Meteorites. Geology. Physical geography. Physiography redirects here.
It is also an obsolete term for "geomorphology" Chronology of Geography, Meteorology, Paleontology, Science Philosophy, and Science Publishing. Soil science. A sylviculturist, at work Soil science is the study of soil as a natural resource on the surface of the Earth including soil formation, classification and mapping; physical, chemical, biological, and fertility properties of soils; and these properties in relation to the use and management of soils. Soil scientists have raised concerns about how to preserve soil and arable land in a world with a growing population, possible future water crisis, increasing per capita food consumption, and land degradation. Fields of study Research Dependence on and curiosity about soil, exploring the diversity and dynamics of this resource continues to yield fresh discoveries and insights.
Mapping Most empirical knowledge of soil in nature comes from soil survey efforts. Classification The Interior of the Earth. The Crust Because the crust is accessible to us, its geology has been extensively studied, and therefore much more information is known about its structure and composition than about the structure and composition of the mantle and core.
Within the crust, intricate patterns are created when rocks are redistributed and deposited in layers through the geologic processes of eruption and intrusion of lava, erosion, and consolidation of rock particles, and solidification and recrystallization of porous rock. By the large-scale process of plate tectonics, about twelve plates, which contain combinations of continents and ocean basins, have moved around on the Earth's surface through much of geologic time. The edges of the plates are marked by concentrations of earthquakes and volcanoes. Collisions of plates can produce mountains like the Himalayas, the tallest range in the world. Glaciology. Lateral moraine on a glacier joining the Gorner Glacier, Zermatt, Swiss Alps.
The moraine is the high bank of debris in the top left hand quarter of the picture. For more explanation, click on the picture. Glaciology (from the Franco-Provençal language: glace, "ice"; or Latin: glacies, "frost, ice"; and Greek: λόγος, logos, "speech" lit. "study of ice") is the study of glaciers, or more generally ice and natural phenomena that involve ice. Overview Areas of study within glaciology include glacial history and the reconstruction of past glaciation.
Types There are two general categories of glaciation which glaciologists distinguish: alpine glaciation, accumulations or "rivers of ice" confined to valleys; and continental glaciation, unrestricted accumulations which once covered much of the northern continents. Geodesy. Definition Geodesy — from the Greek word γεωδαισία or geodaisia (literally, "division of the Earth") — is primarily concerned with positioning within the temporally varying gravity field.
Somewhat obsolete nowadays, geodesy in the German-speaking world is divided into "Higher Geodesy" ("Erdmessung" or "höhere Geodäsie"), which is concerned with measuring the Earth on the global scale, and "Practical Geodesy" or "Engineering Geodesy" ("Ingenieurgeodäsie"), which is concerned with measuring specific parts or regions of the Earth, and which includes surveying. Structure of the Earth. Structure of the Earth Assumptions The force exerted by Earth's gravity can be used to calculate its mass, and by estimating the volume of the Earth, its average density can be calculated.
Astronomers can also calculate Earth's mass from its orbit and effects on nearby planetary bodies. Structure Earth's radial density distribution according to the preliminary reference earth model (PREM). Earth's gravity according to the preliminary reference earth model (PREM). Comparison to approximations using constant and linear density for Earth's interior. Figure of the Earth. The expression figure of the Earth has various meanings in geodesy according to the way it is used and the precision with which the Earth's size and shape is to be defined.
The actual topographic surface is most apparent with its variety of land forms and water areas. This is, in fact, the surface on which actual Earth measurements are made. It is not suitable, however, for exact mathematical computations, because the formulas which would be required to take the irregularities into account would necessitate a prohibitive amount of computations. 9 Really Unusual Deserts. Kilometers of sand, rocks, sandbanks, and sceneries evoking lunar landscapes are all about a journey in a desert and are certainly, a unique adventure.
All the deserts are not the same. Here are the most unusual deserts of the world. 1. A Desert With Lagoons - Lencois Maranhenses, BrasilAmazingly stretched in Brazil, it is almost impossible to believe that the desert where water has no word is full of lagoons. Situated in the State of Maranhao on the north shore, this desert is in the Lencois Maranhenses National Park where white dunes and blue lagoons have a contrasting match.The lagoons are formed due to rain drops that accumulate on the depression between dunes forming small ponds of clear water. 2. The Painted Desert (Arizona) is an expanse of badland hills, flat-topped mesas and buttes. Ringwoodite. Ringwoodite is notable for being able to contain water within its structure, present not as a liquid but as hydroxide ions (oxygen and hydrogen atoms bound together). Combined with evidence of its occurrence deep in the Earth's mantle, this suggests that there is an ocean's equivalent of water in the mantle transition zone from 410km to 660 km deep. This mineral was first identified in the Tenham meteorite in 1969, and it is inferred to be present in large quantity in the Earth’s mantle.
Ringwoodite was named after the Australian earth scientist Ted Ringwood (1930–1993), who studied polymorphic phase transitions in the common mantle minerals olivine and pyroxene at pressures equivalent to depths as great as about 600 km. Massive 'ocean' discovered towards Earth's core - 12 June 2014. Scientists discover massive amounts of water deep in the Earth's mantle. WASHINGTON - If you want to find Earth's vast reservoirs of water, you may have to look beyond the obvious places like the oceans and polar ice caps.
Scientists on Friday said massive amounts of water appear to exist deep beneath the planet's surface, trapped in a rocky layer of the mantle at depths between 250 miles and 410 miles (410 km to 660 km). But do not expect to quench your thirst down there. Earth's Magnetic Field. Geodynamics. Overview Experts in geodynamics commonly use data from geodetic GPS, InSAR, and seismology, along with numerical models, to study the evolution of the Earth's lithosphere, mantle and core. Work performed by geodynamicists may include: Physical concepts Elasticity Pressure is the part of stress that changes the volume of a solid; shear stress changes the shape. As long as the deformation is small, the equations of elasticity can be used to describe how a solid deforms under stress.
Notes See also Computational Infrastructure for Geodynamics. Gravitation. Gravitation, or gravity, is a natural phenomenon by which all physical bodies attract each other. It is most commonly recognized and experienced as the agent that gives weight to physical objects, and causes physical objects to fall toward the ground when dropped from a height. Earth’s Magnetic Field Fully Flips Fast? Exciting and scary news about earth’s magnetic field. The latest research shows that our north and south magnetic poles could reverse not only in the near future but in as little as one human lifetime. Imagine as a kid your compass app points to the north as it should but then for most of your life it doesn’t seem to know where to point anymore. Sometimes south, then west, then north-east. Finally at the end of your life your compass finally and permanently points to the south as it will for many hundreds of thousands of years.
Earth. Pole shift.