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Armor (hydrology)
In hydrology and geography, armor is the association of surface pebbles, rocks or boulders with stream beds or beaches. Most commonly hydrological armor occurs naturally; however, a man-made form is usually called riprap, when shorelines or stream banks are fortified for erosion protection with large boulders or sizable manufactured concrete objects. When armor is associated with beaches in the form of pebbles to medium-sized stones grading from two to 200 millimeters across, the resulting landform is often termed a ''shingle beach''. Hydrological modeling indicates that stream armor typically persists in a flood stage environment. Hjulstroms Diagram Bed armor is most often transported through entrainment, and more specifically suspension and saltation. Both of these processes involve moving the sediment both near and around the bed of a river. When a sediment is entrained it is being moved downstream through the forces between the layers of water around it, and once it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt Used In Wave Braker Beach The Hague
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
