Descoberto fragmento de zircão com 4,4 mil milhões de anos

    Uma equipa de cientistas datou de pequeno fragmento de zircão com 4,4 mil milhões de anos de idade, segundo um artigo publicado este domingo na revista Nature Geoscience. O pedaço mais antigo de crosta do planeta Terra foi encontrado num terreno de ovelhas, na Região Oeste da Austrália.   

Mineral de zircão. (Fonte: Público)

   Segundo a equipa, a descoberta indica que a Terra formou a crosta terrestre pouco tempo depois da sua origem, há 4,54 mil milhões de anos, sendo este mineral o vestígio dessa crosta primordial.

Rio Tinto e a automatização do transporte de minério

Rio Tinto lança um ambicioso programa de automatização do transporte de minério. (fonte)

A internacional mineira, Rio Tinto, anunciou que irá automatizar o transporte de minério a longas distâncias na mina de Pilbara, Austrália. O novo sistema AutoHaul, que deverá estar completamente operacional a partir de 2015, irá incluir a automatização dos sistemas de transporte ferroviário, sendo que a Rio Tinto pretende também automatizar parte do seu transporte rodoviário (camiões).

Marcas Eternas: "Cratera Wolfe Creek , Austrália Ocidental"

   A Cratera de Wolfe é uma cratera provocada pelo impacto de um meteorito localizada na região oeste da Austrália, no Parque Nacional de Wolfe Creek a 105 km na direcção sul de Halls Creek.

   Com cerca de 875 metros de diâmetro e 60 metros de profundidade, estima-se que a sua idade é de pouco menos de 300 mil anos e que o meteorito que a causou tivesse 50.000 toneladas.

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Adaptado de:

-http://hypescience.com/marcas-eternas-16-minas-e-crateras-do-mundo-todo/

-http://pt.wikipedia.org/wiki/Grande_Deserto_Arenoso

-http://pt.wikipedia.org/wiki/Cratera_de_Wolf_Creek

Australia's largest rough pink diamond unearthed

An Australian mining company says it has found a 12.76-carat pink diamond, the largest rough pink diamond found in the country.
Image: Rio Tinto

The rare diamond was found at Rio Tinto's Argyle diamond mine in Western Australia's East Kimberly region.

Estimated to be worth millions, it has been named the Argyle Pink Jubilee, and is being cut and polished in Perth.

It will be sold later this year after being shown around the world, including in New York and Hong Kong.

The process of polishing and cutting, which began in Perth on Tuesday, is expected to take about 10 days. The diamond will then be graded by a team of international experts.

More than 90% of the pink diamonds in the world come from the Argyle mine, a Rio Tinto statement said.

The Argyle Pink Jubilee is a light pink diamond, the company said. It is similar in colour to The Williamson Pink - the diamond found in Tanzania that Queen Elizabeth II received as a wedding gift and which was subsequently set into a brooch for her coronation.

A Rio Tinto spokesperson said that a diamond of this calibre was ''unprecedented''.

''It has taken 26 years of Argyle production to unearth this stone and we may never see one like this again,'' said Argyle Pink Diamonds Manager Josephine Johnson.

In 2010, a rare 24.78-carat "fancy intense pink" diamond was sold for a record-breaking $46 million (£29m), the highest price ever paid for a jewel, to a well-known British dealer at an auction in Geneva.

That diamond had been in a private collection for 60 years.

Fonte: http://www.bbc.co.uk

The Ediacaran Period

The Ediacaran Period was a time when bizarre-shaped soft-bodied creatures dwelt on the sea floor, just prior to the explosion of skeletal life forms in the Cambrian Period. The Ediacaran is the last period of the Proterozoic Eon, dating from 650 Ma to 542 Ma, is named after the type-fossil locality at the Ediacara Hills in South Australia. 

Wilpena Pound (above) is a massive curved natural syncline in southern Australia.  

This period represents the ending of a global galciation, one that held almost entirely the Earth's surface (an effect known as the Snowball Earth), and marks the first worldwide appearence of somewhat complicated trace fossils.

 

At that time, all the continents were together in the supercontinent Pannotia. Before Pannotia, the former global supercontinent was Rodinia, broken about 800 Ma. Rodinia displacement led to the birth of the Ocean Pantalassa (or Paleo-Pacific) and eight continents who met again after to form the supercontinent Pannotia. 540 Ma ago, only after 60 Ma of its formation, Pannotia fragmented, originating the supercontinent Gondwana and three small continents, Laurentia, Siberia and Baltica. At the end of the Paleozoic the continents will met again one more time to form Pangea, the last supercontinent.

The supercontinent Pannotia (above), 550Ma ago.

The study of Ediacaran Period life records is relevant to the search for extraterrestrial life because conditions similar to Snowball Earth might exist elsewhere in the solar system. Beneath the icy crust of Jupiter´s moon Europa, an ocean has been suggested, perhaps making complex life feasible there.

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Adpated from:

Geologica (Amazon.com link) 

Wikipedia (Ediacaran, Snowball Earth, Período Ediacário)