Possible parent rocks of gneiss are granite, shale, gabbro or diorite. Some rocks metamorphose, or change, from one particular kind of rock, but gneiss forms from one of several types. Another name for the parent rock is the protolith.
A:The specific type of rock that forms when magma cools at the Earth's surface is extrusive igneous rock. Igneous rock forms when magma cools, but where the magma cools determines the type of igneous rock that forms. Igneous rock gets its name from the Greek word for fire and is so called due to the extremely hot liquid from which the rocks originate.
A:Rocks come from magma, which is the molten material found within the earth. When magma cools, either above or below the earth's surface, it crystallizes and forms the igneous rocks that can later be changed into metamorphic or sedimentary rocks. Magma, which can be considered molten rock, is referred to as lava when it reaches the earth's surface.
A:Geology is the study of earth, the materials of which it is made, the structure of those materials and the effects of the natural forces acting upon them and is important to civil engineering because all work performed by civil engineers involves earth and its features. Fundamental understanding of geology is so important that it is a requirement in university-level civil engineering programs.
A:Real silver is identified by its sound, its lack of magnetic qualities and by its ability to conduct heat. For instance, when tapped together, two silver coins emit a high, clear tone. The bell-like ring continues for a second or two.
A:Geodes are mostly found in deserts, volcanic ash beds and areas with limestone throughout the world. In the United States, common geode sites include Arizona, California, Iowa, Nevada and Utah. The most abundant geode sites in California are Riverside and Imperial counties.
A:Igneous rocks are often used for construction because of their durability. Igneous rocks can also be separated to access the various valuable metals and minerals inside them. Igneous rocks form as magma comes to or near the surface of the Earth; cooling and hardening because of its distance from the inner parts of the Earth where magma forms.
A:Fossil fuels are formed the gradual accumulation of organic remains on the sea floor. As the accumulation rate increases, the organic remains are subjected to heat and pressure, which leads to fossil-fuel formation.
A:According to the U.S. General Services Administration, limestone is important because it is widely used in architectural applications for walls, decorative trim and veneer. It is less commonly used in making sculptures because of its porosity and softness.
A:Sedimentary rocks are formed by the deposition of mud, clay, sand and other small particles on the surface of the Earth. Sedimentation can occur in many different environments, including lakes, rivers, deserts and oceans. The sediment is deposited in layers that are compressed over time and turned into solid rock.
A:Salt, or sodium chloride, is a non-renewable resource. A resource is defined as renewable only if it is self-replenishing. While new salt is being formed by natural processes in the earth, the timescale for that formation is too vast for salt to be considered self-replenishing in terms of human use.
A:A plateau is formed by a process of geological uplift, either due to the collision of continental plates, pressure from magma below or the burial of land by volcanic lava and ash flows, resulting in a high, flat surface. These are very similar to processes that give rise to mountains and mountain ranges. The only major difference is that a plateau is flat while mountains are peaked.
A:Minerals are solid, naturally occurring, inorganic compounds that possess an orderly internal structure and a regular chemical composition. A mineral species has to possess these five characteristics to be regarded as scientifically valid.
A:According to the Oxford University Museum of Natural History, petrified fossils form when mineral deposits replace the bones of dead creatures inside hardened sediment. Over time, these deposits completely replace the remains, forming an image of the bones out of solid rock.
A:The outer core is part of the core, which is one of the three major layers of the Earth. The core is the deepest and hottest layer and is mostly composed of metals, and it is beneath the Earth's mantle. The outer core is the first layer of the core, and it extends to a depth of approximately 2,890 kilometers below the Earth's crust and measures 2,300 kilometers thick.
A:The Encyclopedia of Arkansas explains that commercial mining of quartz is rare and occasionally consists of the use of explosives to first expose the quartz, followed by the operation of small hand tools such as chisels and rock picks to extract portions of the mineral from a quarry. Quartz is quite sensitive to temperature changes, so miners prefer not to use explosives unless absolutely necessary.
A:A mineral resource is the concentration of materials that are of economic interest in or on the crust of the Earth. Almost all minerals found on Earth are used in one way or another for economic benefit. Examples of minerals include gold, gravel, sand, aluminum, copper, limestone, clay and diamond.
A:Rock composed of layered bands of sediment is called sedimentary rock. Erosion creates sand, clay, silt and other sediment. Sediment builds up, and with the passage of time, the layers are compacted and cemented together to form sedimentary rock.
A:Absolute dating is a method of determining the specific date of a paleontological or archaeological artifact or location based on a specific time scale or calendar. Scientists base absolute dating on measurable physical or chemical changes or on written records of events.
A:The fossil record refers to the collection of physical and research evidence that paleontologists and geologists have used to prove the veracity of evolutionary theory. The physical evidence in the fossil record comes from fossilized remains of prehistoric animals.