How long does lava take to break down?
GeologyLava flows which form on the rainy parts of Hawaii will break down to produce soil within a couple of years, whereas lava flows which form on dry parts of Hawaii can take hundreds of years to break down and produce soil. Soil is not just made from rock though, it also contains organic matter
What are joints and bedding planes?
GeologyJoints are usually vertical. Joints are considered to be lines of weakness at right angle to the bedding planes. If you take a look at picture 1, you can see a number of joints. 2. Bedding planes are the horizontal junction between the layers of rocks. What is a bedding plane? Definition of bedding plane
What are the four categories of magma?
GeologyBecause many of the properties of a magma (such as its viscosity and temperature) are observed to correlate with silica content, silicate magmas are divided into four chemical types based on silica content: felsic, intermediate, mafic, and ultramafic. What are 3 types of magma and what is their viscosity? Three general types are recognized: Basaltic
How do minerals form from hydrothermal solutions?
GeologyHydrothermal mineral deposits are accumulations of valuable minerals which formed from hot waters circulating in Earth’s crust through fractures. They eventually create metallic-rich fluids concentrated in a selected volume of rock, which become supersaturated and then precipitate ore minerals. How can hydrothermal solutions form new minerals? hydrothermal mineral deposit, any concentration of metallic minerals formed
Are all mountains fold mountains?
GeologyFold mountains are the most common type of mountain. The world’s largest mountain ranges are fold mountains. These ranges were formed over millions of years. Fold mountains are formed when two plates collide head on, and their edges crumbled, much the same way as a piece of paper folds when pushed together. Which mountains are
How did the Archean period end?
GeologyWhat happened at the end of the Archean eon? In the Archean Eon, oxygen-filled in the atmosphere, and most of the world’s iron ore was deposited. Because the Earth’s conditions stabilized, eukaryotic and multicellular life could finally emerge in the Proterozoic Eon. When did the Archean era began and end? Etymology and changes in classification
What are flute marks?
GeologyWhat is the flute mark? Typically, flute marks are bilaterally symmetrical heel-shaped hollows eroded into mud beds by debris-laden currents, acting either on prior defects on or within the bed, or on self-created defects, if the mud is insufficiently strong. Mud ripples closely resemble two-dimensional forms of current ripple. How do Flute marks form? Flute
What type of lava does Yellowstone have?
GeologyThe most likely type of volcanic eruption at Yellowstone would produce lava flows of either rhyolite or basalt. Does Yellowstone have basaltic lava? Basalt lava flows, though in lesser volume than rhyolites, have erupted throughout the 2.3 million-year volcanic history of the Yellowstone area. The magma feeding these eruptions originated in the upper part of
What are the factors that influence the formation of minerals?
GeologyPhysical and chemical conditions include factors such as temperature, pressure, presence of water, pH, and amount of oxygen available. Time is one of the most important factors because it takes time for atoms to become ordered. If time is limited, the mineral grains will remain very small. What are 3 ways minerals are formed? Minerals
What causes a rockslide?
GeologyA rockslide is a type of landslide caused by rock failure in which part of the bedding plane of failure passes through compacted rock and material collapses en masse and not in individual blocks. Note that a rockslide is similar to an avalanche because they are both slides of debris that can bury a piece