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Flow (geomorphology)
Mass wasting, also known as mass movement, is a general term for the movement of rock or soil down slopes under the force of gravity. It differs from other processes of erosion in that the debris transported by mass wasting is not entrained in a moving medium, such as water, wind, or ice. Types of mass wasting include creep, solifluction, rockfalls, debris flows, and landslides, each with its own characteristic features, and taking place over timescales from seconds to hundreds of years. Mass wasting occurs on both terrestrial and submarine slopes, and has been observed on Earth, Mars, Venus, Jupiter's moons Io, and on many other bodies in the Solar System. Subsidence is sometimes regarded as a form of mass wasting. A distinction is then made between mass wasting by subsidence, which involves little horizontal movement, and mass wasting by slope movement. Rapid mass wasting events, such as landslides, can be deadly and destructive. More gradual mass wasting, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar System" and "solar system" structures in theinaming guidelines document. The name is commonly rendered in lower case ('solar system'), as, for example, in the ''Oxford English Dictionary'' an''Merriam-Webster's 11th Collegiate Dictionary''. is the gravity, gravitationally bound system of the Sun and the objects that orbit it. It Formation and evolution of the Solar System, formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The solar mass, vast majority (99.86%) of the system's mass is in the Sun, with most of the Jupiter mass, remaining mass contained in the planet Jupiter. The four inner Solar System, inner system planets—Mercury (planet), Mercury, Venus, Earth and Mars—are terrest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thistle 2010 From US6 Rest Area
Thistle is the common name of a group of flowering plants characterised by leaves with sharp prickles on the margins, mostly in the family Asteraceae. Prickles can also occur all over the planton the stem and on the flat parts of the leaves. These prickles are an adaptation that protects the plant from being eaten by herbivores. Typically, an involucre with a clasping shape similar to a cup or urn subtends each of a thistle's flower heads. The comparative amount of spininess varies dramatically by species. For example, ''Cirsium heterophyllum'' has minimal spininess while ''Cirsium spinosissimum'' is the opposite. Typically, species adapted to dry environments have greater spininess. The term thistle is sometimes taken to mean precisely those plants in the tribe Cardueae (synonym: Cynareae), especially the genera ''Carduus'', ''Cirsium'', and ''Onopordum''. However, plants outside this tribe are sometimes called thistles. Biennial thistles are particularly noteworthy for t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stone Rivers
A stone run (called also ''stone river'', ''stone stream'' or ''stone sea''Vitosha Nature Park: Basic Information. Landscape. Vitosha Nature Park website.) is a rock landform resulting from the of particular rock varieties caused by freezing-thawing cycles in conditions during the last Ice Age. The actual formation of stone runs involved five processes: |
Weathering
Weathering is the deterioration of rocks, soils and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs ''in situ'' (on site, with little or no movement), and so is distinct from erosion, which involves the transport of rocks and minerals by agents such as water, ice, snow, wind, waves and gravity. Weathering processes are divided into ''physical'' and ''chemical weathering''. Physical weathering involves the breakdown of rocks and soils through the mechanical effects of heat, water, ice, or other agents. Chemical weathering involves the chemical reaction of water, atmospheric gases, and biologically produced chemicals with rocks and soils. Water is the principal agent behind both physical and chemical weathering, though atmospheric oxygen and carbon dioxide and the activities of biological organisms are also important. Chemical weathering by biological action is also known as biological wea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permafrost
Permafrost is ground that continuously remains below 0 °C (32 °F) for two or more years, located on land or under the ocean. Most common in the Northern Hemisphere, around 15% of the Northern Hemisphere or 11% of the global surface is underlain by permafrost, with the total area of around 18 million km2. This includes substantial areas of Alaska, Greenland, Canada and Siberia. It can also be located on mountaintops in the Southern Hemisphere and beneath ice-free areas in the Antarctic. Permafrost does not have to be the first layer that is on the ground. It can be from an inch to several miles deep under the Earth's surface. It frequently occurs in ground ice, but it can also be present in non-porous bedrock. Permafrost is formed from ice holding various types of soil, sand, and rock in combination. Permafrost contains large amounts of biomass and decomposed biomass that has been stored as methane and carbon dioxide, making tundra soil a carbon sink. As global war ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sloughing (soil) Soil sloughing is mass wasting, soil falling off bank (geography), banks and slopes due to a loss in cohesion. Soil sloughs off for Landslide#Causes, the same reasons as landslides in general, with water content, very wet soil being among the leading factors. Sloughing is a relatively shallow phenomenon involving the upperm |
