Category Archives: Earth and Space

Colour the Ocean

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Maldives

Oceans are full of colourful biodiversity. After all, we are the blue planet in our solar system, that we ironically call Earth. Oceans cover more than 70% of our planet, and at least as many species that live on land. Most of us see this magnificent beauty through the medium of documentaries, books and the Internet, and for the super keen, through the actual experience of scuba diving itself. Marine scientists have the excitement of many more discoveries to be made about the biodiversity that lives in this underwater world. And yet, human activities are rapidly affecting both the quality and quantity of marine life through overexploitation of fishing, oil seismic exploration and tourism to name a few. As global warming continues, ocean acidification will continue to adversely affect marine life.

As a student activity, selecting a range of marine species to draw encourages further learning and reflection of their current state of beauty and to appreciate what could be lost. Through enhancing scientific visual literacy skills, marine illustrations aid in the visual impact of scientific information. I have drawn a range of illustrations both above and below, with the intent that they can be coloured in, combining science and art skills.

Ecotourism Challenges

I can recall memories of swimming in Waikiki beach in Hawaii, surrounded all too frequently by rubbish. A dashing visit to the Maldives shocked me more by rubbish lying about the shorelines of the capital, Male Island. Resorts and beach villas have transformed coral reef and atoll ecosystems. Swimming in the Galapagos Islands I discovered a lack of colourful coral reefs and fish to be seen, although strict regulated tourism procedures were evident. Coral reefs have a high degree of biological diversity concentrated in a small area, and are sometimes referred to as the rainforests of the oceans. Coral reef systems are also incredibly vulnerable to destruction, as they grow slowly and are sensitive to changes such as rising seawater and increasing temperatures.

Ocean Noise

Our ocean is a symphony, where marine species such as the whales and dolphins communicate and navigate over vast distances. Sound travels considerably much further distances than through the atmosphere. Sonic sea, a documentary shown recently at the science festival in Dunedin, explored how human activities are adversely affecting marine wildlife. It really is alarming at the distress marine life is being subjected to, many of these larger marine species having grown up in much quieter oceans. Whales are more frequently beaching themselves as a consequence. Noise pollution, overfishing, oil drilling and ocean acidification are some reasons for our wildlife being adversely affected. The big question here is what are we prepared to do about it – to maintain biodiversity and colour in our oceans.

 

 

 

Weather and Weathering

 

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Glacier Perito Moreno, Argentina

Rivers of ice have always fascinated me. Ice ages have been greatly influenced by Earth’s climate over the past three billion years, if not longer. Various theories suggest that processes such as tectonic uplift and rock weathering, sunspot activity and orbital variations have all impacted on climatic conditions and glaciations. Despite the threats of global warming, we are still in a glacial period – the icecaps in Antarctica and Greenland show us this.

Climate Change

A significant component of the Earth and Space curriculum addresses the understanding of climate and weather, the most recent controversies being that of climate change. Recently Tim Flannery, a professor at Macquarie University and Chief Commissioner of the Climate Commission in Australia has spoken at the Regent Theatre in Dunedin on his latest research and thoughts. Professor Flannery was named Australian of the Year in 2007, and has spoken and written books related to climate change. It is widely accepted that human activity is accelerating the pace in which the environment can adapt, environmental consequences that may frighten us in years to come. He has had some interesting concepts in recent years – initially supporting nuclear power and then opposing the idea in Australia. He also suggested the release of more sulphur into the atmosphere to block the effect of solar energy and to enhance global dimming. With global warming expected to occur in the future, glaciers will continue to melt and sea levels rise.

Weathering

So what is weathering? It is the break down of exposed rocks that are transported as smaller fragments of rock and minerals. Gravity, wind, ice and water are various ways that rock is transported depending on how big the particles are and how strong the erosional force is. There are different ways in which rocks can be weathered. Biological weathering involves the breakdown of rock due to an organism’s activity, such as bacteria, worms burrowing or growth of tree roots. Physical weathering is the most common for glaciers and generally involves water and changing temperatures. Freeze thaw action will eventually spilt rocks as the water freezes and then thaws in cracks. Rocks are a mixture of different minerals, which also expand and contract to varying degrees when they warm up and cool down.

Chemical weathering occurs largely through acid rain. All rainwater is slightly acidic, as carbon dioxide from the atmosphere has been dissolved into the water droplets. However pollutant gases also dissolve in raindrops further intensifying the acidic levels. Acid rain has a significant effect on marble, which is essential limestone metamorphosed. India’s Taj Mahal in India built during the 1600’s is being significantly damaged by acid rain and has now lost is brilliant white lustre. The Acropolis in Athens was built further back in time over 400 years BC. However heavy vehicle emissions and pollutants from a congested city has contributed to the acid rain in the region. Even low levels of acid rain are having an impact on the marble surface and degradation.

Glacial Erosion, Chile and Argentina

Reaching to high altitudes involves colder climates and seeing a landscape of snow and ice. I’ve had my fair share of fun and challenges climbing through the Himalayas and volcanoes in Africa, Chile and Iceland. Glaciers are referred to as icy rivers. They flow very slowly, on average around two metres a day from the ice caps. With the tonnes of weight of ice, glaciers carve out U shape valleys with steep slides and flat valley bottoms. Moraine of rocks accumulates to the side and at the end (snout) of glaciers. Many glaciers end in oceans or lakes, as I saw in Chile and Argentina.

Perito Moreno Glacier in Los Glaciares National Park, Argentina is around 30km in length and is fed by the Southern Patagonian Ice Field located in the Andes. It was magical to see continuous ice breaking away from the glacier and crashing into the Argentino Lake. It is easy to assume this glacier is retreating – in fact it may be slightly growing, although glaciologists often debate this.

Mount Everest Nepal

Khumbu Icefall at the head of the Khumbu Glacier not far from Everest Base Camp is deemed incredibly dangerous, almost suicidal. Particularly as the sun warms up the ice in the morning, moving large crevasses open with very little warning. I witnessed large blocks of ice crashing down – I first heard what sounded like a clap of thunder before I saw the ice and then dusting of snow settling. It’s a gruesome thought that not everybody that dies in his or her pursuit to summit Mount Everest can be recovered. I was told by my guide that bodies that die in the Khumbu Icefall are often found years later as the ice moves with gravity towards Everest Base Camp. Sherpa, which is a recent documentary illustrates the dangers of the Khumbu Glacier Icefall and the detrimental repercussions within the Sherpa community. In fact it is quite a controversy, driven by a deep respect for the mountain gods.

 

 

Extremes Environments

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Liwa, United Arab Emirates

Unusual rock landscapes are distinctive. Bizarre rock formations are twisted and contorted depicting an ancient story of thousands of years of erosion by wind and water. Memories from seeing some of the vast and unique formations in Bolivia inspired thoughts of how weathering and geological processes have sculptured such beauty. It was rock art. Rock Tree (Arbol de Piedra) in Bolivia looked as real as what I had seen in the photographs. True to its name, it indeed looked like a tree and incredibly top heavy. It’s only matter a time before it topples. Geological time.

Desert Landscapes

Deserts are such a different, distinct landscape. Beautiful in their simplicity with sand sculptured sand dunes and the occasional enchantment of an oasis. But not all deserts are sandy; some can be rocky, stony or even icy like Antarctica.

Deserts are dry, rainfall is rarely seen – in fact certain areas of the Atacama Desert has not felt raindrops for hundreds of years. Even though temperatures may scorch during the day, deserts are often cold at night. The Atacama Desert in Chile rarely sees any rain as most of the moisture from the air is squeezed out as it passes over the Andes. It has been recorded as the driest non-polar desert in the world consisting of a stony, sandy and salty landscape. A variety of flora and fauna has evolved in this ecosystem, typically found closer to the coastline. I explored Valle de la Luna (Valley of the Moon), relishing in a unique landscape of sand and rock formations, carved by wind and water.

Some incredible plants and animals have evolved to live in harsh desert conditions with unique adaptations. Arabian Camels can store food in their humps and do not need to eat for weeks, or drink for days. Camels often travel in groups; I was lucky to see a herd of wild camels zigzagging their way through the Arabian sands between the UAE and Oman.

The Arabian Oryx is a medium-sized antelope with distinctive long straight horns. They escape the heat of the day by seeking shade and are able to detect fresh plant growth from a distance. Oryx leucoryx has been classified as endangered species and was extinct in the wild by the early 1970’s. Thanks to the scientific investment in zoos and private reserves it has made a comeback and was reintroduced into the wild from 1980. The Arabian Oryx is the national animal in a number of Middle Eastern counties, including  the UAE, Jordan, Oman, Bahrain and Qatar.

Cacti have evolved sharp spines from leaves to minimize water loss through transpiration alongside providing a sharp defense against predators. Joshua trees in the Mojave Desert in the USA take many different forms, sometimes appearing full and bushy, and other times spindly and sparse. Yucca brevifolia survival is a fine art – waiting for the arrival of well-timed rains and pollination from the Yucca moth. Many animals, birds and reptiles rejoice in the Joshua tree for food and shelter. With the comfort of travelling through the Mojave Desert in a car I could simply enjoy their artistic shapes and sizes.

Salt Landscapes

It is surprising to find any kind of life in the most hostile of environments. I have visited Death Valley National Park in the USA, where the hottest temperatures have been recorded in the world. It is the driest and lowest spot in North America, -86 metres (-282 feet) below sea level.

Visiting the Dead Sea on the border between Jordan and Israel created a headache for me. Literally! Between dehydration and atmospheric pressures of being – 414 metres (-1360 feet) below sea level. Both landscapes are marked with an abundance of sodium chloride. Very few plants and animals can survive the salt flats. The Dead Sea is also referred to as the Salt Sea, with high concentrations of salinity at around 32%. At the very least, the sensation of floating due the natural buoyancy makes for a memorable experience.

 

Uyuni is located in the south west of Bolivia and is famous for Salar de Uyuni. It is the world’s largest salt flat in the world, but this time at greater heights of 3656 metres (nearly 12000 feet) above sea level on the Altiplano plateau. Formed from a prehistoric lake around 40,000 years ago, today the large expanse of salt can be up to 11 metres thick. The region is also rich in lithium reserves, containing over half the world’s reserves. The day I visited, I did not see any form of wildlife, although cacti (Trichocereus pasacana) can be seen on Incahuasi Island . This island is a remnant of an ancient volcano, which was submerged in a prehistoric lake. Deposits consisting of fossils and algae have also been found. Looking around at the largest salt plain in the world made me question how I could survive in such a habitat. Not very well – it was hot, dry and barren. It was beautiful but deathly.

Earth’s Romantic Past

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Welterbe Grube Messel Pit, Germany

Let’s mix up some ‘Cenozoic’ for a little adventure. Making fossils is not only fun but also a creative way for kids to learn about paleontology. A dash of plaster, paper cups and various objects, paints and colour pens does the trick. I find students have a particular fascination with fossils and exploring Earth’s species that have been and gone. In keeping with the Earth and Space science curriculum, there is a teaching unit related to dating geological events. From radiometric dating, fossils, erosion, tree rings and even volcanic events, various scientific methods and philosophies can be explored to stimulate thought and research.

Portrait of our Planet

The cover story this month in the New Scientist Magazine outlines a beautiful article on evolution and the future of species – 7 billion years from now. Some may regard it as being alarmist – but at the very least it makes you reflect on the future of our planet. What will Earth’s final chapters of life illustrate? Planet Earth is approximately 4.6 billion years old and the evolution of life has come a long way in that time. But what will the future behold – it’s quite hard to imagine? Will life revert to the beginnings of when Earth first formed, with species diminishing in numbers and size? How will species adapt, migrate and evolve? An educated guess can only but hypothesise bizarre life forms that may emerge. James Lovelock, best known for his Gaia hypothesis is convincing in his argument that it is the biosphere that greatly affects the chemistry of the Earth’s surface, including oceans and the atmosphere. The Metaphor of Gaia has been an inspiration for scientific enquiry, given the complexity to prove the hypothesis with current scientific methodologies. But Earth’s processes are also in the game as plate tectonics transform the geosphere and consequentially the biosphere’s fate.

And what is the fate of human life? The fossil record does not inspire the greatest confidence in the future of mankind. Mammal species survive approximately one million years on average. So far, humans have existed for 200,000 years. How will we survive threats from disease, climate change, ecological degradation and natural disasters? Is it a matter of Homo sapiens evolving into a new species to fit a completely different environment on Earth – or life on another planet?

Messel Pit Fossil Site, Germany

Although not unique specifically to New Zealand, I do have fond memories of seeing a quick glimpse of the Messel Pit Fossil Site, located not far from Frankfurt in Germany. A UNESCO world heritage site since 1995, I was keen to have a look. Unfortunately I didn’t have the time to see the fossil site in the caldera of once a volcanic lake. I was still lucky to see the museum at least, which displayed fossils from the Eocene era, 47-50 million years old that had been preserved in an anaerobic environment. Shale and resin remains are rich and the Messel Fossil site is claimed to be one of the most diverse fossil sites in the world.

So what was life like around 47 million years ago? Floral diversity was rich. Green and golden algae were abundant along with diatoms and dinoflagellates. Coniferous and fern remains are rare but what is a treasure trove is the large numbers of flowering plant remains, with leaves, seeds, fruits and flowers clearly seen. So far, 96 families of angiosperms have been identified, of which 15 are monocotyledons and 81 dicotyledons. The vegetation was indicative of a lush tropical region, continental plate movement has steered this region further from the equator since.

Insects have also been recorded and fossiled with accuracy – so detailed and artistic. Most of the insects identified were land dwellers, of which 60% were beetles. Bees, wasps and ants were also abundant but their fossils more rare. Cicadas are quite diverse with relatively large wingspans. A number of fish species have been discovered and are sometimes referred to as ‘living fossils’, with enamel-covered scales and a snout similar to a crocodile. Amphibians were fascinating, with a number of frogs, snakes, lizards, turtles and crocodiles preserved beautifully. These species were at their peak of their diversity 250 – 65 million years ago. Snakes make up the majority of the reptile finds, although fossils of venomous snakes have not been found to date. Birds are the most common land vertebrates at Messel Pit; over 50 bird species have been identified and generally thought to be tree dwelling. Most of the bird fossils were in an excellent state of preservation with even colour patterns preserved. Birds of paradise, crows, finches, hummingbirds, flamingos and parrot ancestors have all been recorded.

Without a doubt, it is the mammals that have stolen the stage at Messel Pit. This was the age of the mammals, with the extinction of the dinosaurs around 65 million years ago. Skeletons, hair, wing membranes and intestinal contents have all been found. 45 species of marsupials, insectivores, bats, primates, edentates, rodents, carnivores and odd/even-toed ungulates have all been revealed. Anteaters were abundant, but it was the bats that were by far the most commonly found mammal specimens. Over 700 fossil specimens are related to seven species, with sophiscated wing structures and sensory systems. Marsupials no longer existed in Europe, yet early traces of possum like species have been discovered. Hoofed mammals were found, including the rhinoceros and tapirs, but it was the horses that maintained the most prevalent collection of fossils (at least 61 complete horse skeletons).

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Artwork by blogger

For the future …

The Earth supports an incredible amount of biodiversity of life. Acknowledging Earth’s history provides potential insight for how life will evolve next, and more importantly the implications of environmental degradation and climate change. It’s fascinating to relive history and even more intriguing to inspire the imagination of students to create their own species. The creation of fossils may just fantasise the minds of young evolutionary scientists and what may happen next.

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Artwork by blogger

Enchanted Classroom

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Auckland War Memorial Museum

The museum is such a great place to inspire learning, I think of them as ‘an enchanted classroom’. Even if the logistics of getting to a museum is difficult, there are often great resources available on their websites, catered primarily for teachers and school curriculums.

New Zealand Museums

While at teacher’s college, I naturally spent some time at Auckland’s War Memorial Museum. I have always remembered the wonderful exhibit on volcanoes on the first floor. From the scientific history of volcanoes to hearing about the human experiences, I felt the ground tremble. Fascinating and frightening, I left being reminded that volcanoes deserve respect. The Canterbury Museum offers a range of exhibits and programmes, from fossils, rocks and Antarctic exhibits being the most relevant to the Earth and Space Science curriculum. In co-ordination with Canterbury Museum there is also Quake City Exhibit located on Cashel Street in Christchurch. This museum is a unique multi media attraction aimed at engaging and educating visitors about Canterbury’s earthquakes. I’ve never been to a museum purely based on earthquake history. But this is Christchurch’s dramatic history since 2010. Well perhaps not so unique.

The entrance to the museum was greeted by Maori legends followed by the history of major earthquakes in New Zealand. From what is an earthquake and liquefaction, to the hero’s and emergency response team, the museum covered it all. The destruction and rebuilding of historic buildings was also recognised, notably Christchurch Cathedral and Cathedral of the Blessed Sacrament (Christchurch Basilica).

I was to discover that the Canterbury region had experienced a range of earthquakes in the late 1800’s. In 1888 North Canterbury experienced an earthquake of magnitude 7.3, it actually toppled 40 feet of the Cathedral spire. Outside of living memory, earthquakes are back – it’s history repeating itself.

Natural History Museums

I have been fortunate to see some wonderful natural history museums around the world. The Natural History Museum in London and the American Museum of Natural History in New York are among my favourites. The Natural History Museum is beautiful with more than 80 million specimens to adore. From animal and dinosaur skeletons, fossils, gemstones, minerals and many other historic artworks and specimens that entertain the eye and mind. For natural history lovers, at least 300 scientists are based at the museum’s Darwin Centre, where visitors can watch them work in laboratories.

My memories of Frankfurt’s Natural History Museum, Senckenberg was artistic. With 10,000 exhibits there was plenty to view, although most of the information was written in German. Fortunately, diagrams and drawings enhanced the learning experience. I also enjoyed looking at a class of students drawing dinosaurs. Although it appeared to be an art class, it reminded me of the power of visualisation. Do students draw enough during science classes? It would certainly help some.

Museum Education

The American Museum of Natural History in New York is now offering a Masters degree designed specifically for Earth Science education. The Masters of Arts in Teaching is delivered in partnership with the Richard Gilder Graduate School. Over a period of 15 months, students learn science coursework in a world class natural history museum, working alongside scientists and teachers in an urban residency program.  In response to a critical shortage of science teachers in the New York state, this partnership of education combines academic theory and learning specialising in Earth Science for grades 7 – 12. It’s incredible how education is becoming so diverse, but education needs to be marketable like any other business. This programme immensely appealed to me.

 

Beyond Planet Earth

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NASA, Kennedy Space Station, Florida

3,2,1 lift off!  A significant component of the new science curriculum engages students interests in space. I often found students fascinated by this topic – it inspires some imagination and philosophical questioning. What really is out there? Just how big is our universe?

New Zealand has a number of planetariums and tours that are run throughout the country. Recently I have visited the Otago Museum to check out the planetarium. A series of three different screenings are shown throughout the day, from observing the night’s constellations, through to the origins of the universe and Maori legends. I enjoyed them all.

What I have found of teaching interest lately is the aerospace studies subject offered in a number of secondary schools in Queensland, Australia. Aerospace studies, is catered for students who are seeking a foundation in the aviation and aerospace industry. Key topics include aeronautics and astronautics, aviation operations, safety management systems and the business of aviation and aerospace. Modules are designed to further students’ education, training and employment opportunities in this field. With my own personal interests in flying and having worked in aviation for seven years, I was particularly enthusiastic to discover this subject on offer to students.

NASA

I’ve always been fascinated to explore beyond planet earth. Perhaps, watching documentaries about astronauts sparked such an interest. A visit to NASA in Houston further fuelled that inspiration last year. Well, at the very least, I got to touch a moon rock! Visiting Johnson Space Centre at Houston was fascinating and immensely informative. Some people told me they only needed two hours to visit – I needed two days.

I have been oblivious to space travel accomplishments over the past few decades. Six space shuttles have been built and numerous missions completed, from Mars to Gemini to the Apollo Missions. There are nearly 2500 moon rocks at the Johnson Space Centre. The moon rocks are whitish-grey in colour, as they have not been exposed to the Earth’s atmosphere. The basaltic composition of the moon rocks is incredibly similar to that of Iceland and Hawaii’s lava flows. Predominant metals found on the moon were aluminium, iron, magnesium, titanium and calcium.

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NASA, Kennedy Space Center, Florida

The international space station has further paved the way for space travel and research. It orbits quickly, at 17,500 miles per hour, 250 miles above the earth’s surface. Astronauts commonly stay for six months at a time, heavily involved in their area of research. What was of interest to me was their existence in space. It’s an extreme environment to exist in, and thanks to innovative engineering and technology, it’s a dream come true for astronauts. But it is not all easy. With no air pressure, oxygen and extreme temperatures and radiation it’s not for the faint hearted. With no gravity, eyes and ears cannot decipher movement and orientation of the body, which can cause motion sickness, headaches and vomiting.

Food is a special challenge, for there are no refrigerators in space. Dry food is common along with a lot of powdered food. Another craft is responsible for the regular delivery of food and removal of wastes. Muscle weakness is common and bones become weaker. Astronauts often feel considerably weaker when arriving back to Earth. The astronauts are expected to exercise for two hours per day due to the lack of gravity. If an orbit takes 90 minutes – that is one fast bike ride around the earth. It’s an ongoing mission!

Six months at least of space travel is required to reach Mars, an ambition NASA hopes to achieve by 2030, or 2035 at the latest. Water was once thought to have been present, due to the geomorphological features present on Mar’s surface. The fascination if life has and can exist on Mars is the driving force behind NASA’s pursuit to get there. Now that is bold ambitions.

Volcanic Hot Spots

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Teide National Park, Tenerife, Canary Islands

Geological time frame is not always easy for students to conceptualise. In fact, drafting maps and diagrams is a great start, along with the use of analogies. I remember being told by my teacher, that plate tectonics move at about the speed that your fingernails grow, which is actually the plate tectonic movement in New Zealand. Of course, not correct for all plate tectonic movements, but it’s a great start to visualising the geological time scale.  This blog covers material specific to New Zealand’s teaching units of physical principles related to the Earth System and extreme Earth events in New Zealand.

New Zealand

Let’s look at New Zealand – it is quite the geological laboratory. We can thank the collision of the Australian and Pacific Plates for this. It’s an ancient story. Let’s reverse 500 million years ago, to a time when a super-continent called Gondwanaland existed. A lot has happened since then, with continents South America, Africa, Madagascar, India, Antarctica and Australia splitting apart 160 million years ago. New Zealand began its identity 85 million years ago when it separated from Australia and Antarctica. Well, that’s the geologist’s story according to plate tectonic theory.

Tectonic forces have significantly sculptured New Zealand’s landscape. It’s complex, but it is a masterpiece. The turbulent battles between the Pacific and Australian tectonic plates have created volcanoes, tsunamis and earthquakes. The two plate tectonics are seriously twisted like a corkscrew. In the North Island the Pacific plate is descending below the Australian plate, yet the reverse is happening in the South Island, with the Australian plate descending below the Pacific plate. In the centre of the South Island, the Southern Alps are being formed as both plate boundaries are colliding and sliding past each other. It’s very twisted indeed.

Volcanoes form in three ways; divergent plate boundaries spread mid-oceanic ridges apart and magma rises from the mantle; subduction plate boundaries melts solid rock aided by super heated water; and lastly a plume of magma rising to the surface through convection known as an hot spot. Intra-plate volcanoes are considered hotspots and not specifically related to plate boundaries and plate movements. As plate tectonics move across a hot spot, a chain of oceanic islands are created such as the Hawaiian and Galapagos Islands. Yellowstone’s volcanic hot spot in the United States is unique in that it has evolved on thin continental crust. New Zealand’s hot spot volcanic activity shares an equally unusual story.

So where is the hotspot volcanic activity in New Zealand? Currently, there are no active volcanoes in the South Island. However, if we rewind time, basaltic volcanic activity was alive and often produced scoria cones and lava flows. This was the case in the formation of Otago’s peninsula and Banks Peninsula approximately 10-16 million years ago. Auckland’s volcanic field is another example of an intra-plate hot spot. Each volcano will usually erupt once, with the magma finding a new way to the surface each time to create a new volcano. However, this makes volcanic predictions more difficult, a challenge considering Auckland’s volcanic field is still active.

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Otago Peninsula, New Zealand

A large majority of volcanoes in New Zealand have been formed from the subduction of one plate beneath another. It causes rock to melt in the mantle from the heated water that is pushed down, and eventually that energy is released to produce a  volcano. Both andesitic and rhyolitic volcanoes are found in the subduction zone of the North Island. White Island, Mount Ruapehu, and Mount Tongariro have been andesitic volcanic eruptions, forming steep strato-volcanoes. There has been a bit of action lately, with Ruapehu erupting about once a decade. White island is very active, erupting on a frequent basis. Rhyolitic volcanoes erupt more violently, often producing calderas such as Lake Taupo and Lake Rotorua. You would want to stand right back from such action.

Hawaii, Mauritius and Canary Islands

Warm, lush vegetative islands, with sandy beaches paints a picture of paradise. The landscape is inviting. Hawaii is a hot spot – in fact it is one of the most heavily studied hot spots in the world. Underwater volcanoes will continue to form; some will build to become islands as the Pacific plate gradually glides it way across the hot spot. Currently several volcanoes are either active or dormant and more than 100 are extinct – they continue to be eroded by ocean waves to form coral reefs and atolls. The lava is predominantly igneous basalt, indicative of oceanic hot spot activity. Jaggered hilly terrain on the islands, paint a landscape full of volcanic history.

The island of Mauritius located just 20 degrees south of the equator is also a tropical paradise. Volcanic activity from the Reunion hot spot plume has created an island comprised entirely of volcanic rocks. On first impressions, visiting Mauritius reminded of the landscape in Hawaii. The jaggered crated rims and lush vegetative crops are feed by rich volcanic soils. Although this time I was seeing plenty of sugar cane grown as opposed to pineapples. The highlight was seeing Chamarel, the seven colours of the Earth, formed by ancient lava flows. Without the sunlight, it was slightly duller, but it was still visible to see the unique colour bands running through the soils.

Tenerife is part of the Canary Islands that I visited last year in 2015. It’s a stratovolcano and it is assumed to have resulted from hot spot activity, although other theories exist. Tenerife entertains a complex history of volcanic eruptions that became more explosive as the island grew in height above the ocean floor. The last recorded eruption occurred in 1909 and is still regarded as an active volcano. It is a strange appearance, as if we had landed on Mars. But it is different, and striking for it. In fact, scientists use Teide National Park as a reference point for studies related to Mars, in particular analysing environmental and geological formations. Now wouldn’t that be an adventure – a journey to Mars. But then that is a whole new story of scientific adventure to behold.

Wetland Wonders

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Everglades National Park, Florida

I think wetlands deserve some recognition. Although a little removed from the blog’s hot spot activity on tectonic forces, it’s still connected to the process.

I have always been intrigued to see the Everglades National Park in Florida. Accredited as being the first national park for the protection of an ecological wilderness in the USA, I was keen to check it out early this year. Saving the glades has become a crucial concern as biodiversity rapidly diminishes. The ‘Rivers of Grass” are no more than 8 feet above sea level, yet urbanisation and population pressures have significantly impacted on the water level drainage and supply. On average, 800 people moved to Florida each day. I find that incredible! The Everglades Restoration plan seeks to return water to more natural patterns and distribution throughout the ecosystem. An ambitious plan for the next 30 years.

Christchurch Liquefaction

Christchurch experienced significant liquefaction after the earthquakes. It was a series issue, with silt, sand and water bubbling up in people’s backyards. It happened in the streets, and even through the floors of buildings. The damage was extensive to buildings and infrastructure, particularly in the eastern suburbs of Christchurch, where the water table is very high along with loosely packed sediments in the soil.

So what is liquefaction? During an earthquake, silt and sand grains in the soil are re-arranged as water is squeezed out. They lose their strength. The soil behaves more like a liquid than a solid, as it is forced up through cracks and crevasses. It can no longer support the weight of buildings and roads above it. In fact liquefaction often forms what is called a sand volcano. Liquefaction can cause the ground to subside and also cause lateral spreading on downward slopes. Liquefaction would make for a fun experiment – rather in the lab of course than in the real world. This would relate well for the teaching unit to carry out a practical Earth and Space Science investigation.

Soft sediments beneath Christchurch enhanced earthquake motion. It’s a dangerous recipe. As seismic wave energy passes from stiffer rock through to softer sediments, it deforms the sediments more in order to balance the energy transferred. Continual pulses of seismic energy travel further in the weaker upper layers, than the stronger layers below. As a consequence, upper layers fall under gravity only to be hit again by lower layer earth movements. This produced high impacts of energy and magnified the entire process of liquefaction, separating water and layers of sediment. In effect, the ground was shaking like leaves on a tree blowing in the wind.

Christchurch city has been built upon land that was once a wetland. Travis Wetland Nature Heritage Park is a reminder of what the natural landscape once looked like. Nature can have a powerful way of reminding us what was there before we built cities.

One particular story I have enjoyed reading about was called Rocky. With steep cliffs surrounding the Port Hills region of Christchurch, rock falls were a series threat after the earthquakes, particularly in 2011. Many homes surrounding this area had to be abandoned, as cliff faces collapsed. Rocks came tumbling down, causing significant damage in some instances. One boulder crashed through a roof of a garage in Morgan Valleys Road. With its momentum it continued to roll through a wall and into the entrance hallway of the house. Ironically, the owner put the boulder up for sale in Trade Me’s auction website and called him ‘Rocky’. Thousands of hits turned Rocky into one of the most popular rocks in New Zealand. Amazingly, the auction raised $60,000 for charity. Having been won by NZ Ski, Rocky’s new home will be in Mt Hutt ski field in Methven. Now that is one remarkable rocky story.