It’s Volcano Week 4 here at GSS. Volcanoes, about a week. You know the drill!

Newberry Volcano is an immense shield volcano located in central Oregon. In addition to a main volcanic caldera, the system is composed of many domes, cones, craters and lava flows across an area more than 32km in width in addition to two large fissures which extend outwards a considerable distance.

The central caldera, known as Paulina Peak, was created over hundreds of thousands of years and many eruptions; it now contains a pair of lakes fed by hot springs – Paulina Lake and East Lake. Extreme temperatures have been recorded beneath the caldera, leading to exploration with a view to creating geothermal power. The lava flow to the south of the lakes is known as Big Obsidian Flow.

Newberry Volcano is noted for creating many different types of lava, with a corresponding variety of landscape features being created as a result. The entire system is protected as the Newberry National Volcanic Monument. Apollo-era astronauts trained in areas of the volcano that resemble the moon’s surface.

Some of the most prominent features are buttes – tall cinder cones which result from a single eruption, including this cluster north of the lakes.

One of the most prominent is Lava Butte, which is approximately 150m tall, and has the Lava Lands Visitor Center at its base. Lava Butte is visible in a quite scenic Street View image from nearby Highway 97 … though it appears to have been so cold that one of the camera lenses froze over!

There are three large lava fields (mostly flat areas of volcanic rock) to the southest of the caldera – Devil’s Garden, Squaw Ridge and Four Craters. Extending from the edge of the latter is the imaginatively-named Crack-in-the-Ground, a 20m deep and 3km long fissure which is popular with hikers.

Equally creatively-named are the two nearby large maars, or explosion craters – Big Hole and Hole-in-the-Ground.

It’s Volcano Week 4 here at GSS. Volcanoes, about a week. You know the drill!

Rising up from the pastoral plains of Luzon Island in the Philippines is Mount Mayon, an active 2,400 metre-high stratovolcano. Known as the “perfect cone,” Mayon Volcano looks surreal in its symmetry, a true masterpiece of nature.

The volcano rises up in stark contrast to the surrounding flat terrain, its upper slopes averaging a 35-40 degree grade. Eruptions occur primarily from a small volcanic crater but have also created pyroclastic flows that carved over 40 ravines around Mayon’s cone. Viewing Mt. Mayon in Google Earth shows its unique shape:

With 47 eruptions since 1616, it is the most active volcano in the Philippines and remains a danger to nearby villages even today. Its deadliest eruption took place in February of 1814 and killed over 1,300 people. During that Pompeii-style eruption, Mayon Volcano reportedly spewed plumes of hot ash while fast-moving lava flows completely covered the village of Cagsawa. The town’s bell tower was the only structure left standing after the eruption had ended.

In recent decades, Mayon Volcano has continued to make its presence known in the region. With eruptions in 1984, 1993, 2006, and 2008, the residents of nearby towns and villages have become accustomed to frequent evacuation warnings and safety alerts. If you’re one of those adventurous¹ types who likes a steep uphill climb, try Mount Mayon, but be sure to wear a helmet and watch for falling debris and hot magma.

It’s Volcano Week 4 here at GSS. Volcanoes, about a week. You know the drill!

Beauty sometimes erupts from utter disaster. Take, for example, the gorgeous crater lake that formed in the remnant bowl of the 1991 Mount Pinatubo eruption in the Philippines. A stunning natural wonder was created from one of the largest, most devastating volcanic eruptions in the past 100 years.

No one knew there was volcanic action happening far below the surface of Pinatubo. The local indigenous people, the Aeta, had no recollection of any previous blasts in their oral history and geologist data was scarce as well.

Yet, during the month of June, 1991 the mountain spewed forth 10 cubic kilometres of hot, molten magma; injecting more aerosols into the stratosphere than that of Krakatoa – one hundred years before.

Due in part to Typhoon Yunya that was ripping through the island nation, the ash cloud that should have been spread over the surrounding oceans instead cycloned back over the Luzon region, where Pinatubo once lay dormant.

The mixture of the typhoon force winds and rain with the ash cloud resulted in a rainfall of heavy mud causing considerable damage to neighboring cities. This included the already evacuated Clark Airbase, a U.S. Air Force establishment, whose many flat-roofed buildings collapsed under the weight of the ash and mud.

The military never permanently returned to the base, instead they turned it over to the Philippine government, who converted half of it into a Philippine Air Force base and the other half into a Holiday Inn Resort complex.

It is easy to see the ravines and canyons coming down the sides of the mountain that are now filled with lahar, a volcanic mud mixture. Lahar filled river beds streak the landscape leading away from Pinatubo.

After years of rainfall, the basin of the once-mountain filled with water to form Pinatubo Crater Lake. Now a tourist destination, many will trek for several hours through deep jungle trails to reach the clear waters of the lake.

Back in 2002, the lake had filled the crater so much that there was fear that the rim might collapse, causing considerable damage to local farms and endangering some 45,000 residents in neighboring villages.

To prevent such a collapse, the government commissioned engineers who sand bagged a makeshift river bed, using a lahar mudflow path, 5 metres wide and then cut a notch the same width in the lowest part of the crater’s rim. They managed to drain off 25% of the crater’s water into the nearby Bucao River.

All in all the blast at Pinatubo caused the displacement of hundreds of thousands of people, the deaths of over eight hundred, and damaged billions of pesos worth of property, buildings, and farmland. But, they got a very beautiful lake out of it – that is, if you’re willing to make the trek.

It makes the team here at GSS feel positively web-ancient, but today sees the return of our very-long-running series Volcano Week!

Now in its fifth year¹ Volcano Week² is devoted to sights created by the process of molten rock, mud, hot ash and/or gases escaping from craters, lava fields, cracks, fissures, openings or ruptures in the Earth’s (or any other planet’s) surface or crust.

Um, where was I?

Volcanoes. A week of them. You get the picture.

In the meantime, refresh your memory with our volcano posts from previous years:

• 1st annual Volcano Day (2005)
• 2nd annual Volcano Day (2006)
• Volcano Week 3 (2008)
• All our volcano posts

You can also browse Wikipedia’s exhaustive lists of volcano locations (we’re still accepting suggestions for posts later in the week!), or finally, try these Google Earth layers, one of which shows current volcanic activity.

Krakatoa is probably the most famous, and deadly, of all volcanos worldwide.

The eruption of August 27, 1883 was so immense that it easily tops the loudest recorded noise in human history, being heard clearly over 5000 km away.

Around a trillion cubic feet of rock, pumice and ash was thrown up into the air, affecting global weather systems and even painting the sky red¹.

When it erupted, two-thirds of the island which Krakatoa occupied was blown apart and caused massive tidal waves, killing thousands of people.

The remains of that original Kraktoa Island is actually 5 km to south and the island which Kraktoa now occupies was “self-built”. Created from subsequent eruptions it broke the surface in 1928 and was dubbed “Anak Krakatau”, or “Child of Krakatoa”.

As we can see “Anak Krakatau” continues to expand, having increased in size by about 5 inches per week since the 1950s.

Read more on Wikipedia.