More than 300 million years ago, during the Carboniferous Period, much of northern Illinois outside Chicago—including what is now the Mazon Creekfossil site—was alive with ancient creatures ...

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High-Grade Underground samples at Anvil: An outcrop sample returned 3.1% copper (Cu) over 0.3 metres. Anvil Prospect Potential: Recent underground samples at Anvil indicate multiple copper fissure ...

As the sun grew hotter, so did Mars, prompting much of its atmospheric carbon dioxide to rain out and ultimately get locked up in rocks.

Hydrothermal alteration, notably pervasive siderite zoning and bleaching, is a defining characteristic of the mineralized zones, with disseminated siderite sometimes extending hundreds of meters ...

Pyrite is widely distributed in lacustrine shales and has become a research focus in unconventional oil and gas exploration. Pyrite morphology is useful for identifying different types of organic ...