blog post that presents the main benefits of comparing multiple car insurance quotes. For more info and free online quotes, please visit https://compare-autoinsurance.Org/the-advantages-of-comparing-prices-with-car-insurance-quotes-online/ The modern society has numerous technological advantages. One important advantage is the speed at which information is sent and received. With the help of the internet, the shopping habits of many persons have drastically changed. The car insurance industry hasn't remained untouched by these changes. On the internet, drivers can compare insurance prices and find out which sellers have the best offers. View photos The advantages of comparing online car insurance quotes are the following: Online quotes can be obtained from anywhere and at any time. Unlike physical insurance agencies, websites don't have a specific schedule and they are available at any time. Drivers that have busy working schedules, can compare quotes from anywhere and at any time, even at midnight. Multiple choices. Almost all insurance providers, no matter if they are well-known brands or just local insurers, have an online presence. Online quotes will allow policyholders the chance to discover multiple insurance companies and check their prices. Drivers are no longer required to get quotes from just a few known insurance companies. Also, local and regional insurers can provide lower insurance rates for the same services. Accurate insurance estimates. Online quotes can only be accurate if the customers provide accurate and real info about their car models and driving history. Lying about past driving incidents can make the price estimates to be lower, but when dealing with an insurance company lying to them is useless. Usually, insurance companies will do research about a potential customer before granting him coverage. Online quotes can be sorted easily. Although drivers are recommended to not choose a policy just based on its price, drivers can easily sort quotes by insurance price. Using brokerage websites will allow drivers to get quotes from multiple insurers, thus making the comparison faster and easier. For additional info, money-saving tips, and free car insurance quotes, visit https://compare-autoinsurance.Org/ Compare-autoinsurance.Org is an online provider of life, home, health, and auto insurance quotes. This website is unique because it does not simply stick to one kind of insurance provider, but brings the clients the best deals from many different online insurance carriers. In this way, clients have access to offers from multiple carriers all in one place: this website. On this site, customers have access to quotes for insurance plans from various agencies, such as local or nationwide agencies, brand names insurance companies, etc. "Online quotes can easily help drivers obtain better car insurance deals. All they have to do is to complete an online form with accurate and real info, then compare prices", said Russell Rabichev, Marketing Director of Internet Marketing Company. CONTACT: Company Name: Internet Marketing CompanyPerson for contact Name: Gurgu CPhone Number: (818) 359-3898Email: [email protected]: https://compare-autoinsurance.Org/ SOURCE: Compare-autoinsurance.Org View source version on accesswire.Com:https://www.Accesswire.Com/595055/What-Are-The-Main-Benefits-Of-Comparing-Car-Insurance-Quotes-Online View photos