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by Donald B. MacGowan

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Hikers pause to look over the summit from Mauna Loa from the summit of Mauna Kea, Hawaii Graphic From Photo by Donald B MacGowan

There are many wondrous, enigmatic and fascinating attractions on the Big Island of Hawaii, some better known than others, many out of the way and generally off the beaten track. Tour Guide Hawaii has produced an encyclopedic collection of the most up-to-date information, presented as short GPS-cued videos, in an app downloadable to iPhone and iPod Touch that covers the entire Big Island, highlighting the popular and the uncrowded, the famous and the secluded, the adventurous and the relaxing.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

A view from the summit of Hualalai to Mauna Loa Hawaii Photo by Donald B MacGowan

The Volcanoes of Hawaii Island

The Hawaiian Archipelago, part of the Hawaiian Island-Emperor Seamount chain, is the most isolated island group earth and is comprised entirely of volcanic islands and their fringing reefs.  The archipelago was formed as one of the Earth’s great tectonic plates, the Pacific Plate, moved steadily northwest over a stationary plume of molten material welling up from the Earth’s mantle, called a “hot spot”.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Fumes bellow from skylights in an active lava tube on Kilauea Volcano, Hawaii Photo by Kelly Kuchman

Creating a chain of volcanic islands that, today, stretches from the Aleutian Islands to the Big Island of Hawaii, this hotspot gave rise to at least 129 separate volcanoes in the past 86 million years.  There are 19 islands and atolls, and dozens of separate islets, seamounts, reefs and shoals in the Hawaiian Island portion of this chain, stretching from Kure Atoll to Hawaii Island (please go here for a complete discussion of the geologic history of the Hawaiian Islands).

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Halema'uma'u Crater and Eruption on Kilauea, Hawaii Photo by Donnie MacGowan

Hawai’i is the youngest island in the Archipelago and first began forming about a million years ago as volcanic vents opened above the mantle “hot spot” on the ocean bottom and molten lava began pouring onto the sea floor. Over the centuries, the making of the Big Island as we know it today eventually entailed the growth and conjoining of six separate volcanoes, building all the way up from the seafloor, some 18,000 feet below the ocean’s surface.  These volcanoes, from northwest to southeast, are named Mahukona, Kohala, Mauna Kea, Hualalai, Mauna Loa and Kilauea, and become younger as one moves north to south.

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Lava Flowing Into the Sea at Waikupanaha, Hawaii Photo by Donald B MacGowan

Mahukona Volcano, just off the Big Island’s northwest coast, was the first volcano to start forming. Now submerged beneath the surface of the ocean because it is sinking into the Earth’s crust under its own vast weight, Mahukona is no longer visible.  As the Pacific Plate slowly continued moving northwestward over the hotspot, the location of the rising magma moved relatively southeastward, and through time the rest of the Big Island volcanoes formed along that path.

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Kohala Mountain from the slopes of Mauna Kea Photo by Donald B MacGowan

After Mahukona, Kohala Volcano, the precursor to today’s Kohala Mountain, erupted next.  As Kohala Volcano emerged from the sea and joined with Mahukona, a much larger Big Island began forming. With continued movement of the Pacific Plate, the center of volcanism migrated on to Mauna Kea and Hualalai, the middle-aged volcanoes, and finally on to Mauna Loa and Kilauea, which are the youngest volcanoes on the island.  Over the geologically short time of several hundred thousand years, these volcanoes erupted thousands of thin flows which spread over, and built upon, older flows; each volcano growing until it finally emerged from the sea. As time went on, lava flows from one volcano began to overlap flows from other, nearby volcanoes and eventually the peaks coalesced into a single island, the Big Island.

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Lava from Kilauea flows into the sea at La'epuki, Hawaii Photo by Donald B MacGowan

In geologically recent times, a new volcano, Lo’ihi, began forming about 18 miles off the southeast coast of the Big Island.  In time, Loihi may join its mass with that of Kilauea, again changing the size and shape of the Big Island.  It is estimated that Lo’ihi, whose summit lies approximately 3,178 feet below the surface of the ocean today, will begin to protrude above the surface in about 10,000 years.

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Hualalai Volcano from Saddle Road, Hawaii Photo by Donald B MacGowan

Currently, the remnants of Mahukona and Kohala volcanoes are completely extinct; Hualalai and Mauna Kea are considered dormant and Mauna Loa, Kilauea and Loihi are still very active.   This means that eruptions of Mahukona and Kohala are not at all likely. Eruptions of Mauna Kea and Hualalai are probable at some time in the future, though the major phase of mountain building is over for these volcanoes.  Movement of the Pacific Plate has moved both Hualalai and Mauna Kea off the hot spot so only remnants of liquid magma reside beneath them. These late-stage, mature Hawaiian volcanoes experience violent, explosive eruptions which are spectacular but comparatively small, volume-wise.  Late-stage Hawaiian volcanic eruptions are characterized by crater-forming explosions, tephra-cone building and ash ejecting events.

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Mauna Loa from Bird Park in Hawaii Volcanoes National Park: Photo by Donald B MacGowan

Mauna Loa and Kilauea are both considered active volcanoes. Although inflation and dilation events are common on the summit of Mauna Loa, it has not erupted since 1984; Mauna Loa could, however, erupt at any time.  Since 1833 when accurate records began to be kept, there have been 33 eruptions of Mauna Loa, making it one of the most active volcanoes on earth.  Its name means “long mountain”, and Mauna Loa is capable of erupting huge amounts of lava in a very short time, dwarfing the current output of Kilauea.  The most massive mountain on earth, this prolific effusion of molten rock accounts for Mauna Loa’s vast bulk.

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Kilauea eruption in Halema'uma'u Crater at night, Hawaii Volcanoes National Park: Photo by Donald B MacGowan

Kilauea, once believed to be a mere satellite vent on Mauna Loa, is known to be a separate and distinct volcano with its own, geologically separate magma chamber and subterranean plumbing. Nearly half a million years old, Kilauea’s most recent eruption has been continuous since 1983 making it currently the world’s most active volcano. Indeed, between 1983 and 2009 about 700 acres of new land were produced by lava flows from Kilauea.  Articles on how to see the active lava flows on Kilauea can be found here and here. A detailed guide to enjoying Hawaii Volcanoes National Park, featuring Kilauea and Mauna Loa Volcanoes can be found here.

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Kilauea buried the town of Kalapana in the early 1990s and formed Kaimu Black, Hawaii: Photo by Donald B MacGowan

Because the time-scale of human experience is virtually instantaneous compared to the aeons-long march of geologic history, there is continuing human drama, a tension, between short-sighted humans attempting to establish roads, villages and towns, and the ongoing geologic processes of the landscapes they choose to inhabit.  In very recent decades, the towns of Kapoho, Kalapana and Kaimu have been inundated, destroyed and buried by Kilauea Volcano (please see a related article on the death and rebirth of Kalapana, here).  As more people move to Hawaii, more such drama is inevitable.

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Mauna Loa floats above the fields of Kohala, Hawaii Photo by Donald B MacGowan

The evolution of Hawaiian volcanoes continues even after the major phase of eruptive activity subsides. There are great differences, obvious to even the most casual observer, between the elongated, fluted ridge-like shape of Kohala Mountain and the lower angled slopes of Mauna Loa and Kilauea.  Likewise, steep-sided Mauna Kea has a greatly different physical aspect than does gently-sloped, shield-shaped Mauna Loa.  These differences are accounted for by the differences in their relative ages, and thus eruptive and erosive stages.

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The steeper, crater-poked slopes of Hualalai indicate it has moved on to the later stages of volcanism Photo by Donald B MacGowan

Remembering that the angle of repose of Hawaiian lava is about 6 degrees, the shield-shaped, gentle slopes of Mauna Loa and Kilauea reflect the fact that they are quite young and are still in the shield-building stage, being built-up by successive flows of highly fluid lava.  The much steeper flanks of Hualalai and Mauna Kea volcanoes are due to the late-stage, explosive eruptions, to erosion and to ashfall which piles up much more steeply than the flowing lava.  The fluted ridges of Kohala volcano result from the deep dissection of the once shield-shaped slopes of the original volcano by streams and surface flow of water.  The distinctive steep valleys and great cliffs seen on the north and east sides of Kohala Volcano result from later process of normal faulting and giant landslides (see further discussion in an article about Waipi’o Valley, here).

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Glacial cirques and moraines along the Mauna Kea summit ridge, Hawaii: Photo by Donnie MacGowan

Another process, operative in the geologically recent past, has served to shape the slopes of the volcanoes of the Big Island, at least those which are or great height.  Glaciers covered the summit of Mauna Kea (and possibly Mauna Loa) three times between 200,000 and 13,000 years ago, leaving behind many glacial features such as cirques, u-shaped valleys and scoured bedrock; surviving into the present is a remnant rock glacier near the summit of Mauna Kea (a related article on the summit of Mauna Kea and the Hawaiian Snow Goddess, Poliahu, can be found here; details on exploring Mauna Kea can be found here).  Any evidence on Mauna Loa of ice-age glaciers has been covered by recent eruptions.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Kohala Volcano is subsiding, cut by enormous valleys and giant cliff-forming landslides, Hawaii: Photo by Donald B MacGowan

Simultaneously with the ongoing eruptions and island building, due to their enormous mass, the great volcanoes of the Hawaiian Chain begin to subside into the oceanic crust.  After the majority of eruptions cease, with cooling and with a great amount of time, they eventually disappear beneath the surface of the sea completely, as Mahukona Volcano already has.

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Originally carved above sea level, these 500-year old petroglyphs at Keauhou today are awash due to subsidence of Hualalai Volcano: Photo by Donald B MacGowan

Today, the Big Island of Hawai’i comprises more than twice the area of all the other Hawaiian Islands combined.  It’s size is not anomalous, however, considering the geologic history of the archipelago. All the other Hawaiian Islands experienced the same pattern of volcanic eruption, growth and coalescence, as well as the gradual subsidence and submersion that Hawaii Island has, and thus at one time may have been as large as the Big Island.  Indeed, geologists have demonstrated that Maui at one time formed a single landmass, known as Maui Nui or “Big Maui”, with the islands of Lana’i, Moloka’i, and Kaho’olawe.  Continued subsidence submerged the larger landmass, leaving the four, smaller islands above the ocean surface. Ultimately, this will happen to the Big Island, as well.

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Looking from Mauna Kea summit to Mauna Loa, Hawaii: Photo by Donald B MacGowan

The relentless movement of the Pacific Plate carries it, with the all the islands piggy-backed, inexorably northward to the Aleutian Trench, where it is subducted underneath the North American Plate, melted, and recycled as volcanic material in the Aleutian Island volcanoes.  The Emperor Seamounts are currently undergoing such destruction, and, the evolution of the Hawaiian-Emperor Chain is such that, eventually this fate also awaits the Big Island…but not for tens of millions of years.

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Magical Sunset at the lava ocean entry at Waikupanaha, Hawaii Photo by Donald B MacGowan

Given the ephemeral nature of this precious island, this geologic certainty should serve to make us love and treasure the Big Island more deeply, as well as to spur us to protect and preserve it more completely.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Silent sunset descends upon Hawaii Island at Kahalu'u Beach: Photo by Donald B MacGowan

The best of Tour Guide Hawaii’s free content about traveling to, and exploring, the Big island, can be found here.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Near the summit of Kohala Mountain, Photo by Donnie MacGowan

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.

All media copyright 2010 by Donald B. MacGowan. All rights reserved.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Full moon over Mauna Kea, Hawaii Photo by Donald B MacGowan

by Donald B. MacGowan

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Visitors Watch the Halema'uma'u eruption of Kilauea at Hawaii Volcanoes National Park Graphic from Photo by Donald B MacGowan

There are many wondrous, enigmatic and fascinating attractions on the Big Island of Hawaii, some better known than others, many out of the way and generally off the beaten track. Tour Guide Hawaii has produced an encyclopedic collection of the most up-to-date information, presented as short GPS-cued videos, in an app downloadable to iPhone and iPod Touch that covers the entire Big Island, highlighting the popular and the uncrowded, the famous and the secluded, the adventurous and the relaxing.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Aerial view of Pu'u O'o Vent on Kilauea, Hawaii Volcanoes National Park Photo by Shannon Walker

The Geologic History of the Hawaiian Islands

The Hawaiian Islands, part of a much longer chain of oceanic islands and seamounts called the Hawaiian-Emperor Chain, is comprised of 8 principal islands and 124 islets, shoals, atolls, seamounts and banks, all volcanic in origin.  The Hawaiian Islands proper extend from Kure Atoll in the mid-Pacific, trending southeast to Hawaii Island (the Big Island) and Lo’ihi submarine volcano.  The eight major islands of the Hawaiian chain are named, from northwest to southeast, Ni’ihau, Kauai, O`ahu, Moloka`i, Lana`i, Kaho`olawe, Maui, and Hawai`i. Unraveling the geologic history of the Hawaiian Islands provides a fascinating glimpse into structures and process occurring deep within our Earth.  To understand how the Hawaiian Islands were formed, let’s review a bit about the nature of our planet.

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Kilauea Lava Stream, Hawaii Photo courtesy of Big Island Air

Layered like an onion, our seeming solid earth is actually a heaving mass composed of various solid, partially-molten, semi-plastic and liquid layers.  The solid crust (or lithosphere), which covers the entire surface of the earth, seems strong and robust but is, in fact, quite thin and malleable.  About the same thickness relative to the rest of the planet as an onion skin is to an onion, the Earth’s silica-rich crust more or less floats upon a much thicker, partially molten, more iron and magnesium-rich, semi-plastic layer of much hotter material called the “mantle”.  Below the mantle are the liquid outer core and the solid inner core of the Earth.

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Halema'uma'u Crater and eruption on Kilauea, Hawaii: Photo by Donnie MacGowan

Earth’s crust comes in basically two varieties, oceanic crust which is quite thin (only 5-7 km thick) and continental crust, which is much thicker than oceanic crust (up to 200 km thick).  Oceanic crust is composed almost wholly of an effusive volcanic rock type called “basalt”, its intrusive volcanic, subsurface equivalent called “gabbro” and a thin covering of sediment. The continental crust, which underlies the seven continents and the more massive islands, and upon which most human activity takes place, on the other hand, is composed not only of basalt and gabbro, but all the other rock types as well.  Continental crust is much less dense than oceanic crust, being much more silica-rich, and therefore is more buoyant on the mantle.  This, in part, accounts for its relative thickness and higher elevation compared to the denser, thinner oceanic crust.

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Lava from Kilauea flows into the sea at La'epuki, Hawaii: Photo by Donald B MacGowan

The Earth’s crust is further divided-up into various distinct pieces, called “tectonic plates”, all moving relative to each other. Plates are composed almost wholly of either oceanic or continental crustal material. These plates “float” on the semi-plastic mantle, and are carried along by currents on the mantle’s surface. Mantle currents are caused by various physical process of heat transport within the mantle.   Think of a pot of boiling soup; the point of the boil in the soup is analogous to the heat transfer in the mantle and the skim of chilled soup riding around on the surface is analogous to the moving tectonic plates carried on top of the mantle.

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Hikers pause to look over at the summit of Mauna Loa From the summit of Mauna Kea, Hawaii: Photo by Donald B MacGowan

Interactions along the edges of these plates, whether slipping past each other (such as along the San Andreas Fault), one riding up over another (such as beneath the Himalayan Mountains), or one being subducted beneath the other (such as along the western edge of North America), accounts for much of the earthquake, mountain-building and volcanic activity seen on the surface of the earth, and plate margins are certainly the most geologically active places on earth.

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Kilauea eruption in Halema'uma'u Crater at night Hawaii Volcanoes National Park: Photo by Donald B MacGowan

Occasionally, exceptions to this generality occur, and the Hawaiian Islands are one such spectacular exception. To understand the forces and process which shape the Hawaiian Islands, we must look a little closer at the origin and movement of the crust and the structure of the mantle.  Happily, we need only concern ourselves with oceanic crust in general and the Pacific Plate in particular, as well as one, singular feature of the mantle.

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Skylight at Kupaianaha Vent, Kilauea Volcano Hawaii: Photo by Donald B MacGowan

Oceanic crust is continually created by volcanic action along giant ridges which run generally north-south down the middle of the ocean basins.  The hot liquid magma at the ridges is much less dense than the surrounding, cold crustal rocks, and so “floats” these ridges and the still hot, newly-formed oceanic crust, up above the surrounding ocean basin, thus forming the ridge.  As volcanic eruptions along these ridges add hot, new material to the edge of the oceanic plates, the mass of new material drives the older oceanic crust away from the ridge, down both sides of it.  As the new material cools and becomes less dense, it sinks and further drives the crust away from the ridges.

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Lava Flowing Into the Sea at Waikupanaha, Hawaii Photo by Donald B MacGowan

Called “Mid-Ocean Ridge Spreading”, this process can be likened to a conveyor belt where new crust is created at the mid-ocean ridge, and is driven along by buoyancy and gravity, farther and farther away from the ridge until the plate’s leading edge interacts in some way with another tectonic plate.  Thus we see that the floors of the ocean basins, all around the world, are in constant, relative motion.  The Pacific Plate, upon which the Hawaiian Islands are built, has been moving at a rate of about 3.9 inches per year to the northwest, relative to other plate motions, for about the last 42 million years.

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Sunset on Haleakala from Kiholo, Hawaii Photo by Donnie MacGowan

But what causes the enormous volcanoes that comprise the Hawaiian Archipelago to form in the middle of the ocean basin?  As mentioned above, the mantle is far from uniform either compositionally, thermally or in terms of the processes controlling its internal motions.  There are places on the earth where, for a variety of reasons, hot and buoyant mantle plumes rise above the general surface of the mantle, into the crust, carrying great amounts of heat and semi-liquid material quite near the earth’s surface.  Called “Hot Spots”, extreme volcanism can result from these thermal plumes.  The volcanic fields at Yellowstone in North America are one such example of this “hot spot magmatism”; the Hawaiian Islands are yet another.

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The heavily-dissected mountains of Kauai completely obscure the original shield shape of the volcano Photo by Donald B MacGowan

The Hawaiian Hot Spot has caused the creation of at least 129 volcanoes on the ocean floor, the center of volcanism on the Pacific Plate continually migrating across the plate as it travels over the hot spot. Of these 129 volcanoes, 123 are extinct, three are dormant and three are active.  At first, the trend of volcanoes was almost due north-south.  Then, somewhere between 41 and 43 million years ago the relative motion between the Pacific Plate and the hot spot changed, becoming more northwesterly; this caused a sharp bend in the line of island-forming volcanoes.

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Aerial view of Pu'u O'o vent on Kilauea Volcano, Hawaii Volcanoes National Park Photo by Donald B MacGowan

Although all were formed by the same, continuing tectono-volcanic processes, two island groups are named from this bent line of islands, atolls and seamounts.  North of the bend are the Emperor Seamounts, a long chain of islands, seamounts, atolls and reefs trending steeply southeast to northwest between Abbot Seamount in the mid-Pacific and Meiji Seamount near the Aleutian Trench.  South of the bend are the Hawaiian Islands, trending from the active volcanism at the Big Island and Loihi Volcano today, gently northwest to Kure Atoll in the mid-Pacific. Movement of the Pacific Plate over the hotspot is such that Midway and Kure Atolls were where the Big Island is now, directly over the hot spot, about 30 million years ago.

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The steep sides of Mt. Rainier in Washington result from its relatively high-silica, viscous lava Photo by Donald B MacGowan

The chemical composition of the Hawaiian magmas plays a central role in determining the physical form of the Hawaiian Islands.  All crustal rocks are formed of minerals composed of aluminum and silicon oxides with varying amounts of iron, magnesium, sodium, calcium, potassium and other elements stirred in.  In lava, silica tends to polymerize and greatly increase the viscosity of the melt—thus silica-rich lavas are fairly “sticky”, forming slow moving lava flows that pile-up into steep volcanoes which are typified by explosive eruptions. Silica-poor melts, on the other hand, because they are not so polymerized, form very fluid lavas that flow quickly and easily, forming gently-sloped volcanoes typified by relatively quiescent eruptions.  Remember the key words here are: “relatively quiescent”.

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Mauna Loa floats above the fields of Kohala, Hawaii Photo by Donald B MacGowan

One glance at the profile of the Hawaiian volcanoes is enough to convince us that the lavas must be very silica poor, since they are very gently-sloped and the eruptions relatively peaceable; certainly civilized enough so that the casual viewer may approach them quite closely in relative safety.  Compare these with the very steep-sided, highly explosive eruptions of volcanoes like Mt. St. Helens, which is comprised of lava much more intermediate in silica composition, or the smoking hole in the ground that is the Yellowstone volcanic field, left by a massively explosive, very silica rich (and very, very viscous) lava erupting.

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Layered basalts in Waimea Canyon on Kauai show the structure of the Island, flow upon flow: Photo by Donald B MacGowan

The rocks formed when the lava from Hawaiian volcanoes hardens are called “basalt”.  Although you hear the term “lava rock” used by laymen, it is a nonsensical word geologically and the registered trademark of a commercial product.  Commonly misapplied, it makes even less sense than the equivalent of using the term “water solid” instead of “ice”. The name “basalt” denotes both the silica-poor composition, as well as the fact that it was erupted onto, and it has cooled at, the Earth’s surface.  When lavas cool within a magma chamber before being erupted onto the surface, they are called an “intrusive volcanic” rock; intrusive volcanic rocks formed from lavas of basalt-like composition are called “gabbros”.  There are a few rocks in the Hawaiian islands of differing composition and texture than basalt and gabbro, but they are unimportant to this discussion.

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The classic, low-angle shield shape of Mauna Loa seen from Hilo, Hawaii Photo by Donald B MacGowan

The angle of repose, which is controlled by the viscosity of the melt, is about 6 degrees for Hawaiian basalts. Melt viscosity is a function of its temperature, silica content and fluid composition.   Hawaiian basalts are very fluid because of the low silica content and high eruptive temperature (in excess of 1100 degrees C); this low viscosity accounts for low angle, “shield shape” of Hawaiian volcanoes.

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Kohala Volcano is dissected by several major fault-bounded valleys, further obscuring its original shield shape Photo by Donald B MacGowan

As soon as the Hawaiian volcano forms, other forces begin to act upon it, affecting the general “shield shape” of the volcano: tides and waves attack the edges, rivers and streams begin to dissect the shield into ridges.  As time goes on, erosion from surface water flow produces fluting along those ridges.  Great landslides produce enormous cliffs; faulting produces huge valleys and collapse produces enormous craters and calderas.  Further, the later stage of Hawaiian volcanism is typified by increasing violence, which makes deep explosion craters, steep-sided cinder cones and steeply sloped, but easily eroded, ash deposits.

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Stream erosion dissects the shield volcanoes into valley and knife-like ridges Photo by Donnie MacGowan

To look at the volcanoes of Hawaii starting in the southeast at Kilauea and Mauna Loa and moving northwest, one can see this evolution quite clearly.  Kilauea and Mauna Loa, being quite young, are still broad and shallow-sloped, basically the classic shield-shape.  Mauna Kea and Hualalai are obviously more mature, showing steeper slopes, a reflection of greater ashfall and greater erosion, as well as pocked with explosion craters and cinder cones.  Moving father along, Kohala Mountain is so deeply eroded and festooned with long, fluted ridges as well as cut by enormous canyons, that it is almost unrecognizable as a shield volcano.  And so it continues as one proceeds north through the older islands and the more highly eroded mountains; the original shield shape of the volcanoes become more and more obscured by deeper and deeper erosion.  By the time one gets to the famous and spectacular Na Pali Cliffs of Kaua’i, all that is left of the original volcano are the deeply fluted, now almost knife-like, ridges.

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Ancient Petroglyph, Keauhou Historic District, Hawaii Photo by Donald B MacGowan

The great mass of these volcanoes causes them to begin to sink back into the mantle.  This is evident on even relatively young volcanoes.  For instance, on the slopes of Hualalai Volcano on the Big Island, along the shore at Keauhou, numerous petroglyphs commemorating the famous victory of King Lonoikamakahiki of Hawaii over King Kamalalawalu of Maui were carved in the rock around the end of the 16th century.  Although when they were originally carved they stood above sea level, in the intervening four centuries, the island has sunk sufficiently that they are now mostly awash in the sea and submerged at high tide.

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Glacial cirque and terminal moraine on Mauna Kea, Hawaii Photo by Donald B MacGowan

Another process, operative in the geologically recent past, has served to shape the slopes of the Hawaiian volcanoes, at least those which are or great height.  Glaciers covered the summit of Mauna Kea (and possibly Mauna Loa and Haleakala) three times between 200,000 and 13,000 years ago, leaving behind many glacial features such as cirques, u-shaped valleys and scoured bedrock; surviving into the present is a remnant rock glacier near the summit of Mauna Kea.

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Valleys and Ridges of the Famous Na Pali Coast, Kauai Photo by Donald B MacGowan

The complex interaction of volcano growth, coalescing of various volcanoes forming a single island and the eventual subsidence of the volcanoes into the crust determines the shape and size of the individual Hawaiian Islands through time.  Today, the youngest islands are largest and the oldest islands, generally, are the smallest…this trend continues throughout the Hawaii Island/Emperor Seamount chain.

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Lava flows from Kilauea to the sea at Waikupanaha, Hawaii Photo by Donald B MacGowan

In the case of the Big Island, even though the first volcano to form, Mahukona, has completely subsided below sea level, the Big Island still comprises more than twice the area of all the other Hawaiian Islands combined, due to the large number of volcanic peaks forming it. However, through their history, all the Hawaiian Islands will experience the same pattern of growth, coalescence, subsidence and submersion, and so may have been much larger at one time.

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Haleakala from Kohala, Hawaii Photo by Donald B MacGowan

Maui, today comprised only of the remnant peaks of Haleakala and the West Maui Mountains, at one time formed a single giant landmass with the islands of Lana’i, Moloka’i, and Kaho’olawe.  As the continual northwest movement of the Pacific Plate carried Maui away from the Hawaiian hot spot, continued subsidence submerged the larger landmass, known as Maui Nui, or “Big Maui”, into the oceanic crust, leaving only these four, very much smaller, islands above the surface today.

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Superstition to Science, Pu'u Weiku Summit, Mauna Kea Photo by Donald B. MacGowan

In fact, Kaua’i, Ni’ihau and O’ahu all represent the tiny remnants of once much larger landmasses that are actively subsiding into the oceanic crust.  Tracing the Hawaiian Archipelago to the northwest, and thus to very much older islands, we see this evolution continue as the great volcanoes are completely submerged below the surface leaving only the fringing coral reefs and a tiny remnant island above sea level, such as we see at Laysan Atoll and Midway Island. Continuing along through the chain to the Emperor Seamounts, not even that much is left as all traces of these islands, once proud and beautiful like the Hawaiian Islands today, become totally submerged beneath the surface of the ocean.

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Alpen Glow on Hualalai Volcano and Sunset on Kailua Kona Hawaii: Photo by Donald B MacGowan

Add to this mental picture the fact that the Pacific Plate relentlessly drives northwestward, carrying all the Hawaiian-Emperor Chain with it, northward to the Aleutian Trench, where it is subducted and destroyed beneath the North American Plate.  Eventually, in the far-distant future, this fate awaits all these beautiful, precious islands.  Such is the ephemeral nature of the Hawaiian Islands, and this vision of their very delicate and temporary nature should make us respect and wonder at their splendor and beauty, all the more.  And increase our desire to protect and preserve them.

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The steeper, crater-poked slopes of Hualalai indicate it has moved on to the later stages of volcanism Photo by Donald B MacGowan

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Watching Lava Pour Into the Sea at Waikupanaha, Hawaii Photo by Donald B MacGowan

All media copyright 2010 by Donald B. MacGowan. All rights reserved.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts   the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and   WiFi enabled, dozens of videos…available at iTunes or   www.tourguidehawaii.com.

Lava ocean entry, Waikupanaha, Hawaii: Graphic from Photo by Donnie MacGowan

by Donald B. MacGowan

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Mauna Loa from Kipuka Pu'u Huluhulu, Hawaii: Graphic from Photo by Donald B MacGowan

There are many wondrous, enigmatic and fascinating attractions on the Big Island of Hawaii, some better known than others, many out of the way and generally off the beaten track.  Tour Guide Hawaii has produced an encyclopedic collection of the most up-to-date information, presented as short GPS-cued videos, in an app downloadable to iPhone and iPod Touch that covers the entire Big Island, highlighting the popular and the uncrowded, the famous and the secluded, the adventurous and the relaxing.

Kipuka Pu’u Huluhulu Nature Trails and Kipuka Aina Hou Nene Sanctuary

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Morning light on Kipuka Pu'u Huluhulu, Saddle Road, Hawaii: Photo by Donnie MacGowan

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 at the summit of the Saddle Road. Kipuka Pu’u Huluhulu is famous for the number and variety of rare and endangered Hawaiian plants and birds that inhabit it.

Kipuka Huluhulu is located at the intersection of Highway 200, the Saddle Road, and the Mauna Kea Access Road, John Burns Way, at mile marker 28. Early morning, when the birds are active and the sun shines on a slant (making views more dramatic and the birds easier to spot) is the best tome to visit the Kipuka.

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Mauna Kea from Kipuka Pu'u Huluhulu, Hawaii: Photo by Donald B MacGowan

Kipuka are small stands of grassland and forest that have become isolated by lava flows through time. As tiny island in the greater landscape, they can become become biologically cut-off from the rest of the ecosystem. Species can rapidly mutate, adapting to the special conditions in the kipuka, very, very rapidly and biologists have found new subspecies of insects and plant in kipuka that have only been isolated half a millennium, or so. The 38 acre Kipuka Huluhulu, which was deforested by cattle over-grazing and isolated by the 1843 and 1935 lava flows, represents a window view of what the Koa forest here may have looked like.

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The trail to the top of Kipuka Pu'u Huluhulu, off the Saddle Road, Hawaii: Photo by Donnie MacGowan

It’s name meaning “furry hill”, this forested cinder cone has three main trails winding up through rare native koa trees, and other rare and endangered flora, to breathtaking 360° views of Hualalai, Mauna Kea and Mauna Loa at the top. Here you can also wander a meadow of native Hawaiian plants recently reintroduced in this protected habitat. By whatever trail, the summit of Kipuka Pu’u Huluhulu is only about 25 minutes walk from the car.

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Mauna Kea from Kipuka Pu'u Huluhulu, Hawaii: Photo by Donnie MacGowan

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 the adjacent Humu’ula area. lava flows makes for interesting, if hot and dry, mountain biking and hiking.

Remember that is is a protected wildlife area and that the fences are there to keep destructive wild goats and feral pigs from coming in and damaging the delicate ecosystem. Please do not fail to close all gates behind you as you enter and exit. Parking and a unisex pit toilet are the only amenities available at Kipuka Pu’u Huluhulu.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Hualalai and the Saddle Road from Kipuka Pu'u Huluhulu in the Early Morning Light, Hawaii: Photo by Donnie MacGowan

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.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Kipuka Pu'u Huluhulu from Mauna Kea Access Road, Hawaii: Photo by Donnie MacGowan

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

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand. Interactive maps, GPS and WiFi enabled, dozens of videos…available at iTunes or www.tourguidehawaii.com.

Saddle Road at Kipuka Pu'u Huluhulu, Hawaii Island: Graphic from Photo by Donnie MacGowan

by Donald B. MacGowan

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand, available at iTunes or www.tourguidehawaii.com.

Kohala Mountain Road, Kohala Hawaii: Graphic from Photo by Donald B MacGowan

There are many wondrous, enigmatic and fascinating attractions on the Big Island of Hawaii, some better known than others, many out of the way and generally off the beaten track.  Tour Guide Hawaii has produced an encyclopedic collection of the most up-to-date information, presented as short GPS-cued videos, in an app downloadable to iPhone and iPod Touch that covers the entire Big Island, highlighting the popular and the uncrowded, the famous and the secluded, the adventurous and the relaxing.

Kohala Mountain Road

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Through the ironwood forests on the Kohala Mountain Road, Kohala Hawaii: Photo by Donald B MacGowan

Highway 250, the Kohala Mountain Road, is the direct, over the mountain connection from Waimea to the towns of Hawi and Kohala through the heart of ranching country. Cresting at over 3500 feet on Kohala Mountain, this almost 22-mile long road is one of the most scenic, but least driven, on the island.

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Looking from Kohala Mountain to Mauna Kea, Kohala, Hawaii: Photo by Donald B MacGowan

Known for its panoramic views, its thick, drifting mists punctuating long, sunny days and wide open spaces separated by ironwood forests, the Kohala Mountain Road packs a lot of spectacular scenery characterized by ceaselessly changing moods in its short run. If you are traveling to the north end of Hawaii Island, this road is a highly-recommended scenic drive.

There is a scenic turnout, way above Kawaihae Town down on the coast, about 6 miles out of Waimea that should not be missed; it has one of the most commanding views in all Kohala. Sunset views of Haleakala on Maui and the Kohala Coast are especially fine from this turnout.

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Fence line along Kohala Road, Kohala Hawaii: Photo by Donald B MacGowan

Offering spectacular views of Kohala, Mauna Kea and Hualalai Volcanoes, the Kohala Coast, forest and prairie, the Kohala Mountain Road leaves Waimea Town on its western margin at Lindsey Road. About a mile north out of town, the Kohala Mountain Road branches east (uphill) from the Kawaihae Road (Route 19), which runs down to the coast at Kawaihae Town. Coming from Hawi, take the main road north out of town, Hawi Road, from its intersection with the Akoni Pule Highway (Highway 270); from Kohala, take Kynnersley Road north from its intersection with Union Mill Road and the Akoni Pule Highway.

From a scenery standpoint, this road is beautiful going either direction, but is absolutely breath-taking headed south to north. There are no services of any kind between Waimea Town and Hawi.

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Rainbow and Kohala Coast from Kohala Mountain Road, Hawaii: Photo by Donald B MacGowan

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.

New at iTunes: Hawaii Dream Vacation iPhone/iPod Touch App Puts the Magic of Hawaii in the Palm of Your Hand, available at iTunes or www.tourguidehawaii.com.

Kawaihae Harbor from Kohala Mountain Road on a perfect Blue Hawaii Day--you cannot see where the sky begins or the ocean ends: Photo by Donald B. MacGowan

At Tour Guide our goal is to insure you have the most fun, most interesting and enjoyable vacation here in Hawaii–that you are provided with all the information you need to decide where to go and what to see, and that you are not burdened with out-dated or incorrect information.

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Big Sky Views from the Enchantingly Scenic Kohala Mountain Road, Kohala Hawaii: Photo by Donald B MacGowan

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Kohala Mountain Road showcases the ranching heritage of the Big Island of Hawaii: Photo by Donald B MacGowan1

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



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.
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.

————-

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!

This post has been updated and expanded here.

Feeling hemmed in by the spring drizzle in Kona, the Men of Tour Guide decided to take a much needed break and drive from Kailua Kona across The Saddle Road, up to the summit of Mauna Kea and down into Hilo.

Hualalai Volcano and Pu'uanahulu on the Big Island: Photo by Donald MacGowan

Hualalai Volcano and Pu'uanahulu on the Big Island: Photo by Donald MacGowan

Driving out of Kailua Town on Highway 190, we passed Pu’unanhulu on the backside of  Hualalai Volcano, continuing to the junction with Highway 200, The Saddle Road, famed in song, legend and fable.

Looking Back Toward Kohala Mountain from Saddle Road: Photo by Donnie MacGowan

Looking Back Toward Kohala Mountain from Saddle Road: Photo by Donnie MacGowan

Saddle Road has a nasty reputation, which is only partly deserved.  Having been rebuilt from Hilo-side up over the saddle, there are only a dozen or so miles of rough, single lane roadway remaining.

Stopping at The Saddle, we decided to hike up Pu’u Huluhulu, the Shaggy Hill, a wildlife preserve on a prominent kipuka, or living island between lava flows.

Mauna Kea from Kipuka Huluhulu: Photo by Donald B. MacGowan

Mauna Kea from Kipuka Huluhulu: Photo by Donald B. MacGowan

Kipuka Huluhulu offers superb views of Mauna Loa and Mauna Kea, as well as fabulous bird watching and a grand nature trail through a lot of native flora.

Vanishingly Rare Silver Sword Plant on Mauna Kea: Photo by Donnie MacGowan

Vanishingly Rare Silver Sword Plant on Mauna Kea: Photo by Donnie MacGowan

Taking John Burns Way from The Saddle up to the summit of Mauna Kea, we stopped at the Visitor’s Information Station for a rest stop, to acclimatize and to photograph some Silver Sword plants; one of the rarest plants on earth, Silver Swords grow only on Mauna Loa, Mauna Kea and Haleakala.

From the Visitor’s Information Station we made our way up to the summit road.  This road, too, has an only partially-earned nasty reputation.  True, the road is mostly graded rock (it gets graded 3 times a week); true, it’s steep and narrow with NO shoulders and scary drop-offs; and, true, the weather can turn in a heartbeat from warm and sunny to full-on blizzard white-out.

The Men of Tour Guide Hard at Work on Mauna Kea: Photo by Donald B. MacGowan

The Men of Tour Guide Hard at Work on Mauna Kea: Photo by Donald B. MacGowan

However, anybody who has experience driving on dirt roads in the mountains and drives cautiously is apt to be just fine…afterall, it’s not the roughness of the road that keeps people from the summit, it’s the lack of air at altitude that kills the car. If you are in doubt about the drive, the Rangers at the Information Station can help you decide if you should drive up or not.

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

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

The summit of Mauna Kea is one of my favorite places in all of Hawaii.  I’ve been here at all times of the day and night, in all kinds of weather; I have stood at the summit and seen the North Star and the Southern Cross in the same sky on the same night; I have skied and snowboarded from the summit and hiked to the top from sea level.  I’ve ridden my mountain bike up and ridden my Honda Ruckus scooter from Kailua Town up.

Mauna Kea Summit Temple: Photo by Donald B. MacGowan

Mauna Kea Summit Temple: Photo by Donald B. MacGowan

I love this mountain.  In September of 2006, Sean O’Neil, a paraplegic, rolled his wheelchair to the summit all the way from sea level in Hilo. All I could think when I heard he’d made the summit was “There is a real adventurer with the heart of a lion…”.

Rolling our own way back down the John Burns Way to The Saddle Road, we discovered the spring monsoon was still in full swing as we headed east towards Hilo Town.  Of course it was raining on Hilo Side! Stopping in the foothills just west of Hilo, we spent some time exploring around Kaumana Caves, a lava tube that extends for 25 miles, formed in the 1881 eruption of Mauna Loa.

Frank Descends Into Kaumana Cave: Photo by Donald MacGowan

Frank Descends Into Kaumana Cave: Photo by Donald MacGowan

Entrance is gained at Kaumana Cave County Park by a concrete staircase descending into a skylight.  The adventurer is immediately faced with a question: explore the uphill portion or the downhill portion?  Whichever route you take, be sure to have 3 sources of light, a hard hats (knee pads are nice, too) and be prepared for wet and slippery rocks. If you’re not intent on exploring deeply, a walk into the portions where sunlight penetrates is still pretty amazing.

Looking Out Kaumana Cave: Photo by Donald MacGowan

Looking Out Kaumana Cave: Photo by Donald MacGowan

Continuing on into Hilo, we spent some time at Rainbow Falls, which, because of the recent rain, was swollen and immense.

Rain-Swollen Rainbow Falls: Photo by Donnie MacGowan

Rain-Swollen Rainbow Falls: Photo by Donnie MacGowan

I explored the river a bit above and upstream of the falls and found an incredible tract of wild urban jungle (if that is not actually a contradiction in terms, it’s at least a brilliant name for a rock band…) and lots more smaller falls, continuing on up the river.

THe Jungle Behind Rainbow Falls: Photo by Donald B. MacGowan

The Jungle Behind Rainbow Falls: Photo by Donald B. MacGowan

There is a trail along portions of this.

It was getting late as we explored downtown Hilo so we gassed the car and decided to drive home through Waimea.

Hualalai Sunset from Highway 190, Big Island, Hawaii: Photo by Donald MacGowan

Hualalai Sunset from Highway 190, Big Island, Hawaii: Photo by Donald MacGowan

Kailua Kona Sunset from the Pier: Photo by Donnie MacGowan

Sunset over Thurston Mansion from the Kailua Pier: Photo by Donnie MacGowan

We blazed along laughing at our day’s adventure under an increasingly amazing sunset, arriving back in Kailua Town just in time to catch a meal of Kona Dogs and raspberry smoothies at Cousin’s in the Kona Inn Shops.  Best raspberry smoothies on the island, I’m telling ya!

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

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