Fire and Brimstone!

Volcanic eruption

There’s something beautiful about a woman’s rage (not counting the tarts from Geordie Shore) and in no better way is this sentiment illustrated than by Mother Nature’s ire. As terrifying as it is to be at ground zero, from a safe distance, natural disasters are incredibly awe-inspiring and angry volcanoes deserve a top spot for making people go “ooooh” and “aaaaah” and “oh shit…”

Volcanoes are literal pathways from the Earth’s fiery guts to its crusty exterior. But the channels available for the molten rock and gas that spew forth are far too narrow to satisfy the sheer volume of indigestion within and the result is an immense build-up of pressure. The release of this pressure includes, but is not limited to, violent sprays of lava, devastating pyroclastic flows, stratospheric columns of volcanic ash, electrical storms, scalding gas and dust and Hiroshima-type explosions that not only dislocate millions of tonnes of solid rock, but have been reported to be audible many thousands of kilometres away from the point of origin.

Puyehue-volcano-eruption5

Puyehue eruption, Chile

Volcanoes have the potential to send species to extinction, yet at the very same time, they nourish the biosphere in an appreciable radius around them (volcanic ash is highly fertile). Volcanoes are magnificent and a wonderful example of how the surface of our planet is in a constant state of dynamism. 

Where Not To Go On Summer Vacation 

Computer-generated imagery depicting the perpetual convection of hot plumes of rock from the earth's core to its crust.

Volcanoes typically form at the convergent and divergent boundaries between the enormous shifting tectonic plates that comprise the Earth’s crust (see gorgeous image above). It is here that the seams of the Earth permit plumes of its molten interior to travel towards the surface. But as it was mentioned, the surface-bound transport of this material is anything but a six-lane highway. It’s more like a gravelly, pothole-ridden country road. The gas and molten rock that are trying to get from A to B encounter rigid rock and the cracks they exploit along their journey are incredibly narrow. A build-up of pressure results in a potentially explosive situation, so that when something finally gives, the results are disastrous for the local biology; human habitation included.

Volcanoes also form over features called “hot spots”, which don’t necessarily occur near plate tectonic boundaries (see diagram below). The Hawaiian Islands – all of them formed by volcanic activity in the middle of the Pacific Plate – are a prime example of this.

volcanic hot spots

There are several scientific theories that seek to explain what hot spots are and a popular one is that they are upwelling intrusions of molten material (mantle plumes) that originate at the boundary between the Earth’s core and mantle. The exact depth of this varies, but the Hawaiian hot spot is estimated to be 3,000 km deep. That’s 9,842,520 ft. for those of you in ‘Merica.

Volcano Classification

There’s more to volcanology than your stock standard angry Earth pimple. Volcanoes come in many shapes, sizes and compositions. What happens at the surface – what we see and experience when volcanoes awake from their slumber – is dependent on a suite of factors and an especially important one is the composition of the magma that is trying to escape the lithified constraints of the crust.

Lava Composition

Active-Volcano-lava flow

Rock that is rich in silicates tends to form chunky, viscous slow-moving magma. This subset of liquid rock is in no hurry to go anywhere and tends to contribute to terrible congestion. It also has the particularly nasty habit of trapping gas, which is why things can get explosive. Since Hawaii is no stranger to seismic activity, they have coined a word for this particular magma and it’s pāhoehoe.

At the other end of the spectrum, you get magma that doesn’t contain a lot of silicates, but is rather rich in ferrous compounds (iron). This magma – ʻAʻa, pronounced “ah ah” – get’s extremely hot and tends to flow hard and fast. If you’ll excuse the crass analogy, the difference between pāhoehoe and ʻAʻa is much like the difference between constipation and Delhi belly.

Both, however, are extremely uncomfortable.

Magma isn’t, of course, one or the other. There is a vast spectrum of mineral compositions between, but by understanding the difference between one extreme and the other, we can begin to understand how different kinds of volcanoes are formed.

Cone, Shield and Stratovolcanoes

If there’s one thing to be said for geologists, it’s that they don’t mess around with terminology. The name bestowed upon a volcano is as transparent as a wet T-shirt.

Cone (Cinder) Volcanoes 

Cinder, cone volcano

Lassen Volcanic National Park, California: A classic cinder or cone volcano

Cone volcanoes, also known as cinder cones, generally consist of a hill that can be anywhere from 30 meters (98 ft.) to 400 (1,312 ft.) meters in height. They are formed from the eruption of materials that are riddled with gas, crystals and a hodgepodge of fragmented rock. To see an example of this kind of volcano, put on your sombrero, crack open the tequila and get on a plane to New Mexico. There, you will find a spectacular volcanic field called Caja Del Rio, which comprises more than 60 cone volcanoes. If the prospect of New Mexico doesn’t appeal, you can always bum a lift on the next scientific mission to Mars or the moon, both of which are believed to feature this type of volcano.

Shield Volcanoes

Hawaiin shield volcano

Kohala Mountain, the oldest of Hawaii’s five volcanoes (Mauna Kea in the background). The entire island is a massive shield volcano.

Shield volcanoes have a much broader profile than cone volcanoes and, as the name suggests, are shaped like shields. Bet you didn’t see that one coming. These beasts are formed from the eruption of very runny lava that tends to escape the Earth’s crust before causing too much mayhem as a result of a build-up of pressure. Shield volcanoes are, by comparison, the placid elderly aunt of volcanoes and are most commonly found at oceanic tectonic boundaries. Oceanic plates aren’t usually rich in silicates, which explains why the magma produced here is more felsic in composition, hence its lower viscosity. Skjaldbreiður in Iceland (say that three times fast) is an example of a shield volcano. The Hawaiian Islands, which have formed almost smack bang in the middle of the Pacific Plate over a “hot spot,” are also shield volcanoes.

Stratovolcanoes 

strato-volcano_Composite volcano

Stratovolcanoes, or composite volcanoes, are the tri-polar member of the volcanic family. They look like your typical volcano but actually consist of alternating layers of different kinds of erupted material as the above diagram depicts. Stratovolcanoes produce a range of eruptions depending upon their mood and these include chunky cinders, choking ash and molten rock (lava). One of the best known (and least loved) of these volcanoes is Mount Vesuvius, which is located in Stromboli, Italy. This one was responsible for the notorious levelling of the cities of Pompeii and Herculaneum in AD 79, killing 16,000 people. It is estimated that Mount Vesuvius released 100,000 times the energy liberated by the Hiroshima bomb.

PHILIPPINES Mayon volcano in Albay

In June of this year (2013), the Mayon stratovolcano in Albay, Philippines, reached Level 1 alert level due to what the Philippine Institute of Volcanology and Seismology refers to as “abnormal behavior”.

Volcanic Hazards

volcanic eruption pyroclastic flow

Run?

When volcanoes become active, a number of things can happen, none of them good if you’re fond of life. One of the most devastating of these consequences is ash. You wouldn’t think so… ash is soft and white. How on Earth could it possibly inconvenience you the way a searing hot lake of lava might? Stratosvolcanoes are especially fond of explosive eruptions, which send voluminous clouds of ash into the atmosphere and cascading down their slopes. This ash, however, isn’t the kind you find in your barbeque pit after a night of camping, beer and sing-a-longs. It’s mixed with gas that is hot enough to disassociate your atoms. These eruptions send roiling clouds of gas, dust, ash and other debris down the mountain, which devastate anything organic in their path, leaving behind a scene that looks like a bomb went off in a cocaine factory.

Extinct, Dormant and Active Volcanoes: The Good, the Bad and the Ugly

Icelandic volcanic eruption

Icelandic volcanic eruption against a backdrop of the Aurora Borealis (Northern Lights) 

Volcanoes are dangerous creatures. So an apt analogy for the popular classifications of these geological features would be your mother. When she has a gin and tonic in her hand (dormant), you may want to make plans for the evening. When she’s 10 G&T’s down (active), it’s time to execute those plans and get the hell out of the house. When she’s passed out on the couch (extinct), it’s safe to come home, although my recommendation to you would be to move out and get yourself an education.

Extinct volcanoes, such as the Netherland’s Zuidwal and Shiprock volcanoes, are no longer considered to be active at all because they don’t have a supply of magma. They also have no documented history of indigestion. Dormant volcanoes, on the other hand, are known to have erupted at some stage in recent history. They may be quiet, but that doesn’t mean they can’t suddenly awaken. Mount Vesuvius (Gulf of Naples) was a purring kitten before it went psycho in AD 79, as was Mount Pinatubo (Philippines) prior to its epic tantrum in 1991. The latter is now considered an active volcano, which is one that has exhibited recent activity and is therefore a potential hazard to all within its vicinity.

The Ulawun Volcano in Papua New Guinea is an active volcano. Moreover, it has been classified as a “Decade Volcano”, which essentially means it’s one of the most dangerous volcanoes on Earth as far as potential damage to human habitation is concerned.

The Ulawun Volcano in Papua New Guinea is an active volcano. Moreover, it has been classified as a “Decade Volcano”, which essentially means it’s one of the most dangerous volcanoes on Earth as far as potential damage to human habitation is concerned.

Krakatoa 

Krakatoa Volcano 1883 eruption

If you’ve ever had a fight with Mexican food and lost (who hasn’t?) then integrating “Krakatoa” into your vocabulary is a wonderful idea if you need help explaining exactly what just happened to you to the flat mate who is next in line for the bathroom. You may not be absolved for your sins, but it’ll get you a laugh or two.

Krakatoa is a first class example of what happens when Mother Nature gets really cross and decides to let off a bomb that makes Hiroshima look like a fart. In 1883, the build-up of pressure under the Earth’s crust between the islands of Sumatra and Java in the Sunda Strait was so immense that it caused an apocalyptic-sized explosion, sending a once much bigger island into the stratosphere.

The Krakatoa eruption was reported to have been heard almost 5,000 km away (the loudest sound ever made in recorded history) and the resultant shock waves send barograph needles oscillating violently off the page. Over 36,000 people were killed by the eruption: if not by the devastating pyroclastic flows and falling debris, then by the tsunamis that followed. The dust catapulted into the atmosphere caused stunning sunsets around the world for months after the eruption. Too bad colour photography wasn’t in vogue in the 19th Century.

krakatoa - krakatau volcano map

A map of ex-Krakatoa and the now much smaller island of Anak Krakatau, which means “son of Krakatoa”. The dotted line represents the size of the island before it went nuclear.

Class Dismissed: Your Take-Home Message 

devastating lava flow active volcanoesIf you ever needed help respecting the fact that we are just not in control of our natural environment, then stand next to an active volcano. From lakes of lava and earthquakes that shake the foundations of your stick hut to falling debris and scalding hot pyroclastic flows that choke the biosphere: volcanoes are creatures to be respected, studied and understood. If ever there was an item to put on your bucket list, it would be to stand next to an active volcano and feel the heat of Earth’s interior lap at your cheeks. Just make sure you’ve ticked off the rest of those bucket list items before you do so… 

volcanic eruption from the air

This picture was snapped by a passenger on a plane bound for the Caribbean. It shows a colossal 12,000 meter-high (40,000 ft.) column of ash, gas and water vapor rising from the Soufriere Hills volcano on the island of Montserrat.

Plate Tectonics: The Ends (and Beginnings) of the Earth, PART 2

World's plate tectonics

Vector diagram indicating the Earth’s major tectonic plates, the boundaries between them and the direction of their motion. A vector is an arrow that physicists use to illustrate the direction AND relative speed of a moving body. I.e. the longer the arrow, the faster a plate moves.

Welcome back to this, the second instalment of our foray into the field of plate tectonics in which we seek to understand how the giant bumping and grinding shards of crust that make up the surface of our planet have helped to shape it, create it, destroy it and give Hollywood directors endless material for disaster movies. In Part 1, we began our journey with a look at convergent boundaries – where two tectonics plates come together causing a fender bender of such epic proportions that it has resulted in some of the highest (Himalayas) and deepest (Mariana’s Trench) topographical features on Earth.

We discussed the difference between continental collisions (where two continental plates crash into each other) and subduction zones (where one denser oceanic plate gets “pushed” underneath a lighter, crustier plate). Both are characterised by plates that are slowly, yet inexorably colliding into each other and both result in some totally awesome environmental features, such as soaring mountain ranges, plummeting ocean floors, city-shattering earthquakes and volcanoes with monstrous cases of indigestion.

explosive volcanic eruption

In this week’s blog, we’ll take a look at the other boundary types and what kind of geological party one might expect to find there…

2. Divergent Boundaries: When Two Plates Pull Apart

At the opposite end of a plate’s convergent boundary, one tends to find a divergent boundary. Here, the prodigious convection currents in the Earth’s asthenosphere (the squishy onion layer beneath the crusty lithosphere) serve to wrench the two plates apart. This exposes the bubbly mess of searing molten rock beneath. For the same reason you want to sew your butt cheeks together when you have a really bad case of “Delhi Belly”, this runny mess of lithic indigestion explodes out from between the plates causing all sort of fun for the neighbouring wildlife.

Plate tectonics, separation

Diagram illustrating what happens at a divergent pla…
Oh, Christ you’ve got eyes.

There are typically two geological features one finds at divergent plate boundaries and just as was the case with tectonic convergence, the resultant landscape depends very much on whether the plates pulling apart make up the continents or the ocean floor.

Mid-Oceanic Ridges 

mid-oceanic ridge

The Bold and Ridiculously defined Temporomandibularly Muscled

When the separation occurs between two oceanic plates, as is the case with the African and South American plate (in the southern Atlantic basin) and the Eurasian and North American plates (in the northern Atlantic basin), you get a mid-oceanic ridge, which doesn’t really look like Ronn Moss posing in the exquisite turquoise waters of some tropic paradise. No, mid-oceanic ridges are a lot bigger, a lot more ripped and far more complex, although perhaps not as emotionally so… and definitely not as annoyingly successful with the ladies.

mid-oceanic ridge tectonics

Whoar! Now that’s what I’m talking about! The Mid-Atlantic ridge in all its ripped glory. More fault lines than hairs on a manly Portuguese chest, more complex than your girlfriend at her best time of the month and more broodingly seismic than her temper after that fight you had when you commented on her Portuguese heritage.

Two plates can’t get away with divorce without some serious repercussions. For one, the divergent motion of the plates releases a whole lot of pressure on the underlying asthenosphere. It subsequently melts in relief, releasing a surface-bound flood of molten rock known as magma, or at least until it actually reaches the Earth’s surface, at which point it becomes known as lava.

Don’t ask me why geologists have to make things so complicated.

This lava cools and solidifies upon contact with the atmosphere or, in the case of mid-ocean ridges, the overlying water, forming blocky solid structures of igneous rock. Over time, the release of magma from the divergent motion of the plates forms wave after wave of new ground in a process referred to as “seafloor spreading”. This all explains why the age of the rock closest to a plate boundary is younger than the rock as little as 100 metres away! Cool, huh?

mid-oceanic ridge photo

Those bulbous rocky rocks are actually solidified magma (or lava) plumes, which have emerged from the depths of the central abyss.

Some of the attractions one might expect to see on a routine exploration of a mid-oceanic ridge include deep gorges and valleys and formidable submarine mountain ranges that are, in height, taller than Mount Everest. When you’re not “oohing” and “aahing” at the fantastic topography, you can “ugh” at the local wildlife.

pompeii-word-bristle-worms-alvinella-pompejana1

This sexy sock-face with nipples for eyes is actually a Deep-sea Pompeii worm, which typically hangs out near the hydrothermal vent chimneys found along marine divergent boundaries. This large sea squishy enjoys black smokers, long walks along the trench and its ambient environment close to boiling point. Hydrothermal Vent Eelpout fish, Giant Tubeworm and the Hydrothermal Squat Lobster are more examples of wildlife that find boiling water totally amenable. In fact, there is a whole community of specialised critters that have become adapted to life in close proximity to blistering, incandescent volcanic vents. 

Rift Valleys

When tectonic divergence occurs between two continental plates, rift valleys can form. East Africa provides us with a beautiful example of this in the shockingly named “East Africa Rift Valley.” I mean, how left field can you get? Here, the splitting apart of the Somalia and Arabian portion of the African plate has caused the ground to sink in a complex series of fault lines. The resultant synclines (fancy geology speak for “valley” or “dip”) can become filled with water, as is the case with Lake Malawi, Lake Tanganyika and Lake Victoria… some of the oldest, deepest and largest lakes in the world.

Lake Malawi_east african rift valley

A bird eye’s view of Lake Malawi: just one of the major bodies of water formed by the divergent motion of two Africa plates causing a physical cleft in the landscape.

“Hold on,” you say. You’ve referred back to the map of the world’s major tectonic plates and there isn’t a plate boundary anywhere near East Africa.

“How observant you are!” I exclaim saccharinely…

The Africa plate is in the process of splitting into two, like a giant amoeba or your mother’s personality when she drinks too much gin. The plate to the east of the Rift Valley is the Somali Plate and the one to the west is the Nubian or Arabian Plate (check out the diagram below). These two crusty offspring are referred to as “protoplates” or “subplates”.

east-african-rift-valley

What other exciting attractions do rift valleys have to offer us other than very old, very large and very deep lakes? Seismic activity of course, which includes all manner of fire, brimstone, earthquakes and highly specialized organisms that have adapted to the heat and the strange chemical environment found around aquatic volcanic vents.

3.    Transform Boundaries: Where Two Plates Rub Together

transform fault boundaryWe’ve looked at convergent and divergent plate boundaries, but what happens along the peripheries of the plate if the “front” is having a head-on collision and the “back” is being torn asunder?

If your guess was a great idea for a blue film, I commend you on your filthy mind. However, “transform fault” was more along the lines of what I looking for.

Transform boundaries are characterised by two plates grinding past each other. Since jagged rock rarely slides easily past jagged rock, this fault line tends to be the source of much rocking and rolling in the Earth’s crust. Every now and then – which is painfully slowly in geological time – one plate gets snagged on the other and they are brought to a strained halt. The pressure mounts as the one plate tries in vain to move on, but is held back emotionally by the other, until, in a sudden Earth-shattering shudder, they become unsnagged, sending the plates shooting past each other.

This is precisely why transform faults are notorious for causing earthquakes. One of the best-known examples of such a boundary is California’s San Andreas Fault (image below), which is currently – as we speak – being torn asunder by the divergent motion of the North American and Pacific plate.

San andreas transform fault

San Andreas transform fault, California

San Andreas fault is also testament to just how stupid humans can be… building a massive city on a fundamentally unstable Earth foundation is a disaster movie begging to be scripted and cast with slack-jawed hunky men and big-breasted, blue-eyed blondes. Although, if you are a film director and find yourself being inspired by this, please consider casting me as the clip-board wielding, surprisingly young, yet double PhD-educated science floozy! I may not have blonde hair, but you know what they say…

You can easily sleep with a blonde, but a brunette will keep you up all night long.

Mila Kunis is scientific evidence of this fact.

Mila Kunis

The disturbing reality about San Andreas fault is that it’s been 107 years since a major earthquake has occurred, which means that all these long years, the pressure between the plates has been building. Sure, there has been a smattering of decent earthquakes in between the 1906 San Francisco event and the present day – the most recent being the 6.0 magnitude Parkfield earthquake of 2004.

Don’t get me wrong, a 6.0 magnitude will leave your martini shaken and not stirred, but according to the latest Uniform California Earthquake Rupture Forecast (kind of like a weather forecast, but for earthquakes), California has a 99.7% chance of experiencing a larger than 6.7 magnitude earthquake in the next 30 years! I.e. you can bank on it.

It gets worse: the chance that this earthquake could achieve a magnitude of 7.5 or more is a frightening 46%. This may seem like a paltry percentage at first, but if your tandem buddy had to suddenly turned to you on a sky dive and tell you there was a 46% chance the parachute wouldn’t unfurl, you’d most definitely soil your undergarments. You can bank on that, too.

Could the next “Big One” finally send San Francisco into sliding into the sea? Is “Frisco” about to become the next city of Atlanta?

Who can say? Only time… and the underlying tectonic plates. Not Enya.

Massive damaging earthquakeClass Dismissed: Your Take-Home Message

Plate tectonics play an incredible large-scale role in shaping the surface of our planet. Of course there is a myriad of smaller scale (both spatially and temporally speaking) factors that mould the mountains you climb over, the oceans you swim across and the valleys you… bungee jump across?… to be with the one you love.

But, plate tectonics are the daddy of global scale change and transformation.

Be in awe!

Mila Kunis actress

So very in awe…

Plate Tectonics: The Ends (and Beginnings) of the Earth, Part 1

Earth from Space

Is it possible for something that’s spherical to have a physical end or beginning? A ball just keeps going on and on and on and on. No matter how many times you turn it, you never get to any definitive beginning or end. Where does an egg start and where does it end? With the chicken or the egg or the chicken or the egg or the chicken?

Chicken or the eggWell, in spite of its spherical shape, planet Earth has many beginnings and endings and they are found at the boundaries of the colossal shifting plates that comprise its surface! Plate tectonics account for many of the soaring and plummeting landscapes on our planet and it explains a host of our most frightening natural disasters, from spewing volcanoes to shuddering earthquakes. It builds beautiful fertile islands in the middle of vast ocean expanses while ripping the ocean floor apart elsewhere, forming trenches in excess of 10 kilometres deep. Understanding plate tectonics is key to understanding our planet and its dynamic surface, which, as stable as it seems under our feet, is in reality anything but. 

The Earth’s Surface is Divided into Plates

The Earth’s outermost crusty layer is known as the lithosphere (lithos meaning “stone” in Greek) and it can be likened to a giant shell that has been broken into large, rigid interlocking pieces (refer to the image below). These pieces sit upon the warmer and more malleable asthenosphere and basically bumble their time away by colliding into each other, pulling apart and rubbing against each other. They also, you know, support the entire biodiversity of planet Earth in their spare time.

Earth's plate tectonics

Meet Planet Earth’s tectonic plates: Americans and Canadians get the North American Plate, Europeans and Asians get the Eurasian Plate and the penguins get the Antarctic Plate… EVERYONE gets a plate!

The asthenosphere, which is fluid-like and warmer and more pliable than the outer crusty lithosphere, promotes the migration of the Earth’s tectonic plates. Prodigious convention currents of heat and molten magma travel from the bowels of the planet to its surface, compelling these giant puzzle pieces to move. Just like Tree Ents from “the Lord of the Rings” and the cogs in your brain after a heavy night out, these motions are frightfully slow. Some plate boundaries, such as the Mid-Atlantic Ridge, move as fast as your fingernails grow, which is approximately 1 to 4 cm per year. Doesn’t exactly make for riveting viewing, does it?

But over time, patience wins out against the resistance of solid rock and the results are as creative as they are destructive. 

The Three Plate Boundary Types

All of the plates that make up the lithosphere are in constant motion thanks to the giant hot and moist “visco-elastic” asthenosphere upon which they sit. Hot and moist. If you’ll refer back to the map above, you’ll notice that every plate fits snugly into another, much like a giant jigsaw puzzle. Since each plate is in constant motion, one can definitely assume that it’s where they meet – at the plate boundaries – where the party’s at.

The picture below shows us the direction of motion of each of Earth’s tectonic plates. At any given time, one periphery of a plate is wrenching away from another. At the opposite end of the plate, there is a violent collision going on, while the sides are causing iniquitous mayhem as they rub lasciviously against each other. And as the more, erm, experienced will know… friction leads to all sorts of seismic events.

Earth's plate tectonics 2

Map indicating the direction of motion of Earth’s tectonic plates. The red ‘teeth’ indicate where two plates are colliding, which, as we shall find out momentarily, has resulted in the formation of the magnificent Himalayan mountain range (continental collision) and Mariana’s trench (subduction zone). The first is home to the highest viewpoint on Earth (although you might kill yourself getting there) and the second, the very deepest point in Earth’s crust (although, again, you might kill yourself getting there). 

 1.    Convergent Boundaries: When Two Plates Collide

If you drove your car at the rate of fingernail growth into a brick wall, you would have no idea what would happen because you would have gotten out long ago to use the toilet and get married (probably in that order). But hypothetically speaking, in the absence of arseholes to use and arseholes to marry, you’d probably discover that nothing very much would happen in a collision between a brick wall and your car moving at the rate of fingernail growth. Why? Because you’re going too slowly!

BUT! Substitute your car with a billion tonne megalith and that brick wall would be cement dust in… oh a few million years or so!

The convergent boundaries of Earth’s plates result in the formation all sorts of interesting topographical features. Two colliding plates can either become a subduction zone (where one plate – usually the denser one – plummets beneath the other one), or it can become a collision zone. The plate boundaries that are home to continental soil tend to opt for the latter, while the plate boundaries that are home to ocean soil, the former.

Continental Collisions

Plate tectonics, collisionThe coolest example of a continental fender bender on Earth has got to be the Himalayan mountain range, which is home to the world’s highest, most hostile and most abundantly body-strewn slopes.  This formidable mountain range is the product of two continental tectonic plates (the Indian and Eurasian plate) crashing together and forcing each other to crumple and buckle into soaring mountain peaks and plummeting mountain valleys. There are more than 100 mountain peaks in the Himalayas that smash the 7,000 m (23,000 ft.) altitude mark. Mount Everest, the range’s and world’s largest mountain, comes in at 8,848 m… a staggering 29,029 ft. above sea level.

Himalayan Mountain RangeTypical and totally average view on a hike through the Himalayas

Subduction Zones

When two plates collide and the one happens to be heavier and denser than the other, it typically gets forced beneath the less dense plate. Imagine Paris Hilton gets into a fight with Natalie Portman. Who would come out on top? My vote would be on the substantially less dense (and Harvard degree-wielding) Miss Portman.

This kind of active plate boundary is known as a subduction zone and it can form deep-sea trenches that plunge for kilometres into the ocean floor, as well as yawningly vast abyssal plains that are home to a plethora of deep-sea squishies, only a fraction of which have had the pleasure of joining our taxonomy system. The remaining majority have not yet been discovered or named, although one did feature very briefly in the Pixar animated film, Finding Nemo.

Location of mariana trench map The vertical antithesis of the Himalayas is Mariana’s Trench, a deep gash in Earth’s crust in the Mid-Pacific, directly east of Southeast Asia (refer to the map above). Here, the Pacific plate smashes into the Philippine Sea Plate and the former, which is composed of denser, more metal-rich rock than the crusty, silty continental latter, gets forced downwards. There are examples of mid-ocean trenches all over the world, but at 11,000 m (36,070 ft.), Mariana’s Trench is the very deepest. Not even an inverted Mount Everest could fill this gash.

That is a huge gash. 

Marianas Trench depth reference

But wait, there’s more! One plate does not simply get sucked underneath another without the appropriate ceremony! Deep-sea trenches are very good and all, but we want fire and brimstone!

I’m so glad you asked…

The Ring of FIRE!

The ring of fire When one tectonic plate plummets beneath another, it faces the fiery wrath of the Earth’s immensely pressured mantle. This heat causes the hydrous (water-containing) minerals within the plate’s rock to release their moisture. Since water acts to lower the melting temperature, the mantle overlying the subducting plate melts (surprise!), sending plumes of magma towards the Earth’s surface.

Oceanic volcanism subduction These pockets of molten rock tend to become trapped underneath the crusty rock making up the lithosphere, where the pressure builds up. Eventually, all hell breaks loose and you get a volcanic eruption. This can occur either on the ocean floor or on land surface. Sub-aquatic volcanism tends to result in the formation of fiery, volcano-strewn islands, such as the Pacific Ring of Fire. Terrestrial volcanism tends to result in Pierce Brosnan being a hero and other awesome feats such as pyroclastic flows, earthquakes and village-bound lava lakes.

As long as the Earth’s tectonic plates are mobile, subduction will remain an ongoing process. The denser plate is continuously consumed by the continental plate, sending plume after plume of magma to the Earth’s surface, fuelling the ingoing wrath of these lithic pimples.

Stay Tuned for Part Two! 

Want to find out what happens when a billion billion tonne slab of rock rubs against another billion billion tonne slab of rock? Things get seismic.

Seismic events - Earthquake in Japan Stay tuned for next week’s blog instalment – Plate Tectonics: the Ends (and Beginnings) of the Earth, Part 2.

Titanium: An Excellent Metaphor for Emotional Resilience


Titanium_metal_2

What’s stronger than Roger Federer’s backhand, more durable than Celine Dion’s singing career and lighter weight than Kate Moss after a coke binge?

Titanium!

From NASA space shuttles to dental implants, this metal boasts a suite of impressive properties that makes it, quite literally, the most awesome metal on the planet and so very useful to mankind. In fact, many of our most important medical feats would not be possible without titanium.

Can you craft a functional tooth replacement from platinum? Nope! Can you make a space shuttle out of silver? You could, but it would be Challenger all over again. Could Venus Williams send a tennis ball into hyper drive with a tennis racket made of gold? With deltoids like that, probably… but that’s not the point.

Titanium is more than just a David Guetta song. Let’s take a closer look at this indispensable metal.

Titanium’s Many Claims to Fame

Space shuttle Columbia taking off

Space shuttle Columbia taking off

You cannot imagine a metal with more applications – important applications – than titanium. This lustrous metallic element is incredibly strong, lightweight, has a non-corrosive personality and enjoys long walks on the beach. A combination of these traits coupled with its low thermal conductivity (science speak for a high resistance to heat) makes titanium the perfect metal for the fabrication of totally awesome things like space shuttles, fighter jets, high performance cars, submarines and naval ships.

Powdered titanium burns brilliantly, so it’s used by pyrotechnics to make fireworks that don’t fizzle, but bang! It’s also used in sports where the weight of your tennis racket, lacrosse stick or golf club is as important, if not more so than its strength. Titanium, which is as strong as a steel alloy but 45% lighter, has the highest strength to weight ratio, so it achieves both. It’s no wonder the Russians clicked on to its incredible potential for military and naval applications, most notably for the building of submarines. And yes… the Russians beat the Americans to this one.

Mikhail Gorbachev Cold war Russian Leader_2

It’s in You

Usually, the special metals that are coveted by humans are rare. Or perhaps it’s because they’re rare that they’re coveted… but in titanium’s case, it is the 7th most abundant metal on the planet and the 9th most common element in the Earth’s crust. Just look at the ground beneath your feet. You are, unbeknownst, staring at this metal of which I so reverently speak. Touch yourself. Not there! There’s titanium in you too…

And that isn’t a metaphor for emotional resilience.

There’s titanium in meteorites, plants, on the moon and in the stars – our sun in particular – which is where this metal and the heavier elements that make up our universe are forged. There’s titanium everywhere and thank goodness for that, otherwise Venus Williams would long have long ago been kicked out of professional tennis for breaking so many rackets!

Venus williams throws a tantrum on court

The Name’s Bond… Biological Bond

Dental implant view on X-ray

Dental implant view on X-ray

One of titanium’s most interesting traits is that it is totally bio-compatible and that, if implanted in the body, will not be rejected by the tissue. In fact, bone readily bonds with the surface of titanium metal, as if it were just another part of your body and this is called ‘osseointegration.’ The ability of the bone tissue to biologically bond with titanium is what has made it an indispensable material in orthopedic surgery, where the repair of bones and replacement of joints is necessary.

It’s also what has made the entire field of dental implantology possible. In other words, without titanium, there would be no fixed and non-removable replacement solution to missing teeth. This would spell certain disaster for the human race, since we are so preoccupied with appearance. A lost tooth causing a conspicuous gaping hole in your smile would be the end of your sexual career.

old_person_missing_teeth

Forever.

Class Dismissed: Your Take-Home Message

Titanium is so strong, yet lightweight and so resistant to cracks, breaks, corrosion and fatigue that it’s used in some of the most demanding applications on Earth… in the fabrication of space shuttle that can safely tear through the thermosphere and in submarines that can plunge more than 3,000 feet deep into the inky blackness of the ocean.

Soviet submarine under water

Then there’s jewelry, professional sports equipment, pyrotechnics and dental implants, which can last more than 30 years embedded in the jaw of your mouth. We owe much of our medical and technological advancement to titanium.

Titanium’s abundance on Earth also holds for mankind an incredibly important lesson. To covet a resource just because it is rare is dangerous and the product of flawed thinking. Titanium is in great demand, not because it is rare (because it’s not), but because it has so many essential applications in the advancement of our civilization.

Now if only we regarded our natural environment with the same eyes.

Space shuttle take off and orbit

Space shuttle take-off!

Holy Hit!

If you’ve seen the movies Deep Impact, Armageddon, Asteroid or The Land Before Time, chances are you’ve entertained the idea: what would I do if a meteor was on a collision course with Earth? What would happen? Would NASA send out a space shuttle to intercept the galactic gate-crasher? Could Iran be coaxed into donating its alleged caches of nuclear warheads to the task of obliterating the Earth-bound asteroid? What’s the post-apocalyptic weather like? Will you need to pack an extra jersey?

All of these are important questions. But not all meteorite strikes need to result in global catastrophe, although the dinosaurs would beg to differ. Some are actually responsible for sculpting some of the most beautiful landscapes and fascinating geological features here on our planet and on every planet.

Meteors, Meteorites, Meteoroids, Asteroids, Comets, Shooting Stars… What’s the Difference?

There are more names for space-travelling rocks than Elizabeth Taylor had surnames. But there is a degree of difference between them that needs to be appreciated, whereas I’m sure that each of Ms Taylor’s successive marriages was just as dull as the last.

A Comet is (relative to a planet) a small chunk of dirty ice-clad rock that orbits the Sun: think Halley’s Comet or Comet McNaught. When it comes close enough to the sun, blasts of solar radiation send particles of ice streaming off its surface to form a long visible train called a ‘coma’.

Comet McNaught blazes a beautiful trail across a star-studded sky. The Milky Way is actually one of the spiral arms of our galaxy. You’re welcome.

An Asteroid is a small chunk of rock that is also in orbit around the sun. Only, asteroids are composed of rock, metal and sometimes even organic compounds. Not ice. As a result, they don’t get to wear a bridal train.

A Meteoroid is, relative to an asteroid, a much smaller chunk of rock. Where asteroids can be kilometres in diameter, meteoroids are no more than 10 meters across, although they can also be as a small as a pebble. Anything larger officially joins the terminological ranks of asteroids.

A Meteor is a meteoroid that has made it into Earth’s atmosphere and is visible to us humans. Remember that one sexy night you spent with that guy in his crappy car, staring up at the stars? Suddenly, there was a brilliant streak of light across the night sky, and then he looked deep into your eyes and said that it was a sign you’d be together forever. And then he dumped you the week after for some tart with bigger knockers.

Yes! A shooting star and a meteor are one and the same thing.

Quick, make a wish!

A Meteorite – this is where things start getting interesting – is also a meteoroid (c’mon keep up!) But a meteorite survives its entry into the Earth’s atmosphere and actually makes it all the way to the ground where it causes all sorts of inconveniences for the local biology.

Now, we know that our local biology has been inconvenienced on several occasions by rocks galavanting around the galaxy. But how come our moon is more pock-marked than a pubescent teen and we seem to be relatively unscathed? Where are the big impact craters on Earth?

Turns out, everywhere.

Earth’s Impact Craters

Barringer Crater, Arizona, USA. Formed 50,000 years ago.

The largest confirmed impact crater on Earth is right here in my own back yard in a small town called Vredefort, South Africa. This appreciable dent in our planet’s facade (a 300 kilometre-wide dent to be precise) was caused by a meteor impact that happened over two billion years ago. This impact crater, which is now a UNESCO World Heritage Site, is even bigger than the crater left by the dinosaur-demolishing Chicxulub asteroid.

Take that Mexico.

Arial view of the Vredefort impact crater, Free State, South Africa. Formed more than 2 billion years ago.

According to the Earth Impact Database, there are 21 confirmed impact craters in Africa, 3 in Antarctica, 18 in Asia, 26 in Australia, 37 in Europe, 8 in South America and 30 in North America (31 if you count Chicxulub off the Yucatán peninsula, but last I heard the U.S. wasn’t very welcoming of Mexicans.)

These are confirmed impact craters, which have met the rigorous qualification requirements laid out by the Earth Impact Database; our official scientific pageant for meteor-strikes (world peace is most certainly not one of them). If we were to consider the list of unconfirmed impact craters, these numbers would easily double.

So you see, unscathed we are not. Our planet is just as pock-marked as the moon. We just have the benefit of plate tectonics, wind erosion, water erosion and a biosphere to cover up evidence of our acne scarring.

Gosses Bluff, Northern Territory, Australia. Formed 142 million years ago.

Somewhere off the Yucatán Peninsula in a Galaxy Surprisingly Nearby

65 million years ago, a large extraterrestrial hunk of rock approximately ten kilometres (6.2 miles) in diameter raged into Earth’s atmosphere and smashed into the ocean off the Mexican coast. Sunbathing dinosauritas didn’t even have a chance to reattach their bikini tops before a shockwave so f&*king inconceivable in size and rage hit, I am forced by sheer necessity to use a curse word as an adjective to describe it.

“Within microseconds, an unimaginable explosion released as much energy as billions of Hiroshima bombs detonated simultaneously, creating a titanic fireball hotter than the Sun that vaporized the ocean and excavated a crater 180 kilometres (110 miles) across in the crust beneath. Shock waves blasted upwards, tearing the atmosphere apart and expelling over a hundred trillion tonnes of molten rock into space, later to fall across the globe. Almost immediately, an area bigger than Europe would have been flattened and scoured of virtually all life, while massive earthquakes rocked the planet. The atmosphere would have howled and screamed as hypercanes five times more powerful than the strongest hurricane ripped the landscape apart, joining forces with huge tsunamis to batter coastlines many thousands of kilometres distant.”

“A Guide to the End of the World”, Bill McGuire (2002)

The ‘Chicxulub’ impact was the catastrophic event that forced the extinction of much of Earth’s biology. The life that wasn’t instantly extinguished upon impact would die in the weeks and months of acid rain, falling debris, plummeting global temperatures, shuddering earthquakes, tempestuous weather and raging wildfires to follow.

Or in the subsequent years of icy nuclear winter.

Or in the years of solar radiation exposure caused by the Earth’s disintegrated ozone layer.

Yeah, sucked to be prehistoric.

Class Dismissed: Your Take-Home Message

(Really bad) diagram showing the orbits of known Earth-crossing asteroids. The four white dotted circles indicate the orbits of our solar system’s four inner planets, Mercury, Venus, Earth and Mars. The sun lies at the centre. In reality, this picture should be completely pink from the number of asteroids there truly are orbiting our sun. But Google wasn’t playing nice with me today.

Our universe, galaxy and solar system are swarming with lost and wandering bits of space rock. Some have managed to find a gravitational focal point to orbit around and we see these visitors from our vantage point here on Earth with accurate predictability. A perfect example would be Halley’s Comet, which we see once every 75, 76 years. Others wander our solar system far more eccentrically, although the gravitational pull of our Sun and planets do affect the path they travel.

The take-home message is that we, just like every other planet or moon in our solar system, are just as vulnerable to a catastrophic meteorite impact. We are not safe on our little blue planet. We have suffered in the past and we will suffer again in the future. Life here is precious. So make sure you appreciate it the way it is now, because tomorrow you might not have time to reattach your bikini top before a shockwave so f&*king inconceivable in size and rage hits, I will be forced by sheer necessity to use a curse word as an adjective to describe it.

… run?

A Glacier in Fast-Forward

Franz Josef Glacier as seen from the valley floor. This 12km-long glacier can be found on the west coast of New Zealand’s South Island, in the Westland Tai Poutini National Park.

 Ever wanted to see a glacier flowing in high speed? No? Never really thought about it? Yeah… me neither. And then I saw this video and it totally blew my mind…

The Six Most Awesome Rock Minerals (For Various Reasons) Part 2

The Naica Mine in Chihuahua, Mexico, is home to some of the largest selenite crystals (a variety of gypsum) in the world.

Welcome to the second instalment of this two-part blog series on the six most awesome rock minerals (for various reasons and in no particular order.) In the first instalment, we looked at iron pyrite for its wonderfully geometric crystals and diamond for its many different traits, not least of all its hardness and beauty. Lastly, the limelight was cast on fluorspar for its property of thermoluminescence, which is science speak for “going disco when thrown into a camp fire.”

We have three most awesome minerals yet to examine, but before I get cracking, I need to state that this selection doesn’t even scratch the surface of the sheer diversity of rock minerals, crystals and gems that are forged within the hot and pressurized interior of our planet. There are really so many rock minerals that are awesome:

  • Mica forms incredible flat sheets of translucent monoclinic crystals.
  • Amethyst derives its name from its ancient medicinal use as protection against poisoning and drunkenness (look how that turned out for the ancient Romans).
  • Calcite is special because it double refracts light and its crystals are perfectly-shaped 3D parallelograms.
  • Halite is special because it actually tastes like salt (formed from sodium chloride) and, if left undisturbed for many, many years, can form giant columns of glittering crystals, as we saw in that picture of the Chandelier Ballroom.
  • Corundum is awesome because it’s the second hardest substance on the planet and – contrary to its ‘tough as nails’ character – is formed in cute little pink hexagonal tubes. Like miniature pool noodles.

Then, there are all those minerals and elements we covet as rare, beautiful and valuable. My choice has been restricted to those that – while commonly found (as many of them are) – are still very special and frequently overlooked. The ones I have selected here are but a mere sampling, which has been done subjectively. Why? Because science. Oh and also; this is my blog and I’m the boss.

So… with that administration out the way, let’s don our hard hats, grab our picks and get excavating!

4. Obsidian

Chemical Composition: Silicon, magnesium, iron and oxygen
Why it makes this list: Its formation process is rad
Name Origin: “Obsius” after the Roman who apparently discovered this rock in Ethiopia.
Star Sign: Haha, just kidding!

Obsidian is a jet black stone with a vitreous (glassy) lustre. Just like glass, obsidian tends to shatter into sharp fragments when hit hard, although it is much stronger than the glass your beer bottle is made of, so smashing it against your head wouldn’t be advisable. Unless you’re the kind of person who would actually smash a beer bottle against your head, in which case: knock yourself out. Literally.

Obsidian’s strength and brittleness have resulted in its use as sharp cutting implements and weapons (spear and arrowheads), some of which date back as many as six million years. Ancient Egyptians found obsidian to offer a suitable artistic representation of the iris. As such, they would use it together with a variety of other coloured gemstones to recreate their dead or dying* pharaoh’s countenance on the front of their solid gold sarcophagi.

* Pharaohs spent more time, resources and effort planning their death than they did anything else. They believed that one’s mortal life was but mere preparation for the afterlife. Millions of years later – post science and technology – the majority of the world’s population still believes exactly the same thing.

King Tutankhamen was a tenderly young Egyptian pharaoh (he was 9 or 10 when he became king) who ruled during the 18th dynasty (1332 BC – 1323 BC). This mask was used to cover his mummified remains and contains inlays of, amongst other gemstones, serpentine, lapis lazuli, malachite, garnet and obsidian.

Uses aside, what I find to be most special about obsidian is the way it is formed and it is here that we encounter a very interesting geological pearl of wisdom. The longer magma or molten rock is allowed to cool for, the larger the crystal size of the resultant igneous rock. Makes sense doesn’t it? On the one end of the spectrum, we have granite, which is formed from the ultra slow cooling of magma over many millions of years. The next time you’re bonking your partner on the kitchen counter, take a brief look at the size of the crystals within its polished surface. Big, huh? Well, incidentally, so is the size of the crystals.

In this picture, we can quite easily discern between the three composite rock minerals that make up granite. The pink crystals are feldspar, the white ones are quartzite and the black is mica. Thanks ,Science Photo Library! You’ve just facilitated the education of those who don’t have granite kitchen counters to bonk on.

At the other end of the spectrum, magma that is shock-cooled doesn’t have any time to form crystals and the resultant rock is an amorphous lump of dark brittle glass. So, essentially, what you have just learned is that granite (as we can see in the above picture) is composed of exactly the same material as obsidian (as we can see in the picture below.) Yet they look completely different! It’s like that one Kardashian sister.

So… how can you shock-cool magma? The usual method employed by Mother Nature is ejecting it at a few hundred kilometres an hour out of an erupting volcano, at which stage it theoretically becomes known as lava. The molten rock cools from approximately 1000°C (1800°F) to a little over ambient air temperature in a matter of minutes. The result is obsidian.

The truth is, obsidian is not strictly speaking a rock mineral, just as granite cannot be considered a rock mineral. Remember our Spice Girl analogy in part 1? Well obsidian is a complex blend of all the rock minerals that make up granite (feldspar, quartz and mica). As such, obsidian is more correctly termed a “mineraloid.” If I was submitting this blog to my geology lecturer for marks, I would be penalized for lumping obsidian in the same category as iron pyrite, which is a true mineral. Then again, I would have long ago flunked that paper thanks to that terrible Spice Girl analogy…

5. Opal

Chemical Composition: Silicon, oxygen and good old H20.                                      Why it makes this list: Cos it’s so damn beautiful.                                                   Name Origin: From the Latin word opalus: “to see a change of colour”

If I was a Neanderthal (my mother will argue that I am) and you placed an uncut diamond and a stone of opal in front of me and asked me to choose one based solely upon its aesthetic appeal, I would point at the opal and say: “ug.”

You may snigger at my seemingly ignorant selection, but in addition to its superior aesthetics, high quality opal fetches as much as $20,000 a carat (about R80,000). This, my friends, beats the Chuck Norris of gem stones by a fair margin.

If you have ever closely scrutinized a piece of opal, you will know just how special it is and how very hard it is to explain its unique brand of beauty. Opal is composed of tiny spheres of silica (sand, essentially) which are packed into tight water-bound layers. Water does all sorts of strange things to light. Combine that with the near-translucent silica spheres and the incoming light gets so damn confused that is splits into all seven of its personalities. These bounce back and forth between the layers and eventually exit the stone to be perceived by our eyes. The larger the size of the silica spheres, the more colours we see, while smaller silica spheres tend to refract darker blues and violet.

I could bumble on about opal, but the truth is, this amorphous gem stone is just so pretty, only a picture could do it true justice:

Is it a kaleidoscope? Is it a laser light show? Am I on acid? No! It’s opal!

 6. Magnetite

Sorry, let’s try that again.

Chemical Composition: Iron and oxygen
Why it makes this list: It’s bipolar.
Name Origin: From the name of a Greek shepherd, Magnes, who discovered magnetite on Mount Ida when he noticed his metal-tipped staff sticking stubbornly to the ground under his feet.

We tend to think of magnets as man-made things, when in fact nature is simply bursting at the seams with examples of bi-polar oddities (we all know one). Magnetite, as its name suggests, is a black metallic rock mineral composed predominantly of iron and it is the most magnetic of all the naturally occurring rock minerals on our planet. Geologists frequently keep a lump of magnetite on their desks as a paper clip dispenser.

Magnetite does, of course, have greater claims to fame: its various properties provide scientists with an insight into fancy-sounding things such as plate tectonics, paleomagnetism and magnetohydrodynamics. I have chosen magnetite for this list because it blows my mind that a seemingly unremarkable rock dug up from the ground can make metal move of its own accord. Of course, it’s not really moving of its own accord, but everyone fantasizes about having telekinetic powers every now and then. Even if the object you’re manipulating is a paper clip.

Magneto, eat your heart out!

 Class Dismissed: Your Take-Home Message

There’s really only one message I want you to take home from today’s sciencey musings. And that is that even the merest glimpse beneath the surface of any scientific discipline reveals a fathomless volume of absolutely fascinating information about the world around us and, in the context of this article, beneath our feet. Every single gem stone scattered on the floor of Scratch Patch is special for many reasons that extend beyond their appearances, just like every single human being is. Unless you’re Paris Hilton.

Now, THAT’S hot.

The 6 Most Awesome Rock Minerals (For Various Reasons) Part 1

Geology is just one of the many scientific disciplines that have fascinated me over the years. As a teenager, I became fanatical about collecting rocks, rock minerals, crystals and fossils, every specimen of which I arranged fastidiously along the wall shelf that overlooked my desk (see photo below). I am proud to say that this extensive collection has been lovingly preserved in its original arrangement by my mother, starting with translucent colourless quartzite crystals, ranging right through the colours of the rainbow and ending with opaque, jet black fragments of obsidian. Dust and the occasional long-dead beetle aside, not a single rock has been discarded. They’re all there and they’re all special. I would like to extend a thank you to my mom for preserving my collection, although it wouldn’t hurt you to dust once in a while…

My personal collection of rocks, rock minerals, crystals, coral and fossils.

Collecting Rocks is Not Just for Boring People

Why on Earth would anyone collect rocks? Well, rocks tell us about the history of the ground underneath our feet and you don’t need to be terribly nerdy to appreciate that! Unfortunately, too large a percentage of that ground has been covered in concrete, ceramic tile, plush carpets and hardwood… or laminate if you’re a cheapskate. But beneath the man-made veneer of our planet lies a fabulous variety of rock types, minerals and crystals, each with a history; each with a unique set of properties; each comprising a piece of the puzzle that, once put together, tells the story of the formation of the Earth and how the land came to be shaped the way it is.

My deep interest in mineralogy and geology was and is about more than just the pretty appearance of certain rock minerals and crystals. It’s about their unique properties, characteristics and traits, a handful of which you will come to learn about in this two-part blog. Of the many rock minerals I have collected over the years – and encountered during GEO101 at university – there are some that have remained firmly lodged in my memory, just like pyroclasts in a volcanic breccia (geology metaphor FTW!) These are the rock minerals that, in my mind, are true testaments to the sheer awesomeness of the natural world.

And the Nominees Are…

Firstly, in the interests of scientific rigor, let me stipulate the following: this list is totally subjective, so forget the part about “scientific rigor.” The facts I present, however, are true! Secondly, my choice is restricted to rock minerals, or gemstones. Not rock types, such as marble, granite and shale. Minerals are the building blocks of rocks, just like desperate and marginally talented 20 to 30-something year old females are the building blocks of girl groups.

Granite, for example, generally consists of three different rock minerals: Scary Spice, Baby Spice, Fanta Pants and one that looks like a lesbian.

Hold on… I’m getting confused. That’s four spices.

Anyway, you get the point, so now that you know what a rock mineral is, let’s get to it! Get your De Beers on ‘cos we’re going digging!

1. Iron Pyrite

AKA: Fool’s Gold                                                                                                 Chemical Composition: Iron and sulphur                                                                   Why it makes this list: Iron pyrite crystals are one of the most incredible demonstrations of symmetry in nature.                                                                      Name Origin: Pyrite originates from the Greek word for “fire”

We tend to think of nature as being random and chaotic, but rock crystals are a beautiful example of how there is more flawless pattern and symmetry in nature than there is entropy and disorder. Iron pyrite is one of my favourite examples, with its brassy yellow crystals that are seemingly impossibly square in shape (or cubic as the geologists would say.) Pyrite frequently grows in great tangles of inter-grown geometric shapes, most commonly cubic and octahedral. The result is both incredibly beautiful and intriguing: something that could pass as the work of an abstract artist on acid.

Iron pyrite has been dubbed ‘fool’s gold’ owing to its glistening metallic yellow colour, which makes it look quite similar to – what else – gold; one of the most coveted elements on Earth. There are many differences between pyrite and gold, of course, but the most important to mankind is that iron pyrite is appallingly common and is likely to get an icy reception from your wife or girlfriend if given as a gift.

Then again, Jessica Simpson is living proof that you can be appallingly common and still be famous.

2. Diamond

AKA: A girl’s best friend.                                                                                     Chemical Composition: Carbon (and sometimes trace elements)                             Why it makes this list: Diamond doesn’t need an excuse to make this list.             Name Origin: Diamond comes from the Greek word adamas meaning “unconquerable” or “invincible.”

Diamond is the Chuck Norris of gemstones. It’s hard, it’s tough and it’ll charm the pants off any lady. Formed deep in the Earth’s crust under conditions of bone-pulverizing pressure and temperature, diamond is the hardest known substance in existence. And it wins this title by a very, very, very large margin.

When cut correctly, diamond’s reflective and refractive properties emit a kaleidoscopic disco of light, coruscating with every colour of the rainbow. Uncut, diamonds are translucent and have an almost greasy or soapy lustre; certainly not something one might describe as breathtakingly beautiful. Most ladies like it cut. Their diamonds too.

In addition to their aesthetic appeal, which has been adored and worshipped by cultures and civilizations across the world for centuries, diamonds also have rather useful modern applications. Actually, 80% of all the diamonds unearthed are exploited for their incredible strength as blades, grinders, bearings and drill bits. The other 20% are considered too pretty to be used for drilling open decayed teeth and so are square-cut or pear-shaped, these rocks don’t lose their shape DIAAAAMOOOOOONDS… *ahem*

There are many things that make diamonds exceptionally awesome: they’re the only gemstone composed of a single element (carbon), they’re the hardest substance known to man, they’re incredibly beautiful and they’re incredibly expensive. But the bottom line really is that diamond’s awesomeness transcends time, culture, civilization and class. Diamond is king (and a giiiiiiiiiiiiirl’s beeeeeeeeest frieeeeeeeeeeend!)

3. Fluorspar

AKA: Fluorite                                                                                                        Chemical Composition: Calcium and Fluorine                                                          Why it makes this list: For its, like, totally insane property, ‘thermoluminescence’. Name Origin: “Fluo” is the Latin word for “to flow.”

I first came across Fluorspar on a seven-day canoe trip down the Orange River, which is the natural border between South Africa and Namibia. On our fourth or fifth day, the guides pulled the canoes off the river onto Namibian shores and took the younger whipper-snappier of us on a gruelling 45-minute hike up the steep, boulder-strewn slopes. At the summit, we found an old abandoned fluorspar mine. There were just piles of this translucent green and purple mineral lying everywhere. So, we all filled our pockets and headed back down towards the camp.

That night, our chief guide showed us just why fluorspar was so damn cool. Onto the searing-hot coals that were the remainder of our nightly camp fire, he cast a handful of broken fluorspar shards and dust. After a few seconds, these rocks started to glow bright electric blue and green before shattering like popcorn into smaller fragments. In spite of the burning-hot bits of shrapnel that were sent whistling past our heads, we were enraptured by the performance and I have used fluorspar to impress girls ever since.

Unfortunately, I have run out of fluorspar.

Fortunately, I have my… personality to fall back on.

Fluorite is the trance partier of the mineral world

Fluorspar or Fluorite most commonly comes in cubic crystals, although the one’s we found on the Orange River had all been shattered or broken at some stage and so ranged in amorphous size. “Fluo” is the Latin word for “to flow” and was given to this rock mineral for its applications in iron smelting. In a peanut shell, Fluorite decreases the viscosity of molten iron, helping it to flow better.

It was only after the discovery and naming of fluorite that its awesome physical properties of fluorescence and thermoluminescence were discovered, which is incidentally where the word “fluorescence” comes from in the first place. Fluorescence – the emittance of that strange otherworldly light – is caused by the dancing of electrons within the mineral’s atomic structure. As they stomp around to the doef-doef music in their heads, they emit quanta of visible light that is most frequently blue in colour, but can be green, white, red, purple or yellow.

This is of course just an analogy. Don’t you dare write that down in your chemistry examination.

Coming on Monday: PART 2  

You may be bored at work, but you still have to do some, you know, work every now and then. To accommodate this, I have taken the liberty of dividing this post in two. Stay tuned for the second instalment on Monday in which we shall intrepidly explore the remaining three most awesome rock minerals! In the meantime, your homework is to ‘ooh’ and ‘aah’ at this picture…

The Chandelier Ballroom: A name deserved of this cavern, which can be found in the breath-taking Lechuguilla cave complex in New Mexico. Giant otherworldly fingers of glittering gypsum crystal formations reach down from the cave ceiling.

Life on Mars: Relocation, Relocation, Relocation!

Every single morning, when my alarm drops a hydrogen bomb into the middle of my sexy dreams, I lie in bed entertaining fantasies of further sleep. What would I do to be able to sink back into the cotton wool comfiness of my sub-consciousness for another half hour? In my irrational sleep-addled state, a lot! So, sign me up for the first commercial flight to Mars because with days that are not 30 minutes, but 40 minutes longer than on Earth, my desperate desire for extra sleep would be granted!

Curiosity Weighs 899 kg
Luckily There Aren’t Any Cats on Mars

On the 5th August this year (2012, in case you’ve been locked in a tower your entire life and are in dire need of a haircut), Mars rover ‘Curiosity’ made a successful landing on the powdery, rock-strewn surface of the Red Planet. A part of the Mars Science Laboratory (MSL) mission, ‘Curiosity’s primary objective is to explore the real estate on Mars and the possibility of humans inhabiting it at some time in the not-so distant future.

The Mars Rover, ‘Curiosity.’

This sophisticated piece of machinery (see above image) cost NASA $2.5 billion to build and is designed to investigate features of Mars’ geology and climate during the course of its two-year long investigation. More specifically, the aptly-named ‘Curiosity’ will be looking for “ancient organic compounds,” according to NASA Ames Research Centre’s planetary scientist, Carol Stoker. This would help us understand the history of Mars, Earth’s sister planet,’ as a previous or even current supporter of life.

All of the high tech gadgetry aboard ‘Curiosity’ is essentially geared at measuring the presence, nature and concentration of organic compounds that are possibly locked within the planet’s dry soils. After two years of exploration, ‘Curiosity’ will hopefully have been able to answer our many pressing questions about the habitability of Mars. This could bring us closer, much closer, to planning an alternate future on the Red Planet… just in case we gas ourselves out of our own home in the solar system.

Or, you know, in case Bruce Willis chickens out of his mission to blow up an Earth-bound asteroid.

Meet The Red Planet!

Hey, hi, how are ya?

Astute academics such as Dr. Richard Zurek, Chief Scientist in the Mars Program Office at NASA’s Jet Propulsion Laboratory (JPL), have strong reason to suspect that Mars was once home to some kind of living organisms and that the Curiosity mission will indeed yield fruits. The presence of frozen water at the poles, an atmosphere that consists almost entirely of carbon dioxide, geological features that appear to have been carved and shaped by running water and a climate that is not wholly intolerable, indicate that out of all other known planets and moons in our solar system, Mars is or at least was the most accommodating of life.

What we want to know is whether we too could one day inhabit this arid red landscape… and if so, what would life on Mars be like?

Planet Profile: Mars

What appears from space to be minor rippling in a crimson landscape are actually colossal mountain ranges, gaping chasms, impact craters and Martian rallies against occupation by Earthlings.

Etymology: Thanks to its blood-red colour, Mars was named by ancient civilizations after the Roman God of War.
Planet’s Diameter:  6,787 kilometres
Average distance from Sun: 227,936,640 kilometres.
Rotation period (length of day): 1.026 Earth days
Orbital period (length of year): 686.98 Earth days
Menstrual period: huh?
Tilt of axis: 25° (Earth’s is approximately 23.4°)
Maximum surface temperature (tanning weather): 37°C
Minimum surface temperature (cuddle weather): -123°C
Best view from Mars: Olympus Mons, which is 27 kilometres higher than surrounding lava plains.
Atmospheric constituents: (1) 95% carbon dioxide, (2) 3% nitrogen, (3) 1.6% argon and (4) other trace gases.

Your Martian Calendar and Climate

Because of Mars’ distance from the sun, 227,936,640 km on average, it takes quite a bit longer for it to bumble its way around the fiery focal point of our solar system. This means that a Martian year is much longer than an Earth year; approximately twice as long, in fact. There are 687 days in a year on Mars. Thanks to the planet’s tilted axis, however, there are still two primary seasons: summer and winter. This doesn’t really matter though. With average year-round temperatures of -60°C (-80°F) you’re still going to need to take a very warm jacket and maybe a pair of mittens, too. There are a few balmy days to look forward to… in summer, the mercury in Mars’ equatorial regions can actually hit 20°C (70°F), punctuated by days of a roasty toasty 37°C (98°F), which is more than I can say for this God-forsaken winter we’re having here in Cape Town.

In spite of the cold, Mars is a desert planet, much like Tatooine, the one Star Wars’ Anakin Skywalker comes from… wait, hold on… did I just say that out loud? It never rains on Mars’ rust-red landscape and the only break you get in the distant and diluted sunshine is high level, coruscating congregations of ice-crystals; similar in fact to the cirrus clouds we get here on Earth. Bitterly cold winters aside, Mars would seem to be a rather affable place to settle.

Wouldn’t it?

Not always! When the horizon darkens and the wind picks up, it’s time to hit to road, Jack. Mars’ raging dust storms are the most tempestuous in the entire solar system.

In 2001, the Hubble Space Telescope captured the complete transformation of Mars as an enormous dust storm swept over the entire globe’s surface. These storms are driven by winds of up to 160 km/hr and can last weeks or even months. On the up-side, with nothing else to do, this would hurry along the repopulation of Mars…

Martian Tourist Attractions

Once you get bored of admiring endless vistas of red nothingness and of tripping over the legions of sharp rocks that are ubiquitous to Mar’s dusty, empty landscape, you will need to take in a few of the planet’s more redeeming features. Thankfully, there are plenty of those. Mars offers some spectacular natural attractions that make the Grand Canyon look like a butt crack and Earth’s biggest volcano, Mauna Loa, look like a bug bite. Albeit a bad one.

Olympus Mons is Mars’ largest mountain/volcano/OMG-look-at-THAT!! At a lofty 27 kilometres (17 miles) high and an expansive 600 kilometres (372 miles) across, this megalith is three times as tall as Mount Everest, Earth’s largest mountain. It’s also the largest known volcano in the solar system.

What was once a suppurating abscess of death is now a brooding black-head on the face of Mars’ blood-red landscape. Olympus Mons sits conspicuously in the top-right hand quadrant of this Google image of The Red Planet.
A height scale has been used in this rendering. White and grey represent heights of over 10km, yellow represents ancient sea level (0 km) and surfaces coloured blue, green and black are believed to have once been vast deep-sea abyssal plains.

You might also like to include the Valles Marineris canyon network in your travel itinerary (see image below). At its deepest, this great cleft in Mars’ crust plummets a dizzying 10 kilometres (6 miles) and stretches in the vertical for 4,000 kilometres (2,500 miles).

The Valles Marineris canyon network

Then there’s Mars’ pock-marked landscape to explore. Since craters – evidence of meteorite strikes – are quickly eroded away or overgrown with vegetation here on Earth, Hellas Planitia, Mars’ largest impact crater, would be an especially novel sight for us Earthlings. Oh! It’s 2,300 kilometres (1,400 miles) wide.

The Hellas Planitia impact crater

Mars boasts more than just these mega geological features to “ooh” and “aah” at. There’s the gorgeous orange sky and blue sunsets to admire! And if you ever get tired of staring a red landscapes, you can always pack up your skis and go on holiday to the polar ice caps. This is greatly recommended in winter when Mars’ frosted latitudinal extremities become covered with an additional layer of ice composed of carbon dioxide, AKA dry ice: the most fun thing to play with in the universe!

Okay… the second most fun.

Last, but certainly not least, Mars tourists will be staying up past bed time to admire the night time sky. The Red Planet has two moons called Deimos and Phobos. Their sinister names mean ‘panic’ and ‘fear’ respectively, but don’t count on any travel agents telling you that.

Er, Minor ‘Challenges’

Life on Mars would be rad and wholly different. The scenery might get a bit samey after a while, but with a bit of ingenious technology, we could definitely make it habitable. There are, however, some challenges one should be prepared to meet:

1. Sub-zero temperatures most of the year. 2. Dust everywhere. 3. Sun burn: Mars doesn’t have a magnetic field to deflect incoming solar radiation. Without a special suit, you’d blend right into the landscape after a few minutes. 4. Dust, like, everywhere. 5. No 7/11’s or Wal-Marts 6. Difficulty looking cool in front of your cherry: Mars is littered with rocks just waiting to trip you up. Worst of all, when you do trip up, the planet’s low gravity will make you fall on your guava in slow motion. 7. Giant raging dust storms that last for months. 8. Dust in your underpants 9. Dust 10. Dusty dust

On the upside, no matter how fat you are, you’d still weigh less on Mars because of its weaker gravity. This also means that our primary mode of transport could be gummy-bear bouncing. Here and there and everywhere.

The winner for best Google search image in the category “bouncing gummy bears” goes to…

Class Dismissed: Your Take-Home Message

Life on Mars is a very real possibility. The biggest challenges we would face in a move to colonize our sister planet would be getting the incredible amounts of equipment we need there and establishing a self-sustaining station complete with a renewable source of water and oxygen. But before you start saving your pennies to book yourself a place amongst Mars’ first human inhabitants, let’s not forget just how lucky we are to have the planet we’re standing on. Earth, our Blue Planet. Two thirds of its surface is covered in water, its atmosphere is rich in oxygen and it is the most interesting and biologically diverse planet in the solar system, possibly even the galaxy and maybe even the Universe.

Let’s try to keep it that way.

Home, sweet home! Oh wait, isn’t that a… hurricane?