What are stratovolcanoes?
By: Jose Juan Gutierrez
Stratovolcanoes (composite volcanoes) are steep-sided, conical volcanoes. They are formed by many layers of hardened lava flows, pyroclastic flows and lahar flows. Stratovocanoes are most often formed on continental land, and have gentle slopes at the base that gradually rise until they reach their steepest...
By: J. Lang Wood
The Ordovician period is a part of the Paleozoic era. It occurred between the Cambrian and Silurian Eras millions of years ago. The Ordovician was at first thought to be part of the previous periods, but in 1879, Sir Charles Lapworth pointed out the differences...
By: Dr. Bryan Katz
For the purposes of this article, it is useful to divide the last millennium into three eras: the Medieval Warm Period, the Little Ice Age, and the Fossil Fuel era, marked by the Industrial Revolution and global warming. The Medieval Warm Period: 800 – 1300...
Igneous rocks: Rhyolite
By: Jose Juan Gutierrez
Rhyolite is a fine-grained igneous extrusive rock of high silica content or felsic rock. Rhyolite is composed principally of quartz and feldspar minerals, and traces of biotite, plagioclase, mica, amphibiotes, and pyroxenes. It resembles granite in mineral composition, although granite is an intrusive igneous rock...
By: David Jefferson
Creating a record of climate change for the last 1000 years is important to put more recent measurements and predictions of future climate change into perspective and to answer the questions of anthropomorphic or man made climate change. People can and do affect the weather...
The ecological importance of mountains
By: Christyl Rivers
Mountains are essential for life on earth as it is known. Their greatest contribution is the moisture they trap, through weather and snow fall. The amount of snow held on slopes and glaciers determines how much water or drought a region far below, even thousands...
By: David Jefferson
People have been extracting resources from the earth forever. From the first human that built a fire or killed an animal to modern extraction of hydrogen for rocket fuel. It's what people do. Some of these activities have minimal impact or might be considered natural...
By: Cameron Scott
It's never fun when lightning strikes your car. Paint peels. All your electronics could be fried. Your tires could blow. And just to add insult to injury, the thunder's going be a crash like you've never heard before. But as long as you're not in...
By: B. J. Deming
The Atlantic Ocean and its marginal seas cover approximately 20% of Earth’s surface, extending from the eastern shores of North and South America to the western coasts of Europe, the Strait of Gibraltar and Africa. To the north is the Arctic Ocean and, some...
Effects of environmental stress
By: Christyl Rivers
Warmer temperatures world-wide and degraded environment are affecting earth in myriad ways. Among these are melting polar ice, rising sea levels, acidification of oceans, increased amounts of heat with diminished ozone layer protection, increased wild fires, storms, vanishing species, and species migration, less arable crop...

 

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