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Result search of : E
Title Description
 Epi   
A prefix signifying on or upon. 
 Electric Coal Drill   
An electric motor-driven drill designed for drilling holes in coal for placing blasting charges. Syn: coal drill 
 Extrusive   
Said of igneous rock that has been erupted onto the surface of the Earth. Extrusive rocks include lava flows and pyroclastic material such as volcanic ash. An extrusive rock. 
 Exploratory Drilling   
The drilling of boreholes from the surface or from underground workings, to seek and locate coal or mineral deposits and to establish geological structure. Exploratory drilling is frequently done from underground workings, the holes being drilled upward, horizontally, or downward as required. For underground drilling, roller bits, diamond crowns, or tungsten-carbide bits may be used and can be coring or noncoring. Rotary boring is the predominant method for exploratory work from the surface, particularly where cores of significant deposits are required. See also: borehole samples; drill sampling; underground exploration; diamond drilling. 
 Evaporation   
# A. The process, also called vaporization, by which a substance passes from the liquid or solid state to the vapor state. Limited by some to vaporization of a liquid, in contrast to sublimation, the direct vaporization of a solid. Also limited by some (e.g., hydrologists) to vaporization that takes place below the boiling point of the liquid. The opposite of condensation. AGI
B. The process by which a substance is converted from a liquid state into a vapor. Specif., the conversion of a liquid into vapor in order to remove it wholly or partly from a liquid of higher boiling point or from solids dissolved in or mixed with it 
 Elevation   
A general term for a topographic feature of any size that rises above the adjacent land or the surrounding ocean bottom; a place or station that is elevated. The vertical distance from a datum (usually mean sea level) to a point or object on the Earth’s surface; esp. the height of a ground point above the level of the sea. The term is used synonymously with altitude in referring to distance above sea level, but in modern surveying practice the term elevation is preferred to indicate heights on the Earth’s surface, whereas altitude is used to indicate the heights of points in space above the Earth’s surface. 
 Earthquake   
A movement within the Earth’s crust or mantle, caused by the sudden rupture or repositioning of underground rocks as they release stress.
 
 Erosion Thrust   
A thrust fault along which the hanging wall moved across an erosion surface.  
 Epithermal   
Said of a hydrothermal mineral deposit formed within about 1 km of the Earth’s surface and in the temperature range of 50 to 200 degrees C, occurring mainly as veins. Also, said of that depositional environment. CF: hypothermal deposit; mesothermal; leptothermal; telethermal; xenothermal. 
 Explosion Wave   
The wave or flame that passes through a uniform gaseous mixture with a permanent maximum velocity. The rate of the explosion wave is a definite physical constant for each mixture. The explosion wave travels with the velocity of sound in the burning gas, which itself is moving rapidly forward en masse in the same direction, so that the explosion wave is propagated far more rapidly than sound travels in the unburned gas.  
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