Episode 3 Volcano Live

25 years ago this is what the small Hawaiian community Kalapana looked

like. Lush, green and vibrant it was home to 3,500 people. And this

is what it looks like now. In tonight's show we're going to show

you what happened here and explain why our planet is just so active.

This is Volcano Live. Welcome to Hawaii. Welcome to Volcanoes Live.

We are in Kalapana on the south- eastern flank of the Kilauea

volcano, which has been our home for the last three nights. It is

the most active volcano in the world, and here you can really see

the devastation that it has wreaked in the last few years. In 1990, a

lot of lava work from the east rift came down and took out a community

here, but amazingly, people are coming back and building their

houses. They, are and we're going to be meeting someone in just a bit

who has made that choice, who is rebuilding their home in this

desolate landscape, but first, let's see what else is coming up on

today's programme. Tonight:

I take a Jules Verne-style adventure into the centre of the

earth. I explore eruptions and earthquakes. Team of

volcanootionologists turn to violence, but all in the name of

silence. And Ed Byrne finds out what turns an innocuous wave into a

deadly tsunami. Lots to look forward to and you can

Or you can Tweet us. Let's give you a little bit of a reminder where we

are. We're right in the middle of the Pacific Ocean, the island chain

the archipelago of Hawaii, and we're on that Big Island at the

bottom. Now, yesterday, we were at the site of the 1969 eruption on

Mauna Ulu, another part of the killer volcano. On the show, we

packed up and moved down here to the coast. It's quite warm here. We

got used to being in the cold in the mist, but now we're in the

balmy coastline. We keep talking about Kilauea being the most active

volcano in the world. The reason for that is in 1993 lava started

pouring out from the east rift over there. You can see it - along the

rift is a line of fissures and craters. That's where the lava came

out of. Down here that lava is cold. We can walk on it fine, but if you

across to the foot of that slope, there is a lot of red stuff coming

out. You can see the scale of it. It almost looks like a kind of lava

ocean, doesn't it? Ever so often you get what you call break-out,

rivers coming down. In other parts you get a hint of magma flowing

underneath. It is an extraordinary sight to think that what looks like

a dead landscape, which has been active and is no longer active,

suddenly there are points which reMind you just of the force of the

volcano. Exactly. It's good to get an idea of how volcanoes move that

slow creeping across the landscape. Our time-collapse cameras have been

set up at the edge of the volcano. You can see how it does creep in

this insidious way. It's addictive watching it. It's hypnotic. It is.

It's a beautiful movement, but as you said yesterday not a killer

because it's so slow. The thing is it's so hot, you can't get a feel

of how hot it is unless you see it at night. You can see the creeping

lava. It starts to fire off - little bits of vegetation starts to

burn, so those temperatures are easily 500, maybe 700 degrees.

is a spectacular sight, less spectacular probably if you were

one of the people living here when the lava flows started heading this

way. We have some extraordinary footage of the day the lava crept

towards this community, and as you can see, it was a slow creep.

People were able to rescue their possessions. They were able to move

- even move buildings. That's the church. The church moving - it's

extraordinary. That's now about five miles down the road, but what

a lot of people weren't able to do was obviously to move their houses,

and the inevitable happened. What we must emphasise - absolutely no-

one was killed in that eruption, but it did leave something like 180

houses destroyed - many of them, sadly, under this lava. It's

slightly eerie walking here because underneath are people's homes. Many

times you get the debris of people's homes. You do. If you walk

around the lava here, you can see what looks like people have just

dumped rubbish. They haven't at all. The furniture you can see, the

bathtub - those are actually entombed in lava. The car is one of

the iconic images. It's a real reminder that this was once a

vibrant community, and you would think that now it would be

completely deserted, but that's not the case because just over there

you can see that there are houses back being built on the lava. Now,

that does seem to be an extraordinary - well, a madness,

really. Well, one of the people that has moved back to Kalapana is

Robert McKnight. Good morning. morning. Lovely to see you. Thank

you for joining us today. You're welcome. Can you tell me when you

moved here for the first time? moved out here on the lava about

2005 I think it was, yeah. So there had already been lava flows - the

very destructive lava flows we saw in that earlier film - had already

happened? Yes. So you made a conscious decision to move to a

place that had already been wiped out by a volcanic eruption? Yes, I

did! Now, you laugh about that, and actually, we have had questions

about people like you - I mean, you're not unique. There are plenty

of people the world over who live in the shadow of volcanoes. One of

our viewers, John, from Staffordshire, said, "Why do people

insist in living near volcanoes even though they know the dangers?"

why did you decide to move here? think the biggest reason was the

openness of the area. It lacked mosquitoes and frogs, so that was

something - I was allergic to mosquitoes, and probably one of the

most important factors for me was the opportunity to get ocean-front

land that was very reasonable in price and still just beautifully

expansive, and the weather is great out here. The small issue of lava

covering me was put in the background, and - you know...

you slightly think, it's happened already. It probably won't happen

again? Was that sort of in the back of your mind? It did. It was

actually pouring a few miles past my house into the ocean. I just

felt that the width of the lava pouring down the mountainside would

be a high chance of running me over again, but lo and behold, you know,

the Pu-u O'O vents shut down from an earthquake and moved eastward a

few miles, and sure enough, it came down the hillside and went right

next to my house and eventually took the house. So at that point, I

mean, how - can you describe how it feels? You know, for us, we live in

a very benign country. In England, we don't have any volcanic

eruptions. How does it feel to witness that very slow creep of

lava towards the thing that you've built with your own hands? You must

have felt very emotional at that moment? I was, and reflecting maybe

on people that were here 15 or 20 years earlier that had a lot of

green vegetation and homes - they watched the pulsing of the lava

coming and stopping and coming. It's torturous because it may or

may not take your place, so there is a lot of waiting. It certainly

interrupts one's life completely, and it's painful no matter what to

see one's own house go up in flames and get covered. I suppose that

then makes your decision to come back even more extraordinary

because you lost your home - all of those years of work building it.

You'd come, as you say, to your bit of paradise, and yet if we look,

we've got a camera I think just over there. You are rebuilding

again. Rebuilding. You're just a glutton for punishment, Robert?

hope not. There were financial choices, of course, too. I couldn't

hop on a jet and go where I wanted to, so it left me, unfortunately,

with - out the assets to do much, with and that property once again

was inexpensive - less expensive than my ocean front. I am slightly

surprised you have to pay for it at all. Aren't they just giving it

away? Some people feel that way and don't want to live here, but those

of us who do - it is just a wonderful atmosphere if you're not

looking at lava coming at you. Unfortunately for my second place

that I quickly got to have a place to live in, actually, after losing

my actual house - the lava after two years' time wound up 300 feet

off of my doorstep again, and I was looking out at a very real threat

of the lava covering me. My house wasn't, again, finished at the time,

but that was, you know, a very terrible feeling that I just can't

have that happen to me twice. Twice! And it subsided, actually

has moved back to where it had been years before, so I get a little

reprieve - at least to get my house finished and insurance on it this

time. I won't have the financial losses, you know, just kind of the

emotional - but, you know, with this compensation. But how would

you describe the community that do live here? Do you think - are you

kind of pioneers? What - how do you describe yourselves? I don't know.

Everyone out on the lava I think is looking for, you know, the nice

weather, and it is the expense. Homes were getting very expensive a

few years back, and for the average person, it's stressful to find

their paradise in Hawaii, so people that are out here on the lava can

enjoy all the amenities of living in Hawaii, but, you know, the real

estate itself is affordable. kind of unique. And very unique

also, so there are a lot of pluses here, and everyone that does live

out here in these communities now really do appreciate being out here.

They really like being out here. Well, Robert, it is a very special

place. I wish you all the luck, and I hope the lava stays at a good,

safe distance. Thank you very much. Thank you. You're welcome. So it is

perhaps surprising that people like Robert choose to live in areas of

the world that are geologically volatile, and it's particularly, as

Ian explains now, because science absolutely knows where those areas

are and what makes them so I've come to the Bay of Naples to

see what is for me the most important Roman ruin in the whole

of Italy. There she is I know it doesn't seem like much just

sandwiched between all of these kind of modern apartments and

restaurants and right beside this busy road, but this - this is a

This is the Temple of Serepus. Just a stone's throw from the sea, it's

not actually a temple at all. It was a Roman marketplace built

around 2,000 years ago, but it's still kind of a demp for gee olss

because of this book, Charles Lyle's Principles of Geology. This

book is the cornerstone of modern geology.

And right here, embossed in gold on the front, the Temple of Serepus.

This place changed the way Lyle looked at the world, not because of

the ruins themselves but because of the tiny holes that pock mark the

three marble pillars. Crucially, he wreck niessed this as something you

commonly find on piers around here. It's formed by a kind of clam, a

tiny sea creature that nibbles its way into stone. He knew that the

Romans originally built a structure on dry land, but the holes in the

pillars meant it somehow got emerged in the sea only to rise

back up again. It convinced Lyle that the land was constantly moving,

constantly changing, and what's more is those processes are still

going on today. It can be observed all around us. That principle is

the foundation upon which modern geology rests. Today geologists

have a theory to explain Lyle's observations, the theory of plate

tectonics. Its surface is broken into lots of different pieces, like

a jigsaw, and those plates are constantly moving. The boundary

between two of the plates runs right the way through Italy. Here

in the Bay of Naples I am on the Eurasian plate which is more or

less stationary compared to the African one, which is to the north,

shunting into the Eurasian plate, so effect lively the two plates

have collided. Because the African plate is denser, it slides beneath

the Eurasian plate. This is known as subduction. This is the Eurasian

plate here, for an E. This is African plate that comes down and

subducts below it, so here's Africa. That's moving in that direction

there. As that slab descends deeper into the mantle, the temperatures

get hotter and the pressures get higher. Down there hundreds of

kilometres below the surface inside the plate and locked away in

minerals of the rock was water, water that under that hot, pressure

cooker environment gets forced out. The reason that's important is that

the water reduces the melting temperature of the mantle rocks

turning solid rock into magma, magma that pools and rises up

through cracks and fractures in the The Temple of Serepus and this area

is above the subducting plate. Beneath the ground lies a huge pool

of magma. You don't have to go far from the temple ruins to find

evidence of it. Just a kilometre down the road, hot gases seeping up

from below have created this alien landscape. The subduction of the

African plate beneath the Eurasian plate allowed magma to rise up

towards the surface. Now, huge quantity tease of magma have pulled

in a vast chamber just 10 dill meters beneath my feet. Gases paint

the rocks yellow. Water, that has been heated to boiling point under

ground, comes out as steam as the temperatures rises and falls the

land in this areas goes upwards and sinks back down. Over time the

Temple of Serepus, which was originally built on the shoreline,

has found itself submerged beneath the sea. The magma chamber beneath

the ground here is one string along this plate boundary. The same

subducting plate produces the magma that fuels all of Italy's famous

volcanoes like Etna and the others. Subducting plate boundaries like

this one are responsible for 80% of all the volcanoes on the planet.

Volcanoes are like beacons, marking out the places where these shifting

plates collide. They are not the only evidence that the surface of

our plan set constantly on the move. Plates are the ridgied skin of the

earth. The Terra firma on which we live. Because the plates are

constantly moving, when one continent-size slab of rock grinds

into another, tremendous pressure builds up. Enough pressure for that

crust to snap and break. When that happens, you get earthquakes.

Another earthquake has struck northern Italy killing at least 15

people and burying several others... Eight weeks ago, the same

subducting plate boundary, that produces Italy's volcanoes, caused

a series of lethal earthquakes. Over a year ago, subducting plates

beneath the Pacific Ocean caused the massive erk which in turn

triggered the Soviet Union that devastated the coast of Japan. 5%

of all the world's earthquakes are caused by subducting plate

boundaries. -- tsunami. It's driven by internal heat escaping from the

heat of the plan wet that comes earthquakes and volcanoes. There is

no Bert evidence that earth is a dynamic place, changing all the

time, sometimes violently. It may seem to us as humans the ground on

which we stand is fixed, but it's constantly on the move, just as

A point that comes out of that film, we have known for a couple of

centuries now the land moves in earthquakes and volcanos. We know

where the plates are. We have a map where the plates are. We have a map

here. You can see them there. What we can do, we can put all of the

known volcanoes, 1600 that erupted. It is obvious that the majority of

them run along coastlines. Along the coast of North America, South

America. Through the Med and the Ring of Fire. A lot of these

volcanoes are caused at the junction between the coast and the

oceans. That is where the ocean plates are sinking. Getting forced

under the continental ones. They are disappearing down there and

creating subduction own volcanoes. If we look at the maps. These

volcanoes have been active in the last 24-hours. They map really the

majority of them are in those subduction zones. These are the

nasty volcanoes, aren't they? They are the dangerous ones? The reason

for that is, the ocean plate, as it pushes down here, in the film I

explained how the magma melts, rises up and punctures through. As

it rises through the continent it picks up minerals that makes the

magma sticky. It traps gases which gather pressure, when they get to

the surface they explode out. Those are the real killers. The other

thing that causes us human beings to notice that our planet is as

dynamic as it is is earthquakes. Is there a correlation between

earthquakes and volcanoic explosion? Let's look at where the

latest earthquakes have been. These are all these green circles are all

the earthquakes that have happened in the last 24-hours that over 0.2?

The size of the circle relates to the side size. This is a 5.2 in

Papua New Guinea. Not very much for Papua New Guinea. If it happened in

Britain it would be one of our biggest one ever. Volumes come

along the plate boundaries. They related. If you think about the

population centres... Yes, scary. If you think about the number of

people who live along that coast of America, Southeast Asia in

particular. It's not just the people of Kalapana who insist on

coming back to a volume cannically active area, it seems to be

something that people the world over do. It was a couple of those

particularly densely populated areas in Southeast Asia and Japan

that were so devastatingly affected by the tsunamis in 2004 and 20111.

Ed Byrne went to investigate how an earthquake can trigger one of these

earthquake can trigger one of these deadly waves. Powerful earthquakes

and the immense tsunamis caused by them have killed over 800,000

people. An experiment has been set up to show how the build-up of

pressure is the primary cause between all earthquakes. These are

our tectonic plates then? plates are moving together against

each other. There is friction at their interface which is locking

them together. The stress builds over what can be decades or even

hundreds of years. As the energy increases and increases, hopefully

we will see the time of the earthquake. They just popped.

is the earthquake that happened. The energy that built up over

hundreds of years is released in seconds. That generates the seismic

wave that is cause earthquakes. That earthquake we demonstrated

there, what type would we call that? Subduction events. That

triggered the Indian tsunami. One plate can go below the other. They

enter lock. The top plate is being dragged down as well. When the

earthquake happens you have a spring back of the top plate, which

is causing the movement of water above that generates a tsunami.

2004 Boxing Day tsunami was formed 100 miles off the Indonesian coast

when a subduction earthquake triggered a massive displacement of

water above. It the wave travelled at the speed of a jet plane, but it

was a meter or so high. How did such a small wave turn into the

immense wall of water that killed so many people? I'm meeting Dr Adam

Crewe from Bristol University to find out. Tim will help us show

what happens when the tsunami hits the shoreline. Hello, Tim. It is

not that high. Come coming down. There it breaks. A massive amount

of money travelling at speed, what cause it is to break there on the

shore? We were moving so much water up there, very, very deep, deep

wave. It was going quite fast. As the waves get closer to the

shoreline, they start slowing down because the water gets shallower.

The front of the wave was slowing down, the back kept going, the

water builds up. The back of the wave catches up with the front of

the wave. As it gets high enough it starts breaking. Tsunamis are long

waves. Once you have them, the water hits the shoreline, it keeps

going. It does not act like a normal wave on the beach, it keeps

going and that is why they cause so much damage. I understand how a

subduction earthquake at sea can displace water and cause a tsunami.

What makes earthquakes so destructive on land? It is to do

with seismic waves. There are two different types of seismic wave

that are generated at the time of an earthquake. The first one, the

primary waves, travel like pulses in the ground, through compression

and they are very much like sound waves travel through the air. The

second type of wave travels side ways. Side to side movement causes

the way to go... Forward. Forward. That is right. Primary and

secondary waves bounce off or interact with the surface. They set

up new ways called surface waves, which are the one that is cause the

destruction. If I wanted to see the primary and secondary waves, and

the surface waves in action, where better than the country's biggest

earthquake simulator. Adam explains that one of the weigh ways to

measure the seismic wave is using magnitude scale like the Rickster

scale. The Rickster scale is surprisingly complicated, isn't it?

If you start at, for example, two then jump to three it's 30 times

more energy. 0 times more powerful the earthquake. When we go to four,

30 times more powerful. A magnitude four earthquake is 900 times

stronger than a two. That is headed close towards the six. That is what

they would get down in Greece, Portugal and Italy. They come

together to form these seismic surface waves. I have been

listening. On to the Japanese and How long would they normally last

in real-life? How long does an earthquake of this magnitude last?

Two or three minutes. Really? would keep seeing,away. That lasted

a minute. You could get three or four minutes of that. Today, I have

learnt earthquakes come in all shapes, sizes, colours and flavours.

Subduction faults under the sea can cause destructive tsunamis on land

it's seismic waves which do all the damage. Now, Hawaii sits slap bang

in the middle of the Pacific plate. Right in the middle is this set of

islands, in 1946, Halo suffered a tragic tsunami disaster. This is

the 1946 tsunami. You see the surge of water coming into the harbour

town. 96 people lost their lives. As often is the case, these

tragedies are the impetuous for doing something about it. I have Dr

Fryer from the Pacific tsunami warning system. What is the remit

of the organisation? Basically, we provide warnings, tsunami warnings,

to the entire Pacific and the Indian Ocean and the Caribbean. The

way we operate is, basically, we are looking for earthquakes. And,

the worldwide seismic graphic network we get all that data in

real time. So, we can issue a warning, within about 10 or 11

minutes of any earthquake anywhere in earth. The last big one was the

Japan one in 2011. You worked closely on that, haven't you?

That earthquake, we knew about it 40 seconds later, monitors in Japan

transferred to us. They got a warning out in 2 minutes and 40

seconds. The earthquake lasted three minutes. They under estimated

the magnitude of the earthquake which was part of their tragedy. We

took a little longer. We issued our warning at nine minutes. You have

footage of what that tsunami did. This is extraordinary. This is a

set of waves. The heights are here, a meter high. That was Japan. Here

are the Hawaii islands. We are now about six hours into it, the

tsunami hit the Hawaii islands at about seven hours. It went on. You

will notice behind the leading waves there are waves reflected so

the ocean is just Oz lating. It's a few tens of metres or a meter in

the ocean it's when it gets to the coast... The waves slow down in

shallow water, to carry the same amount of energy they have to grow

in height they will grow by a factor of four or five. It took 22

hours to get to South America. The waves are big. Southern Chile was

hit by waves 2.5 metres high. Significant damage. Boats were

carried into the town. Now, we see the tsunami getting through the

Drake Passage and into the South Atlantic. The waves are small.

Outside of Japan how many people were killed? The warning system

worked. Two deaths. A photographer who wanted a good picture. One

death the other side of the ocean in Papu in the Indonesian part of

What about Hawaii? Can it generate its own tsunamis? Yes, we have big

earthquakes in Hawaii because we have big volcanoes, and the

volcanoes are very large, very heavy, but weak. And they're

constantly collapsing and oozing out sideways, but they're also

being pushed. They have rift zones that fill up with magma, then exert

with outward pressure, so every once in awhile the whole of the

volcano will slip outwards 30 feet. The ocean gets pushed out of the

way. Presumably that doesn't give you a warning to issue. That's

right. The word around the Hawaiian islands is deep, so that means the

tsunami travels very fast. The last time something like this happened

was 1975. The epicentre was actually right at this spot. At

that time it took us an hour to get a warning out. Now we're down to 20

minutes. How about those subduction zone ones? How much warning do you

give for people to get off the beachs? For Hawaii, there are

sirens, and if we decide an earthquake is - provides a tsunami

hazard, then we just go off on the blower and say, "All counties sound

your sirens" and without question, they push their buttons. People

react accordingly, do they People on the big islands certainly will,

because they'll have felt the shaking. On the other islands,

they'll have probably felt shaking, but fortunately the sequence of

events that's happened in the recent past, everyone is educated

what to do. You know, Hawaii sits right in the middle of plate, but

it's along the edges of the plates where most of the geological action

occurs, so we went off to Iceland From above it's clear that

Iceland's landscape is scarred with great cracks and fissures, as if it

has been ripped apart like paper. Some cracks are several miles long

and added together, they form a huge rift, which crosses the entire

country. For millions of years, the North American plate has been

drifting westwards, while the Eurasian plate has been creeping to

the east, like two enormous conveyor belts moving in opposite

directions. These tectonic forces are tearing Iceland apart, and the

results of this monumental tug-of- war are clearly visible in the

landscape. As the plates pull apart, magma rises from the earth's mantle

to fill the gap, so wherever there are cracks in the crust, there are

volcanoes too, great long lines of them running along the central rift.

I've come to south-west Iceland to find out more about these great

tectonic features. For scientists like Bjorn Otson, studying active

volcanoes can be a dangerous job, but here, there's a unique

opportunity not just to get close to a volcano, but to go right

Mountaineers who are making final preparations for an extraordinary

descent, a real-life journey to the centre of the earth. They've rigged

up a mechanical lift, which will lower us directly into what was

once the fiery mouth of this volcano. It's a first for both of

us, and I, for one, am slightly apprehensive. Are you a little bit

nervous about this slightly Heath Robinson piece of kit that we're

descending into the bowels of the earth in? I think it will work.

hope so. I hope so too. Crossing over to the lift feels a bit like

walking plank, and the gaping hole beneath is impossible to ignore,

narrow bit here. It's a strange feeling, being

slowly swallowed up by the mouth of a volcano. It's a very kind of

organic feeling - space, this, isn't it? Yes. It feels almost

alive, the kind of shapes of the rock. It's just like it happened

yesterday. Yeah! You can see the bits of magma kind of left on the

side of the chamber. When it was plastered on the wall, it was not

fully solidified. So these sort of chocolate-like drips stuck to the

walls, that's the remnants of magma? Yes, the remnants. Gravity

pulls it down and it freezes. That's incredible. As we descend

further, the tube widens out, and we lose sight of the walls. We're

taller than St Paul's Cathedral. Powerful lights help to reveal the

huge space which is truly an extraordinary that I really wasn't

expecting - was the colour. It's just a riot of every colour you can

think of. That's true to the Icelandic mountains. They're built

up with many layers and many events of volcanic eruption, and we see

both ash and lava from different types of volcanic eruptions, so

this is like an open book. You can read the story of this mountain.

The red and orange rocks down here are all old lava flows from

different periods in the history of this fissure. As lava flowed to the

surface, layer after layer built up to create the mass of the volcano

above our heads. In the damp air of the cave, chemical reactions have

changed the colour of the rocks in those old lava flows, like the rust

it's important to remember the significance of this huge crack in

the earth. We're not only exploring the bowels of a volcano - this

place is part of a much bigger system. Most volcanic eruptions in

Iceland are on fissures, so Iceland is pulled apart, so this is the

centre, and on your one side, we see the North American plate. On

the other side, we see the Eurasian plate. So we're sort of standing in

the middle of those two tectonic plates? Yes, the two continents.

Does that mean effectively what we're doing is standing in a kind

of no-man's-land between the two? We're in Iceland! Good answer. It's

hard to predict which part of Iceland's rift will open up next.

But by studying these active zones, not only on the surface, but now

also within the fissure itself, Bjorn and his team stand to learn

much more about how Iceland's tectonic forces give birth to

do that, I thought she's just going to get into a big, black hole where

you can't see, but just looking at that film... You have gone slightly

green. I didn't think it was going to be - like you said... It was an

incredible experience. And it was just a really great way to

understand that formation of Iceland, so, you know, if we just

run through it again - you've got your North American plate and your

Eurasian plate. Will you be my plume for me? Yes. So you've got

the plume coming up, and that plume is basically creating Iceland.

there. But what's really interesting is, it was the exact

same process that also helped create some of the features that we

love in Britain because if we do it again - our North American - and -

this is the UK. Exactly. This is North America. That's the UK. If we

go back 55 million years ago, you don't have an Iceland. You don't

even have a North Atlantic ocean. The plume comes up - it breaks the

continent apart. You get a chain of volcanic centres, so you have

volcanic centres that are in Aaron, in Mull, in Sky. It's spewing out

the lava. The Giant's Causeway is one. Then what happens is that

plume kind of breaks it up... Pushes it apart. The ocean just

drifts apart, so that today North America is here. Britain is here.

So the plume is coming up here - that's where Iceland is. Could you

get to a point where Iceland stops effectively being the grout between

the two plates, and that then gets forced apart, and you get sort of

ice and land? Yeah, I guess. I think what'll happen is if the

plume starts to be less dynamic, then what'll happen is there will

be less material coming out, and you'll get a west and east

Iceland... That drifts apart. Hawaii is a bit of an anomaly then

- I said it! I can never say that word. It's not on plate boundary,

is it? No, but it's on a moving plate. One of the issues is you

have one plate and then one moving up. We have a Graf graphic that's

going to explain it. We have the plume coming up. It punches its way

through and creates this volcanic island. Because it's on the moving

plate it carries itself north- westwards on almost a conveyor belt,

and the magma is still coming up. So another new island pops up.

Create another new island. There we go. That's why when you look at the

Hawaiian archipelago it is a new line of islands. Exactly. It looks

like the checkout in the supermarket - the whole set of

things become a volcanic island. Eventually, we'll get a new island.

Hawaii will become inactive. So the one we're standing on will drift

north. We'll actually get a new island. The new Hawaii is over

there, so about 22 miles offshore, there is an island, which is only a

thousand metres - 3,000 feet below sea level. It's rising up. So if

anyone on Kalapana really want new land, hang around for tens of

thousands of years and occupy that one that pops up. Fascinating stuff.

The lava plume below Hawaii doesn't just create new islands. It moves

the earth in a way that scientists at the Volcano Observatory have to

be very busy indeed. My name is Weston, and I am the seismic

network manager here at the Hawaiian Volcano Observatory. I

study specifically earthquakes that Obviously, we've got a very active

volcano setting here. We have Kilauea that's active and has been

active for several decades. We've got Mauna Loa that isn't currently

erupting but has a long history of very frequent eruptions, so by

recording earthquakes, we can start to understand some of the process's

that are going on under the volcanoes. We start to forecast

volcanoes and when they might happen. What's really, really fun

is when you find something out about the volcano you didn't know

before. That's what I think I live for, and I think what a lot of the

scientists around here live for. Earthquakes that occur under

volcanoes occur from many different sources. You have magma moving from

shallow deep to the short part of the crust. As it moves up, it uses

fractures already existing in the crust, and those cracks or

fractures have walls on them that vibrate, and those vibrate much

like a piano string does, and that creates low-frequency earthquakes

that we see and typically look for before a volcanic eruption. So here

we have a seismometer. Essentially all it is made out of is a magnet,

and that magnet lies within a coil. When an earthquake passes by the

station, the seismometer here records that ground motion as a

voltage that is then being sent back to the digitiser and the

electronics box behind us. Around the island of Hawaii, we have

somewhere on the order of 70 stations, and we need a network in

order to record those so that we can surround the earthquake, and we

can triangulate and locate the earthquake and find out how big it

is. In 2011, the Samoamoa earthquake we saw an increase in

earthquakes and tremour, which you can see at the beginning where we

didn't have the eruption, there are no traces no, earthquakes. As we

move into the eruption, you can see the earthquakes - the vertical

lines here - are increasing quite dramatically. As they do, that is

an indication magma is on the move up to the shallow part of the crust,

and the location of these earthquakes tells us essentially

where that magma is moving from and to. That's kind of one of the

reasons why we all got into this field was to look for eruptions,

study eruptions, forecast eruptions Well, it's that connection between

earthquakes and volcanoes that actually leads us to our very first

viewer's question. You got in touch with us. I know some of you will be

shouting at the telly saying "it's not working". At the moment our

website is down. We are doing everything we can to get it back up

and running. Here we are. Our first question from Paul Metcalfe. A lot

of other people worried about their summer holidays. The Canary Islands.

There have been numerous quakes the island has apparently risen by nine

centimetres. Does that mean it will erupt? It has been going on since

late last year when it was predicted there will be renewed

activity. It has had quite a lot of activity. In the last few weeks it

has calmed down. That is why it's not on our map. It hasn't been

doing much. It's our closest active volcano. A lot of people go there

on holiday. We will be watching it. Is it a common occurance that it

looks like volcanoes will build up to an erruption and it fades away?

Yes. We can tell when the magma is coming up. What it will do when it

gets really close, will it burst out or sink back down? That is a

tricky one. There is another question, slightly connected to all

the things we have been talking about. We know why we don't have

volcano erruptions in Britain, but we do have earthquakes, why is

that? We do. We are sitting in the middle of a plate between Iceland

and Italy. The two places we have been doing our film. We have

passive. We have lots of faultlines, lines ever weakness. We used to be

right at plate boundaries. Those faultlines are places where stress

builds up and it gets released in earthquakes. The 5.2 one today will

be our biggest. We have a lovely question from Katri, who is six.

She wants to know why lav have is red? That is a good question. As

you heat something up it gives out light energy. If you want to see it.

Go to your oven, with your mum, she turns on the hob and it will go red.

When we have cool lava it's black. When you see it at night you

tkpwhaet wonderful red glow. I hope that answers your question. Owen

has another one. Owen will be here in two weeks. You can visit the

places we have been do. Why are crators almost always round? They

are explosive in one or two ways. From magma coming out, or because

the magma comes up, explodes out and collapses in. The same thing,

collapses in on itself. Broadly round. We have time for one more.

This has come in from Mrs Bell's Year 10 geography students. She

teaches in Norfolk. They all say - where are volcanoes called

"volcanoes"? It goes back to the Roman times actually. There is a

lovely volcano in Italy and it's perfect cone shape called volcan.

That is where they thought the God Volcan was. We stole it from Italy.

Someone saying we have one of those volcan's, you don't need to go to

Italy. Thank you for your questions. Tomorrow is our last show. Once the

website is up and running you can keep them coming in and you can

also tweet them. It is a constant frustration for volcanologist that

they can't go deep inside the volcano to collect the material

that would tell them all the answers to their questions about

their mist tierious inner workings. John Blundy who works at the

University of Bristol has discovered there is a particular

sort of rock that could answer the questions that keep him awake at

night. He went to the Caribbean to As a igneous petrologist, someone

who looks at molten rocks I work on the projects of volcanoic

erruptions I interrogate them to find out what happens before they

came out of the ground. A bit like a pathologist. I find rocks

fascinating. There is something about them that is really

tantalising. It's like a little puzzle that Mother Nature has

throne up -- thrown up. The challenge is to analyse the rocks.

I go with colleagues from Bristol University to do field work in the

Caribbean. In spring this year we went to Dominica, which is a lush

tropical rainforest. There are nine active volcanoes on Dominica, none

of them terribly well studied. There hasn't been a really big

erruption for about 1500 years. In the last year or so, there have

been a number of shallow earthquakes under the north of the

island, beneath the volcanic centre. The real objective was to

understand a little bit more about what goes on so we can understand

these earthquakes. We are here at the northern end of the island of

Domonica. I'm looking over the volcanic peak. If I was living in

these coastal villages here, or even in Portsmouth, beautiful

harbour to our left, I would want to know a bit more about the

volcano. The rocks we sample are like the witnesses to an event, in

this case the event is a volcanic erruption. As detectives want it

find the best possible witnesses, we want it find the best possible

rocks. This is really clear. A great sample. Sometimes if you are

really lucky, the volcano throws up bits of its guts. This is a cum lit.

It's a culmination of crystals deposited from magmas under the

ground. Each one represents a dissecret moment in the evolution

of the volcano. Within them there are clues there are -- to the past

history of the volcano. They're not very common. In some ways, it's a

bit like searching for gold or looking for diamonds. It's reward

if anything you find some, frustrating if you don't! -- you

find some, frustrating if you don't! The first couple of days we

didn't find any at all. We were also looking for volcanic rocks

themselves. Here is a bit of pumis. It's an air-filled rock. The

bubbles is where there was once volcanic gas. That expands and

pushes the magma out of the volcano. They contain crystals. I'm hoping

these are fresh. The compositions of the crystals can give us clues

as to where the magma was stored before the erruption. Which, in

turn, tells us where we ought to be looking for signs of unrest before

future volcanic erruptions. Day Three, we were now starting to feel

a little bit despondent about our failure to find any cumulates. We

got intelligence there had been a dam break a few years ago. A

natural dam had broken through and dumped an enormous volume of

material from the volcanic centres into the river. We set out to see

what we might find. Have I got a goodie for you? What have you got?

Yes! The river was flanked on either side by huge banks of gravel.

Because of the action of water, the gravel deposits were unusual rich,

it was a bonanza. This volcano really did spew its guts up. It's

exciting. It comes at the end of a couple of days of frustration. A

couple of days of thinking that, perhaps, it will not work out here

as it has on other islands. Dominica is the place to be. It's a

perfect spot for collecting these things. The work we do will

ultimately contribute to a better understanding of these volcanoes. I

think, volcanologists have a responsibility to do the best they

can to understand restless volcanoes because only through that

understanding can we be in a better position to anticipating and

mitigate volcano incidents and help people living in volcanoic areas.

They are really nice looking rocks as well! I have one of the rocks

here. It is lovely. This is like a forensic time capsule that allows

us to go into the depths and back in time. Jon Blundy will man our

web blog tomorrow night. Save up your difficult questions for him.

You can get us on at: It will get there. It is extraordinary really

that what we uncovered in the last hour is the fact that science has -

knows the planet quite well. We know where the at the time tonic

place are, the volcanoes and where we will get earthquakes. You look

at communities like this and you look at Kalapana, you can't help

celebrating the human spirit. Human beings do want to live in places

like this. The first thing is, this stuff is the way the planet works.

We have to get used to it. People do it for all sorts of reasons. For

the frontier spirit. For the human nature by now being cowed by the

volcano. It's our last programme tomorrow. We have lots of treats in

store. I go to Italy. Ed Byrne creates a super volcano with

plastic balls and a rubbish bin. go to the ends of the earth to