Earth & Environmental Sciences Blogs

The Rio Tinto (red river) is a river in southwestern Spain that begins in Andalusia's Sierra Morena Mountains. It flows south-southwest until it reaches the Gulf of Cadiz in Huelva. Copper, silver, gold, and other minerals have been mined along the riverbank since ancient times. Iberians and Tartessians began mining the site around 3,000 BCE, followed by the Phoenicians, Greeks, Romans, Visigoths, and Moors. The mines were rediscovered in 1556 after a period of abandonment, and the Spanish government resumed operations in 1724. Figure 1 Flowing channel of Rio Tinto in Spain. Ro Tinto is known for being very acidic (pH 2) as a result of the mining and its deep reddish tint is owing to iron dissolved in the water. Because of the high quantities of heavy metals in the river, acid mine drainage from the mines causes serious environmental problems. The Rio Tinto Company was founded in 1873 to operate the mines, and by the end of the twentieth century, it had grown to become one of the

 Introduction Alba Mons (also known as the Arcadia ring; formerly and still occasionally known as Alba Patera, a word that has since been restricted to the volcano's top caldera) is a volcano in Mars' northern Tharsis region. In terms of area, it is the largest volcano on Mars, with volcanic flow fields extending for at least a kilometer from its summit. Despite having a span equivalent to that of the United States, the volcano barely reaches an elevation of at its greatest point. This is roughly one-third the height of Olympus Mons, the world's tallest volcano. Alba Mons' flanks have extremely gentle slopes. The average slope along the volcano's northern (and steepest) face is 0.5 degrees, which is more than five times lower than the slopes on the other great Tharsis volcanoes. Alba Mons appears in wide profile to be a massive but scarcely elevated welt on the planet's surface. It's a one-of-a-kind volcanic edifice that doesn't exist either on Earth or

Introduction A marine invertebrate belonging to the Crinoidea class (phylum Echinodermata) with a cup-shaped body and five or more flexible and active arms. The reproductive organs are housed in the arms, which are bordered with feathery projections (pinnules) and hold many tube feet with sensory functions. Cilia (minor, hair-like projections) whisk food particles toward the mouth through open grooves in the tentacles. Figure 1  Periechocrinus, a Silurian crinoid. BGS © UKRI. They are an early fossil group that originally arose 300 million years before dinosaurs in the mid-Cambrian oceans. They thrived during the Paleozoic and Mesozoic periods, and some still exist now. Living forms provide insights regarding how prehistoric crinoids must have lived, even if they differ in appearance from their fossil predecessors. Anatomy A ring of branching arms (brachia) wraps around the top of a globe-shaped, cup-like structure (calyx), which houses the animal's primary body. The calyx