New View of Tectonic Plates Through Computer Modeling of Earth’s Mantle Flow, Plate Motions, and Fault Zones

Plate boundaries, which can be seen as narrow red lines are resolved using an adaptively refined mesh with 1km local resolution. Shown are the Pacific and the Australian tectonic plates and the New Hebrides and Tonga microplates. (Credit: Georg Stadler, Institute for Computational Engineering & Sciences, UT Austin)

Computational scientists and geophysicists at the University of Texas at Austin and the California Institute of Technology (Caltech) have developed new computer algorithms that for the first time allow for the simultaneous modeling of Earth’s mantle flow, large-scale tectonic plate motions, and the behavior of individual fault zones, to produce an unprecedented view of plate tectonics and the forces that drive it.

A paper describing the whole-earth model and its underlying algorithms will be published in the August 27 issue of the journal Science and also featured on the cover.The work “illustrates the interplay between making important advances in science and pushing the envelope of computational science.

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Sinabung erupts in Sumatra

Mount Sinabung volcano on Sumatra erupted shortly after midnight local time on 29 August 2010, producing lava and throwing ash 1500 metres above the summit. Local inhabitants fleeing their homes have spoken of ’thick black smoke, small stones and sulphur’ being produced by the volcano, according to AFP: one local man reportedly died as a result of breathing difficulties suffered during the eruption.

Mount Sinabung is a 2460-metre stratovolcano in northern Sumatra, about 60 km SW of the city of Medan. An uncertain eruption is given by the Global Volcanism Program for 1881 and sulphurous gas emissions were apparently reported from the summit in 1912, but there are no historical records of confirmed eruptive activity.

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Gems and The Moh’s Scale

In the old days, people believed gems held magical powers. Gems are very valuable.

Diamond is the hardest naturally occurring substance with a hardness of 10. Its crystal system is cubic because it has 4 equidistant neighboring crystals. Its specific gravity is 3.5. The word diamond means adamas in Greek, meaning “unconquerable”. That’s why Napoleon wanted the Regent, or Pitt diamond set into the hilt of his sword.

Topaz-the name for this substance is a misnomer. The word topaz actually means Zabargad in Greek, which is an island in the Red Sea, a source of peridot. Topaz’s crystal structure is orthorhombic. The hardness of topaz is 8, though it can be broken easily due to its 1 perfect direction of cleavage. The specific gravity is 3.52-3.56, which is very close to diamond’s.

Tourmaline is a very interesting gem. It has a trigonal crystal system and a hardness of 7-7.5. Its specific gravity is 3-3.25. What is really interesting is that if this gem was heated, one side would be positively charged, the other negatively. That’s why there is a watermelon tourmaline. Since it can produce electricity, it has a tendency to attract dust.

Quartz is really just silicon dioxide. Quartz is an igneous rock and its hardness is 7. Its crystal system is trigonal and its specific gravity is 2.65. Quartz is hard to break and has no cleavage. Quartz is the main percentage of dust. Therefore, dust can damage gems with a hardness of 6.99 and lower. Quartz is only pure when it is colorless. Rose quartz has iron and titanium too. Smoky quartz has aluminum.

The Moh’s Scale

The Moh’s Scale is the scale that organizes the rocks in order of hardness with 10 being the hardest and 1 the softest. In other words, diamond is the hardest and talc is the softest. This is an easy way to see which rocks are harder than others.

The Moh’s Scale is not to scale though. Diamond is a lot harder than corundum but corundum isn’t much harder than quartz.

1. Talc

2. Gypsum

3. Calcite

4. Flourite

5. Apatite

6. Orthoclase

7. Topaz

8. Quartz

9. Corundum

10. Diamond

Links

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10 Types of Shelters for Natural Disasters

Guest Post by Brenda Chapman

When a natural disaster strikes, there’s nothing people want more than the bare necessities and a roof over their heads. Disaster relief groups go to great lengths to ensure that victims have shelter from the storm and a place to dwell during the aftermath, but when facilities become full the help has to get creative. Thankfully, there are hundreds of affordable shelters on the market and self-build homes that provide shelter and hope in these trying times. Here are 10 types of shelters for natural disasters:

Shipping Container Houses

In recent years, recycled shipping containers have been used as emergency housing for natural disaster victims. Shipping containers have a sturdy structure and impenetrable exterior that makes them an ideal shelter for earthquakes, hurricanes and other natural disasters. Not only are they structurally-sound and plentiful, but shipping containers make beautiful, modular homes.

Relief Tents

Disaster relief tents are convenient, portable and easy-to-install structures that use strong frames and high-quality fabrics that are flame retardant, water resistant and give victims privacy. Tents can typically house an entire family or a group of individuals with enough space to create separate rooms. Depending on the construction and materials used, some disaster tents are capable of withstanding severe weather and certain natural disasters.

Shelter Canopies

Shelter canopies aren’t just four poles with an overhead roof, they can also come with windows, doors and protective lining that shields victims from water, bugs and other outside elements. Canopies are extremely portable and rapidly deployed in times of need. Although canopies are mostly temporary houses, they can be customized with generators, lights, beds, tables and other amenities to make it feel like home.

Foldable Shelters

Like the bellows of an accordion, foldable shelters expand into homes of various shapes and sizes and easily fold back into place to be transported or stowed away. Foldable shelters are typically made out of polypropylene, provide relief for four or more people and are relatively inexpensive to buy. The unique folding design of this shelter makes it one of the most portable and immediate shelters for natural disaster victims today.

Plastic Sheeting Homes

Many temporary houses for natural disaster victims are made from high-quality plastic sheeting, which is portable, long-lasting, and shields against weather and other elements. Plastic sheeting can be used alone to create single-family homes, community shelters, latrines or to reinforce current housing.

Sandbag Shelters

Sandbag shelters are both sturdy and artistic structures that can resist hurricanes, earthquakes and floods. Sandbag shelters are extremely versatile in their shape, construction and amenities. Mirroring the adobe-style homes, sandbag shelters can be used as temporary shelters or transformed into self-sustaining houses.

Hexayurt Shelters

For less than $100 dollars to build, hexayurt homes provide an inexpensive, eco-friendly and sustainable form of shelter for natural disaster victims. This geometric shaped shelter can be made with sheets of plywood, OSB, coroplast, hexacomb cardboard and other construction materials that are screwed together, painted and customized to your liking. They are roomy enough for windows, doors, stove fittings and room partitions and have the ability to withstand various climates and weather conditions for years.

Bamboo Houses

Bamboo houses have become a widely-recognized form of shelter for natural disaster victims and those who are prone to such catastrophes. Bamboo is incredibly flexible and strong, with twice the compression strength of concrete and half the tensile strength of steel. If properly constructed and treated, bamboo houses have the power to withstand deadly earthquakes, typhoons and other natural disasters.

InterShelter

InterShelters are dome-shaped homes, made out of a fiberglass-composite mixture and a fireproof structure. They can house an entire family and are easily broken down, rebuilt and relocated for various shelter needs. Each dome-home weighs 70 pounds, but they can withstand a Category 4 hurricane, an 8.5-magnitude earthquake and other extreme weather or natural disasters.

Concrete Shelters

In an effort to create permanent housing during natural disaster crises, the Concrete Canvas created a building-in-a-bag that only needs water and air to inflate. This portable shelter is made of cement-impregnated cloth expands and hardens in one day and is completely waterproof, fireproof and chemically resistant. Doors and windows can be cut for ventilation, and any unset cloth can be tailored to meet the occupants’ needs.

first published here

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