Small salt ponds numbering in the thousands are arranged on steep mountain slopes near the city of Cusco, former capital of the Inca Empire, high in the Andes Mountains of Peru. Known as Maras, and originating from a saline spring, these salt ponds have been tended carefully since Inca times 500 years ago, and possibly for hundreds (or thousands?) of years before the Incas.
Evidence indicating where ancient people collected the valuable pigment red ochre thousands of years ago may seem like an unlikely combination with underwater archaeology – but that isn’t the case. Sea levels have been substantially lower than at present for most of human existence, so we know that many traces of our history are hidden beneath water.
A birds-eye view of view the landscape as it unfolds is unique. For this reason, many travelers, and especially geologists, try to sit in window seats on airline flights. Unfortunately, many of us are not planning to travel on airplanes anytime soon...but we can admire photos!
Among the high peaks of the Andes Mountains, gold-bearing quartz veins in the granitic bedrock have been exposed by erosion from ice, wind and water. Numerous ancient small gold mines are found at altitudes that cluster around an impressively high elevation of 16,000 feet.
Rich deposits of metals, created by the dynamic geologic environment that built the rugged Andes Mountains, became intertwined with Andean cultures in the New World. The Incas and their ancestors created metal products primarily for aesthetic uses and for religious goods. This contrasts with Old World cultures, where the emphasis was on the mechanical properties of metals -- strength, hardness and sharpness—for tools and weapons.
There is a lot of misinformation floating about right now, with rumors and distortions promoted on social media and even at the top levels of governments. Unfortunately, this also extends to the realm of geologic hazards, which particularly catches my attention (and great annoyance).
Geologic time scales, which show a chronological sequence of events that have occurred during Earth’s history, become more or less embedded in the brains of geologists. As for other people – probably not so much. Having a rough idea of this history and familiarity with a few names, however, will be helpful if you like to think about natural history, and especially geology topics...
Grand Canyon, Zion, Arches, Canyonlands, and other national parks on the Colorado Plateau encompass some of the most spectacular scenery on Earth. Extending across the Four Corners region where the borders of Utah, Colorado, New Mexico, and Arizona meet...the landscape is sculpted into dramatic cliffs and arches, domes and towers, fins and hoodoos, mesas and buttes, slot canyons, and deeply carved canyons.
Jutting up from the middle of the Pacific Ocean, the Hawaiian Islands are located more than 1,800 miles from the nearest continent. They are also in the center of the Pacific tectonic plate, so the volcanoes that formed these islands have a completely different geologic history from other volcanoes around the Pacific Rim.
Machu Picchu, the mountain citadel high in the Andes Mountains of Peru, is a familiar icon of the Inca Empire. Perched high on a steep and narrow ridge between two mountain peaks, the site is ringed on three sides by the Urubamba River, a dizzying 1,600 feet below.