Volcano Watch: Hualalai is third most active volcano in Hawai`i

Reprinted from here.  Brought to you by Tour Guide and our new, comprehensive GPS/Internet/3G navigation App for iPhones and iPod Touch available today at iTunes!

View of Hualalai Volcano, Hawai`i, looking SE. Photograph by J. Kauahikaua on December 30, 1996.

The West Hawai`i Today issue for September 11, 2009, contained a letter to the editor titled “Hualalai is a real and present threat.” The writer’s main point was that “Hualalai is the ‘secret in the closet’ that nobody wants to talk about,” that Hualalai is under-monitored, and that, should Hualalai erupt, there is no evacuation plan.

The letter writer’s concerns about Hualalai were valid, but he was not aware of HVO’s current efforts and plans to improve the monitoring of Hualalai. We hope to shed some light on recent and future activities planned for Hualalai.

Hualalai is the third most active volcano on Hawai`i Island behind Kīlauea and Mauna Loa, according to the Hawaiian Volcano Observatory’s (HVO) Web site (http://hvo.wr.usgs.gov/), and attained national ranking of “High Threat” for active volcanoes in the U.S. (see http://pubs.usgs.gov/of/2005/1164/).

In the ranking, there were 37 volcanoes nation-wide that were highest-priority targets for improved monitoring; Kīlauea and Mauna Loa were included in this group. Furthermore, 21 additional volcanoes were found to be under-monitored and were regarded high priority for improved monitoring; Hualalai is in this group.

What is the basis for this ranking? Hualalai has erupted three times in the last 1,000 years, the most recent eruption occurring in 1801. An intense and damaging seismic swarm in 1929 marked a failed eruption. In the same interval, Mauna Loa and Kīlauea have each erupted more than 150 times, and Haleakala has erupted at least 10 times. Hualalai was rated a higher threat than Haleakala, due to the extent of development (airport, power station, etc.) and the larger population living on the volcano’s flanks.

Is Hualalai under-monitored? In 2005, HVO and the Pacific Tsunami Warning Center (PTWC) each had one seismometer on the volcano, and bi-annual deformation surveys were conducted by our staff. With the permission of Kamehameha Schools, a continuous GPS receiver was installed near the summit in late 2006. In 2009, HVO still has one seismometer and uses two instruments operated by PTWC for eruption monitoring, and we continue the bi-annual surveys. Plans for the next two years include upgrading our seismic site and adding a new one.

We routinely scrutinize all available satellite imagery daily, including visual and thermal images to indicate any significant visual and temperature changes, or increased gas emissions. Moreover, radar scans several times each year can pinpoint any ground deformation that may be a precursor to volcanic activity. The radar scans are so sensitive that several small areas of subsidence were detected after the October 15, 2006, Kiholo earthquakes.

The conclusion from evaluating all of these data is that there have been no signs of swelling, major subsidence, temperature changes, gas emissions, or unusual seismic activity on Hualalai that would indicate volcanic activity in the near future. Nevertheless, we continue to look for any changes.

If the rankings were done today, Hualalai would be nearly fully monitored.

We agree with the letter writer that “the more people know about Hualalai, the more will be prepared.” In 2004, University of Hawai`i at Manoa (UHM) scientists published two studies on Kona community’s perception of volcanic risk and preparedness for lava flows from Hualalai and Mauna Loa. They concluded that “current community understanding and preparedness… falls short of that required for a volcanic crisis, particularly for those eruptions with short onset and high effusion rates on steep slopes that would impact Kona in just a few hours…”

There are several reasons for the lack of understanding, but foremost may be the constant influx of new residents who haven’t educated themselves about volcanic hazards. The primary mission of the U.S. Geological Survey’s Hawaiian Volcano Observatory is to monitor the active volcanoes in the State of Hawai`i. Through our Web site, public forums, and newspaper articles, we strive to disseminate information on the volcanoes and their hazards.

The people of Kona should know that we are keeping an eye on Hualalai and that if there are any changes (in its eruption status), we will let the public know!

Kīlauea Activity Update

Lava continues to erupt from the TEB vent, on Kīlauea’s east rift zone and flow through tubes to the ocean at Waikupanaha. A deflation-inflation cycle this past week resulted in a reduction of lava supply for several days, followed by a resumption of flow on Wednesday, Sept. 30. Breakouts from the tube system started at that time, and these surface flows remain active at the top of Royal Gardens subdivision. The flows are mostly staying close to the breakout point along the east margin of the flow field.

Faint glow above the vent at Kīlauea’s summit has been visible at night. A portion of the Halema`uma`u vent cavity collapsed on Saturday, Sept. 26, followed by the appearance of an active lava pond deep within the vent cavity on the night of Tuesday, Sept. 29. Volcanic gas emissions remain elevated, resulting in high concentrations of sulfur dioxide downwind.

Four earthquakes beneath Hawai`i Island were reported felt this past week. A magnitude-2.3 earthquake occurred at 12:30 p.m., H.s.t., on Friday, September 25, 2009, beneath Kilauea’s summit at a depth of 6 km (4 miles). Two earthquakes occurred on Sunday, September 27-a magnitude-2.1 earthquake at 9:52 a.m., H.s.t., located 7 km (4.3 miles) N of Kailua at a depth of 8 km (5 miles) and a magnitude-2.3 earthquake at 10:22 p.m., H.s.t., located 7 km (4.3 miles) ENE of Honaunau at a depth of 6 km (3.7 miles). A 1.6-magnitude earthquake at 7:11 p.m. H.s.t., on Wednesday, September 30, was located 15 km (10 miles) NW of Mauna Kea’s summit at a depth of 25 km (16 miles).

Visit our Web site (http://hvo.wr.usgs.gov) for detailed Kīlauea and Mauna Loa activity updates, recent volcano photos, recent earthquakes, and more; call (808) 967-8862 for a Kīlauea activity summary; email questions to askHVO@usgs.gov.

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Planning on visiting the Big Island Volcanoes, hiking the beautiful summits or going to see the flowing lava?  Tour Guide Hawaii is proud to announce the release of their new iPhone and iPod Touch App available at iTunes…this App will help you plan your trip to Hawaii, help you decide what you want to see, how you want to see it and help you get there with GPS, interactive maps and on-board driving instructions.  In addition to concentrating on Hawaii’s volcanoes, beaches and waterfalls, the Tour Guide App presents hours of interesting videos and information about many other places of historical, cultural and recreational interest, giving you a sense of the people, the natural history and the unique specialness of each destination.  The information is so comprehensive and complete they even tell you where all the public restrooms are!

We highly recommend all Big Island visitor’s who have iPhones or an iPod Touch check out our App on iTunes; we think you’ll agree it’s far better than old-fashioned, cumbersome maps or expensive guide books that seem to be out of date before they are printed.  See it today!

Frank’s Big Island Travel Hints #10: Hawaii Volcanoes National Park

Frank’s Big Island Travel Hints #10: Hawaii Volcanoes National Park
by Frank Burgess, brought to you by Tour Guide Hawaii

Frank Burgess Filming at the End of Chain of Craters Road, Hawaii Volcanoes National Park: Photo by Donald B. MacGowan

Tour Guide Hawaii is proud to announce the release of their new iPhone and iPod Touch App available at iTunes…this App will help you plan your trip to Hawaii, help you decide what you want to see, how you want to see it and help you get there with GPS, interactive maps and on-board driving instructions.  The Tour Guide App presents hours of interesting videos and information about places of historical, cultural and recreational interest, giving you a sense of the people, the natural history and the unique specialness of each destination.  The information is so comprehensive and complete they even tell you where all the public restrooms are!  What else will Tour Guide help you find?  Let’s look at a trip south from Kona along the Hawaii Belt Road to Hawaii Volcanoes National Park…Tour Guide will not only help you find many amazing sights along the way, it will tell you all about them, what to take and what to expect.

Today’s hints cover the area from Kona to Hawaii Volcanoes National Park, and the first few sites of interest within the Park. Driving along the Kona Coast and then south east through Ka’u, through tropical rainforest, across mysterious savanna and recent lava flows,  there several fantastic places to stop and explore, but there is also a lot of lovely, open countryside for several miles, so enjoy the panoramic views. Your Tour Guide download from iTunes will give you more detailed information about this area.

Let’s Go to Hawaii Volcanoes National Park!

About a two hour straight drive from Kona, going south, brings you to the Hawaii Volcanoes National Park. If you have a Golden Eagle Pass your entrance is free. If not, it is only $10.00 per carload to enter the park. The rangers at the gate will give you detailed maps of the area.

Super tip: Your receipt will give you free access to the National Park for seven days.

My first suggestion is to go to the Kilauea Visitors Center and the Jagger Museum. This will give you a nice overview of the park and rangers are there to answer questions. This spot also looks over the majestic Halemaumau Crater. Tour Guide will get you to the park and lead you to more than 50 sites. It is also possible that our state bird, the Nene Goose, will be huddled in the parking lots. They are protected as an endangered species, so be careful when parking nearby.

Another great place to visit is the Volcano Art Center. It may seem a strange, but the Volcano Art Center boasts one of the best collections of art in the whole state. World renowned artist in various media are on display as well as theatrical and musical performances.

There is only one restaurant in the park proper, and that is the Volcano House. Built as a lodge in the mid 1800’s, the Volcano House has hosted dignitaries, politicians, sports heroes and movie stars from all over the world. This grand edifice sits right on the lip of Halemaumau Crater and the views from her restaurant are stunning. Tour Guide will give a complete history of how it came to be. The food is good and the prices are reasonable. Bicycle rentals are also available near the lodge.

Crater Rim Drive is a great driving introduction to the park. It encircles the Halemaumau Crater and, for only an 11 mile drive, passes through several dramatic climate zones. You will encounter arid desert, grass savannah, and into tropical rainforest; this loop can easily be done in forty minutes. However, you will want to take more time to appreciate the beauty and majesty of one nature’s most awesome wonders. Tour Guide will suggest short to medium hikes and bicycle trails as well as over 50 historic and geologic sites to visit within the park.

If you are up for some hiking, Tour Guide will lead you to the trail for Waldron Ledge Overlook. This short hike is through the Ohia and fern jungles, shaded most of the way, and can be done on bicycle as well. From this vantage point one can see the active vent, Kilauea Iki, and breathtaking views of the coast.

Along the Crater Rim Drive you will also see many steam vents and the Sulfur Banks. This is where water seeps into crevices and meets the molten magma about a half mile below the surface, is super heated, and returns to the surface as steam. These vents are often accompanied by a “rotten egg” smell common where sulfur is rising with the steam, turning the ground around the vents hues of yellow, green and white.

To see the new iPhone/iPod Touch App, please visit http://www.tourguidehawaii.com/iphone.html.  The best of Tour Guide Hawaii’s free content about traveling to, and exploring, the Big island, can be found here.  For more information on traveling to Hawaii in general and on touring the Big Island in particular, please also visit www.tourguidehawaii.com and www.tourguidehawaii.blogspot.com.

Copyright 2009 by Frank Burgess; photography copyright 2009 by Donald B. MacGowan. All rights reserved.

Fabulous, Fascinating, Incredible: The New iPhone And iPod App; a Perfect Tour Guide To Hawaii In The History of Forever!

THE must have iPhone / iPod Touch app for all residents and visitors to the Big Island of Hawaii.  Get the Tour Guide iPhone and iPod App here today!

For more information on Tour Guide Hawaii’s fabulous new iPhone and iPod App, please go here, here and here.

For more information on traveling to Hawaii in general, or details on how to buy the iPhone/iPod App, please go to www.tourguidehawaii.com.

Hawaii’s Amazing Lava Fossils

by Donnie MacGowan

With minor local exceptions, the rocks of the Big Island of Hawaii are made up almost entirely of eruptive volcanic effluent—lava and ash, and sediment derived from eroding and weathering lava and ash. As such, it doesn’t seem a likely place to hunt fossils. After all, the lava pours from the vents on Hawaii’s volcanoes at between 1100° and 1130° C and even the hardened crust on the top of an active flow can be as hot as 600°C. It seems like the advancing lava ought incinerate everything in its path and leave no trace of organic matter behind as fossils.

Palm Frond Fossil in Basalt From 30-Year Old Lava Flow, Kalapana, Hawaii: Photo by Donald B. MacGowan

Or would it? Sometimes things in nature don’t always act the way we expect them to.

Lava Mold of a Palm Tree in a 2000 Year Old Flow, Honaunau, Hawaii: Photo by Donald B. MacGowan

As a child, my mind, when not actually occupied with thoughts of dinosaurs, was chiefly occupied with thoughts of volcanoes or thoughts of fossils. It’s scarcely surprising, then, that I grew up to be a geologist, but when I eventually washed-up on the shores of the Big Island, I thought I’d landed in heaven—five volcanoes, two of them active! But as I explored my new home I found more and more examples of where Hawaii’s volcanoes had preserved fossils of plant and animal life.

To be sure, owing to the extreme temperatures of the lava, these fossils tend to be molds or casts, but they are abundant and fascinating. More delicate fossils are contained in ash deposits, but so far, these have been only marginally explored.

Let’s take a quick tour around the island of Hawaii and look at some of the remarkable, amazing, lava fossils of Hawaii.

Lava Tree State Monument

Lava Tree Mold at Lava Trees State Monument, Big Island, Hawaii: Photo by Donald B. MacGowan

Let’s start down in Puna District, just a few miles south of Pahoa Town. At Lava Trees State Monument fingers of lava poke vertically at the sky, remnants of a flow that that passed through a wet ohi’a tree forest in 1790. The flowing lava enveloped the wet ohi’a trees, cooling and congealing around them. As the lava flow drained away down nearby cracks, the fingers of cooling lava were left behind. The remnants of the trees were burned and rotted away, so today these stubby towers are hollow.

Towers of Lava Tree Molds at Lava Trees State Monument, Big Island, Hawaii: Photo by Donnie MacGowan

Mauna Loa Tree Molds, Hawaii Volcanoes National Park

But what happens if the lava doesn’t drain away and leave the fingers behind, but rather cools in place around the trees? An example of this can be found along the Mauna Loa Road, in the part of Hawaii Volcanoes National Park that is north of Highway 11. Here, large acacia koa trees (the same kind of trees that are currently growing around the parking area) were buried 10-30 feet deep in lava erupted by Kilauea some 700-800 years ago.

Tree Molds on Mauna Loa in 700-800 Year Old Basalt, Hawaii Volcanoes National Park, Hawaii: Photo by Donnie MacGowan

The wet trees chilled and cooled the lava as it surrounded them and thus they were insulated from the intense heat of the surrounding flow. The cooling was rapid enough to preserve the shape, even the texture of the bark, of the trees, though the trees themselves burned away.

Kalapana-Waikupanaha

But tree trunks are not the only casts and molds that are preserved in molten lava. Sometimes even quite small items, such as coconuts and fruits are preserved with incredibly finely-detailed impressions. Down in the Kalapana-Waikupanaha area of Puna, up against the eastern border of Hawaii Volcanoes National Park, the lava surface is between 30 years and 30 minutes old.

Lava Mold of a Coconut in Basalt from a Very Recent Flow Near Kalapana, Hawaii: Photo by Donald B. MacGowan

Trails leading out to both Kaimu Black Sand Beach and the Waikupanaha Ocean Entry Lava Viewing Area are literally punctuated with preserved palm fronds, pandanus fruit, coconuts and other vegetation debris. The hiker has only to keep his eyes sharp to find hundreds of examples of where the lava has preserved, sometimes in astonishing detail, the forest it flowed through.

Mold of Pandanus Fruit in Basalt from Flow Less Than 10 Years Old, Waikupanaha, Hawaii: Photo by Donnie MacGowan

Devastation Trail, Hawaii Volcanoes National Park

As I mentioned earlier, however, sometimes other volcanic processes also preserve fossils. Along Devastation Trail in Hawaii Volcanoes National Park are some well-preserved tree molds—some with the dead tree still standing in them—from hot ash and cinder erupted from the Pu’u Pua’i vent on Kilauea Iki in 1959.

Dead Tree Standing in Future Tree Mold in Ashfall from Pu'u Pua'i, Hawaii Volcanoes National Park: Photo by Donnie MacGowan

This eruption produced fire-fountains some 1900 feet tall, showering the downwind region with hot ash and cinders. Some of the pieces of volcanic material were so hot they welded together after landing, others were so cool the trees they buried didn’t burn. Many trees were completely buried or burned away, but you can still see some, standing above the level of the ground, in what will be tree molds when the trees eventually rot away. There are also numerous examples of already empty tree molds along the trail.

Small Tree Mold Along Devastation Trail, Pu'u Pua'i, Hawaii Volcanoes National Park: Photo by Donald B. MacGowan

Warrior Footprints Trail, Hawaii Volcanoes National Park

Not all the fossils, molds and casts we find in ash and cinder deposits are from plants, either. Although the Hawaiian volcanoes have a reputation as being quiet and well-behaved, rarely violent in their eruptions, such is not always the case. There are quite thick and extensive ash deposits indicating episodes of intensely violent eruption. Called “phreatomagmatic“, these eruptions get their power and violence from ground water entering the magma chamber and flashing to steam, blowing ash high into the atmosphere. Many times the ash produced in these eruptions preserves the material it covers in quite fine detail. One such case can be visited along the Ka’u Desert/Warrior Footprints trail in Hawaii Volcanoes National Park.

Mold of Human Footprint in Ash from 1790 Phreatic Eruption of Kilauea, Hawaii Volcanoes National Park: Photo by Donnie MacGowan

In 1790, a party of warriors was passing by Kilauea on their way to make war on Kamehameha the Great. 400 men, women and children were caught in a giant phreatomagmatic eruption and suffocated where they stood. Another contingent of warriors, coming upon their companions bodies, momentarily thought them merely sleeping until they realized their comrades were all dead. Molds of the footprints left by this second set of warriors are preserved in the ash along the Warrior Footprint Trail; it’s an an eerie hike to see them.

Place of Refuge, Pu’u Honua O Hounaunau

Small Bowl Carved into Surface of Basalt, Pu'u Honua O Honaunau National Historic Park, Hawaii: Photo by Donnie MacGowan

Sometimes we find things on the surface of lava flows which do not look like any kind of natural lava flow structure, but they are also not an obvious mold, cast or fossil. Some of these features are obvious human artifacts and not fossils at all. Hawaiians would spend days carving out bowl-shaped depressions into the surface of the rock—once made, they could be used for generations. In just such manner, salt pans for evaporating sea water to get salt were constructed. Larger carved depressions were for cooking. Hawaiians would build a fire in these larger depressions until the rock was quite hot. Scooping away the fire and ash, they would add water and food to cook, sometimes continuing to add hot pebbles to keep the water boiling. Although these features are ubiquitous on the Big Island, excellent examples of them can be found all the way along the beach fronting the temple complex at Pu’u Honua O Honaunau over to Two Step Beach on Honaunau Bay.

Tree Branch Fossil Preserved in Extremely Recent Lava Flow, Kaimu, Hawaii: Photo by Donald B. MacGowan

For more information on traveling to Hawaii in general and touring the Big Island in particular, please also visit www.tourguidehawaii.com and www.tourguidehawaii.blogspot.com. For information about the author, please go here.

All media copyright 2009 by Donald B. MacGowan; all rights reserved.

Volcano Watch: Volcano Stratigraphy and Hydrology–layers and groundwater.

Reprinted from: http://hvo.wr.usgs.gov/volcanowatch/2009/09_07_30.html

A Volcano’s Many Layers Determine the Richness of Hawai`i’s Groundwater Resources

Fresh water cascades from a spring on a cliff face into a pool next to the Pacific Ocean near Nahiku on the island of Maui. The water comes from rain that fell at higher elevations on Haleakala Volcano, seeped into the ground, and has traveled slowly toward the coast. (USGS photograph by Gordon Tribble from http://pubs.usgs.gov/circ/1312/c1312.pdf)

Groundwater provides most of the fresh drinking water used in Hawai`i. Thus, discoveries that increase our understanding of the groundwater stored in our shield volcanoes are of great importance to us.

In matters of water, an island’s size counts, because the ability to wring moisture from passing air masses and hold it as groundwater depends on an island’s altitude and area above sea level. Also important is an island’s volcanic history, because it determines the rocks’ porosity (ability to absorb fluids) and permeability (“flow-through-ability”), which, in turn, affect the flow and storage of groundwater.

Having grown from the sea, a volcanic island is infused with seawater. Fresh water originates as rain, fog drip, or snow, some of which percolates into the lava flows to recharge groundwater. Most groundwater filters downward to sea level within the island, where it forms a freshwater lens-shaped body that floats upon denser salt water. The fresh-water lens thickens slightly inland, but, in most places, the top of the lens stands no more than a few meters above sea level.

The fresh-water lens is dynamic: groundwater flows constantly from inland areas of recharge to be discharged at the coast. Vertical dikes in rift zones tend to retard the lateral flow of groundwater and may impound (confine and store) it at high altitudes. Buried soil layers and ashy beds with low permeability impede the downward migration of water. They cause—above the fresh-water lens—the formation of small, perched aquifers, bodies of rock permeable enough to conduct groundwater. These dike-impounded and perched aquifers feed scattered springs found far above sea level on some islands.

Recent discoveries have added to this picture. In the 1990s, USGS hydrologists working in East Maui discovered that numerous perched aquifers in regions of abundant rainfall may be stacked until even the more permeable, intervening layers become saturated with groundwater. The result is a much thicker lens of fresh water, with an upper surface higher than the typical few meters of the conventional model.

At about the same time, researchers at the University of Hawai`i made a startling discovery about the role that soil and ash beds play in guarding the groundwater in the lava flows of Mauna Kea. Their findings resulted from chemical analyses of water in lava flows intercepted by drilling of the hole for the Hawai`i Scientific Drilling Project near Hilo Airport.

As the weight of the island bowed the underlying oceanic crust downward, these low-permeability soil and ash layers, now deep below sea level, prevented fresh and salt water from mixing. Thus, fresh groundwater fed by rainfall in lava-flow aquifers upslope persists well below sea level at the island’s edge. The layering of beds in the Hilo drill hole is like a sandwich of alternating fresh- and salt-water-bearing lava flows, each separated by low-permeability layers. Fresh water in the deep layers seeps unseen into the ocean at depths of 300 m (1,000 ft) or more.

Discoveries don’t end with Maui and Hawai`i, however. USGS hydrologists working in the Lihu`e basin of Kaua`i have found that low-permeability layers impounded a groundwater system that stands at least 100 m (300 ft) above sea level and more than that below sea level. The low-permeability layers were formed during late-stage volcanism, long after most of the island had been built. On Kaua`i, this volcanic stage, known as the rejuvenated stage, has produced rocks with characteristics that differ from those of more typical shield-building lava-flow aquifers. Natural seepage from the thick freshwater lens plays an important part in maintaining the flow of perennial streams in the basin.

The same low permeability that results in the formation of thicker freshwater lenses on Kaua`i and Maui and causes deeper fresh water to leak offshore from Hilo, however, also limits the rate at which groundwater can be extracted. Overpumping allows underlying brackish water to intrude and diminishes the flow to springs and streams. As with all natural resources, we need to manage our use of groundwater in a sustainable way. Recent and ongoing studies of Hawai`i’s geology and hydrology will enable us to do that more effectively.

Kīlauea Activity Update

Surface flows continued to be active on the pali in Royal Gardens subdivision. At the coast, the Waikupanaha ocean entry remains active, but the Kupapa`u ocean entry is no longer active. A deflation-inflation cycle (or DI event) started at the summit on Thursday, July 30 (the date of this writing). DI events often disrupt the lava supply to the east rift zone for several days.

The vent at Kīlauea’s summit was dark and quiet all week, producing only a very small quantity of rock dust from small collapses of the vent walls. Volcanic gas emissions have increased over the past two weeks and are currently similar to levels prior to June 30, resulting in high concentrations of sulfur dioxide downwind.

No earthquakes beneath Hawai`i Island were reported felt this past week.

Best Scenic Drives on Hawaii #1: The Saddle Road…Kona to the Summit of Mauna Kea, Kaumana Cave and Hilo

Across the Roof of Hawaii

by Donnie MacGowan

This post has been updated and expanded here.

Recent improvements to the Saddle Road make it no longer the grinding, intimidating drive it once was and open hundreds of square miles of unimaginably beautiful, strange and wondrous landscape to the Hawaii Island Visitor.

Approximate minimum time start to finish (to see every site): 12 hours

From Kona take Highway 190 to Highway 200 in 45 minutes of driving. Saddle Road, which cuts between the “saddle” of Mauna Loa on the south and Mauna Kea to the north, passes through ranch lands and the Pohakuloa Military Training Facility, for another 45 minutes, to the turn for Mauna Kea Access Road (John Burns Way). Nearby, Kipuka Huluhulu, or “shaggy hill”, is a 20 minute hike to the top and back. From here it is a 30 minute drive to the Mauna Kea Visitor Information Center. The small village is home to scientists and astronomers that work in the observatories and an amazing place to learn what their research tells us about our universe. Returning to Hwy 200, drive 45 minutes to the amazing Kaumana Cave lava tube, a short hike and a wonderful exploration. A further 30 minutes down Hwy 200 brings one to downtown Hilo, where there are shops, restaurants, fine museums, gorgeous waterfront beach parks and a fabulous Farmers Market. From Hilo, it is approximately three hours to return to Kailua Kona over Hwy 200; alternately one can take the faster though less scenic Hwy 19 to Waimea and then Hwy 190 into Kailua Kona, about a 2 1/2 hour drive.

Ahu'ena Heiau, Kailua Kona Hawaii: Photo by Donnie MacGowan

Leg 1) In Kailua Kona, start at Ahu’ena Heiau; take Palani Road east to Hwy 190; take Hwy 190 to jct with Hwy 200, The Saddle Road

Ahu’ena Heiau and Kamakahonu Beach

Centuries ago the inhabitants of this region built a series of sacred temples, or heiau, which were originally used for the purpose of sacrificing human beings to their war god, Kuka’ilimoku. This particular archeological site is called Ahu’ena Heiau, which in Hawaiian means “Hill of Fire”.

Built originally in the 15th century and rededicated by Kamehameha the Great in the early 1800s as the main temple of his capital, the current structures seen at Ahu’ena Heiau were re-built in 1975 under the auspices of the Bishop Museum with financial help from the Hotel King Kamehameha and are constructed to 1/3 the original scale. There are restrooms and showers located on the pier near the beach. Adjacent Old Kailua Town is a treasure of shops, restaurants and aloha.

Hualalai Volcano from Saddle Road, Big Island Hawaii: Photo by Donnie MacGowan

Leg 2) Take Hwy 200, The Saddle Road, east to jct with John Burns Way (also called Mauna Kea Access Road).

Looking West from Highway 190 to Hualalai Volcano Halfway between Kona and Waimea, Big Island of Hawaii: Photo by Donald B. MacGowan

Saddle Road

Crossing the spectacular saddle between the towering bulk of the volcanoes Mauna Kea and Mauna Loa at about 6600 feet, The Saddle Road runs through brush, grass and forest lands, over lava fields and through some of the wildest and most breath-taking scenery on the Island. From this roadway, four of the 5 principal volcanoes that form The Big Island may be seen: Hualalai, Kohala, Mauna Loa, and Mauna Kea. Because the western half of the road is in notoriously poor condition and consists, in reality, of only one operable lane for much of its descent from the saddle to the Mamalahoa Highway.

However, this road provides the only road access to the Mauna Kea Summit Area and Visitor Information Center, Mauna Kea State Park, Pohakuloa Training Area, Mauna Kea Astronomical Observatory Complex, Waiki’i Ranch and the Kilohana Girl Scout Camp. The Saddle Road also provides the only access to thousands of acres of public forest and open grass lands. Connecting Hilo from about milepost 7.8 on the Hawai’i Belt Road to the Mamalahoa Highway approximately 6 miles south of Waimea, the Saddle Road is widely used by island residents for cross-island travel, despite its somewhat poor condition and undeserved, evil reputation.

Mauna Kea From Mauna Kea State Park; Note V-Shaped Stream Valleys and Glacial Cirques: Photo by Donald B. MacGowan

The Saddle Road frequently has perfect weather, but also fairly routine are patches of intense rain, fog and high winds. It’s takes about 2 ½ to 3 hours straight driving time, depending upon weather, to make the full traverse from Kailua Kona to Hilo; however, one should be sure to leave time in the schedule to drive up to Mauna Kea Visitor Information Station or hike the Pu’u Huluhulu nature trails.

Along its entire 53 mile length between the turn-off from the highway just 6 miles west of Waimea and where it meets Hawaii Belt Road just north of Hilo, there is no gas and there are no services available; plan accordingly. Some food, water and restrooms may be available at the Mauna Kea Visitor Information Station which is a 30 minute drive up a side road off the Saddle Road about half way.

Kipuka Huluhulu from Saddle Road: Photo by Donald MacGowan

Leg 3) Off a Spur road at the jct of John Burns Way and Hwy 200, on the south side, is Kipuka Huluhulu (“Shaggy Hill”) Nene Sanctuary.

Pu’u Huluhulu Nature Trails/Kipuka Aina Hou

Frequently described as simultaneously the most noticeable and the most overlooked landmark along the Saddle Road, Kipuka Pu’u Huluhulu rises more than 200 feet out of the surrounding lava flows. It’s name meaning “furry hill”, this forested cinder cone has multiple trails winding up through rare native koa trees to breathtaking 360° views of Hualalai, Mauna Kea and Mauna Loa at the top, where you can also wander a meadow of native Hawaiian plants recently reintroduced in this protected natural habitat. By whatever trail, the summit of Kipuka Huluhulu is only about 20 minutes walk from the car.

Owing to the encapsulated nature of the kipuka, bird watching here is particularly fabulous; the Ā’akepa, Nene and the Ā’akiapola Ā’au, as well as the Kalij pheasants, pueo, i’o and turkeys are among the rare, endangered or just plain beautiful birds you will see here. The numerous roads and trails through the hundreds of square miles of adjacent lava flows makes for interesting, if hot and dry, mountain biking and hiking.

Parking and a unisex pit toilet are the only amenities available at Kipuka Pu’u Huluhulu.

Mauna Kea From Kipuka Huluhulu Nene Sanctuary: Photo by Donald MacGowan

Looking South from Mauna Loa to Mauna Kea from Near Lake Wai'au: Photo by Donnie MacGowan

Leg 4) Go north on John Burns Way to Mauna Kea Visitor Information Station.

Mauna Kea Visitor Information Station

The Visitor Information Station is open daily from 8 a.m. to 5 p.m. During the day there are interactive computer exhibits about Mauna Kea, the observatories and astronomical research, plus there are video presentations and nature trails to hike. Many evenings after dark National Park personnel and astronomers put on public programs and discuss what the latest astronomical findings tell us about the nature of our universe. The souvenir shop has some food items, including hot chocolate, coffee and hot soup, for sale.

Hikers on Mauna Kea Summit Looking at Mauna Loa Summit: Photo by Donnie MacGowan

Leg 5) John Burns Way to Mauna Kea Summit

Mauna Kea Summit

Before you decide to go to the summit of Mauna Kea, stop, think, plan. Are you prepared for cold and high altitude? Do you understand the nature and dangers of altitude sickness and UV radiation? Are you experienced at traveling icy dirt roads? Is you car safe for the trip (many car rental agencies on the island forbid you to drive this road)? The Rangers at the Visitor’s center can brief you on altitude sickness, UV radiation preparedness, the condition of the road and all other information you need to decide whether to visit the summit (see a video here).

Lake Wai'au--the Seventh Highest Lake in the US--Whose Name Means "Swirling Water", Perches Near the Summit of Mauna Kea On The Big Island of Hawaii: Photo by Donnie MacGowan

The summit of Mauna Kea is truly an amazing place. Beautiful, awe-inspiring, 360 degree views of the entire Big Island, the summit is also culturally and religiously important to the native Hawai’ians and is home to several, world-class astronomical observatories and their support buildings. Because of the extremity of the altitude and the poor quality of the road above the Visitor’s Center, it is advised that extreme caution be exercised in deciding to visit Mauna Kea’s Summit. From the road’s end very near the summit, a short, 10 minute trail leads up Pu’u Weiku cinder cone to the actual mountain top and a Hawaiian religious shrine. Also near the summit is the 1-mile hike to Lake Waiau, the 7th highest lake in the US, as well as numerous archeological sites. Moving at altitude is strenuous, so conserve energy. Do not over-tax yourself, be sure to drink plenty of fluids and protect yourself from the sun, wind and cold. Leave the summit area and return to the paved road long before you are tired.

Kaumana Cave, Hilo Hawaii: Photo by Donnie MacGowan

Leg 6) Return John Burns Way to Hwy 200; take Hwy 200 east to Kaumana Caves

Kaumana Caves

A skylight opening to 25-mile long Kaumana Cave is located at the county park near the 4-mile marker on the Hilo side of the Saddle Road. Concrete stairs take you down through the rain forest jungle to the bottom of a collapse pit forming two entrances to the cave. Most people are drawn to the entrance on the right, a large, opening leading to cavernous rooms. In this entrance, graffiti from hundreds of years ago to the present is preserved, scratched into the rocks. The entrance on the left, however, is more interesting, leading through squeezes and low spots to numerous rooms with fascinating speleo-architecture and cave formations. Both caves go to true dark in fewer than 300 feet in either direction. There are more than 2 miles of easily accessible, wild cave to explore here, but if you intend more than just a cursory inspection near the entrances, bring a hard hat, water and at least 3 sources of light. A quick tour of the caves takes fewer than 20 minutes.

Kaumana Cave's Skylight Entrance: Photo by Donnie MacGowan

Parking for the caves is located across the highway from the park; extreme care should be taken when crossing he road. Public restrooms, water and picnic tables are available at the park. As you approach Hilo from Kaumana Caves, Hwy 200 becomes variously called Kaumana Drive, then Waianuenue Avenue.

Astronomical Observatories on the Summit of Mauna Kea, From Downtown Hilo: Photo by Donnie MacGowan

Leg 7) Take Hwy 200 into Hilo Town.

Hilo Town

Beautiful but wet, metropolitan but decrepit, bustling but laid back, Hilo is a lovely, maddening, heartbreaking, addictive study in contrasts. In can rain all day long for 50 days in a row, yet when the sun does shine, the views of Mauna Loa and Mauna Kea from the Liliuokalani Gardens, or of Hilo Bay as you drive down from the mountains, or the rain-forest and waterfall choked gulches with lovely beaches along the highway north of town, make Hilo one of the most truly, achingly-lovely spots on earth.

Hilo's Charming Bayfront Shops: Photo by Donald MacGowan

More laid back and sleepier than bustling Kailua Kona, Hilo is the largest town on the island, and the county seat. The Imiloa Astronomy Center of Hawaii, Tsunami Museum, Lyman House Missionary Museum and the Panaewa Rainforest Zoo are all wonderful places to learn about various aspects of Hawaii. There are numerous shopping districts, two large malls and the Historic Old Hilo downtown shops to browse through, a variety of sprawling green parks, a fabulous tropical arboretum right downtown and a mile-long black-sand beach fronting the bay to explore. Hilo’s Farmer’s Market is a “must see” for any visitor who is spending time on this side of the island.

Mauna Kea's Summit from Highway 19 Near Waimea Town: Photo by Donald MacGowan

Leg 8) Return Waianuenue Avenue to Kaumana Drive to Hwy 200; take Hwy 200 west to jct with Hwy 190; take Hwy 190 west to Kailua Kona.

Trogdor at Keauhou Bay, Kona Hawaii: Photo by Donnie MacGowan

For more information on traveling to Hawaii in general and touring the Big Island in particular, please visit www.tourguidehawaii.com and www.tourguidehawaii.blogspot.com. Information about the author is available here.

All media copyright 2009 by Donald B. MacGowan

Volcano Update: 2009—A year of noteworthy volcano anniversaries in Hawai`i

Reprinted from here.

2009—A year of noteworthy volcano anniversaries in Hawai`i

Thomas Jaggar (second from left) prepares to measure the temperature of the Halema`uma`u lava lake in 1917. Pictured, left to right, Norton Twigg-Smith, Thomas Jaggar, Lorrin Thurston, Joe Monez, and Alex Lancaster.

Thomas A. Jaggar, founder of the Hawaiian Volcano Observatory (HVO), first visited Hawai`i 100 years ago during a decade-long period of exploration in which he witnessed first-hand the destructive power of volcanic processes.

His quest began in 1902, when Jaggar traveled to the West Indies just 13 days after two volcanoes there erupted with devastating consequences. The first eruption at La Soufriere on the island of Saint Vincent resulted in 1,500 deaths. It was followed only a few hours later by a second, more tragic, eruption at Mount Pelee on Martinique, in which 28,000 people perished. Jaggar’s experience at Martinique set the stage for his work on volcanoes and earthquakes during the next half century.

After Martinique, Jaggar’s expeditions took him to the scenes of earthquakes and volcanic eruptions in the Aleutians, Central America, and Japan. In 1908, an earthquake near Mount Etna in Italy killed 125,000 people. Following that natural disaster, Jaggar declared that “something must be done” to support systematic studies of volcanic and seismic activity.

The next year, in 1909, he traveled at his own expense to Hawai`i, where he determined that Kīlauea was to be the home of the first American volcano observatory. His vision was to “protect life and property on the basis of sound scientific achievement.”

In 1912, construction began on the new Hawaiian Volcano Observatory with support from Hawai`i businesses, private endowments through the Hawaiian Volcano Research Association, and funding from the Massachusetts Institute of Technology. HVO has since been managed by the U.S. Weather Bureau (1919-1924), U.S. Geological Survey (1924-1935), and National Park Service (1935-1947). The USGS became the permanent administrator of HVO in 1947.

In 2012, HVO will celebrate its centennial anniversary, a milestone made possible through the vision and efforts of Thomas A. Jaggar.

Today, in 2009, as we look back at Jaggar’s first visit to Kīlauea 100 years ago, we also reflect on the landmark anniversaries of several significant eruptions on Kīlauea and Mauna Loa:

25^th — 1984 Mauna Loa summit and northeast rift zone eruption
40^th — start of the 1969-74 Kīlauea east rift zone eruption (Mauna Ulu)
50^th — 1959 Kīlauea summit eruption (Kīlauea Iki)
60^th — 1949 Mauna Loa summit eruption
90^th — 1919 Mauna Loa southwest rift zone eruption
150^th — 1859 Mauna Loa northwest flank eruption

Give new life to your old photographs of Hawai`i’s volcanoes!

Reprinted from here.

A view of the lava lake within Halema`uma`u Crater on December 27, 1911, with Uwekahuna bluff (where HVO and the Jaggar Museum now stand) and Mauna Loa in the background. The lake level had risen about 120 m (400 ft) since October 1911 and will drop 90 m (300 ft) in January, 1912, the month that HVO was founded by Thomas A. Jaggar's arrival for duty.

The adage “a picture is worth a thousand words” is certainly true, especially when it comes to photographs of Hawaiian eruptions and volcanic landscapes from earlier times.

Long-time readers of “Volcano Watch” might recall our January 20, 2005, article (http://hvo.wr.usgs.gov/volcanowatch/2005/05_01_20.html), which describes an HVO geologist’s excitement at finding an 1860s photo of Kilauea’s caldera. By comparing the photo to a present-day view of the caldera, he could see the location of volcanic features described in written records (with less than a thousand words) but no longer visible today—a valuable discovery when your job is to decipher a volcano’s eruptive history.

Without realizing it, you or a family member may have captured a similarly important historical record of Hawai`i’s volcanoes. How? By taking a photo and keeping it.

Your `ohana, like many families, probably has several albums—or shoe boxes—filled with old photographs. Perhaps your great-grandmother took a picture of a long-ago Kilauea summit eruption or your brother snapped a photo of `a`a lava as it flowed down the slopes of Mauna Loa. If you possess photographs that show volcanic landscapes or features, volcanic fume (vog), or any kind of eruptive activity, HVO geologists would like to hear from you and see the photos.

We learn the most from photographs that have some documentation about when and where they were taken. Date and location are essential pieces of information that help us interpret the geologic significance of a photo. If people are recognizable in a photograph, their names should also be included. Any other details you can provide about the image will add to its meaning.

Wide-angle shots are more helpful than close-ups. For example, if a photo is zoomed in on the leading edge of a lava flow and shows nothing else, we cannot determine the size of the flow-or much of anything else—from the image. With wide-angle views, we can see the geographic or geologic context of the eruptive activity or volcanic features shown in the photograph.

If you’re interested in sharing your photos with HVO scientists, the first thing you should do is contact us by telephone (808-967-7328) or email us (askHVO@usgs.gov). Geologists are standing by to speak with you. The purpose of this initial conversation is to determine which of your photographs might be beneficial to our research and monitoring efforts on Hawai`i’s volcanoes. We will then send you additional information on how we can receive and duplicate photos selected from your collection.

No need to worry about giving up your photographs—you retain ownership of them. We will return your photos to you after duplicating the images selected as most useful. In appreciation of your loaning us the photographs, we will be happy to give you digital copies of the images we scan.

To kick off our effort to expand HVO’s photographic collection of Hawai`i’s volcanoes, we are asking at this time to see photographs from 1924 and earlier. Those years included frequent lava lake activity in Halema`uma`u Crater and culminated in the explosive eruptions of May 1924.

Pre-1924 photos are of particular interest to us now because they could shed light on Kilauea’s current summit eruption. Even if they show no eruptive activity, early photographs of Kilauea’s caldera can contribute to a better understanding of the volcano’s past and reveal features that are no longer visible. The same is true for early photos of Mauna Loa and Hualalai.

We will initially focus on early historical photographs, but you can contact us about any volcanic images you think might interest us. Although we may not be able to look at photos taken in recent decades right away, we would eventually like to see them. Our ultimate goal is to acquire images from the 1800s through the 20th century.

So, please lend us a hand while taking a trip down memory lane. Look through your family photos and contact HVO if you find images of Hawai`i’s volcanoes. Your old photographs could give new life to eruptive events and volcanic landscapes rapidly fading from our visual memories.

Kīlauea Activity Update

Surface flows in the Royal Gardens subdivision remained active as of Thursday, June 18, burning through forested kipuka. Another area of breakouts active higher up on the pali was also reported. The Waikupanaha and Kupapa`u ocean entries remain active and continue to produce prominent plumes as lava spills into the ocean.

At Kīlauea’s summit, the vent within Halema`uma`u Crater continues to emit elevated amounts of volcanic gas, resulting in high concentrations of sulfur dioxide downwind. Bright glow from the vent was visible at night through the past week. A collaborative effort last week between HVO and UH-Manoa scientists, using a sophisticated optical remote-sensing technology called LIDAR (Light Detection and Ranging), has measured the lava surface to be about 205 m (675 feet) below the floor of Halema`uma`u Crater.

No earthquakes beneath Hawai`i Island were reported felt this past week.

For more information on traveling to Hawaii in general and exploring the Big Island’s volcanoes in particular, please also visit www.tourguidehawaii.com and www.tourguidehawaii.blogspot.com.

Volcano Update: New Webcam menu makes lava views safely available

Reprinted from here.

New Webcam menu makes lava views safely available

Lava in Kīlauea’s summit vent creates a nighttime glow that can be safely observed from the Jaggar Museum overlook in Hawai’i Volcanoes National Park or on the HVO Webcam. Inset image shows the lava surface, which was moving from top center to lower left at the time it was taken.

The HVO Web site was recently revamped to make access to our increasing number of Webcams easier for viewers and the HVO staff who post Webcam images. All HVO Webcams are now linked through a single menu at http://hvo.wr.usgs.gov/cams/.

The menu lists our five Webcams showing Moku`aweoweo, Mauna Loa summit caldera, the TEB vent and lava tube system on Kīlauea’s east rift zone, Pu`u `Ō `ō crater, and two views of the Halema`uma`u vent—one from HVO and another from the rim of Halema`uma`u crater immediately above the new vent.

Webcams allow us to make critical measurements with relatively little risk. The Webcams can work in rain, wind, very high concentrations of sulfur dioxide, and even moderate amounts of ash blasted from the vent. They can be in areas where access is restricted for safety reasons. Webcams can be where people should not.

Two of our Webcams have shown active lava in recent days. On Tuesday night, the TEB Webcam caught active flows near the top of the abandoned Royal Gardens subdivision. As an added treat, the Webcam also caught lights from a cruise ship passing the Kalapana shoreline in the late evening getting good views of the active flows and the Waikupanaha ocean entry.

The Webcams that chronicle developments below the floor of Halema`uma`u Crater have recorded lots of glow since early May. In fact, the recent glow has been the brightest since October 2008. The brightness of the glow is due to molten lava circulating in a narrow conduit about 100 m below the crater floor and about 180 m below the crater rim.

The Webcam located on the rim of Halema`uma`u was recently repositioned to look directly into the vent for views of the circulating lava when clear enough. The wispiness of the gas plume and the relative shallowness of the molten lava have allowed some good views recently. The vent is masked by sunlit fume during the day and is overexposed at night so the best times to look at Webcam views of lava are at dusk and dawn.

The unwavering Webcam views will allow us to better monitor the rise and fall of the lava within the vent. HVO geologists have also recorded video of the lava surface that shows some fascinating movements (http://hvo.wr.usgs.gov/kilauea/update/images.html). The lava emerges from the right side of the Webcam view and flows left across the opening. The flowing lava surface looks chaotic with lots of splashing and bursting bubbles—activity that produces the tephra that is carried aloft by the hot, rising gas and deposited on the rim.

Two recent Volcano Watches have discussed reasons for lava circulation using a lava lamp analogy. Magma must be convecting with the conduit, like the “goo” in a lava lamp, bringing hot, bubble-rich lava to the surface while allowing cooler, bubble-poor lava to sink.

Looking at lava within the Halema`uma`u vent conduit is like watching a lava lamp from above through a hole in the top, all the goo colored orange, and blobs being gas bubbles that burst when they get to the top.

Views from the Halema`uma`u Webcam should allow us to test our ideas about what precedes brown plumes and explosive eruptions. Do rocks fall from vent walls into the molten circulating lava trigger a vigorous gas release which could carry even more spatter and rock dust out of the vent. Or are the brown plumes and more energetic explosive eruptions initiated by a big slug of gas coming up the conduit.

For safety reasons, Hawai`i Volcanoes National Park restricts access to the entire caldera including Crater Rim Drive from Jaggar Museum south to the Chain of Craters Road intersection. Thanks to the HVO Webcams, we can all see what’s happening from much safer vantage points.

Kīlauea Activity Update

A deflation/inflation (DI) event at the summit of Kīlauea last weekend disrupted the supply of lava through the tube system and caused the Waikupanaha and Kupapa`u ocean entries to shut down. Both entries had resumed by mid-week, accompanied by breakouts near the top of Royal Gardens subdivision and just inland from Kupapa`u.

At Kīlauea’s summit, the vent within Halema`uma`u Crater continues to emit elevated amounts of sulfur dioxide gas, resulting in high concentrations of sulfur dioxide downwind. Vigorously upwelling lava within the vent below the crater floor produced bright glow at night, loud gas-rushing noises, and the emission of juvenile ash during the past week.

One earthquake beneath Hawai`i Island was reported felt this past week. A magnitude-3.4 earthquake occurred at 3:55 p.m., H.s.t, on Saturday, May 30, 2009, and was located 9 km (6 miles) southwest of Kīlauea Summit at a depth of 26 km (16 miles).

Visit our Web site (http://hvo.wr.usgs.gov) for detailed Kīlauea and Mauna Loa activity updates, recent volcano photos, recent earthquakes, and more; call (808) 967-8862 for a Kīlauea activity summary; email questions to askHVO@usgs.gov. Volcano Watch is a weekly article and activity update written by scientists at the U.S. Geological Survey’s Hawaiian Volcano Observatory.

For more information on traveling to Hawaii in general and touring the volcanoes of the Big Island in particular, please also visit www.tourguidehawaii.com and www.tourguidehawaii.blogspot.com.

Volcano Update: Magma within Kīlauea’s summit vent never goes flat

Reprinted from here.

Magma within Kīlauea’s summit vent never goes flat

On May 14, a brief bit of clear weather shows the Halema`uma`u plume rising and blowing with the wind.

Two weeks ago, readers of this column learned about the genesis of brown plumes and sudden gas release from Kīlauea’s summit vent. This week we will continue that exploration, looking farther into Kīlauea’s magma plumbing system to explain why the summit vent has become a long-lived feature of the volcano.

As residents of the Big Island can attest, vog has been a substantial irritant since the formation of Kīlauea’s summit eruptive vent in early 2008. Can we expect this release of volcanic gas to go away anytime soon? The short answer is no, but that requires a bit of explanation.

As magma rises to shallow levels beneath the ground surface, pressure on the magma drops, and gas is released—similar to opening a can of soda (dropping pressure), allowing the dissolved carbon dioxide to bubble out. The magma will go flat once all of the gas is released, suggesting that Kīlauea’s summit should eventually stop releasing gas.

The persistence of volcanic gas emissions from Kīlauea’s summit is evidence that the supply of gas-rich magma is being replenished. To understand why, we’ll need to understand the principle of convection—in other words, how a lava lamp works.

In a lava lamp, heat added at the bottom warms the colored blobs within the lamp, causing them to become less dense and rise to the top. Since the top of the lamp is away from the heat source, the colored blobs gradually cool, become denser, and sink. The cycle repeats itself until the lamp is turned off.

A similar process is probably occurring beneath Kīlauea’s summit but is driven by gas release instead of by heat. Magma within the summit vent is like an open soda, where dissolved gases gradually come out of solution. As the magma goes flat, its density increases. Eventually, the dense, flat magma will sink and be replaced by less-dense, gas-rich magma—a lava lamp in action! As a result of this process, the summit plume of gas and ash is constantly renewed.

Besides the unusual persistence of the summit plume, there is other evidence that convection is occurring within Kīlauea’s shallow magma system.

If you read the Kīlauea daily activity updates, posted on the Hawaiian Volcano Observatory (HVO) Website each morning, or are a regular reader of this column, you’ve probably heard of “DI” events. “DI” is shorthand for “deflation-inflation.” These events occur as the summit suddenly begins to deflate and then, after about 12–48 hours, just as suddenly begins to inflate and returns to normal.

Prior to 2008, the average number of DI events occurring in any given year was about 10. In 2008, however, there were 47 DI events and, in 2009, there have already been 15 thus far.

DI events may be a physical manifestation of convection within Kīlauea’s shallow magma plumbing system. DI deflation could be caused by downward flow of dense, “flat” magma, with DI inflation representing the rise of fresh, gas-rich magma. During the time between DI events, fresh magma would gradually degas and become denser. The increase in the frequency of DI events in 2008 probably reflects the fact that, due to the start of the summit eruption, the magma rose to very shallow depths, allowing for much more efficient and rapid degassing.

Vent collapses, like the one that generated the spectacular brown plume in early May, are sometimes associated with DI events. Assuming that DI deflation signifies the downward flow of dense magma, collapses might be expected, due to removal of magmatic support from the eruptive vent.

Although magma convection is suspected at several volcanoes worldwide, the process is difficult to document, because there is no way to see directly into a magma chamber. At Kīlauea, however, the outstanding level of geophysical and geochemical monitoring has provides good evidence of convection just beneath the volcano’s surface.

Scientists at HVO will continue to study DI events, gas emissions, brown plumes, and other signals from the summit vent in hopes of learning more about Kīlauea’s magma plumbing system. There is no doubt that this lava lamp will be going for a long time to come, so stay tuned to this column and the daily activity updates for the latest information!

Kīlauea Activity Update

The Waikupanaha and Kupapa`u ocean entries remain active and are topped by robust laze plumes. Frequent small collapses have prevented either entry from building a large delta. There have been no lava breakouts from anywhere along the tube system reported in the last week.

At Kīlauea’s summit, the vent within Halema`uma`u Crater continues to emit elevated amounts of sulfur dioxide gas, resulting in high concentrations of sulfur dioxide downwind. Glow, gas-rushing noises, and the emission of juvenile ash during the past week suggest that a small lava lake is still present below the floor of Halema`uma`u Crater.

No earthquakes beneath Hawai`i Island were reported felt this past week.

Visit our Web site (http://hvo.wr.usgs.gov) for detailed Kīlauea and Mauna Loa activity updates, recent volcano photos, recent earthquakes, and more; call (808) 967-8862 for a Kīlauea activity summary; email questions to askHVO@usgs.gov. Volcano Watch is a weekly article and activity update written by scientists at the U.S. Geological Survey’s Hawaiian Volcano Observatory.

For more information about traveling to Hawaii in general and touring the Big Island in particular, please also visit www.tourguidehawaii.com and www.tourguidehawaii.blogspot.com.